1 /* $NetBSD: mystring.c,v 1.21 2024/07/13 13:43:58 kre Exp $ */
2
3 /*-
4 * Copyright (c) 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Kenneth Almquist.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
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. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <sys/cdefs.h>
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)mystring.c 8.2 (Berkeley) 5/4/95";
39 #else
40 __RCSID("$NetBSD: mystring.c,v 1.21 2024/07/13 13:43:58 kre Exp $");
41 #endif
42 #endif /* not lint */
43
44 /*
45 * String functions.
46 *
47 * equal(s1, s2) Return true if strings are equal.
48 * scopy(from, to) Copy a string.
49 * scopyn(from, to, n) Like scopy, but checks for overflow.
50 * number(s) Convert a string of digits to an integer.
51 * is_number(s) Return true if s is a string of digits.
52 */
53
54 #include <inttypes.h>
55 #include <limits.h>
56 #include <stdlib.h>
57 #include <strings.h>
58
59 #include "shell.h"
60 #include "syntax.h"
61 #include "error.h"
62 #include "mystring.h"
63
64
65 const char nullstr[1]; /* zero length string */
66
67 /*
68 * equal - #defined in mystring.h
69 */
70
71 /*
72 * scopy - #defined in mystring.h
73 */
74
75
76 /*
77 * scopyn - copy a string from "from" to "to", truncating the string
78 * if necessary. "To" is always nul terminated, even if
79 * truncation is performed. "Size" is the size of "to".
80 */
81
82 void
scopyn(const char * from,char * to,int size)83 scopyn(const char *from, char *to, int size)
84 {
85
86 while (--size > 0) {
87 if ((*to++ = *from++) == '\0')
88 return;
89 }
90 *to = '\0';
91 }
92
93
94 /*
95 * prefix -- see if pfx is a prefix of string.
96 */
97
98 int
prefix(const char * pfx,const char * string)99 prefix(const char *pfx, const char *string)
100 {
101 while (*pfx) {
102 if (*pfx++ != *string++)
103 return 0;
104 }
105 return 1;
106 }
107
108
109 /*
110 * Convert a string of digits to an integer, printing an error message on
111 * failure.
112 */
113
114 int
number(const char * s)115 number(const char *s)
116 {
117 char *ep = NULL;
118 intmax_t n;
119
120 if (!is_digit(*s) || ((n = strtoimax(s, &ep, 10)),
121 (ep == NULL || ep == s || *ep != '\0')))
122 error("Invalid number: '%s'", s);
123 if (n < INT_MIN || n > INT_MAX)
124 error("Number out of range: %s", s);
125 return (int)n;
126 }
127
128
129
130 /*
131 * Check for a valid number. This should be elsewhere.
132 */
133
134 int
is_number(const char * p)135 is_number(const char *p)
136 {
137 do {
138 if (! is_digit(*p))
139 return 0;
140 } while (*++p != '\0');
141 return 1;
142 }
143
144 /*
145 * Check a string for common representations of yes/true/...
146 * Default result is false
147 */
148
149 int
boolstr(const char * s)150 boolstr(const char *s)
151 {
152 size_t len;
153
154 if (s == NULL)
155 return 0;
156
157 len = strlen(s);
158 if (len == 0)
159 return 0;
160
161 if (strncasecmp(s, "true", len) == 0 ||
162 strncasecmp(s, "yes", len) == 0 ||
163 (len == 2 && strcasecmp(s, "on") == 0) ||
164 is_digit(*s) || atoi(s) != 0)
165 return 1;
166
167 return 0;
168 }
169