rosapps/applications/sysutils/mkdosfs/getopt.c

   1 /*
   2  * $Id$
   3  * This is an unpublished work copyright (c) 1998 HELIOS Software GmbH
   4  * 30827 Garbsen, Germany
   5  */
   6
   7
   8 #include <stdio.h>
   9 #include <string.h>
  10 #ifdef HAS_UNISTD
  11 # include <unistd.h>
  12 #endif
  13
  14 char *optarg;
  15 int optind = 1;
  16 int opterr = 1;
  17 int optopt;
  18 static int subopt;
  19 static int suboptind = 1;
  20
  21 int getopt(int argc, char *const argv[], const char * optstring)
  22 {
  23         char *curopt;
  24         char *p;
  25         int cursubopt;
  26
  27         if (suboptind == optind-1 && argv[suboptind][subopt] != '\0') {
  28                 curopt = (char *)argv[suboptind];
  29         } else {
  30                 curopt = (char *)argv[optind];
  31                 if (curopt == NULL || curopt[0] != '-' || strcmp(curopt, "-") == 0)
  32                         return -1;
  33                 suboptind = optind;
  34                 subopt = 1;
  35                 optind++;
  36                 if (strcmp(curopt, "--") == 0)
  37                         return -1;
  38         }
  39         cursubopt = subopt++;
  40         if ((p = strchr(optstring, curopt[cursubopt])) == NULL) {
  41                 optopt = curopt[cursubopt];
  42                 if (opterr)
  43                         fprintf(stderr, "%s: illegal option -- %c\n", argv[0], optopt);
  44                 return '?';
  45         }
  46         if (p[1] == ':') {
  47                 if (curopt[cursubopt+1] != '\0') {
  48                         optarg = curopt+cursubopt+1;
  49                         suboptind++;
  50                         return p[0];
  51                 }
  52                 if (argv[optind] == NULL) {
  53                         optopt = p[0];
  54                         if (opterr)
  55                                 fprintf(stderr, "%s: option requires an argument -- %c\n", argv[0], optopt);
  56                         if (*optstring == ':')
  57                                 return ':';
  58                         return '?';
  59                 }
  60                 optarg = argv[optind++];
  61         }
  62         return p[0];
  63 }