openblt

a hobby OS from the late 90s
git clone http://frotz.net/git/openblt.git
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getopt.c (4056B)


      1 /* $Id: //depot/blt/lib/libposix/getopt.c#1 $
      2 ** OpenBSD: getopt.c,v 1.2 1996/08/19 08:33:32 tholo Exp $
      3 **
      4 ** Copyright (c) 1987, 1993, 1994
      5 **     The Regents of the University of California.  All rights reserved.
      6 ** Copyright 1999 Sidney Cammeresi.
      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
     11 ** are met:
     12 **
     13 ** 1. Redistributions of source code must retain the above copyright
     14 **    notice, this list of conditions and the following disclaimer.
     15 ** 2. Redistributions in binary form must reproduce the above copyright
     16 **    notice, this list of conditions and the following disclaimer in the
     17 **    documentation and/or other materials provided with the distribution.
     18 ** 3. All advertising materials mentioning features or use of this software
     19 **    must display the following acknowledgement:
     20 **        This product includes software developed by the University of
     21 **        California, Berkeley and its contributors.
     22 ** 4. Neither the name of the University nor the names of its contributors
     23 **    may be used to endorse or promote products derived from this software
     24 **    without specific prior written permission.
     25 **
     26 ** THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     27 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     28 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     29 ** ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     30 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     31 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     32 ** OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     33 ** HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     34 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     35 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     36 ** SUCH DAMAGE.
     37 */
     38 
     39 #include <stdio.h>
     40 #include <stdlib.h>
     41 #include <string.h>
     42 #include <unistd.h>
     43 #include <blt/libsyms.h>
     44 
     45 weak_alias (_getopt, getopt)
     46 
     47 int	opterr = 1,   /* if error message should be printed */
     48     optind = 1,   /* index into parent argv vector */
     49     optopt,       /* character checked for validity */
     50     optreset;     /* reset getopt */
     51 char *optarg;    /* argument associated with option */
     52 
     53 extern char *__progname;
     54 
     55 #define	BADCH	(int)'?'
     56 #define	BADARG	(int)':'
     57 #define	EMSG	""
     58 
     59 #define fprintf(file, format, a...) _printf (format, ## a)
     60 
     61 /*
     62  * getopt --
     63  *	Parse argc/argv argument vector.
     64  */
     65 int _getopt (int nargc, char * const *nargv, const char *ostr)
     66 {
     67 	static char *place = EMSG;		/* option letter processing */
     68 	char *oli;				/* option letter list index */
     69 
     70 	if (optreset || !*place) {		/* update scanning pointer */
     71 		optreset = 0;
     72 		if (optind >= nargc || *(place = nargv[optind]) != '-') {
     73 			place = EMSG;
     74 			return (-1);
     75 		}
     76 		if (place[1] && *++place == '-') {	/* found "--" */
     77 			++optind;
     78 			place = EMSG;
     79 			return (-1);
     80 		}
     81 	}					/* option letter okay? */
     82 	if ((optopt = (int)*place++) == (int)':' ||
     83 	    !(oli = strchr(ostr, optopt))) {
     84 		/*
     85 		 * if the user didn't specify '-' as an option,
     86 		 * assume it means -1.
     87 		 */
     88 		if (optopt == (int)'-')
     89 			return (-1);
     90 		if (!*place)
     91 			++optind;
     92 		if (opterr && *ostr != ':')
     93 			(void)fprintf(stderr,
     94 			    "%s: illegal option -- %c\n", __progname, optopt);
     95 		return (BADCH);
     96 	}
     97 	if (*++oli != ':') {			/* don't need argument */
     98 		optarg = NULL;
     99 		if (!*place)
    100 			++optind;
    101 	}
    102 	else {					/* need an argument */
    103 		if (*place)			/* no white space */
    104 			optarg = place;
    105 		else if (nargc <= ++optind) {	/* no arg */
    106 			place = EMSG;
    107 			if (*ostr == ':')
    108 				return (BADARG);
    109 			if (opterr)
    110 				(void)fprintf(stderr,
    111 				    "%s: option requires an argument -- %c\n",
    112 				    __progname, optopt);
    113 			return (BADCH);
    114 		}
    115 	 	else				/* white space */
    116 			optarg = nargv[optind];
    117 		place = EMSG;
    118 		++optind;
    119 	}
    120 	return (optopt);			/* dump back option letter */
    121 }
    122