1 | /*
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2 | * ind_block.c --- indirect block I/O routines
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3 | *
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4 | * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
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5 | * 2001, 2002, 2003, 2004, 2005 by Theodore Ts'o.
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6 | *
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7 | * %Begin-Header%
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8 | * This file may be redistributed under the terms of the GNU Public
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9 | * License.
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10 | * %End-Header%
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11 | */
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12 |
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13 | #include <stdio.h>
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14 | #include <string.h>
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15 | #if HAVE_UNISTD_H
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16 | #include <unistd.h>
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17 | #endif
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18 |
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19 | #include "ext2_fs.h"
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20 | #include "ext2fs.h"
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21 |
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22 | errcode_t ext2fs_read_ind_block(ext2_filsys fs, blk_t blk, void *buf)
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23 | {
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24 | errcode_t retval;
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25 | #if BB_BIG_ENDIAN
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26 | blk_t *block_nr;
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27 | int i;
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28 | int limit = fs->blocksize >> 2;
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29 | #endif
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30 |
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31 | if ((fs->flags & EXT2_FLAG_IMAGE_FILE) &&
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32 | (fs->io != fs->image_io))
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33 | memset(buf, 0, fs->blocksize);
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34 | else {
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35 | retval = io_channel_read_blk(fs->io, blk, 1, buf);
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36 | if (retval)
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37 | return retval;
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38 | }
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39 | #if BB_BIG_ENDIAN
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40 | if (fs->flags & (EXT2_FLAG_SWAP_BYTES | EXT2_FLAG_SWAP_BYTES_READ)) {
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41 | block_nr = (blk_t *) buf;
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42 | for (i = 0; i < limit; i++, block_nr++)
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43 | *block_nr = ext2fs_swab32(*block_nr);
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44 | }
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45 | #endif
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46 | return 0;
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47 | }
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48 |
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49 | errcode_t ext2fs_write_ind_block(ext2_filsys fs, blk_t blk, void *buf)
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50 | {
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51 | #if BB_BIG_ENDIAN
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52 | blk_t *block_nr;
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53 | int i;
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54 | int limit = fs->blocksize >> 2;
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55 | #endif
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56 |
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57 | if (fs->flags & EXT2_FLAG_IMAGE_FILE)
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58 | return 0;
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59 |
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60 | #if BB_BIG_ENDIAN
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61 | if (fs->flags & (EXT2_FLAG_SWAP_BYTES | EXT2_FLAG_SWAP_BYTES_WRITE)) {
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62 | block_nr = (blk_t *) buf;
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63 | for (i = 0; i < limit; i++, block_nr++)
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64 | *block_nr = ext2fs_swab32(*block_nr);
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65 | }
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66 | #endif
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67 | return io_channel_write_blk(fs->io, blk, 1, buf);
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68 | }
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69 |
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70 |
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