1 /*
2  * getopt.c --
3  *
4  *      Standard UNIX getopt function.  Code is from BSD.
5  *
6  * Copyright (c) 1987-2002 The Regents of the University of California.
7  * 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 are met:
11  *
12  * A. Redistributions of source code must retain the above copyright notice,
13  *    this list of conditions and the following disclaimer.
14  * B. Redistributions in binary form must reproduce the above copyright notice,
15  *    this list of conditions and the following disclaimer in the documentation
16  *    and/or other materials provided with the distribution.
17  * C. Neither the names of the copyright holders nor the names of its
18  *    contributors may be used to endorse or promote products derived from this
19  *    software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS
22  * IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
23  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE
25  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /* #if !defined(lint)
35  * static char sccsid[] = "@(#)getopt.c 8.2 (Berkeley) 4/2/94";
36  * #endif
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
getopt(int nargc,char * const * nargv,const char * ostr)59 getopt(int nargc, char *const *nargv, const char *ostr) {
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 (EOF);
68 	}
69 	if (place[1] && *++place == '-') { /* found "--" */
70 	    ++optind;
71 	    place = EMSG;
72 	    return (EOF);
73 	}
74     } /* option letter okay? */
75     if ((optopt = (int)*place++) == (int)':' || !(oli = (char *)strchr(ostr, optopt))) {
76 	/*
77 	 * if the user didn't specify '-' as an option,
78 	 * assume it means EOF.
79 	 */
80 	if (optopt == (int)'-')
81 	    return (EOF);
82 	if (!*place)
83 	    ++optind;
84 	if (opterr && *ostr != ':')
85 	    (void)fprintf(stderr, "illegal option -- %c\n", optopt);
86 	return (BADCH);
87     }
88     if (*++oli != ':') { /* don't need argument */
89 	optarg = NULL;
90 	if (!*place)
91 	    ++optind;
92     }
93     else {          /* need an argument */
94 	if (*place) /* no white space */
95 	    optarg = place;
96 	else if (nargc <= ++optind) { /* no arg */
97 	    place = EMSG;
98 	    if (*ostr == ':')
99 		return (BADARG);
100 	    if (opterr)
101 		(void)fprintf(stderr, "option requires an argument -- %c\n", optopt);
102 	    return (BADCH);
103 	}
104 	else /* white space */
105 	    optarg = nargv[optind];
106 	place = EMSG;
107 	++optind;
108     }
109     return (optopt); /* dump back option letter */
110 }
111