diff options
| author | Tom Lane | 2022-09-27 15:47:12 +0000 |
|---|---|---|
| committer | Tom Lane | 2022-09-27 15:47:12 +0000 |
| commit | 385366426511399a91da327c0f04765bbcfd5322 (patch) | |
| tree | bb6851d6157032806a9df6ab23a4242b548bb378 /src/include/utils/guc.h | |
| parent | 4148c8b3daf95ca308f055e103f6ee82e25b8f99 (diff) | |
Introduce GUC_NO_RESET flag.
Previously, the transaction-property GUCs such as transaction_isolation
could be reset after starting a transaction, because we marked them
as GUC_NO_RESET_ALL but still allowed a targeted RESET. That leads to
assertion failures or worse, because those properties aren't supposed
to change after we've acquired a transaction snapshot.
There are some NO_RESET_ALL variables for which RESET is okay, so
we can't just redefine the semantics of that flag. Instead introduce
a separate GUC_NO_RESET flag. Mark "seed", as well as the transaction
property GUCs, as GUC_NO_RESET.
We have to disallow GUC_ACTION_SAVE as well as straight RESET, because
otherwise a function having a "SET transaction_isolation" clause can
still break things: the end-of-function restore action is equivalent
to a RESET.
No back-patch, as it's conceivable that someone is doing something
this patch will forbid (like resetting one of these GUCs at transaction
start, or "CREATE FUNCTION ... SET transaction_read_only = 1") and not
running into problems with it today. Given how long we've had this
issue and not noticed, the side effects in non-assert builds can't be
too serious.
Per bug #17385 from Andrew Bille.
Masahiko Sawada
Discussion: https://postgr.es/m/[email protected]
Diffstat (limited to 'src/include/utils/guc.h')
| -rw-r--r-- | src/include/utils/guc.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h index e426dd757d9..0fe86ba7041 100644 --- a/src/include/utils/guc.h +++ b/src/include/utils/guc.h @@ -207,6 +207,7 @@ typedef enum #define GUC_LIST_INPUT 0x0001 /* input can be list format */ #define GUC_LIST_QUOTE 0x0002 /* double-quote list elements */ #define GUC_NO_SHOW_ALL 0x0004 /* exclude from SHOW ALL */ +#define GUC_NO_RESET 0x400000 /* disallow RESET and SAVE */ #define GUC_NO_RESET_ALL 0x0008 /* exclude from RESET ALL */ #define GUC_REPORT 0x0010 /* auto-report changes to client */ #define GUC_NOT_IN_SAMPLE 0x0020 /* not in postgresql.conf.sample */ |