rosapps/applications/sysutils/mkdosfs/getopt.c

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   2  * This is an unpublished work copyright (c) 1998 HELIOS Software GmbH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