libc/unistd/getopt-susv3.c

   1 /*  Copyright (C) 2003     Manuel Novoa III
   2  *
   3  * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
   4  */
   5
   6 /*  ATTENTION!   ATTENTION!   ATTENTION!   ATTENTION!   ATTENTION!
   7  *
   8  *  Besides uClibc, I'm using this code in my libc for elks, which is
   9  *  a 16-bit environment with a fairly limited compiler.  It would make
  10  *  things much easier for me if this file isn't modified unnecessarily.
  11  *  In particular, please put any new or replacement functions somewhere
  12  *  else, and modify the makefile to use your version instead.
  13  *  Thanks.  Manuel
  14  *
  15  *  ATTENTION!   ATTENTION!   ATTENTION!   ATTENTION!   ATTENTION! */
  16
  17 /* Sep 7, 2003
  18  *   Initial version of a SUSv3 compliant getopt().
  19  */
  20
  21 #include <unistd.h>
  22 #include <string.h>
  23 #include <stdio.h>
  24 #include <getopt.h>
  25
  26 #ifdef __BCC__
  27 static const char missing[] = "option requires an argument";
  28 static const char illegal[] = "illegal option";
  29 #else
  30 static const char missing[] = "%s: option requires an argument -- %c\n";
  31 static const char illegal[] = "%s: illegal option -- %c\n";
  32 #endif
  33
  34 int opterr = 1;
  35 int optind = 1;
  36 int optopt = 0;
  37 char *optarg = NULL;
  38
  39 int getopt(int argc, char * const argv[], const char *optstring)
  40 {
  41         static const char *o;           /* multi opt position */
  42         register const char *p;
  43         register const char *s;
  44         int retval = -1;
  45
  46         optopt = 0;
  47         optarg = NULL;
  48
  49         if (!o) {                               /* Not in a multi-option arg. */
  50                 if ((optind >= argc)    /* No more args? */
  51                         || ((p = argv[optind]) == NULL) /* Missing? */
  52                         || (*p != '-')          /* Not an option? */
  53                         || (!*++p)                      /* "-" case? */
  54                         ) {
  55                         goto DONE;
  56                 }
  57                 if ((*p == '-') && (p[1] == 0)) { /* "--" case. */
  58 /*                      ++optind; */
  59 /*                      goto DONE; */
  60                         goto NEXTOPT;           /* Less code generated... */
  61                 }
  62                 o = p;
  63         }
  64
  65 #ifdef __BCC__
  66         p = o;                                          /* Sigh... Help out bcc. */
  67 #define o p
  68 #endif
  69         retval = (unsigned char) *o; /* Avoid problems for char val of -1. */
  70
  71         if ((*o == ':') || !(s = strchr(optstring, *o))) { /* Illegal option? */
  72                 s = illegal;
  73                 retval = '?';
  74                 goto BAD;
  75         }
  76
  77         if (s[1] == ':') {                      /* Option takes an arg? */
  78                 if (o[1]) {                                     /* No space between option and arg? */
  79                         optarg = (char *)(o + 1);
  80                         goto NEXTOPT;
  81                 }
  82
  83                 if (optind + 1 < argc) {        /* Space between option and arg? */
  84                         optarg = argv[++optind];
  85                 } else {                                /* Out of args! */
  86                         s = missing;
  87                         retval = ':';
  88                 BAD:
  89                         optopt = *o;
  90                         if (*optstring != ':') {
  91                                 retval = '?';
  92                                 if (opterr) {
  93 #ifdef __BCC__
  94                                         fprintf(stderr, "%s: %s -- %c\n", argv[0], s, *o);
  95 #else
  96                                         fprintf(stderr, _(s), argv[0], *o);
  97 #endif
  98                                 }
  99                         }
 100                 }
 101         }
 102
 103 #ifdef __BCC__
 104 #undef o
 105 #endif
 106
 107         if (!*++o) {
 108         NEXTOPT:
 109                 o = NULL;
 110                 ++optind;
 111         }
 112  DONE:
 113         return retval;
 114 }
 115 libc_hidden_def(getopt)