freebsd-skq/bin/sh/mystring.c
Peter Wemm aa9caaf657 Merge of 4.4-Lite2 sh source, plus some gcc -Wall cleaning. This is a
merge of parallel duplicate work by Steve Price and myself. :-]

There are some changes to the build that are my fault...  mkinit.c was
trying (poorly) to duplicate some of the work that make(1) is designed to
do.  The Makefile hackery is my fault too, the depend list was incomplete
because of some explicit OBJS+= entries, so mkdep wasn't picking up their
source file #includes.

This closes a pile of /bin/sh PR's, but not all of them..

Submitted by: Steve Price <steve@bonsai.hiwaay.net>, peter
1996-09-01 10:22:36 +00:00

140 lines
3.5 KiB
C

/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $Id: mystring.c,v 1.2 1994/09/24 02:57:59 davidg Exp $
*/
#ifndef lint
static char sccsid[] = "@(#)mystring.c 8.2 (Berkeley) 5/4/95";
#endif /* not lint */
/*
* String functions.
*
* equal(s1, s2) Return true if strings are equal.
* scopy(from, to) Copy a string.
* scopyn(from, to, n) Like scopy, but checks for overflow.
* number(s) Convert a string of digits to an integer.
* is_number(s) Return true if s is a string of digits.
*/
#include <stdlib.h>
#include "shell.h"
#include "syntax.h"
#include "error.h"
#include "mystring.h"
char nullstr[1]; /* zero length string */
/*
* equal - #defined in mystring.h
*/
/*
* scopy - #defined in mystring.h
*/
/*
* scopyn - copy a string from "from" to "to", truncating the string
* if necessary. "To" is always nul terminated, even if
* truncation is performed. "Size" is the size of "to".
*/
void
scopyn(from, to, size)
register char const *from;
register char *to;
register int size;
{
while (--size > 0) {
if ((*to++ = *from++) == '\0')
return;
}
*to = '\0';
}
/*
* prefix -- see if pfx is a prefix of string.
*/
int
prefix(pfx, string)
register char const *pfx;
register char const *string;
{
while (*pfx) {
if (*pfx++ != *string++)
return 0;
}
return 1;
}
/*
* Convert a string of digits to an integer, printing an error message on
* failure.
*/
int
number(s)
const char *s;
{
if (! is_number(s))
error2("Illegal number", (char *)s);
return atoi(s);
}
/*
* Check for a valid number. This should be elsewhere.
*/
int
is_number(p)
register const char *p;
{
do {
if (! is_digit(*p))
return 0;
} while (*++p != '\0');
return 1;
}