lib/ext2fs/dirblock.c

   1 /*
   2  * dirblock.c --- directory block routines.
   3  *
   4  * Copyright (C) 1995 Theodore Ts'o.  This file may be redistributed
   5  * under the terms of the GNU Public License.
   6  */
   7
   8 #include <stdio.h>
   9 #include <unistd.h>
  10 #include <stdlib.h>
  11 #include <time.h>
  12 #ifdef HAVE_ERRNO_H
  13 #include <errno.h>
  14 #endif
  15
  16 #include <linux/ext2_fs.h>
  17
  18 #include "ext2fs.h"
  19
  20 errcode_t ext2fs_read_dir_block(ext2_filsys fs, blk_t block,
  21                                 void *buf)
  22 {
  23         errcode_t       retval;
  24         char            *p, *end;
  25         struct ext2_dir_entry *dirent;
  26
  27         retval = io_channel_read_blk(fs->io, block, 1, buf);
  28         if (retval)
  29                 return retval;
  30         if ((fs->flags & EXT2_SWAP_BYTES) == 0)
  31                 return 0;
  32         p = buf;
  33         end = (char *) buf + fs->blocksize;
  34         while (p < end) {
  35                 dirent = (struct ext2_dir_entry *) p;
  36                 dirent->inode = ext2fs_swab32(dirent->inode);
  37                 dirent->rec_len = ext2fs_swab16(dirent->rec_len);
  38                 dirent->name_len = ext2fs_swab16(dirent->name_len);
  39                 p += (dirent->rec_len < 8) ? 8 : dirent->rec_len;
  40         }
  41         return 0;
  42 }
  43
  44 errcode_t ext2fs_write_dir_block(ext2_filsys fs, blk_t block,
  45                                  void *inbuf)
  46 {
  47         errcode_t       retval;
  48         char            *p, *end, *write_buf;
  49         char            *buf = 0;
  50         struct ext2_dir_entry *dirent;
  51
  52         if (fs->flags & EXT2_SWAP_BYTES) {
  53                 write_buf = buf = malloc(fs->blocksize);
  54                 if (!buf)
  55                         return ENOMEM;
  56                 memcpy(buf, inbuf, fs->blocksize);
  57                 p = buf;
  58                 end = buf + fs->blocksize;
  59                 while (p < end) {
  60                         dirent = (struct ext2_dir_entry *) p;
  61                         p += (dirent->rec_len < 8) ? 8 : dirent->rec_len;
  62                         dirent->inode = ext2fs_swab32(dirent->inode);
  63                         dirent->rec_len = ext2fs_swab16(dirent->rec_len);
  64                         dirent->name_len = ext2fs_swab16(dirent->name_len);
  65                 }
  66         } else
  67                 write_buf = inbuf;
  68         retval = io_channel_write_blk(fs->io, block, 1, write_buf);
  69         if (buf)
  70                 free(buf);
  71         return retval;
  72 }
  73
  74