xref: /freebsd/bin/sh/mystring.c (revision aa9caaf65748ace0f3cd08c2deaf3ef3048d6e4d)
14b88c807SRodney W. Grimes /*-
24b88c807SRodney W. Grimes  * Copyright (c) 1991, 1993
34b88c807SRodney W. Grimes  *	The Regents of the University of California.  All rights reserved.
44b88c807SRodney W. Grimes  *
54b88c807SRodney W. Grimes  * This code is derived from software contributed to Berkeley by
64b88c807SRodney W. Grimes  * Kenneth Almquist.
74b88c807SRodney W. Grimes  *
84b88c807SRodney W. Grimes  * Redistribution and use in source and binary forms, with or without
94b88c807SRodney W. Grimes  * modification, are permitted provided that the following conditions
104b88c807SRodney W. Grimes  * are met:
114b88c807SRodney W. Grimes  * 1. Redistributions of source code must retain the above copyright
124b88c807SRodney W. Grimes  *    notice, this list of conditions and the following disclaimer.
134b88c807SRodney W. Grimes  * 2. Redistributions in binary form must reproduce the above copyright
144b88c807SRodney W. Grimes  *    notice, this list of conditions and the following disclaimer in the
154b88c807SRodney W. Grimes  *    documentation and/or other materials provided with the distribution.
164b88c807SRodney W. Grimes  * 3. All advertising materials mentioning features or use of this software
174b88c807SRodney W. Grimes  *    must display the following acknowledgement:
184b88c807SRodney W. Grimes  *	This product includes software developed by the University of
194b88c807SRodney W. Grimes  *	California, Berkeley and its contributors.
204b88c807SRodney W. Grimes  * 4. Neither the name of the University nor the names of its contributors
214b88c807SRodney W. Grimes  *    may be used to endorse or promote products derived from this software
224b88c807SRodney W. Grimes  *    without specific prior written permission.
234b88c807SRodney W. Grimes  *
244b88c807SRodney W. Grimes  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
254b88c807SRodney W. Grimes  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
264b88c807SRodney W. Grimes  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
274b88c807SRodney W. Grimes  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
284b88c807SRodney W. Grimes  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
294b88c807SRodney W. Grimes  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
304b88c807SRodney W. Grimes  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
314b88c807SRodney W. Grimes  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
324b88c807SRodney W. Grimes  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
334b88c807SRodney W. Grimes  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
344b88c807SRodney W. Grimes  * SUCH DAMAGE.
3589730b29SDavid Greenman  *
36aa9caaf6SPeter Wemm  *	$Id: mystring.c,v 1.2 1994/09/24 02:57:59 davidg Exp $
374b88c807SRodney W. Grimes  */
384b88c807SRodney W. Grimes 
394b88c807SRodney W. Grimes #ifndef lint
40aa9caaf6SPeter Wemm static char sccsid[] = "@(#)mystring.c	8.2 (Berkeley) 5/4/95";
414b88c807SRodney W. Grimes #endif /* not lint */
424b88c807SRodney W. Grimes 
434b88c807SRodney W. Grimes /*
444b88c807SRodney W. Grimes  * String functions.
454b88c807SRodney W. Grimes  *
464b88c807SRodney W. Grimes  *	equal(s1, s2)		Return true if strings are equal.
474b88c807SRodney W. Grimes  *	scopy(from, to)		Copy a string.
484b88c807SRodney W. Grimes  *	scopyn(from, to, n)	Like scopy, but checks for overflow.
494b88c807SRodney W. Grimes  *	number(s)		Convert a string of digits to an integer.
504b88c807SRodney W. Grimes  *	is_number(s)		Return true if s is a string of digits.
514b88c807SRodney W. Grimes  */
524b88c807SRodney W. Grimes 
53aa9caaf6SPeter Wemm #include <stdlib.h>
544b88c807SRodney W. Grimes #include "shell.h"
554b88c807SRodney W. Grimes #include "syntax.h"
564b88c807SRodney W. Grimes #include "error.h"
574b88c807SRodney W. Grimes #include "mystring.h"
584b88c807SRodney W. Grimes 
594b88c807SRodney W. Grimes 
604b88c807SRodney W. Grimes char nullstr[1];		/* zero length string */
614b88c807SRodney W. Grimes 
624b88c807SRodney W. Grimes /*
634b88c807SRodney W. Grimes  * equal - #defined in mystring.h
644b88c807SRodney W. Grimes  */
654b88c807SRodney W. Grimes 
664b88c807SRodney W. Grimes /*
674b88c807SRodney W. Grimes  * scopy - #defined in mystring.h
684b88c807SRodney W. Grimes  */
694b88c807SRodney W. Grimes 
704b88c807SRodney W. Grimes 
714b88c807SRodney W. Grimes /*
724b88c807SRodney W. Grimes  * scopyn - copy a string from "from" to "to", truncating the string
734b88c807SRodney W. Grimes  *		if necessary.  "To" is always nul terminated, even if
744b88c807SRodney W. Grimes  *		truncation is performed.  "Size" is the size of "to".
754b88c807SRodney W. Grimes  */
764b88c807SRodney W. Grimes 
774b88c807SRodney W. Grimes void
784b88c807SRodney W. Grimes scopyn(from, to, size)
794b88c807SRodney W. Grimes 	register char const *from;
804b88c807SRodney W. Grimes 	register char *to;
814b88c807SRodney W. Grimes 	register int size;
824b88c807SRodney W. Grimes 	{
834b88c807SRodney W. Grimes 
844b88c807SRodney W. Grimes 	while (--size > 0) {
854b88c807SRodney W. Grimes 		if ((*to++ = *from++) == '\0')
864b88c807SRodney W. Grimes 			return;
874b88c807SRodney W. Grimes 	}
884b88c807SRodney W. Grimes 	*to = '\0';
894b88c807SRodney W. Grimes }
904b88c807SRodney W. Grimes 
914b88c807SRodney W. Grimes 
924b88c807SRodney W. Grimes /*
934b88c807SRodney W. Grimes  * prefix -- see if pfx is a prefix of string.
944b88c807SRodney W. Grimes  */
954b88c807SRodney W. Grimes 
964b88c807SRodney W. Grimes int
974b88c807SRodney W. Grimes prefix(pfx, string)
984b88c807SRodney W. Grimes 	register char const *pfx;
994b88c807SRodney W. Grimes 	register char const *string;
1004b88c807SRodney W. Grimes 	{
1014b88c807SRodney W. Grimes 	while (*pfx) {
1024b88c807SRodney W. Grimes 		if (*pfx++ != *string++)
1034b88c807SRodney W. Grimes 			return 0;
1044b88c807SRodney W. Grimes 	}
1054b88c807SRodney W. Grimes 	return 1;
1064b88c807SRodney W. Grimes }
1074b88c807SRodney W. Grimes 
1084b88c807SRodney W. Grimes 
1094b88c807SRodney W. Grimes /*
1104b88c807SRodney W. Grimes  * Convert a string of digits to an integer, printing an error message on
1114b88c807SRodney W. Grimes  * failure.
1124b88c807SRodney W. Grimes  */
1134b88c807SRodney W. Grimes 
1144b88c807SRodney W. Grimes int
1154b88c807SRodney W. Grimes number(s)
1164b88c807SRodney W. Grimes 	const char *s;
1174b88c807SRodney W. Grimes 	{
1184b88c807SRodney W. Grimes 
1194b88c807SRodney W. Grimes 	if (! is_number(s))
1204b88c807SRodney W. Grimes 		error2("Illegal number", (char *)s);
1214b88c807SRodney W. Grimes 	return atoi(s);
1224b88c807SRodney W. Grimes }
1234b88c807SRodney W. Grimes 
1244b88c807SRodney W. Grimes 
1254b88c807SRodney W. Grimes 
1264b88c807SRodney W. Grimes /*
1274b88c807SRodney W. Grimes  * Check for a valid number.  This should be elsewhere.
1284b88c807SRodney W. Grimes  */
1294b88c807SRodney W. Grimes 
1304b88c807SRodney W. Grimes int
1314b88c807SRodney W. Grimes is_number(p)
1324b88c807SRodney W. Grimes 	register const char *p;
1334b88c807SRodney W. Grimes 	{
1344b88c807SRodney W. Grimes 	do {
1354b88c807SRodney W. Grimes 		if (! is_digit(*p))
1364b88c807SRodney W. Grimes 			return 0;
1374b88c807SRodney W. Grimes 	} while (*++p != '\0');
1384b88c807SRodney W. Grimes 	return 1;
1394b88c807SRodney W. Grimes }
140