minix/commands/cawf/getopt.c

   1 #ifndef __minix
   2 /*
   3 Newsgroups: mod.std.unix
   4 Subject: public domain AT&T getopt source
   5 Date: 3 Nov 85 19:34:15 GMT
   6
   7 Here's something you've all been waiting for:  the AT&T public domain
   8 source for getopt(3).  It is the code which was given out at the 1985
   9 UNIFORUM conference in Dallas.  I obtained it by electronic mail
  10 directly from AT&T.  The people there assure me that it is indeed
  11 in the public domain.
  12 */
  13
  14
  15 /*LINTLIBRARY*/
  16 #define NULL    0
  17 #define EOF     (-1)
  18 #define ERR(s, c)       if(opterr){\
  19         extern int strlen(), write();\
  20         char errbuf[2];\
  21         errbuf[0] = c; errbuf[1] = '\n';\
  22         (void) write(2, argv[0], (unsigned)strlen(argv[0]));\
  23         (void) write(2, s, (unsigned)strlen(s));\
  24         (void) write(2, errbuf, 2);}
  25
  26 extern int strcmp();
  27 extern char *strchr();
  28
  29 int     opterr = 1;
  30 int     optind = 1;
  31 int     optopt;
  32 char    *optarg;
  33
  34 int getopt(int argc, char **argv, char **opts) {
  35         static int sp = 1;
  36         register int c;
  37         register char *cp;
  38
  39         if(sp == 1)
  40                 if(optind >= argc ||
  41                    argv[optind][0] != '-' || argv[optind][1] == '\0')
  42                         return(EOF);
  43                 else if(strcmp(argv[optind], "--") == NULL) {
  44                         optind++;
  45                         return(EOF);
  46                 }
  47         optopt = c = argv[optind][sp];
  48         if(c == ':' || (cp=strchr(opts, c)) == NULL) {
  49                 ERR(": illegal option -- ", c);
  50                 if(argv[optind][++sp] == '\0') {
  51                         optind++;
  52                         sp = 1;
  53                 }
  54                 return('?');
  55         }
  56         if(*++cp == ':') {
  57                 if(argv[optind][sp+1] != '\0')
  58                         optarg = &argv[optind++][sp+1];
  59                 else if(++optind >= argc) {
  60                         ERR(": option requires an argument -- ", c);
  61                         sp = 1;
  62                         return('?');
  63                 } else
  64                         optarg = argv[optind++];
  65                 sp = 1;
  66         } else {
  67                 if(argv[optind][++sp] == '\0') {
  68                         sp = 1;
  69                         optind++;
  70                 }
  71                 optarg = NULL;
  72         }
  73         return(c);
  74 }
  75 #endif /* !__minix */