From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
---|---|
To: | pgsql-committers(at)postgresql(dot)org |
Subject: | pgsql: Fix miserable coding in pg_stat_get_activity(). |
Date: | 2016-09-10 17:49:16 |
Message-ID: | E1bimOy-000782-Ji@gemulon.postgresql.org |
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Lists: | pgsql-committers |
Fix miserable coding in pg_stat_get_activity().
Commit dd1a3bccc replaced a test on whether a subroutine returned a
null pointer with a test on whether &pointer->backendStatus was null.
This accidentally failed to fail, at least on common compilers, because
backendStatus is the first field in the struct; but it was surely trouble
waiting to happen. Commit f91feba87 then messed things up further,
changing the logic to
local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
if (!local_beentry)
continue;
beentry = &local_beentry->backendStatus;
if (!beentry)
{
where the second "if" is now dead code, so that the intended behavior of
printing a row with "<backend information not available>" cannot occur.
I suspect this is all moot because pgstat_fetch_stat_local_beentry
will never actually return null in this function's usage, but it's still
very poor coding. Repair back to 9.4 where the original problem was
introduced.
Branch
------
REL9_4_STABLE
Details
-------
http://git.postgresql.org/pg/commitdiff/fb7ed3889fa6fc0f4aa6718ffb6574801ad12484
Modified Files
--------------
src/backend/utils/adt/pgstatfuncs.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
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