[821] | 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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