From: Bruno Haible <bruno@clisp.org>
Date: Thu, 14 Aug 2025 19:54:44 +0000 (+0200)
Subject: chown: Use issymlink.
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3cbc197fcf04a6c0982aceb3cdc3edc80e34727a;p=thirdparty%2Fgnulib.git

chown: Use issymlink.

* lib/chown.c (rpl_chown): Use issymlink instead of readlink.
* modules/chown (Depends-on): Add issymlink.
---

diff --git a/ChangeLog b/ChangeLog
index 09afcc04c6..4e387893cb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2025-08-14  Bruno Haible  <bruno@clisp.org>
+
+	chown: Use issymlink.
+	* lib/chown.c (rpl_chown): Use issymlink instead of readlink.
+	* modules/chown (Depends-on): Add issymlink.
+
 2025-08-14  Bruno Haible  <bruno@clisp.org>
 
 	issymlink, issymlinkat: New modules.
diff --git a/lib/chown.c b/lib/chown.c
index 6cfc7e52b8..2ad9972100 100644
--- a/lib/chown.c
+++ b/lib/chown.c
@@ -87,8 +87,7 @@ rpl_chown (const char *file, uid_t uid, gid_t gid)
      If the file is a symlink, open the file (following symlinks), and
      fchown the resulting descriptor.  Although the open might fail
      due to lack of permissions, it's the best we can easily do.  */
-  char linkbuf[1];
-  if (0 <= readlink (file, linkbuf, sizeof linkbuf))
+  if (issymlink (file) > 0)
     {
       int open_flags = O_NONBLOCK | O_NOCTTY | O_CLOEXEC;
       int fd = open (file, O_RDONLY | open_flags);
diff --git a/modules/chown b/modules/chown
index 7fe9ebfecf..b1aedde85c 100644
--- a/modules/chown
+++ b/modules/chown
@@ -9,6 +9,7 @@ m4/chown.m4
 Depends-on:
 unistd-h
 fstat           [test $HAVE_CHOWN = 0 || test $REPLACE_CHOWN = 1]
+issymlink       [test $HAVE_CHOWN = 0 || test $REPLACE_CHOWN = 1]
 open            [test $HAVE_CHOWN = 0 || test $REPLACE_CHOWN = 1]
 stat            [test $HAVE_CHOWN = 0 || test $REPLACE_CHOWN = 1]
 bool            [test $HAVE_CHOWN = 0 || test $REPLACE_CHOWN = 1]