Horton

RE: [HACKERS] logical decoding of two-phase transactions

wangsh.fnst@fujitsu.com <wangsh.fnst@fujitsu.com>

View thread View on postgr.es
From: "wangsh.fnst@fujitsu.com" <wangsh.fnst@fujitsu.com>
To: 'Peter Smith' <smithpb2250@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@postgresql.org>, "osumi.takamichi@fujitsu.com" <osumi.takamichi@fujitsu.com>, vignesh C <vignesh21@gmail.com>
Date: 2021-03-14T02:52:05Z
Lists: pgsql-hackers 
Hi, 

I noticed in patch v58-0001-Add-support-for-apply-at-prepare-time-to-built-i.patch

> +static void
> +prepare_spoolfile_name(char *path, int szpath, Oid subid, char *gid)
> +{
> +	PsfHashEntry *hentry;
> +
> +	/*
> +	 * This name is used as the key in the psf_hash HTAB. Therefore, the name
> +	 * and the key must be exactly same lengths and padded with '\0' so
> +	 * garbage does not impact the HTAB lookups.
> +	 */
> +	Assert(sizeof(hentry->name) == MAXPGPATH);
> +	Assert(szpath == MAXPGPATH);
> +	memset(path, '\0', MAXPGPATH);
> +
> +	snprintf(path, MAXPGPATH, "%s/psf_%u_%s.changes", PSF_DIR, subid, gid);
> +}

The variable hentry is only used when --enable-cassert is specified, it will be a warning if I don't specify the 
--enable-cassert when execute configure

And the comment says the lengths are same, I think ' Assert(sizeof(hentry->name) == szpath) ' will be better.

Best regards.
Shenhao Wang

Commits

  1. Add prepare API support for streaming transactions in logical replication.

  2. Doc: minor improvements for logical replication protocol documentation.

  3. Fix test failure in 021_twophase.pl.

  4. Refactor to make common functions in proto.c and worker.c.

  5. Unify PostgresNode's new() and get_new_node() methods

  6. Fix potential buffer overruns in proto.c.

  7. Add support for prepared transactions to built-in logical replication.

  8. Refactor function parse_subscription_options.

  9. Allow enabling two-phase option via replication protocol.

  10. Don't use Asserts to check for violations of replication protocol.

  11. Improve psql tab completion for options of subcriptions and publications

  12. Rearrange logrep worker's snapshot handling some more.

  13. doc: Update information of new messages for logical replication.

  14. ALTER SUBSCRIPTION ... ADD/DROP PUBLICATION

  15. Allow pgoutput to send logical decoding messages.

  16. Refactor function parse_output_parameters.

  17. Avoid repeated decoding of prepared transactions after a restart.

  18. Fix an oversight in ReorderBufferFinishPrepared.

  19. Allow multiple xacts during table sync in logical replication.

  20. Fix replication of in-progress transactions in tablesync worker.

  21. Fix 'skip-empty-xacts' option in test_decoding for streaming mode.

  22. Use Enum for top level logical replication message types.

  23. Add support for streaming to built-in logical replication.

  24. Fix the logical streaming test.

  25. Implement streaming mode in ReorderBuffer.

  26. Extend the logical decoding output plugin API with stream methods.

  27. Store 2PC GID in commit/abort WAL recs for logical decoding