debugfs: optimize ncheck and improve its error checking

Don't call ext2fs_get_pathname() for every single directory; instead,
only call it if we find a matching directory entry.  In addition, if
ext2fs_get_pathname() fails, print the number of the parent directory
in angle parents so the user gets some additional information.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/debugfs/ncheck.c b/debugfs/ncheck.c
index 739e001..09b844c 100644 (file)
--- a/debugfs/ncheck.c
+++ b/debugfs/ncheck.c
@@ -20,11 +20,13 @@
 #include "debugfs.h"
 
 struct inode_walk_struct {
+       ext2_ino_t              dir;
        ext2_ino_t              *iarray;
        int                     inodes_left;
        int                     num_inodes;
        int                     position;
        char                    *parent;
+       unsigned int            get_pathname_failed;
 };
 
 static int ncheck_proc(struct ext2_dir_entry *dirent,
@@ -34,15 +36,32 @@ static int ncheck_proc(struct ext2_dir_entry *dirent,
                       void     *private)
 {
        struct inode_walk_struct *iw = (struct inode_walk_struct *) private;
-       int     i;
+       errcode_t       retval;
+       int             i;
 
        iw->position++;
        if (iw->position <= 2)
                return 0;
        for (i=0; i < iw->num_inodes; i++) {
                if (iw->iarray[i] == dirent->inode) {
-                       printf("%u\t%s/%.*s\n", iw->iarray[i], iw->parent,
-                              (dirent->name_len & 0xFF), dirent->name);
+                       if (!iw->parent && !iw->get_pathname_failed) {
+                               retval = ext2fs_get_pathname(current_fs,
+                                                            iw->dir,
+                                                            0, &iw->parent);
+                               if (retval) {
+                                       com_err("ncheck", retval,
+               "while calling ext2fs_get_pathname for inode #%u", iw->dir);
+                                       iw->get_pathname_failed = 1;
+                               }
+                       }
+                       if (iw->parent)
+                               printf("%u\t%s/%.*s\n", iw->iarray[i],
+                                      iw->parent,
+                                      (dirent->name_len & 0xFF), dirent->name);
+                       else
+                               printf("%u\t<%u>/%.*s\n", iw->iarray[i],
+                                      iw->dir,
+                                      (dirent->name_len & 0xFF), dirent->name);
                }
        }
        if (!iw->inodes_left)
@@ -115,13 +134,9 @@ void do_ncheck(int argc, char **argv)
                        goto next;
 
                iw.position = 0;
-
-               retval = ext2fs_get_pathname(current_fs, ino, 0, &iw.parent);
-               if (retval) {
-                       com_err("ncheck", retval, 
-                               "while calling ext2fs_get_pathname");
-                       goto next;
-               }
+               iw.parent = 0;
+               iw.dir = ino;
+               iw.get_pathname_failed = 0;
 
                retval = ext2fs_dir_iterate(current_fs, ino, 0, 0,
                                            ncheck_proc, &iw);