fork of https://github.com/oxigraph/rocksdb and https://github.com/facebook/rocksdb for nextgraph and oxigraph

Andrew Kryczka e5e545a021 Reunite checkpoint and backup core logic ... Summary: These code paths forked when checkpoint was introduced by copy/pasting the core backup logic. Over time they diverged and bug fixes were sometimes applied to one but not the other (like fix to include all relevant WALs for 2PC), or it required extra effort to fix both (like fix to forge CURRENT file). This diff reunites the code paths by extracting the core logic into a function, CreateCustomCheckpoint(), that is customizable via callbacks to implement both checkpoint and backup. Related changes: - flush_before_backup is now forcibly enabled when 2PC is enabled - Extracted CheckpointImpl class definition into a header file. This is so the function, CreateCustomCheckpoint(), can be called by internal rocksdb code but not exposed to users. - Implemented more functions in DummyDB/DummyLogFile (in backupable_db_test.cc) that are used by CreateCustomCheckpoint(). Closes https://github.com/facebook/rocksdb/pull/1932 Differential Revision: D4622986 Pulled By: ajkr fbshipit-source-id: 157723884236ee3999a682673b64f7457a7a0d87		8 years ago
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checkpoint_impl.cc	Reunite checkpoint and backup core logic	8 years ago
checkpoint_impl.h	Reunite checkpoint and backup core logic	8 years ago
checkpoint_test.cc	Allow checkpointing without flushing	8 years ago