1 /* $NetBSD: getopt.c,v 1.29 2014/06/05 22:00:22 christos Exp $ */
2
3 /*-
4 * SPDX-License-Identifier: BSD-3-Clause
5 *
6 * Copyright (c) 1987, 1993, 1994
7 * The Regents of the University of California. All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. 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 #include "namespace.h"
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <unistd.h>
42 #include "un-namespace.h"
43
44 #include "libc_private.h"
45
46 int opterr = 1, /* if error message should be printed */
47 optind = 1, /* index into parent argv vector */
48 optopt, /* character checked for validity */
49 optreset; /* reset getopt */
50 char *optarg; /* argument associated with option */
51
52 #define BADCH (int)'?'
53 #define BADARG (int)':'
54 static char EMSG[] = "";
55 /*
56 * getopt --
57 * Parse argc/argv argument vector.
58 */
59 int
getopt(int nargc,char * const nargv[],const char * ostr)60 getopt(int nargc, char * const nargv[], const char *ostr)
61 {
62 static char *place = EMSG; /* option letter processing */
63 char *oli; /* option letter list index */
64
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);
72 }
73 optopt = *place++;
74 if (optopt == '-' && *place == 0) {
75 /* "--" => end of options */
76 ++optind;
77 place = EMSG;
78 return (-1);
79 }
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 = '-';
87 }
88 } else
89 optopt = *place++;
90
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);
100 }
101
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 (oli[2] == ':')
114 /*
115 * GNU Extension, for optional arguments if the rest of
116 * the argument is empty, we return NULL
117 */
118 optarg = NULL;
119 else if (nargc > ++optind)
120 optarg = nargv[optind];
121 else {
122 /* option-argument absent */
123 place = EMSG;
124 if (*ostr == ':')
125 return (BADARG);
126 if (opterr)
127 (void)fprintf(stderr,
128 "%s: option requires an argument -- %c\n",
129 _getprogname(), optopt);
130 return (BADCH);
131 }
132 place = EMSG;
133 ++optind;
134 }
135 return (optopt); /* return option letter */
136 }
137