Allow using a negative offset with callback buffers
[openal-soft.git] / utils / getopt.c
blobab1a246e30acc5b04078733e15fe9372579e8561
1 /* $NetBSD: getopt.c,v 1.26 2003/08/07 16:43:40 agc Exp $ */
3 /*
4 * Copyright (c) 1987, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 4. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
32 #if defined(LIBC_SCCS) && !defined(lint)
33 static char sccsid[] = "@(#)getopt.c 8.3 (Berkeley) 4/27/95";
34 #endif /* LIBC_SCCS and not lint */
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include "getopt.h"
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 */
46 #define BADCH (int)'?'
47 #define BADARG (int)':'
48 #define EMSG ""
51 * Get program name in Windows
53 const char * _getprogname(void);
56 * getopt --
57 * Parse argc/argv argument vector.
59 int
60 getopt(int nargc, char * const nargv[], const char *ostr)
62 static char *place = EMSG; /* option letter processing */
63 char *oli; /* option letter list index */
65 if (optreset || *place == 0) { /* update scanning pointer */
66 optreset = 0;
67 place = nargv[optind];
68 if (optind >= nargc || *place++ != '-') {
69 /* Argument is absent or is not an option */
70 place = EMSG;
71 return (-1);
73 optopt = *place++;
74 if (optopt == '-' && *place == 0) {
75 /* "--" => end of options */
76 ++optind;
77 place = EMSG;
78 return (-1);
80 if (optopt == 0) {
81 /* Solitary '-', treat as a '-' option
82 if the program (eg su) is looking for it. */
83 place = EMSG;
84 if (strchr(ostr, '-') == NULL)
85 return (-1);
86 optopt = '-';
88 } else
89 optopt = *place++;
91 /* See if option letter is one the caller wanted... */
92 if (optopt == ':' || (oli = strchr(ostr, optopt)) == NULL) {
93 if (*place == 0)
94 ++optind;
95 if (opterr && *ostr != ':')
96 (void)fprintf(stderr,
97 "%s: illegal option -- %c\n", _getprogname(),
98 optopt);
99 return (BADCH);
102 /* Does this option need an argument? */
103 if (oli[1] != ':') {
104 /* don't need argument */
105 optarg = NULL;
106 if (*place == 0)
107 ++optind;
108 } else {
109 /* Option-argument is either the rest of this argument or the
110 entire next argument. */
111 if (*place)
112 optarg = place;
113 else if (nargc > ++optind)
114 optarg = nargv[optind];
115 else {
116 /* option-argument absent */
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 _getprogname(), optopt);
124 return (BADCH);
126 place = EMSG;
127 ++optind;
129 return (optopt); /* return option letter */
132 const char * _getprogname() {
133 char *pgmptr = NULL;
134 _get_pgmptr(&pgmptr);
135 return strrchr(pgmptr,'\\')+1;