From a11bce64a3be38f726cdca682f1e5b723cfd34d1 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathan@postgresql.org>
Date: Fri, 11 Sep 2026 15:18:40 -0500
Subject: [PATCH] Fix option argument lookup in in-tree getopt_long().

The in-tree getopt_long() moves each non-option to the end of argv,
which might put it right where an option's argument lookup expects
to find the argument.  For example, "vacuumdb postgres --jobs"
takes "postgres" as the number of jobs instead of complaining that
--jobs is missing its argument.  To fix, stop the argument lookups
at the start of the moved non-options, which we already track to
know when to stop scanning.

Oversight in commit 411b720343.

Author: Sehrope Sarkuni <sehrope@jackdb.com>
Reviewed-by: solai v <solai.cdac@gmail.com>
Discussion: https://postgr.es/m/CAH7T-arxDuVCSkorO%3Dk7%2BM-_JV0JFzMpN_EtKMyD2K0RDqZ2OA%40mail.gmail.com
Backpatch-through: 17
---
 src/bin/scripts/t/100_vacuumdb.pl |  4 ++++
 src/port/getopt_long.c            | 14 +++++++-------
 2 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/src/bin/scripts/t/100_vacuumdb.pl b/src/bin/scripts/t/100_vacuumdb.pl
index 1a2bcb49591..92a50eacab0 100644
--- a/src/bin/scripts/t/100_vacuumdb.pl
+++ b/src/bin/scripts/t/100_vacuumdb.pl
@@ -207,5 +207,9 @@ $node->command_fails_like(
 	[ 'vacuumdb', '-a', 'postgres' ],
 	qr/cannot vacuum all databases and a specific one at the same time/,
 	'cannot use option -a and a dbname as argument at the same time');
+$node->command_fails_like(
+	[ 'vacuumdb', 'postgres', '--jobs' ],
+	qr/requires an argument/,
+	'option missing its argument after a non-option');
 
 done_testing();
diff --git a/src/port/getopt_long.c b/src/port/getopt_long.c
index 20953db9db1..3b5d27e9cee 100644
--- a/src/port/getopt_long.c
+++ b/src/port/getopt_long.c
@@ -66,6 +66,9 @@ getopt_long(int argc, char *const argv[],
 	static int	nonopt_start = -1;
 	static bool force_nonopt = false;
 
+	if (nonopt_start == -1)
+		nonopt_start = argc;
+
 	if (!*place)
 	{							/* update scanning pointer */
 		char	  **args = (char **) argv;
@@ -75,7 +78,7 @@ retry:
 		/*
 		 * If we are out of arguments or only non-options remain, return -1.
 		 */
-		if (optind >= argc || optind == nonopt_start)
+		if (optind >= nonopt_start)
 		{
 			place = EMSG;
 			nonopt_start = -1;
@@ -99,10 +102,7 @@ retry:
 				args[i] = args[i + 1];
 			args[argc - 1] = place;
 
-			if (nonopt_start == -1)
-				nonopt_start = argc - 1;
-			else
-				nonopt_start--;
+			nonopt_start--;
 
 			goto retry;
 		}
@@ -137,7 +137,7 @@ retry:
 					{
 						if (place[namelen] == '=')
 							optarg = place + namelen + 1;
-						else if (optind < argc - 1 &&
+						else if (optind < nonopt_start - 1 &&
 								 has_arg == required_argument)
 						{
 							optind++;
@@ -220,7 +220,7 @@ retry:
 	{							/* need an argument */
 		if (*place)				/* no white space */
 			optarg = place;
-		else if (argc <= ++optind)
+		else if (nonopt_start <= ++optind)
 		{						/* no arg */
 			place = EMSG;
 			if (*optstring == ':')