Re: refactoring basebackup.c

Justin Pryzby <pryzby@telsasoft.com>

From: Justin Pryzby <pryzby@telsasoft.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Jeevan Ladhe <jeevanladhe.os@gmail.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, "Shinoda, Noriyoshi (PN Japan FSIP)" <noriyoshi.shinoda@hpe.com>, Dipesh Pandit <dipesh.pandit@gmail.com>, Abhijit Menon-Sen <ams@toroid.org>, Dmitry Dolgov <9erthalion6@gmail.com>, Jeevan Ladhe <jeevan.ladhe@enterprisedb.com>, Mark Dilger <mark.dilger@enterprisedb.com>, pgsql-hackers@postgresql.org, tushar <tushar.ahuja@enterprisedb.com>, Andres Freund <andres@anarazel.de>
Date: 2022-03-11T16:29:11Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Document BaseBackupSync and BaseBackupWrite wait events.

  2. Support long distance matching for zstd compression

  3. Fix possible NULL-pointer-deference in backup_compression.c.

  4. Allow parallel zstd compression when taking a base backup.

  5. Make PostgreSQL::Test::Cluster::run_log() return a useful value.

  6. Fix a few goofs in new backup compression code.

  7. Replace BASE_BACKUP COMPRESSION_LEVEL option with COMPRESSION_DETAIL.

  8. Add 'basebackup_to_shell' contrib module.

  9. Allow extensions to add new backup targets.

  10. Change HAVE_LIBLZ4 and HAVE_LIBZSTD tests to USE_LZ4 and USE_ZSTD.

  11. pg_basebackup: Clean up some bogus file extension tests.

  12. pg_basebackup: Avoid unclean failure with server-compression and -D -.

  13. Fix LZ4 tests for remaining buffer space.

  14. Add support for zstd base backup compression.

  15. pg_basebackup: Allow client-side LZ4 (de)compression.

  16. Add suport for server-side LZ4 base backup compression.

  17. Add min() and max() aggregates for xid8.

  18. Remove superfluous variable.

  19. pg_basebackup: Cleaner handling when compression is multiply specified.

  20. Allow server-side compression to be used with -Fp.

  21. pg_basebackup: Fix a couple of recently-introduced bugs.

  22. Tidy up a few cosmetic issues related to pg_basebackup.

  23. Server-side gzip compression.

  24. Unbreak pg_basebackup/t/010_pg_basebackup.pl on msys

  25. Suppress variable-set-but-not-used warning from clang 13.

  26. Extend the options of pg_basebackup to control compression

  27. Support base backup targets.

  28. Modify pg_basebackup to use a new COPY subprotocol for base backups.

  29. Document that tar archives are now properly terminated.

  30. Fix thinko in bbsink_throttle_manifest_contents.

  31. Have the server properly terminate tar archives.

  32. Minimal fix for unterminated tar archive problem.

  33. Introduce 'bbstreamer' abstraction to modularize pg_basebackup.

  34. Introduce 'bbsink' abstraction to modularize base backup code.

  35. Refactor basebackup.c's _tarWriteDir() function.

  36. Flexible options for CREATE_REPLICATION_SLOT.

  37. Flexible options for BASE_BACKUP.

On Fri, Mar 11, 2022 at 10:19:29AM -0500, Robert Haas wrote:
> So I think we should just refuse this command. Patch for that attached.

Sounds right.

Also, I think the magic 8 for .gz should actually be a 7.

I'm not sure why it tests for ".gz" but not ".tar.gz", which would help to make
them all less magic.

commit 1fb1e21ba7a500bb2b85ec3e65f59130fcdb4a7e
Author: Justin Pryzby <pryzbyj@telsasoft.com>
Date:   Thu Mar 10 21:22:16 2022 -0600

    pg_basebackup: make magic numbers less magic
    
    The magic 8 for .gz should actually be a 7.
    
    .tar.gz
    1234567
    
    .tar.lz4
    .tar.zst
    12345678
    
    See d45099425, 751b8d23b, 7cf085f07.

diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
index 9f3ecc60fbe..8dd9721323d 100644
--- a/src/bin/pg_basebackup/pg_basebackup.c
+++ b/src/bin/pg_basebackup/pg_basebackup.c
@@ -1223,17 +1223,17 @@ CreateBackupStreamer(char *archive_name, char *spclocation,
 	is_tar = (archive_name_len > 4 &&
 			  strcmp(archive_name + archive_name_len - 4, ".tar") == 0);
 
-	/* Is this a gzip archive? */
-	is_tar_gz = (archive_name_len > 8 &&
-				 strcmp(archive_name + archive_name_len - 3, ".gz") == 0);
+	/* Is this a .tar.gz archive? */
+	is_tar_gz = (archive_name_len > 7 &&
+				 strcmp(archive_name + archive_name_len - 7, ".tar.gz") == 0);
 
-	/* Is this a LZ4 archive? */
+	/* Is this a .tar.lz4 archive? */
 	is_tar_lz4 = (archive_name_len > 8 &&
-				  strcmp(archive_name + archive_name_len - 4, ".lz4") == 0);
+				  strcmp(archive_name + archive_name_len - 8, ".tar.lz4") == 0);
 
-	/* Is this a ZSTD archive? */
+	/* Is this a .tar.zst archive? */
 	is_tar_zstd = (archive_name_len > 8 &&
-				   strcmp(archive_name + archive_name_len - 4, ".zst") == 0);
+				   strcmp(archive_name + archive_name_len - 8, ".tar.zst") == 0);
 
 	/*
 	 * We have to parse the archive if (1) we're suppose to extract it, or if