isolationtester: Use atexit()

Replace exit_nicely() calls with standard exit() and register the
cleanup actions using atexit().
Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/ec4135ba-84e9-28bf-b584-0e78d47448d5@2ndquadrant.com/

src/test/isolation/isolationtester.c

@@ -32,7 +32,6 @@ static int	nconns = 0;
 /* In dry run only output permutations to be run by the tester. */
 static int	dry_run = false;
 
-static void exit_nicely(void) pg_attribute_noreturn();
 static void run_testspec(TestSpec *testspec);
 static void run_all_permutations(TestSpec *testspec);
 static void run_all_permutations_recurse(TestSpec *testspec, int nsteps,
@@ -51,15 +50,14 @@ static void printResultSet(PGresult *res);
 static void isotesterNoticeProcessor(void *arg, const char *message);
 static void blackholeNoticeProcessor(void *arg, const char *message);
 
-/* close all connections and exit */
 static void
-exit_nicely(void)
+disconnect_atexit(void)
 {
 	int			i;
 
 	for (i = 0; i < nconns; i++)
+		if (conns[i])
 			PQfinish(conns[i]);
-	exit(1);
 }
 
 int
@@ -140,7 +138,7 @@ main(int argc, char **argv)
 		{
 			fprintf(stderr, "duplicate step name: %s\n",
 					testspec->allsteps[i]->name);
-			exit_nicely();
+			exit(1);
 		}
 	}
 
@@ -162,6 +160,7 @@ main(int argc, char **argv)
 	 */
 	nconns = 1 + testspec->nsessions;
 	conns = calloc(nconns, sizeof(PGconn *));
+	atexit(disconnect_atexit);
 	backend_pids = calloc(nconns, sizeof(*backend_pids));
 	for (i = 0; i < nconns; i++)
 	{
@@ -170,7 +169,7 @@ main(int argc, char **argv)
 		{
 			fprintf(stderr, "Connection %d to database failed: %s",
 					i, PQerrorMessage(conns[i]));
-			exit_nicely();
+			exit(1);
 		}
 
 		/*
@@ -196,7 +195,7 @@ main(int argc, char **argv)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			fprintf(stderr, "message level setup failed: %s", PQerrorMessage(conns[i]));
-			exit_nicely();
+			exit(1);
 		}
 		PQclear(res);
 
@@ -210,14 +209,14 @@ main(int argc, char **argv)
 			{
 				fprintf(stderr, "backend pid query returned %d rows and %d columns, expected 1 row and 1 column",
 						PQntuples(res), PQnfields(res));
-				exit_nicely();
+				exit(1);
 			}
 		}
 		else
 		{
 			fprintf(stderr, "backend pid query failed: %s",
 					PQerrorMessage(conns[i]));
-			exit_nicely();
+			exit(1);
 		}
 		PQclear(res);
 	}
@@ -254,7 +253,7 @@ main(int argc, char **argv)
 	{
 		fprintf(stderr, "prepare of lock wait query failed: %s",
 				PQerrorMessage(conns[0]));
-		exit_nicely();
+		exit(1);
 	}
 	PQclear(res);
 	termPQExpBuffer(&wait_query);
@@ -265,9 +264,6 @@ main(int argc, char **argv)
 	 */
 	run_testspec(testspec);
 
-	/* Clean up and exit */
-	for (i = 0; i < nconns; i++)
-		PQfinish(conns[i]);
 	return 0;
 }
 
@@ -375,7 +371,7 @@ run_named_permutations(TestSpec *testspec)
 			{
 				fprintf(stderr, "undefined step \"%s\" specified in permutation\n",
 						p->stepnames[j]);
-				exit_nicely();
+				exit(1);
 			}
 			steps[j] = *this;
 		}
@@ -510,7 +506,7 @@ run_permutation(TestSpec *testspec, int nsteps, Step **steps)
 		else if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			fprintf(stderr, "setup failed: %s", PQerrorMessage(conns[0]));
-			exit_nicely();
+			exit(1);
 		}
 		PQclear(res);
 	}
@@ -530,7 +526,7 @@ run_permutation(TestSpec *testspec, int nsteps, Step **steps)
 				fprintf(stderr, "setup of session %s failed: %s",
 						testspec->sessions[i]->name,
 						PQerrorMessage(conns[i + 1]));
-				exit_nicely();
+				exit(1);
 			}
 			PQclear(res);
 		}
@@ -612,7 +608,7 @@ run_permutation(TestSpec *testspec, int nsteps, Step **steps)
 		{
 			fprintf(stdout, "failed to send query for step %s: %s\n",
 					step->name, PQerrorMessage(conn));
-			exit_nicely();
+			exit(1);
 		}
 
 		/* Try to complete this step without blocking.  */
@@ -723,7 +719,7 @@ try_complete_step(Step *step, int flags)
 	if (sock < 0)
 	{
 		fprintf(stderr, "invalid socket: %s", PQerrorMessage(conn));
-		exit_nicely();
+		exit(1);
 	}
 
 	gettimeofday(&start_time, NULL);
@@ -741,7 +737,7 @@ try_complete_step(Step *step, int flags)
 			if (errno == EINTR)
 				continue;
 			fprintf(stderr, "select failed: %s\n", strerror(errno));
-			exit_nicely();
+			exit(1);
 		}
 		else if (ret == 0)		/* select() timeout: check for lock wait */
 		{
@@ -761,7 +757,7 @@ try_complete_step(Step *step, int flags)
 				{
 					fprintf(stderr, "lock wait query failed: %s",
 							PQerrorMessage(conns[0]));
-					exit_nicely();
+					exit(1);
 				}
 				waiting = ((PQgetvalue(res, 0, 0))[0] == 't');
 				PQclear(res);
@@ -818,14 +814,14 @@ try_complete_step(Step *step, int flags)
 			{
 				fprintf(stderr, "step %s timed out after 200 seconds\n",
 						step->name);
-				exit_nicely();
+				exit(1);
 			}
 		}
 		else if (!PQconsumeInput(conn)) /* select(): data available */
 		{
 			fprintf(stderr, "PQconsumeInput failed: %s\n",
 					PQerrorMessage(conn));
-			exit_nicely();
+			exit(1);
 		}
 	}