Contents of /trunk/mkinitrd-magellan/busybox/coreutils/cksum.c
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Revision 984 -
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Sun May 30 11:32:42 2010 UTC (14 years, 4 months ago) by niro
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File size: 1658 byte(s)
Sun May 30 11:32:42 2010 UTC (14 years, 4 months ago) by niro
File MIME type: text/plain
File size: 1658 byte(s)
-updated to busybox-1.16.1 and enabled blkid/uuid support in default config
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * cksum - calculate the CRC32 checksum of a file |
4 | * |
5 | * Copyright (C) 2006 by Rob Sullivan, with ideas from code by Walter Harms |
6 | * |
7 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
8 | */ |
9 | #include "libbb.h" |
10 | |
11 | int cksum_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
12 | int cksum_main(int argc UNUSED_PARAM, char **argv) |
13 | { |
14 | uint32_t *crc32_table = crc32_filltable(NULL, 1); |
15 | uint32_t crc; |
16 | off_t length, filesize; |
17 | int bytes_read; |
18 | int exit_code = EXIT_SUCCESS; |
19 | uint8_t *cp; |
20 | |
21 | #if ENABLE_DESKTOP |
22 | getopt32(argv, ""); /* coreutils 6.9 compat */ |
23 | argv += optind; |
24 | #else |
25 | argv++; |
26 | #endif |
27 | |
28 | do { |
29 | int fd = open_or_warn_stdin(*argv ? *argv : bb_msg_standard_input); |
30 | |
31 | if (fd < 0) { |
32 | exit_code = EXIT_FAILURE; |
33 | continue; |
34 | } |
35 | crc = 0; |
36 | length = 0; |
37 | |
38 | #define read_buf bb_common_bufsiz1 |
39 | while ((bytes_read = safe_read(fd, read_buf, sizeof(read_buf))) > 0) { |
40 | cp = (uint8_t *) read_buf; |
41 | length += bytes_read; |
42 | do { |
43 | crc = (crc << 8) ^ crc32_table[(crc >> 24) ^ *cp++]; |
44 | } while (--bytes_read); |
45 | } |
46 | close(fd); |
47 | |
48 | filesize = length; |
49 | |
50 | while (length) { |
51 | crc = (crc << 8) ^ crc32_table[(uint8_t)(crc >> 24) ^ (uint8_t)length]; |
52 | /* must ensure that shift is unsigned! */ |
53 | if (sizeof(length) <= sizeof(unsigned)) |
54 | length = (unsigned)length >> 8; |
55 | else if (sizeof(length) <= sizeof(unsigned long)) |
56 | length = (unsigned long)length >> 8; |
57 | else |
58 | length = (unsigned long long)length >> 8; |
59 | } |
60 | crc = ~crc; |
61 | |
62 | printf((*argv ? "%"PRIu32" %"OFF_FMT"i %s\n" : "%"PRIu32" %"OFF_FMT"i\n"), |
63 | crc, filesize, *argv); |
64 | } while (*argv && *++argv); |
65 | |
66 | fflush_stdout_and_exit(exit_code); |
67 | } |