Release 1.5.8.fb.

Summary: Test Plan: Reviewers: CC: Task ID: # Blame Rev:
2026-11-07 03:22:34 -05:00 · 2013-03-13 15:38:02 -07:00
257 changed files with 4499 additions and 21848 deletions
@@ -1,16 +1,13 @@
 build_config.mk
 *.a
-*.arc
-*.d
-*.dylib*
-*.gcda
-*.gcno
 *.o
+*.dylib*
 *.so
 *.so.*
 *_test
+*.arc
+*.d
 db_bench
-db_repl_stress
 db_stress
 ldb
 leveldb_server
@@ -18,7 +15,4 @@ leveldb_shell
 manifest_dump
 sst_dump
 util/build_version.cc
-build_tools/VALGRIND_LOGS/
-coverage/COVERAGE_REPORT
-util/build_version.cc.tmp
-.gdbhistory
+db_repl_stress
@@ -14,13 +14,13 @@ OPT += -O2 -fno-omit-frame-pointer -momit-leaf-frame-pointer
 #-----------------------------------------------

 # detect what platform we're building on
-$(shell (export ROCKSDB_ROOT=$(CURDIR); $(CURDIR)/build_tools/build_detect_platform $(CURDIR)/build_config.mk))
+$(shell ./build_detect_platform build_config.mk)
 # this file is generated by the previous line to set build flags and sources
 include build_config.mk

-WARNING_FLAGS = -Wall -Werror
+WARNING_FLAGS = -Wall -Werror -Wno-unused-parameter -Wno-sign-compare
 CFLAGS += -g $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CCFLAGS) $(OPT)
-CXXFLAGS += -g $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CXXFLAGS) $(OPT) -std=gnu++0x -Woverloaded-virtual
+CXXFLAGS += -g $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CXXFLAGS) $(OPT) -std=gnu++0x

 LDFLAGS += $(PLATFORM_LDFLAGS)

@@ -31,55 +31,48 @@ MEMENVOBJECTS = $(MEMENV_SOURCES:.cc=.o)
 TESTUTIL = ./util/testutil.o
 TESTHARNESS = ./util/testharness.o $(TESTUTIL)
 VALGRIND_ERROR = 2
-VALGRIND_DIR = build_tools/VALGRIND_LOGS
+VALGRIND_DIR = VALGRIND_LOGS
 VALGRIND_VER := $(join $(VALGRIND_VER),valgrind)
 VALGRIND_OPTS = --error-exitcode=$(VALGRIND_ERROR) --leak-check=full

 TESTS = \
 	arena_test \
-	auto_roll_logger_test \
-	block_test \
 	bloom_test \
 	c_test \
 	cache_test \
 	coding_test \
+	histogram_test \
 	corruption_test \
 	crc32c_test \
 	db_test \
 	dbformat_test \
 	env_test \
-	filelock_test \
 	filename_test \
 	filter_block_test \
-	histogram_test \
 	log_test \
-	manual_compaction_test \
 	memenv_test \
-	merge_test \
-	redis_test \
-	reduce_levels_test \
 	skiplist_test \
-	stringappend_test \
 	table_test \
-	ttl_test \
+	block_test \
 	version_edit_test \
 	version_set_test \
-	write_batch_test\
-	deletefile_test
+	reduce_levels_test \
+	write_batch_test \
+	auto_roll_logger_test \
+	filelock_test
+

 TOOLS = \
+	manifest_dump \
        sst_dump \
        db_stress \
        ldb \
 	db_repl_stress

-PROGRAMS = db_bench signal_test $(TESTS) $(TOOLS)
+PROGRAMS = db_bench $(TESTS) $(TOOLS)
 BENCHMARKS = db_bench_sqlite3 db_bench_tree_db

-# The library name is configurable since we are maintaining libraries of both
-# debug/release mode.
-LIBNAME = librocksdb
-LIBRARY = ${LIBNAME}.a
+LIBRARY = libleveldb.a
 MEMENVLIBRARY = libmemenv.a

 default: all
@@ -88,15 +81,15 @@ default: all
 ifneq ($(PLATFORM_SHARED_EXT),)

 ifneq ($(PLATFORM_SHARED_VERSIONED),true)
-SHARED1 = ${LIBNAME}.$(PLATFORM_SHARED_EXT)
+SHARED1 = libleveldb.$(PLATFORM_SHARED_EXT)
 SHARED2 = $(SHARED1)
 SHARED3 = $(SHARED1)
 SHARED = $(SHARED1)
 else
 # Update db.h if you change these.
-SHARED_MAJOR = 2
-SHARED_MINOR = 0
-SHARED1 = ${LIBNAME}.$(PLATFORM_SHARED_EXT)
+SHARED_MAJOR = 1
+SHARED_MINOR = 5
+SHARED1 = libleveldb.$(PLATFORM_SHARED_EXT)
 SHARED2 = $(SHARED1).$(SHARED_MAJOR)
 SHARED3 = $(SHARED1).$(SHARED_MAJOR).$(SHARED_MINOR)
 SHARED = $(SHARED1) $(SHARED2) $(SHARED3)
@@ -107,25 +100,15 @@ $(SHARED2): $(SHARED3)
 endif

 $(SHARED3):
-	$(CXX) $(LDFLAGS) $(PLATFORM_SHARED_LDFLAGS)$(SHARED2) $(CXXFLAGS) $(COVERAGEFLAGS) $(PLATFORM_SHARED_CFLAGS) $(SOURCES) -o $(SHARED3)
+	$(CXX) $(LDFLAGS) $(PLATFORM_SHARED_LDFLAGS)$(SHARED2) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) $(SOURCES) -o $(SHARED3)

 endif  # PLATFORM_SHARED_EXT

 all: $(SHARED) $(LIBRARY) $(PROGRAMS)

-.PHONY: blackbox_crash_test check clean coverage crash_test ldb_tests \
-	release tags valgrind_check whitebox_crash_test
-
 release:
-	$(MAKE) clean
-	OPT=-DNDEBUG $(MAKE) -j32
-
-coverage:
-	$(MAKE) clean
-	COVERAGEFLAGS="-fprofile-arcs -ftest-coverage" LDFLAGS+="-lgcov" $(MAKE) all check
-	(cd coverage; ./coverage_test.sh)
-	# Delete intermediate files
-	find . -type f -regex ".*\.\(\(gcda\)\|\(gcno\)\)" | xargs --no-run-if-empty rm
+	make clean
+	OPT=-DNDEBUG make -j32

 check: all $(PROGRAMS) $(TESTS) $(TOOLS) ldb_tests
 	for t in $(TESTS); do echo "***** Running $$t"; ./$$t || exit 1; done
@@ -133,16 +116,7 @@ check: all $(PROGRAMS) $(TESTS) $(TOOLS) ldb_tests
 ldb_tests: all $(PROGRAMS) $(TOOLS)
 	python tools/ldb_test.py

-crash_test: blackbox_crash_test whitebox_crash_test
-
-blackbox_crash_test: db_stress
-	python -u tools/db_crashtest.py
-
-whitebox_crash_test: db_stress
-	python -u tools/db_crashtest2.py
-
 valgrind_check: all $(PROGRAMS) $(TESTS)
-	mkdir -p $(VALGRIND_DIR)
 	echo TESTS THAT HAVE VALGRIND ERRORS > $(VALGRIND_DIR)/valgrind_failed_tests; \
 	echo TIMES in seconds TAKEN BY TESTS ON VALGRIND > $(VALGRIND_DIR)/valgrind_tests_times; \
 	for t in $(filter-out skiplist_test,$(TESTS)); do \
@@ -156,151 +130,119 @@ valgrind_check: all $(PROGRAMS) $(TESTS)
 	done

 clean:
-	-rm -f $(PROGRAMS) $(BENCHMARKS) $(LIBRARY) $(SHARED) $(MEMENVLIBRARY) $(THRIFTSERVER) build_config.mk
+	-rm -f $(PROGRAMS) $(BENCHMARKS) $(LIBRARY) $(SHARED) $(MEMENVLIBRARY) $(THRIFTSERVER) */*.o */*/*.o ios-x86/*/*.o ios-arm/*/*.o build_config.mk
 	-rm -rf ios-x86/* ios-arm/*
-	-find . -name "*.[od]" | xargs --no-run-if-empty rm
-	-find . -type f -regex ".*\.\(\(gcda\)\|\(gcno\)\)" | xargs --no-run-if-empty rm
-tags:
-	ctags * -R
-	cscope -b `find . -name '*.cc'` `find . -name '*.h'`

-# ---------------------------------------------------------------------------
-# 	Unit tests and tools
-# ---------------------------------------------------------------------------
 $(LIBRARY): $(LIBOBJECTS)
 	rm -f $@
 	$(AR) -rs $@ $(LIBOBJECTS)

+
 db_bench: db/db_bench.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) db/db_bench.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) db/db_bench.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS)

 db_stress: tools/db_stress.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) tools/db_stress.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) tools/db_stress.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS)

 db_repl_stress: tools/db_repl_stress.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) tools/db_repl_stress.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) tools/db_repl_stress.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS)

 db_bench_sqlite3: doc/bench/db_bench_sqlite3.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) doc/bench/db_bench_sqlite3.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) -lsqlite3 $(COVERAGEFLAGS)
+	$(CXX) doc/bench/db_bench_sqlite3.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) -lsqlite3

 db_bench_tree_db: doc/bench/db_bench_tree_db.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) doc/bench/db_bench_tree_db.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) -lkyotocabinet $(COVERAGEFLAGS)
-
-signal_test: util/signal_test.o $(LIBOBJECTS)
-	$(CXX) util/signal_test.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) doc/bench/db_bench_tree_db.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) -lkyotocabinet

 arena_test: util/arena_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/arena_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) util/arena_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 bloom_test: util/bloom_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/bloom_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) util/bloom_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 c_test: db/c_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/c_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) db/c_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 cache_test: util/cache_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/cache_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) util/cache_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 coding_test: util/coding_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/coding_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
-
-stringappend_test: utilities/merge_operators/string_append/stringappend_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) utilities/merge_operators/string_append/stringappend_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
-
-redis_test: utilities/redis/redis_lists_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) utilities/redis/redis_lists_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) util/coding_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 histogram_test: util/histogram_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/histogram_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o$@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) util/histogram_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o$@ $(LDFLAGS)

 corruption_test: db/corruption_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/corruption_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) db/corruption_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 crc32c_test: util/crc32c_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/crc32c_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) util/crc32c_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 db_test: db/db_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
-
-perf_context_test: db/perf_context_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/perf_context_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
-
-ttl_test: utilities/ttl/ttl_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) utilities/ttl/ttl_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) db/db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 dbformat_test: db/dbformat_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/dbformat_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) db/dbformat_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 env_test: util/env_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/env_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) util/env_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 filename_test: db/filename_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/filename_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) db/filename_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 filter_block_test: table/filter_block_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) table/filter_block_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) table/filter_block_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 log_test: db/log_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/log_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) db/log_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 table_test: table/table_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) table/table_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) table/table_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 block_test: table/block_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) table/block_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) table/block_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 skiplist_test: db/skiplist_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/skiplist_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) db/skiplist_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 version_edit_test: db/version_edit_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/version_edit_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) db/version_edit_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 version_set_test: db/version_set_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/version_set_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) db/version_set_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 reduce_levels_test: tools/reduce_levels_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) tools/reduce_levels_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) tools/reduce_levels_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 write_batch_test: db/write_batch_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/write_batch_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
-
-merge_test: db/merge_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/merge_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
-
-deletefile_test: db/deletefile_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/deletefile_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/write_batch_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 $(MEMENVLIBRARY) : $(MEMENVOBJECTS)
 	rm -f $@
 	$(AR) -rs $@ $(MEMENVOBJECTS)

 memenv_test : helpers/memenv/memenv_test.o $(MEMENVLIBRARY) $(LIBRARY) $(TESTHARNESS)
-	$(CXX) helpers/memenv/memenv_test.o $(MEMENVLIBRARY) $(LIBRARY) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) helpers/memenv/memenv_test.o $(MEMENVLIBRARY) $(LIBRARY) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

-manual_compaction_test: util/manual_compaction_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/manual_compaction_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+leveldb_shell: tools/shell/ShellContext.o tools/shell/ShellState.o tools/shell/LeveldbShell.o tools/shell/DBClientProxy.o tools/shell/ShellContext.h tools/shell/ShellState.h tools/shell/DBClientProxy.h $(LIBOBJECTS)
+	$(CXX) tools/shell/ShellContext.o tools/shell/ShellState.o tools/shell/LeveldbShell.o tools/shell/DBClientProxy.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

-rocksdb_shell: tools/shell/ShellContext.o tools/shell/ShellState.o tools/shell/LeveldbShell.o tools/shell/DBClientProxy.o tools/shell/ShellContext.h tools/shell/ShellState.h tools/shell/DBClientProxy.h $(LIBOBJECTS)
-	$(CXX) tools/shell/ShellContext.o tools/shell/ShellState.o tools/shell/LeveldbShell.o tools/shell/DBClientProxy.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+DBClientProxy_test: tools/shell/test/DBClientProxyTest.o tools/shell/DBClientProxy.o $(LIBRARY) 
+	$(CXX) tools/shell/test/DBClientProxyTest.o tools/shell/DBClientProxy.o $(LIBRARY) $(EXEC_LDFLAGS) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS)

-DBClientProxy_test: tools/shell/test/DBClientProxyTest.o tools/shell/DBClientProxy.o $(LIBRARY)
-	$(CXX) tools/shell/test/DBClientProxyTest.o tools/shell/DBClientProxy.o $(LIBRARY) $(EXEC_LDFLAGS) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
+manifest_dump: tools/manifest_dump.o $(LIBOBJECTS)
+	$(CXX) tools/manifest_dump.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 filelock_test: util/filelock_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/filelock_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) util/filelock_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 auto_roll_logger_test: util/auto_roll_logger_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/auto_roll_logger_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) util/auto_roll_logger_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 sst_dump: tools/sst_dump.o $(LIBOBJECTS)
-	$(CXX) tools/sst_dump.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+	$(CXX) tools/sst_dump.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 ldb: tools/ldb.o $(LIBOBJECTS)
-	$(CXX) tools/ldb.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
-
-# ---------------------------------------------------------------------------
-#  	Platform-specific compilation
-# ---------------------------------------------------------------------------
+	$(CXX) tools/ldb.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 ifeq ($(PLATFORM), IOS)
 # For iOS, create universal object files to be used on both the simulator and
@@ -312,9 +254,9 @@ IOSVERSION=$(shell defaults read $(PLATFORMSROOT)/iPhoneOS.platform/versionCFBun

 .cc.o:
 	mkdir -p ios-x86/$(dir $@)
-	$(SIMULATORROOT)/usr/bin/$(CXX) $(CXXFLAGS) -isysroot $(SIMULATORROOT)/SDKs/iPhoneSimulator$(IOSVERSION).sdk -arch i686 -c $< -o ios-x86/$@ $(COVERAGEFLAGS)
+	$(SIMULATORROOT)/usr/bin/$(CXX) $(CXXFLAGS) -isysroot $(SIMULATORROOT)/SDKs/iPhoneSimulator$(IOSVERSION).sdk -arch i686 -c $< -o ios-x86/$@
 	mkdir -p ios-arm/$(dir $@)
-	$(DEVICEROOT)/usr/bin/$(CXX) $(CXXFLAGS) -isysroot $(DEVICEROOT)/SDKs/iPhoneOS$(IOSVERSION).sdk -arch armv6 -arch armv7 -c $< -o ios-arm/$@ $(COVERAGEFLAGS)
+	$(DEVICEROOT)/usr/bin/$(CXX) $(CXXFLAGS) -isysroot $(DEVICEROOT)/SDKs/iPhoneOS$(IOSVERSION).sdk -arch armv6 -arch armv7 -c $< -o ios-arm/$@
 	lipo ios-x86/$@ ios-arm/$@ -create -output $@

 .c.o:
@@ -326,26 +268,17 @@ IOSVERSION=$(shell defaults read $(PLATFORMSROOT)/iPhoneOS.platform/versionCFBun

 else
 .cc.o:
-	$(CXX) $(CXXFLAGS) -c $< -o $@ $(COVERAGEFLAGS)
+	$(CXX) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) -c $< -o $@

 .c.o:
-	$(CC) $(CFLAGS) -c $< -o $@
+	$(CC) $(CFLAGS) $(PLATFORM_SHARED_CFLAGS) -c $< -o $@
 endif

-# ---------------------------------------------------------------------------
-#  	Source files dependencies detection
-# ---------------------------------------------------------------------------
-
-# Add proper dependency support so changing a .h file forces a .cc file to
-# rebuild.
-
-# The .d file indicates .cc file's dependencies on .h files. We generate such
-# dependency by g++'s -MM option, whose output is a make dependency rule.
-# The sed command makes sure the "target" file in the generated .d file has
-# the correct path prefix.
 %.d: %.cc
-	$(CXX) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) -MM $< -o $@
-	@sed -i -e 's|.*:|$*.o:|' $@
+	$(CXX) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) -MM $< -o $*.d
+	@cp -f $*.d $*.d.tmp
+	@sed -e 's|.*:|$*.o:|' < $*.d.tmp > $*.d
+	@rm -f $*.d.tmp

 DEPFILES = $(filter-out util/build_version.d,$(SOURCES:.cc=.d))

@@ -354,3 +287,4 @@ depend: $(DEPFILES)
 ifneq ($(MAKECMDGOALS),clean)
 -include $(DEPFILES)
 endif
+
@@ -1,7 +1,5 @@
 rocksdb: A persistent key-value store for flash storage
-Authors: * The Facebook Database Engineering Team
-         * Build on earlier work on leveldb by Sanjay Ghemawat
-           (sanjay@google.com) and Jeff Dean (jeff@google.com)
+Authors: The Facebook Database Engineering Team

 This code is a library that forms the core building block for a fast
 key value server, especially suited for storing data on flash drives.
@@ -19,64 +17,45 @@ persistent key/value store.
 See doc/index.html for more explanation.
 See doc/impl.html for a brief overview of the implementation.

-The public interface is in include/*.  Callers should not include or
+The public interface is in include/*.h.  Callers should not include or
 rely on the details of any other header files in this package.  Those
 internal APIs may be changed without warning.

 Guide to header files:

-include/rocksdb/db.h
+include/db.h
    Main interface to the DB: Start here

-include/rocksdb/options.h
+include/options.h
    Control over the behavior of an entire database, and also
    control over the behavior of individual reads and writes.

-include/rocksdb/comparator.h
+include/comparator.h
    Abstraction for user-specified comparison function.  If you want
    just bytewise comparison of keys, you can use the default comparator,
    but clients can write their own comparator implementations if they
    want custom ordering (e.g. to handle different character
    encodings, etc.)

-include/rocksdb/iterator.h
+include/iterator.h
    Interface for iterating over data. You can get an iterator
    from a DB object.

-include/rocksdb/write_batch.h
+include/write_batch.h
    Interface for atomically applying multiple updates to a database.

-include/rocksdb/slice.h
+include/slice.h
    A simple module for maintaining a pointer and a length into some
    other byte array.

-include/rocksdb/status.h
+include/status.h
    Status is returned from many of the public interfaces and is used
    to report success and various kinds of errors.

-include/rocksdb/env.h
+include/env.h
    Abstraction of the OS environment.  A posix implementation of
    this interface is in util/env_posix.cc

-include/rocksdb/table_builder.h
+include/table.h
+include/table_builder.h
    Lower-level modules that most clients probably won't use directly
-
-include/rocksdb/cache.h
-    An API for the block cache.
-
-include/rocksdb/compaction_filter.h
-    An API for a application filter invoked on every compaction.
-
-include/rocksdb/filter_policy.h
-    An API for configuring a bloom filter.
-
-include/rocksdb/memtablerep.h
-    An API for implementing a memtable.
-
-include/rocksdb/statistics.h
-    An API to retrieve various database statistics.
-
-include/rocksdb/transaction_log.h
-    An API to retrieve transaction logs from a database.
-
-
@@ -1,3 +1,3 @@
 * Detailed instructions on how to compile using fbcode and jemalloc

-* Latest release is 2.4.fb
+* Latest release is 1.5.8.fb
@@ -0,0 +1,4 @@
+This directory stores the tests that failed valgrind and the times associated
+with the failed runs.
+"make valgrind_check" can be invoked to call valgrind on the rocksdb tests and
+generate files in this directory
@@ -31,9 +31,9 @@ fi
 # Default to fbcode gcc on internal fb machines
 if [ -d /mnt/gvfs/third-party -a -z "$CXX" ]; then
    if [ -z "$USE_CLANG" ]; then
-        source $PWD/build_tools/fbcode.gcc471.sh
+        source fbcode.gcc471.sh
    else
-        source $PWD/build_tools/fbcode.clang31.sh
+        source fbcode.clang31.sh
    fi
 fi

@@ -64,9 +64,6 @@ PLATFORM_SHARED_LDFLAGS="${EXEC_LDFLAGS_SHARED} -shared -Wl,-soname -Wl,"
 PLATFORM_SHARED_CFLAGS="-fPIC"
 PLATFORM_SHARED_VERSIONED=true

-# generic port files (working on all platform by #ifdef) go directly in /port
-GENERIC_PORT_FILES=`find $ROCKSDB_ROOT/port -name '*.cc' | tr "\n" " "`
-
 # On GCC, we pick libc's memcmp over GCC's memcmp via -fno-builtin-memcmp
 case "$TARGET_OS" in
    Darwin)
@@ -74,52 +71,52 @@ case "$TARGET_OS" in
        COMMON_FLAGS="$COMMON_FLAGS -fno-builtin-memcmp -DOS_MACOSX"
        PLATFORM_SHARED_EXT=dylib
        PLATFORM_SHARED_LDFLAGS="-dynamiclib -install_name "
-        # PORT_FILES=port/darwin/darwin_specific.cc
+        PORT_FILE=port/port_posix.cc
        ;;
    Linux)
        PLATFORM=OS_LINUX
-        COMMON_FLAGS="$COMMON_FLAGS -DOS_LINUX"
+        COMMON_FLAGS="$COMMON_FLAGS -DOS_LINUX -fPIC"
        if [ -z "$USE_CLANG" ]; then
            COMMON_FLAGS="$COMMON_FLAGS -fno-builtin-memcmp"
        fi
-        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lpthread -lrt"
-        # PORT_FILES=port/linux/linux_specific.cc
+        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lpthread"
+        PORT_FILE=port/port_posix.cc
        ;;
    SunOS)
        PLATFORM=OS_SOLARIS
        COMMON_FLAGS="$COMMON_FLAGS -fno-builtin-memcmp -D_REENTRANT -DOS_SOLARIS"
        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lpthread -lrt"
-        # PORT_FILES=port/sunos/sunos_specific.cc
+        PORT_FILE=port/port_posix.cc
        ;;
    FreeBSD)
        PLATFORM=OS_FREEBSD
        COMMON_FLAGS="$COMMON_FLAGS -fno-builtin-memcmp -D_REENTRANT -DOS_FREEBSD"
        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lpthread"
-        # PORT_FILES=port/freebsd/freebsd_specific.cc
+        PORT_FILE=port/port_posix.cc
        ;;
    NetBSD)
        PLATFORM=OS_NETBSD
        COMMON_FLAGS="$COMMON_FLAGS -fno-builtin-memcmp -D_REENTRANT -DOS_NETBSD"
        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lpthread -lgcc_s"
-        # PORT_FILES=port/netbsd/netbsd_specific.cc
+        PORT_FILE=port/port_posix.cc
        ;;
    OpenBSD)
        PLATFORM=OS_OPENBSD
        COMMON_FLAGS="$COMMON_FLAGS -fno-builtin-memcmp -D_REENTRANT -DOS_OPENBSD"
        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -pthread"
-        # PORT_FILES=port/openbsd/openbsd_specific.cc
+        PORT_FILE=port/port_posix.cc
        ;;
    DragonFly)
        PLATFORM=OS_DRAGONFLYBSD
        COMMON_FLAGS="$COMMON_FLAGS -fno-builtin-memcmp -D_REENTRANT -DOS_DRAGONFLYBSD"
        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lpthread"
-        # PORT_FILES=port/dragonfly/dragonfly_specific.cc
+        PORT_FILE=port/port_posix.cc
        ;;
    OS_ANDROID_CROSSCOMPILE)
        PLATFORM=OS_ANDROID
 	COMMON_FLAGS="$COMMON_FLAGS -fno-builtin-memcmp -D_REENTRANT -DOS_ANDROID -DLEVELDB_PLATFORM_POSIX"
 	PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS "  # All pthread features are in the Android C library
-        # PORT_FILES=port/android/android.cc
+        PORT_FILE=port/port_posix.cc
        CROSS_COMPILE=true
        ;;
    *)
@@ -127,13 +124,13 @@ case "$TARGET_OS" in
        exit 1
 esac

-$PWD/build_tools/build_detect_version
+./build_detect_version

 # We want to make a list of all cc files within util, db, table, and helpers
 # except for the test and benchmark files. By default, find will output a list
 # of all files matching either rule, so we need to append -print to make the
 # prune take effect.
-DIRS="util db table utilities"
+DIRS="util db table"
 if test "$USE_THRIFT"; then
  DIRS="$DIRS thrift/server_utils.cpp thrift/gen-cpp "
  THRIFTSERVER=leveldb_server
@@ -146,13 +143,13 @@ fi
 set -f # temporarily disable globbing so that our patterns arent expanded
 PRUNE_TEST="-name *test*.cc -prune"
 PRUNE_BENCH="-name *_bench.cc -prune"
-PORTABLE_FILES=`cd $ROCKSDB_ROOT; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cc' -print | sort | tr "\n" " "`
-PORTABLE_CPP=`cd $ROCKSDB_ROOT; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cpp' -print | sort | tr "\n" " "`
+PORTABLE_FILES=`find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cc' -print | sort | tr "\n" " "`
+PORTABLE_CPP=`find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cpp' -print | sort | tr "\n" " "`
 set +f # re-enable globbing

 # The sources consist of the portable files, plus the platform-specific port
 # file.
-echo "SOURCES=$PORTABLE_FILES $GENERIC_PORT_FILES $PORT_FILES" >> $OUTPUT
+echo "SOURCES=$PORTABLE_FILES $PORT_FILE" >> $OUTPUT
 echo "SOURCESCPP=$PORTABLE_CPP" >> $OUTPUT
 echo "MEMENV_SOURCES=helpers/memenv/memenv.cc" >> $OUTPUT

@@ -0,0 +1,30 @@
+#!/bin/sh
+#
+# Record the version of the source that we are compiling.
+# We keep a record of the git revision in util/version.cc. This source file
+# is then built as a regular source file as part of the compilation process.
+# One can run "strings executable_filename | grep _build_" to find the version of
+# the source that we used to build the executable file.
+#
+
+# create git version file
+VFILE=$(mktemp)
+trap "rm $VFILE" EXIT
+
+# check to see if git is in the path
+which git > /dev/null
+
+if [ "$?" = 0 ]; then
+  env -i git rev-parse HEAD | awk ' BEGIN {print "#include \"build_version.h\""} {print "const char * leveldb_build_git_sha = \"leveldb_build_git_sha:" $0"\";"} END {}' >  ${VFILE}
+else
+  echo "git not found"| awk ' BEGIN {print "#include \"build_version.h\""} {print "const char * leveldb_build_git_sha = \"leveldb_build_git_sha:git not found\";"} END {}' > ${VFILE}
+fi
+
+date | awk 'BEGIN {} {print "const char * leveldb_build_git_datetime = \"leveldb_build_git_datetime:"$0"\";"} END {} ' >> ${VFILE}
+echo "const char * leveldb_build_compile_date = __DATE__;" >> ${VFILE}
+echo "const char * leveldb_build_compile_time = __TIME__;" >> ${VFILE}
+
+OUTFILE=util/build_version.cc
+if [ ! -e $OUTFILE ] || ! cmp -s $VFILE $OUTFILE; then
+    cp $VFILE $OUTFILE
+fi
@@ -1,42 +0,0 @@
-#!/bin/sh
-#
-# Record the version of the source that we are compiling.
-# We keep a record of the git revision in util/version.cc. This source file
-# is then built as a regular source file as part of the compilation process.
-# One can run "strings executable_filename | grep _build_" to find the version of
-# the source that we used to build the executable file.
-#
-
-# create git version file
-VFILE=$ROCKSDB_ROOT/util/build_version.cc.tmp
-trap "rm $VFILE" EXIT
-
-# check to see if git is in the path
-which git > /dev/null
-
-if [ "$?" = 0 ]; then
-  env -i git rev-parse HEAD |
-  awk '
-  BEGIN {
-    print "#include \"build_version.h\"\n"
-  }
-  { print "const char* leveldb_build_git_sha = \"leveldb_build_git_sha:" $0"\";" }
-  ' >  ${VFILE}
-else
-  echo "git not found" |
-  awk '
-    BEGIN {
-      print "#include \"build_version.h\""
-    }
-    { print "const char* leveldb_build_git_sha = \"leveldb_build_git_sha:git not found\";" }
-    ' > ${VFILE}
-fi
-
-echo "const char* leveldb_build_git_datetime = \"leveldb_build_git_datetime:$(date)\";" >> ${VFILE}
-echo "const char* leveldb_build_compile_date = __DATE__;" >> ${VFILE}
-echo "const char* leveldb_build_compile_time = __TIME__;" >> ${VFILE}
-
-OUTFILE=$ROCKSDB_ROOT/util/build_version.cc
-if [ ! -e $OUTFILE ] || ! cmp -s $VFILE $OUTFILE; then
-    cp $VFILE $OUTFILE
-fi
@@ -1,73 +0,0 @@
-#!/bin/bash
-
-# Exit on error.
-set -e
-
-if [ -n "$USE_CLANG" ]; then
-  echo "Error: Coverage test is supported only for gcc."
-  exit 1
-fi
-
-ROOT=".."
-# Fetch right version of gcov
-if [ -d /mnt/gvfs/third-party -a -z "$CXX" ]; then
-  source $ROOT/build_tools/fbcode.gcc471.sh
-  GCOV=$TOOLCHAIN_EXECUTABLES/gcc/gcc-4.7.1/cc6c9dc/bin/gcov
-else
-  GCOV=$(which gcov)
-fi
-
-COVERAGE_DIR="$PWD/COVERAGE_REPORT"
-mkdir -p $COVERAGE_DIR
-
-# Find all gcno files to generate the coverage report
-
-GCNO_FILES=`find $ROOT -name "*.gcno"`
-$GCOV --preserve-paths --relative-only --no-output $GCNO_FILES 2>/dev/null |
-  # Parse the raw gcov report to more human readable form.
-  python $ROOT/coverage/parse_gcov_output.py |
-  # Write the output to both stdout and report file.
-  tee $COVERAGE_DIR/coverage_report_all.txt &&
-echo -e "Generated coverage report for all files: $COVERAGE_DIR/coverage_report_all.txt\n"
-
-# TODO: we also need to get the files of the latest commits.
-# Get the most recently committed files.
-LATEST_FILES=`
-  git show --pretty="format:" --name-only HEAD |
-  grep -v "^$" |
-  paste -s -d,`
-RECENT_REPORT=$COVERAGE_DIR/coverage_report_recent.txt
-
-echo -e "Recently updated files: $LATEST_FILES\n" > $RECENT_REPORT
-$GCOV --preserve-paths --relative-only --no-output $GCNO_FILES 2>/dev/null |
-  python $ROOT/coverage/parse_gcov_output.py -interested-files $LATEST_FILES |
-  tee -a $RECENT_REPORT &&
-echo -e "Generated coverage report for recently updated files: $RECENT_REPORT\n"
-
-# Generate the html report. If we cannot find lcov in this machine, we'll simply
-# skip this step.
-echo "Generating the html coverage report..."
-
-LCOV=$(which lcov || true 2>/dev/null)
-if [ -z $LCOV ]
-then
-  echo "Skip: Cannot find lcov to generate the html report."
-  exit 0
-fi
-
-LCOV_VERSION=$(lcov -v | grep 1.1 || true)
-if [ $LCOV_VERSION ]
-then
-  echo "Not supported lcov version. Expect lcov 1.1."
-  exit 0
-fi
-
-(cd $ROOT; lcov --no-external \
-     --capture  \
-     --directory $PWD \
-     --gcov-tool $GCOV \
-     --output-file $COVERAGE_DIR/coverage.info)
-
-genhtml $COVERAGE_DIR/coverage.info -o $COVERAGE_DIR
-
-echo "HTML Coverage report is generated in $COVERAGE_DIR"
@@ -1,118 +0,0 @@
-import optparse
-import re
-import sys
-
-from optparse import OptionParser
-
-# the gcov report follows certain pattern. Each file will have two lines
-# of report, from which we can extract the file name, total lines and coverage
-# percentage.
-def parse_gcov_report(gcov_input):
-    per_file_coverage = {}
-    total_coverage = None
-
-    for line in sys.stdin:
-        line = line.strip()
-
-        # --First line of the coverage report (with file name in it)?
-        match_obj = re.match("^File '(.*)'$", line)
-        if match_obj:
-            # fetch the file name from the first line of the report.
-            current_file = match_obj.group(1)
-            continue
-
-        # -- Second line of the file report (with coverage percentage)
-        match_obj = re.match("^Lines executed:(.*)% of (.*)", line)
-
-        if match_obj:
-            coverage = float(match_obj.group(1))
-            lines = int(match_obj.group(2))
-
-            if current_file is not None:
-                per_file_coverage[current_file] = (coverage, lines)
-                current_file = None
-            else:
-                # If current_file is not set, we reach the last line of report,
-                # which contains the summarized coverage percentage.
-                total_coverage = (coverage, lines)
-            continue
-
-        # If the line's pattern doesn't fall into the above categories. We
-        # can simply ignore them since they're either empty line or doesn't
-        # find executable lines of the given file.
-        current_file = None
-
-    return per_file_coverage, total_coverage
-
-def get_option_parser():
-    usage = "Parse the gcov output and generate more human-readable code " +\
-            "coverage report."
-    parser = OptionParser(usage)
-
-    parser.add_option(
-        "--interested-files", "-i",
-        dest="filenames",
-        help="Comma separated files names. if specified, we will display " +
-             "the coverage report only for interested source files. " +
-             "Otherwise we will display the coverage report for all " +
-             "source files."
-    )
-    return parser
-
-def display_file_coverage(per_file_coverage, total_coverage):
-    # To print out auto-adjustable column, we need to know the longest
-    # length of file names.
-    max_file_name_length = max(
-        len(fname) for fname in per_file_coverage.keys()
-    )
-
-    # -- Print header
-    # size of separator is determined by 3 column sizes:
-    # file name, coverage percentage and lines.
-    header_template = \
-        "%" + str(max_file_name_length) + "s\t%s\t%s"
-    separator = "-" * (max_file_name_length + 10 + 20)
-    print header_template % ("Filename", "Coverage", "Lines")
-    print separator
-
-    # -- Print body
-    # template for printing coverage report for each file.
-    record_template = "%" + str(max_file_name_length) + "s\t%5.2f%%\t%10d"
-
-    for fname, coverage_info in per_file_coverage.items():
-        coverage, lines = coverage_info
-        print record_template % (fname, coverage, lines)
-
-    # -- Print footer
-    if total_coverage:
-        print separator
-        print record_template % ("Total", total_coverage[0], total_coverage[1])
-
-def report_coverage():
-    parser = get_option_parser()
-    (options, args) = parser.parse_args()
-
-    interested_files = set()
-    if options.filenames is not None:
-        interested_files = set(f.strip() for f in options.filenames.split(','))
-
-    # To make things simple, right now we only read gcov report from the input
-    per_file_coverage, total_coverage = parse_gcov_report(sys.stdin)
-
-    # Check if we need to display coverage info for interested files.
-    if len(interested_files):
-        per_file_coverage = dict(
-            (fname, per_file_coverage[fname]) for fname in interested_files
-            if fname in per_file_coverage
-        )
-        # If we only interested in several files, it makes no sense to report
-        # the total_coverage
-        total_coverage = None
-
-    if not len(per_file_coverage):
-        print >> sys.stderr, "Cannot find coverage info for the given files."
-        return
-    display_file_coverage(per_file_coverage, total_coverage)
-
-if __name__ == "__main__":
-    report_coverage()
@@ -6,20 +6,17 @@

 #include "db/filename.h"
 #include "db/dbformat.h"
-#include "db/merge_helper.h"
 #include "db/table_cache.h"
 #include "db/version_edit.h"
-#include "rocksdb/db.h"
-#include "rocksdb/env.h"
-#include "rocksdb/iterator.h"
-#include "util/stop_watch.h"
+#include "leveldb/db.h"
+#include "leveldb/env.h"
+#include "leveldb/iterator.h"

-namespace rocksdb {
+namespace leveldb {

 Status BuildTable(const std::string& dbname,
                  Env* env,
                  const Options& options,
-                  const EnvOptions& soptions,
                  TableCache* table_cache,
                  Iterator* iter,
                  FileMetaData* meta,
@@ -28,7 +25,6 @@ Status BuildTable(const std::string& dbname,
                  const SequenceNumber earliest_seqno_in_memtable) {
  Status s;
  meta->file_size = 0;
-  meta->smallest_seqno = meta->largest_seqno = 0;
  iter->SeekToFirst();

  // If the sequence number of the smallest entry in the memtable is
@@ -42,7 +38,7 @@ Status BuildTable(const std::string& dbname,
  std::string fname = TableFileName(dbname, meta->number);
  if (iter->Valid()) {
    unique_ptr<WritableFile> file;
-    s = env->NewWritableFile(fname, &file, soptions);
+    s = env->NewWritableFile(fname, &file);
    if (!s.ok()) {
      return s;
    }
@@ -51,106 +47,47 @@ Status BuildTable(const std::string& dbname,
    // the first key is the smallest key
    Slice key = iter->key();
    meta->smallest.DecodeFrom(key);
-    meta->smallest_seqno = GetInternalKeySeqno(key);
-    meta->largest_seqno = meta->smallest_seqno;
-
-    MergeHelper merge(user_comparator, options.merge_operator.get(),
-                      options.info_log.get(),
-                      true /* internal key corruption is not ok */);

    if (purge) {
-      // Ugly walkaround to avoid compiler error for release build
-      bool ok __attribute__((unused)) = true;
-
-      // Will write to builder if current key != prev key
      ParsedInternalKey prev_ikey;
+      std::string prev_value;
      std::string prev_key;
-      bool is_first_key = true;    // Also write if this is the very first key

-      while (iter->Valid()) {
-        bool iterator_at_next = false;
+      // store first key-value
+      prev_key.assign(key.data(), key.size());
+      prev_value.assign(iter->value().data(), iter->value().size());
+      ParseInternalKey(Slice(prev_key), &prev_ikey);
+      assert(prev_ikey.sequence >= earliest_seqno_in_memtable);

-        // Get current key
+      for (iter->Next(); iter->Valid(); iter->Next()) {
        ParsedInternalKey this_ikey;
        Slice key = iter->key();
-        Slice value = iter->value();
-
-        // In-memory key corruption is not ok;
-        // TODO: find a clean way to treat in memory key corruption
-        ok = ParseInternalKey(key, &this_ikey);
-        assert(ok);
+        ParseInternalKey(key, &this_ikey);
        assert(this_ikey.sequence >= earliest_seqno_in_memtable);

-        // If the key is the same as the previous key (and it is not the
-        // first key), then we skip it, since it is an older version.
-        // Otherwise we output the key and mark it as the "new" previous key.
-        if (!is_first_key && !user_comparator->Compare(prev_ikey.user_key,
-                                                       this_ikey.user_key)) {
+        if (user_comparator->Compare(prev_ikey.user_key, this_ikey.user_key)) {
+          // This key is different from previous key.
+          // Output prev key and remember current key
+          builder->Add(Slice(prev_key), Slice(prev_value));
+          prev_key.assign(key.data(), key.size());
+          prev_value.assign(iter->value().data(), iter->value().size());
+          ParseInternalKey(Slice(prev_key), &prev_ikey);
+        } else {
          // seqno within the same key are in decreasing order
          assert(this_ikey.sequence < prev_ikey.sequence);
-        } else {
-          is_first_key = false;
-
-          if (this_ikey.type == kTypeMerge) {
-            // Handle merge-type keys using the MergeHelper
-            merge.MergeUntil(iter, 0 /* don't worry about snapshot */);
-            iterator_at_next = true;
-            if (merge.IsSuccess()) {
-              // Merge completed correctly.
-              // Add the resulting merge key/value and continue to next
-              builder->Add(merge.key(), merge.value());
-              prev_key.assign(merge.key().data(), merge.key().size());
-              ok = ParseInternalKey(Slice(prev_key), &prev_ikey);
-              assert(ok);
-            } else {
-              // Merge did not find a Put/Delete.
-              // Can not compact these merges into a kValueType.
-              // Write them out one-by-one. (Proceed back() to front())
-              const std::deque<std::string>& keys = merge.keys();
-              const std::deque<std::string>& values = merge.values();
-              assert(keys.size() == values.size() && keys.size() >= 1);
-              std::deque<std::string>::const_reverse_iterator key_iter;
-              std::deque<std::string>::const_reverse_iterator value_iter;
-              for (key_iter=keys.rbegin(), value_iter = values.rbegin();
-                   key_iter != keys.rend() && value_iter != values.rend();
-                   ++key_iter, ++value_iter) {
-
-                builder->Add(Slice(*key_iter), Slice(*value_iter));
-              }
-
-              // Sanity check. Both iterators should end at the same time
-              assert(key_iter == keys.rend() && value_iter == values.rend());
-
-              prev_key.assign(keys.front());
-              ok = ParseInternalKey(Slice(prev_key), &prev_ikey);
-              assert(ok);
-            }
-          } else {
-            // Handle Put/Delete-type keys by simply writing them
-            builder->Add(key, value);
-            prev_key.assign(key.data(), key.size());
-            ok = ParseInternalKey(Slice(prev_key), &prev_ikey);
-            assert(ok);
-          }
+          // This key is an earlier version of the same key in prev_key.
+          // Skip current key.
        }
-
-        if (!iterator_at_next) iter->Next();
      }
-
-      // The last key is the largest key
+      // output last key
+      builder->Add(Slice(prev_key), Slice(prev_value));
      meta->largest.DecodeFrom(Slice(prev_key));
-      SequenceNumber seqno = GetInternalKeySeqno(Slice(prev_key));
-      meta->smallest_seqno = std::min(meta->smallest_seqno, seqno);
-      meta->largest_seqno = std::max(meta->largest_seqno, seqno);

    } else {
      for (; iter->Valid(); iter->Next()) {
        Slice key = iter->key();
        meta->largest.DecodeFrom(key);
        builder->Add(key, iter->value());
-        SequenceNumber seqno = GetInternalKeySeqno(key);
-        meta->smallest_seqno = std::min(meta->smallest_seqno, seqno);
-        meta->largest_seqno = std::max(meta->largest_seqno, seqno);
      }
    }

@@ -169,10 +106,8 @@ Status BuildTable(const std::string& dbname,
    // Finish and check for file errors
    if (s.ok() && !options.disableDataSync) {
      if (options.use_fsync) {
-        StopWatch sw(env, options.statistics, TABLE_SYNC_MICROS);
        s = file->Fsync();
      } else {
-        StopWatch sw(env, options.statistics, TABLE_SYNC_MICROS);
        s = file->Sync();
      }
    }
@@ -183,7 +118,6 @@ Status BuildTable(const std::string& dbname,
    if (s.ok()) {
      // Verify that the table is usable
      Iterator* it = table_cache->NewIterator(ReadOptions(),
-                                              soptions,
                                              meta->number,
                                              meta->file_size);
      s = it->status();
@@ -204,4 +138,4 @@ Status BuildTable(const std::string& dbname,
  return s;
 }

-}  // namespace rocksdb
+}  // namespace leveldb
@@ -5,17 +5,16 @@
 #ifndef STORAGE_LEVELDB_DB_BUILDER_H_
 #define STORAGE_LEVELDB_DB_BUILDER_H_

-#include "rocksdb/comparator.h"
-#include "rocksdb/status.h"
-#include "rocksdb/types.h"
+#include "leveldb/comparator.h"
+#include "leveldb/status.h"
+#include "leveldb/types.h"

-namespace rocksdb {
+namespace leveldb {

 struct Options;
 struct FileMetaData;

 class Env;
-class EnvOptions;
 class Iterator;
 class TableCache;
 class VersionEdit;
@@ -28,7 +27,6 @@ class VersionEdit;
 extern Status BuildTable(const std::string& dbname,
                         Env* env,
                         const Options& options,
-                         const EnvOptions& soptions,
                         TableCache* table_cache,
                         Iterator* iter,
                         FileMetaData* meta,
@@ -36,6 +34,6 @@ extern Status BuildTable(const std::string& dbname,
                         const SequenceNumber newest_snapshot,
                         const SequenceNumber earliest_seqno_in_memtable);

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_BUILDER_H_
@@ -2,42 +2,42 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

-#include "rocksdb/c.h"
+#include "leveldb/c.h"

 #include <stdlib.h>
 #include <unistd.h>
-#include "rocksdb/cache.h"
-#include "rocksdb/comparator.h"
-#include "rocksdb/db.h"
-#include "rocksdb/env.h"
-#include "rocksdb/filter_policy.h"
-#include "rocksdb/iterator.h"
-#include "rocksdb/options.h"
-#include "rocksdb/status.h"
-#include "rocksdb/write_batch.h"
+#include "leveldb/cache.h"
+#include "leveldb/comparator.h"
+#include "leveldb/db.h"
+#include "leveldb/env.h"
+#include "leveldb/filter_policy.h"
+#include "leveldb/iterator.h"
+#include "leveldb/options.h"
+#include "leveldb/status.h"
+#include "leveldb/write_batch.h"

-using rocksdb::Cache;
-using rocksdb::Comparator;
-using rocksdb::CompressionType;
-using rocksdb::DB;
-using rocksdb::Env;
-using rocksdb::FileLock;
-using rocksdb::FilterPolicy;
-using rocksdb::Iterator;
-using rocksdb::Logger;
-using rocksdb::NewBloomFilterPolicy;
-using rocksdb::NewLRUCache;
-using rocksdb::Options;
-using rocksdb::RandomAccessFile;
-using rocksdb::Range;
-using rocksdb::ReadOptions;
-using rocksdb::SequentialFile;
-using rocksdb::Slice;
-using rocksdb::Snapshot;
-using rocksdb::Status;
-using rocksdb::WritableFile;
-using rocksdb::WriteBatch;
-using rocksdb::WriteOptions;
+using leveldb::Cache;
+using leveldb::Comparator;
+using leveldb::CompressionType;
+using leveldb::DB;
+using leveldb::Env;
+using leveldb::FileLock;
+using leveldb::FilterPolicy;
+using leveldb::Iterator;
+using leveldb::Logger;
+using leveldb::NewBloomFilterPolicy;
+using leveldb::NewLRUCache;
+using leveldb::Options;
+using leveldb::RandomAccessFile;
+using leveldb::Range;
+using leveldb::ReadOptions;
+using leveldb::SequentialFile;
+using leveldb::Slice;
+using leveldb::Snapshot;
+using leveldb::Status;
+using leveldb::WritableFile;
+using leveldb::WriteBatch;
+using leveldb::WriteOptions;

 using std::shared_ptr;

@@ -2,7 +2,7 @@
   Use of this source code is governed by a BSD-style license that can be
   found in the LICENSE file. See the AUTHORS file for names of contributors. */

-#include "rocksdb/c.h"
+#include "leveldb/c.h"

 #include <stddef.h>
 #include <stdio.h>
@@ -2,25 +2,25 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

-#include "rocksdb/db.h"
+#include "leveldb/db.h"

 #include <errno.h>
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-#include "rocksdb/cache.h"
-#include "rocksdb/env.h"
-#include "rocksdb/write_batch.h"
+#include "leveldb/cache.h"
+#include "leveldb/env.h"
+#include "leveldb/table.h"
+#include "leveldb/write_batch.h"
 #include "db/db_impl.h"
 #include "db/filename.h"
 #include "db/log_format.h"
 #include "db/version_set.h"
-#include "table/table.h"
 #include "util/logging.h"
 #include "util/testharness.h"
 #include "util/testutil.h"

-namespace rocksdb {
+namespace leveldb {

 static const int kValueSize = 1000;

@@ -40,7 +40,6 @@ class CorruptionTest {

    db_ = nullptr;
    options_.create_if_missing = true;
-    options_.block_size_deviation = 0; // make unit test pass for now
    Reopen();
    options_.create_if_missing = false;
  }
@@ -56,8 +55,6 @@ class CorruptionTest {
    Options opt = (options ? *options : options_);
    opt.env = &env_;
    opt.block_cache = tiny_cache_;
-    opt.block_size_deviation = 0;
-    opt.arena_block_size = 4096;
    return DB::Open(opt, dbname_, &db_);
  }

@@ -68,7 +65,7 @@ class CorruptionTest {
  void RepairDB() {
    delete db_;
    db_ = nullptr;
-    ASSERT_OK(::rocksdb::RepairDB(dbname_, options_));
+    ASSERT_OK(::leveldb::RepairDB(dbname_, options_));
  }

  void Build(int n) {
@@ -354,8 +351,8 @@ TEST(CorruptionTest, UnrelatedKeys) {
  ASSERT_EQ(Value(1000, &tmp2).ToString(), v);
 }

-}  // namespace rocksdb
+}  // namespace leveldb

 int main(int argc, char** argv) {
-  return rocksdb::test::RunAllTests();
+  return leveldb::test::RunAllTests();
 }
@@ -2,47 +2,41 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

-#include <algorithm>
-#include <string>
-#include <stdint.h>
 #include "db/db_impl.h"
 #include "db/filename.h"
+#include <string>
+#include <stdint.h>
 #include "db/version_set.h"
-#include "rocksdb/db.h"
-#include "rocksdb/env.h"
+#include "leveldb/db.h"
+#include "leveldb/env.h"
 #include "port/port.h"
 #include "util/mutexlock.h"

-namespace rocksdb {
+namespace leveldb {

 Status DBImpl::DisableFileDeletions() {
  MutexLock l(&mutex_);
  disable_delete_obsolete_files_ = true;
-  Log(options_.info_log, "File Deletions Disabled");
  return Status::OK();
 }

 Status DBImpl::EnableFileDeletions() {
  MutexLock l(&mutex_);
  disable_delete_obsolete_files_ = false;
-  Log(options_.info_log, "File Deletions Enabled");
  return Status::OK();
 }

 Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
-                            uint64_t* manifest_file_size,
-                            bool flush_memtable) {
+                            uint64_t* manifest_file_size) {

  *manifest_file_size = 0;

-  if (flush_memtable) {
-    // flush all dirty data to disk.
-    Status status =  Flush(FlushOptions());
-    if (!status.ok()) {
-      Log(options_.info_log, "Cannot Flush data %s\n",
-          status.ToString().c_str());
-      return status;
-    }
+  // flush all dirty data to disk.
+  Status status =  Flush(FlushOptions());
+  if (!status.ok()) {
+    Log(options_.info_log, "Cannot Flush data %s\n",
+        status.ToString().c_str());
+    return status;
  }

  MutexLock l(&mutex_);
@@ -51,17 +45,18 @@ Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
  std::set<uint64_t> live;
  versions_->AddLiveFilesCurrentVersion(&live);

-  ret.clear();
-  ret.reserve(live.size() + 2); //*.sst + CURRENT + MANIFEST
+  ret.resize(live.size() + 2); //*.sst + CURRENT + MANIFEST

  // create names of the live files. The names are not absolute
  // paths, instead they are relative to dbname_;
-  for (auto live_file : live) {
-    ret.push_back(TableFileName("", live_file));
+  std::set<uint64_t>::iterator it = live.begin();
+  for (unsigned int i = 0; i < live.size(); i++, it++) {
+    ret[i] = TableFileName("", *it);
  }

-  ret.push_back(CurrentFileName(""));
-  ret.push_back(DescriptorFileName("", versions_->ManifestFileNumber()));
+  ret[live.size()] = CurrentFileName("");
+  ret[live.size()+1] = DescriptorFileName("",
+                                          versions_->ManifestFileNumber());

  // find length of manifest file while holding the mutex lock
  *manifest_file_size = versions_->ManifestFileSize();
@@ -69,46 +64,4 @@ Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
  return Status::OK();
 }

-Status DBImpl::GetSortedWalFiles(VectorLogPtr& files) {
-  // First get sorted files in archive dir, then append sorted files from main
-  // dir to maintain sorted order
-
-  // list wal files in archive dir.
-  Status s;
-  std::string archivedir = ArchivalDirectory(dbname_);
-  if (env_->FileExists(archivedir)) {
-    s = AppendSortedWalsOfType(archivedir, files, kArchivedLogFile);
-    if (!s.ok()) {
-      return s;
-    }
-  }
-  // list wal files in main db dir.
-  return AppendSortedWalsOfType(dbname_, files, kAliveLogFile);
-}
-
-Status DBImpl::DeleteWalFiles(const VectorLogPtr& files) {
-  Status s;
-  std::string archivedir = ArchivalDirectory(dbname_);
-  std::string files_not_deleted;
-  for (const auto& wal : files) {
-    /* Try deleting in the dir that pathname points to for the logfile.
-       This may fail if we try to delete a log file which was live when captured
-       but is archived now. Try deleting it from archive also
-     */
-    Status st = env_->DeleteFile(dbname_ + "/" + wal->PathName());
-    if (!st.ok()) {
-      if (wal->Type() == kAliveLogFile &&
-          env_->DeleteFile(LogFileName(archivedir, wal->LogNumber())).ok()) {
-        continue;
-      }
-      files_not_deleted.append(wal->PathName());
-    }
-  }
-  if (!files_not_deleted.empty()) {
-    return Status::IOError("Deleted all requested files except: " +
-                           files_not_deleted);
-  }
-  return Status::OK();
-}
-
 }
@@ -5,17 +5,14 @@
 #ifndef STORAGE_LEVELDB_DB_DB_IMPL_H_
 #define STORAGE_LEVELDB_DB_DB_IMPL_H_

-#include <atomic>
 #include <deque>
 #include <set>
-#include <vector>
 #include "db/dbformat.h"
+#include "db/log_file.h"
 #include "db/log_writer.h"
 #include "db/snapshot.h"
-#include "rocksdb/db.h"
-#include "rocksdb/env.h"
-#include "rocksdb/memtablerep.h"
-#include "rocksdb/transaction_log.h"
+#include "leveldb/db.h"
+#include "leveldb/env.h"
 #include "port/port.h"
 #include "util/stats_logger.h"
 #include "memtablelist.h"
@@ -24,7 +21,7 @@
 #include "scribe/scribe_logger.h"
 #endif

-namespace rocksdb {
+namespace leveldb {

 class MemTable;
 class TableCache;
@@ -39,32 +36,17 @@ class DBImpl : public DB {

  // Implementations of the DB interface
  virtual Status Put(const WriteOptions&, const Slice& key, const Slice& value);
-  virtual Status Merge(const WriteOptions&, const Slice& key,
-                       const Slice& value);
  virtual Status Delete(const WriteOptions&, const Slice& key);
  virtual Status Write(const WriteOptions& options, WriteBatch* updates);
  virtual Status Get(const ReadOptions& options,
                     const Slice& key,
                     std::string* value);
-  virtual std::vector<Status> MultiGet(const ReadOptions& options,
-                                       const std::vector<Slice>& keys,
-                                       std::vector<std::string>* values);
-
-  // Returns false if key doesn't exist in the database and true if it may.
-  // If value_found is not passed in as null, then return the value if found in
-  // memory. On return, if value was found, then value_found will be set to true
-  // , otherwise false.
-  virtual bool KeyMayExist(const ReadOptions& options,
-                           const Slice& key,
-                           std::string* value,
-                           bool* value_found = nullptr);
  virtual Iterator* NewIterator(const ReadOptions&);
  virtual const Snapshot* GetSnapshot();
  virtual void ReleaseSnapshot(const Snapshot* snapshot);
  virtual bool GetProperty(const Slice& property, std::string* value);
  virtual void GetApproximateSizes(const Range* range, int n, uint64_t* sizes);
-  virtual void CompactRange(const Slice* begin, const Slice* end,
-                            bool reduce_level = false, int target_level = -1);
+  virtual void CompactRange(const Slice* begin, const Slice* end);
  virtual int NumberLevels();
  virtual int MaxMemCompactionLevel();
  virtual int Level0StopWriteTrigger();
@@ -72,21 +54,14 @@ class DBImpl : public DB {
  virtual Status DisableFileDeletions();
  virtual Status EnableFileDeletions();
  virtual Status GetLiveFiles(std::vector<std::string>&,
-                              uint64_t* manifest_file_size,
-                              bool flush_memtable = true);
-  virtual Status GetSortedWalFiles(VectorLogPtr& files);
-  virtual Status DeleteWalFiles(const VectorLogPtr& files);
+                              uint64_t* manifest_file_size);
  virtual SequenceNumber GetLatestSequenceNumber();
  virtual Status GetUpdatesSince(SequenceNumber seq_number,
                                 unique_ptr<TransactionLogIterator>* iter);
-  virtual Status DeleteFile(std::string name);
-
-  virtual void GetLiveFilesMetaData(
-    std::vector<LiveFileMetaData> *metadata);

  // Extra methods (for testing) that are not in the public DB interface

-  // Compact any files in the named level that overlap [*begin, *end]
+  // Compact any files in the named level that overlap [*begin,*end]
  void TEST_CompactRange(int level, const Slice* begin, const Slice* end);

  // Force current memtable contents to be compacted.
@@ -112,10 +87,6 @@ class DBImpl : public DB {

  // Return the current manifest file no.
  uint64_t TEST_Current_Manifest_FileNo();
-
-  // Trigger's a background call for testing.
-  void TEST_PurgeObsoleteteWAL();
-
 protected:
  Env* const env_;
  const std::string dbname_;
@@ -170,10 +141,9 @@ class DBImpl : public DB {
  // for the entire period. The second method WriteLevel0Table supports
  // concurrent flush memtables to storage.
  Status WriteLevel0TableForRecovery(MemTable* mem, VersionEdit* edit);
-  Status WriteLevel0Table(std::vector<MemTable*> &mems, VersionEdit* edit,
+  Status WriteLevel0Table(MemTable* mem, VersionEdit* edit,
                                uint64_t* filenumber);

-  uint64_t SlowdownAmount(int n, int top, int bottom);
  Status MakeRoomForWrite(bool force /* compact even if there is room? */);
  WriteBatch* BuildBatchGroup(Writer** last_writer);

@@ -188,12 +158,9 @@ class DBImpl : public DB {
  void LogDBDeployStats();

  void MaybeScheduleCompaction();
-  static void BGWorkCompaction(void* db);
-  static void BGWorkFlush(void* db);
-  void BackgroundCallCompaction();
-  void BackgroundCallFlush();
-  Status BackgroundCompaction(bool* madeProgress,DeletionState& deletion_state);
-  Status BackgroundFlush();
+  static void BGWork(void* db);
+  void BackgroundCall();
+  Status BackgroundCompaction(bool* madeProgress, DeletionState& deletion_state);
  void CleanupCompaction(CompactionState* compact);
  Status DoCompactionWork(CompactionState* compact);

@@ -216,42 +183,23 @@ class DBImpl : public DB {
  // Removes the file listed in files_to_evict from the table_cache
  void EvictObsoleteFiles(DeletionState& deletion_state);

-  Status DeleteLogFile(uint64_t number);
-
  void PurgeObsoleteWALFiles();

-  Status AppendSortedWalsOfType(const std::string& path,
-                                VectorLogPtr& log_files,
-                                WalFileType type);
+  Status ListAllWALFiles(const std::string& path,
+                         std::vector<LogFile>* logFiles,
+                         WalFileType type);

-  // Requires: all_logs should be sorted with earliest log file first
-  // Retains all log files in all_logs which contain updates with seq no.
-  // Greater Than or Equal to the requested SequenceNumber.
-  Status RetainProbableWalFiles(VectorLogPtr& all_logs,
-                                const SequenceNumber target);
-  //  return true if
-  bool CheckWalFileExistsAndEmpty(const WalFileType type,
-                                  const uint64_t number);
+  //  Find's all the log files which contain updates with seq no.
+  //  Greater Than or Equal to the requested SequenceNumber
+  Status FindProbableWALFiles(std::vector<LogFile>* const allLogs,
+                              std::vector<LogFile>* const result,
+                              const SequenceNumber target);
+
+
+  Status ReadFirstRecord(const LogFile& file, WriteBatch* const result);

-  Status ReadFirstRecord(const WalFileType type, const uint64_t number,
-                         WriteBatch* const result);

  Status ReadFirstLine(const std::string& fname, WriteBatch* const batch);
-
-  void PrintStatistics();
-
-  // dump leveldb.stats to LOG
-  void MaybeDumpStats();
-
-  // Return the minimum empty level that could hold the total data in the
-  // input level. Return the input level, if such level could not be found.
-  int FindMinimumEmptyLevelFitting(int level);
-
-  // Move the files in the input level to the target level.
-  // If target_level < 0, automatically calculate the minimum level that could
-  // hold the data set.
-  void ReFitLevel(int level, int target_level = -1);
-
  // Constant after construction
  const InternalFilterPolicy internal_filter_policy_;
  bool owns_info_log_;
@@ -266,7 +214,6 @@ class DBImpl : public DB {
  port::Mutex mutex_;
  port::AtomicPointer shutting_down_;
  port::CondVar bg_cv_;          // Signalled when background work finishes
-  std::shared_ptr<MemTableRepFactory> mem_rep_factory_;
  MemTable* mem_;
  MemTableList imm_;             // Memtable that are not changing
  uint64_t logfile_number_;
@@ -276,7 +223,7 @@ class DBImpl : public DB {

  // Queue of writers.
  std::deque<Writer*> writers_;
-  WriteBatch tmp_batch_;
+  WriteBatch* tmp_batch_;

  SnapshotList snapshots_;

@@ -287,9 +234,6 @@ class DBImpl : public DB {
  // count how many background compaction been scheduled or is running?
  int bg_compaction_scheduled_;

-  // number of background memtable flush jobs, submitted to the HIGH pool
-  int bg_flush_scheduled_;
-
  // Has a background stats log thread scheduled?
  bool bg_logstats_scheduled_;

@@ -307,7 +251,7 @@ class DBImpl : public DB {
  // Have we encountered a background error in paranoid mode?
  Status bg_error_;

-  std::unique_ptr<StatsLogger> logger_;
+  StatsLogger* logger_;

  int64_t volatile last_log_ts;

@@ -317,21 +261,11 @@ class DBImpl : public DB {
  // last time when DeleteObsoleteFiles was invoked
  uint64_t delete_obsolete_files_last_run_;

-  // last time when PurgeObsoleteWALFiles ran.
-  uint64_t purge_wal_files_last_run_;
-
-  // last time stats were dumped to LOG
-  std::atomic<uint64_t> last_stats_dump_time_microsec_;
-
  // These count the number of microseconds for which MakeRoomForWrite stalls.
  uint64_t stall_level0_slowdown_;
  uint64_t stall_memtable_compaction_;
  uint64_t stall_level0_num_files_;
  std::vector<uint64_t> stall_leveln_slowdown_;
-  uint64_t stall_level0_slowdown_count_;
-  uint64_t stall_memtable_compaction_count_;
-  uint64_t stall_level0_num_files_count_;
-  std::vector<uint64_t> stall_leveln_slowdown_count_;

  // Time at which this instance was started.
  const uint64_t started_at_;
@@ -381,20 +315,7 @@ class DBImpl : public DB {
    }
  };

-  std::vector<CompactionStats> stats_;
-
-  // Used to compute per-interval statistics
-  struct StatsSnapshot {
-    uint64_t bytes_read_;
-    uint64_t bytes_written_;
-    uint64_t bytes_new_;
-    double   seconds_up_;
-
-    StatsSnapshot() : bytes_read_(0), bytes_written_(0),
-                      bytes_new_(0), seconds_up_(0) {}
-  };
-
-  StatsSnapshot last_stats_;
+  CompactionStats* stats_;

  static const int KEEP_LOG_FILE_NUM = 1000;
  std::string db_absolute_path_;
@@ -406,15 +327,6 @@ class DBImpl : public DB {
  // Used by transaction log iterator.
  SequenceNumber last_flushed_sequence_;

-  // The options to access storage files
-  const EnvOptions storage_options_;
-
-  // A value of true temporarily disables scheduling of background work
-  bool bg_work_gate_closed_;
-
-  // Guard against multiple concurrent refitting
-  bool refitting_level_;
-
  // No copying allowed
  DBImpl(const DBImpl&);
  void operator=(const DBImpl&);
@@ -422,19 +334,9 @@ class DBImpl : public DB {
  // dump the delayed_writes_ to the log file and reset counter.
  void DelayLoggingAndReset();

-  // Return the earliest snapshot where seqno is visible.
-  // Store the snapshot right before that, if any, in prev_snapshot
-  inline SequenceNumber findEarliestVisibleSnapshot(
-    SequenceNumber in,
-    std::vector<SequenceNumber>& snapshots,
-    SequenceNumber* prev_snapshot);
-
-  // Function that Get and KeyMayExist call with no_io true or false
-  // Note: 'value_found' from KeyMayExist propagates here
-  Status GetImpl(const ReadOptions& options,
-                 const Slice& key,
-                 std::string* value,
-                 bool* value_found = nullptr);
+  // find the earliest snapshot where seqno is visible
+  inline SequenceNumber findEarliestVisibleSnapshot(SequenceNumber in,
+    std::vector<SequenceNumber>& snapshots);
 };

 // Sanitize db options.  The caller should delete result.info_log if
@@ -444,6 +346,6 @@ extern Options SanitizeOptions(const std::string& db,
                               const InternalFilterPolicy* ipolicy,
                               const Options& src);

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_DB_IMPL_H_
@@ -21,20 +21,20 @@
 #include "db/table_cache.h"
 #include "db/version_set.h"
 #include "db/write_batch_internal.h"
-#include "rocksdb/db.h"
-#include "rocksdb/env.h"
-#include "rocksdb/status.h"
-#include "rocksdb/table_builder.h"
+#include "leveldb/db.h"
+#include "leveldb/env.h"
+#include "leveldb/status.h"
+#include "leveldb/table.h"
+#include "leveldb/table_builder.h"
 #include "port/port.h"
 #include "table/block.h"
 #include "table/merger.h"
-#include "table/table.h"
 #include "table/two_level_iterator.h"
 #include "util/coding.h"
 #include "util/logging.h"
 #include "util/build_version.h"

-namespace rocksdb {
+namespace leveldb {

 DBImplReadOnly::DBImplReadOnly(const Options& options,
    const std::string& dbname)
@@ -53,12 +53,11 @@ Status DBImplReadOnly::Get(const ReadOptions& options,
  MemTable* mem = GetMemTable();
  Version* current = versions_->current();
  SequenceNumber snapshot = versions_->LastSequence();
-  std::deque<std::string> merge_operands;
  LookupKey lkey(key, snapshot);
-  if (mem->Get(lkey, value, &s, &merge_operands, options_)) {
+  if (mem->Get(lkey, value, &s)) {
  } else {
    Version::GetStats stats;
-    current->Get(options, lkey, value, &s, &merge_operands, &stats, options_);
+    s = current->Get(options, lkey, value, &stats);
  }
  return s;
 }
@@ -67,7 +66,7 @@ Iterator* DBImplReadOnly::NewIterator(const ReadOptions& options) {
  SequenceNumber latest_snapshot;
  Iterator* internal_iter = NewInternalIterator(options, &latest_snapshot);
  return NewDBIterator(
-    &dbname_, env_, options_,  user_comparator(),internal_iter,
+      &dbname_, env_, user_comparator(), internal_iter,
      (options.snapshot != nullptr
      ? reinterpret_cast<const SnapshotImpl*>(options.snapshot)->number_
      : latest_snapshot));
@@ -12,8 +12,8 @@
 #include "db/dbformat.h"
 #include "db/log_writer.h"
 #include "db/snapshot.h"
-#include "rocksdb/db.h"
-#include "rocksdb/env.h"
+#include "leveldb/db.h"
+#include "leveldb/env.h"
 #include "port/port.h"
 #include "util/stats_logger.h"

@@ -21,7 +21,7 @@
 #include "scribe/scribe_logger.h"
 #endif

-namespace rocksdb {
+namespace leveldb {

 class DBImplReadOnly : public DBImpl {
 public:
@@ -32,26 +32,18 @@ public:
 virtual Status Get(const ReadOptions& options,
                    const Slice& key,
                    std::string* value);
-
- // TODO: Implement ReadOnly MultiGet?
-
 virtual Iterator* NewIterator(const ReadOptions&);

 virtual Status Put(const WriteOptions&, const Slice& key, const Slice& value) {
   return Status::NotSupported("Not supported operation in read only mode.");
 }
- virtual Status Merge(const WriteOptions&, const Slice& key,
-                      const Slice& value) {
-   return Status::NotSupported("Not supported operation in read only mode.");
- }
 virtual Status Delete(const WriteOptions&, const Slice& key) {
   return Status::NotSupported("Not supported operation in read only mode.");
 }
 virtual Status Write(const WriteOptions& options, WriteBatch* updates) {
   return Status::NotSupported("Not supported operation in read only mode.");
 }
- virtual void CompactRange(const Slice* begin, const Slice* end,
-                           bool reduce_level = false, int target_level = -1) {
+ virtual void CompactRange(const Slice* begin, const Slice* end) {
 }
 virtual Status DisableFileDeletions() {
   return Status::NotSupported("Not supported operation in read only mode.");
@@ -60,8 +52,7 @@ public:
   return Status::NotSupported("Not supported operation in read only mode.");
 }
 virtual Status GetLiveFiles(std::vector<std::string>&,
-                             uint64_t* manifest_file_size,
-                             bool flush_memtable = true) {
+                             uint64_t* manifest_file_size) {
   return Status::NotSupported("Not supported operation in read only mode.");
 }
 virtual Status Flush(const FlushOptions& options) {
@@ -3,21 +3,16 @@
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

 #include "db/db_iter.h"
-#include <stdexcept>
-#include <deque>

 #include "db/filename.h"
 #include "db/dbformat.h"
-#include "rocksdb/env.h"
-#include "rocksdb/options.h"
-#include "rocksdb/iterator.h"
-#include "rocksdb/merge_operator.h"
+#include "leveldb/env.h"
+#include "leveldb/iterator.h"
 #include "port/port.h"
 #include "util/logging.h"
 #include "util/mutexlock.h"
-#include "util/perf_context_imp.h"

-namespace rocksdb {
+namespace leveldb {

 #if 0
 static void DumpInternalIter(Iterator* iter) {
@@ -41,7 +36,6 @@ namespace {
 // numbers, deletion markers, overwrites, etc.
 class DBIter: public Iterator {
 public:
-  // The following is grossly complicated. TODO: clean it up
  // Which direction is the iterator currently moving?
  // (1) When moving forward, the internal iterator is positioned at
  //     the exact entry that yields this->key(), this->value()
@@ -52,35 +46,27 @@ class DBIter: public Iterator {
    kReverse
  };

-  DBIter(const std::string* dbname, Env* env, const Options& options,
+  DBIter(const std::string* dbname, Env* env,
         const Comparator* cmp, Iterator* iter, SequenceNumber s)
      : dbname_(dbname),
        env_(env),
-        logger_(options.info_log),
        user_comparator_(cmp),
-        user_merge_operator_(options.merge_operator.get()),
        iter_(iter),
        sequence_(s),
        direction_(kForward),
-        valid_(false),
-        current_entry_is_merged_(false),
-        statistics_(options.statistics) {
-    RecordTick(statistics_, NO_ITERATORS, 1);
-    max_skip_ = options.max_sequential_skip_in_iterations;
+        valid_(false) {
  }
  virtual ~DBIter() {
-    RecordTick(statistics_, NO_ITERATORS, -1);
    delete iter_;
  }
  virtual bool Valid() const { return valid_; }
  virtual Slice key() const {
    assert(valid_);
-    return saved_key_;
+    return (direction_ == kForward) ? ExtractUserKey(iter_->key()) : saved_key_;
  }
  virtual Slice value() const {
    assert(valid_);
-    return (direction_ == kForward && !current_entry_is_merged_) ?
-      iter_->value() : saved_value_;
+    return (direction_ == kForward) ? iter_->value() : saved_value_;
  }
  virtual Status status() const {
    if (status_.ok()) {
@@ -97,10 +83,9 @@ class DBIter: public Iterator {
  virtual void SeekToLast();

 private:
-  void FindNextUserEntry(bool skipping);
+  void FindNextUserEntry(bool skipping, std::string* skip);
  void FindPrevUserEntry();
  bool ParseKey(ParsedInternalKey* key);
-  void MergeValuesNewToOld();

  inline void SaveKey(const Slice& k, std::string* dst) {
    dst->assign(k.data(), k.size());
@@ -117,21 +102,15 @@ class DBIter: public Iterator {

  const std::string* const dbname_;
  Env* const env_;
-  shared_ptr<Logger> logger_;
  const Comparator* const user_comparator_;
-  const MergeOperator* const user_merge_operator_;
  Iterator* const iter_;
  SequenceNumber const sequence_;

  Status status_;
  std::string saved_key_;     // == current key when direction_==kReverse
  std::string saved_value_;   // == current raw value when direction_==kReverse
-  std::string skip_key_;
  Direction direction_;
  bool valid_;
-  bool current_entry_is_merged_;
-  std::shared_ptr<Statistics> statistics_;
-  uint64_t max_skip_;

  // No copying allowed
  DBIter(const DBIter&);
@@ -141,8 +120,6 @@ class DBIter: public Iterator {
 inline bool DBIter::ParseKey(ParsedInternalKey* ikey) {
  if (!ParseInternalKey(iter_->key(), ikey)) {
    status_ = Status::Corruption("corrupted internal key in DBIter");
-    Log(logger_, "corrupted internal key in DBIter: %s",
-        iter_->key().ToString(true).c_str());
    return false;
  } else {
    return true;
@@ -169,173 +146,47 @@ void DBIter::Next() {
    }
  }

-  // If the current value is merged, we might already hit end of iter_
-  if (!iter_->Valid()) {
-    valid_ = false;
-    return;
-  }
-  FindNextUserEntry(true /* skipping the current user key */);
+  // Temporarily use saved_key_ as storage for key to skip.
+  std::string* skip = &saved_key_;
+  SaveKey(ExtractUserKey(iter_->key()), skip);
+  FindNextUserEntry(true, skip);
 }

-
-// PRE: saved_key_ has the current user key if skipping
-// POST: saved_key_ should have the next user key if valid_,
-//       if the current entry is a result of merge
-//           current_entry_is_merged_ => true
-//           saved_value_             => the merged value
-//
-// NOTE: In between, saved_key_ can point to a user key that has
-//       a delete marker
-void DBIter::FindNextUserEntry(bool skipping) {
+void DBIter::FindNextUserEntry(bool skipping, std::string* skip) {
  // Loop until we hit an acceptable entry to yield
  assert(iter_->Valid());
  assert(direction_ == kForward);
-  current_entry_is_merged_ = false;
-  uint64_t num_skipped = 0;
  do {
    ParsedInternalKey ikey;
    if (ParseKey(&ikey) && ikey.sequence <= sequence_) {
-      if (skipping &&
-          user_comparator_->Compare(ikey.user_key, saved_key_) <= 0) {
-        num_skipped++; // skip this entry
-        BumpPerfCount(&perf_context.internal_key_skipped_count);
-      } else {
-        skipping = false;
-        switch (ikey.type) {
-          case kTypeDeletion:
-            // Arrange to skip all upcoming entries for this key since
-            // they are hidden by this deletion.
-            SaveKey(ikey.user_key, &saved_key_);
-            skipping = true;
-            num_skipped = 0;
-            BumpPerfCount(&perf_context.internal_delete_skipped_count);
-            break;
-          case kTypeValue:
-            valid_ = true;
-            SaveKey(ikey.user_key, &saved_key_);
-            return;
-          case kTypeMerge:
-            // By now, we are sure the current ikey is going to yield a value
-            SaveKey(ikey.user_key, &saved_key_);
-            current_entry_is_merged_ = true;
-            valid_ = true;
-            MergeValuesNewToOld();  // Go to a different state machine
-            return;
-          case kTypeLogData:
-            assert(false);
-            break;
-        }
-      }
-    }
-    // If we have sequentially iterated via numerous keys and still not
-    // found the next user-key, then it is better to seek so that we can
-    // avoid too many key comparisons. We seek to the last occurence of
-    // our current key by looking for sequence number 0.
-    if (skipping && num_skipped > max_skip_) {
-      num_skipped = 0;
-      std::string last_key;
-      AppendInternalKey(&last_key,
-        ParsedInternalKey(Slice(saved_key_), 0, kValueTypeForSeek));
-      iter_->Seek(last_key);
-      RecordTick(statistics_, NUMBER_OF_RESEEKS_IN_ITERATION);
-    } else {
-      iter_->Next();
-    }
-  } while (iter_->Valid());
-  valid_ = false;
-}
-
-// Merge values of the same user key starting from the current iter_ position
-// Scan from the newer entries to older entries.
-// PRE: iter_->key() points to the first merge type entry
-//      saved_key_ stores the user key
-// POST: saved_value_ has the merged value for the user key
-//       iter_ points to the next entry (or invalid)
-void DBIter::MergeValuesNewToOld() {
-  if (!user_merge_operator_) {
-    Log(logger_, "Options::merge_operator is null.");
-    throw std::logic_error("DBIter::MergeValuesNewToOld() with"
-                           " Options::merge_operator null");
-  }
-
-  // Start the merge process by pushing the first operand
-  std::deque<std::string> operands;
-  operands.push_front(iter_->value().ToString());
-
-  std::string merge_result;   // Temporary string to hold merge result later
-  ParsedInternalKey ikey;
-  for (iter_->Next(); iter_->Valid(); iter_->Next()) {
-    if (!ParseKey(&ikey)) {
-      // skip corrupted key
-      continue;
-    }
-
-    if (user_comparator_->Compare(ikey.user_key, saved_key_) != 0) {
-      // hit the next user key, stop right here
-      break;
-    }
-
-    if (kTypeDeletion == ikey.type) {
-      // hit a delete with the same user key, stop right here
-      // iter_ is positioned after delete
-      iter_->Next();
-      break;
-    }
-
-    if (kTypeValue == ikey.type) {
-      // hit a put, merge the put value with operands and store the
-      // final result in saved_value_. We are done!
-      // ignore corruption if there is any.
-      const Slice value = iter_->value();
-      user_merge_operator_->FullMerge(ikey.user_key, &value, operands,
-                                      &saved_value_, logger_.get());
-      // iter_ is positioned after put
-      iter_->Next();
-      return;
-    }
-
-    if (kTypeMerge == ikey.type) {
-      // hit a merge, add the value as an operand and run associative merge.
-      // when complete, add result to operands and continue.
-      const Slice& value = iter_->value();
-      operands.push_front(value.ToString());
-      while(operands.size() >= 2) {
-        // Call user associative-merge until it returns false
-        if (user_merge_operator_->PartialMerge(ikey.user_key,
-                                               Slice(operands[0]),
-                                               Slice(operands[1]),
-                                               &merge_result,
-                                               logger_.get())) {
-          operands.pop_front();
-          swap(operands.front(), merge_result);
-        } else {
-          // Associative merge returns false ==> stack the operands
+      switch (ikey.type) {
+        case kTypeDeletion:
+          // Arrange to skip all upcoming entries for this key since
+          // they are hidden by this deletion.
+          SaveKey(ikey.user_key, skip);
+          skipping = true;
+          break;
+        case kTypeValue:
+          if (skipping &&
+              user_comparator_->Compare(ikey.user_key, *skip) <= 0) {
+            // Entry hidden
+          } else {
+            valid_ = true;
+            saved_key_.clear();
+            return;
+          }
          break;
-        }
      }
-
    }
-  }
-
-  // we either exhausted all internal keys under this user key, or hit
-  // a deletion marker.
-  // feed null as the existing value to the merge operator, such that
-  // client can differentiate this scenario and do things accordingly.
-  user_merge_operator_->FullMerge(saved_key_, nullptr, operands,
-                                  &saved_value_, logger_.get());
+    iter_->Next();
+  } while (iter_->Valid());
+  saved_key_.clear();
+  valid_ = false;
 }

 void DBIter::Prev() {
  assert(valid_);

-  // Throw an exception now if merge_operator is provided
-  // TODO: support backward iteration
-  if (user_merge_operator_) {
-    Log(logger_, "Prev not supported yet if merge_operator is provided");
-    throw std::logic_error("DBIter::Prev backward iteration not supported"
-                           " if merge_operator is provided");
-  }
-
  if (direction_ == kForward) {  // Switch directions?
    // iter_ is pointing at the current entry.  Scan backwards until
    // the key changes so we can use the normal reverse scanning code.
@@ -362,7 +213,6 @@ void DBIter::Prev() {

 void DBIter::FindPrevUserEntry() {
  assert(direction_ == kReverse);
-  uint64_t num_skipped = 0;

  ValueType value_type = kTypeDeletion;
  if (iter_->Valid()) {
@@ -388,22 +238,7 @@ void DBIter::FindPrevUserEntry() {
          saved_value_.assign(raw_value.data(), raw_value.size());
        }
      }
-      num_skipped++;
-      // If we have sequentially iterated via numerous keys and still not
-      // found the prev user-key, then it is better to seek so that we can
-      // avoid too many key comparisons. We seek to the first occurence of
-      // our current key by looking for max sequence number.
-      if (num_skipped > max_skip_) {
-        num_skipped = 0;
-        std::string last_key;
-        AppendInternalKey(&last_key,
-          ParsedInternalKey(Slice(saved_key_), kMaxSequenceNumber,
-                            kValueTypeForSeek));
-        iter_->Seek(last_key);
-        RecordTick(statistics_, NUMBER_OF_RESEEKS_IN_ITERATION);
-      } else {
-        iter_->Prev();
-      }
+      iter_->Prev();
    } while (iter_->Valid());
  }

@@ -426,7 +261,7 @@ void DBIter::Seek(const Slice& target) {
      &saved_key_, ParsedInternalKey(target, sequence_, kValueTypeForSeek));
  iter_->Seek(saved_key_);
  if (iter_->Valid()) {
-    FindNextUserEntry(false /*not skipping */);
+    FindNextUserEntry(false, &saved_key_ /* temporary storage */);
  } else {
    valid_ = false;
  }
@@ -437,21 +272,13 @@ void DBIter::SeekToFirst() {
  ClearSavedValue();
  iter_->SeekToFirst();
  if (iter_->Valid()) {
-    FindNextUserEntry(false /* not skipping */);
+    FindNextUserEntry(false, &saved_key_ /* temporary storage */);
  } else {
    valid_ = false;
  }
 }

 void DBIter::SeekToLast() {
-  // Throw an exception for now if merge_operator is provided
-  // TODO: support backward iteration
-  if (user_merge_operator_) {
-    Log(logger_, "SeekToLast not supported yet if merge_operator is provided");
-    throw std::logic_error("DBIter::SeekToLast: backward iteration not"
-                           " supported if merge_operator is provided");
-  }
-
  direction_ = kReverse;
  ClearSavedValue();
  iter_->SeekToLast();
@@ -463,12 +290,10 @@ void DBIter::SeekToLast() {
 Iterator* NewDBIterator(
    const std::string* dbname,
    Env* env,
-    const Options& options,
-    const Comparator *user_key_comparator,
+    const Comparator* user_key_comparator,
    Iterator* internal_iter,
    const SequenceNumber& sequence) {
-  return new DBIter(dbname, env, options, user_key_comparator,
-                    internal_iter, sequence);
+  return new DBIter(dbname, env, user_key_comparator, internal_iter, sequence);
 }

-}  // namespace rocksdb
+}  // namespace leveldb
@@ -6,10 +6,10 @@
 #define STORAGE_LEVELDB_DB_DB_ITER_H_

 #include <stdint.h>
-#include "rocksdb/db.h"
+#include "leveldb/db.h"
 #include "db/dbformat.h"

-namespace rocksdb {
+namespace leveldb {

 // Return a new iterator that converts internal keys (yielded by
 // "*internal_iter") that were live at the specified "sequence" number
@@ -17,11 +17,10 @@ namespace rocksdb {
 extern Iterator* NewDBIterator(
    const std::string* dbname,
    Env* env,
-    const Options& options,
-    const Comparator *user_key_comparator,
+    const Comparator* user_key_comparator,
    Iterator* internal_iter,
    const SequenceNumber& sequence);

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_DB_ITER_H_
@@ -8,15 +8,14 @@
 #include <cassert>
 #include <stdlib.h>
 #include <vector>
-#include <memory>

-#include "rocksdb/statistics.h"
+#include "leveldb/statistics.h"
 #include "util/histogram.h"
 #include "port/port.h"
 #include "util/mutexlock.h"


-namespace rocksdb {
+namespace leveldb {

 class DBStatistics: public Statistics {
 public:
@@ -30,11 +29,6 @@ class DBStatistics: public Statistics {
    return allTickers_[tickerType].getCount();
  }

-  virtual void setTickerCount(Tickers tickerType, uint64_t count) {
-    assert(tickerType < TICKER_ENUM_MAX);
-    allTickers_[tickerType].setTickerCount(count);
-  }
-
  virtual void recordTick(Tickers tickerType, uint64_t count) {
    assert(tickerType < TICKER_ENUM_MAX);
    allTickers_[tickerType].recordTick(count);
@@ -45,6 +39,11 @@ class DBStatistics: public Statistics {
    allHistograms_[histogramType].Add(value);
  }

+  virtual void measureTime(Histograms histogramType, double value) {
+    assert(histogramType < HISTOGRAM_ENUM_MAX);
+    allHistograms_[histogramType].Add(value);
+  }
+
  virtual void histogramData(Histograms histogramType,
                             HistogramData * const data) {
    assert(histogramType < HISTOGRAM_ENUM_MAX);
@@ -54,11 +53,8 @@ class DBStatistics: public Statistics {
  std::vector<Ticker> allTickers_;
  std::vector<HistogramImpl> allHistograms_;
 };
-
-std::shared_ptr<Statistics> CreateDBStatistics() {
-  return std::make_shared<DBStatistics>();
-}
-
-} // namespace rocksdb
+} // namespace leveldb

 #endif // LEVELDB_STORAGE_DB_DB_STATISTICS_H_
+
+
@@ -7,12 +7,12 @@
 #include <stdint.h>
 #include <stdio.h>
 #include "db/version_set.h"
-#include "rocksdb/db.h"
-#include "rocksdb/env.h"
+#include "leveldb/db.h"
+#include "leveldb/env.h"
 #include "port/port.h"
 #include "util/mutexlock.h"

-namespace rocksdb {
+namespace leveldb {

 void DBImpl::MaybeScheduleLogDBDeployStats() {

@@ -6,9 +6,8 @@
 #include "db/dbformat.h"
 #include "port/port.h"
 #include "util/coding.h"
-#include "util/perf_context_imp.h"

-namespace rocksdb {
+namespace leveldb {

 static uint64_t PackSequenceAndType(uint64_t seq, ValueType t) {
  assert(seq <= kMaxSequenceNumber);
@@ -45,7 +44,7 @@ std::string InternalKey::DebugString(bool hex) const {
 }

 const char* InternalKeyComparator::Name() const {
-  return name_.c_str();
+  return "leveldb.InternalKeyComparator";
 }

 int InternalKeyComparator::Compare(const Slice& akey, const Slice& bkey) const {
@@ -54,7 +53,6 @@ int InternalKeyComparator::Compare(const Slice& akey, const Slice& bkey) const {
  //    decreasing sequence number
  //    decreasing type (though sequence# should be enough to disambiguate)
  int r = user_comparator_->Compare(ExtractUserKey(akey), ExtractUserKey(bkey));
-  BumpPerfCount(&perf_context.user_key_comparison_count);
  if (r == 0) {
    const uint64_t anum = DecodeFixed64(akey.data() + akey.size() - 8);
    const uint64_t bnum = DecodeFixed64(bkey.data() + bkey.size() - 8);
@@ -139,4 +137,4 @@ LookupKey::LookupKey(const Slice& user_key, SequenceNumber s) {
  end_ = dst;
 }

-}  // namespace rocksdb
+}  // namespace leveldb
@@ -6,16 +6,16 @@
 #define STORAGE_LEVELDB_DB_FORMAT_H_

 #include <stdio.h>
-#include "rocksdb/comparator.h"
-#include "rocksdb/db.h"
-#include "rocksdb/filter_policy.h"
-#include "rocksdb/slice.h"
-#include "rocksdb/table_builder.h"
-#include "rocksdb/types.h"
+#include "leveldb/comparator.h"
+#include "leveldb/db.h"
+#include "leveldb/filter_policy.h"
+#include "leveldb/slice.h"
+#include "leveldb/table_builder.h"
+#include "leveldb/types.h"
 #include "util/coding.h"
 #include "util/logging.h"

-namespace rocksdb {
+namespace leveldb {

 class InternalKey;

@@ -24,9 +24,7 @@ class InternalKey;
 // data structures.
 enum ValueType {
  kTypeDeletion = 0x0,
-  kTypeValue = 0x1,
-  kTypeMerge = 0x2,
-  kTypeLogData = 0x3
+  kTypeValue = 0x1
 };
 // kValueTypeForSeek defines the ValueType that should be passed when
 // constructing a ParsedInternalKey object for seeking to a particular
@@ -34,7 +32,7 @@ enum ValueType {
 // and the value type is embedded as the low 8 bits in the sequence
 // number in internal keys, we need to use the highest-numbered
 // ValueType, not the lowest).
-static const ValueType kValueTypeForSeek = kTypeMerge;
+static const ValueType kValueTypeForSeek = kTypeValue;

 // We leave eight bits empty at the bottom so a type and sequence#
 // can be packed together into 64-bits.
@@ -87,13 +85,8 @@ inline ValueType ExtractValueType(const Slice& internal_key) {
 class InternalKeyComparator : public Comparator {
 private:
  const Comparator* user_comparator_;
-  std::string name_;
 public:
-  explicit InternalKeyComparator(const Comparator* c) : user_comparator_(c),
-    name_("leveldb.InternalKeyComparator:" +
-          std::string(user_comparator_->Name())) {
-  }
-
+  explicit InternalKeyComparator(const Comparator* c) : user_comparator_(c) { }
  virtual const char* Name() const;
  virtual int Compare(const Slice& a, const Slice& b) const;
  virtual void FindShortestSeparator(
@@ -161,7 +154,7 @@ inline bool ParseInternalKey(const Slice& internal_key,
  result->sequence = num >> 8;
  result->type = static_cast<ValueType>(c);
  result->user_key = Slice(internal_key.data(), n - 8);
-  return (c <= static_cast<unsigned char>(kValueTypeForSeek));
+  return (c <= static_cast<unsigned char>(kTypeValue));
 }

 // Update the sequence number in the internal key
@@ -174,15 +167,6 @@ inline void UpdateInternalKey(char* internal_key,
  EncodeFixed64(seqtype, newval);
 }

-// Get the sequence number from the internal key
-inline uint64_t GetInternalKeySeqno(const Slice& internal_key) {
-  const size_t n = internal_key.size();
-  assert(n >= 8);
-  uint64_t num = DecodeFixed64(internal_key.data() + n - 8);
-  return num >> 8;
-}
-
-
 // A helper class useful for DBImpl::Get()
 class LookupKey {
 public:
@@ -223,6 +207,6 @@ inline LookupKey::~LookupKey() {
  if (start_ != space_) delete[] start_;
 }

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_FORMAT_H_
@@ -6,7 +6,7 @@
 #include "util/logging.h"
 #include "util/testharness.h"

-namespace rocksdb {
+namespace leveldb {

 static std::string IKey(const std::string& user_key,
                        uint64_t seq,
@@ -105,8 +105,8 @@ TEST(FormatTest, InternalKeyShortestSuccessor) {
            ShortSuccessor(IKey("\xff\xff", 100, kTypeValue)));
 }

-}  // namespace rocksdb
+}  // namespace leveldb

 int main(int argc, char** argv) {
-  return rocksdb::test::RunAllTests();
+  return leveldb::test::RunAllTests();
 }
@@ -1,188 +0,0 @@
-// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file. See the AUTHORS file for names of contributors.
-
-#include "rocksdb/db.h"
-#include "db/db_impl.h"
-#include "db/filename.h"
-#include "db/version_set.h"
-#include "db/write_batch_internal.h"
-#include "util/testharness.h"
-#include "util/testutil.h"
-#include "boost/lexical_cast.hpp"
-#include "rocksdb/env.h"
-#include <vector>
-#include <boost/algorithm/string.hpp>
-#include <stdlib.h>
-#include <map>
-
-namespace rocksdb {
-
-class DeleteFileTest {
- public:
-  std::string dbname_;
-  Options options_;
-  DB* db_;
-  Env* env_;
-  int numlevels_;
-
-  DeleteFileTest() {
-    db_ = nullptr;
-    env_ = Env::Default();
-    options_.write_buffer_size = 1024*1024*1000;
-    options_.target_file_size_base = 1024*1024*1000;
-    options_.max_bytes_for_level_base = 1024*1024*1000;
-    dbname_ = test::TmpDir() + "/deletefile_test";
-    DestroyDB(dbname_, options_);
-    numlevels_ = 7;
-    ASSERT_OK(ReopenDB(true));
-  }
-
-  Status ReopenDB(bool create) {
-    delete db_;
-    if (create) {
-      DestroyDB(dbname_, options_);
-    }
-    db_ = nullptr;
-    options_.create_if_missing = create;
-    return DB::Open(options_, dbname_, &db_);
-  }
-
-  void CloseDB() {
-    delete db_;
-  }
-
-  void AddKeys(int numkeys, int startkey = 0) {
-    WriteOptions options;
-    options.sync = false;
-    ReadOptions roptions;
-    for (int i = startkey; i < (numkeys + startkey) ; i++) {
-      std::string temp = boost::lexical_cast<std::string>(i);
-      Slice key(temp);
-      Slice value(temp);
-      ASSERT_OK(db_->Put(options, key, value));
-    }
-  }
-
-  int numKeysInLevels(
-    std::vector<LiveFileMetaData> &metadata,
-    std::vector<int> *keysperlevel = nullptr) {
-
-    if (keysperlevel != nullptr) {
-      keysperlevel->resize(numlevels_);
-    }
-
-    int numKeys = 0;
-    for (size_t i = 0; i < metadata.size(); i++) {
-      int startkey = atoi(metadata[i].smallestkey.c_str());
-      int endkey = atoi(metadata[i].largestkey.c_str());
-      int numkeysinfile = (endkey - startkey + 1);
-      numKeys += numkeysinfile;
-      if (keysperlevel != nullptr) {
-        (*keysperlevel)[(int)metadata[i].level] += numkeysinfile;
-      }
-      fprintf(stderr, "level %d name %s smallest %s largest %s\n",
-              metadata[i].level, metadata[i].name.c_str(),
-              metadata[i].smallestkey.c_str(),
-              metadata[i].largestkey.c_str());
-    }
-    return numKeys;
-  }
-
-  void CreateTwoLevels() {
-    AddKeys(50000, 10000);
-    DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-    ASSERT_OK(dbi->TEST_CompactMemTable());
-    ASSERT_OK(dbi->TEST_WaitForCompactMemTable());
-
-    AddKeys(50000, 10000);
-    ASSERT_OK(dbi->TEST_CompactMemTable());
-    ASSERT_OK(dbi->TEST_WaitForCompactMemTable());
-  }
-
-};
-
-TEST(DeleteFileTest, AddKeysAndQueryLevels) {
-  CreateTwoLevels();
-  std::vector<LiveFileMetaData> metadata;
-  std::vector<int> keysinlevel;
-  db_->GetLiveFilesMetaData(&metadata);
-
-  std::string level1file = "";
-  int level1keycount = 0;
-  std::string level2file = "";
-  int level2keycount = 0;
-  int level1index = 0;
-  int level2index = 1;
-
-  ASSERT_EQ((int)metadata.size(), 2);
-  if (metadata[0].level == 2) {
-    level1index = 1;
-    level2index = 0;
-  }
-
-  level1file = metadata[level1index].name;
-  int startkey = atoi(metadata[level1index].smallestkey.c_str());
-  int endkey = atoi(metadata[level1index].largestkey.c_str());
-  level1keycount = (endkey - startkey + 1);
-  level2file = metadata[level2index].name;
-  startkey = atoi(metadata[level2index].smallestkey.c_str());
-  endkey = atoi(metadata[level2index].largestkey.c_str());
-  level2keycount = (endkey - startkey + 1);
-
-  // COntrolled setup. Levels 1 and 2 should both have 50K files.
-  // This is a little fragile as it depends on the current
-  // compaction heuristics.
-  ASSERT_EQ(level1keycount, 50000);
-  ASSERT_EQ(level2keycount, 50000);
-
-  Status status = db_->DeleteFile("0.sst");
-  ASSERT_TRUE(status.IsInvalidArgument());
-
-  // intermediate level files cannot be deleted.
-  status = db_->DeleteFile(level1file);
-  ASSERT_TRUE(status.IsInvalidArgument());
-
-  // Lowest level file deletion should succeed.
-  ASSERT_OK(db_->DeleteFile(level2file));
-
-  CloseDB();
-}
-
-
-TEST(DeleteFileTest, DeleteFileWithIterator) {
-  CreateTwoLevels();
-  ReadOptions options;
-  Iterator* it = db_->NewIterator(options);
-  std::vector<LiveFileMetaData> metadata;
-  db_->GetLiveFilesMetaData(&metadata);
-
-  std::string level2file = "";
-
-  ASSERT_EQ((int)metadata.size(), 2);
-  if (metadata[0].level == 1) {
-    level2file = metadata[1].name;
-  } else {
-    level2file = metadata[0].name;
-  }
-
-  Status status = db_->DeleteFile(level2file);
-  fprintf(stdout, "Deletion status %s: %s\n",
-          level2file.c_str(), status.ToString().c_str());
-  ASSERT_TRUE(status.ok());
-  it->SeekToFirst();
-  int numKeysIterated = 0;
-  while(it->Valid()) {
-    numKeysIterated++;
-    it->Next();
-  }
-  ASSERT_EQ(numKeysIterated, 50000);
-  delete it;
-  CloseDB();
-}
-} //namespace rocksdb
-
-int main(int argc, char** argv) {
-  return rocksdb::test::RunAllTests();
-}
-
@@ -7,10 +7,10 @@
 #include <ctype.h>
 #include <stdio.h>
 #include "db/dbformat.h"
-#include "rocksdb/env.h"
+#include "leveldb/env.h"
 #include "util/logging.h"

-namespace rocksdb {
+namespace leveldb {

 // Given a path, flatten the path name by replacing all chars not in
 // {[0-9,a-z,A-Z,-,_,.]} with _. And append '\0' at the end.
@@ -62,7 +62,7 @@ std::string ArchivalDirectory(const std::string& dbname) {
 }
 std::string ArchivedLogFileName(const std::string& name, uint64_t number) {
  assert(number > 0);
-  return MakeFileName(name + "/" + ARCHIVAL_DIR, number, "log");
+  return MakeFileName(name + "/archive", number, "log");
 }

 std::string TableFileName(const std::string& name, uint64_t number) {
@@ -130,14 +130,10 @@ std::string MetaDatabaseName(const std::string& dbname, uint64_t number) {
 //    dbname/MANIFEST-[0-9]+
 //    dbname/[0-9]+.(log|sst)
 //    dbname/METADB-[0-9]+
-//    Disregards / at the beginning
 bool ParseFileName(const std::string& fname,
                   uint64_t* number,
                   FileType* type) {
  Slice rest(fname);
-  if (fname.length() > 1 && fname[0] == '/') {
-    rest.remove_prefix(1);
-  }
  if (rest == "CURRENT") {
    *number = 0;
    *type = kCurrentFile;
@@ -218,4 +214,4 @@ Status SetCurrentFile(Env* env, const std::string& dbname,
  return s;
 }

-}  // namespace rocksdb
+}  // namespace leveldb
@@ -9,11 +9,11 @@

 #include <stdint.h>
 #include <string>
-#include "rocksdb/slice.h"
-#include "rocksdb/status.h"
+#include "leveldb/slice.h"
+#include "leveldb/status.h"
 #include "port/port.h"

-namespace rocksdb {
+namespace leveldb {

 class Env;

@@ -92,6 +92,6 @@ extern Status SetCurrentFile(Env* env, const std::string& dbname,
                             uint64_t descriptor_number);


-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_FILENAME_H_
@@ -9,7 +9,7 @@
 #include "util/logging.h"
 #include "util/testharness.h"

-namespace rocksdb {
+namespace leveldb {

 class FileNameTest { };

@@ -128,8 +128,8 @@ TEST(FileNameTest, Construction) {
  ASSERT_EQ(kMetaDatabase, type);
 }

-}  // namespace rocksdb
+}  // namespace leveldb

 int main(int argc, char** argv) {
-  return rocksdb::test::RunAllTests();
+  return leveldb::test::RunAllTests();
 }
@@ -0,0 +1,48 @@
+// Copyright 2008-present Facebook. All Rights Reserved.
+
+#ifndef STORAGE_LEVELDB_DB_LOG_FILE_H_
+#define STORAGE_LEVELDB_DB_LOG_FILE_H_
+
+namespace leveldb {
+
+enum  WalFileType {
+  kArchivedLogFile = 0,
+  kAliveLogFile = 1
+} ;
+
+class LogFile {
+
+ public:
+  uint64_t logNumber;
+  WalFileType type;
+
+  LogFile(uint64_t logNum,WalFileType logType) :
+    logNumber(logNum),
+    type(logType) {}
+
+  LogFile(const LogFile& that) {
+   logNumber = that.logNumber;
+   type = that.type;
+  }
+
+  bool operator < (const LogFile& that) const {
+    return logNumber < that.logNumber;
+  }
+
+  std::string ToString() const {
+    char response[100];
+    const char* typeOfLog;
+    if (type == kAliveLogFile) {
+      typeOfLog = "Alive Log";
+    } else {
+      typeOfLog = "Archived Log";
+    }
+    sprintf(response,
+            "LogNumber  : %ld LogType : %s",
+            logNumber,
+            typeOfLog);
+    return std::string(response);
+  }
+};
+}  //  namespace leveldb
+#endif  // STORAGE_LEVELDB_DB_LOG_FILE_H_
@@ -8,7 +8,7 @@
 #ifndef STORAGE_LEVELDB_DB_LOG_FORMAT_H_
 #define STORAGE_LEVELDB_DB_LOG_FORMAT_H_

-namespace rocksdb {
+namespace leveldb {
 namespace log {

 enum RecordType {
@@ -24,12 +24,12 @@ enum RecordType {
 };
 static const int kMaxRecordType = kLastType;

-static const unsigned int kBlockSize = 32768;
+static const int kBlockSize = 32768;

 // Header is checksum (4 bytes), type (1 byte), length (2 bytes).
 static const int kHeaderSize = 4 + 1 + 2;

 }  // namespace log
-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_LOG_FORMAT_H_
@@ -5,11 +5,11 @@
 #include "db/log_reader.h"

 #include <stdio.h>
-#include "rocksdb/env.h"
+#include "leveldb/env.h"
 #include "util/coding.h"
 #include "util/crc32c.h"

-namespace rocksdb {
+namespace leveldb {
 namespace log {

 Reader::Reporter::~Reporter() {
@@ -256,4 +256,4 @@ unsigned int Reader::ReadPhysicalRecord(Slice* result) {
 }

 }  // namespace log
-}  // namespace rocksdb
+}  // namespace leveldb
@@ -9,10 +9,10 @@
 #include <stdint.h>

 #include "db/log_format.h"
-#include "rocksdb/slice.h"
-#include "rocksdb/status.h"
+#include "leveldb/slice.h"
+#include "leveldb/status.h"

-namespace rocksdb {
+namespace leveldb {

 class SequentialFile;
 using std::unique_ptr;
@@ -59,17 +59,6 @@ class Reader {
  // Undefined before the first call to ReadRecord.
  uint64_t LastRecordOffset();

-  // returns true if the reader has encountered an eof condition.
-  bool IsEOF() {
-    return eof_;
-  }
-
-  // when we know more data has been written to the file. we can use this
-  // function to force the reader to look again in the file.
-  void UnmarkEOF() {
-    eof_ = false;
-  }
-
  SequentialFile* file() { return file_.get(); }

 private:
@@ -118,6 +107,6 @@ class Reader {
 };

 }  // namespace log
-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_LOG_READER_H_
@@ -4,13 +4,13 @@

 #include "db/log_reader.h"
 #include "db/log_writer.h"
-#include "rocksdb/env.h"
+#include "leveldb/env.h"
 #include "util/coding.h"
 #include "util/crc32c.h"
 #include "util/random.h"
 #include "util/testharness.h"

-namespace rocksdb {
+namespace leveldb {
 namespace log {

 // Construct a string of the specified length made out of the supplied
@@ -450,13 +450,13 @@ TEST(LogTest, ErrorJoinsRecords) {
  Write("correct");

  // Wipe the middle block
-  for (unsigned int offset = kBlockSize; offset < 2*kBlockSize; offset++) {
+  for (int offset = kBlockSize; offset < 2*kBlockSize; offset++) {
    SetByte(offset, 'x');
  }

  ASSERT_EQ("correct", Read());
  ASSERT_EQ("EOF", Read());
-  const unsigned int dropped = DroppedBytes();
+  const int dropped = DroppedBytes();
  ASSERT_LE(dropped, 2*kBlockSize + 100);
  ASSERT_GE(dropped, 2*kBlockSize);
 }
@@ -516,8 +516,8 @@ TEST(LogTest, ReadPastEnd) {
 }

 }  // namespace log
-}  // namespace rocksdb
+}  // namespace leveldb

 int main(int argc, char** argv) {
-  return rocksdb::test::RunAllTests();
+  return leveldb::test::RunAllTests();
 }
@@ -5,11 +5,11 @@
 #include "db/log_writer.h"

 #include <stdint.h>
-#include "rocksdb/env.h"
+#include "leveldb/env.h"
 #include "util/coding.h"
 #include "util/crc32c.h"

-namespace rocksdb {
+namespace leveldb {
 namespace log {

 Writer::Writer(unique_ptr<WritableFile>&& dest)
@@ -100,4 +100,4 @@ Status Writer::EmitPhysicalRecord(RecordType t, const char* ptr, size_t n) {
 }

 }  // namespace log
-}  // namespace rocksdb
+}  // namespace leveldb
@@ -8,10 +8,10 @@
 #include <memory>
 #include <stdint.h>
 #include "db/log_format.h"
-#include "rocksdb/slice.h"
-#include "rocksdb/status.h"
+#include "leveldb/slice.h"
+#include "leveldb/status.h"

-namespace rocksdb {
+namespace leveldb {

 class WritableFile;

@@ -49,6 +49,6 @@ class Writer {
 };

 }  // namespace log
-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_LOG_WRITER_H_
@@ -3,43 +3,37 @@
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

 #include "db/memtable.h"
-
-#include <memory>
-
 #include "db/dbformat.h"
-#include "rocksdb/comparator.h"
-#include "rocksdb/env.h"
-#include "rocksdb/iterator.h"
-#include "rocksdb/merge_operator.h"
+#include "leveldb/comparator.h"
+#include "leveldb/env.h"
+#include "leveldb/iterator.h"
 #include "util/coding.h"
-#include "util/murmurhash.h"

-namespace rocksdb {
+namespace leveldb {

-MemTable::MemTable(const InternalKeyComparator& cmp,
-                   std::shared_ptr<MemTableRepFactory> table_factory,
-                   int numlevel,
-                   const Options& options)
+static Slice GetLengthPrefixedSlice(const char* data) {
+  uint32_t len;
+  const char* p = data;
+  p = GetVarint32Ptr(p, p + 5, &len);  // +5: we assume "p" is not corrupted
+  return Slice(p, len);
+}
+
+MemTable::MemTable(const InternalKeyComparator& cmp, int numlevel)
    : comparator_(cmp),
      refs_(0),
-      arena_impl_(options.arena_block_size),
-      table_(table_factory->CreateMemTableRep(comparator_, &arena_impl_)),
+      table_(comparator_, &arena_),
      flush_in_progress_(false),
      flush_completed_(false),
      file_number_(0),
      edit_(numlevel),
-      first_seqno_(0),
-      mem_next_logfile_number_(0),
-      mem_logfile_number_(0) { }
+      first_seqno_(0) {
+}

 MemTable::~MemTable() {
  assert(refs_ == 0);
 }

-size_t MemTable::ApproximateMemoryUsage() {
-  return arena_impl_.ApproximateMemoryUsage() +
-    table_->ApproximateMemoryUsage();
-}
+size_t MemTable::ApproximateMemoryUsage() { return arena_.MemoryUsage(); }

 int MemTable::KeyComparator::operator()(const char* aptr, const char* bptr)
    const {
@@ -49,11 +43,6 @@ int MemTable::KeyComparator::operator()(const char* aptr, const char* bptr)
  return comparator.Compare(a, b);
 }

-Slice MemTableRep::UserKey(const char* key) const {
-  Slice slice = GetLengthPrefixedSlice(key);
-  return Slice(slice.data(), slice.size() - 8);
-}
-
 // Encode a suitable internal key target for "target" and return it.
 // Uses *scratch as scratch space, and the returned pointer will point
 // into this scratch space.
@@ -66,30 +55,24 @@ static const char* EncodeKey(std::string* scratch, const Slice& target) {

 class MemTableIterator: public Iterator {
 public:
-  explicit MemTableIterator(MemTableRep* table)
-    : iter_(table->GetIterator()) { }
+  explicit MemTableIterator(MemTable::Table* table) : iter_(table) { }

-  MemTableIterator(MemTableRep* table, const Slice* prefix)
-    : iter_(table->GetPrefixIterator(*prefix)) { }
-
-  virtual bool Valid() const { return iter_->Valid(); }
-  virtual void Seek(const Slice& k) { iter_->Seek(EncodeKey(&tmp_, k)); }
-  virtual void SeekToFirst() { iter_->SeekToFirst(); }
-  virtual void SeekToLast() { iter_->SeekToLast(); }
-  virtual void Next() { iter_->Next(); }
-  virtual void Prev() { iter_->Prev(); }
-  virtual Slice key() const {
-    return GetLengthPrefixedSlice(iter_->key());
-  }
+  virtual bool Valid() const { return iter_.Valid(); }
+  virtual void Seek(const Slice& k) { iter_.Seek(EncodeKey(&tmp_, k)); }
+  virtual void SeekToFirst() { iter_.SeekToFirst(); }
+  virtual void SeekToLast() { iter_.SeekToLast(); }
+  virtual void Next() { iter_.Next(); }
+  virtual void Prev() { iter_.Prev(); }
+  virtual Slice key() const { return GetLengthPrefixedSlice(iter_.key()); }
  virtual Slice value() const {
-    Slice key_slice = GetLengthPrefixedSlice(iter_->key());
+    Slice key_slice = GetLengthPrefixedSlice(iter_.key());
    return GetLengthPrefixedSlice(key_slice.data() + key_slice.size());
  }

  virtual Status status() const { return Status::OK(); }

 private:
-  std::shared_ptr<MemTableRep::Iterator> iter_;
+  MemTable::Table::Iterator iter_;
  std::string tmp_;       // For passing to EncodeKey

  // No copying allowed
@@ -97,12 +80,8 @@ class MemTableIterator: public Iterator {
  void operator=(const MemTableIterator&);
 };

-Iterator* MemTable::NewIterator(const Slice* prefix) {
-  if (prefix) {
-    return new MemTableIterator(table_.get(), prefix);
-  } else {
-    return new MemTableIterator(table_.get());
-  }
+Iterator* MemTable::NewIterator() {
+  return new MemTableIterator(&table_);
 }

 void MemTable::Add(SequenceNumber s, ValueType type,
@@ -119,7 +98,7 @@ void MemTable::Add(SequenceNumber s, ValueType type,
  const size_t encoded_len =
      VarintLength(internal_key_size) + internal_key_size +
      VarintLength(val_size) + val_size;
-  char* buf = arena_impl_.Allocate(encoded_len);
+  char* buf = arena_.Allocate(encoded_len);
  char* p = EncodeVarint32(buf, internal_key_size);
  memcpy(p, key.data(), key_size);
  p += key_size;
@@ -128,7 +107,7 @@ void MemTable::Add(SequenceNumber s, ValueType type,
  p = EncodeVarint32(p, val_size);
  memcpy(p, value.data(), val_size);
  assert((p + val_size) - buf == (unsigned)encoded_len);
-  table_->Insert(buf);
+  table_.Insert(buf);

  // The first sequence number inserted into the memtable
  assert(first_seqno_ == 0 || s > first_seqno_);
@@ -137,22 +116,11 @@ void MemTable::Add(SequenceNumber s, ValueType type,
  }
 }

-bool MemTable::Get(const LookupKey& key, std::string* value, Status* s,
-                   std::deque<std::string>* operands, const Options& options) {
+bool MemTable::Get(const LookupKey& key, std::string* value, Status* s) {
  Slice memkey = key.memtable_key();
-  std::shared_ptr<MemTableRep::Iterator> iter(
-    table_->GetIterator(key.user_key()));
-  iter->Seek(memkey.data());
-
-  // It is the caller's responsibility to allocate/delete operands list
-  assert(operands != nullptr);
-
-  bool merge_in_progress = s->IsMergeInProgress();
-  auto merge_operator = options.merge_operator.get();
-  auto logger = options.info_log;
-  std::string merge_result;
-
-  for (; iter->Valid(); iter->Next()) {
+  Table::Iterator iter(&table_);
+  iter.Seek(memkey.data());
+  if (iter.Valid()) {
    // entry format is:
    //    klength  varint32
    //    userkey  char[klength-8]
@@ -162,7 +130,7 @@ bool MemTable::Get(const LookupKey& key, std::string* value, Status* s,
    // Check that it belongs to same user key.  We do not check the
    // sequence number since the Seek() call above should have skipped
    // all entries with overly large sequence numbers.
-    const char* entry = iter->key();
+    const char* entry = iter.key();
    uint32_t key_length;
    const char* key_ptr = GetVarint32Ptr(entry, entry+5, &key_length);
    if (comparator_.comparator.user_comparator()->Compare(
@@ -173,69 +141,16 @@ bool MemTable::Get(const LookupKey& key, std::string* value, Status* s,
      switch (static_cast<ValueType>(tag & 0xff)) {
        case kTypeValue: {
          Slice v = GetLengthPrefixedSlice(key_ptr + key_length);
-          *s = Status::OK();
-          if (merge_in_progress) {
-            assert(merge_operator);
-            if (!merge_operator->FullMerge(key.user_key(), &v, *operands,
-                                           value, logger.get())) {
-              RecordTick(options.statistics, NUMBER_MERGE_FAILURES);
-              *s = Status::Corruption("Error: Could not perform merge.");
-            }
-          } else {
-            value->assign(v.data(), v.size());
-          }
+          value->assign(v.data(), v.size());
          return true;
        }
-        case kTypeDeletion: {
-          if (merge_in_progress) {
-            assert(merge_operator);
-            *s = Status::OK();
-            if (!merge_operator->FullMerge(key.user_key(), nullptr, *operands,
-                                           value, logger.get())) {
-              RecordTick(options.statistics, NUMBER_MERGE_FAILURES);
-              *s = Status::Corruption("Error: Could not perform merge.");
-            }
-          } else {
-            *s = Status::NotFound(Slice());
-          }
+        case kTypeDeletion:
+          *s = Status::NotFound(Slice());
          return true;
-        }
-        case kTypeMerge: {
-          Slice v = GetLengthPrefixedSlice(key_ptr + key_length);
-          merge_in_progress = true;
-          operands->push_front(v.ToString());
-          while(operands->size() >= 2) {
-            // Attempt to associative merge. (Returns true if successful)
-            if (merge_operator->PartialMerge(key.user_key(),
-                                             Slice((*operands)[0]),
-                                             Slice((*operands)[1]),
-                                             &merge_result,
-                                             logger.get())) {
-              operands->pop_front();
-              swap(operands->front(), merge_result);
-            } else {
-              // Stack them because user can't associative merge
-              break;
-            }
-          }
-          break;
-        }
-        case kTypeLogData:
-          assert(false);
-          break;
      }
-    } else {
-      // exit loop if user key does not match
-      break;
    }
  }
-
-  // No change to value, since we have not yet found a Put/Delete
-
-  if (merge_in_progress) {
-    *s = Status::MergeInProgress("");
-  }
  return false;
 }

-}  // namespace rocksdb
+}  // namespace leveldb
@@ -6,35 +6,24 @@
 #define STORAGE_LEVELDB_DB_MEMTABLE_H_

 #include <string>
-#include <memory>
-#include <deque>
+#include "leveldb/db.h"
 #include "db/dbformat.h"
 #include "db/skiplist.h"
 #include "db/version_set.h"
-#include "rocksdb/db.h"
-#include "rocksdb/memtablerep.h"
-#include "util/arena_impl.h"
+#include "util/arena.h"

-namespace rocksdb {
+namespace leveldb {

+class InternalKeyComparator;
 class Mutex;
 class MemTableIterator;

 class MemTable {
 public:
-  struct KeyComparator : public MemTableRep::KeyComparator {
-    const InternalKeyComparator comparator;
-    explicit KeyComparator(const InternalKeyComparator& c) : comparator(c) { }
-    virtual int operator()(const char* a, const char* b) const;
-  };
-
  // MemTables are reference counted.  The initial reference count
  // is zero and the caller must call Ref() at least once.
-  explicit MemTable(
-    const InternalKeyComparator& comparator,
-    std::shared_ptr<MemTableRepFactory> table_factory,
-    int numlevel = 7,
-    const Options& options = Options());
+  explicit MemTable(const InternalKeyComparator& comparator,
+                    int numlevel = 7);

  // Increase reference count.
  void Ref() { ++refs_; }
@@ -61,11 +50,7 @@ class MemTable {
  // while the returned iterator is live.  The keys returned by this
  // iterator are internal keys encoded by AppendInternalKey in the
  // db/dbformat.{h,cc} module.
-  //
-  // If a prefix is supplied, it is passed to the underlying MemTableRep as a
-  // hint that the iterator only need to support access to keys with that
-  // prefix.
-  Iterator* NewIterator(const Slice* prefix = nullptr);
+  Iterator* NewIterator();

  // Add an entry into memtable that maps key to value at the
  // specified sequence number and with the specified type.
@@ -77,13 +62,8 @@ class MemTable {
  // If memtable contains a value for key, store it in *value and return true.
  // If memtable contains a deletion for key, store a NotFound() error
  // in *status and return true.
-  // If memtable contains Merge operation as the most recent entry for a key,
-  //   and the merge process does not stop (not reaching a value or delete),
-  //   prepend the current merge operand to *operands.
-  //   store MergeInProgress in s, and return false.
  // Else, return false.
-  bool Get(const LookupKey& key, std::string* value, Status* s,
-           std::deque<std::string>* operands, const Options& options);
+  bool Get(const LookupKey& key, std::string* value, Status* s);

  // Returns the edits area that is needed for flushing the memtable
  VersionEdit* GetEdits() { return &edit_; }
@@ -92,35 +72,24 @@ class MemTable {
  // into the memtable
  SequenceNumber GetFirstSequenceNumber() { return first_seqno_; }

-  // Returns the next active logfile number when this memtable is about to
-  // be flushed to storage
-  uint64_t GetNextLogNumber() { return mem_next_logfile_number_; }
-
-  // Sets the next active logfile number when this memtable is about to
-  // be flushed to storage
-  void SetNextLogNumber(uint64_t num) { mem_next_logfile_number_ = num; }
-
-  // Returns the logfile number that can be safely deleted when this
-  // memstore is flushed to storage
-  uint64_t GetLogNumber() { return mem_logfile_number_; }
-
-  // Sets the logfile number that can be safely deleted when this
-  // memstore is flushed to storage
-  void SetLogNumber(uint64_t num) { mem_logfile_number_ = num; }
-
-  // Notify the underlying storage that no more items will be added
-  void MarkImmutable() { table_->MarkReadOnly(); }
-
 private:
  ~MemTable();  // Private since only Unref() should be used to delete it
+
+  struct KeyComparator {
+    const InternalKeyComparator comparator;
+    explicit KeyComparator(const InternalKeyComparator& c) : comparator(c) { }
+    int operator()(const char* a, const char* b) const;
+  };
  friend class MemTableIterator;
  friend class MemTableBackwardIterator;
  friend class MemTableList;

+  typedef SkipList<const char*, KeyComparator> Table;
+
  KeyComparator comparator_;
  int refs_;
-  ArenaImpl arena_impl_;
-  shared_ptr<MemTableRep> table_;
+  Arena arena_;
+  Table table_;

  // These are used to manage memtable flushes to storage
  bool flush_in_progress_; // started the flush
@@ -134,18 +103,11 @@ class MemTable {
  // The sequence number of the kv that was inserted first
  SequenceNumber first_seqno_;

-  // The log files earlier than this number can be deleted.
-  uint64_t mem_next_logfile_number_;
-
-  // The log file that backs this memtable (to be deleted when
-  // memtable flush is done)
-  uint64_t mem_logfile_number_;
-
  // No copying allowed
  MemTable(const MemTable&);
  void operator=(const MemTable&);
 };

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_MEMTABLE_H_
@@ -4,13 +4,13 @@
 #include "db/memtablelist.h"

 #include <string>
-#include "rocksdb/db.h"
+#include "leveldb/db.h"
 #include "db/memtable.h"
-#include "rocksdb/env.h"
-#include "rocksdb/iterator.h"
+#include "leveldb/env.h"
+#include "leveldb/iterator.h"
 #include "util/coding.h"

-namespace rocksdb {
+namespace leveldb {

 class InternalKeyComparator;
 class Mutex;
@@ -21,15 +21,17 @@ using std::list;

 // Increase reference count on all underling memtables
 void MemTableList::RefAll() {
-  for (auto &memtable : memlist_) {
-    memtable->Ref();
+  for (list<MemTable*>::iterator it = memlist_.begin();
+       it != memlist_.end() ; ++it) {
+    (*it)->Ref();
  }
 }

 // Drop reference count on all underling memtables
 void MemTableList::UnrefAll() {
-  for (auto &memtable : memlist_) {
-    memtable->Unref();
+  for (list<MemTable*>::iterator it = memlist_.begin();
+       it != memlist_.end() ; ++it) {
+    (*it)->Unref();
  }
 }

@@ -41,18 +43,19 @@ int MemTableList::size() {

 // Returns true if there is at least one memtable on which flush has
 // not yet started.
-bool MemTableList::IsFlushPending(int min_write_buffer_number_to_merge) {
-  if ((flush_requested_ && num_flush_not_started_ >= 1) ||
-      (num_flush_not_started_ >= min_write_buffer_number_to_merge)) {
+bool MemTableList::IsFlushPending() {
+  if (num_flush_not_started_ > 0) {
    assert(imm_flush_needed.NoBarrier_Load() != nullptr);
    return true;
  }
  return false;
 }

-// Returns the memtables that need to be flushed.
-void MemTableList::PickMemtablesToFlush(std::vector<MemTable*>* ret) {
-  for (auto it = memlist_.rbegin(); it != memlist_.rend(); it++) {
+// Returns the earliest memtable that needs to be flushed.
+// Returns null, if no such memtable exist.
+MemTable* MemTableList::PickMemtableToFlush() {
+  for (list<MemTable*>::reverse_iterator it = memlist_.rbegin();
+       it != memlist_.rend(); it++) {
    MemTable* m = *it;
    if (!m->flush_in_progress_) {
      assert(!m->flush_completed_);
@@ -61,49 +64,37 @@ void MemTableList::PickMemtablesToFlush(std::vector<MemTable*>* ret) {
        imm_flush_needed.Release_Store(nullptr);
      }
      m->flush_in_progress_ = true; // flushing will start very soon
-      ret->push_back(m);
+      return m;
    }
  }
-  flush_requested_ = false; // start-flush request is complete
+  return nullptr;
 }

 // Record a successful flush in the manifest file
-Status MemTableList::InstallMemtableFlushResults(
-                      const std::vector<MemTable*> &mems,
+Status MemTableList::InstallMemtableFlushResults(MemTable* m,
                      VersionSet* vset, Status flushStatus,
                      port::Mutex* mu, Logger* info_log,
                      uint64_t file_number,
                      std::set<uint64_t>& pending_outputs) {
  mu->AssertHeld();
+  assert(m->flush_in_progress_);
+  assert(m->file_number_ == 0);

  // If the flush was not successful, then just reset state.
  // Maybe a suceeding attempt to flush will be successful.
  if (!flushStatus.ok()) {
-    for (MemTable* m : mems) {
-      assert(m->flush_in_progress_);
-      assert(m->file_number_ == 0);
-
-      m->flush_in_progress_ = false;
-      m->flush_completed_ = false;
-      m->edit_.Clear();
-      num_flush_not_started_++;
-      imm_flush_needed.Release_Store((void *)1);
-      pending_outputs.erase(file_number);
-    }
+    m->flush_in_progress_ = false;
+    m->flush_completed_ = false;
+    m->edit_.Clear();
+    num_flush_not_started_++;
+    imm_flush_needed.Release_Store((void *)1);
+    pending_outputs.erase(file_number);
    return flushStatus;
  }

  // flush was sucessful
-  bool first = true;
-  for (MemTable* m : mems) {
-
-    // All the edits are associated with the first memtable of this batch.
-    assert(first || m->GetEdits()->NumEntries() == 0);
-    first = false;
-
-    m->flush_completed_ = true;
-    m->file_number_ = file_number;
-  }
+  m->flush_completed_ = true;
+  m->file_number_ = file_number;

  // if some other thread is already commiting, then return
  Status s;
@@ -115,15 +106,12 @@ Status MemTableList::InstallMemtableFlushResults(
  commit_in_progress_ = true;

  // scan all memtables from the earliest, and commit those
-  // (in that order) that have finished flushing. Memetables
-  // are always committed in the order that they were created.
-  while (!memlist_.empty() && s.ok()) {
-    MemTable* m = memlist_.back(); // get the last element
+  // (in that order) that have finished flushing.
+  while (!memlist_.empty()) {
+    m = memlist_.back(); // get the last element
    if (!m->flush_completed_) {
      break;
    }
-    first = true;
-
    Log(info_log,
        "Level-0 commit table #%llu: started",
        (unsigned long long)m->file_number_);
@@ -131,39 +119,33 @@ Status MemTableList::InstallMemtableFlushResults(
    // this can release and reacquire the mutex.
    s = vset->LogAndApply(&m->edit_, mu);

-    // All the later memtables that have the same filenum
-    // are part of the same batch. They can be committed now.
-    do {
-      if (s.ok()) { // commit new state
-        Log(info_log, "Level-0 commit table #%llu: done %s",
-                       (unsigned long long)m->file_number_,
-                       first ? "": "bulk");
-        memlist_.remove(m);
-        assert(m->file_number_ > 0);
+    if (s.ok()) { // commit new state
+      Log(info_log, "Level-0 commit table #%llu: done",
+                     (unsigned long long)m->file_number_);
+      memlist_.remove(m);
+      assert(m->file_number_ > 0);

-        // pending_outputs can be cleared only after the newly created file
-        // has been written to a committed version so that other concurrently
-        // executing compaction threads do not mistakenly assume that this
-        // file is not live.
-        pending_outputs.erase(m->file_number_);
-        m->Unref();
-        size_--;
-      } else {
-        //commit failed. setup state so that we can flush again.
-        Log(info_log, "Level-0 commit table #%llu: failed",
-                       (unsigned long long)m->file_number_);
-        m->flush_completed_ = false;
-        m->flush_in_progress_ = false;
-        m->edit_.Clear();
-        num_flush_not_started_++;
-        pending_outputs.erase(m->file_number_);
-        m->file_number_ = 0;
-        imm_flush_needed.Release_Store((void *)1);
-        s = Status::IOError("Unable to commit flushed memtable");
-      }
-      first = false;
-    } while (!memlist_.empty() && (m = memlist_.back()) &&
-             m->file_number_ == file_number);
+      // pending_outputs can be cleared only after the newly created file
+      // has been written to a committed version so that other concurrently
+      // executing compaction threads do not mistakenly assume that this
+      // file is not live.
+      pending_outputs.erase(m->file_number_);
+      m->Unref();
+      size_--;
+    } else {
+      //commit failed. setup state so that we can flush again.
+      Log(info_log, "Level-0 commit table #%llu: failed",
+                     (unsigned long long)m->file_number_);
+      m->flush_completed_ = false;
+      m->flush_in_progress_ = false;
+      m->edit_.Clear();
+      num_flush_not_started_++;
+      pending_outputs.erase(m->file_number_);
+      m->file_number_ = 0;
+      imm_flush_needed.Release_Store((void *)1);
+      s = Status::IOError("Unable to commit flushed memtable");
+      break;
+    }
  }
  commit_in_progress_ = false;
  return s;
@@ -174,7 +156,6 @@ void MemTableList::Add(MemTable* m) {
  assert(size_ >= num_flush_not_started_);
  size_++;
  memlist_.push_front(m);
-  m->MarkImmutable();
  num_flush_not_started_++;
  if (num_flush_not_started_ == 1) {
    imm_flush_needed.Release_Store((void *)1);
@@ -184,20 +165,19 @@ void MemTableList::Add(MemTable* m) {
 // Returns an estimate of the number of bytes of data in use.
 size_t MemTableList::ApproximateMemoryUsage() {
  size_t size = 0;
-  for (auto &memtable : memlist_) {
-    size += memtable->ApproximateMemoryUsage();
+  for (list<MemTable*>::iterator it = memlist_.begin();
+       it != memlist_.end(); ++it) {
+    size += (*it)->ApproximateMemoryUsage();
  }
  return size;
 }

 // Search all the memtables starting from the most recent one.
 // Return the most recent value found, if any.
-// Operands stores the list of merge operations to apply, so far.
-bool MemTableList::Get(const LookupKey& key, std::string* value, Status* s,
-                       std::deque<std::string>* operands,
-                       const Options& options) {
-  for (auto &memtable : memlist_) {
-    if (memtable->Get(key, value, s, operands, options)) {
+bool MemTableList::Get(const LookupKey& key, std::string* value, Status* s) {
+  for (list<MemTable*>::iterator it = memlist_.begin();
+       it != memlist_.end(); ++it) {
+    if ((*it)->Get(key, value, s)) {
      return true;
    }
  }
@@ -205,9 +185,10 @@ bool MemTableList::Get(const LookupKey& key, std::string* value, Status* s,
 }

 void MemTableList::GetMemTables(std::vector<MemTable*>* output) {
-  for (auto &memtable : memlist_) {
-    output->push_back(memtable);
+  for (list<MemTable*>::iterator it = memlist_.begin();
+       it != memlist_.end(); ++it) {
+    output->push_back(*it);
  }
 }

-}  // namespace rocksdb
+}  // namespace leveldb
@@ -5,20 +5,20 @@

 #include <string>
 #include <list>
-#include <deque>
-#include "rocksdb/db.h"
+#include "leveldb/db.h"
 #include "db/dbformat.h"
 #include "db/skiplist.h"
+#include "util/arena.h"
 #include "memtable.h"

-namespace rocksdb {
+namespace leveldb {

 class InternalKeyComparator;
 class Mutex;
 class MemTableListIterator;

 //
-// This class stores references to all the immutable memtables.
+// This class stores refeernces to all the immutable memtables.
 // The memtables are flushed to L0 as soon as possible and in
 // any order. If there are more than one immutable memtable, their
 // flushes can occur concurrently.  However, they are 'committed'
@@ -29,8 +29,7 @@ class MemTableList {
 public:
  // A list of memtables.
  MemTableList() : size_(0), num_flush_not_started_(0),
-    commit_in_progress_(false),
-    flush_requested_(false) {
+    commit_in_progress_(false) {
    imm_flush_needed.Release_Store(nullptr);
  }
  ~MemTableList() {};
@@ -50,13 +49,14 @@ class MemTableList {

  // Returns true if there is at least one memtable on which flush has
  // not yet started.
-  bool IsFlushPending(int min_write_buffer_number_to_merge);
+  bool IsFlushPending();

-  // Returns the earliest memtables that needs to be flushed.
-  void PickMemtablesToFlush(std::vector<MemTable*>* mems);
+  // Returns the earliest memtable that needs to be flushed.
+  // Returns null, if no such memtable exist.
+  MemTable* PickMemtableToFlush();

  // Commit a successful flush in the manifest file
-  Status InstallMemtableFlushResults(const std::vector<MemTable*> &m,
+  Status InstallMemtableFlushResults(MemTable* m,
                      VersionSet* vset, Status flushStatus,
                      port::Mutex* mu, Logger* info_log,
                      uint64_t file_number,
@@ -71,15 +71,11 @@ class MemTableList {

  // Search all the memtables starting from the most recent one.
  // Return the most recent value found, if any.
-  bool Get(const LookupKey& key, std::string* value, Status* s,
-           std::deque<std::string>* operands, const Options& options);
+  bool Get(const LookupKey& key, std::string* value, Status* s);

  // Returns the list of underlying memtables.
  void GetMemTables(std::vector<MemTable*>* list);

-  // Request a flush of all existing memtables to storage
-  void FlushRequested() { flush_requested_ = true; }
-
  // Copying allowed
  // MemTableList(const MemTableList&);
  // void operator=(const MemTableList&);
@@ -94,11 +90,8 @@ class MemTableList {
  // committing in progress
  bool commit_in_progress_;

-  // Requested a flush of all memtables to storage
-  bool flush_requested_;
-
 };

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_MEMTABLELIST_H_
@@ -1,192 +0,0 @@
-#include "merge_helper.h"
-#include "db/dbformat.h"
-#include "rocksdb/comparator.h"
-#include "rocksdb/db.h"
-#include "rocksdb/merge_operator.h"
-#include <string>
-#include <stdio.h>
-
-namespace rocksdb {
-
-// PRE:  iter points to the first merge type entry
-// POST: iter points to the first entry beyond the merge process (or the end)
-//       keys_, operands_ are updated to reflect the merge result.
-//       keys_ stores the list of keys encountered while merging.
-//       operands_ stores the list of merge operands encountered while merging.
-//       keys_[i] corresponds to operands_[i] for each i.
-void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
-                             bool at_bottom, shared_ptr<Statistics> stats) {
-  // Get a copy of the internal key, before it's invalidated by iter->Next()
-  // Also maintain the list of merge operands seen.
-  keys_.clear();
-  operands_.clear();
-  keys_.push_front(iter->key().ToString());
-  operands_.push_front(iter->value().ToString());
-
-  success_ = false;   // Will become true if we hit Put/Delete or bottom
-
-  // We need to parse the internal key again as the parsed key is
-  // backed by the internal key!
-  // Assume no internal key corruption as it has been successfully parsed
-  // by the caller.
-  // Invariant: keys_.back() will not change. Hence, orig_ikey is always valid.
-  ParsedInternalKey orig_ikey;
-  ParseInternalKey(keys_.back(), &orig_ikey);
-
-  bool hit_the_next_user_key = false;
-  ParsedInternalKey ikey;
-  std::string merge_result;  // Temporary value for merge results
-  for (iter->Next(); iter->Valid(); iter->Next()) {
-    assert(operands_.size() >= 1);        // Should be invariants!
-    assert(keys_.size() == operands_.size());
-
-    if (!ParseInternalKey(iter->key(), &ikey)) {
-      // stop at corrupted key
-      if (assert_valid_internal_key_) {
-        assert(!"corrupted internal key is not expected");
-      }
-      break;
-    }
-
-    if (user_comparator_->Compare(ikey.user_key, orig_ikey.user_key) != 0) {
-      // hit a different user key, stop right here
-      hit_the_next_user_key = true;
-      break;
-    }
-
-    if (stop_before && ikey.sequence <= stop_before) {
-      // hit an entry that's visible by the previous snapshot, can't touch that
-      break;
-    }
-
-    // At this point we are guaranteed that we need to process this key.
-
-    if (kTypeDeletion == ikey.type) {
-      // hit a delete
-      //   => merge nullptr with operands_
-      //   => store result in operands_.back() (and update keys_.back())
-      //   => change the entry type to kTypeValue for keys_.back()
-      // We are done! Return a success if the merge passes.
-      success_ = user_merge_operator_->FullMerge(ikey.user_key, nullptr,
-                                                 operands_, &merge_result,
-                                                 logger_);
-
-      // We store the result in keys_.back() and operands_.back()
-      // if nothing went wrong (i.e.: no operand corruption on disk)
-      if (success_) {
-        std::string& key = keys_.back();  // The original key encountered
-        orig_ikey.type = kTypeValue;
-        UpdateInternalKey(&key[0], key.size(),
-                          orig_ikey.sequence, orig_ikey.type);
-        swap(operands_.back(), merge_result);
-      } else {
-        RecordTick(stats, NUMBER_MERGE_FAILURES);
-      }
-
-      // move iter to the next entry (before doing anything else)
-      iter->Next();
-      return;
-    }
-
-    if (kTypeValue == ikey.type) {
-      // hit a put
-      //   => merge the put value with operands_
-      //   => store result in operands_.back() (and update keys_.back())
-      //   => change the entry type to kTypeValue for keys_.back()
-      // We are done! Success!
-      const Slice value = iter->value();
-      success_ = user_merge_operator_->FullMerge(ikey.user_key, &value,
-                                                 operands_, &merge_result,
-                                                 logger_);
-
-      // We store the result in keys_.back() and operands_.back()
-      // if nothing went wrong (i.e.: no operand corruption on disk)
-      if (success_) {
-        std::string& key = keys_.back();  // The original key encountered
-        orig_ikey.type = kTypeValue;
-        UpdateInternalKey(&key[0], key.size(),
-                          orig_ikey.sequence, orig_ikey.type);
-        swap(operands_.back(), merge_result);
-      } else {
-        RecordTick(stats, NUMBER_MERGE_FAILURES);
-      }
-
-      // move iter to the next entry
-      iter->Next();
-      return;
-    }
-
-    if (kTypeMerge == ikey.type) {
-      // hit a merge
-      //   => merge the operand into the front of the operands_ list
-      //   => use the user's associative merge function to determine how.
-      //   => then continue because we haven't yet seen a Put/Delete.
-      assert(!operands_.empty()); // Should have at least one element in it
-
-      keys_.push_front(iter->key().ToString());
-      operands_.push_front(iter->value().ToString());
-      while (operands_.size() >= 2) {
-        // Returns false when the merge_operator can no longer process it
-        if (user_merge_operator_->PartialMerge(ikey.user_key,
-                                               Slice(operands_[0]),
-                                               Slice(operands_[1]),
-                                               &merge_result,
-                                               logger_)) {
-          // Merging of operands (associative merge) was successful.
-          // Replace these frontmost two operands with the merge result
-          keys_.pop_front();
-          operands_.pop_front();
-          swap(operands_.front(), merge_result);
-        } else {
-          // Merging of operands (associative merge) returned false.
-          // The user merge_operator does not know how to merge these operands.
-          // So we just stack them up until we find a Put/Delete or end of key.
-          break;
-        }
-      }
-      continue;
-    }
-  }
-
-  // We are sure we have seen this key's entire history if we are at the
-  // last level and exhausted all internal keys of this user key.
-  // NOTE: !iter->Valid() does not necessarily mean we hit the
-  // beginning of a user key, as versions of a user key might be
-  // split into multiple files (even files on the same level)
-  // and some files might not be included in the compaction/merge.
-  //
-  // There are also cases where we have seen the root of history of this
-  // key without being sure of it. Then, we simply miss the opportunity
-  // to combine the keys. Since VersionSet::SetupOtherInputs() always makes
-  // sure that all merge-operands on the same level get compacted together,
-  // this will simply lead to these merge operands moving to the next level.
-  //
-  // So, we only perform the following logic (to merge all operands together
-  // without a Put/Delete) if we are certain that we have seen the end of key.
-  bool surely_seen_the_beginning = hit_the_next_user_key && at_bottom;
-  if (surely_seen_the_beginning) {
-    // do a final merge with nullptr as the existing value and say
-    // bye to the merge type (it's now converted to a Put)
-    assert(kTypeMerge == orig_ikey.type);
-    assert(operands_.size() >= 1);
-    assert(operands_.size() == keys_.size());
-    success_ = user_merge_operator_->FullMerge(ikey.user_key, nullptr,
-                                               operands_, &merge_result,
-                                               logger_);
-
-    if (success_) {
-      std::string& key = keys_.back();  // The original key encountered
-      orig_ikey.type = kTypeValue;
-      UpdateInternalKey(&key[0], key.size(),
-                        orig_ikey.sequence, orig_ikey.type);
-
-      // The final value() is always stored in operands_.back()
-      swap(operands_.back(),merge_result);
-    } else {
-      RecordTick(stats, NUMBER_MERGE_FAILURES);
-      // Do nothing if not success_. Leave keys() and operands() as they are.
-    }
-  }
-}
-
-} // namespace rocksdb
@@ -1,98 +0,0 @@
-#ifndef MERGE_HELPER_H
-#define MERGE_HELPER_H
-
-#include "db/dbformat.h"
-#include "rocksdb/slice.h"
-#include "rocksdb/statistics.h"
-#include <string>
-#include <deque>
-
-namespace rocksdb {
-
-class Comparator;
-class Iterator;
-class Logger;
-class MergeOperator;
-
-class MergeHelper {
- public:
-  MergeHelper(const Comparator* user_comparator,
-              const MergeOperator* user_merge_operator,
-              Logger* logger,
-              bool assert_valid_internal_key)
-      : user_comparator_(user_comparator),
-        user_merge_operator_(user_merge_operator),
-        logger_(logger),
-        assert_valid_internal_key_(assert_valid_internal_key),
-        keys_(),
-        operands_(),
-        success_(false) {}
-
-  // Merge entries until we hit
-  //     - a corrupted key
-  //     - a Put/Delete,
-  //     - a different user key,
-  //     - a specific sequence number (snapshot boundary),
-  //  or - the end of iteration
-  // iter: (IN)  points to the first merge type entry
-  //       (OUT) points to the first entry not included in the merge process
-  // stop_before: (IN) a sequence number that merge should not cross.
-  //                   0 means no restriction
-  // at_bottom:   (IN) true if the iterator covers the bottem level, which means
-  //                   we could reach the start of the history of this user key.
-  void MergeUntil(Iterator* iter, SequenceNumber stop_before = 0,
-                  bool at_bottom = false, shared_ptr<Statistics> stats=nullptr);
-
-  // Query the merge result
-  // These are valid until the next MergeUntil call
-  // If the merging was successful:
-  //   - IsSuccess() will be true
-  //   - key() will have the latest sequence number of the merges.
-  //           The type will be Put or Merge. See IMPORTANT 1 note, below.
-  //   - value() will be the result of merging all the operands together
-  //   - The user should ignore keys() and values().
-  //
-  //   IMPORTANT 1: the key type could change after the MergeUntil call.
-  //        Put/Delete + Merge + ... + Merge => Put
-  //        Merge + ... + Merge => Merge
-  //
-  // If the merge operator is not associative, and if a Put/Delete is not found
-  // then the merging will be unsuccessful. In this case:
-  //   - IsSuccess() will be false
-  //   - keys() contains the list of internal keys seen in order of iteration.
-  //   - values() contains the list of values (merges) seen in the same order.
-  //              values() is parallel to keys() so that the first entry in
-  //              keys() is the key associated with the first entry in values()
-  //              and so on. These lists will be the same length.
-  //              All of these pairs will be merges over the same user key.
-  //              See IMPORTANT 2 note below.
-  //   - The user should ignore key() and value().
-  //
-  //   IMPORTANT 2: The entries were traversed in order from BACK to FRONT.
-  //                So keys().back() was the first key seen by iterator.
-  // TODO: Re-style this comment to be like the first one
-  bool IsSuccess() { return success_; }
-  Slice key() { assert(success_); return Slice(keys_.back()); }
-  Slice value() { assert(success_); return Slice(operands_.back()); }
-  const std::deque<std::string>& keys() { assert(!success_); return keys_; }
-  const std::deque<std::string>& values() {
-    assert(!success_); return operands_;
-  }
-
- private:
-  const Comparator* user_comparator_;
-  const MergeOperator* user_merge_operator_;
-  Logger* logger_;
-  Iterator* iter_; // in: the internal iterator, positioned at the first merge entry
-  bool assert_valid_internal_key_; // enforce no internal key corruption?
-
-  // the scratch area that holds the result of MergeUntil
-  // valid up to the next MergeUntil call
-  std::deque<std::string> keys_;    // Keeps track of the sequence of keys seen
-  std::deque<std::string> operands_;  // Parallel with keys_; stores the values
-  bool success_;
-};
-
-} // namespace rocksdb
-
-#endif
@@ -1,51 +0,0 @@
-/**
- * Back-end implementation details specific to the Merge Operator.
- *
- * @author Deon Nicholas (dnicholas@fb.com)
- * Copyright 2013 Facebook
- */
-
-#include "rocksdb/merge_operator.h"
-
-namespace rocksdb {
-
-// Given a "real" merge from the library, call the user's
-// associative merge function one-by-one on each of the operands.
-// NOTE: It is assumed that the client's merge-operator will handle any errors.
-bool AssociativeMergeOperator::FullMerge(
-    const Slice& key,
-    const Slice* existing_value,
-    const std::deque<std::string>& operand_list,
-    std::string* new_value,
-    Logger* logger) const {
-
-  // Simply loop through the operands
-  Slice temp_existing;
-  std::string temp_value;
-  for (const auto& operand : operand_list) {
-    Slice value(operand);
-    if (!Merge(key, existing_value, value, &temp_value, logger)) {
-      return false;
-    }
-    swap(temp_value, *new_value);
-    temp_existing = Slice(*new_value);
-    existing_value = &temp_existing;
-  }
-
-  // The result will be in *new_value. All merges succeeded.
-  return true;
-}
-
-// Call the user defined simple merge on the operands;
-// NOTE: It is assumed that the client's merge-operator will handle any errors.
-bool AssociativeMergeOperator::PartialMerge(
-    const Slice& key,
-    const Slice& left_operand,
-    const Slice& right_operand,
-    std::string* new_value,
-    Logger* logger) const {
-
-  return Merge(key, &left_operand, right_operand, new_value, logger);
-}
-
-} // namespace rocksdb
@@ -1,270 +0,0 @@
-#include <assert.h>
-#include <memory>
-#include <iostream>
-
-#include "rocksdb/cache.h"
-#include "rocksdb/comparator.h"
-#include "rocksdb/db.h"
-#include "rocksdb/env.h"
-#include "rocksdb/merge_operator.h"
-#include "db/dbformat.h"
-#include "db/db_impl.h"
-#include "utilities/merge_operators.h"
-#include "util/testharness.h"
-#include "utilities/utility_db.h"
-
-using namespace std;
-using namespace rocksdb;
-
-
-std::shared_ptr<DB> OpenDb(const string& dbname, const bool ttl = false) {
-  DB* db;
-  StackableDB* sdb;
-  Options options;
-  options.create_if_missing = true;
-  options.merge_operator = MergeOperators::CreateUInt64AddOperator();
-  Status s;
-  DestroyDB(dbname, Options());
-  if (ttl) {
-    cout << "Opening database with TTL\n";
-    s = UtilityDB::OpenTtlDB(options, dbname, &sdb);
-    db = sdb;
-  } else {
-    s = DB::Open(options, dbname, &db);
-  }
-  if (!s.ok()) {
-    cerr << s.ToString() << endl;
-    assert(false);
-  }
-  return std::shared_ptr<DB>(db);
-}
-
-// Imagine we are maintaining a set of uint64 counters.
-// Each counter has a distinct name. And we would like
-// to support four high level operations:
-// set, add, get and remove
-// This is a quick implementation without a Merge operation.
-class Counters {
-
- protected:
-  std::shared_ptr<DB> db_;
-
-  WriteOptions put_option_;
-  ReadOptions get_option_;
-  WriteOptions delete_option_;
-
-  uint64_t default_;
-
- public:
-  explicit Counters(std::shared_ptr<DB> db, uint64_t defaultCount = 0)
-      : db_(db),
-        put_option_(),
-        get_option_(),
-        delete_option_(),
-        default_(defaultCount) {
-    assert(db_);
-  }
-
-  virtual ~Counters() {}
-
-  // public interface of Counters.
-  // All four functions return false
-  // if the underlying level db operation failed.
-
-  // mapped to a levedb Put
-  bool set(const string& key, uint64_t value) {
-    // just treat the internal rep of int64 as the string
-    Slice slice((char *)&value, sizeof(value));
-    auto s = db_->Put(put_option_, key, slice);
-
-    if (s.ok()) {
-      return true;
-    } else {
-      cerr << s.ToString() << endl;
-      return false;
-    }
-  }
-
-  // mapped to a leveldb Delete
-  bool remove(const string& key) {
-    auto s = db_->Delete(delete_option_, key);
-
-    if (s.ok()) {
-      return true;
-    } else {
-      cerr << s.ToString() << std::endl;
-      return false;
-    }
-  }
-
-  // mapped to a leveldb Get
-  bool get(const string& key, uint64_t *value) {
-    string str;
-    auto s = db_->Get(get_option_, key, &str);
-
-    if (s.IsNotFound()) {
-      // return default value if not found;
-      *value = default_;
-      return true;
-    } else if (s.ok()) {
-      // deserialization
-      if (str.size() != sizeof(uint64_t)) {
-        cerr << "value corruption\n";
-        return false;
-      }
-      *value = DecodeFixed64(&str[0]);
-      return true;
-    } else {
-      cerr << s.ToString() << std::endl;
-      return false;
-    }
-  }
-
-  // 'add' is implemented as get -> modify -> set
-  // An alternative is a single merge operation, see MergeBasedCounters
-  virtual bool add(const string& key, uint64_t value) {
-    uint64_t base = default_;
-    return get(key, &base) && set(key, base + value);
-  }
-
-
-  // convenience functions for testing
-  void assert_set(const string& key, uint64_t value) {
-    assert(set(key, value));
-  }
-
-  void assert_remove(const string& key) {
-    assert(remove(key));
-  }
-
-  uint64_t assert_get(const string& key) {
-    uint64_t value = default_;
-    assert(get(key, &value));
-    return value;
-  }
-
-  void assert_add(const string& key, uint64_t value) {
-    assert(add(key, value));
-  }
-};
-
-// Implement 'add' directly with the new Merge operation
-class MergeBasedCounters : public Counters {
- private:
-  WriteOptions merge_option_; // for merge
-
- public:
-  explicit MergeBasedCounters(std::shared_ptr<DB> db, uint64_t defaultCount = 0)
-      : Counters(db, defaultCount),
-        merge_option_() {
-  }
-
-  // mapped to a leveldb Merge operation
-  virtual bool add(const string& key, uint64_t value) override {
-    char encoded[sizeof(uint64_t)];
-    EncodeFixed64(encoded, value);
-    Slice slice(encoded, sizeof(uint64_t));
-    auto s = db_->Merge(merge_option_, key, slice);
-
-    if (s.ok()) {
-      return true;
-    } else {
-      cerr << s.ToString() << endl;
-      return false;
-    }
-  }
-};
-
-void dumpDb(DB* db) {
-  auto it = unique_ptr<Iterator>(db->NewIterator(ReadOptions()));
-  for (it->SeekToFirst(); it->Valid(); it->Next()) {
-    uint64_t value = DecodeFixed64(it->value().data());
-    cout << it->key().ToString() << ": "  << value << endl;
-  }
-  assert(it->status().ok());  // Check for any errors found during the scan
-}
-
-void testCounters(Counters& counters, DB* db, bool test_compaction) {
-
-  FlushOptions o;
-  o.wait = true;
-
-  counters.assert_set("a", 1);
-
-  if (test_compaction) db->Flush(o);
-
-  assert(counters.assert_get("a") == 1);
-
-  counters.assert_remove("b");
-
-  // defaut value is 0 if non-existent
-  assert(counters.assert_get("b") == 0);
-
-  counters.assert_add("a", 2);
-
-  if (test_compaction) db->Flush(o);
-
-  // 1+2 = 3
-  assert(counters.assert_get("a")== 3);
-
-  dumpDb(db);
-
-  std::cout << "1\n";
-
-  // 1+...+49 = ?
-  uint64_t sum = 0;
-  for (int i = 1; i < 50; i++) {
-    counters.assert_add("b", i);
-    sum += i;
-  }
-  assert(counters.assert_get("b") == sum);
-
-  std::cout << "2\n";
-  dumpDb(db);
-
-  std::cout << "3\n";
-
-  if (test_compaction) {
-    db->Flush(o);
-
-    cout << "Compaction started ...\n";
-    db->CompactRange(nullptr, nullptr);
-    cout << "Compaction ended\n";
-
-    dumpDb(db);
-
-    assert(counters.assert_get("a")== 3);
-    assert(counters.assert_get("b") == sum);
-  }
-}
-
-void runTest(int argc, const string& dbname, const bool use_ttl = false) {
-  auto db = OpenDb(dbname, use_ttl);
-
-  {
-    cout << "Test read-modify-write counters... \n";
-    Counters counters(db, 0);
-    testCounters(counters, db.get(), true);
-  }
-
-  bool compact = false;
-  if (argc > 1) {
-    compact = true;
-    cout << "Turn on Compaction\n";
-  }
-
-  {
-    cout << "Test merge-based counters... \n";
-    MergeBasedCounters counters(db, 0);
-    testCounters(counters, db.get(), compact);
-  }
-
-  DestroyDB(dbname, Options());
-}
-
-int main(int argc, char *argv[]) {
-  //TODO: Make this test like a general rocksdb unit-test
-  runTest(argc, test::TmpDir() + "/merge_testdb");
-  runTest(argc, test::TmpDir() + "/merge_testdbttl", true); // Run test on TTL database
-  return 0;
-}
@@ -1,320 +0,0 @@
-#include <algorithm>
-#include <iostream>
-#include <vector>
-#include "/usr/include/valgrind/callgrind.h"
-
-#include "rocksdb/db.h"
-#include "rocksdb/perf_context.h"
-#include "util/histogram.h"
-#include "util/stop_watch.h"
-#include "util/testharness.h"
-
-
-bool FLAGS_random_key = false;
-bool FLAGS_use_set_based_memetable = false;
-int FLAGS_total_keys = 100;
-int FLAGS_write_buffer_size = 1000000000;
-int FLAGS_max_write_buffer_number = 8;
-int FLAGS_min_write_buffer_number_to_merge = 7;
-
-// Path to the database on file system
-const std::string kDbName = rocksdb::test::TmpDir() + "/perf_context_test";
-
-void SeekToFirst(rocksdb::Iterator* iter) {
-//  std::cout << "Press a key to continue:";
-//  std::string s;
-//  std::cin >> s;
-  iter->SeekToFirst();
-//  std::cout << "Press a key to continue:";
-//  std::string s2;
-//  std::cin >> s2;
-}
-
-namespace rocksdb {
-
-std::shared_ptr<DB> OpenDb() {
-    DB* db;
-    Options options;
-    options.create_if_missing = true;
-    options.write_buffer_size = FLAGS_write_buffer_size;
-    options.max_write_buffer_number = FLAGS_max_write_buffer_number;
-    options.min_write_buffer_number_to_merge =
-      FLAGS_min_write_buffer_number_to_merge;
-
-    if (FLAGS_use_set_based_memetable) {
-      auto prefix_extractor = rocksdb::NewFixedPrefixTransform(0);
-      options.memtable_factory =
-        std::make_shared<rocksdb::PrefixHashRepFactory>(prefix_extractor);
-    }
-
-    Status s = DB::Open(options, kDbName,  &db);
-    ASSERT_OK(s);
-    return std::shared_ptr<DB>(db);
-}
-
-class PerfContextTest { };
-
-TEST(PerfContextTest, SeekIntoDeletion) {
-  DestroyDB(kDbName, Options());
-  auto db = OpenDb();
-  WriteOptions write_options;
-  ReadOptions read_options;
-
-  for (int i = 0; i < FLAGS_total_keys; ++i) {
-    std::string key = "k" + std::to_string(i);
-    std::string value = "v" + std::to_string(i);
-
-    db->Put(write_options, key, value);
-  }
-
-  for (int i = 0; i < FLAGS_total_keys -1 ; ++i) {
-    std::string key = "k" + std::to_string(i);
-    db->Delete(write_options, key);
-  }
-
-  HistogramImpl hist_get;
-  HistogramImpl hist_get_time;
-  for (int i = 0; i < FLAGS_total_keys - 1; ++i) {
-    std::string key = "k" + std::to_string(i);
-    std::string value;
-
-    perf_context.Reset();
-    StopWatchNano timer(Env::Default(), true);
-    auto status = db->Get(read_options, key, &value);
-    auto elapsed_nanos = timer.ElapsedNanos();
-    ASSERT_TRUE(status.IsNotFound());
-    hist_get.Add(perf_context.user_key_comparison_count);
-    hist_get_time.Add(elapsed_nanos);
-  }
-
-  std::cout << "Get uesr key comparison: \n" << hist_get.ToString()
-            << "Get time: \n" << hist_get_time.ToString();
-
-  HistogramImpl hist_seek_to_first;
-  std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
-
-  perf_context.Reset();
-  StopWatchNano timer(Env::Default(), true);
-  //CALLGRIND_ZERO_STATS;
-  SeekToFirst(iter.get());
-  //iter->SeekToFirst();
-  //CALLGRIND_DUMP_STATS;
-  hist_seek_to_first.Add(perf_context.user_key_comparison_count);
-  auto elapsed_nanos = timer.ElapsedNanos();
-
-  std::cout << "SeekToFirst uesr key comparison: \n" << hist_seek_to_first.ToString()
-            << "ikey skipped: " << perf_context.internal_key_skipped_count << "\n"
-            << "idelete skipped: " << perf_context.internal_delete_skipped_count << "\n"
-            << "elapsed: " << elapsed_nanos << "\n";
-
-  HistogramImpl hist_seek;
-  for (int i = 0; i < FLAGS_total_keys; ++i) {
-    std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
-    std::string key = "k" + std::to_string(i);
-
-    perf_context.Reset();
-    StopWatchNano timer(Env::Default(), true);
-    iter->Seek(key);
-    auto elapsed_nanos = timer.ElapsedNanos();
-    hist_seek.Add(perf_context.user_key_comparison_count);
-    std::cout << "seek cmp: " << perf_context.user_key_comparison_count
-              << " ikey skipped " << perf_context.internal_key_skipped_count
-              << " idelete skipped " << perf_context.internal_delete_skipped_count
-              << " elapsed: " << elapsed_nanos << "ns\n";
-
-    perf_context.Reset();
-    ASSERT_TRUE(iter->Valid());
-    StopWatchNano timer2(Env::Default(), true);
-    iter->Next();
-    auto elapsed_nanos2 = timer2.ElapsedNanos();
-    std::cout << "next cmp: " << perf_context.user_key_comparison_count
-              << "elapsed: " << elapsed_nanos2 << "ns\n";
-  }
-
-  std::cout << "Seek uesr key comparison: \n" << hist_seek.ToString();
-}
-
-TEST(PerfContextTest, StopWatchNanoOverhead) {
-  // profile the timer cost by itself!
-  const int kTotalIterations = 1000000;
-  std::vector<uint64_t> timings(kTotalIterations);
-
-  StopWatchNano timer(Env::Default(), true);
-  for (auto& timing : timings) {
-    timing = timer.ElapsedNanos(true /* reset */);
-  }
-
-  HistogramImpl histogram;
-  for (const auto timing : timings) {
-    histogram.Add(timing);
-  }
-
-  std::cout << histogram.ToString();
-}
-
-TEST(PerfContextTest, StopWatchOverhead) {
-  // profile the timer cost by itself!
-  const int kTotalIterations = 1000000;
-  std::vector<uint64_t> timings(kTotalIterations);
-
-  StopWatch timer(Env::Default());
-  for (auto& timing : timings) {
-    timing = timer.ElapsedMicros();
-  }
-
-  HistogramImpl histogram;
-  uint64_t prev_timing = 0;
-  for (const auto timing : timings) {
-    histogram.Add(timing - prev_timing);
-    prev_timing = timing;
-  }
-
-  std::cout << histogram.ToString();
-}
-
-void ProfileKeyComparison() {
-  DestroyDB(kDbName, Options());    // Start this test with a fresh DB
-
-  auto db = OpenDb();
-
-  WriteOptions write_options;
-  ReadOptions read_options;
-
-  HistogramImpl hist_put;
-  HistogramImpl hist_get;
-
-  std::cout << "Inserting " << FLAGS_total_keys << " key/value pairs\n...\n";
-
-  std::vector<int> keys;
-  for (int i = 0; i < FLAGS_total_keys; ++i) {
-    keys.push_back(i);
-  }
-
-  if (FLAGS_random_key) {
-    std::random_shuffle(keys.begin(), keys.end());
-  }
-
-  for (const int i : keys) {
-    std::string key = "k" + std::to_string(i);
-    std::string value = "v" + std::to_string(i);
-
-    perf_context.Reset();
-    db->Put(write_options, key, value);
-    hist_put.Add(perf_context.user_key_comparison_count);
-
-    perf_context.Reset();
-    db->Get(read_options, key, &value);
-    hist_get.Add(perf_context.user_key_comparison_count);
-  }
-
-  std::cout << "Put uesr key comparison: \n" << hist_put.ToString()
-            << "Get uesr key comparison: \n" << hist_get.ToString();
-
-}
-
-TEST(PerfContextTest, KeyComparisonCount) {
-  SetPerfLevel(kEnableCount);
-  ProfileKeyComparison();
-
-  SetPerfLevel(kDisable);
-  ProfileKeyComparison();
-
-  SetPerfLevel(kEnableTime);
-  ProfileKeyComparison();
-}
-
-// make perf_context_test
-// export LEVELDB_TESTS=PerfContextTest.SeekKeyComparison
-// For one memtable:
-// ./perf_context_test --write_buffer_size=500000 --total_keys=10000
-// For two memtables:
-// ./perf_context_test --write_buffer_size=250000 --total_keys=10000
-// Specify --random_key=1 to shuffle the key before insertion
-// Results show that, for sequential insertion, worst-case Seek Key comparison
-// is close to the total number of keys (linear), when there is only one
-// memtable. When there are two memtables, even the avg Seek Key comparison
-// starts to become linear to the input size.
-
-TEST(PerfContextTest, SeekKeyComparison) {
-  DestroyDB(kDbName, Options());
-  auto db = OpenDb();
-  WriteOptions write_options;
-  ReadOptions read_options;
-
-  std::cout << "Inserting " << FLAGS_total_keys << " key/value pairs\n...\n";
-
-  std::vector<int> keys;
-  for (int i = 0; i < FLAGS_total_keys; ++i) {
-    keys.push_back(i);
-  }
-
-  if (FLAGS_random_key) {
-    std::random_shuffle(keys.begin(), keys.end());
-  }
-
-  for (const int i : keys) {
-    std::string key = "k" + std::to_string(i);
-    std::string value = "v" + std::to_string(i);
-
-    db->Put(write_options, key, value);
-  }
-
-  HistogramImpl hist_seek;
-  HistogramImpl hist_next;
-
-  for (int i = 0; i < FLAGS_total_keys; ++i) {
-    std::string key = "k" + std::to_string(i);
-    std::string value = "v" + std::to_string(i);
-
-    std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
-    perf_context.Reset();
-    iter->Seek(key);
-    ASSERT_TRUE(iter->Valid());
-    ASSERT_EQ(iter->value().ToString(), value);
-    hist_seek.Add(perf_context.user_key_comparison_count);
-  }
-
-  std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
-  for (iter->SeekToFirst(); iter->Valid();) {
-    perf_context.Reset();
-    iter->Next();
-    hist_next.Add(perf_context.user_key_comparison_count);
-  }
-
-  std::cout << "Seek:\n" << hist_seek.ToString()
-            << "Next:\n" << hist_next.ToString();
-}
-
-}
-
-int main(int argc, char** argv) {
-
-  for (int i = 1; i < argc; i++) {
-    int n;
-    char junk;
-
-    if (sscanf(argv[i], "--write_buffer_size=%d%c", &n, &junk) == 1) {
-      FLAGS_write_buffer_size = n;
-    }
-
-    if (sscanf(argv[i], "--total_keys=%d%c", &n, &junk) == 1) {
-      FLAGS_total_keys = n;
-    }
-
-    if (sscanf(argv[i], "--random_key=%d%c", &n, &junk) == 1 &&
-        (n == 0 || n == 1)) {
-      FLAGS_random_key = n;
-    }
-
-    if (sscanf(argv[i], "--use_set_based_memetable=%d%c", &n, &junk) == 1 &&
-        (n == 0 || n == 1)) {
-      FLAGS_use_set_based_memetable = n;
-    }
-
-  }
-
-  std::cout << kDbName << "\n";
-
-  rocksdb::test::RunAllTests();
-  return 0;
-}
@@ -1,76 +0,0 @@
-// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file. See the AUTHORS file for names of contributors.
-//
-// Wrap an underlying iterator, but exclude any results not starting
-// with a given prefix.  Seeking to keys not beginning with the prefix
-// is invalid, and SeekToLast is not implemented (that would be
-// non-trivial), but otherwise this iterator will behave just like the
-// underlying iterator would if there happened to be no non-matching
-// keys in the dataset.
-
-#ifndef STORAGE_LEVELDB_DB_PREFIX_FILTER_ITERATOR_H_
-#define STORAGE_LEVELDB_DB_PREFIX_FILTER_ITERATOR_H_
-
-#include "rocksdb/iterator.h"
-
-namespace rocksdb {
-
-class PrefixFilterIterator : public Iterator {
- private:
-  Iterator* iter_;
-  const Slice &prefix_;
-  const SliceTransform *prefix_extractor_;
-  Status status_;
-
- public:
-  PrefixFilterIterator(Iterator* iter,
-                       const Slice &prefix,
-                       const SliceTransform* prefix_extractor)
-                             : iter_(iter), prefix_(prefix),
-                               prefix_extractor_(prefix_extractor),
-                               status_(Status::OK()) {
-    if (prefix_extractor == nullptr) {
-      status_ = Status::InvalidArgument("A prefix filter may not be used "
-                                        "unless a function is also defined "
-                                        "for extracting prefixes");
-    } else if (!prefix_extractor_->InRange(prefix)) {
-      status_ = Status::InvalidArgument("Must provide a slice for prefix which"
-                                        "is a prefix for some key");
-    }
-  }
-  ~PrefixFilterIterator() {
-    delete iter_;
-  }
-  Slice key() const { return iter_->key(); }
-  Slice value() const { return iter_->value(); }
-  Status status() const {
-    if (!status_.ok()) {
-      return status_;
-    }
-    return iter_->status();
-  }
-  void Next() { iter_->Next(); }
-  void Prev() { iter_->Prev(); }
-  void Seek(const Slice& k) {
-    if (prefix_extractor_->Transform(k) == prefix_) {
-      iter_->Seek(k);
-    } else {
-      status_ = Status::InvalidArgument("Seek must begin with target prefix");
-    }
-  }
-  void SeekToFirst() {
-    Seek(prefix_);
-  }
-  void SeekToLast() {
-    status_ = Status::NotSupported("SeekToLast is incompatible with prefixes");
-  }
-  bool Valid() const {
-    return (status_.ok() && iter_->Valid() &&
-            prefix_extractor_->Transform(iter_->key()) == prefix_);
-  }
-};
-
-}  // namespace rocksdb
-
-#endif
@@ -34,11 +34,11 @@
 #include "db/table_cache.h"
 #include "db/version_edit.h"
 #include "db/write_batch_internal.h"
-#include "rocksdb/comparator.h"
-#include "rocksdb/db.h"
-#include "rocksdb/env.h"
+#include "leveldb/comparator.h"
+#include "leveldb/db.h"
+#include "leveldb/env.h"

-namespace rocksdb {
+namespace leveldb {

 namespace {

@@ -52,7 +52,7 @@ class Repairer {
        options_(SanitizeOptions(dbname, &icmp_, &ipolicy_, options)),
        next_file_number_(1) {
    // TableCache can be small since we expect each table to be opened once.
-    table_cache_ = new TableCache(dbname_, &options_, storage_options_, 10);
+    table_cache_ = new TableCache(dbname_, &options_, 10);
    edit_ = new VersionEdit(options.num_levels);
  }

@@ -88,7 +88,6 @@ class Repairer {
 private:
  struct TableInfo {
    FileMetaData meta;
-    SequenceNumber min_sequence;
    SequenceNumber max_sequence;
  };

@@ -106,7 +105,6 @@ class Repairer {
  std::vector<uint64_t> logs_;
  std::vector<TableInfo> tables_;
  uint64_t next_file_number_;
-  const EnvOptions storage_options_;

  Status FindFiles() {
    std::vector<std::string> filenames;
@@ -171,7 +169,7 @@ class Repairer {
    // Open the log file
    std::string logname = LogFileName(dbname_, log);
    unique_ptr<SequentialFile> lfile;
-    Status status = env_->NewSequentialFile(logname, &lfile, storage_options_);
+    Status status = env_->NewSequentialFile(logname, &lfile);
    if (!status.ok()) {
      return status;
    }
@@ -192,8 +190,7 @@ class Repairer {
    std::string scratch;
    Slice record;
    WriteBatch batch;
-    MemTable* mem = new MemTable(icmp_, options_.memtable_factory,
-      options_.num_levels);
+    MemTable* mem = new MemTable(icmp_, options_.num_levels);
    mem->Ref();
    int counter = 0;
    while (reader.ReadRecord(&record, &scratch)) {
@@ -219,8 +216,7 @@ class Repairer {
    FileMetaData meta;
    meta.number = next_file_number_++;
    Iterator* iter = mem->NewIterator();
-    status = BuildTable(dbname_, env_, options_, storage_options_,
-                        table_cache_, iter, &meta,
+    status = BuildTable(dbname_, env_, options_, table_cache_, iter, &meta,
                        icmp_.user_comparator(), 0, 0);
    delete iter;
    mem->Unref();
@@ -262,10 +258,9 @@ class Repairer {
    Status status = env_->GetFileSize(fname, &t->meta.file_size);
    if (status.ok()) {
      Iterator* iter = table_cache_->NewIterator(
-          ReadOptions(), storage_options_, t->meta.number, t->meta.file_size);
+          ReadOptions(), t->meta.number, t->meta.file_size);
      bool empty = true;
      ParsedInternalKey parsed;
-      t->min_sequence = 0;
      t->max_sequence = 0;
      for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
        Slice key = iter->key();
@@ -282,9 +277,6 @@ class Repairer {
          t->meta.smallest.DecodeFrom(key);
        }
        t->meta.largest.DecodeFrom(key);
-        if (parsed.sequence < t->min_sequence) {
-          t->min_sequence = parsed.sequence;
-        }
        if (parsed.sequence > t->max_sequence) {
          t->max_sequence = parsed.sequence;
        }
@@ -304,7 +296,7 @@ class Repairer {
  Status WriteDescriptor() {
    std::string tmp = TempFileName(dbname_, 1);
    unique_ptr<WritableFile> file;
-    Status status = env_->NewWritableFile(tmp, &file, storage_options_);
+    Status status = env_->NewWritableFile(tmp, &file);
    if (!status.ok()) {
      return status;
    }
@@ -325,8 +317,7 @@ class Repairer {
      // TODO(opt): separate out into multiple levels
      const TableInfo& t = tables_[i];
      edit_->AddFile(0, t.meta.number, t.meta.file_size,
-                    t.meta.smallest, t.meta.largest,
-                    t.min_sequence, t.max_sequence);
+                    t.meta.smallest, t.meta.largest);
    }

    //fprintf(stderr, "NewDescriptor:\n%s\n", edit_.DebugString().c_str());
@@ -383,4 +374,4 @@ Status RepairDB(const std::string& dbname, const Options& options) {
  return repairer.Run();
 }

-}  // namespace rocksdb
+}  // namespace leveldb
@@ -31,9 +31,12 @@
 #include <assert.h>
 #include <stdlib.h>
 #include "port/port.h"
+#include "util/arena.h"
 #include "util/random.h"

-namespace rocksdb {
+namespace leveldb {
+
+class Arena;

 template<typename Key, class Comparator>
 class SkipList {
@@ -107,7 +110,6 @@ class SkipList {

  // Used for optimizing sequential insert patterns
  Node* prev_[kMaxHeight];
-  int   prev_height_;

  inline int GetMaxHeight() const {
    return static_cast<int>(
@@ -268,10 +270,6 @@ typename SkipList<Key,Comparator>::Node* SkipList<Key,Comparator>::FindGreaterOr
    Node* x = prev[0];
    Node* next = x->Next(0);
    if ((x == head_) || KeyIsAfterNode(key, x)) {
-      // Adjust all relevant insertion points to the previous entry
-      for (int i = 1; i < prev_height_; i++) {
-        prev[i] = x;
-      }
      return next;
    }
  }
@@ -280,9 +278,6 @@ typename SkipList<Key,Comparator>::Node* SkipList<Key,Comparator>::FindGreaterOr
  int level = GetMaxHeight() - 1;
  while (true) {
    Node* next = x->Next(level);
-    // Make sure the lists are sorted.
-    // If x points to head_ or next points nullptr, it is trivially satisfied.
-    assert((x == head_) || (next == nullptr) || KeyIsAfterNode(next->key, x));
    if (KeyIsAfterNode(key, next)) {
      // Keep searching in this list
      x = next;
@@ -345,7 +340,6 @@ SkipList<Key,Comparator>::SkipList(Comparator cmp, Arena* arena)
      arena_(arena),
      head_(NewNode(0 /* any key will do */, kMaxHeight)),
      max_height_(reinterpret_cast<void*>(1)),
-      prev_height_(1),
      rnd_(0xdeadbeef) {
  for (int i = 0; i < kMaxHeight; i++) {
    head_->SetNext(i, nullptr);
@@ -387,7 +381,6 @@ void SkipList<Key,Comparator>::Insert(const Key& key) {
    prev_[i]->SetNext(i, x);
  }
  prev_[0] = x;
-  prev_height_ = height;
 }

 template<typename Key, class Comparator>
@@ -400,6 +393,6 @@ bool SkipList<Key,Comparator>::Contains(const Key& key) const {
  }
 }

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif // STORAGE_LEVELDB_DB_SKIPLIST_H_
@@ -4,13 +4,13 @@

 #include "db/skiplist.h"
 #include <set>
-#include "rocksdb/env.h"
-#include "util/arena_impl.h"
+#include "leveldb/env.h"
+#include "util/arena.h"
 #include "util/hash.h"
 #include "util/random.h"
 #include "util/testharness.h"

-namespace rocksdb {
+namespace leveldb {

 typedef uint64_t Key;

@@ -29,9 +29,9 @@ struct TestComparator {
 class SkipTest { };

 TEST(SkipTest, Empty) {
-  ArenaImpl arena_impl;
+  Arena arena;
  TestComparator cmp;
-  SkipList<Key, TestComparator> list(cmp, &arena_impl);
+  SkipList<Key, TestComparator> list(cmp, &arena);
  ASSERT_TRUE(!list.Contains(10));

  SkipList<Key, TestComparator>::Iterator iter(&list);
@@ -49,9 +49,9 @@ TEST(SkipTest, InsertAndLookup) {
  const int R = 5000;
  Random rnd(1000);
  std::set<Key> keys;
-  ArenaImpl arena_impl;
+  Arena arena;
  TestComparator cmp;
-  SkipList<Key, TestComparator> list(cmp, &arena_impl);
+  SkipList<Key, TestComparator> list(cmp, &arena);
  for (int i = 0; i < N; i++) {
    Key key = rnd.Next() % R;
    if (keys.insert(key).second) {
@@ -204,14 +204,14 @@ class ConcurrentTest {
  // Current state of the test
  State current_;

-  ArenaImpl arena_impl_;
+  Arena arena_;

  // SkipList is not protected by mu_.  We just use a single writer
  // thread to modify it.
  SkipList<Key, TestComparator> list_;

 public:
-  ConcurrentTest() : list_(TestComparator(), &arena_impl_) { }
+  ConcurrentTest() : list_(TestComparator(), &arena_) { }

  // REQUIRES: External synchronization
  void WriteStep(Random* rnd) {
@@ -371,8 +371,8 @@ TEST(SkipTest, Concurrent3) { RunConcurrent(3); }
 TEST(SkipTest, Concurrent4) { RunConcurrent(4); }
 TEST(SkipTest, Concurrent5) { RunConcurrent(5); }

-}  // namespace rocksdb
+}  // namespace leveldb

 int main(int argc, char** argv) {
-  return rocksdb::test::RunAllTests();
+  return leveldb::test::RunAllTests();
 }
@@ -5,9 +5,9 @@
 #ifndef STORAGE_LEVELDB_DB_SNAPSHOT_H_
 #define STORAGE_LEVELDB_DB_SNAPSHOT_H_

-#include "rocksdb/db.h"
+#include "leveldb/db.h"

-namespace rocksdb {
+namespace leveldb {

 class SnapshotList;

@@ -59,9 +59,12 @@ class SnapshotList {

  // retrieve all snapshot numbers. They are sorted in ascending order.
  void getAll(std::vector<SequenceNumber>& ret) {
-    if (empty()) return;
    SnapshotImpl* s = &list_;
+    if (empty()) return;
+    SequenceNumber prev __attribute__((unused)) = 0;
    while (s->next_ != &list_) {
+      assert(prev <= s->next_->number_);
+      assert(prev = s->next_->number_); // assignment
      ret.push_back(s->next_->number_);
      s = s ->next_;
    }
@@ -80,6 +83,6 @@ class SnapshotList {
  SnapshotImpl list_;
 };

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_SNAPSHOT_H_
@@ -6,16 +6,23 @@

 #include "db/filename.h"

-#include "rocksdb/statistics.h"
-#include "table/table.h"
+#include "leveldb/env.h"
+#include "leveldb/table.h"
+#include "leveldb/statistics.h"
 #include "util/coding.h"
-#include "util/stop_watch.h"

-namespace rocksdb {
+namespace leveldb {
+
+struct TableAndFile {
+  unique_ptr<Table> table;
+};
+
+static class Statistics* dbstatistics;

 static void DeleteEntry(const Slice& key, void* value) {
-  Table* table = reinterpret_cast<Table*>(value);
-  delete table;
+  TableAndFile* tf = reinterpret_cast<TableAndFile*>(value);
+  RecordTick(dbstatistics, NO_FILE_CLOSES);
+  delete tf;
 }

 static void UnrefEntry(void* arg1, void* arg2) {
@@ -26,44 +33,35 @@ static void UnrefEntry(void* arg1, void* arg2) {

 TableCache::TableCache(const std::string& dbname,
                       const Options* options,
-                       const EnvOptions& storage_options,
                       int entries)
    : env_(options->env),
      dbname_(dbname),
      options_(options),
-      storage_options_(storage_options),
-      cache_(NewLRUCache(entries, options->table_cache_numshardbits)) {}
+      cache_(NewLRUCache(entries, options->table_cache_numshardbits)) {
+  dbstatistics = options->statistics;
+}

 TableCache::~TableCache() {
 }

-Status TableCache::FindTable(const EnvOptions& toptions,
-                             uint64_t file_number, uint64_t file_size,
-                             Cache::Handle** handle, bool* table_io,
-                             const bool no_io) {
+Status TableCache::FindTable(uint64_t file_number, uint64_t file_size,
+                             Cache::Handle** handle, bool* tableIO) {
  Status s;
  char buf[sizeof(file_number)];
  EncodeFixed64(buf, file_number);
  Slice key(buf, sizeof(buf));
  *handle = cache_->Lookup(key);
  if (*handle == nullptr) {
-    if (no_io) { // Dont do IO and return a not-found status
-      return Status::Incomplete("Table not found in table_cache, no_io is set");
-    }
-    if (table_io != nullptr) {
-      *table_io = true;    // we had to do IO from storage
+    if (tableIO != nullptr) {
+      *tableIO = true;    // we had to do IO from storage
    }
    std::string fname = TableFileName(dbname_, file_number);
    unique_ptr<RandomAccessFile> file;
    unique_ptr<Table> table;
-    s = env_->NewRandomAccessFile(fname, &file, toptions);
+    s = env_->NewRandomAccessFile(fname, &file);
    RecordTick(options_->statistics, NO_FILE_OPENS);
    if (s.ok()) {
-      if (options_->advise_random_on_open) {
-        file->Hint(RandomAccessFile::RANDOM);
-      }
-      StopWatch sw(env_, options_->statistics, TABLE_OPEN_IO_MICROS);
-      s = Table::Open(*options_, toptions, std::move(file), file_size, &table);
+      s = Table::Open(*options_, std::move(file), file_size, &table);
    }

    if (!s.ok()) {
@@ -72,42 +70,36 @@ Status TableCache::FindTable(const EnvOptions& toptions,
      // We do not cache error results so that if the error is transient,
      // or somebody repairs the file, we recover automatically.
    } else {
+      TableAndFile* tf = new TableAndFile;
+      tf->table = std::move(table);
      assert(file.get() == nullptr);
-      *handle = cache_->Insert(key, table.release(), 1, &DeleteEntry);
+      *handle = cache_->Insert(key, tf, 1, &DeleteEntry);
    }
  }
  return s;
 }

 Iterator* TableCache::NewIterator(const ReadOptions& options,
-                                  const EnvOptions& toptions,
                                  uint64_t file_number,
                                  uint64_t file_size,
-                                  Table** tableptr,
-                                  bool for_compaction) {
+                                  Table** tableptr) {
  if (tableptr != nullptr) {
    *tableptr = nullptr;
  }

  Cache::Handle* handle = nullptr;
-  Status s = FindTable(toptions, file_number, file_size, &handle,
-                       nullptr, options.read_tier == kBlockCacheTier);
+  Status s = FindTable(file_number, file_size, &handle);
  if (!s.ok()) {
    return NewErrorIterator(s);
  }

  Table* table =
-    reinterpret_cast<Table*>(cache_->Value(handle));
+    reinterpret_cast<TableAndFile*>(cache_->Value(handle))->table.get();
  Iterator* result = table->NewIterator(options);
  result->RegisterCleanup(&UnrefEntry, cache_.get(), handle);
  if (tableptr != nullptr) {
    *tableptr = table;
  }
-
-  if (for_compaction) {
-    table->SetupForCompaction();
-  }
-
  return result;
 }

@@ -116,48 +108,23 @@ Status TableCache::Get(const ReadOptions& options,
                       uint64_t file_size,
                       const Slice& k,
                       void* arg,
-                       bool (*saver)(void*, const Slice&, const Slice&, bool),
-                       bool* table_io,
-                       void (*mark_key_may_exist)(void*)) {
+                       void (*saver)(void*, const Slice&, const Slice&, bool),
+                       bool* tableIO) {
  Cache::Handle* handle = nullptr;
-  Status s = FindTable(storage_options_, file_number, file_size,
-                       &handle, table_io,
-                       options.read_tier == kBlockCacheTier);
+  Status s = FindTable(file_number, file_size, &handle, tableIO);
  if (s.ok()) {
    Table* t =
-      reinterpret_cast<Table*>(cache_->Value(handle));
-    s = t->InternalGet(options, k, arg, saver, mark_key_may_exist);
+      reinterpret_cast<TableAndFile*>(cache_->Value(handle))->table.get();
+    s = t->InternalGet(options, k, arg, saver);
    cache_->Release(handle);
-  } else if (options.read_tier && s.IsIncomplete()) {
-    // Couldnt find Table in cache but treat as kFound if no_io set
-    (*mark_key_may_exist)(arg);
-    return Status::OK();
  }
  return s;
 }

-bool TableCache::PrefixMayMatch(const ReadOptions& options,
-                                uint64_t file_number,
-                                uint64_t file_size,
-                                const Slice& internal_prefix,
-                                bool* table_io) {
-  Cache::Handle* handle = nullptr;
-  Status s = FindTable(storage_options_, file_number,
-                       file_size, &handle, table_io);
-  bool may_match = true;
-  if (s.ok()) {
-    Table* t =
-      reinterpret_cast<Table*>(cache_->Value(handle));
-    may_match = t->PrefixMayMatch(internal_prefix);
-    cache_->Release(handle);
-  }
-  return may_match;
-}
-
 void TableCache::Evict(uint64_t file_number) {
  char buf[sizeof(file_number)];
  EncodeFixed64(buf, file_number);
  cache_->Erase(Slice(buf, sizeof(buf)));
 }

-}  // namespace rocksdb
+}  // namespace leveldb
@@ -10,19 +10,17 @@
 #include <string>
 #include <stdint.h>
 #include "db/dbformat.h"
-#include "rocksdb/env.h"
-#include "rocksdb/cache.h"
+#include "leveldb/cache.h"
+#include "leveldb/table.h"
 #include "port/port.h"
-#include "table/table.h"

-namespace rocksdb {
+namespace leveldb {

 class Env;

 class TableCache {
 public:
-  TableCache(const std::string& dbname, const Options* options,
-             const EnvOptions& storage_options, int entries);
+  TableCache(const std::string& dbname, const Options* options, int entries);
  ~TableCache();

  // Return an iterator for the specified file number (the corresponding
@@ -33,29 +31,19 @@ class TableCache {
  // the cache and should not be deleted, and is valid for as long as the
  // returned iterator is live.
  Iterator* NewIterator(const ReadOptions& options,
-                        const EnvOptions& toptions,
                        uint64_t file_number,
                        uint64_t file_size,
-                        Table** tableptr = nullptr,
-                        bool for_compaction = false);
+                        Table** tableptr = nullptr);

  // If a seek to internal key "k" in specified file finds an entry,
-  // call (*handle_result)(arg, found_key, found_value) repeatedly until
-  // it returns false.
+  // call (*handle_result)(arg, found_key, found_value).
  Status Get(const ReadOptions& options,
             uint64_t file_number,
             uint64_t file_size,
             const Slice& k,
             void* arg,
-             bool (*handle_result)(void*, const Slice&, const Slice&, bool),
-             bool* table_io,
-             void (*mark_key_may_exist)(void*) = nullptr);
-
-  // Determine whether the table may contain the specified prefix.  If
-  // the table index of blooms are not in memory, this may cause an I/O
-  bool PrefixMayMatch(const ReadOptions& options, uint64_t file_number,
-                      uint64_t file_size, const Slice& internal_prefix,
-                      bool* table_io);
+             void (*handle_result)(void*, const Slice&, const Slice&, bool),
+             bool* tableIO);

  // Evict any entry for the specified file number
  void Evict(uint64_t file_number);
@@ -64,14 +52,12 @@ class TableCache {
  Env* const env_;
  const std::string dbname_;
  const Options* options_;
-  const EnvOptions& storage_options_;
  std::shared_ptr<Cache> cache_;

-  Status FindTable(const EnvOptions& toptions, uint64_t file_number,
-                   uint64_t file_size, Cache::Handle**, bool* table_io=nullptr,
-                   const bool no_io = false);
+  Status FindTable(uint64_t file_number, uint64_t file_size, Cache::Handle**,
+                   bool* tableIO = nullptr);
 };

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_TABLE_CACHE_H_
@@ -1,171 +0,0 @@
-#include "db/transaction_log_impl.h"
-#include "db/write_batch_internal.h"
-
-namespace rocksdb {
-
-TransactionLogIteratorImpl::TransactionLogIteratorImpl(
-                           const std::string& dbname,
-                           const Options* options,
-                           const EnvOptions& soptions,
-                           const SequenceNumber seq,
-                           std::unique_ptr<VectorLogPtr> files,
-                           SequenceNumber const * const lastFlushedSequence) :
-    dbname_(dbname),
-    options_(options),
-    soptions_(soptions),
-    startingSequenceNumber_(seq),
-    files_(std::move(files)),
-    started_(false),
-    isValid_(false),
-    currentFileIndex_(0),
-    lastFlushedSequence_(lastFlushedSequence) {
-  assert(startingSequenceNumber_ <= *lastFlushedSequence_);
-  assert(files_.get() != nullptr);
-
-  reporter_.env = options_->env;
-  reporter_.info_log = options_->info_log.get();
-}
-
-Status TransactionLogIteratorImpl::OpenLogFile(
-  const LogFile* logFile,
-  unique_ptr<SequentialFile>* file) {
-  Env* env = options_->env;
-  if (logFile->Type() == kArchivedLogFile) {
-    std::string fname = ArchivedLogFileName(dbname_, logFile->LogNumber());
-    return env->NewSequentialFile(fname, file, soptions_);
-  } else {
-    std::string fname = LogFileName(dbname_, logFile->LogNumber());
-    Status status = env->NewSequentialFile(fname, file, soptions_);
-    if (!status.ok()) {
-      //  If cannot open file in DB directory.
-      //  Try the archive dir, as it could have moved in the meanwhile.
-      fname = ArchivedLogFileName(dbname_, logFile->LogNumber());
-      status = env->NewSequentialFile(fname, file, soptions_);
-      if (!status.ok()) {
-        return Status::IOError(" Requested file not present in the dir");
-      }
-    }
-    return status;
-  }
-}
-
-BatchResult TransactionLogIteratorImpl::GetBatch()  {
-  assert(isValid_);  //  cannot call in a non valid state.
-  BatchResult result;
-  result.sequence = currentSequence_;
-  result.writeBatchPtr = std::move(currentBatch_);
-  return result;
-}
-
-Status TransactionLogIteratorImpl::status() {
-  return currentStatus_;
-}
-
-bool TransactionLogIteratorImpl::Valid() {
-  return started_ && isValid_;
-}
-
-void TransactionLogIteratorImpl::Next() {
-  LogFile* currentLogFile = files_.get()->at(currentFileIndex_).get();
-
-//  First seek to the given seqNo. in the current file.
-  std::string scratch;
-  Slice record;
-  if (!started_) {
-    started_ = true;  // this piece only runs onced.
-    isValid_ = false;
-    if (startingSequenceNumber_ > *lastFlushedSequence_) {
-      currentStatus_ = Status::IOError("Looking for a sequence, "
-                                        "which is not flushed yet.");
-      return;
-    }
-    Status s = OpenLogReader(currentLogFile);
-    if (!s.ok()) {
-      currentStatus_ = s;
-      isValid_ = false;
-      return;
-    }
-    while (currentLogReader_->ReadRecord(&record, &scratch)) {
-      if (record.size() < 12) {
-        reporter_.Corruption(
-          record.size(), Status::Corruption("log record too small"));
-        continue;
-      }
-      UpdateCurrentWriteBatch(record);
-      if (currentSequence_ >= startingSequenceNumber_) {
-        assert(currentSequence_ <= *lastFlushedSequence_);
-        isValid_ = true;
-        break;
-      } else {
-        isValid_ = false;
-      }
-    }
-    if (isValid_) {
-      // Done for this iteration
-      return;
-    }
-  }
-  bool openNextFile = true;
-  while(openNextFile) {
-    assert(currentLogReader_);
-    if (currentSequence_ < *lastFlushedSequence_) {
-      if (currentLogReader_->IsEOF()) {
-        currentLogReader_->UnmarkEOF();
-      }
-      while (currentLogReader_->ReadRecord(&record, &scratch)) {
-        if (record.size() < 12) {
-          reporter_.Corruption(
-            record.size(), Status::Corruption("log record too small"));
-          continue;
-        } else {
-          UpdateCurrentWriteBatch(record);
-          openNextFile = false;
-          break;
-        }
-      }
-    }
-
-    if (openNextFile) {
-      if (currentFileIndex_ < files_.get()->size() - 1) {
-        ++currentFileIndex_;
-        Status status =OpenLogReader(files_.get()->at(currentFileIndex_).get());
-        if (!status.ok()) {
-          isValid_ = false;
-          currentStatus_ = status;
-          return;
-        }
-      } else {
-        isValid_ = false;
-        openNextFile = false;
-        if (currentSequence_ == *lastFlushedSequence_) {
-          currentStatus_ = Status::OK();
-        } else {
-          currentStatus_ = Status::IOError(" NO MORE DATA LEFT");
-        }
-      }
-    }
-  }
-}
-
-void TransactionLogIteratorImpl::UpdateCurrentWriteBatch(const Slice& record) {
-  WriteBatch* batch = new WriteBatch();
-  WriteBatchInternal::SetContents(batch, record);
-  currentSequence_ = WriteBatchInternal::Sequence(batch);
-  currentBatch_.reset(batch);
-  isValid_ = true;
-  currentStatus_ = Status::OK();
-}
-
-Status TransactionLogIteratorImpl::OpenLogReader(const LogFile* logFile) {
-  unique_ptr<SequentialFile> file;
-  Status status = OpenLogFile(logFile, &file);
-  if (!status.ok()) {
-    return status;
-  }
-  assert(file);
-  currentLogReader_.reset(
-    new log::Reader(std::move(file), &reporter_, true, 0)
-  );
-  return Status::OK();
-}
-}  //  namespace rocksdb
@@ -1,103 +0,0 @@
-// Copyright 2008-present Facebook. All Rights Reserved.
-#ifndef STORAGE_LEVELDB_INCLUDE_WRITES_ITERATOR_IMPL_H_
-#define STORAGE_LEVELDB_INCLUDE_WRITES_ITERATOR_IMPL_H_
-
-#include <vector>
-
-#include "rocksdb/env.h"
-#include "rocksdb/options.h"
-#include "rocksdb/types.h"
-#include "rocksdb/transaction_log.h"
-#include "db/log_reader.h"
-#include "db/filename.h"
-
-namespace rocksdb {
-
-struct LogReporter : public log::Reader::Reporter {
-  Env* env;
-  Logger* info_log;
-  virtual void Corruption(size_t bytes, const Status& s) {
-    Log(info_log, "dropping %zu bytes; %s", bytes, s.ToString().c_str());
-  }
-};
-
-class LogFileImpl : public LogFile {
- public:
-  LogFileImpl(uint64_t logNum, WalFileType logType, SequenceNumber startSeq,
-              uint64_t sizeBytes) :
-    logNumber_(logNum),
-    type_(logType),
-    startSequence_(startSeq),
-    sizeFileBytes_(sizeBytes) {
-  }
-
-  std::string PathName() const {
-    if (type_ == kArchivedLogFile) {
-      return ArchivedLogFileName("", logNumber_);
-    }
-    return LogFileName("", logNumber_);
-  }
-
-  uint64_t LogNumber() const { return logNumber_; }
-
-  WalFileType Type() const { return type_; }
-
-  SequenceNumber StartSequence() const { return startSequence_; }
-
-  uint64_t SizeFileBytes() const { return sizeFileBytes_; }
-
-  bool operator < (const LogFile& that) const {
-    return LogNumber() < that.LogNumber();
-  }
-
- private:
-  uint64_t logNumber_;
-  WalFileType type_;
-  SequenceNumber startSequence_;
-  uint64_t sizeFileBytes_;
-
-};
-
-class TransactionLogIteratorImpl : public TransactionLogIterator {
- public:
-  TransactionLogIteratorImpl(const std::string& dbname,
-                             const Options* options,
-                             const EnvOptions& soptions,
-                             const SequenceNumber seqNum,
-                             std::unique_ptr<VectorLogPtr> files,
-                             SequenceNumber const * const lastFlushedSequence);
-
-  virtual bool Valid();
-
-  virtual void Next();
-
-  virtual Status status();
-
-  virtual BatchResult GetBatch();
-
- private:
-  const std::string& dbname_;
-  const Options* options_;
-  const EnvOptions& soptions_;
-  const SequenceNumber startingSequenceNumber_;
-  std::unique_ptr<VectorLogPtr> files_;
-  bool started_;
-  bool isValid_;  // not valid when it starts of.
-  Status currentStatus_;
-  size_t currentFileIndex_;
-  std::unique_ptr<WriteBatch> currentBatch_;
-  unique_ptr<log::Reader> currentLogReader_;
-  Status OpenLogFile(const LogFile* logFile, unique_ptr<SequentialFile>* file);
-  LogReporter reporter_;
-  SequenceNumber const * const lastFlushedSequence_;
-  // represents the sequence number being read currently.
-  SequenceNumber currentSequence_;
-
-  void UpdateCurrentWriteBatch(const Slice& record);
-  Status OpenLogReader(const LogFile* file);
-};
-
-
-
-}  //  namespace rocksdb
-#endif  //  STORAGE_LEVELDB_INCLUDE_WRITES_ITERATOR_IMPL_H_
@@ -0,0 +1,172 @@
+#include "db/transaction_log_iterator_impl.h"
+#include "db/write_batch_internal.h"
+#include "db/filename.h"
+namespace leveldb {
+
+TransactionLogIteratorImpl::TransactionLogIteratorImpl(
+                           const std::string& dbname,
+                           const Options* options,
+                           SequenceNumber& seq,
+                           std::vector<LogFile>* files,
+                           SequenceNumber const * const lastFlushedSequence) :
+  dbname_(dbname),
+  options_(options),
+  sequenceNumber_(seq),
+  files_(files),
+  started_(false),
+  isValid_(true),
+  currentFileIndex_(0),
+  lastFlushedSequence_(lastFlushedSequence) {
+  assert(files_ != nullptr);
+  assert(lastFlushedSequence_);
+}
+
+LogReporter
+TransactionLogIteratorImpl::NewLogReporter(const uint64_t logNumber) {
+  LogReporter reporter;
+  reporter.env = options_->env;
+  reporter.info_log = options_->info_log.get();
+  reporter.log_number = logNumber;
+  return reporter;
+}
+
+Status TransactionLogIteratorImpl::OpenLogFile(
+  const LogFile& logFile,
+  unique_ptr<SequentialFile>* file) {
+  Env* env = options_->env;
+  if (logFile.type == kArchivedLogFile) {
+    std::string fname = ArchivedLogFileName(dbname_, logFile.logNumber);
+    return env->NewSequentialFile(fname, file);
+  } else {
+    std::string fname = LogFileName(dbname_, logFile.logNumber);
+    Status status = env->NewSequentialFile(fname, file);
+    if (!status.ok()) {
+      //  If cannot open file in DB directory.
+      //  Try the archive dir, as it could have moved in the meanwhile.
+      fname = ArchivedLogFileName(dbname_, logFile.logNumber);
+      status = env->NewSequentialFile(fname, file);
+      if (!status.ok()) {
+        return Status::IOError(" Requested file not present in the dir");
+      }
+    }
+    return status;
+  }
+}
+
+BatchResult TransactionLogIteratorImpl::GetBatch()  {
+  assert(isValid_);  //  cannot call in a non valid state.
+  BatchResult result;
+  result.sequence = currentSequence_;
+  result.writeBatchPtr = std::move(currentBatch_);
+  return result;
+}
+
+Status TransactionLogIteratorImpl::status() {
+  return currentStatus_;
+}
+
+bool TransactionLogIteratorImpl::Valid() {
+  return started_ && isValid_;
+}
+
+void TransactionLogIteratorImpl::Next() {
+//  First seek to the given seqNo. in the current file.
+  LogFile currentLogFile = files_->at(currentFileIndex_);
+  LogReporter reporter = NewLogReporter(currentLogFile.logNumber);
+  std::string scratch;
+  Slice record;
+
+  if (!started_) {
+    isValid_ = false;
+    if (sequenceNumber_ > *lastFlushedSequence_) {
+      currentStatus_ = Status::IOError("Looking for a sequence, "
+                                        "which is not flushed yet.");
+      return;
+    }
+    unique_ptr<SequentialFile> file;
+    Status status = OpenLogFile(currentLogFile, &file);
+    if (!status.ok()) {
+      currentStatus_ = status;
+      return;
+    }
+    assert(file);
+    unique_ptr<log::Reader> reader(
+      new log::Reader(std::move(file), &reporter, true, 0));
+    assert(reader);
+    while (reader->ReadRecord(&record, &scratch)) {
+      if (record.size() < 12) {
+        reporter.Corruption(
+          record.size(), Status::Corruption("log record too small"));
+        continue;
+      }
+      UpdateCurrentWriteBatch(record);
+      if (currentSequence_ >= sequenceNumber_) {
+        assert(currentSequence_ < *lastFlushedSequence_);
+        isValid_ = true;
+        currentLogReader_ = std::move(reader);
+        break;
+      }
+    }
+    if (!isValid_) {
+      //  TODO read the entire first file. and did not find the seq number.
+      //  Error out.
+      currentStatus_ =
+        Status::NotFound("Did not find the Seq no. in first file");
+    }
+    started_ = true;
+  } else {
+LOOK_NEXT_FILE:
+    assert(currentLogReader_);
+    bool openNextFile = true;
+
+    if (currentSequence_ == *lastFlushedSequence_) {
+      // The last update has been read. and next is being called.
+      isValid_ = false;
+      currentStatus_ = Status::OK();
+    }
+
+    while (currentLogReader_->ReadRecord(&record, &scratch) &&
+           currentSequence_ < *lastFlushedSequence_) {
+      if (record.size() < 12) {
+        reporter.Corruption(
+          record.size(), Status::Corruption("log record too small"));
+        continue;
+      } else {
+        UpdateCurrentWriteBatch(record);
+        openNextFile = false;
+        break;
+      }
+    }
+
+    if (openNextFile) {
+      if (currentFileIndex_ < files_->size() - 1) {
+        ++currentFileIndex_;
+        currentLogReader_.reset();
+        unique_ptr<SequentialFile> file;
+        Status status = OpenLogFile(files_->at(currentFileIndex_), &file);
+        if (!status.ok()) {
+          isValid_ = false;
+          currentStatus_ = status;
+          return;
+        }
+        currentLogReader_.reset(
+          new log::Reader(std::move(file), &reporter, true, 0));
+        goto LOOK_NEXT_FILE;
+      } else {
+        //  LOOKED AT FILES. WE ARE DONE HERE.
+        isValid_ = false;
+        currentStatus_ = Status::IOError(" NO MORE DATA LEFT");
+      }
+    }
+
+  }
+}
+
+void TransactionLogIteratorImpl::UpdateCurrentWriteBatch(const Slice& record) {
+  WriteBatch* batch = new WriteBatch();
+  WriteBatchInternal::SetContents(batch, record);
+  currentSequence_ = WriteBatchInternal::Sequence(batch);
+  currentBatch_.reset(batch);
+}
+
+}  //  namespace leveldb
@@ -0,0 +1,70 @@
+// Copyright 2008-present Facebook. All Rights Reserved.
+#ifndef STORAGE_LEVELDB_INCLUDE_WRITES_ITERATOR_IMPL_H_
+#define STORAGE_LEVELDB_INCLUDE_WRITES_ITERATOR_IMPL_H_
+
+#include <vector>
+
+#include "leveldb/env.h"
+#include "leveldb/options.h"
+#include "leveldb/types.h"
+#include "leveldb/transaction_log_iterator.h"
+#include "db/log_file.h"
+#include "db/log_reader.h"
+
+namespace leveldb {
+
+struct LogReporter : public log::Reader::Reporter {
+  Env* env;
+  Logger* info_log;
+  uint64_t log_number;
+  virtual void Corruption(size_t bytes, const Status& s) {
+    Log(info_log, "%ld: dropping %d bytes; %s",
+        log_number, static_cast<int>(bytes), s.ToString().c_str());
+  }
+};
+
+class TransactionLogIteratorImpl : public TransactionLogIterator {
+ public:
+  TransactionLogIteratorImpl(const std::string& dbname,
+                             const Options* options,
+                             SequenceNumber& seqNum,
+                             std::vector<LogFile>* files,
+                             SequenceNumber const * const lastFlushedSequence);
+
+  virtual ~TransactionLogIteratorImpl() {
+    //  TODO move to cc file.
+    delete files_;
+  }
+
+  virtual bool Valid();
+
+  virtual void Next();
+
+  virtual Status status();
+
+  virtual BatchResult GetBatch();
+
+ private:
+  const std::string& dbname_;
+  const Options* options_;
+  const uint64_t sequenceNumber_;
+  const std::vector<LogFile>* files_;
+  bool started_;
+  bool isValid_;  // not valid when it starts of.
+  Status currentStatus_;
+  size_t currentFileIndex_;
+  std::unique_ptr<WriteBatch> currentBatch_;
+  unique_ptr<log::Reader> currentLogReader_;
+  Status OpenLogFile(const LogFile& logFile, unique_ptr<SequentialFile>* file);
+  LogReporter NewLogReporter(uint64_t logNumber);
+  SequenceNumber const * const lastFlushedSequence_;
+  // represents the sequence number being read currently.
+  SequenceNumber currentSequence_;
+
+  void UpdateCurrentWriteBatch(const Slice& record);
+};
+
+
+
+}  //  namespace leveldb
+#endif  //  STORAGE_LEVELDB_INCLUDE_WRITES_ITERATOR_IMPL_H_
@@ -7,7 +7,7 @@
 #include "db/version_set.h"
 #include "util/coding.h"

-namespace rocksdb {
+namespace leveldb {

 // Tag numbers for serialized VersionEdit.  These numbers are written to
 // disk and should not be changed.
@@ -20,10 +20,7 @@ enum Tag {
  kDeletedFile          = 6,
  kNewFile              = 7,
  // 8 was used for large value refs
-  kPrevLogNumber        = 9,
-
-  // these are new formats divergent from open source leveldb
-  kNewFile2             = 100  // store smallest & largest seqno
+  kPrevLogNumber        = 9
 };

 void VersionEdit::Clear() {
@@ -79,14 +76,12 @@ void VersionEdit::EncodeTo(std::string* dst) const {

  for (size_t i = 0; i < new_files_.size(); i++) {
    const FileMetaData& f = new_files_[i].second;
-    PutVarint32(dst, kNewFile2);
+    PutVarint32(dst, kNewFile);
    PutVarint32(dst, new_files_[i].first);  // level
    PutVarint64(dst, f.number);
    PutVarint64(dst, f.file_size);
    PutLengthPrefixedSlice(dst, f.smallest.Encode());
    PutLengthPrefixedSlice(dst, f.largest.Encode());
-    PutVarint64(dst, f.smallest_seqno);
-    PutVarint64(dst, f.largest_seqno);
  }
 }

@@ -206,22 +201,6 @@ Status VersionEdit::DecodeFrom(const Slice& src) {
        }
        break;

-      case kNewFile2:
-        if (GetLevel(&input, &level, &msg) &&
-            GetVarint64(&input, &f.number) &&
-            GetVarint64(&input, &f.file_size) &&
-            GetInternalKey(&input, &f.smallest) &&
-            GetInternalKey(&input, &f.largest) &&
-            GetVarint64(&input, &f.smallest_seqno) &&
-            GetVarint64(&input, &f.largest_seqno) ) {
-          new_files_.push_back(std::make_pair(level, f));
-        } else {
-          if (!msg) {
-            msg = "new-file2 entry";
-          }
-        }
-        break;
-
      default:
        msg = "unknown tag";
        break;
@@ -239,7 +218,7 @@ Status VersionEdit::DecodeFrom(const Slice& src) {
  return result;
 }

-std::string VersionEdit::DebugString(bool hex_key) const {
+std::string VersionEdit::DebugString() const {
  std::string r;
  r.append("VersionEdit {");
  if (has_comparator_) {
@@ -266,7 +245,7 @@ std::string VersionEdit::DebugString(bool hex_key) const {
    r.append("\n  CompactPointer: ");
    AppendNumberTo(&r, compact_pointers_[i].first);
    r.append(" ");
-    r.append(compact_pointers_[i].second.DebugString(hex_key));
+    r.append(compact_pointers_[i].second.DebugString());
  }
  for (DeletedFileSet::const_iterator iter = deleted_files_.begin();
       iter != deleted_files_.end();
@@ -285,12 +264,12 @@ std::string VersionEdit::DebugString(bool hex_key) const {
    r.append(" ");
    AppendNumberTo(&r, f.file_size);
    r.append(" ");
-    r.append(f.smallest.DebugString(hex_key));
+    r.append(f.smallest.DebugString());
    r.append(" .. ");
-    r.append(f.largest.DebugString(hex_key));
+    r.append(f.largest.DebugString());
  }
  r.append("\n}\n");
  return r;
 }

-}  // namespace rocksdb
+}  // namespace leveldb
@@ -10,7 +10,7 @@
 #include <vector>
 #include "db/dbformat.h"

-namespace rocksdb {
+namespace leveldb {

 class VersionSet;

@@ -22,8 +22,6 @@ struct FileMetaData {
  InternalKey smallest;       // Smallest internal key served by table
  InternalKey largest;        // Largest internal key served by table
  bool being_compacted;       // Is this file undergoing compaction?
-  SequenceNumber smallest_seqno;// The smallest seqno in this file
-  SequenceNumber largest_seqno; // The largest seqno in this file

  FileMetaData() : refs(0), allowed_seeks(1 << 30), file_size(0),
                   being_compacted(false) { }
@@ -69,17 +67,12 @@ class VersionEdit {
  void AddFile(int level, uint64_t file,
               uint64_t file_size,
               const InternalKey& smallest,
-               const InternalKey& largest,
-               const SequenceNumber& smallest_seqno,
-               const SequenceNumber& largest_seqno) {
+               const InternalKey& largest) {
    FileMetaData f;
    f.number = file;
    f.file_size = file_size;
    f.smallest = smallest;
    f.largest = largest;
-    f.smallest_seqno = smallest_seqno;
-    f.largest_seqno = largest_seqno;
-    assert(smallest_seqno <= largest_seqno);
    new_files_.push_back(std::make_pair(level, f));
  }

@@ -88,15 +81,10 @@ class VersionEdit {
    deleted_files_.insert(std::make_pair(level, file));
  }

-  // Number of edits
-  int NumEntries() {
-    return new_files_.size() + deleted_files_.size();
-  }
-
  void EncodeTo(std::string* dst) const;
  Status DecodeFrom(const Slice& src);

-  std::string DebugString(bool hex_key = false) const;
+  std::string DebugString() const;

 private:
  friend class VersionSet;
@@ -122,6 +110,6 @@ class VersionEdit {
  std::vector< std::pair<int, FileMetaData> > new_files_;
 };

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_VERSION_EDIT_H_
@@ -5,7 +5,7 @@
 #include "db/version_edit.h"
 #include "util/testharness.h"

-namespace rocksdb {
+namespace leveldb {

 static void TestEncodeDecode(const VersionEdit& edit) {
  std::string encoded, encoded2;
@@ -27,9 +27,7 @@ TEST(VersionEditTest, EncodeDecode) {
    TestEncodeDecode(edit);
    edit.AddFile(3, kBig + 300 + i, kBig + 400 + i,
                 InternalKey("foo", kBig + 500 + i, kTypeValue),
-                 InternalKey("zoo", kBig + 600 + i, kTypeDeletion),
-                 kBig + 500 + i,
-                 kBig + 600 + i);
+                 InternalKey("zoo", kBig + 600 + i, kTypeDeletion));
    edit.DeleteFile(4, kBig + 700 + i);
    edit.SetCompactPointer(i, InternalKey("x", kBig + 900 + i, kTypeValue));
  }
@@ -41,8 +39,8 @@ TEST(VersionEditTest, EncodeDecode) {
  TestEncodeDecode(edit);
 }

-}  // namespace rocksdb
+}  // namespace leveldb

 int main(int argc, char** argv) {
-  return rocksdb::test::RunAllTests();
+  return leveldb::test::RunAllTests();
 }
@@ -25,7 +25,7 @@
 #include "port/port.h"
 #include "db/table_cache.h"

-namespace rocksdb {
+namespace leveldb {

 namespace log { class Writer; }

@@ -63,21 +63,17 @@ class Version {
  // Append to *iters a sequence of iterators that will
  // yield the contents of this Version when merged together.
  // REQUIRES: This version has been saved (see VersionSet::SaveTo)
-  void AddIterators(const ReadOptions&, const EnvOptions& soptions,
-                    std::vector<Iterator*>* iters);
+  void AddIterators(const ReadOptions&, std::vector<Iterator*>* iters);

  // Lookup the value for key.  If found, store it in *val and
  // return OK.  Else return a non-OK status.  Fills *stats.
-  // Uses *operands to store merge_operator operations to apply later
  // REQUIRES: lock is not held
  struct GetStats {
    FileMetaData* seek_file;
    int seek_file_level;
  };
-  void Get(const ReadOptions&, const LookupKey& key, std::string* val,
-           Status* status, std::deque<std::string>* operands, GetStats* stats,
-           const Options& db_option,
-           bool* value_found = nullptr);
+  Status Get(const ReadOptions&, const LookupKey& key, std::string* val,
+             GetStats* stats);

  // Adds "stats" into the current state.  Returns true if a new
  // compaction may need to be triggered, false otherwise.
@@ -110,7 +106,7 @@ class Version {
      const Slice& begin,         // nullptr means before all keys
      const Slice& end,           // nullptr means after all keys
      std::vector<FileMetaData*>* inputs,
-      unsigned int index);                 // start extending from this index
+      int index);                 // start extending from this index

  // Returns true iff some file in the specified level overlaps
  // some part of [*smallest_user_key,*largest_user_key].
@@ -120,14 +116,6 @@ class Version {
                      const Slice* smallest_user_key,
                      const Slice* largest_user_key);

-  // Returns true iff the first or last file in inputs contains
-  // an overlapping user key to the file "just outside" of it (i.e.
-  // just after the last file, or just before the first file)
-  // REQUIRES: "*inputs" is a sorted list of non-overlapping files
-  bool HasOverlappingUserKey(const std::vector<FileMetaData*>* inputs,
-                             int level);
-
-
  // Return the level at which we should place a new memtable compaction
  // result that covers the range [smallest_user_key,largest_user_key].
  int PickLevelForMemTableOutput(const Slice& smallest_user_key,
@@ -146,14 +134,9 @@ class Version {
 private:
  friend class Compaction;
  friend class VersionSet;
-  friend class DBImpl;

  class LevelFileNumIterator;
-  Iterator* NewConcatenatingIterator(const ReadOptions&,
-                                     const EnvOptions& soptions,
-                                     int level) const;
-  bool PrefixMayMatch(const ReadOptions& options, const EnvOptions& soptions,
-                      const Slice& internal_prefix, Iterator* level_iter) const;
+  Iterator* NewConcatenatingIterator(const ReadOptions&, int level) const;

  VersionSet* vset_;            // VersionSet to which this Version belongs
  Version* next_;               // Next version in linked list
@@ -221,7 +204,6 @@ class VersionSet {
 public:
  VersionSet(const std::string& dbname,
             const Options* options,
-             const EnvOptions& storage_options,
             TableCache* table_cache,
             const InternalKeyComparator*);
  ~VersionSet();
@@ -340,7 +322,8 @@ class VersionSet {
  }

  // Add all files listed in any live version to *live.
-  void AddLiveFiles(std::vector<uint64_t>* live_list);
+  // May also mutate some internal state.
+  void AddLiveFiles(std::set<uint64_t>* live);

  // Add all files listed in the current version to *live.
  void AddLiveFilesCurrentVersion(std::set<uint64_t>* live);
@@ -354,9 +337,6 @@ class VersionSet {
  struct LevelSummaryStorage {
    char buffer[100];
  };
-  struct FileSummaryStorage {
-    char buffer[1000];
-  };
  const char* LevelSummary(LevelSummaryStorage* scratch) const;

  // printf contents (for debugging)
@@ -367,10 +347,6 @@ class VersionSet {
  // of files per level.  Uses *scratch as backing store.
  const char* LevelDataSizeSummary(LevelSummaryStorage* scratch) const;

-  // Return a human-readable short (single-line) summary of files
-  // in a specified level.  Uses *scratch as backing store.
-  const char* LevelFileSummary(FileSummaryStorage* scratch, int level) const;
-
  // Return the size of the current manifest file
  const uint64_t ManifestFileSize() { return current_->offset_manifest_file_; }

@@ -380,16 +356,6 @@ class VersionSet {
  // function will return nullptr.
  Compaction* PickCompactionBySize(int level, double score);

-  // Pick files to compact in Universal mode
-  Compaction* PickCompactionUniversal(int level, double score);
-
-  // Pick Universal compaction to limit read amplification
-  Compaction* PickCompactionUniversalReadAmp(int level, double score,
-                unsigned int ratio, unsigned int num_files);
-
-  // Pick Universal compaction to limit space amplification.
-  Compaction* PickCompactionUniversalSizeAmp(int level, double score);
-
  // Free up the files that were participated in a compaction
  void ReleaseCompactionFiles(Compaction* c, Status status);

@@ -412,14 +378,6 @@ class VersionSet {
  // Get the max file size in a given level.
  uint64_t MaxFileSizeForLevel(int level);

-  double MaxBytesForLevel(int level);
-
-  Status GetMetadataForFile(
-    uint64_t number, int *filelevel, FileMetaData *metadata);
-
-  void GetLiveFilesMetaData(
-    std::vector<LiveFileMetaData> *metadata);
-
 private:
  class Builder;
  struct ManifestWriter;
@@ -440,8 +398,6 @@ class VersionSet {
                 InternalKey* smallest,
                 InternalKey* largest);

-  void ExpandWhileOverlapping(Compaction* c);
-
  void SetupOtherInputs(Compaction* c);

  // Save current contents to *log
@@ -451,9 +407,11 @@ class VersionSet {

  bool ManifestContains(const std::string& record) const;

-  uint64_t ExpandedCompactionByteSizeLimit(int level);
+  double MaxBytesForLevel(int level);

-  uint64_t MaxGrandParentOverlapBytes(int level);
+  int64_t ExpandedCompactionByteSizeLimit(int level);
+
+  int64_t MaxGrandParentOverlapBytes(int level);

  Env* const env_;
  const std::string dbname_;
@@ -496,13 +454,6 @@ class VersionSet {
  // Save us the cost of checking file size twice in LogAndApply
  uint64_t last_observed_manifest_size_;

-  // storage options for all reads and writes except compactions
-  const EnvOptions& storage_options_;
-
-  // storage options used for compactions. This is a copy of
-  // storage_options_ but with readaheads set to readahead_compactions_.
-  const EnvOptions storage_options_compactions_;
-
  // No copying allowed
  VersionSet(const VersionSet&);
  void operator=(const VersionSet&);
@@ -528,12 +479,9 @@ class Compaction {
  ~Compaction();

  // Return the level that is being compacted.  Inputs from "level"
-  // will be merged.
+  // and "level+1" will be merged to produce a set of "level+1" files.
  int level() const { return level_; }

-  // Outputs will go to this level
-  int output_level() const { return out_level_; }
-
  // Return the object that holds the edits to the descriptor done
  // by this compaction.
  VersionEdit* edit() { return edit_; }
@@ -572,21 +520,17 @@ class Compaction {
  // Return the score that was used to pick this compaction run.
  double score() const { return score_; }

-  // Is this compaction creating a file in the bottom most level?
-  bool BottomMostLevel() { return bottommost_level_; }
-
 private:
  friend class Version;
  friend class VersionSet;

-  explicit Compaction(int level, int out_level, uint64_t target_file_size,
+  explicit Compaction(int level, uint64_t target_file_size,
    uint64_t max_grandparent_overlap_bytes, int number_levels,
    bool seek_compaction = false);

  int level_;
-  int out_level_; // levels to which output files are stored
  uint64_t max_output_file_size_;
-  uint64_t maxGrandParentOverlapBytes_;
+  int64_t maxGrandParentOverlapBytes_;
  Version* input_version_;
  VersionEdit* edit_;
  int number_levels_;
@@ -601,32 +545,28 @@ class Compaction {
  std::vector<FileMetaData*> grandparents_;
  size_t grandparent_index_;  // Index in grandparent_starts_
  bool seen_key_;             // Some output key has been seen
-  uint64_t overlapped_bytes_;  // Bytes of overlap between current output
+  int64_t overlapped_bytes_;  // Bytes of overlap between current output
                              // and grandparent files
  int base_index_;   // index of the file in files_[level_]
  int parent_index_; // index of some file with same range in files_[level_+1]
  double score_;     // score that was used to pick this compaction.

-  // Is this compaction creating a file in the bottom most level?
-  bool bottommost_level_;
+  // State for implementing IsBaseLevelForKey

  // level_ptrs_ holds indices into input_version_->levels_: our state
  // is that we are positioned at one of the file ranges for each
  // higher level than the ones involved in this compaction (i.e. for
  // all L >= level_ + 2).
-  std::vector<size_t> level_ptrs_;
+  size_t* level_ptrs_;

  // mark (or clear) all files that are being compacted
  void MarkFilesBeingCompacted(bool);

-  // Initialize whether compaction producing files at the bottommost level
-  void SetupBottomMostLevel(bool isManual);
-
  // In case of compaction error, reset the nextIndex that is used
  // to pick up the next file to be compacted from files_by_size_
  void ResetNextCompactionIndex();
 };

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_DB_VERSION_SET_H_
@@ -10,7 +10,7 @@
 #include "db/log_writer.h"
 #include "util/logging.h"

-namespace rocksdb {
+namespace leveldb {

 Status VersionSet::ReduceNumberOfLevels(int new_levels, port::Mutex* mu) {

@@ -7,7 +7,7 @@
 #include "util/testharness.h"
 #include "util/testutil.h"

-namespace rocksdb {
+namespace leveldb {

 class FindFileTest {
 public:
@@ -172,8 +172,8 @@ TEST(FindFileTest, OverlappingFiles) {
  ASSERT_TRUE(Overlaps("600", "700"));
 }

-}  // namespace rocksdb
+}  // namespace leveldb

 int main(int argc, char** argv) {
-  return rocksdb::test::RunAllTests();
+  return leveldb::test::RunAllTests();
 }
@@ -7,26 +7,21 @@
 //    count: fixed32
 //    data: record[count]
 // record :=
-//    kTypeValue varstring varstring
-//    kTypeMerge varstring varstring
+//    kTypeValue varstring varstring         |
 //    kTypeDeletion varstring
 // varstring :=
 //    len: varint32
 //    data: uint8[len]

-#include "rocksdb/write_batch.h"
+#include "leveldb/write_batch.h"

-#include "rocksdb/options.h"
-#include "rocksdb/statistics.h"
+#include "leveldb/db.h"
 #include "db/dbformat.h"
-#include "db/db_impl.h"
 #include "db/memtable.h"
-#include "db/snapshot.h"
 #include "db/write_batch_internal.h"
 #include "util/coding.h"
-#include <stdexcept>

-namespace rocksdb {
+namespace leveldb {

 // WriteBatch header has an 8-byte sequence number followed by a 4-byte count.
 static const size_t kHeader = 12;
@@ -39,28 +34,11 @@ WriteBatch::~WriteBatch() { }

 WriteBatch::Handler::~Handler() { }

-void WriteBatch::Handler::Merge(const Slice& key, const Slice& value) {
-  throw std::runtime_error("Handler::Merge not implemented!");
-}
-
-void WriteBatch::Handler::LogData(const Slice& blob) {
-  // If the user has not specified something to do with blobs, then we ignore
-  // them.
-}
-
-bool WriteBatch::Handler::Continue() {
-  return true;
-}
-
 void WriteBatch::Clear() {
  rep_.clear();
  rep_.resize(kHeader);
 }

-int WriteBatch::Count() const {
-  return WriteBatchInternal::Count(this);
-}
-
 Status WriteBatch::Iterate(Handler* handler) const {
  Slice input(rep_);
  if (input.size() < kHeader) {
@@ -68,9 +46,10 @@ Status WriteBatch::Iterate(Handler* handler) const {
  }

  input.remove_prefix(kHeader);
-  Slice key, value, blob;
+  Slice key, value;
  int found = 0;
-  while (!input.empty() && handler->Continue()) {
+  while (!input.empty()) {
+    found++;
    char tag = input[0];
    input.remove_prefix(1);
    switch (tag) {
@@ -78,7 +57,6 @@ Status WriteBatch::Iterate(Handler* handler) const {
        if (GetLengthPrefixedSlice(&input, &key) &&
            GetLengthPrefixedSlice(&input, &value)) {
          handler->Put(key, value);
-          found++;
        } else {
          return Status::Corruption("bad WriteBatch Put");
        }
@@ -86,27 +64,10 @@ Status WriteBatch::Iterate(Handler* handler) const {
      case kTypeDeletion:
        if (GetLengthPrefixedSlice(&input, &key)) {
          handler->Delete(key);
-          found++;
        } else {
          return Status::Corruption("bad WriteBatch Delete");
        }
        break;
-      case kTypeMerge:
-        if (GetLengthPrefixedSlice(&input, &key) &&
-            GetLengthPrefixedSlice(&input, &value)) {
-          handler->Merge(key, value);
-          found++;
-        } else {
-          return Status::Corruption("bad WriteBatch Merge");
-        }
-        break;
-      case kTypeLogData:
-        if (GetLengthPrefixedSlice(&input, &blob)) {
-          handler->LogData(blob);
-        } else {
-          return Status::Corruption("bad WriteBatch Blob");
-        }
-        break;
      default:
        return Status::Corruption("unknown WriteBatch tag");
    }
@@ -147,72 +108,28 @@ void WriteBatch::Delete(const Slice& key) {
  PutLengthPrefixedSlice(&rep_, key);
 }

-void WriteBatch::Merge(const Slice& key, const Slice& value) {
-  WriteBatchInternal::SetCount(this, WriteBatchInternal::Count(this) + 1);
-  rep_.push_back(static_cast<char>(kTypeMerge));
-  PutLengthPrefixedSlice(&rep_, key);
-  PutLengthPrefixedSlice(&rep_, value);
-}
-
-void WriteBatch::PutLogData(const Slice& blob) {
-  rep_.push_back(static_cast<char>(kTypeLogData));
-  PutLengthPrefixedSlice(&rep_, blob);
-}
-
 namespace {
 class MemTableInserter : public WriteBatch::Handler {
 public:
  SequenceNumber sequence_;
  MemTable* mem_;
-  const Options* options_;
-  DBImpl* db_;
-  const bool filter_deletes_;
-
-  MemTableInserter(SequenceNumber sequence, MemTable* mem, const Options* opts,
-                   DB* db, const bool filter_deletes)
-    : sequence_(sequence),
-      mem_(mem),
-      options_(opts),
-      db_(reinterpret_cast<DBImpl*>(db)),
-      filter_deletes_(filter_deletes) {
-    assert(mem_);
-    if (filter_deletes_) {
-      assert(options_);
-      assert(db_);
-    }
-  }

  virtual void Put(const Slice& key, const Slice& value) {
    mem_->Add(sequence_, kTypeValue, key, value);
    sequence_++;
  }
-  virtual void Merge(const Slice& key, const Slice& value) {
-    mem_->Add(sequence_, kTypeMerge, key, value);
-    sequence_++;
-  }
  virtual void Delete(const Slice& key) {
-    if (filter_deletes_) {
-      SnapshotImpl read_from_snapshot;
-      read_from_snapshot.number_ = sequence_;
-      ReadOptions ropts;
-      ropts.snapshot = &read_from_snapshot;
-      std::string value;
-      if (!db_->KeyMayExist(ropts, key, &value)) {
-        RecordTick(options_->statistics, NUMBER_FILTERED_DELETES);
-        return;
-      }
-    }
    mem_->Add(sequence_, kTypeDeletion, key, Slice());
    sequence_++;
  }
 };
 }  // namespace

-Status WriteBatchInternal::InsertInto(const WriteBatch* b, MemTable* mem,
-                                      const Options* opts, DB* db,
-                                      const bool filter_deletes) {
-  MemTableInserter inserter(WriteBatchInternal::Sequence(b), mem, opts, db,
-                            filter_deletes);
+Status WriteBatchInternal::InsertInto(const WriteBatch* b,
+                                      MemTable* memtable) {
+  MemTableInserter inserter;
+  inserter.sequence_ = WriteBatchInternal::Sequence(b);
+  inserter.mem_ = memtable;
  return b->Iterate(&inserter);
 }

@@ -227,4 +144,4 @@ void WriteBatchInternal::Append(WriteBatch* dst, const WriteBatch* src) {
  dst->rep_.append(src->rep_.data() + kHeader, src->rep_.size() - kHeader);
 }

-}  // namespace rocksdb
+}  // namespace leveldb
@@ -5,12 +5,10 @@
 #ifndef STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_
 #define STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_

-#include "rocksdb/types.h"
-#include "rocksdb/write_batch.h"
-#include "rocksdb/db.h"
-#include "rocksdb/options.h"
+#include "leveldb/types.h"
+#include "leveldb/write_batch.h"

-namespace rocksdb {
+namespace leveldb {

 class MemTable;

@@ -41,17 +39,12 @@ class WriteBatchInternal {

  static void SetContents(WriteBatch* batch, const Slice& contents);

-  // Inserts batch entries into memtable
-  // Drops deletes in batch if filter_del is set to true and
-  // db->KeyMayExist returns false
-  static Status InsertInto(const WriteBatch* batch, MemTable* memtable,
-                           const Options* opts = nullptr, DB* db = nullptr,
-                           const bool filter_del = false);
+  static Status InsertInto(const WriteBatch* batch, MemTable* memtable);

  static void Append(WriteBatch* dst, const WriteBatch* src);
 };

-}  // namespace rocksdb
+}  // namespace leveldb


 #endif  // STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_
@@ -2,22 +2,19 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

-#include "rocksdb/db.h"
+#include "leveldb/db.h"

-#include <memory>
 #include "db/memtable.h"
 #include "db/write_batch_internal.h"
-#include "rocksdb/env.h"
-#include "rocksdb/memtablerep.h"
+#include "leveldb/env.h"
 #include "util/logging.h"
 #include "util/testharness.h"

-namespace rocksdb {
+namespace leveldb {

 static std::string PrintContents(WriteBatch* b) {
  InternalKeyComparator cmp(BytewiseComparator());
-  auto factory = std::make_shared<SkipListFactory>();
-  MemTable* mem = new MemTable(cmp, factory);
+  MemTable* mem = new MemTable(cmp);
  mem->Ref();
  std::string state;
  Status s = WriteBatchInternal::InsertInto(b, mem);
@@ -36,30 +33,19 @@ static std::string PrintContents(WriteBatch* b) {
        state.append(")");
        count++;
        break;
-      case kTypeMerge:
-        state.append("Merge(");
-        state.append(ikey.user_key.ToString());
-        state.append(", ");
-        state.append(iter->value().ToString());
-        state.append(")");
-        count++;
-        break;
      case kTypeDeletion:
        state.append("Delete(");
        state.append(ikey.user_key.ToString());
        state.append(")");
        count++;
        break;
-      case kTypeLogData:
-        assert(false);
-        break;
    }
    state.append("@");
    state.append(NumberToString(ikey.sequence));
  }
  delete iter;
  if (!s.ok()) {
-    state.append(s.ToString());
+    state.append("ParseError()");
  } else if (count != WriteBatchInternal::Count(b)) {
    state.append("CountMismatch()");
  }
@@ -73,7 +59,6 @@ TEST(WriteBatchTest, Empty) {
  WriteBatch batch;
  ASSERT_EQ("", PrintContents(&batch));
  ASSERT_EQ(0, WriteBatchInternal::Count(&batch));
-  ASSERT_EQ(0, batch.Count());
 }

 TEST(WriteBatchTest, Multiple) {
@@ -88,7 +73,6 @@ TEST(WriteBatchTest, Multiple) {
            "Delete(box)@101"
            "Put(foo, bar)@100",
            PrintContents(&batch));
-  ASSERT_EQ(3, batch.Count());
 }

 TEST(WriteBatchTest, Corruption) {
@@ -100,7 +84,7 @@ TEST(WriteBatchTest, Corruption) {
  WriteBatchInternal::SetContents(&batch,
                                  Slice(contents.data(),contents.size()-1));
  ASSERT_EQ("Put(foo, bar)@200"
-            "Corruption: bad WriteBatch Delete",
+            "ParseError()",
            PrintContents(&batch));
 }

@@ -111,19 +95,16 @@ TEST(WriteBatchTest, Append) {
  WriteBatchInternal::Append(&b1, &b2);
  ASSERT_EQ("",
            PrintContents(&b1));
-  ASSERT_EQ(0, b1.Count());
  b2.Put("a", "va");
  WriteBatchInternal::Append(&b1, &b2);
  ASSERT_EQ("Put(a, va)@200",
            PrintContents(&b1));
-  ASSERT_EQ(1, b1.Count());
  b2.Clear();
  b2.Put("b", "vb");
  WriteBatchInternal::Append(&b1, &b2);
  ASSERT_EQ("Put(a, va)@200"
            "Put(b, vb)@201",
            PrintContents(&b1));
-  ASSERT_EQ(2, b1.Count());
  b2.Delete("foo");
  WriteBatchInternal::Append(&b1, &b2);
  ASSERT_EQ("Put(a, va)@200"
@@ -131,98 +112,10 @@ TEST(WriteBatchTest, Append) {
            "Put(b, vb)@201"
            "Delete(foo)@203",
            PrintContents(&b1));
-  ASSERT_EQ(4, b1.Count());
 }

-namespace {
-  struct TestHandler : public WriteBatch::Handler {
-    std::string seen;
-    virtual void Put(const Slice& key, const Slice& value) {
-      seen += "Put(" + key.ToString() + ", " + value.ToString() + ")";
-    }
-    virtual void Merge(const Slice& key, const Slice& value) {
-      seen += "Merge(" + key.ToString() + ", " + value.ToString() + ")";
-    }
-    virtual void LogData(const Slice& blob) {
-      seen += "LogData(" + blob.ToString() + ")";
-    }
-    virtual void Delete(const Slice& key) {
-      seen += "Delete(" + key.ToString() + ")";
-    }
-  };
-}
-
-TEST(WriteBatchTest, Blob) {
-  WriteBatch batch;
-  batch.Put(Slice("k1"), Slice("v1"));
-  batch.Put(Slice("k2"), Slice("v2"));
-  batch.Put(Slice("k3"), Slice("v3"));
-  batch.PutLogData(Slice("blob1"));
-  batch.Delete(Slice("k2"));
-  batch.PutLogData(Slice("blob2"));
-  batch.Merge(Slice("foo"), Slice("bar"));
-  ASSERT_EQ(5, batch.Count());
-  ASSERT_EQ("Merge(foo, bar)@4"
-            "Put(k1, v1)@0"
-            "Delete(k2)@3"
-            "Put(k2, v2)@1"
-            "Put(k3, v3)@2",
-            PrintContents(&batch));
-
-  TestHandler handler;
-  batch.Iterate(&handler);
-  ASSERT_EQ(
-            "Put(k1, v1)"
-            "Put(k2, v2)"
-            "Put(k3, v3)"
-            "LogData(blob1)"
-            "Delete(k2)"
-            "LogData(blob2)"
-            "Merge(foo, bar)",
-            handler.seen);
-}
-
-TEST(WriteBatchTest, Continue) {
-  WriteBatch batch;
-
-  struct Handler : public TestHandler {
-    int num_seen = 0;
-    virtual void Put(const Slice& key, const Slice& value) {
-      ++num_seen;
-      TestHandler::Put(key, value);
-    }
-    virtual void Merge(const Slice& key, const Slice& value) {
-      ++num_seen;
-      TestHandler::Merge(key, value);
-    }
-    virtual void LogData(const Slice& blob) {
-      ++num_seen;
-      TestHandler::LogData(blob);
-    }
-    virtual void Delete(const Slice& key) {
-      ++num_seen;
-      TestHandler::Delete(key);
-    }
-    virtual bool Continue() override {
-      return num_seen < 3;
-    }
-  } handler;
-
-  batch.Put(Slice("k1"), Slice("v1"));
-  batch.PutLogData(Slice("blob1"));
-  batch.Delete(Slice("k1"));
-  batch.PutLogData(Slice("blob2"));
-  batch.Merge(Slice("foo"), Slice("bar"));
-  batch.Iterate(&handler);
-  ASSERT_EQ(
-            "Put(k1, v1)"
-            "LogData(blob1)"
-            "Delete(k1)",
-            handler.seen);
-}
-
-}  // namespace rocksdb
+}  // namespace leveldb

 int main(int argc, char** argv) {
-  return rocksdb::test::RunAllTests();
+  return leveldb::test::RunAllTests();
 }
@@ -111,7 +111,7 @@ static void WalCheckpoint(sqlite3* db_) {
  }
 }

-namespace rocksdb {
+namespace leveldb {

 // Helper for quickly generating random data.
 namespace {
@@ -664,7 +664,7 @@ class Benchmark {

 };

-}  // namespace rocksdb
+}  // namespace leveldb

 int main(int argc, char** argv) {
  std::string default_db_path;
@@ -672,7 +672,7 @@ int main(int argc, char** argv) {
    double d;
    int n;
    char junk;
-    if (rocksdb::Slice(argv[i]).starts_with("--benchmarks=")) {
+    if (leveldb::Slice(argv[i]).starts_with("--benchmarks=")) {
      FLAGS_benchmarks = argv[i] + strlen("--benchmarks=");
    } else if (sscanf(argv[i], "--histogram=%d%c", &n, &junk) == 1 &&
               (n == 0 || n == 1)) {
@@ -688,7 +688,7 @@ int main(int argc, char** argv) {
      FLAGS_reads = n;
    } else if (sscanf(argv[i], "--value_size=%d%c", &n, &junk) == 1) {
      FLAGS_value_size = n;
-    } else if (rocksdb::Slice(argv[i]) == rocksdb::Slice("--no_transaction")) {
+    } else if (leveldb::Slice(argv[i]) == leveldb::Slice("--no_transaction")) {
      FLAGS_transaction = false;
    } else if (sscanf(argv[i], "--page_size=%d%c", &n, &junk) == 1) {
      FLAGS_page_size = n;
@@ -707,12 +707,12 @@ int main(int argc, char** argv) {

  // Choose a location for the test database if none given with --db=<path>
  if (FLAGS_db == NULL) {
-      rocksdb::Env::Default()->GetTestDirectory(&default_db_path);
+      leveldb::Env::Default()->GetTestDirectory(&default_db_path);
      default_db_path += "/dbbench";
      FLAGS_db = default_db_path.c_str();
  }

-  rocksdb::Benchmark benchmark;
+  leveldb::Benchmark benchmark;
  benchmark.Run();
  return 0;
 }
@@ -80,7 +80,7 @@ static void DBSynchronize(kyotocabinet::TreeDB* db_)
  }
 }

-namespace rocksdb {
+namespace leveldb {

 // Helper for quickly generating random data.
 namespace {
@@ -479,7 +479,7 @@ class Benchmark {
  }
 };

-}  // namespace rocksdb
+}  // namespace leveldb

 int main(int argc, char** argv) {
  std::string default_db_path;
@@ -487,7 +487,7 @@ int main(int argc, char** argv) {
    double d;
    int n;
    char junk;
-    if (rocksdb::Slice(argv[i]).starts_with("--benchmarks=")) {
+    if (leveldb::Slice(argv[i]).starts_with("--benchmarks=")) {
      FLAGS_benchmarks = argv[i] + strlen("--benchmarks=");
    } else if (sscanf(argv[i], "--compression_ratio=%lf%c", &d, &junk) == 1) {
      FLAGS_compression_ratio = d;
@@ -517,12 +517,12 @@ int main(int argc, char** argv) {

  // Choose a location for the test database if none given with --db=<path>
  if (FLAGS_db == NULL) {
-      rocksdb::Env::Default()->GetTestDirectory(&default_db_path);
+      leveldb::Env::Default()->GetTestDirectory(&default_db_path);
      default_db_path += "/dbbench";
      FLAGS_db = default_db_path.c_str();
  }

-  rocksdb::Benchmark benchmark;
+  leveldb::Benchmark benchmark;
  benchmark.Run();
  return 0;
 }
@@ -25,27 +25,27 @@ creating it if necessary:
  #include &lt;assert&gt;
  #include "leveldb/db.h"

-  rocksdb::DB* db;
-  rocksdb::Options options;
+  leveldb::DB* db;
+  leveldb::Options options;
  options.create_if_missing = true;
-  rocksdb::Status status = rocksdb::DB::Open(options, "/tmp/testdb", &amp;db);
+  leveldb::Status status = leveldb::DB::Open(options, "/tmp/testdb", &amp;db);
  assert(status.ok());
  ...
 </pre>
 If you want to raise an error if the database already exists, add
-the following line before the <code>rocksdb::DB::Open</code> call:
+the following line before the <code>leveldb::DB::Open</code> call:
 <pre>
  options.error_if_exists = true;
 </pre>
 <h1>Status</h1>
 <p>
-You may have noticed the <code>rocksdb::Status</code> type above.  Values of this
+You may have noticed the <code>leveldb::Status</code> type above.  Values of this
 type are returned by most functions in <code>leveldb</code> that may encounter an
 error.  You can check if such a result is ok, and also print an
 associated error message:
 <p>
 <pre>
-   rocksdb::Status s = ...;
+   leveldb::Status s = ...;
   if (!s.ok()) cerr &lt;&lt; s.ToString() &lt;&lt; endl;
 </pre>
 <h1>Closing A Database</h1>
@@ -65,9 +65,9 @@ modify/query the database.  For example, the following code
 moves the value stored under key1 to key2.
 <pre>
  std::string value;
-  rocksdb::Status s = db-&gt;Get(rocksdb::ReadOptions(), key1, &amp;value);
-  if (s.ok()) s = db-&gt;Put(rocksdb::WriteOptions(), key2, value);
-  if (s.ok()) s = db-&gt;Delete(rocksdb::WriteOptions(), key1);
+  leveldb::Status s = db-&gt;Get(leveldb::ReadOptions(), key1, &amp;value);
+  if (s.ok()) s = db-&gt;Put(leveldb::WriteOptions(), key2, value);
+  if (s.ok()) s = db-&gt;Delete(leveldb::WriteOptions(), key1);
 </pre>

 <h1>Atomic Updates</h1>
@@ -81,12 +81,12 @@ atomically apply a set of updates:
  #include "leveldb/write_batch.h"
  ...
  std::string value;
-  rocksdb::Status s = db-&gt;Get(rocksdb::ReadOptions(), key1, &amp;value);
+  leveldb::Status s = db-&gt;Get(leveldb::ReadOptions(), key1, &amp;value);
  if (s.ok()) {
-    rocksdb::WriteBatch batch;
+    leveldb::WriteBatch batch;
    batch.Delete(key1);
    batch.Put(key2, value);
-    s = db-&gt;Write(rocksdb::WriteOptions(), &amp;batch);
+    s = db-&gt;Write(leveldb::WriteOptions(), &amp;batch);
  }
 </pre>
 The <code>WriteBatch</code> holds a sequence of edits to be made to the database,
@@ -109,7 +109,7 @@ persistent storage.  (On Posix systems, this is implemented by calling
 either <code>fsync(...)</code> or <code>fdatasync(...)</code> or
 <code>msync(..., MS_SYNC)</code> before the write operation returns.)
 <pre>
-  rocksdb::WriteOptions write_options;
+  leveldb::WriteOptions write_options;
  write_options.sync = true;
  db-&gt;Put(write_options, ...);
 </pre>
@@ -144,7 +144,7 @@ the batch.
 A database may only be opened by one process at a time.
 The <code>leveldb</code> implementation acquires a lock from the
 operating system to prevent misuse.  Within a single process, the
-same <code>rocksdb::DB</code> object may be safely shared by multiple
+same <code>leveldb::DB</code> object may be safely shared by multiple
 concurrent threads.  I.e., different threads may write into or fetch
 iterators or call <code>Get</code> on the same database without any
 external synchronization (the leveldb implementation will
@@ -160,7 +160,7 @@ The following example demonstrates how to print all key,value pairs
 in a database.
 <p>
 <pre>
-  rocksdb::Iterator* it = db-&gt;NewIterator(rocksdb::ReadOptions());
+  leveldb::Iterator* it = db-&gt;NewIterator(leveldb::ReadOptions());
  for (it-&gt;SeekToFirst(); it-&gt;Valid(); it-&gt;Next()) {
    cout &lt;&lt; it-&gt;key().ToString() &lt;&lt; ": "  &lt;&lt; it-&gt;value().ToString() &lt;&lt; endl;
  }
@@ -196,10 +196,10 @@ implicit snapshot of the current state.
 Snapshots are created by the DB::GetSnapshot() method:
 <p>
 <pre>
-  rocksdb::ReadOptions options;
+  leveldb::ReadOptions options;
  options.snapshot = db-&gt;GetSnapshot();
  ... apply some updates to db ...
-  rocksdb::Iterator* iter = db-&gt;NewIterator(options);
+  leveldb::Iterator* iter = db-&gt;NewIterator(options);
  ... read using iter to view the state when the snapshot was created ...
  delete iter;
  db-&gt;ReleaseSnapshot(options.snapshot);
@@ -211,7 +211,7 @@ support reading as of that snapshot.
 <h1>Slice</h1>
 <p>
 The return value of the <code>it->key()</code> and <code>it->value()</code> calls above
-are instances of the <code>rocksdb::Slice</code> type.  <code>Slice</code> is a simple
+are instances of the <code>leveldb::Slice</code> type.  <code>Slice</code> is a simple
 structure that contains a length and a pointer to an external byte
 array.  Returning a <code>Slice</code> is a cheaper alternative to returning a
 <code>std::string</code> since we do not need to copy potentially large keys and
@@ -223,10 +223,10 @@ C++ strings and null-terminated C-style strings can be easily converted
 to a Slice:
 <p>
 <pre>
-   rocksdb::Slice s1 = "hello";
+   leveldb::Slice s1 = "hello";

   std::string str("world");
-   rocksdb::Slice s2 = str;
+   leveldb::Slice s2 = str;
 </pre>
 A Slice can be easily converted back to a C++ string:
 <pre>
@@ -238,7 +238,7 @@ the external byte array into which the Slice points remains live while
 the Slice is in use.  For example, the following is buggy:
 <p>
 <pre>
-   rocksdb::Slice slice;
+   leveldb::Slice slice;
   if (...) {
     std::string str = ...;
     slice = str;
@@ -255,16 +255,16 @@ which orders bytes lexicographically.  You can however supply a custom
 comparator when opening a database.  For example, suppose each
 database key consists of two numbers and we should sort by the first
 number, breaking ties by the second number.  First, define a proper
-subclass of <code>rocksdb::Comparator</code> that expresses these rules:
+subclass of <code>leveldb::Comparator</code> that expresses these rules:
 <p>
 <pre>
-  class TwoPartComparator : public rocksdb::Comparator {
+  class TwoPartComparator : public leveldb::Comparator {
   public:
    // Three-way comparison function:
    //   if a &lt; b: negative result
    //   if a &gt; b: positive result
    //   else: zero result
-    int Compare(const rocksdb::Slice&amp; a, const rocksdb::Slice&amp; b) const {
+    int Compare(const leveldb::Slice&amp; a, const leveldb::Slice&amp; b) const {
      int a1, a2, b1, b2;
      ParseKey(a, &amp;a1, &amp;a2);
      ParseKey(b, &amp;b1, &amp;b2);
@@ -277,7 +277,7 @@ subclass of <code>rocksdb::Comparator</code> that expresses these rules:

    // Ignore the following methods for now:
    const char* Name() const { return "TwoPartComparator"; }
-    void FindShortestSeparator(std::string*, const rocksdb::Slice&amp;) const { }
+    void FindShortestSeparator(std::string*, const leveldb::Slice&amp;) const { }
    void FindShortSuccessor(std::string*) const { }
  };
 </pre>
@@ -285,18 +285,18 @@ Now create a database using this custom comparator:
 <p>
 <pre>
  TwoPartComparator cmp;
-  rocksdb::DB* db;
-  rocksdb::Options options;
+  leveldb::DB* db;
+  leveldb::Options options;
  options.create_if_missing = true;
  options.comparator = &amp;cmp;
-  rocksdb::Status status = rocksdb::DB::Open(options, "/tmp/testdb", &amp;db);
+  leveldb::Status status = leveldb::DB::Open(options, "/tmp/testdb", &amp;db);
  ...
 </pre>
 <h2>Backwards compatibility</h2>
 <p>
 The result of the comparator's <code>Name</code> method is attached to the
 database when it is created, and is checked on every subsequent
-database open.  If the name changes, the <code>rocksdb::DB::Open</code> call will
+database open.  If the name changes, the <code>leveldb::DB::Open</code> call will
 fail.  Therefore, change the name if and only if the new key format
 and comparison function are incompatible with existing databases, and
 it is ok to discard the contents of all existing databases.
@@ -339,9 +339,9 @@ compression entirely, but should only do so if benchmarks show a
 performance improvement:
 <p>
 <pre>
-  rocksdb::Options options;
-  options.compression = rocksdb::kNoCompression;
-  ... rocksdb::DB::Open(options, name, ...) ....
+  leveldb::Options options;
+  options.compression = leveldb::kNoCompression;
+  ... leveldb::DB::Open(options, name, ...) ....
 </pre>
 <h2>Cache</h2>
 <p>
@@ -353,10 +353,10 @@ uncompressed block contents.
 <pre>
  #include "leveldb/cache.h"

-  rocksdb::Options options;
-  options.cache = rocksdb::NewLRUCache(100 * 1048576);  // 100MB cache
-  rocksdb::DB* db;
-  rocksdb::DB::Open(options, name, &db);
+  leveldb::Options options;
+  options.cache = leveldb::NewLRUCache(100 * 1048576);  // 100MB cache
+  leveldb::DB* db;
+  leveldb::DB::Open(options, name, &db);
  ... use the db ...
  delete db
  delete options.cache;
@@ -373,9 +373,9 @@ displacing most of the cached contents.  A per-iterator option can be
 used to achieve this:
 <p>
 <pre>
-  rocksdb::ReadOptions options;
+  leveldb::ReadOptions options;
  options.fill_cache = false;
-  rocksdb::Iterator* it = db-&gt;NewIterator(options);
+  leveldb::Iterator* it = db-&gt;NewIterator(options);
  for (it-&gt;SeekToFirst(); it-&gt;Valid(); it-&gt;Next()) {
    ...
  }
@@ -407,10 +407,10 @@ a single <code>Get()</code> call may involve multiple reads from disk.
 The optional <code>FilterPolicy</code> mechanism can be used to reduce
 the number of disk reads substantially.
 <pre>
-   rocksdb::Options options;
+   leveldb::Options options;
   options.filter_policy = NewBloomFilter(10);
-   rocksdb::DB* db;
-   rocksdb::DB::Open(options, "/tmp/testdb", &amp;db);
+   leveldb::DB* db;
+   leveldb::DB::Open(options, "/tmp/testdb", &amp;db);
   ... use the database ...
   delete db;
   delete options.filter_policy;
@@ -434,7 +434,7 @@ consider a comparator that ignores trailing spaces when comparing keys.
 Instead, the application should provide a custom filter policy that
 also ignores trailing spaces.  For example:
 <pre>
-  class CustomFilterPolicy : public rocksdb::FilterPolicy {
+  class CustomFilterPolicy : public leveldb::FilterPolicy {
   private:
    FilterPolicy* builtin_policy_;
   public:
@@ -484,7 +484,7 @@ checksums are verified:
  parts of its persistent storage have been corrupted.
 <p>
  If a database is corrupted (perhaps it cannot be opened when
-  paranoid checking is turned on), the <code>rocksdb::RepairDB</code> function
+  paranoid checking is turned on), the <code>leveldb::RepairDB</code> function
  may be used to recover as much of the data as possible
 <p>
 </ul>
@@ -494,11 +494,11 @@ The <code>GetApproximateSizes</code> method can used to get the approximate
 number of bytes of file system space used by one or more key ranges.
 <p>
 <pre>
-   rocksdb::Range ranges[2];
-   ranges[0] = rocksdb::Range("a", "c");
-   ranges[1] = rocksdb::Range("x", "z");
+   leveldb::Range ranges[2];
+   ranges[0] = leveldb::Range("a", "c");
+   ranges[1] = leveldb::Range("x", "z");
   uint64_t sizes[2];
-   rocksdb::Status s = db-&gt;GetApproximateSizes(ranges, 2, sizes);
+   leveldb::Status s = db-&gt;GetApproximateSizes(ranges, 2, sizes);
 </pre>
 The preceding call will set <code>sizes[0]</code> to the approximate number of
 bytes of file system space used by the key range <code>[a..c)</code> and
@@ -508,21 +508,21 @@ bytes of file system space used by the key range <code>[a..c)</code> and
 <h1>Environment</h1>
 <p>
 All file operations (and other operating system calls) issued by the
-<code>leveldb</code> implementation are routed through a <code>rocksdb::Env</code> object.
+<code>leveldb</code> implementation are routed through a <code>leveldb::Env</code> object.
 Sophisticated clients may wish to provide their own <code>Env</code>
 implementation to get better control.  For example, an application may
 introduce artificial delays in the file IO paths to limit the impact
 of <code>leveldb</code> on other activities in the system.
 <p>
 <pre>
-  class SlowEnv : public rocksdb::Env {
+  class SlowEnv : public leveldb::Env {
    .. implementation of the Env interface ...
  };

  SlowEnv env;
-  rocksdb::Options options;
+  leveldb::Options options;
  options.env = &amp;env;
-  Status s = rocksdb::DB::Open(options, ...);
+  Status s = leveldb::DB::Open(options, ...);
 </pre>
 <h1>Porting</h1>
 <p>
@@ -531,7 +531,7 @@ specific implementations of the types/methods/functions exported by
 <code>leveldb/port/port.h</code>.  See <code>leveldb/port/port_example.h</code> for more
 details.
 <p>
-In addition, the new platform may need a new default <code>rocksdb::Env</code>
+In addition, the new platform may need a new default <code>leveldb::Env</code>
 implementation.  See <code>leveldb/util/env_posix.h</code> for an example.

 <h1>Other Information</h1>
@@ -4,10 +4,10 @@
 # fbcode settings.  It uses the latest g++ compiler and also
 # uses jemalloc

-TOOLCHAIN_REV=83eb773e262fa705eaebbf3de40db71d53fabf2e
+TOOLCHAIN_REV=3748fabb2c5e033009597bae1f9ef8bf4b218581
 TOOLCHAIN_EXECUTABLES="/mnt/gvfs/third-party/$TOOLCHAIN_REV/centos5.2-native"
 TOOLCHAIN_LIB_BASE="/mnt/gvfs/third-party/$TOOLCHAIN_REV/gcc-4.7.1-glibc-2.14.1"
-TOOL_JEMALLOC=jemalloc-3.3.1/2f45f3a
+TOOL_JEMALLOC=jemalloc-3.0.0/2f45f3a

 # location of libhdfs libraries
 if test "$USE_HDFS"; then
@@ -25,13 +25,13 @@
 #include <sys/time.h>
 #include <time.h>
 #include <iostream>
-#include "rocksdb/env.h"
-#include "rocksdb/status.h"
+#include "leveldb/env.h"
+#include "leveldb/status.h"

 #ifdef USE_HDFS
 #include "hdfs/hdfs.h"

-namespace rocksdb {
+namespace leveldb {

 static const std::string kProto = "hdfs://";
 static const std::string pathsep = "/";
@@ -107,9 +107,8 @@ class HdfsEnv : public Env {

  virtual Status NewLogger(const std::string& fname, Logger** result);

-  virtual void Schedule(void (*function)(void* arg), void* arg,
-                        Priority pri = LOW) {
-    posixEnv->Schedule(function, arg, pri);
+  virtual void Schedule( void (*function)(void* arg), void* arg) {
+    posixEnv->Schedule(function, arg);
  }

  virtual void StartThread(void (*function)(void* arg), void* arg) {
@@ -141,8 +140,8 @@ class HdfsEnv : public Env {
    return posixEnv->GetAbsolutePath(db_path, output_path);
  }

-  virtual void SetBackgroundThreads(int number, Priority pri = LOW) {
-    posixEnv->SetBackgroundThreads(number, pri);
+  virtual void SetBackgroundThreads(int number) {
+    posixEnv->SetBackgroundThreads(number);
  }

  virtual std::string TimeToString(uint64_t number) {
@@ -214,12 +213,12 @@ class HdfsEnv : public Env {
  }
 };

-}  // namespace rocksdb
+}  // namespace leveldb

 #else // USE_HDFS


-namespace rocksdb {
+namespace leveldb {

 static const Status notsup;

@@ -236,18 +235,15 @@ class HdfsEnv : public Env {
  }

  virtual Status NewSequentialFile(const std::string& fname,
-                                   unique_ptr<SequentialFile>* result,
-                                   const EnvOptions& options);
+                                   unique_ptr<SequentialFile>* result);

  virtual Status NewRandomAccessFile(const std::string& fname,
-                                     unique_ptr<RandomAccessFile>* result,
-                                     const EnvOptions& options) {
+                                     unique_ptr<RandomAccessFile>* result) {
    return notsup;
  }

  virtual Status NewWritableFile(const std::string& fname,
-                                 unique_ptr<WritableFile>* result,
-                                 const EnvOptions& options) {
+                                 unique_ptr<WritableFile>* result) {
    return notsup;
  }

@@ -280,8 +276,7 @@ class HdfsEnv : public Env {
  virtual Status NewLogger(const std::string& fname,
                           shared_ptr<Logger>* result){return notsup;}

-  virtual void Schedule(void (*function)(void* arg), void* arg,
-                        Priority pri = LOW) {}
+  virtual void Schedule( void (*function)(void* arg), void* arg) {}

  virtual void StartThread(void (*function)(void* arg), void* arg) {}

@@ -298,7 +293,7 @@ class HdfsEnv : public Env {
  virtual Status GetAbsolutePath(const std::string& db_path,
      std::string* outputpath) {return notsup;}

-  virtual void SetBackgroundThreads(int number, Priority pri = LOW) {}
+  virtual void SetBackgroundThreads(int number) {}

  virtual std::string TimeToString(uint64_t number) { return "";}
 };
@@ -4,8 +4,8 @@

 #include "helpers/memenv/memenv.h"

-#include "rocksdb/env.h"
-#include "rocksdb/status.h"
+#include "leveldb/env.h"
+#include "leveldb/status.h"
 #include "port/port.h"
 #include "util/mutexlock.h"
 #include <map>
@@ -13,7 +13,7 @@
 #include <string>
 #include <vector>

-namespace rocksdb {
+namespace leveldb {

 namespace {

@@ -233,8 +233,7 @@ class InMemoryEnv : public EnvWrapper {

  // Partial implementation of the Env interface.
  virtual Status NewSequentialFile(const std::string& fname,
-                                   unique_ptr<SequentialFile>* result,
-                                   const EnvOptions& soptions) {
+                                   unique_ptr<SequentialFile>* result) {
    MutexLock lock(&mutex_);
    if (file_map_.find(fname) == file_map_.end()) {
      *result = NULL;
@@ -246,8 +245,7 @@ class InMemoryEnv : public EnvWrapper {
  }

  virtual Status NewRandomAccessFile(const std::string& fname,
-                                     unique_ptr<RandomAccessFile>* result,
-                                     const EnvOptions& soptions) {
+                                     unique_ptr<RandomAccessFile>* result) {
    MutexLock lock(&mutex_);
    if (file_map_.find(fname) == file_map_.end()) {
      *result = NULL;
@@ -259,8 +257,7 @@ class InMemoryEnv : public EnvWrapper {
  }

  virtual Status NewWritableFile(const std::string& fname,
-                                 unique_ptr<WritableFile>* result,
-                                 const EnvOptions& soptions) {
+                                 unique_ptr<WritableFile>* result) {
    MutexLock lock(&mutex_);
    if (file_map_.find(fname) != file_map_.end()) {
      DeleteFileInternal(fname);
@@ -383,4 +380,4 @@ Env* NewMemEnv(Env* base_env) {
  return new InMemoryEnv(base_env);
 }

-}  // namespace rocksdb
+}  // namespace leveldb
@@ -2,9 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

-#ifndef STORAGE_ROCKSDB_HELPERS_MEMENV_MEMENV_H_
-#define STORAGE_ROCKSDB_HELPERS_MEMENV_MEMENV_H_
-namespace rocksdb {
+#ifndef STORAGE_LEVELDB_HELPERS_MEMENV_MEMENV_H_
+#define STORAGE_LEVELDB_HELPERS_MEMENV_MEMENV_H_
+
+namespace leveldb {

 class Env;

@@ -14,6 +15,6 @@ class Env;
 // *base_env must remain live while the result is in use.
 Env* NewMemEnv(Env* base_env);

-}  // namespace rocksdb
+}  // namespace leveldb

-#endif  // STORAGE_ROCKSDB_HELPERS_MEMENV_MEMENV_H_
+#endif  // STORAGE_LEVELDB_HELPERS_MEMENV_MEMENV_H_
@@ -5,19 +5,18 @@
 #include "helpers/memenv/memenv.h"

 #include "db/db_impl.h"
-#include "rocksdb/db.h"
-#include "rocksdb/env.h"
+#include "leveldb/db.h"
+#include "leveldb/env.h"
 #include "util/testharness.h"
 #include <memory>
 #include <string>
 #include <vector>

-namespace rocksdb {
+namespace leveldb {

 class MemEnvTest {
 public:
  Env* env_;
-  const EnvOptions soptions_;

  MemEnvTest()
      : env_(NewMemEnv(Env::Default())) {
@@ -41,7 +40,7 @@ TEST(MemEnvTest, Basics) {
  ASSERT_EQ(0U, children.size());

  // Create a file.
-  ASSERT_OK(env_->NewWritableFile("/dir/f", &writable_file, soptions_));
+  ASSERT_OK(env_->NewWritableFile("/dir/f", &writable_file));
  writable_file.reset();

  // Check that the file exists.
@@ -53,7 +52,7 @@ TEST(MemEnvTest, Basics) {
  ASSERT_EQ("f", children[0]);

  // Write to the file.
-  ASSERT_OK(env_->NewWritableFile("/dir/f", &writable_file, soptions_));
+  ASSERT_OK(env_->NewWritableFile("/dir/f", &writable_file));
  ASSERT_OK(writable_file->Append("abc"));
  writable_file.reset();

@@ -72,11 +71,9 @@ TEST(MemEnvTest, Basics) {
  // Check that opening non-existent file fails.
  unique_ptr<SequentialFile> seq_file;
  unique_ptr<RandomAccessFile> rand_file;
-  ASSERT_TRUE(!env_->NewSequentialFile("/dir/non_existent", &seq_file,
-                                       soptions_).ok());
+  ASSERT_TRUE(!env_->NewSequentialFile("/dir/non_existent", &seq_file).ok());
  ASSERT_TRUE(!seq_file);
-  ASSERT_TRUE(!env_->NewRandomAccessFile("/dir/non_existent", &rand_file,
-                                         soptions_).ok());
+  ASSERT_TRUE(!env_->NewRandomAccessFile("/dir/non_existent", &rand_file).ok());
  ASSERT_TRUE(!rand_file);

  // Check that deleting works.
@@ -97,13 +94,13 @@ TEST(MemEnvTest, ReadWrite) {

  ASSERT_OK(env_->CreateDir("/dir"));

-  ASSERT_OK(env_->NewWritableFile("/dir/f", &writable_file, soptions_));
+  ASSERT_OK(env_->NewWritableFile("/dir/f", &writable_file));
  ASSERT_OK(writable_file->Append("hello "));
  ASSERT_OK(writable_file->Append("world"));
  writable_file.reset();

  // Read sequentially.
-  ASSERT_OK(env_->NewSequentialFile("/dir/f", &seq_file, soptions_));
+  ASSERT_OK(env_->NewSequentialFile("/dir/f", &seq_file));
  ASSERT_OK(seq_file->Read(5, &result, scratch)); // Read "hello".
  ASSERT_EQ(0, result.compare("hello"));
  ASSERT_OK(seq_file->Skip(1));
@@ -116,7 +113,7 @@ TEST(MemEnvTest, ReadWrite) {
  ASSERT_EQ(0U, result.size());

  // Random reads.
-  ASSERT_OK(env_->NewRandomAccessFile("/dir/f", &rand_file, soptions_));
+  ASSERT_OK(env_->NewRandomAccessFile("/dir/f", &rand_file));
  ASSERT_OK(rand_file->Read(6, 5, &result, scratch)); // Read "world".
  ASSERT_EQ(0, result.compare("world"));
  ASSERT_OK(rand_file->Read(0, 5, &result, scratch)); // Read "hello".
@@ -142,7 +139,7 @@ TEST(MemEnvTest, Misc) {
  ASSERT_TRUE(!test_dir.empty());

  unique_ptr<WritableFile> writable_file;
-  ASSERT_OK(env_->NewWritableFile("/a/b", &writable_file, soptions_));
+  ASSERT_OK(env_->NewWritableFile("/a/b", &writable_file));

  // These are no-ops, but we test they return success.
  ASSERT_OK(writable_file->Sync());
@@ -161,14 +158,14 @@ TEST(MemEnvTest, LargeWrite) {
  }

  unique_ptr<WritableFile> writable_file;
-  ASSERT_OK(env_->NewWritableFile("/dir/f", &writable_file, soptions_));
+  ASSERT_OK(env_->NewWritableFile("/dir/f", &writable_file));
  ASSERT_OK(writable_file->Append("foo"));
  ASSERT_OK(writable_file->Append(write_data));
  writable_file.reset();

  unique_ptr<SequentialFile> seq_file;
  Slice result;
-  ASSERT_OK(env_->NewSequentialFile("/dir/f", &seq_file, soptions_));
+  ASSERT_OK(env_->NewSequentialFile("/dir/f", &seq_file));
  ASSERT_OK(seq_file->Read(3, &result, scratch)); // Read "foo".
  ASSERT_EQ(0, result.compare("foo"));

@@ -226,8 +223,8 @@ TEST(MemEnvTest, DBTest) {
  delete db;
 }

-}  // namespace rocksdb
+}  // namespace leveldb

 int main(int argc, char** argv) {
-  return rocksdb::test::RunAllTests();
+  return leveldb::test::RunAllTests();
 }
@@ -37,8 +37,8 @@
  (5) All of the pointer arguments must be non-NULL.
 */

-#ifndef STORAGE_ROCKSDB_INCLUDE_C_H_
-#define STORAGE_ROCKSDB_INCLUDE_C_H_
+#ifndef STORAGE_LEVELDB_INCLUDE_C_H_
+#define STORAGE_LEVELDB_INCLUDE_C_H_

 #ifdef __cplusplus
 extern "C" {
@@ -278,4 +278,4 @@ extern void leveldb_env_destroy(leveldb_env_t*);
 }  /* end extern "C" */
 #endif

-#endif  /* STORAGE_ROCKSDB_INCLUDE_C_H_ */
+#endif  /* STORAGE_LEVELDB_INCLUDE_C_H_ */
@@ -15,14 +15,14 @@
 // they want something more sophisticated (like scan-resistance, a
 // custom eviction policy, variable cache sizing, etc.)

-#ifndef STORAGE_ROCKSDB_INCLUDE_CACHE_H_
-#define STORAGE_ROCKSDB_INCLUDE_CACHE_H_
+#ifndef STORAGE_LEVELDB_INCLUDE_CACHE_H_
+#define STORAGE_LEVELDB_INCLUDE_CACHE_H_

 #include <memory>
 #include <stdint.h>
-#include "rocksdb/slice.h"
+#include "leveldb/slice.h"

-namespace rocksdb {
+namespace leveldb {

 using std::shared_ptr;

@@ -101,8 +101,6 @@ class Cache {
  void operator=(const Cache&);
 };

-}  // namespace rocksdb
+}  // namespace leveldb

-#include "rocksdb/rocksdb_to_leveldb.h"
-
-#endif  // STORAGE_ROCKSDB_UTIL_CACHE_H_
+#endif  // STORAGE_LEVELDB_UTIL_CACHE_H_
@@ -2,12 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

-#ifndef STORAGE_ROCKSDB_INCLUDE_COMPARATOR_H_
-#define STORAGE_ROCKSDB_INCLUDE_COMPARATOR_H_
+#ifndef STORAGE_LEVELDB_INCLUDE_COMPARATOR_H_
+#define STORAGE_LEVELDB_INCLUDE_COMPARATOR_H_

 #include <string>

-namespace rocksdb {
+namespace leveldb {

 class Slice;

@@ -58,8 +58,6 @@ class Comparator {
 // must not be deleted.
 extern const Comparator* BytewiseComparator();

-}  // namespace rocksdb
+}  // namespace leveldb

-#include "rocksdb/rocksdb_to_leveldb.h"
-
-#endif  // STORAGE_ROCKSDB_INCLUDE_COMPARATOR_H_
+#endif  // STORAGE_LEVELDB_INCLUDE_COMPARATOR_H_
@@ -2,25 +2,25 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

-#ifndef STORAGE_ROCKSDB_INCLUDE_DB_H_
-#define STORAGE_ROCKSDB_INCLUDE_DB_H_
+#ifndef STORAGE_LEVELDB_INCLUDE_DB_H_
+#define STORAGE_LEVELDB_INCLUDE_DB_H_

 #include <stdint.h>
 #include <stdio.h>
 #include <memory>
 #include <vector>
-#include "rocksdb/iterator.h"
-#include "rocksdb/options.h"
-#include "rocksdb/types.h"
-#include "rocksdb/transaction_log.h"
+#include "leveldb/iterator.h"
+#include "leveldb/options.h"
+#include "leveldb/types.h"
+#include "leveldb/transaction_log_iterator.h"

-namespace rocksdb {
+namespace leveldb {

 using std::unique_ptr;

 // Update Makefile if you change these
-static const int kMajorVersion = 2;
-static const int kMinorVersion = 0;
+static const int kMajorVersion = 1;
+static const int kMinorVersion = 5;

 struct Options;
 struct ReadOptions;
@@ -28,17 +28,6 @@ struct WriteOptions;
 struct FlushOptions;
 class WriteBatch;

-// Metadata associated with each SST file.
-struct LiveFileMetaData {
-  std::string name;        // Name of the file
-  int level;               // Level at which this file resides.
-  size_t size;             // File size in bytes.
-  std::string smallestkey; // Smallest user defined key in the file.
-  std::string largestkey;  // Largest user defined key in the file.
-  SequenceNumber smallest_seqno; // smallest seqno in file
-  SequenceNumber largest_seqno;  // largest seqno in file
-};
-
 // Abstract handle to particular state of a DB.
 // A Snapshot is an immutable object and can therefore be safely
 // accessed from multiple threads without any external synchronization.
@@ -94,14 +83,6 @@ class DB {
  // Note: consider setting options.sync = true.
  virtual Status Delete(const WriteOptions& options, const Slice& key) = 0;

-  // Merge the database entry for "key" with "value".  Returns OK on success,
-  // and a non-OK status on error. The semantics of this operation is
-  // determined by the user provided merge_operator when opening DB.
-  // Note: consider setting options.sync = true.
-  virtual Status Merge(const WriteOptions& options,
-                       const Slice& key,
-                       const Slice& value) = 0;
-
  // Apply the specified updates to the database.
  // Returns OK on success, non-OK on failure.
  // Note: consider setting options.sync = true.
@@ -115,39 +96,7 @@ class DB {
  //
  // May return some other Status on an error.
  virtual Status Get(const ReadOptions& options,
-                     const Slice& key,
-                     std::string* value) = 0;
-
-  // If keys[i] does not exist in the database, then the i'th returned
-  // status will be one for which Status::IsNotFound() is true, and
-  // (*values)[i] will be set to some arbitrary value (often ""). Otherwise,
-  // the i'th returned status will have Status::ok() true, and (*values)[i]
-  // will store the value associated with keys[i].
-  //
-  // (*values) will always be resized to be the same size as (keys).
-  // Similarly, the number of returned statuses will be the number of keys.
-  // Note: keys will not be "de-duplicated". Duplicate keys will return
-  // duplicate values in order.
-  virtual std::vector<Status> MultiGet(const ReadOptions& options,
-                                       const std::vector<Slice>& keys,
-                                       std::vector<std::string>* values) = 0;
-
-  // If the key definitely does not exist in the database, then this method
-  // returns false, else true. If the caller wants to obtain value when the key
-  // is found in memory, a bool for 'value_found' must be passed. 'value_found'
-  // will be true on return if value has been set properly.
-  // This check is potentially lighter-weight than invoking DB::Get(). One way
-  // to make this lighter weight is to avoid doing any IOs.
-  // Default implementation here returns true and sets 'value_found' to false
-  virtual bool KeyMayExist(const ReadOptions& options,
-                           const Slice& key,
-                           std::string* value,
-                           bool* value_found = nullptr) {
-    if (value_found != nullptr) {
-      *value_found = false;
-    }
-    return true;
-  }
+                     const Slice& key, std::string* value) = 0;

  // Return a heap-allocated iterator over the contents of the database.
  // The result of NewIterator() is initially invalid (caller must
@@ -204,15 +153,7 @@ class DB {
  // end==nullptr is treated as a key after all keys in the database.
  // Therefore the following call will compact the entire database:
  //    db->CompactRange(nullptr, nullptr);
-  // Note that after the entire database is compacted, all data are pushed
-  // down to the last level containing any data. If the total data size
-  // after compaction is reduced, that level might not be appropriate for
-  // hosting all the files. In this case, client could set reduce_level
-  // to true, to move the files back to the minimum level capable of holding
-  // the data set or a given level (specified by non-negative target_level).
-  virtual void CompactRange(const Slice* begin, const Slice* end,
-                            bool reduce_level = false,
-                            int target_level = -1) = 0;
+  virtual void CompactRange(const Slice* begin, const Slice* end) = 0;

  // Number of levels used for this DB.
  virtual int NumberLevels() = 0;
@@ -235,33 +176,16 @@ class DB {
  // Allow compactions to delete obselete files.
  virtual Status EnableFileDeletions() = 0;

-  // GetLiveFiles followed by GetSortedWalFiles can generate a lossless backup
-
-  // THIS METHOD IS DEPRECATED. Use the GetTableMetaData to get more
-  // detailed information on the live files.
  // Retrieve the list of all files in the database. The files are
-  // relative to the dbname and are not absolute paths. The valid size of the
-  // manifest file is returned in manifest_file_size. The manifest file is an
-  // ever growing file, but only the portion specified by manifest_file_size is
-  // valid for this snapshot.
-  // Setting flush_memtable to true does Flush before recording the live files.
-  // Setting flush_memtable to false is useful when we don't want to wait for
-  // flush which may have to wait for compaction to complete taking an
-  // indeterminate time. But this will have to use GetSortedWalFiles after
-  // GetLiveFiles to compensate for memtables missed in this snapshot due to the
-  // absence of Flush, by WAL files to recover the database consistently later
+  // relative to the dbname and are not absolute paths. This list
+  // can be used to generate a backup. The valid size of the manifest
+  // file is returned in manifest_file_size. The manifest file is
+  // an ever growing file, but only the portion specified
+  // by manifest_file_size is valid for this snapshot.
  virtual Status GetLiveFiles(std::vector<std::string>&,
-                              uint64_t* manifest_file_size,
-                              bool flush_memtable = true) = 0;
+                              uint64_t* manifest_file_size) = 0;

-  // Retrieve the sorted list of all wal files with earliest file first
-  virtual Status GetSortedWalFiles(VectorLogPtr& files) = 0;
-
-  // Delete wal files in files. These can be either live or archived.
-  // Returns Status::OK if all files could be deleted, otherwise Status::IOError
-  virtual Status DeleteWalFiles(const VectorLogPtr& files) = 0;
-
-  // The sequence number of the most recent transaction.
+  // The sequence number of the most recent transaction. 
  virtual SequenceNumber GetLatestSequenceNumber() = 0;

  // Return's an iterator for all writes since the sequence number
@@ -277,19 +201,6 @@ class DB {
  // an update is read.
  virtual Status GetUpdatesSince(SequenceNumber seq_number,
                                 unique_ptr<TransactionLogIterator>* iter) = 0;
-
-  // Delete the file name from the db directory and update the internal
-  // state to reflect that.
-  virtual Status DeleteFile(std::string name) {
-    return Status::OK();
-  }
-
-  // Returns a list of all table files with their level, start key
-  // and end key
-  virtual void GetLiveFilesMetaData(
-    std::vector<LiveFileMetaData> *metadata) {
-  }
-
 private:
  // No copying allowed
  DB(const DB&);
@@ -306,8 +217,6 @@ Status DestroyDB(const std::string& name, const Options& options);
 // on a database that contains important information.
 Status RepairDB(const std::string& dbname, const Options& options);

-}  // namespace rocksdb
+}  // namespace leveldb

-#include "rocksdb/rocksdb_to_leveldb.h"
-
-#endif  // STORAGE_ROCKSDB_INCLUDE_DB_H_
+#endif  // STORAGE_LEVELDB_INCLUDE_DB_H_
@@ -10,17 +10,17 @@
 // All Env implementations are safe for concurrent access from
 // multiple threads without any external synchronization.

-#ifndef STORAGE_ROCKSDB_INCLUDE_ENV_H_
-#define STORAGE_ROCKSDB_INCLUDE_ENV_H_
+#ifndef STORAGE_LEVELDB_INCLUDE_ENV_H_
+#define STORAGE_LEVELDB_INCLUDE_ENV_H_

 #include <cstdarg>
 #include <string>
 #include <memory>
 #include <vector>
 #include <stdint.h>
-#include "rocksdb/status.h"
+#include "leveldb/status.h"

-namespace rocksdb {
+namespace leveldb {

 class FileLock;
 class Logger;
@@ -28,41 +28,10 @@ class RandomAccessFile;
 class SequentialFile;
 class Slice;
 class WritableFile;
-class Options;

 using std::unique_ptr;
 using std::shared_ptr;

-
-// Options while opening a file to read/write
-struct EnvOptions {
-
-  // construct with default Options
-  EnvOptions();
-
-  // construct from Options
-  explicit EnvOptions(const Options& options);
-
-  // If true, then allow caching of data in environment buffers
-  bool use_os_buffer;
-
-   // If true, then use mmap to read data
-  bool use_mmap_reads;
-
-   // If true, then use mmap to write data
-  bool use_mmap_writes;
-
-  // If true, set the FD_CLOEXEC on open fd.
-  bool set_fd_cloexec;
-
-  // Allows OS to incrementally sync files to disk while they are being
-  // written, in the background. Issue one request for every bytes_per_sync
-  // written. 0 turns it off.
-  // Default: 0
-  uint64_t bytes_per_sync;
-
-};
-
 class Env {
 public:
  Env() { }
@@ -82,9 +51,7 @@ class Env {
  //
  // The returned file will only be accessed by one thread at a time.
  virtual Status NewSequentialFile(const std::string& fname,
-                                   unique_ptr<SequentialFile>* result,
-                                   const EnvOptions& options)
-                                   = 0;
+                                   unique_ptr<SequentialFile>* result) = 0;

  // Create a brand new random access read-only file with the
  // specified name.  On success, stores a pointer to the new file in
@@ -94,9 +61,7 @@ class Env {
  //
  // The returned file may be concurrently accessed by multiple threads.
  virtual Status NewRandomAccessFile(const std::string& fname,
-                                     unique_ptr<RandomAccessFile>* result,
-                                     const EnvOptions& options)
-                                     = 0;
+                                     unique_ptr<RandomAccessFile>* result) = 0;

  // Create an object that writes to a new file with the specified
  // name.  Deletes any existing file with the same name and creates a
@@ -106,8 +71,7 @@ class Env {
  //
  // The returned file will only be accessed by one thread at a time.
  virtual Status NewWritableFile(const std::string& fname,
-                                 unique_ptr<WritableFile>* result,
-                                 const EnvOptions& options) = 0;
+                                 unique_ptr<WritableFile>* result) = 0;

  // Returns true iff the named file exists.
  virtual bool FileExists(const std::string& fname) = 0;
@@ -162,20 +126,15 @@ class Env {
  // REQUIRES: lock has not already been unlocked.
  virtual Status UnlockFile(FileLock* lock) = 0;

-  enum Priority { LOW, HIGH, TOTAL };
-
-  // Arrange to run "(*function)(arg)" once in a background thread, in
-  // the thread pool specified by pri. By default, jobs go to the 'LOW'
-  // priority thread pool.
-
+  // Arrange to run "(*function)(arg)" once in a background thread.
+  //
  // "function" may run in an unspecified thread.  Multiple functions
  // added to the same Env may run concurrently in different threads.
  // I.e., the caller may not assume that background work items are
  // serialized.
  virtual void Schedule(
      void (*function)(void* arg),
-      void* arg,
-      Priority pri = LOW) = 0;
+      void* arg) = 0;

  // Start a new thread, invoking "function(arg)" within the new thread.
  // When "function(arg)" returns, the thread will be destroyed.
@@ -195,13 +154,6 @@ class Env {
  // useful for computing deltas of time.
  virtual uint64_t NowMicros() = 0;

-  // Returns the number of nano-seconds since some fixed point in time. Only
-  // useful for computing deltas of time in one run.
-  // Default implementation simply relies on NowMicros
-  virtual uint64_t NowNanos() {
-    return NowMicros() * 1000;
-  }
-
  // Sleep/delay the thread for the perscribed number of micro-seconds.
  virtual void SleepForMicroseconds(int micros) = 0;

@@ -215,10 +167,9 @@ class Env {
  virtual Status GetAbsolutePath(const std::string& db_path,
      std::string* output_path) = 0;

-  // The number of background worker threads of a specific thread pool
-  // for this environment. 'LOW' is the default pool.
-  // default number: 1
-  virtual void SetBackgroundThreads(int number, Priority pri = LOW) = 0;
+  // The number of background worker threads for this environment.
+  // default: 1
+  virtual void SetBackgroundThreads(int number) = 0;

  // Converts seconds-since-Jan-01-1970 to a printable string
  virtual std::string TimeToString(uint64_t time) = 0;
@@ -253,13 +204,6 @@ class SequentialFile {
  //
  // REQUIRES: External synchronization
  virtual Status Skip(uint64_t n) = 0;
-
-  // Remove any kind of caching of data from the offset to offset+length
-  // of this file. If the length is 0, then it refers to the end of file.
-  // If the system is not caching the file contents, then this is a noop.
-  virtual Status InvalidateCache(size_t offset, size_t length) {
-    return Status::NotSupported("InvalidateCache not supported.");
-  }
 };

 // A file abstraction for randomly reading the contents of a file.
@@ -284,7 +228,7 @@ class RandomAccessFile {
  // the file is opened (and will stay the same while the file is open).
  // Furthermore, it tries to make this ID at most "max_size" bytes. If such an
  // ID can be created this function returns the length of the ID and places it
-  // in "id"; otherwise, this function returns 0, in which case "id"
+  // in "id"; otherwise, this function returns 0, in which case "id" may more
  // may not have been modified.
  //
  // This function guarantees, for IDs from a given environment, two unique ids
@@ -299,18 +243,6 @@ class RandomAccessFile {
    return 0; // Default implementation to prevent issues with backwards
              // compatibility.
  };
-
-
-  enum AccessPattern { NORMAL, RANDOM, SEQUENTIAL, WILLNEED, DONTNEED };
-
-  virtual void Hint(AccessPattern pattern) {}
-
-  // Remove any kind of caching of data from the offset to offset+length
-  // of this file. If the length is 0, then it refers to the end of file.
-  // If the system is not caching the file contents, then this is a noop.
-  virtual Status InvalidateCache(size_t offset, size_t length) {
-    return Status::NotSupported("InvalidateCache not supported.");
-  }
 };

 // A file abstraction for sequential writing.  The implementation
@@ -360,14 +292,6 @@ class WritableFile {
    *block_size = preallocation_block_size_;
  }

-  // Remove any kind of caching of data from the offset to offset+length
-  // of this file. If the length is 0, then it refers to the end of file.
-  // If the system is not caching the file contents, then this is a noop.
-  // This call has no effect on dirty pages in the cache.
-  virtual Status InvalidateCache(size_t offset, size_t length) {
-    return Status::NotSupported("InvalidateCache not supported.");
-  }
-
 protected:
  // PrepareWrite performs any necessary preparation for a write
  // before the write actually occurs.  This allows for pre-allocation
@@ -400,16 +324,6 @@ class WritableFile {
    return Status::OK();
  }

-  // Sync a file range with disk.
-  // offset is the starting byte of the file range to be synchronized.
-  // nbytes specifies the length of the range to be synchronized.
-  // This asks the OS to initiate flushing the cached data to disk,
-  // without waiting for completion.
-  // Default implementation does nothing.
-  virtual Status RangeSync(off64_t offset, off64_t nbytes) {
-    return Status::OK();
-  }
-
 private:
  size_t last_preallocated_block_;
  size_t preallocation_block_size_;
@@ -484,18 +398,15 @@ class EnvWrapper : public Env {

  // The following text is boilerplate that forwards all methods to target()
  Status NewSequentialFile(const std::string& f,
-                           unique_ptr<SequentialFile>* r,
-                           const EnvOptions& options) {
-    return target_->NewSequentialFile(f, r, options);
+                           unique_ptr<SequentialFile>* r) {
+    return target_->NewSequentialFile(f, r);
  }
  Status NewRandomAccessFile(const std::string& f,
-                             unique_ptr<RandomAccessFile>* r,
-                             const EnvOptions& options) {
-    return target_->NewRandomAccessFile(f, r, options);
+                             unique_ptr<RandomAccessFile>* r) {
+    return target_->NewRandomAccessFile(f, r);
  }
-  Status NewWritableFile(const std::string& f, unique_ptr<WritableFile>* r,
-                         const EnvOptions& options) {
-    return target_->NewWritableFile(f, r, options);
+  Status NewWritableFile(const std::string& f, unique_ptr<WritableFile>* r) {
+    return target_->NewWritableFile(f, r);
  }
  bool FileExists(const std::string& f) { return target_->FileExists(f); }
  Status GetChildren(const std::string& dir, std::vector<std::string>* r) {
@@ -523,8 +434,8 @@ class EnvWrapper : public Env {
    return target_->LockFile(f, l);
  }
  Status UnlockFile(FileLock* l) { return target_->UnlockFile(l); }
-  void Schedule(void (*f)(void*), void* a, Priority pri) {
-    return target_->Schedule(f, a, pri);
+  void Schedule(void (*f)(void*), void* a) {
+    return target_->Schedule(f, a);
  }
  void StartThread(void (*f)(void*), void* a) {
    return target_->StartThread(f, a);
@@ -552,8 +463,8 @@ class EnvWrapper : public Env {
      std::string* output_path) {
    return target_->GetAbsolutePath(db_path, output_path);
  }
-  void SetBackgroundThreads(int num, Priority pri) {
-    return target_->SetBackgroundThreads(num, pri);
+  void SetBackgroundThreads(int num) {
+    return target_->SetBackgroundThreads(num);
  }
  std::string TimeToString(uint64_t time) {
    return target_->TimeToString(time);
@@ -563,8 +474,6 @@ class EnvWrapper : public Env {
  Env* target_;
 };

-}  // namespace rocksdb
+}  // namespace leveldb

-#include "rocksdb/rocksdb_to_leveldb.h"
-
-#endif  // STORAGE_ROCKSDB_INCLUDE_ENV_H_
+#endif  // STORAGE_LEVELDB_INCLUDE_ENV_H_
@@ -13,12 +13,12 @@
 // Most people will want to use the builtin bloom filter support (see
 // NewBloomFilterPolicy() below).

-#ifndef STORAGE_ROCKSDB_INCLUDE_FILTER_POLICY_H_
-#define STORAGE_ROCKSDB_INCLUDE_FILTER_POLICY_H_
+#ifndef STORAGE_LEVELDB_INCLUDE_FILTER_POLICY_H_
+#define STORAGE_LEVELDB_INCLUDE_FILTER_POLICY_H_

 #include <string>

-namespace rocksdb {
+namespace leveldb {

 class Slice;

@@ -66,6 +66,5 @@ class FilterPolicy {
 extern const FilterPolicy* NewBloomFilterPolicy(int bits_per_key);

 }
-#include "rocksdb/rocksdb_to_leveldb.h"

-#endif  // STORAGE_ROCKSDB_INCLUDE_FILTER_POLICY_H_
+#endif  // STORAGE_LEVELDB_INCLUDE_FILTER_POLICY_H_
@@ -12,13 +12,13 @@
 // non-const method, all threads accessing the same Iterator must use
 // external synchronization.

-#ifndef STORAGE_ROCKSDB_INCLUDE_ITERATOR_H_
-#define STORAGE_ROCKSDB_INCLUDE_ITERATOR_H_
+#ifndef STORAGE_LEVELDB_INCLUDE_ITERATOR_H_
+#define STORAGE_LEVELDB_INCLUDE_ITERATOR_H_

-#include "rocksdb/slice.h"
-#include "rocksdb/status.h"
+#include "leveldb/slice.h"
+#include "leveldb/status.h"

-namespace rocksdb {
+namespace leveldb {

 class Iterator {
 public:
@@ -65,8 +65,6 @@ class Iterator {
  virtual Slice value() const = 0;

  // If an error has occurred, return it.  Else return an ok status.
-  // If non-blocking IO is requested and this operation cannot be
-  // satisfied without doing some IO, then this returns Status::Incomplete().
  virtual Status status() const = 0;

  // Clients are allowed to register function/arg1/arg2 triples that
@@ -97,8 +95,6 @@ extern Iterator* NewEmptyIterator();
 // Return an empty iterator with the specified status.
 extern Iterator* NewErrorIterator(const Status& status);

-}  // namespace rocksdb
+}  // namespace leveldb

-#include "rocksdb/rocksdb_to_leveldb.h"
-
-#endif  // STORAGE_ROCKSDB_INCLUDE_ITERATOR_H_
+#endif  // STORAGE_LEVELDB_INCLUDE_ITERATOR_H_
@@ -2,31 +2,25 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

-#ifndef STORAGE_ROCKSDB_INCLUDE_OPTIONS_H_
-#define STORAGE_ROCKSDB_INCLUDE_OPTIONS_H_
+#ifndef STORAGE_LEVELDB_INCLUDE_OPTIONS_H_
+#define STORAGE_LEVELDB_INCLUDE_OPTIONS_H_

 #include <stddef.h>
 #include <string>
 #include <memory>
 #include <vector>
 #include <stdint.h>
-#include "rocksdb/slice.h"
-#include "rocksdb/statistics.h"
-#include "rocksdb/universal_compaction.h"
-#include "rocksdb/memtablerep.h"
-#include "rocksdb/slice_transform.h"
+#include "leveldb/slice.h"

-namespace rocksdb {
+namespace leveldb {

 class Cache;
 class Comparator;
 class Env;
 class FilterPolicy;
 class Logger;
-class MergeOperator;
 class Snapshot;
-class CompactionFilter;
-class CompactionFilterFactory;
+class Statistics;

 using std::shared_ptr;

@@ -43,11 +37,6 @@ enum CompressionType {
  kBZip2Compression = 0x3
 };

-enum CompactionStyle {
-  kCompactionStyleLevel       = 0x0, // level based compaction style
-  kCompactionStyleUniversal   = 0x1  // Universal compaction style
-};
-
 // Compression options for different compression algorithms like Zlib
 struct CompressionOptions {
  int window_bits;
@@ -74,28 +63,6 @@ struct Options {
  // comparator provided to previous open calls on the same DB.
  const Comparator* comparator;

-  // REQUIRES: The client must provide a merge operator if Merge operation
-  // needs to be accessed. Calling Merge on a DB without a merge operator
-  // would result in Status::NotSupported. The client must ensure that the
-  // merge operator supplied here has the same name and *exactly* the same
-  // semantics as the merge operator provided to previous open calls on
-  // the same DB. The only exception is reserved for upgrade, where a DB
-  // previously without a merge operator is introduced to Merge operation
-  // for the first time. It's necessary to specify a merge operator when
-  // openning the DB in this case.
-  // Default: nullptr
-  shared_ptr<MergeOperator> merge_operator;
-
-  // The client must provide compaction_filter_factory if it requires a new
-  // compaction filter to be used for different compaction processes
-  // Allows an application to modify/delete a key-value during background
-  // compaction.
-  // Ideally, client should specify only one of filter or factory.
-  // compaction_filter takes precedence over compaction_filter_factory if
-  // client specifies both.
-  // Default: nullptr
-  const CompactionFilter* compaction_filter;
-
  // If true, the database will be created if it is missing.
  // Default: false
  bool create_if_missing;
@@ -145,15 +112,6 @@ struct Options {
  // Default: 2
  int max_write_buffer_number;

-  // The minimum number of write buffers that will be merged together
-  // before writing to storage.  If set to 1, then
-  // all write buffers are fushed to L0 as individual files and this increases
-  // read amplification because a get request has to check in all of these
-  // files. Also, an in-memory merge may result in writing lesser
-  // data to storage if there are duplicate records in each of these
-  // individual write buffers.  Default: 1
-  int min_write_buffer_number_to_merge;
-
  // Number of open files that can be used by the DB.  You may need to
  // increase this if your database has a large working set (budget
  // one open file per 2MB of working set).
@@ -225,28 +183,6 @@ struct Options {
  // Default: nullptr
  const FilterPolicy* filter_policy;

-  // If non-nullptr, use the specified function to determine the
-  // prefixes for keys.  These prefixes will be placed in the filter.
-  // Depending on the workload, this can reduce the number of read-IOP
-  // cost for scans when a prefix is passed via ReadOptions to
-  // db.NewIterator().  For prefix filtering to work properly,
-  // "prefix_extractor" and "comparator" must be such that the following
-  // properties hold:
-  //
-  // 1) key.starts_with(prefix(key))
-  // 2) Compare(prefix(key), key) <= 0.
-  // 3) If Compare(k1, k2) <= 0, then Compare(prefix(k1), prefix(k2)) <= 0
-  // 4) prefix(prefix(key)) == prefix(key)
-  //
-  // Default: nullptr
-  const SliceTransform* prefix_extractor;
-
-  // If true, place whole keys in the filter (not just prefixes).
-  // This must generally be true for gets to be efficient.
-  //
-  // Default: true
-  bool whole_key_filtering;
-
  // Number of levels for this database
  int num_levels;

@@ -254,9 +190,9 @@ struct Options {
  // level-0 compaction will not be triggered by number of files at all.
  int level0_file_num_compaction_trigger;

-  // Soft limit on number of level-0 files. We start slowing down writes at this
-  // point. A value <0 means that no writing slow down will be triggered by
-  // number of files in level-0.
+  // Soft limit on number of level-0 files. We slow down writes at this point.
+  // A value <0 means that no writing slow down will be triggered by number
+  // of files in level-0.
  int level0_slowdown_writes_trigger;

  // Maximum number of level-0 files.  We stop writes at this point.
@@ -300,12 +236,6 @@ struct Options {
  // by default 'max_bytes_for_level_base' is 10.
  int max_bytes_for_level_multiplier;

-  // Different max-size multipliers for different levels.
-  // These are multiplied by max_bytes_for_level_multiplier to arrive
-  // at the max-size of each level.
-  // Default: 1
-  std::vector<int> max_bytes_for_level_multiplier_additional;
-
  // Maximum number of bytes in all compacted files.  We avoid expanding
  // the lower level file set of a compaction if it would make the
  // total compaction cover more than
@@ -328,7 +258,7 @@ struct Options {
  // If non-null, then we should collect metrics about database operations
  // Statistics objects should not be shared between DB instances as
  // it does not use any locks to prevent concurrent updates.
-  shared_ptr<Statistics> statistics;
+  Statistics* statistics;

  // If true, then the contents of data files are not synced
  // to stable storage. Their contents remain in the OS buffers till the
@@ -369,23 +299,10 @@ struct Options {
  // every compaction run.
  uint64_t delete_obsolete_files_period_micros;

-  // Maximum number of concurrent background jobs, submitted to
-  // the default LOW priority thread pool
+  // Maximum number of concurrent background compactions.
  // Default: 1
  int max_background_compactions;

-  // Maximum number of concurrent background memtable flush jobs, submitted to
-  // the HIGH priority thread pool.
-  // By default, all background jobs (major compaction and memtable flush) go
-  // to the LOW priority pool. If this option is set to a positive number,
-  // memtable flush jobs will be submitted to the HIGH priority pool.
-  // It is important when the same Env is shared by multiple db instances.
-  // Without a separate pool, long running major compaction jobs could
-  // potentially block memtable flush jobs of other db instances, leading to
-  // unnecessary Put stalls.
-  // Default: 0
-  int max_background_flushes;
-
  // Specify the maximal size of the info log file. If the log file
  // is larger than `max_log_file_size`, a new info log file will
  // be created.
@@ -403,44 +320,26 @@ struct Options {
  // Default: 1000
  size_t keep_log_file_num;

-  // Puts are delayed 0-1 ms when any level has a compaction score that exceeds
-  // soft_rate_limit. This is ignored when == 0.0.
-  // CONSTRAINT: soft_rate_limit <= hard_rate_limit. If this constraint does not
-  // hold, RocksDB will set soft_rate_limit = hard_rate_limit
-  // Default: 0 (disabled)
-  double soft_rate_limit;
+  // Puts are delayed when any level has a compaction score that
+  // exceeds rate_limit. This is ignored when <= 1.0.
+  double rate_limit;

-  // Puts are delayed 1ms at a time when any level has a compaction score that
-  // exceeds hard_rate_limit. This is ignored when <= 1.0.
-  // Default: 0 (disabled)
-  double hard_rate_limit;
-
-  // Max time a put will be stalled when hard_rate_limit is enforced. If 0, then
-  // there is no limit.
-  // Default: 1000
-  unsigned int rate_limit_delay_max_milliseconds;
+  // Max time a put will be stalled when rate_limit is enforced
+  int rate_limit_delay_milliseconds;

  // manifest file is rolled over on reaching this limit.
  // The older manifest file be deleted.
  // The default value is MAX_INT so that roll-over does not take place.
  uint64_t max_manifest_file_size;

-  // Disable block cache. If this is set to true,
+  // Disable block cache. If this is set to false,
  // then no block cache should be used, and the block_cache should
  // point to a nullptr object.
-  // Default: false
  bool no_block_cache;

  // Number of shards used for table cache.
  int table_cache_numshardbits;

-  // size of one block in arena memory allocation.
-  // If <= 0, a proper value is automatically calculated (usually 1/10 of
-  // writer_buffer_size).
-  //
-  // Default: 0
-  size_t arena_block_size;
-
  // Create an Options object with default values for all fields.
  Options();

@@ -455,6 +354,25 @@ struct Options {
  // from the database, because otherwise the read can be very slow.
  Options* PrepareForBulkLoad();

+  // This method allows an application to modify/delete a key-value at
+  // the time of compaction. The compaction process invokes this
+  // method for every kv that is being compacted. A return value
+  // of false indicates that the kv should be preserved in the
+  // output of this compaction run and a return value of true
+  // indicates that this key-value should be removed from the
+  // output of the compaction.  The application can inspect
+  // the existing value of the key, modify it if needed and
+  // return back the new value for this key. The application
+  // should allocate memory for the Slice object that is used to
+  // return the new value and the leveldb framework will
+  // free up that memory.
+  // The compaction_filter_args, if specified here, are passed
+  // back to the invocation of the CompactionFilter.
+  void* compaction_filter_args;
+  bool (*CompactionFilter)(void* compaction_filter_args,
+         int level, const Slice& key,
+         const Slice& existing_value, Slice** new_value);
+
  // Disable automatic compactions. Manual compactions can still
  // be issued on this database.
  bool disable_auto_compactions;
@@ -478,106 +396,6 @@ struct Options {
  // Purge duplicate/deleted keys when a memtable is flushed to storage.
  // Default: true
  bool purge_redundant_kvs_while_flush;
-
-  // Data being read from file storage may be buffered in the OS
-  // Default: true
-  bool allow_os_buffer;
-
-  // Allow the OS to mmap file for reading sst tables. Default: false
-  bool allow_mmap_reads;
-
-  // Allow the OS to mmap file for writing. Default: true
-  bool allow_mmap_writes;
-
-  // Disable child process inherit open files. Default: true
-  bool is_fd_close_on_exec;
-
-  // Skip log corruption error on recovery (If client is ok with
-  // losing most recent changes)
-  // Default: false
-  bool skip_log_error_on_recovery;
-
-  // if not zero, dump leveldb.stats to LOG every stats_dump_period_sec
-  // Default: 3600 (1 hour)
-  unsigned int stats_dump_period_sec;
-
-  // This is used to close a block before it reaches the configured
-  // 'block_size'. If the percentage of free space in the current block is less
-  // than this specified number and adding a new record to the block will
-  // exceed the configured block size, then this block will be closed and the
-  // new record will be written to the next block.
-  // Default is 10.
-  int block_size_deviation;
-
-  // If set true, will hint the underlying file system that the file
-  // access pattern is random, when a sst file is opened.
-  // Default: true
-  bool advise_random_on_open;
-
-  // Specify the file access pattern once a compaction is started.
-  // It will be applied to all input files of a compaction.
-  // Default: NORMAL
-  enum { NONE, NORMAL, SEQUENTIAL, WILLNEED } access_hint_on_compaction_start;
-
-  // Use adaptive mutex, which spins in the user space before resorting
-  // to kernel. This could reduce context switch when the mutex is not
-  // heavily contended. However, if the mutex is hot, we could end up
-  // wasting spin time.
-  // Default: false
-  bool use_adaptive_mutex;
-
-  // Allows OS to incrementally sync files to disk while they are being
-  // written, asynchronously, in the background.
-  // Issue one request for every bytes_per_sync written. 0 turns it off.
-  // Default: 0
-  uint64_t bytes_per_sync;
-
-  // The compaction style. Default: kCompactionStyleLevel
-  CompactionStyle compaction_style;
-
-  // The options needed to support Universal Style compactions
-  CompactionOptionsUniversal compaction_options_universal;
-
-  // Use KeyMayExist API to filter deletes when this is true.
-  // If KeyMayExist returns false, i.e. the key definitely does not exist, then
-  // the delete is a noop. KeyMayExist only incurs in-memory look up.
-  // This optimization avoids writing the delete to storage when appropriate.
-  // Default: false
-  bool filter_deletes;
-
-  // An iteration->Next() sequentially skips over keys with the same
-  // user-key unless this option is set. This number specifies the number
-  // of keys (with the same userkey) that will be sequentially
-  // skipped before a reseek is issued.
-  // Default: 8
-  uint64_t max_sequential_skip_in_iterations;
-
-  // This is a factory that provides MemTableRep objects.
-  // Default: a factory that provides a skip-list-based implementation of
-  // MemTableRep.
-  std::shared_ptr<MemTableRepFactory> memtable_factory;
-
-  // This is a factory that provides compaction filter objects which allow
-  // an application to modify/delete a key-value during background compaction.
-  // Default: a factory that doesn't provide any object
-  std::shared_ptr<CompactionFilterFactory> compaction_filter_factory;
-
-  // Remove the log file immediately after the corresponding memtable is flushed
-  // to data file.
-  // Default: true
-  bool purge_log_after_memtable_flush;
-};
-
-//
-// An application can issue a read request (via Get/Iterators) and specify
-// if that read should process data that ALREADY resides on a specified cache
-// level. For example, if an application specifies kBlockCacheTier then the
-// Get call will process data that is already processed in the memtable or
-// the block cache. It will not page in data from the OS cache or data that
-// resides in storage.
-enum ReadTier {
-  kReadAllTier    = 0x0, // data in memtable, block cache, OS cache or storage
-  kBlockCacheTier = 0x1  // data in memtable or block cache
 };

 // Options that control read operations
@@ -599,36 +417,14 @@ struct ReadOptions {
  // Default: nullptr
  const Snapshot* snapshot;

-  // If "prefix" is non-nullptr, and ReadOptions is being passed to
-  // db.NewIterator, only return results when the key begins with this
-  // prefix.  This field is ignored by other calls (e.g., Get).
-  // Options.prefix_extractor must also be set, and
-  // prefix_extractor.InRange(prefix) must be true.  The iterator
-  // returned by NewIterator when this option is set will behave just
-  // as if the underlying store did not contain any non-matching keys,
-  // with two exceptions.  Seek() only accepts keys starting with the
-  // prefix, and SeekToLast() is not supported.  prefix filter with this
-  // option will sometimes reduce the number of read IOPs.
-  // Default: nullptr
-  const Slice* prefix;
-
-  // Specify if this read request should process data that ALREADY
-  // resides on a particular cache. If the required data is not
-  // found at the specified cache, then Status::Incomplete is returned.
-  // Default: kReadAllTier
-  ReadTier read_tier;
-
  ReadOptions()
      : verify_checksums(false),
        fill_cache(true),
-        snapshot(nullptr),
-        prefix(nullptr),
-        read_tier(kReadAllTier) {
+        snapshot(nullptr) {
  }
  ReadOptions(bool cksum, bool cache) :
              verify_checksums(cksum), fill_cache(cache),
-              snapshot(nullptr), prefix(nullptr),
-              read_tier(kReadAllTier) {
+              snapshot(nullptr) {
  }
 };

@@ -673,8 +469,6 @@ struct FlushOptions {
  }
 };

-}  // namespace rocksdb
+}  // namespace leveldb

-#include "rocksdb/rocksdb_to_leveldb.h"
-
-#endif  // STORAGE_ROCKSDB_INCLUDE_OPTIONS_H_
+#endif  // STORAGE_LEVELDB_INCLUDE_OPTIONS_H_
@@ -12,15 +12,15 @@
 // non-const method, all threads accessing the same Slice must use
 // external synchronization.

-#ifndef STORAGE_ROCKSDB_INCLUDE_SLICE_H_
-#define STORAGE_ROCKSDB_INCLUDE_SLICE_H_
+#ifndef STORAGE_LEVELDB_INCLUDE_SLICE_H_
+#define STORAGE_LEVELDB_INCLUDE_SLICE_H_

 #include <assert.h>
 #include <stddef.h>
 #include <string.h>
 #include <string>

-namespace rocksdb {
+namespace leveldb {

 class Slice {
 public:
@@ -31,11 +31,9 @@ class Slice {
  Slice(const char* d, size_t n) : data_(d), size_(n) { }

  // Create a slice that refers to the contents of "s"
-  /* implicit */
  Slice(const std::string& s) : data_(s.data()), size_(s.size()) { }

  // Create a slice that refers to s[0,strlen(s)-1]
-  /* implicit */
  Slice(const char* s) : data_(s), size_(strlen(s)) { }

  // Return a pointer to the beginning of the referenced data
@@ -117,8 +115,7 @@ inline int Slice::compare(const Slice& b) const {
  return r;
 }

-}  // namespace rocksdb
+}  // namespace leveldb

-#include "rocksdb/rocksdb_to_leveldb.h"

-#endif  // STORAGE_ROCKSDB_INCLUDE_SLICE_H_
+#endif  // STORAGE_LEVELDB_INCLUDE_SLICE_H_
@@ -0,0 +1,136 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#ifndef STORAGE_LEVELDB_INCLUDE_STATISTICS_H_
+#define STORAGE_LEVELDB_INCLUDE_STATISTICS_H_
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+#include <memory>
+
+namespace leveldb {
+
+/**
+ * Keep adding ticker's here.
+ * Any ticker should have a value less than TICKER_ENUM_MAX.
+ * Add a new ticker by assigning it the current value of TICKER_ENUM_MAX
+ * And incrementing TICKER_ENUM_MAX.
+ */
+enum Tickers {
+  BLOCK_CACHE_MISS = 0,
+  BLOCK_CACHE_HIT = 1,
+  BLOOM_FILTER_USEFUL = 2, // no. of times bloom filter has avoided file reads.
+  /**
+   * COMPACTION_KEY_DROP_* count the reasons for key drop during compaction
+   * There are 3 reasons currently.
+   */
+  COMPACTION_KEY_DROP_NEWER_ENTRY = 3, // key was written with a newer value.
+  COMPACTION_KEY_DROP_OBSOLETE = 4, // The key is obsolete.
+  COMPACTION_KEY_DROP_USER = 5, // user compaction function has dropped the key.
+  // Number of keys written to the database via the Put and Write call's
+  NUMBER_KEYS_WRITTEN = 6,
+  // Number of Keys read,
+  NUMBER_KEYS_READ = 7,
+  // Bytes written / read
+  BYTES_WRITTEN = 8,
+  BYTES_READ = 9,
+  NO_FILE_CLOSES = 10,
+  NO_FILE_OPENS = 11,
+  NO_FILE_ERRORS = 12,
+  TICKER_ENUM_MAX = 13,
+};
+
+
+/**
+ * Keep adding histogram's here.
+ * Any histogram whould have value less than HISTOGRAM_ENUM_MAX
+ * Add a new Histogram by assigning it the current value of HISTOGRAM_ENUM_MAX
+ * And increment HISTOGRAM_ENUM_MAX
+ */
+enum Histograms {
+  DB_GET = 0,
+  DB_WRITE = 1,
+  COMPACTION_TIME = 2,
+  HISTOGRAM_ENUM_MAX = 3,
+};
+
+struct HistogramData {
+  double median;
+  double percentile95;
+  double percentile99;
+  double average;
+  double standard_deviation;
+};
+
+
+class Histogram {
+ public:
+  // clear's the histogram
+  virtual void Clear() = 0;
+  virtual ~Histogram();
+  // Add a value to be recorded in the histogram.
+  virtual void Add(uint64_t value) = 0;
+  virtual void Add(double value) = 0;
+
+  virtual std::string ToString() const = 0;
+
+  // Get statistics
+  virtual double Median() const = 0;
+  virtual double Percentile(double p) const = 0;
+  virtual double Average() const = 0;
+  virtual double StandardDeviation() const = 0;
+  virtual void Data(HistogramData * const data) const = 0;
+
+};
+
+/**
+ * A dumb ticker which keeps incrementing through its life time.
+ * Not thread safe. Locking is currently managed by external leveldb lock
+ */
+class Ticker {
+ public:
+  Ticker() : count_(0) { }
+
+  inline void recordTick() {
+    count_++;
+  }
+
+  inline void recordTick(int count) {
+    count_ += count;
+  }
+
+  inline uint64_t getCount() {
+    return count_;
+  }
+
+ private:
+  uint64_t count_;
+
+};
+
+// Analyze the performance of a db
+class Statistics {
+ public:
+
+  virtual long getTickerCount(Tickers tickerType) = 0;
+  virtual void recordTick(Tickers tickerType, uint64_t count = 0) = 0;
+  virtual void measureTime(Histograms histogramType, uint64_t count) = 0;
+  virtual void measureTime(Histograms histogramType, double count) = 0;
+
+  virtual void histogramData(Histograms type, HistogramData * const data) = 0;
+
+};
+
+// Ease of Use functions
+inline void RecordTick(Statistics* const statistics,
+                       Tickers ticker,
+                       uint64_t count = 1) {
+  if (statistics != nullptr) {
+    statistics->recordTick(ticker, count);
+  }
+}
+}  // namespace leveldb
+
+#endif  // STORAGE_LEVELDB_INCLUDE_STATISTICS_H_
@@ -10,13 +10,13 @@
 // non-const method, all threads accessing the same Status must use
 // external synchronization.

-#ifndef STORAGE_ROCKSDB_INCLUDE_STATUS_H_
-#define STORAGE_ROCKSDB_INCLUDE_STATUS_H_
+#ifndef STORAGE_LEVELDB_INCLUDE_STATUS_H_
+#define STORAGE_LEVELDB_INCLUDE_STATUS_H_

 #include <string>
-#include "rocksdb/slice.h"
+#include "leveldb/slice.h"

-namespace rocksdb {
+namespace leveldb {

 class Status {
 public:
@@ -47,12 +47,6 @@ class Status {
  static Status IOError(const Slice& msg, const Slice& msg2 = Slice()) {
    return Status(kIOError, msg, msg2);
  }
-  static Status MergeInProgress(const Slice& msg, const Slice& msg2 = Slice()) {
-    return Status(kMergeInProgress, msg, msg2);
-  }
-  static Status Incomplete(const Slice& msg, const Slice& msg2 = Slice()) {
-    return Status(kIncomplete, msg, msg2);
-  }

  // Returns true iff the status indicates success.
  bool ok() const { return (state_ == nullptr); }
@@ -72,12 +66,6 @@ class Status {
  // Returns true iff the status indicates an IOError.
  bool IsIOError() const { return code() == kIOError; }

-  // Returns true iff the status indicates an MergeInProgress.
-  bool IsMergeInProgress() const { return code() == kMergeInProgress; }
-
-  // Returns true iff the status indicates Incomplete
-  bool IsIncomplete() const { return code() == kIncomplete; }
-
  // Return a string representation of this status suitable for printing.
  // Returns the string "OK" for success.
  std::string ToString() const;
@@ -96,9 +84,7 @@ class Status {
    kCorruption = 2,
    kNotSupported = 3,
    kInvalidArgument = 4,
-    kIOError = 5,
-    kMergeInProgress = 6,
-    kIncomplete = 7
+    kIOError = 5
  };

  Code code() const {
@@ -121,8 +107,6 @@ inline void Status::operator=(const Status& s) {
  }
 }

-}  // namespace rocksdb
+}  // namespace leveldb

-#include "rocksdb/rocksdb_to_leveldb.h"
-
-#endif  // STORAGE_ROCKSDB_INCLUDE_STATUS_H_
+#endif  // STORAGE_LEVELDB_INCLUDE_STATUS_H_
@@ -7,10 +7,9 @@

 #include <memory>
 #include <stdint.h>
-#include "rocksdb/iterator.h"
-#include "rocksdb/env.h"
+#include "leveldb/iterator.h"

-namespace rocksdb {
+namespace leveldb {

 class Block;
 class BlockHandle;
@@ -40,15 +39,12 @@ class Table {
  //
  // *file must remain live while this Table is in use.
  static Status Open(const Options& options,
-                     const EnvOptions& soptions,
                     unique_ptr<RandomAccessFile>&& file,
                     uint64_t file_size,
                     unique_ptr<Table>* table);

  ~Table();

-  bool PrefixMayMatch(const Slice& internal_prefix) const;
-
  // Returns a new iterator over the table contents.
  // The result of NewIterator() is initially invalid (caller must
  // call one of the Seek methods on the iterator before using it).
@@ -66,30 +62,23 @@ class Table {
  // REQUIRES: key is in this table.
  bool TEST_KeyInCache(const ReadOptions& options, const Slice& key);

-  // Set up the table for Compaction. Might change some parameters with
-  // posix_fadvise
-  void SetupForCompaction();
-
 private:
  struct Rep;
  Rep* rep_;
-  bool compaction_optimized_;
-  explicit Table(Rep* rep) : compaction_optimized_(false) { rep_ = rep; }
-  static Iterator* BlockReader(void*, const ReadOptions&,
-                               const EnvOptions& soptions, const Slice&,
-                               bool for_compaction);
-  static Iterator* BlockReader(void*, const ReadOptions&, const Slice&,
-                               bool* didIO, bool for_compaction = false);

-  // Calls (*handle_result)(arg, ...) repeatedly, starting with the entry found
-  // after a call to Seek(key), until handle_result returns false.
-  // May not make such a call if filter policy says that key is not present.
+  explicit Table(Rep* rep) { rep_ = rep; }
+  static Iterator* BlockReader(void*, const ReadOptions&, const Slice&);
+  static Iterator* BlockReader(void*, const ReadOptions&, const Slice&,
+                               bool* didIO);
+
+  // Calls (*handle_result)(arg, ...) with the entry found after a call
+  // to Seek(key).  May not make such a call if filter policy says
+  // that key is not present.
  friend class TableCache;
  Status InternalGet(
      const ReadOptions&, const Slice& key,
      void* arg,
-      bool (*handle_result)(void* arg, const Slice& k, const Slice& v, bool),
-      void (*mark_key_may_exist)(void*) = nullptr);
+      void (*handle_result)(void* arg, const Slice& k, const Slice& v, bool));


  void ReadMeta(const Footer& footer);
@@ -102,6 +91,6 @@ class Table {
  void operator=(const Table&);
 };

-}  // namespace rocksdb
+}  // namespace leveldb

 #endif  // STORAGE_LEVELDB_INCLUDE_TABLE_H_
@@ -10,14 +10,14 @@
 // non-const method, all threads accessing the same TableBuilder must use
 // external synchronization.

-#ifndef STORAGE_ROCKSDB_INCLUDE_TABLE_BUILDER_H_
-#define STORAGE_ROCKSDB_INCLUDE_TABLE_BUILDER_H_
+#ifndef STORAGE_LEVELDB_INCLUDE_TABLE_BUILDER_H_
+#define STORAGE_LEVELDB_INCLUDE_TABLE_BUILDER_H_

 #include <stdint.h>
-#include "rocksdb/options.h"
-#include "rocksdb/status.h"
+#include "leveldb/options.h"
+#include "leveldb/status.h"

-namespace rocksdb {
+namespace leveldb {

 class BlockBuilder;
 class BlockHandle;
@@ -90,8 +90,6 @@ class TableBuilder {
  void operator=(const TableBuilder&);
 };

-}  // namespace rocksdb
+}  // namespace leveldb

-#include "rocksdb/rocksdb_to_leveldb.h"
-
-#endif  // STORAGE_ROCKSDB_INCLUDE_TABLE_BUILDER_H_
+#endif  // STORAGE_LEVELDB_INCLUDE_TABLE_BUILDER_H_
@@ -0,0 +1,42 @@
+// Copyright 2008-present Facebook. All Rights Reserved.
+#ifndef STORAGE_LEVELDB_INCLUDE_TRANSACTION_LOG_ITERATOR_H_
+#define STORAGE_LEVELDB_INCLUDE_TRANSACTION_LOG_ITERATOR_H_
+
+#include "leveldb/status.h"
+#include "leveldb/write_batch.h"
+
+namespace leveldb {
+
+
+struct BatchResult {
+  SequenceNumber sequence;
+  std::unique_ptr<WriteBatch> writeBatchPtr;
+};
+
+//  A TransactionLogIterator is used to iterate over the Transaction's in a db.
+class TransactionLogIterator {
+ public:
+  TransactionLogIterator() {}
+  virtual ~TransactionLogIterator() {}
+
+  // An iterator is either positioned at a WriteBatch or not valid.
+  // This method returns true if the iterator is valid.
+  // Can read data from a valid iterator.
+  virtual bool Valid() = 0;
+
+  // Moves the iterator to the next WriteBatch.
+  // REQUIRES: Valid() to be true.
+  virtual void Next() = 0;
+
+  // Return's ok if the iterator is valid.
+  // Return the Error when something has gone wrong.
+  virtual Status status() = 0;
+
+  // If valid return's the current write_batch and the sequence number of the
+  // latest transaction contained in the batch.
+  // ONLY use if Valid() is true and status() is OK.
+  virtual BatchResult GetBatch() = 0;
+};
+} //  namespace leveldb
+
+#endif  // STORAGE_LEVELDB_INCLUDE_TRANSACTION_LOG_ITERATOR_H_
@@ -0,0 +1,14 @@
+#ifndef STORAGE_LEVELDB_INCLUDE_TYPES_H_
+#define STORAGE_LEVELDB_INCLUDE_TYPES_H_
+
+#include <stdint.h>
+
+namespace leveldb {
+
+// Define all public custom types here.
+
+//  Represents a sequence number in a WAL file.
+typedef uint64_t SequenceNumber;
+
+}  //  namespace leveldb
+#endif //  STORAGE_LEVELDB_INCLUDE_TYPES_H_
@@ -0,0 +1,70 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//
+// WriteBatch holds a collection of updates to apply atomically to a DB.
+//
+// The updates are applied in the order in which they are added
+// to the WriteBatch.  For example, the value of "key" will be "v3"
+// after the following batch is written:
+//
+//    batch.Put("key", "v1");
+//    batch.Delete("key");
+//    batch.Put("key", "v2");
+//    batch.Put("key", "v3");
+//
+// Multiple threads can invoke const methods on a WriteBatch without
+// external synchronization, but if any of the threads may call a
+// non-const method, all threads accessing the same WriteBatch must use
+// external synchronization.
+
+#ifndef STORAGE_LEVELDB_INCLUDE_WRITE_BATCH_H_
+#define STORAGE_LEVELDB_INCLUDE_WRITE_BATCH_H_
+
+#include <string>
+#include "leveldb/status.h"
+
+namespace leveldb {
+
+class Slice;
+
+class WriteBatch {
+ public:
+  WriteBatch();
+  ~WriteBatch();
+
+  // Store the mapping "key->value" in the database.
+  void Put(const Slice& key, const Slice& value);
+
+  // If the database contains a mapping for "key", erase it.  Else do nothing.
+  void Delete(const Slice& key);
+
+  // Clear all updates buffered in this batch.
+  void Clear();
+
+  // Support for iterating over the contents of a batch.
+  class Handler {
+   public:
+    virtual ~Handler();
+    virtual void Put(const Slice& key, const Slice& value) = 0;
+    virtual void Delete(const Slice& key) = 0;
+  };
+  Status Iterate(Handler* handler) const;
+
+  // Retrive the serialized version of this batch.
+  std::string Data() { return rep_; }
+
+  // Constructor with a serialized string object
+  WriteBatch(std::string rep): rep_(rep) {}
+
+ private:
+  friend class WriteBatchInternal;
+
+  std::string rep_;  // See comment in write_batch.cc for the format of rep_
+
+  // Intentionally copyable
+};
+
+}  // namespace leveldb
+
+#endif  // STORAGE_LEVELDB_INCLUDE_WRITE_BATCH_H_
@@ -1,43 +0,0 @@
-// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file. See the AUTHORS file for names of contributors.
-//
-// Arena class defines memory allocation methods. It's used by memtable and
-// skiplist.
-
-#ifndef STORAGE_ROCKSDB_INCLUDE_ARENA_H_
-#define STORAGE_ROCKSDB_INCLUDE_ARENA_H_
-
-#include <limits>
-#include <memory>
-
-namespace rocksdb {
-
-class Arena {
- public:
-  Arena() {};
-  virtual ~Arena() {};
-
-  // Return a pointer to a newly allocated memory block of "bytes" bytes.
-  virtual char* Allocate(size_t bytes) = 0;
-
-  // Allocate memory with the normal alignment guarantees provided by malloc.
-  virtual char* AllocateAligned(size_t bytes) = 0;
-
-  // Returns an estimate of the total memory used by arena.
-  virtual const size_t ApproximateMemoryUsage() = 0;
-
-  // Returns the total number of bytes in all blocks allocated so far.
-  virtual const size_t MemoryAllocatedBytes() = 0;
-
- private:
-  // No copying allowed
-  Arena(const Arena&);
-  void operator=(const Arena&);
-};
-
-}  // namespace rocksdb
-
-#include "rocksdb/rocksdb_to_leveldb.h"
-
-#endif  // STORAGE_ROCKSDB_INCLUDE_ARENA_H_
@@ -1,73 +0,0 @@
-// Copyright (c) 2013 The LevelDB Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file. See the AUTHORS file for names of contributors.
-
-#ifndef STORAGE_ROCKSDB_INCLUDE_COMPACTION_FILTER_H_
-#define STORAGE_ROCKSDB_INCLUDE_COMPACTION_FILTER_H_
-
-#include <string>
-
-namespace rocksdb {
-
-class Slice;
-
-// CompactionFilter allows an application to modify/delete a key-value at
-// the time of compaction.
-
-class CompactionFilter {
- public:
-  virtual ~CompactionFilter() {}
-
-
-  // The compaction process invokes this
-  // method for kv that is being compacted. A return value
-  // of false indicates that the kv should be preserved in the
-  // output of this compaction run and a return value of true
-  // indicates that this key-value should be removed from the
-  // output of the compaction.  The application can inspect
-  // the existing value of the key and make decision based on it.
-  //
-  // When the value is to be preserved, the application has the option
-  // to modify the existing_value and pass it back through new_value.
-  // value_changed needs to be set to true in this case.
-  virtual bool Filter(int level,
-                      const Slice& key,
-                      const Slice& existing_value,
-                      std::string* new_value,
-                      bool* value_changed) const = 0;
-
-  // Returns a name that identifies this compaction filter.
-  // The name will be printed to LOG file on start up for diagnosis.
-  virtual const char* Name() const = 0;
-};
-
-// Each compaction will create a new CompactionFilter allowing the
-// application to know about different campactions
-class CompactionFilterFactory {
-  public:
-    virtual ~CompactionFilterFactory() { };
-    virtual std::unique_ptr<CompactionFilter> CreateCompactionFilter() = 0;
-
-    // Returns a name that identifies this compaction filter factory.
-    virtual const char* Name() const = 0;
-};
-
-// Default implementaion of CompactionFilterFactory which does not
-// return any filter
-class DefaultCompactionFilterFactory : public CompactionFilterFactory {
-  public:
-    virtual std::unique_ptr<CompactionFilter>
-    CreateCompactionFilter() override {
-      return std::unique_ptr<CompactionFilter>(nullptr);
-    }
-
-    virtual const char* Name() const override {
-      return "DefaultCompactionFilterFactory";
-    }
-};
-
-}  // namespace rocksdb
-
-#include "rocksdb/rocksdb_to_leveldb.h"
-
-#endif  // STORAGE_ROCKSDB_INCLUDE_COMPACTION_FILTER_H_
@@ -1,20 +0,0 @@
-// Copyright 2008-present Facebook. All Rights Reserved.
-#ifndef STORAGE_ROCKSDB_INCLUDE_LDB_TOOL_H
-#define STORAGE_ROCKSDB_INCLUDE_LDB_TOOL_H
-#include "rocksdb/options.h"
-
-namespace rocksdb {
-
-class LDBTool {
- public:
-  void Run(int argc, char** argv, Options = Options());
-};
-
-namespace leveldb = rocksdb;
-
-
-} // namespace rocksdb
-
-#include "rocksdb/rocksdb_to_leveldb.h"
-
-#endif // STORAGE_ROCKSDB_INCLUDE_LDB_TOOL_H