1/*-
2 * Copyright (c) 1991, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Kenneth Almquist.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#ifndef lint
34#if 0
35static char sccsid[] = "@(#)mystring.c	8.2 (Berkeley) 5/4/95";
36#endif
37#endif /* not lint */
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD$");
40
41/*
42 * String functions.
43 *
44 *	equal(s1, s2)		Return true if strings are equal.
45 *	number(s)		Convert a string of digits to an integer.
46 *	is_number(s)		Return true if s is a string of digits.
47 */
48
49#include <stdlib.h>
50#include "shell.h"
51#include "syntax.h"
52#include "error.h"
53#include "mystring.h"
54
55
56char nullstr[1];		/* zero length string */
57
58/*
59 * equal - #defined in mystring.h
60 */
61
62
63/*
64 * Convert a string of digits to an integer, printing an error message on
65 * failure.
66 */
67
68int
69number(const char *s)
70{
71	if (! is_number(s))
72		error("Illegal number: %s", s);
73	return atoi(s);
74}
75
76
77
78/*
79 * Check for a valid number.  This should be elsewhere.
80 */
81
82int
83is_number(const char *p)
84{
85	const char *q;
86
87	if (*p == '\0')
88		return 0;
89	while (*p == '0')
90		p++;
91	for (q = p; *q != '\0'; q++)
92		if (! is_digit(*q))
93			return 0;
94	if (q - p > 10 ||
95	    (q - p == 10 && memcmp(p, "2147483647", 10) > 0))
96		return 0;
97	return 1;
98}
99