dblink/isolationtester/fe_utils: Use new cancel API

Commit 61461a300c1c introduced new functions to libpq for cancelling
queries.  This replaces the usage of the old ones in parts of the
codebase with these newer ones.  This specifically leaves out changes to
psql and pgbench, as those would need a much larger refactor to be able
to call them due to the new functions not being signal-safe; and also
postgres_fdw, because the original code there is not clear to me
(Álvaro) and not fully tested.

Author: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: https://postgr.es/m/CAGECzQT_VgOWWENUqvUV9xQmbaCyXjtRRAYO8W07oqashk_N+g@mail.gmail.com

1 files changed, 3 insertions, 8 deletions

diff --git a/src/fe_utils/connect_utils.c b/src/fe_utils/connect_utils.c
index 808d54461fd..5ed9f3ba17b 100644
--- a/src/fe_utils/connect_utils.c
+++ b/src/fe_utils/connect_utils.c
@@ -157,19 +157,14 @@ connectMaintenanceDatabase(ConnParams *cparams,
 void
 disconnectDatabase(PGconn *conn)
 {
-	char		errbuf[256];
-
 	Assert(conn != NULL);
 
 	if (PQtransactionStatus(conn) == PQTRANS_ACTIVE)
 	{
-		PGcancel   *cancel;
+		PGcancelConn *cancelConn = PQcancelCreate(conn);
 
-		if ((cancel = PQgetCancel(conn)))
-		{
-			(void) PQcancel(cancel, errbuf, sizeof(errbuf));
-			PQfreeCancel(cancel);
-		}
+		(void) PQcancelBlocking(cancelConn);
+		PQcancelFinish(cancelConn);
 	}
 
 	PQfinish(conn);