Log message:
leveldb: updated to 1.23

1.23

Sync MANIFEST before closing in db_impl when creating a new DB. Add logging with \ 
debugging information when failing to load a version set.
Optimize leveldb block seeks to utilize the current iterator location. This is \ 
beneficial when iterators are reused and seeks are not random but increasing. It \ 
is additionally beneficial with larger block sizes and keys with common \ 
prefixes.
Documentation fixes
(cmumford/printf-fix) Fixed fprintf of 64-bit value.
(cmumford/benchmark) Added google/benchmark submodule.
Internal test cleanup
Internal cleanup migrating StatusOr.
avoid unnecessary memory copy
Fix accidental double std:: qualifiers.
Add some std:: qualifiers to types and functions.
Switch from C headers to C++ headers.
change const to constexpr
remove unnessary status judge
Remove leveldb::port::kLittleEndian.
Remove Windows workarounds in some tests.
Add Env::Remove{File,Dir} which obsolete Env::Delete{File,Dir}.
Defend against inclusion of windows.h in tests that invoke Env::DeleteFile.
Add WITHOUT ROWID to SQLite benchmark.
Switch testing harness to googletest.
Move CI to Visual Studio 2019.
Allow different C/C++ standards when this is used as a subproject.
Align CMake configuration with related projects.
Remove redundant PROJECT_SOURCE_DIR usage from CMake config.
Fix installed target definition.
Added return in Version::Get::State::Match to quiet warning.
Using CMake's check_cxx_compiler_flag to check support for -Wthread-safety.
Fix tsan problem in env_test.
Simplify unlocking in DeleteObsoleteFiles.
Add "leveldb" subdirectory to public include paths.
Align EnvPosix and EnvWindows.
Disable exceptions and RTTI in CMake configuration.
cache Saver in State object
fix bug(uninitialized options pointer in State)
remove TODO in Version::ForEachOverlapping
use ForEachOverlapping to impl Get
unsigned char -> uint8_t
Add explicit typecasts to avoid compiler warning.
Guard DBImpl::versions_ by mutex_.
Converted two for-loops to while-loops.
Switch to using C++ 11 override specifier.
Added unit test for InternalKey::DecodeFrom with empty string.
Using std::ostringstream in key DebugString.
Fix EnvPosix tests on Travis CI.
Clean up util/coding.{h,cc}.
Initialize Stats::start_ before first use in Stats::Start().
Add argument definition for void c functions.
Consolidate benchmark code to benchmarks/.
Convert missed virtual -> override in db_test.cc.
don't check current key in DBIter::Next()
Add O_CLOEXEC to open calls.
broken db: fix assertion in leveldb::InternalKey::Encode, mark base as corrupt
set const property
reduce lock's range in DeleteObsoleteFiles
block_builder header file dependency fixed

Log message:
databases: Replace RMD160 checksums with BLAKE2s checksums

All checksums have been double-checked against existing RMD160 and
SHA512 hashes

The following distfiles could not be fetched (some may be only fetched
conditionally):

./databases/cstore/distinfo D6.data.ros.gz
./databases/cstore/distinfo cstore0.2.tar.gz
./databases/cstore/distinfo data4.tar.gz

Log message:
databases: Remove SHA1 distfile hashes

Log message:
leveldb: Enable -fPIC to avoid link errors by consumer, upcoming librime-1.7.2

Log message:
leveldb: updated to 1.22

Release 1.22
Corrected formatting to be compliant with the Google C++ Style Guide.
Specifically export the WriteBatch::Handler inner class for Windows link.
Merge pull request 665 from cheng-chang:coding.
Merge pull request 669 from pavel-pimenov:fix-readme-windows-mkdir.
Merge pull request 472 from zhoudayang:patch-1.
Merge pull request 339 from richcole-at-amazon:master.
Restore soname versioning with CMake build.
Other miscellaneous cleanups, fixes, and improvements.

Release 1.21
Switched to using Copybara for project synchronization.
Minor cleanup in ports.
Silence unused argument warnings in MSVC.
Add tests for empty keys and values.
Switch corruption_test to use InMemEnv.
Replace AtomicPointer with std::atomic.
Make InMemoryEnv more consistent with filesystem based Env's.
Align windows_logger with posix_logger.
Improve CI configuration and added AppVeyor (Windows CI) badge to README.
Added native support for Windows.
Make WriteBatch::ApproximateSize() const.
Fix PosixWritableFile::Sync() on Apple systems.
Fix fdatasync() feature detection in opensource build.
C++11 cleanup for util/mutexlock.h.
Rework threading in env_posix.cc.
Remove InitOnce from the port API.
Expose WriteBatch::Append().
Fix documentation for log file growth.
Add move constructor to Status.
Replace port_posix with port_stdcxx.
Reimplement ConsumeDecimalNumber.
Document the building process.
Replace NULL with nullptr in C++ files.
Remove PLATFORM_IS_LITTLE_ENDIAN from port/posix.h.
Add more thread safety annotations.
Require C++11.
Replace SIZE_MAX with std::numeric_limits.
Add CMake build support.
Enable thread safety annotations.
leveldb::DestroyDB will now delete empty directories.
Replace SSE-optimized CRC32C in POSIX port with external library.
Fix file writing bug in CL 170738066.
Fix use of uninitialized value in LRUHandle.
Fix issue 474: a race between the f*_unlocked() STDIO calls in env_posix.cc and \ 
concurrent application calls to fflush(NULL).
Use __APPLE__ instead of OS_MACOS. The former is compiler-provided.
Report missing CURRENT manifest file as database corruption.
LevelDB: Add WriteBatch::ApproximateSize().
Other minor fixes, code cleanup, and documentation improvements.

Log message:
Don't hard-code -lgcc_s on NetBSD.

Log message:
Import leveldb-1.20 as databases/leveldb.

Packaged for wip by Mike M. Volokhov and myself.

LevelDB is a fast key-value storage library written at Google that
provides an ordered mapping from string keys to string values.