lib/libstand/getopt.c

   1 /*
   2  * Copyright (c) 1987, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #include <sys/cdefs.h>
  31 __FBSDID("$FreeBSD$");
  32
  33 #if defined(LIBC_SCCS) && !defined(lint)
  34 static char sccsid[] = "@(#)getopt.c    8.3 (Berkeley) 4/27/95";
  35 #endif /* LIBC_SCCS and not lint */
  36
  37 #include "stand.h"
  38 #include <string.h>
  39
  40 int     opterr = 1,             /* if error message should be printed */
  41         optind = 1,             /* index into parent argv vector */
  42         optopt,                 /* character checked for validity */
  43         optreset;               /* reset getopt */
  44 char    *optarg;                /* argument associated with option */
  45
  46 #define BADCH   (int)'?'
  47 #define BADARG  (int)':'
  48 #define EMSG    ""
  49
  50 /*
  51  * getopt --
  52  *      Parse argc/argv argument vector.
  53  */
  54 int
  55 getopt(nargc, nargv, ostr)
  56         int nargc;
  57         char * const *nargv;
  58         const char *ostr;
  59 {
  60         static char *place = EMSG;              /* option letter processing */
  61         char *oli;                              /* option letter list index */
  62
  63         if (optreset || !*place) {              /* update scanning pointer */
  64                 optreset = 0;
  65                 if (optind >= nargc || *(place = nargv[optind]) != '-') {
  66                         place = EMSG;
  67                         return (-1);
  68                 }
  69                 if (place[1] && *++place == '-') {      /* found "--" */
  70                         ++optind;
  71                         place = EMSG;
  72                         return (-1);
  73                 }
  74         }                                       /* option letter okay? */
  75         if ((optopt = (int)*place++) == (int)':' ||
  76             !(oli = strchr(ostr, optopt))) {
  77                 /*
  78                  * if the user didn't specify '-' as an option,
  79                  * assume it means -1.
  80                  */
  81                 if (optopt == (int)'-')
  82                         return (-1);
  83                 if (!*place)
  84                         ++optind;
  85                 if (opterr && *ostr != ':')
  86                         (void)printf("illegal option -- %c\n", optopt);
  87                 return (BADCH);
  88         }
  89         if (*++oli != ':') {                    /* don't need argument */
  90                 optarg = NULL;
  91                 if (!*place)
  92                         ++optind;
  93         }
  94         else {                                  /* need an argument */
  95                 if (*place)                     /* no white space */
  96                         optarg = place;
  97                 else if (nargc <= ++optind) {   /* no arg */
  98                         place = EMSG;
  99                         if (*ostr == ':')
 100                                 return (BADARG);
 101                         if (opterr)
 102                                 (void)printf("option requires an argument -- %c\n", optopt);
 103                         return (BADCH);
 104                 }
 105                 else                            /* white space */
 106                         optarg = nargv[optind];
 107                 place = EMSG;
 108                 ++optind;
 109         }
 110         return (optopt);                        /* dump back option letter */
 111 }