Merge commit 'a39d4083cab589d7cd6a13e8a4b8db8875261d75'

[gnulib.git] / lib / lchown.c

diff --git a/lib/lchown.c b/lib/lchown.c
index 5bc7074..647b0a8 100644 (file)
--- a/lib/lchown.c
+++ b/lib/lchown.c
@@ -1,7 +1,7 @@
 /* Provide a stub lchown function for systems that lack it.
 
-   Copyright (C) 1998, 1999, 2002, 2004, 2006, 2007, 2009 Free
-   Software Foundation, Inc.
+   Copyright (C) 1998-1999, 2002, 2004, 2006-2007, 2009-2014 Free Software
+   Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -20,25 +20,20 @@
 
 #include <config.h>
 
-/* If the system chown does not follow symlinks, we don't want it
-   replaced by gnulib's chown, which does follow symlinks.  */
-#if CHOWN_MODIFIES_SYMLINK
-# define REPLACE_CHOWN 0
-#endif
 #include <unistd.h>
 
 #include <errno.h>
+#include <stdbool.h>
+#include <string.h>
 #include <sys/stat.h>
 
-/* Some systems don't have EOPNOTSUPP.  */
-#ifndef EOPNOTSUPP
-# ifdef ENOTSUP
-#  define EOPNOTSUPP ENOTSUP
-# else
-/* Some systems don't have ENOTSUP either.  */
-#  define EOPNOTSUPP EINVAL
+#if !HAVE_LCHOWN
+
+/* If the system chown does not follow symlinks, we don't want it
+   replaced by gnulib's chown, which does follow symlinks.  */
+# if CHOWN_MODIFIES_SYMLINK
+#  undef chown
 # endif
-#endif
 
 /* Work just like chown, except when FILE is a symbolic link.
    In that case, set errno to EOPNOTSUPP and return -1.
@@ -48,8 +43,8 @@
 int
 lchown (const char *file, uid_t uid, gid_t gid)
 {
-#if HAVE_CHOWN
-# if ! CHOWN_MODIFIES_SYMLINK
+# if HAVE_CHOWN
+#  if ! CHOWN_MODIFIES_SYMLINK
   struct stat stats;
 
   if (lstat (file, &stats) == 0 && S_ISLNK (stats.st_mode))
@@ -57,12 +52,66 @@ lchown (const char *file, uid_t uid, gid_t gid)
       errno = EOPNOTSUPP;
       return -1;
     }
-# endif
+#  endif
 
   return chown (file, uid, gid);
 
-#else /* !HAVE_CHOWN */
-  errno = EOPNOTSUPP;
+# else /* !HAVE_CHOWN */
+  errno = ENOSYS;
   return -1;
-#endif
+# endif
 }
+
+#else /* HAVE_LCHOWN */
+
+# undef lchown
+
+/* Work around trailing slash bugs in lchown.  */
+int
+rpl_lchown (const char *file, uid_t uid, gid_t gid)
+{
+  bool stat_valid = false;
+  int result;
+
+# if CHOWN_CHANGE_TIME_BUG
+  struct stat st;
+
+  if (gid != (gid_t) -1 || uid != (uid_t) -1)
+    {
+      if (lstat (file, &st))
+        return -1;
+      stat_valid = true;
+      if (!S_ISLNK (st.st_mode))
+        return chown (file, uid, gid);
+    }
+# endif
+
+# if CHOWN_TRAILING_SLASH_BUG
+  if (!stat_valid)
+    {
+      size_t len = strlen (file);
+      if (len && file[len - 1] == '/')
+        return chown (file, uid, gid);
+    }
+# endif
+
+  result = lchown (file, uid, gid);
+
+# if CHOWN_CHANGE_TIME_BUG && HAVE_LCHMOD
+  if (result == 0 && stat_valid
+      && (uid == st.st_uid || uid == (uid_t) -1)
+      && (gid == st.st_gid || gid == (gid_t) -1))
+    {
+      /* No change in ownership, but at least one argument was not -1,
+         so we are required to update ctime.  Since lchown succeeded,
+         we assume that lchmod will do likewise.  But if the system
+         lacks lchmod and lutimes, we are out of luck.  Oh well.  */
+      result = lchmod (file, st.st_mode & (S_IRWXU | S_IRWXG | S_IRWXO
+                                           | S_ISUID | S_ISGID | S_ISVTX));
+    }
+# endif
+
+  return result;
+}
+
+#endif /* HAVE_LCHOWN */