disk-utils/isosize.c

   1 /*
   2  * isosize.c - Andries Brouwer, 000608
   3  *
   4  * use header info to find size of iso9660 file system
   5  * output a number - useful in scripts
   6  *
   7  * Synopsis:
   8  *    isosize [-x] [-d <num>] <filename>
   9  *        where "-x" gives length in sectors and sector size while
  10  *              without this argument the size is given in bytes
  11  *        without "-x" gives length in bytes unless "-d <num>" is
  12  *              given. In the latter case the length in bytes divided
  13  *              by <num> is given
  14  *
  15  *  Version 2.03 2000/12/21
  16  *     - add "-d <num>" option and use long long to fix things > 2 GB
  17  *  Version 2.02 2000/10/11
  18  *     - error messages on IO failures [D. Gilbert]
  19  *
  20  */
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <getopt.h>
  24 #include <fcntl.h>
  25 #include <unistd.h>
  26 #include <errno.h>
  27
  28 #include "nls.h"
  29 #include "c.h"
  30 #include "strutils.h"
  31 #include "closestream.h"
  32 #include "iso9660.h"
  33
  34 #define ISOSIZE_EXIT_ALLFAILED  32
  35 #define ISOSIZE_EXIT_SOMEOK     64
  36
  37 static int is_iso(int fd)
  38 {
  39         char label[8];
  40
  41         if (pread(fd, &label, 8, 0x8000) == -1)
  42                 return 1;
  43         return memcmp(&label, &"\1CD001\1", 8);
  44 }
  45
  46 static int isosize(int argc, char *filenamep, int xflag, long divisor)
  47 {
  48         int fd, nsecs, ssize, rc = -1;
  49         unsigned char volume_space_size[8];
  50         unsigned char logical_block_size[4];
  51
  52         if ((fd = open(filenamep, O_RDONLY)) < 0) {
  53                 warn(_("cannot open %s"), filenamep);
  54                 goto done;
  55         }
  56         if (is_iso(fd))
  57                 warnx(_("%s: might not be an ISO filesystem"), filenamep);
  58
  59         if (pread(fd, volume_space_size, sizeof(volume_space_size), 0x8050) != sizeof(volume_space_size) ||
  60             pread(fd, logical_block_size, sizeof(logical_block_size), 0x8080) != sizeof(logical_block_size)) {
  61                 if (errno)
  62                         warn(_("read error on %s"), filenamep);
  63                 else
  64                         warnx(_("read error on %s"), filenamep);
  65                 goto done;
  66         }
  67
  68         nsecs = isonum_733(volume_space_size, xflag);
  69         /* isonum_723 returns nowadays always 2048 */
  70         ssize = isonum_723(logical_block_size, xflag);
  71
  72         if (1 < argc)
  73                 printf("%s: ", filenamep);
  74         if (xflag)
  75                 printf(_("sector count: %d, sector size: %d\n"), nsecs, ssize);
  76         else {
  77                 long long product = nsecs;
  78
  79                 if (divisor == 0)
  80                         printf("%lld\n", product * ssize);
  81                 else if (divisor == ssize)
  82                         printf("%d\n", nsecs);
  83                 else
  84                         printf("%lld\n", (product * ssize) / divisor);
  85         }
  86
  87         rc = 0;
  88 done:
  89         if (fd >= 0)
  90                 close(fd);
  91         return rc;
  92 }
  93
  94 static void __attribute__((__noreturn__)) usage(void)
  95 {
  96
  97         fputs(USAGE_HEADER, stdout);
  98         fprintf(stdout,
  99                 _(" %s [options] <iso9660_image_file> ...\n"),
 100                 program_invocation_short_name);
 101
 102         fputs(USAGE_SEPARATOR, stdout);
 103         fputs(_("Show the length of an ISO-9660 filesystem.\n"), stdout);
 104
 105         fputs(USAGE_OPTIONS, stdout);
 106         fputs(_(" -d, --divisor=<number>  divide the amount of bytes by <number>\n"), stdout);
 107         fputs(_(" -x, --sectors           show sector count and size\n"), stdout);
 108
 109         printf(USAGE_HELP_OPTIONS(25));
 110         printf(USAGE_MAN_TAIL("isosize(8)"));
 111
 112         exit(EXIT_SUCCESS);
 113 }
 114
 115 int main(int argc, char **argv)
 116 {
 117         int j, ct_err = 0, ct, opt, xflag = 0;
 118         long divisor = 0;
 119
 120         static const struct option longopts[] = {
 121                 {"divisor", required_argument, NULL, 'd'},
 122                 {"sectors", no_argument,       NULL, 'x'},
 123                 {"version", no_argument,       NULL, 'V'},
 124                 {"help",    no_argument,       NULL, 'h'},
 125                 {NULL, 0, NULL, 0}
 126         };
 127
 128         setlocale(LC_ALL, "");
 129         bindtextdomain(PACKAGE, LOCALEDIR);
 130         textdomain(PACKAGE);
 131         close_stdout_atexit();
 132
 133         while ((opt = getopt_long(argc, argv, "d:xVh", longopts, NULL)) != -1) {
 134                 switch (opt) {
 135                 case 'd':
 136                         divisor =
 137                             strtol_or_err(optarg,
 138                                           _("invalid divisor argument"));
 139                         break;
 140                 case 'x':
 141                         xflag = 1;
 142                         break;
 143                 case 'V':
 144                         print_version(EXIT_SUCCESS);
 145                 case 'h':
 146                         usage();
 147                 default:
 148                         errtryhelp(EXIT_FAILURE);
 149                 }
 150         }
 151
 152         ct = argc - optind;
 153
 154         if (ct <= 0) {
 155                 warnx(_("no device specified"));
 156                 errtryhelp(EXIT_FAILURE);
 157         }
 158
 159         for (j = optind; j < argc; j++) {
 160                 if (isosize(ct, argv[j], xflag, divisor) != 0)
 161                         ct_err++;
 162         }
 163
 164         return  ct == ct_err    ? ISOSIZE_EXIT_ALLFAILED :      /* all failed */
 165                 ct_err          ? ISOSIZE_EXIT_SOMEOK :         /* some ok */
 166                 EXIT_SUCCESS;                                   /* all success */
 167 }