Summary:
This PR adds support for custom file systems to ldb and sst_dump by adding command line options for specifying --fs_uri and --backup_fs uri (for ldb backup/restore commands). fs_uri is already supported in db_bench and db_stress, and there is already support in ldb and db stress for specifying customized envs.
The PR also fixes what looks like a bug in the ldb backup/restore commands. As it is right now, backups can only be made from and to the same environment/file system which does not seem to be the intended behavior. This PR makes it possible to do/restore backups between different envs/file systems.
Example:
`./ldb backup --fs_uri=zenfs://dev:nvme2n1 --backup_fs_uri=posix:// --backup_dir=/tmp/my_rocksdb_backup --db=rocksdbtest/dbbench
`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8010
Reviewed By: jay-zhuang
Differential Revision: D26904654
Pulled By: ajkr
fbshipit-source-id: 9b695ed8b944fcc6b27c4daaa9f52e87ee2c1fb4
670567db09