The Tcpdump Group git mirrors - libpcap/blob - missing/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  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #if defined(LIBC_SCCS) && !defined(lint)
  35 static char sccsid[] = "@(#)getopt.c    8.3 (Berkeley) 4/27/95";
  36 #endif /* LIBC_SCCS and not lint */
  37
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41
  42 #include "getopt.h"
  43
  44 int     opterr = 1,             /* if error message should be printed */
  45         optind = 1,             /* index into parent argv vector */
  46         optopt,                 /* character checked for validity */
  47         optreset;               /* reset getopt */
  48 char    *optarg;                /* argument associated with option */
  49
  50 #define BADCH   (int)'?'
  51 #define BADARG  (int)':'
  52 #define EMSG    ""
  53
  54 /*
  55  * getopt --
  56  *      Parse argc/argv argument vector.
  57  */
  58 int
  59 getopt(int nargc, char * const *nargv, const char *ostr)
  60 {
  61         char *cp;
  62         static char *__progname;
  63         static char *place = EMSG;              /* option letter processing */
  64         char *oli;                              /* option letter list index */
  65
  66         if (__progname == NULL) {
  67                 if ((cp = strrchr(nargv[0], '/')) != NULL)
  68                         __progname = cp + 1;
  69                 else
  70                         __progname = nargv[0];
  71         }
  72         if (optreset || !*place) {              /* update scanning pointer */
  73                 optreset = 0;
  74                 if (optind >= nargc || *(place = nargv[optind]) != '-') {
  75                         place = EMSG;
  76                         return (-1);
  77                 }
  78                 if (place[1] && *++place == '-') {      /* found "--" */
  79                         ++optind;
  80                         place = EMSG;
  81                         return (-1);
  82                 }
  83         }
  84         optopt = (int)*place++;
  85         if (optopt == (int)':') {               /* option letter okay? */
  86                 if (!*place)
  87                         ++optind;
  88                 if (opterr && *ostr != ':')
  89                         (void)fprintf(stderr,
  90                             "%s: illegal option -- %c\n", __progname, optopt);
  91                 return (BADCH);
  92         }
  93         oli = strchr(ostr, optopt);
  94         if (!oli) {
  95                 /*
  96                  * if the user didn't specify '-' as an option,
  97                  * assume it means -1.
  98                  */
  99                 if (optopt == (int)'-')
 100                         return (-1);
 101                 if (!*place)
 102                         ++optind;
 103                 if (opterr && *ostr != ':')
 104                         (void)fprintf(stderr,
 105                             "%s: illegal option -- %c\n", __progname, optopt);
 106                 return (BADCH);
 107         }
 108         if (*++oli != ':') {                    /* don't need argument */
 109                 optarg = NULL;
 110                 if (!*place)
 111                         ++optind;
 112         }
 113         else {                                  /* need an argument */
 114                 if (*place)                     /* no white space */
 115                         optarg = place;
 116                 else if (nargc <= ++optind) {   /* no arg */
 117                         place = EMSG;
 118                         if (*ostr == ':')
 119                                 return (BADARG);
 120                         if (opterr)
 121                                 (void)fprintf(stderr,
 122                                     "%s: option requires an argument -- %c\n",
 123                                     __progname, optopt);
 124                         return (BADCH);
 125                 }
 126                 else                            /* white space */
 127                         optarg = nargv[optind];
 128                 place = EMSG;
 129                 ++optind;
 130         }
 131         return (optopt);                        /* dump back option letter */
 132 }