new function qset_acl

[Paul Eggert]

I needed a function that acts like set_acl but has syscall semantics
rather than invoking 'error' on failure.

Come to think of it, it might be better for the acl functions to
consistently have syscall semantics.  That would be an incompatible
change, though.  For now, I installed just the following patch, which
is upwards compatible (except that it uses more-consistent diagnostics
when set_acl fails).

2007-11-28  Paul Eggert  <address@hidden>

        New function qset_acl, like set_acl but with syscall semantics.
        * lib/acl.h (qset_acl): New decl.
        * lib/acl.c (qset_acl): New function.
        (set_acl): Use new function.  Use more-consistent diagnostics.

diff --git a/lib/acl.c b/lib/acl.c
index 89d48d3..5214c51 100644
--- a/lib/acl.c
+++ b/lib/acl.c
@@ -40,11 +40,11 @@ chmod_or_fchmod (const char *name, int desc, mode_t mode)
 /* Copy access control lists from one file to another. If SOURCE_DESC is
    a valid file descriptor, use file descriptor operations, else use
    filename based operations on SRC_NAME. Likewise for DEST_DESC and
-   DEST_NAME.
+   DST_NAME.
    If access control lists are not available, fchmod the target file to
    MODE.  Also sets the non-permission bits of the destination file
    (S_ISUID, S_ISGID, S_ISVTX) to those from MODE if any are set.
-   System call return value semantics.  */
+   Return 0 if successful, otherwise output a diagnostic and return -1.  */

 int
 copy_acl (const char *src_name, int source_desc, const char *dst_name,
@@ -161,7 +161,7 @@ copy_acl (const char *src_name, int source_desc, const char 
*dst_name,
    semantics.  */

 int
-set_acl (char const *name, int desc, mode_t mode)
+qset_acl (char const *name, int desc, mode_t mode)
 {
 #if USE_ACL && HAVE_ACL_SET_FILE && HAVE_ACL_FREE
   /* POSIX 1003.1e draft 17 (abandoned) specific version.  */
@@ -185,10 +185,7 @@ set_acl (char const *name, int desc, mode_t mode)
     {
       acl = acl_from_mode (mode);
       if (!acl)
-       {
-         error (0, errno, "%s", quote (name));
-         return -1;
-       }
+       return -1;
     }
   else
     {
@@ -206,10 +203,7 @@ set_acl (char const *name, int desc, mode_t mode)

       acl = acl_from_text (acl_text);
       if (!acl)
-       {
-         error (0, errno, "%s", quote (name));
-         return -1;
-       }
+       return -1;
     }
   if (HAVE_ACL_SET_FD && desc != -1)
     ret = acl_set_fd (desc, acl);
@@ -227,17 +221,14 @@ set_acl (char const *name, int desc, mode_t mode)
          else
            return 0;
        }
-      error (0, saved_errno, _("setting permissions for %s"), quote (name));
+      errno = saved_errno;
       return -1;
     }
   else
     acl_free (acl);

   if (S_ISDIR (mode) && acl_delete_def_file (name))
-    {
-      error (0, errno, _("setting permissions for %s"), quote (name));
-      return -1;
-    }
+    return -1;

   if (mode & (S_ISUID | S_ISGID | S_ISVTX))
     {
@@ -245,16 +236,21 @@ set_acl (char const *name, int desc, mode_t mode)
          been set.  */

       if (chmod_or_fchmod (name, desc, mode))
-       {
-         error (0, errno, _("preserving permissions for %s"), quote (name));
-         return -1;
-       }
+       return -1;
     }
   return 0;
 #else
-   int ret = chmod_or_fchmod (name, desc, mode);
-   if (ret)
-     error (0, errno, _("setting permissions for %s"), quote (name));
-   return ret;
+  return chmod_or_fchmod (name, desc, mode);
 #endif
 }
+
+/* As with qset_acl, but also output a diagnostic on failure.  */
+
+int
+set_acl (char const *name, int desc, mode_t mode)
+{
+  int r = qset_acl (name, desc, mode);
+  if (r != 0)
+    error (0, errno, _("setting permissions for %s"), quote (name));
+  return r;
+}
diff --git a/lib/acl.h b/lib/acl.h
index 34a7883..00cc60d 100644
--- a/lib/acl.h
+++ b/lib/acl.h
@@ -31,4 +31,5 @@
 int file_has_acl (char const *, struct stat const *);
 int copy_acl (char const *, int, char const *, int, mode_t);
 int set_acl (char const *, int, mode_t);
+int qset_acl (char const *, int, mode_t);
 int chmod_or_fchmod (char const *, int, mode_t);