lib/ext2fs/dirblock.c

   1 /*
   2  * dirblock.c --- directory block routines.
   3  *
   4  * Copyright (C) 1995, 1996 Theodore Ts'o.
   5  *
   6  * %Begin-Header%
   7  * This file may be redistributed under the terms of the GNU Public
   8  * License.
   9  * %End-Header%
  10  */
  11
  12 #include <stdio.h>
  13 #if HAVE_UNISTD_H
  14 #include <unistd.h>
  15 #endif
  16 #include <stdlib.h>
  17 #include <string.h>
  18 #include <time.h>
  19
  20 #include <linux/ext2_fs.h>
  21
  22 #include "ext2fs.h"
  23
  24 errcode_t ext2fs_read_dir_block(ext2_filsys fs, blk_t block,
  25                                 void *buf)
  26 {
  27         errcode_t       retval;
  28         char            *p, *end;
  29         struct ext2_dir_entry *dirent;
  30
  31         retval = io_channel_read_blk(fs->io, block, 1, buf);
  32         if (retval)
  33                 return retval;
  34         if ((fs->flags & (EXT2_FLAG_SWAP_BYTES|
  35                           EXT2_FLAG_SWAP_BYTES_READ)) == 0)
  36                 return 0;
  37         p = buf;
  38         end = (char *) buf + fs->blocksize;
  39         while (p < end) {
  40                 dirent = (struct ext2_dir_entry *) p;
  41                 dirent->inode = ext2fs_swab32(dirent->inode);
  42                 dirent->rec_len = ext2fs_swab16(dirent->rec_len);
  43                 dirent->name_len = ext2fs_swab16(dirent->name_len);
  44                 p += (dirent->rec_len < 8) ? 8 : dirent->rec_len;
  45         }
  46         return 0;
  47 }
  48
  49 errcode_t ext2fs_write_dir_block(ext2_filsys fs, blk_t block,
  50                                  void *inbuf)
  51 {
  52         errcode_t       retval;
  53         char            *p, *end, *write_buf;
  54         char            *buf = 0;
  55         struct ext2_dir_entry *dirent;
  56
  57         if ((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
  58             (fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE)) {
  59                 write_buf = buf = malloc(fs->blocksize);
  60                 if (!buf)
  61                         return EXT2_NO_MEMORY;
  62                 memcpy(buf, inbuf, fs->blocksize);
  63                 p = buf;
  64                 end = buf + fs->blocksize;
  65                 while (p < end) {
  66                         dirent = (struct ext2_dir_entry *) p;
  67                         p += (dirent->rec_len < 8) ? 8 : dirent->rec_len;
  68                         dirent->inode = ext2fs_swab32(dirent->inode);
  69                         dirent->rec_len = ext2fs_swab16(dirent->rec_len);
  70                         dirent->name_len = ext2fs_swab16(dirent->name_len);
  71                 }
  72         } else
  73                 write_buf = inbuf;
  74         retval = io_channel_write_blk(fs->io, block, 1, write_buf);
  75         if (buf)
  76                 free(buf);
  77         return retval;
  78 }
  79
  80