cksum.c

   1 /*
   2     Copyright © 2013 Alastair Stuart
   3
   4     This program is open source software: you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation, either version 3 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  12     GNU General Public License for more details.
  13 */
  14
  15 #include <stdbool.h>
  16 #include <stdio.h>
  17 #include <stdint.h>
  18 #include <string.h>
  19
  20 #define VERSION "0.01"
  21
  22 const uint32_t crc_table[256] = {
  23     0x00000000,
  24     0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535,
  25     0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b,
  26     0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148,
  27     0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856,
  28     0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63,
  29     0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1,
  30     0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6,
  31     0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac,
  32     0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599,
  33     0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87,
  34     0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106, 0x98d220bc,
  35     0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2,
  36     0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97,
  37     0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed,
  38     0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea,
  39     0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, 0x4db26158,
  40     0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d,
  41     0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73,
  42     0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010,
  43     0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, 0x5edef90e,
  44     0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b,
  45     0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739,
  46     0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e,
  47     0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344,
  48     0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671,
  49     0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f,
  50     0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4,
  51     0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda,
  52     0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef,
  53     0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795,
  54     0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92,
  55     0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0,
  56     0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785,
  57     0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b,
  58     0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8,
  59     0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, 0x88085ae6,
  60     0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3,
  61     0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661,
  62     0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66,
  63     0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, 0xbdbdf21c,
  64     0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729,
  65     0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37,
  66     0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
  67 };
  68
  69 size_t len = 0;
  70
  71 struct {
  72     bool zero;
  73 } flags;
  74
  75
  76 uint32_t crc32(FILE* input)
  77 {
  78     uint32_t c = 0xFFFFFFFF;
  79     int byte = fgetc(input);
  80     len++;
  81     while (byte != EOF)
  82     {
  83         c = crc_table[(c ^ byte) & 255] ^ (c >> 8);
  84         byte = fgetc(input);
  85         len++;
  86
  87     }
  88     return c ^ 0xFFFFFFFF;
  89 }
  90
  91 int main(int argc, char* argv[])
  92 {
  93     if (argc == 1) {
  94         fprintf(stderr, "%s: missing operand\n"
  95                         "Run '%s --help' for usage.\n",
  96                         argv[0], argv[0]);
  97         return 1;
  98     }
  99
 100     flags.zero = false;
 101
 102     // flag parsing
 103     int arg = 0;
 104     for (arg = 1; arg < argc; arg++)
 105     {
 106         if (strcmp("--zero", argv[arg]) == 0 || strcmp("-z", argv[arg]) == 0) {
 107             flags.zero = true;
 108         } else if (strcmp("--help", argv[arg]) == 0 || strcmp("-h", argv[arg]) == 0) {
 109             printf("Usage: %s [file ...]\n", argv[0]);
 110             printf("Print CRC checksum and byte counts of each [file].\n"
 111                    "\n"
 112                    "    -z, --zero          Zero pad checksums.\n"
 113                    "\n"
 114                    "    --help              Print this message.\n"
 115                    "    --version           Show version info.\n");
 116             return 0;
 117         } else if (strcmp("--version", argv[arg]) == 0 || strcmp("-v", argv[arg]) == 0) {
 118             printf("cksum (mutos) v"VERSION"\n");
 119             return 0;
 120         } else {
 121             break;
 122         }
 123     }
 124
 125     for ( ; arg < argc; arg++)
 126     {
 127         FILE* file = fopen(argv[arg], "r");
 128         printf(flags.zero ? "%010u %zd %s\n" : "%u %zd %s\n" , crc32(file), len, argv[arg]);
 129         fclose(file);
 130         len = 0;
 131     }
 132     return 0;
 133 }