dblink, postgres_fdw: Handle interrupts during connection establishment
Until now dblink and postgres_fdw did not process interrupts during connection
establishment. Besides preventing query cancellations etc, this can lead to
undetected deadlocks, as global barriers are not processed.
These aforementioned undetected deadlocks are the reason for the spate of CI
test failures in the FreeBSD 'test_running' step.
Fix the bug by using the helper from libpq-be-fe-helpers.h, introduced in a
prior commit. Besides fixing the bug, this also removes duplicated code
around reserving file descriptors.
As the change is relatively large and there are no field reports of the
problem, don't backpatch for now.
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/20220925232237.p6uskba2dw6fnwj2@awork3.anarazel.de
Backpatch:
Branch
------
master
Details
-------
https://git.postgresql.org/pg/commitdiff/e4602483e95bebd4da31e4ea95dc5c7f715c1e4f
Modified Files
--------------
contrib/dblink/dblink.c | 79 ++++++---------------------------------
contrib/postgres_fdw/connection.c | 42 +++------------------
2 files changed, 17 insertions(+), 104 deletions(-)