workbench/libs/lcms2/utils/common/xgetopt.c

   1 /*
   2     getopt.c
   3
   4 */
   5
   6 #include <errno.h>
   7 #include <string.h>
   8 #include <stdio.h>
   9
  10 int     xoptind = 1;    /* index of which argument is next  */
  11 char   *xoptarg;        /* pointer to argument of current option */
  12 int     xopterr = 0;    /* allow error message  */
  13
  14 static  char   *letP = NULL;    /* remember next option char's location */
  15 char    SW = '-';                               /* DOS switch character, either '-' or '/' */
  16
  17 /*
  18   Parse the command line options, System V style.
  19
  20   Standard option syntax is:
  21
  22     option ::= SW [optLetter]* [argLetter space* argument]
  23
  24 */
  25
  26 int xgetopt(int argc, char *argv[], char *optionS)
  27 {
  28     unsigned char ch;
  29     char *optP;
  30
  31     if (SW == 0) {
  32         SW = '/';
  33     }
  34
  35     if (argc > xoptind) {
  36         if (letP == NULL) {
  37             if ((letP = argv[xoptind]) == NULL ||
  38                 *(letP++) != SW)  goto gopEOF;
  39             if (*letP == SW) {
  40                 xoptind++;  goto gopEOF;
  41             }
  42         }
  43         if (0 == (ch = *(letP++))) {
  44             xoptind++;  goto gopEOF;
  45         }
  46         if (':' == ch  ||  (optP = strchr(optionS, ch)) == NULL)
  47             goto gopError;
  48         if (':' == *(++optP)) {
  49             xoptind++;
  50             if (0 == *letP) {
  51                 if (argc <= xoptind)  goto  gopError;
  52                 letP = argv[xoptind++];
  53             }
  54             xoptarg = letP;
  55             letP = NULL;
  56         } else {
  57             if (0 == *letP) {
  58                 xoptind++;
  59                 letP = NULL;
  60             }
  61             xoptarg = NULL;
  62         }
  63         return ch;
  64     }
  65 gopEOF:
  66     xoptarg = letP = NULL;
  67     return EOF;
  68
  69 gopError:
  70     xoptarg = NULL;
  71     errno  = EINVAL;
  72     if (xopterr)
  73         perror ("get command line option");
  74     return ('?');
  75 }