xref: /freebsd-src/stand/libsa/getopt.c (revision 3e15b01d6914c927e37d1699645783acf286655c)
1*ca987d46SWarner Losh /*
2*ca987d46SWarner Losh  * Copyright (c) 1987, 1993, 1994
3*ca987d46SWarner Losh  *	The Regents of the University of California.  All rights reserved.
4*ca987d46SWarner Losh  *
5*ca987d46SWarner Losh  * Redistribution and use in source and binary forms, with or without
6*ca987d46SWarner Losh  * modification, are permitted provided that the following conditions
7*ca987d46SWarner Losh  * are met:
8*ca987d46SWarner Losh  * 1. Redistributions of source code must retain the above copyright
9*ca987d46SWarner Losh  *    notice, this list of conditions and the following disclaimer.
10*ca987d46SWarner Losh  * 2. Redistributions in binary form must reproduce the above copyright
11*ca987d46SWarner Losh  *    notice, this list of conditions and the following disclaimer in the
12*ca987d46SWarner Losh  *    documentation and/or other materials provided with the distribution.
13*ca987d46SWarner Losh  * 3. Neither the name of the University nor the names of its contributors
14*ca987d46SWarner Losh  *    may be used to endorse or promote products derived from this software
15*ca987d46SWarner Losh  *    without specific prior written permission.
16*ca987d46SWarner Losh  *
17*ca987d46SWarner Losh  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18*ca987d46SWarner Losh  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19*ca987d46SWarner Losh  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20*ca987d46SWarner Losh  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21*ca987d46SWarner Losh  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22*ca987d46SWarner Losh  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23*ca987d46SWarner Losh  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24*ca987d46SWarner Losh  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25*ca987d46SWarner Losh  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26*ca987d46SWarner Losh  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27*ca987d46SWarner Losh  * SUCH DAMAGE.
28*ca987d46SWarner Losh  */
29*ca987d46SWarner Losh 
30*ca987d46SWarner Losh #include "stand.h"
31*ca987d46SWarner Losh #include <string.h>
32*ca987d46SWarner Losh 
33*ca987d46SWarner Losh int	opterr = 1,		/* if error message should be printed */
34*ca987d46SWarner Losh 	optind = 1,		/* index into parent argv vector */
35*ca987d46SWarner Losh 	optopt,			/* character checked for validity */
36*ca987d46SWarner Losh 	optreset;		/* reset getopt */
37*ca987d46SWarner Losh char	*optarg;		/* argument associated with option */
38*ca987d46SWarner Losh 
39*ca987d46SWarner Losh #define	BADCH	(int)'?'
40*ca987d46SWarner Losh #define	BADARG	(int)':'
41*ca987d46SWarner Losh #define	EMSG	""
42*ca987d46SWarner Losh 
43*ca987d46SWarner Losh /*
44*ca987d46SWarner Losh  * getopt --
45*ca987d46SWarner Losh  *	Parse argc/argv argument vector.
46*ca987d46SWarner Losh  */
47*ca987d46SWarner Losh int
getopt(int nargc,char * const * nargv,const char * ostr)48*ca987d46SWarner Losh getopt(int nargc, char * const *nargv, const char *ostr)
49*ca987d46SWarner Losh {
50*ca987d46SWarner Losh 	static char *place = EMSG;		/* option letter processing */
51*ca987d46SWarner Losh 	char *oli;				/* option letter list index */
52*ca987d46SWarner Losh 
53*ca987d46SWarner Losh 	if (optreset || !*place) {		/* update scanning pointer */
54*ca987d46SWarner Losh 		optreset = 0;
55*ca987d46SWarner Losh 		if (optind >= nargc || *(place = nargv[optind]) != '-') {
56*ca987d46SWarner Losh 			place = EMSG;
57*ca987d46SWarner Losh 			return (-1);
58*ca987d46SWarner Losh 		}
59*ca987d46SWarner Losh 		if (place[1] && *++place == '-') {	/* found "--" */
60*ca987d46SWarner Losh 			++optind;
61*ca987d46SWarner Losh 			place = EMSG;
62*ca987d46SWarner Losh 			return (-1);
63*ca987d46SWarner Losh 		}
64*ca987d46SWarner Losh 	}					/* option letter okay? */
65*ca987d46SWarner Losh 	if ((optopt = (int)*place++) == (int)':' ||
66*ca987d46SWarner Losh 	    !(oli = strchr(ostr, optopt))) {
67*ca987d46SWarner Losh 		/*
68*ca987d46SWarner Losh 		 * if the user didn't specify '-' as an option,
69*ca987d46SWarner Losh 		 * assume it means -1.
70*ca987d46SWarner Losh 		 */
71*ca987d46SWarner Losh 		if (optopt == (int)'-')
72*ca987d46SWarner Losh 			return (-1);
73*ca987d46SWarner Losh 		if (!*place)
74*ca987d46SWarner Losh 			++optind;
75*ca987d46SWarner Losh 		if (opterr && *ostr != ':')
76*ca987d46SWarner Losh 			(void)printf("illegal option -- %c\n", optopt);
77*ca987d46SWarner Losh 		return (BADCH);
78*ca987d46SWarner Losh 	}
79*ca987d46SWarner Losh 	if (*++oli != ':') {			/* don't need argument */
80*ca987d46SWarner Losh 		optarg = NULL;
81*ca987d46SWarner Losh 		if (!*place)
82*ca987d46SWarner Losh 			++optind;
83*ca987d46SWarner Losh 	}
84*ca987d46SWarner Losh 	else {					/* need an argument */
85*ca987d46SWarner Losh 		if (*place)			/* no white space */
86*ca987d46SWarner Losh 			optarg = place;
87*ca987d46SWarner Losh 		else if (nargc <= ++optind) {	/* no arg */
88*ca987d46SWarner Losh 			place = EMSG;
89*ca987d46SWarner Losh 			if (*ostr == ':')
90*ca987d46SWarner Losh 				return (BADARG);
91*ca987d46SWarner Losh 			if (opterr)
92*ca987d46SWarner Losh 				(void)printf("option requires an argument -- %c\n", optopt);
93*ca987d46SWarner Losh 			return (BADCH);
94*ca987d46SWarner Losh 		}
95*ca987d46SWarner Losh 	 	else				/* white space */
96*ca987d46SWarner Losh 			optarg = nargv[optind];
97*ca987d46SWarner Losh 		place = EMSG;
98*ca987d46SWarner Losh 		++optind;
99*ca987d46SWarner Losh 	}
100*ca987d46SWarner Losh 	return (optopt);			/* dump back option letter */
101*ca987d46SWarner Losh }
102