(show_disk, show_point): If several filesystems are

mounted on the same mount point, prefer the last one, not the first.
Problem reported by Christian Jones in
<http://mail.gnu.org/archive/html/bug-coreutils/2004-04/msg00200.html>.
(show_disk): Remove unused statp arg.  Return bool, not int.
(show_point): Rewrite to avoid gotos.  Use the same algorithm
for lofs and dummies for each pass through the mount table,
rather than subtly different algorithms (which are probably
inadvertent).

diff --git a/src/df.c b/src/df.c
index e348f32536af66d3e2bc64739d9ae97b1b4e3407..40af136034014578c8ddd4ff23e82fdaae3b27c8 100644 (file)
--- a/src/df.c
+++ b/src/df.c
@@ -521,22 +521,26 @@ done:
 }
 
 /* If DISK corresponds to a mount point, show its usage
-   and return nonzero.  Otherwise, return zero.
-   STATP must be the result of `stat (DISK, STATP)'.  */
-static int
-show_disk (const char *disk, const struct stat *statp)
+   and return true.  Otherwise, return false.  */
+static bool
+show_disk (char const *disk)
 {
-  struct mount_entry *me;
+  struct mount_entry const *me;
+  struct mount_entry const *best_match = NULL;
 
   for (me = mount_list; me; me = me->me_next)
     if (STREQ (disk, me->me_devname))
-      {
-       show_dev (me->me_devname, me->me_mountdir, me->me_type,
-                 me->me_dummy, me->me_remote);
-       return 1;
-      }
+      best_match = me;
 
-  return 0;
+  if (best_match)
+    {
+      show_dev (best_match->me_devname, best_match->me_mountdir,
+               best_match->me_type, best_match->me_dummy,
+               best_match->me_remote);
+      return true;
+    }
+
+  return false;
 }
 
 /* Figure out which device file or directory POINT is mounted on
@@ -547,121 +551,104 @@ show_point (const char *point, const struct stat *statp)
 {
   struct stat disk_stats;
   struct mount_entry *me;
-  struct mount_entry *matching_dummy = NULL;
+  struct mount_entry const *best_match = NULL;
 
   /* If POINT is an absolute path name, see if we can find the
      mount point without performing any extra stat calls at all.  */
   if (*point == '/')
     {
-      for (me = mount_list; me; me = me->me_next)
-       {
-         if (STREQ (me->me_mountdir, point) && !STREQ (me->me_type, "lofs"))
-           {
-             /* Prefer non-dummy entries.  */
-             if (! me->me_dummy)
-               goto show_me;
-             matching_dummy = me;
-           }
-       }
+      /* Find the best match: prefer non-dummies, and then prefer the
+        last match if there are ties.  */
 
-      if (matching_dummy)
-       goto show_matching_dummy;
+      for (me = mount_list; me; me = me->me_next)
+       if (STREQ (me->me_mountdir, point) && !STREQ (me->me_type, "lofs")
+           && (!best_match || best_match->me_dummy || !me->me_dummy))
+         best_match = me;
     }
 
   /* Calculate the real absolute path for POINT, and use that to find
      the mount point.  This avoids statting unavailable mount points,
      which can hang df.  */
-  {
-    char *resolved = canonicalize_file_name (point);
-    ssize_t resolved_len = resolved ? strlen (resolved) : -1;
-    struct mount_entry *best_match = NULL;
+  if (! best_match)
+    {
+      char *resolved = canonicalize_file_name (point);
+      ssize_t resolved_len = resolved ? strlen (resolved) : -1;
 
-    if (1 <= resolved_len && resolved[0] == '/')
-      {
-       size_t best_match_len = 0;
+      if (1 <= resolved_len && resolved[0] == '/')
+       {
+         size_t best_match_len = 0;
 
-       for (me = mount_list; me; me = me->me_next)
-         if (! me->me_dummy)
-           {
-             size_t len = strlen (me->me_mountdir);
-             if (best_match_len < len && len <= resolved_len
-                 && (len == 1 /* root file system */
-                     || ((len == resolved_len || resolved[len] == '/')
-                         && strncmp (me->me_mountdir, resolved, len) == 0)))
-               {
-                 best_match = me;
-                 best_match_len = len;
-               }
-           }
-      }
+         for (me = mount_list; me; me = me->me_next)
+           if (!STREQ (me->me_type, "lofs")
+               && (!best_match || best_match->me_dummy || !me->me_dummy))
+             {
+               size_t len = strlen (me->me_mountdir);
+               if (best_match_len <= len && len <= resolved_len
+                   && (len == 1 /* root file system */
+                       || ((len == resolved_len || resolved[len] == '/')
+                           && strncmp (me->me_mountdir, resolved, len) == 0)))
+                 {
+                   best_match = me;
+                   best_match_len = len;
+                 }
+             }
+       }
 
-    if (resolved)
-      free (resolved);
+      if (resolved)
+       free (resolved);
 
-    if (best_match && !STREQ (best_match->me_type, "lofs")
-       && stat (best_match->me_mountdir, &disk_stats) == 0
-       && disk_stats.st_dev == statp->st_dev)
+      if (best_match
+         && (stat (best_match->me_mountdir, &disk_stats) != 0
+             || disk_stats.st_dev != statp->st_dev))
+       best_match = NULL;
+    }
+
+  if (! best_match)
+    for (me = mount_list; me; me = me->me_next)
       {
-       me = best_match;
-       goto show_me;
+       if (me->me_dev == (dev_t) -1)
+         {
+           if (stat (me->me_mountdir, &disk_stats) == 0)
+             me->me_dev = disk_stats.st_dev;
+           else
+             {
+               error (0, errno, "%s", quote (me->me_mountdir));
+               exit_status = 1;
+               /* So we won't try and fail repeatedly. */
+               me->me_dev = (dev_t) -2;
+             }
+         }
+
+       if (statp->st_dev == me->me_dev
+           && !STREQ (me->me_type, "lofs")
+           && (!best_match || best_match->me_dummy || !me->me_dummy))
+         {
+           /* Skip bogus mtab entries.  */
+           if (stat (me->me_mountdir, &disk_stats) != 0
+               || disk_stats.st_dev != me->me_dev)
+             me->me_dev = (dev_t) -2;
+           else
+             best_match = me;
+         }
       }
-  }
 
-  for (me = mount_list; me; me = me->me_next)
+  if (best_match)
+    show_dev (best_match->me_devname, best_match->me_mountdir,
+             best_match->me_type, best_match->me_dummy, best_match->me_remote);
+  else
     {
-      if (me->me_dev == (dev_t) -1)
-       {
-         if (stat (me->me_mountdir, &disk_stats) == 0)
-           me->me_dev = disk_stats.st_dev;
-         else
-           {
-             error (0, errno, "%s", quote (me->me_mountdir));
-             exit_status = 1;
-             /* So we won't try and fail repeatedly. */
-             me->me_dev = (dev_t) -2;
-           }
-       }
+      /* We couldn't find the mount entry corresponding to POINT.  Go ahead and
+        print as much info as we can; methods that require the device to be
+        present will fail at a later point.  */
 
-      if (statp->st_dev == me->me_dev)
+      /* Find the actual mount point.  */
+      char *mp = find_mount_point (point, statp);
+      if (mp)
        {
-         /* Skip bogus mtab entries.  */
-         if (stat (me->me_mountdir, &disk_stats) != 0
-             || disk_stats.st_dev != me->me_dev)
-           {
-             me->me_dev = (dev_t) -2;
-             continue;
-           }
-
-         /* Prefer non-dummy entries.  */
-         if (! me->me_dummy)
-           goto show_me;
-         matching_dummy = me;
+         show_dev (0, mp, 0, 0, 0);
+         free (mp);
        }
     }
-
-  if (matching_dummy)
-    goto show_matching_dummy;
-
-  /* We couldn't find the mount entry corresponding to POINT.  Go ahead and
-     print as much info as we can; methods that require the device to be
-     present will fail at a later point.  */
-  {
-    /* Find the actual mount point.  */
-    char *mp = find_mount_point (point, statp);
-    if (mp)
-      {
-       show_dev (0, mp, 0, 0, 0);
-       free (mp);
-      }
-  }
-
-  return;
-
- show_matching_dummy:
-  me = matching_dummy;
- show_me:
-  show_dev (me->me_devname, me->me_mountdir, me->me_type, me->me_dummy,
-           me->me_remote);
 }
 
 /* Determine what kind of node PATH is and show the disk usage
@@ -671,7 +658,7 @@ static void
 show_entry (const char *path, const struct stat *statp)
 {
   if ((S_ISBLK (statp->st_mode) || S_ISCHR (statp->st_mode))
-      && show_disk (path, statp))
+      && show_disk (path))
     return;
 
   show_point (path, statp);