Add support for the DIR_NLINK feature.

[tools/e2fsprogs.git] / lib / ext2fs / dirblock.c

diff --git a/lib/ext2fs/dirblock.c b/lib/ext2fs/dirblock.c
index 3d5dbb2..fb20fa0 100644 (file)
--- a/lib/ext2fs/dirblock.c
+++ b/lib/ext2fs/dirblock.c
@@ -1,75 +1,112 @@
 /*
  * dirblock.c --- directory block routines.
  * 
- * Copyright (C) 1995 Theodore Ts'o.  This file may be redistributed
- * under the terms of the GNU Public License.
+ * Copyright (C) 1995, 1996 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
  */
 
 #include <stdio.h>
+#if HAVE_UNISTD_H
 #include <unistd.h>
-#include <stdlib.h>
-#include <time.h>
-#ifdef HAVE_ERRNO_H
-#include <errno.h>
 #endif
+#include <string.h>
+#include <time.h>
 
-#include <linux/ext2_fs.h>
-
+#include "ext2_fs.h"
 #include "ext2fs.h"
 
-errcode_t ext2fs_read_dir_block(ext2_filsys fs, blk_t block,
-                               void *buf)
+errcode_t ext2fs_read_dir_block2(ext2_filsys fs, blk_t block,
+                                void *buf, int flags EXT2FS_ATTR((unused)))
 {
        errcode_t       retval;
        char            *p, *end;
        struct ext2_dir_entry *dirent;
+       unsigned int    name_len, rec_len;
+       
 
        retval = io_channel_read_blk(fs->io, block, 1, buf);
        if (retval)
                return retval;
-       if ((fs->flags & (EXT2_SWAP_BYTES|EXT2_SWAP_BYTES_READ)) == 0)
-               return 0;
-       p = buf;
+
+       p = (char *) buf;
        end = (char *) buf + fs->blocksize;
-       while (p < end) {
+       while (p < end-8) {
                dirent = (struct ext2_dir_entry *) p;
+#ifdef WORDS_BIGENDIAN
                dirent->inode = ext2fs_swab32(dirent->inode);
                dirent->rec_len = ext2fs_swab16(dirent->rec_len);
                dirent->name_len = ext2fs_swab16(dirent->name_len);
-               p += (dirent->rec_len < 8) ? 8 : dirent->rec_len;
+#endif
+               name_len = dirent->name_len;
+#ifdef WORDS_BIGENDIAN
+               if (flags & EXT2_DIRBLOCK_V2_STRUCT)
+                       dirent->name_len = ext2fs_swab16(dirent->name_len);
+#endif
+               rec_len = dirent->rec_len;
+               if ((rec_len < 8) || (rec_len % 4)) {
+                       rec_len = 8;
+                       retval = EXT2_ET_DIR_CORRUPTED;
+               }
+               if (((name_len & 0xFF) + 8) > dirent->rec_len)
+                       retval = EXT2_ET_DIR_CORRUPTED;
+               p += rec_len;
        }
-       return 0;
+       return retval;
 }
 
-errcode_t ext2fs_write_dir_block(ext2_filsys fs, blk_t block,
-                                void *inbuf)
+errcode_t ext2fs_read_dir_block(ext2_filsys fs, blk_t block,
+                                void *buf)
+{
+       return ext2fs_read_dir_block2(fs, block, buf, 0);
+}
+
+
+errcode_t ext2fs_write_dir_block2(ext2_filsys fs, blk_t block,
+                                 void *inbuf, int flags EXT2FS_ATTR((unused)))
 {
+#ifdef WORDS_BIGENDIAN
        errcode_t       retval;
-       char            *p, *end, *write_buf;
+       char            *p, *end;
        char            *buf = 0;
        struct ext2_dir_entry *dirent;
 
-       if ((fs->flags & EXT2_SWAP_BYTES) ||
-           (fs->flags & EXT2_SWAP_BYTES_WRITE)) {
-               write_buf = buf = malloc(fs->blocksize);
-               if (!buf)
-                       return ENOMEM;
-               memcpy(buf, inbuf, fs->blocksize);
-               p = buf;
-               end = buf + fs->blocksize;
-               while (p < end) {
-                       dirent = (struct ext2_dir_entry *) p;
-                       p += (dirent->rec_len < 8) ? 8 : dirent->rec_len;
-                       dirent->inode = ext2fs_swab32(dirent->inode);
-                       dirent->rec_len = ext2fs_swab16(dirent->rec_len);
-                       dirent->name_len = ext2fs_swab16(dirent->name_len);
+       retval = ext2fs_get_mem(fs->blocksize, &buf);
+       if (retval)
+               return retval;
+       memcpy(buf, inbuf, fs->blocksize);
+       p = buf;
+       end = buf + fs->blocksize;
+       while (p < end) {
+               dirent = (struct ext2_dir_entry *) p;
+               if ((dirent->rec_len < 8) ||
+                   (dirent->rec_len % 4)) {
+                       ext2fs_free_mem(&buf);
+                       return (EXT2_ET_DIR_CORRUPTED);
                }
-       } else
-               write_buf = inbuf;
-       retval = io_channel_write_blk(fs->io, block, 1, write_buf);
-       if (buf)
-               free(buf);
+               p += dirent->rec_len;
+               dirent->inode = ext2fs_swab32(dirent->inode);
+               dirent->rec_len = ext2fs_swab16(dirent->rec_len);
+               dirent->name_len = ext2fs_swab16(dirent->name_len);
+
+               if (flags & EXT2_DIRBLOCK_V2_STRUCT)
+                       dirent->name_len = ext2fs_swab16(dirent->name_len);
+       }
+       retval = io_channel_write_blk(fs->io, block, 1, buf);
+       ext2fs_free_mem(&buf);
        return retval;
+#else
+       return io_channel_write_blk(fs->io, block, 1, (char *) inbuf);
+#endif
 }
 
 
+errcode_t ext2fs_write_dir_block(ext2_filsys fs, blk_t block,
+                                void *inbuf)
+{
+       return ext2fs_write_dir_block2(fs, block, inbuf, 0);
+}
+