From 5db0d046b65a464f9be3560ab4eb298cd30864a1 Mon Sep 17 00:00:00 2001
From: Daniel Shahaf <d.s@daniel.shahaf.name>
Date: Wed, 14 May 2025 14:52:41 +0000
Subject: [PATCH] 53607: Stop printing /usr/bin/foo -> /usr/bin/foo in 'whence
 -s'.

Makes the new test PASS.

Review-by: Bart Schaefer
---
 ChangeLog           |  3 +++
 Src/utils.c         | 14 +++++++++++++-
 Test/B13whence.ztst |  2 +-
 configure.ac        |  1 +
 4 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index cd370cb09..6e7f96f41 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
 2025-05-14  Daniel Shahaf  <d.s@daniel.shahaf.name>
 
+	* 53607: Src/utils.c, Test/B13whence.ztst: Stop printing
+	/usr/bin/foo -> /usr/bin/foo in 'whence -s'.
+
 	* 53524 (cf. 53607): Test/B13whence.ztst: Add an XFAIL test for a
 	'whence -s' bug involving non-symlink arguments.
 
diff --git a/Src/utils.c b/Src/utils.c
index 19fd61a8b..4ea7b8e93 100644
--- a/Src/utils.c
+++ b/Src/utils.c
@@ -1003,11 +1003,23 @@ print_if_link(char *s, int all)
 		}
 	    }
 	} else {
-	    if (chrealpath(&s, 'P', 0)) {
+#ifdef HAVE_MEMCCPY
+	    char s_at_entry[PATH_MAX+1];
+	    if (!memccpy(s_at_entry, s, '\0', sizeof(s_at_entry))) {
+		DPUTS1(1, "path longer than PATH_MAX: %s", s);
+		s_at_entry[PATH_MAX] = '\0';
+	    }
+#else /* HAVE_MEMCCPY */
+	    char *s_at_entry = ztrdup(s);
+#endif /* HAVE_MEMCCPY */
+	    if (chrealpath(&s, 'P', 0) && strcmp(s, s_at_entry)) {
 		printf(" -> ");
 		zputs(*s ? s : "/", stdout);
 		zsfree(s);
 	    }
+#ifndef HAVE_MEMCCPY
+	    zsfree(s_at_entry);
+#endif /* !HAVE_MEMCCPY */
 	}
     }
 }
diff --git a/Test/B13whence.ztst b/Test/B13whence.ztst
index e455d38ae..5132c2c04 100644
--- a/Test/B13whence.ztst
+++ b/Test/B13whence.ztst
@@ -34,5 +34,5 @@
 1:whence deals with symlink loops gracefully
 
  whence -s =sh(:P) | grep '.->' | wc -l
--fD:(workers/53524) whence -s doesn't print arrows for symlink-free paths
+0:(workers/53524) whence -s doesn't print arrows for symlink-free paths
 >0
diff --git a/configure.ac b/configure.ac
index ab368c9a7..13895bb1d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1261,6 +1261,7 @@ AC_CHECK_FUNCS(strftime strptime mktime timelocal \
 	       initgroups \
 	       setuid seteuid setreuid setresuid setsid \
 	       setgid setegid setregid setresgid \
+	       memccpy \
 	       memcpy memmove strstr strerror strtoul \
 	       getrlimit getrusage \
 	       setlocale \