xref: /freebsd/sys/contrib/openzfs/module/os/freebsd/spl/spl_string.c (revision e453e498cbb88570a3ff7b3679de65c88707da95)
1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3  * CDDL HEADER START
4  *
5  * The contents of this file are subject to the terms of the
6  * Common Development and Distribution License (the "License").
7  * You may not use this file except in compliance with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or https://opensource.org/licenses/CDDL-1.0.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  *
22  * $FreeBSD$
23  */
24 /*
25  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
26  * Use is subject to license terms.
27  */
28 
29 #include <sys/types.h>
30 #include <sys/param.h>
31 #include <sys/string.h>
32 #include <sys/kmem.h>
33 #include <sys/stdarg.h>
34 
35 #define	IS_DIGIT(c)	((c) >= '0' && (c) <= '9')
36 
37 #define	IS_ALPHA(c)	\
38 	(((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z'))
39 
40 char *
strpbrk(const char * s,const char * b)41 strpbrk(const char *s, const char *b)
42 {
43 	const char *p;
44 
45 	do {
46 		for (p = b; *p != '\0' && *p != *s; ++p)
47 			;
48 		if (*p != '\0')
49 			return ((char *)s);
50 	} while (*s++);
51 
52 	return (NULL);
53 }
54 
55 /*
56  * Convert a string into a valid C identifier by replacing invalid
57  * characters with '_'.  Also makes sure the string is nul-terminated
58  * and takes up at most n bytes.
59  */
60 void
strident_canon(char * s,size_t n)61 strident_canon(char *s, size_t n)
62 {
63 	char c;
64 	char *end = s + n - 1;
65 
66 	if ((c = *s) == 0)
67 		return;
68 
69 	if (!IS_ALPHA(c) && c != '_')
70 		*s = '_';
71 
72 	while (s < end && ((c = *(++s)) != 0)) {
73 		if (!IS_ALPHA(c) && !IS_DIGIT(c) && c != '_')
74 			*s = '_';
75 	}
76 	*s = 0;
77 }
78 
79 /*
80  * Do not change the length of the returned string; it must be freed
81  * with strfree().
82  */
83 char *
kmem_asprintf(const char * fmt,...)84 kmem_asprintf(const char *fmt, ...)
85 {
86 	int size;
87 	va_list adx;
88 	char *buf;
89 
90 	va_start(adx, fmt);
91 	size = vsnprintf(NULL, 0, fmt, adx) + 1;
92 	va_end(adx);
93 
94 	buf = kmem_alloc(size, KM_SLEEP);
95 
96 	va_start(adx, fmt);
97 	(void) vsnprintf(buf, size, fmt, adx);
98 	va_end(adx);
99 
100 	return (buf);
101 }
102 
103 void
kmem_strfree(char * str)104 kmem_strfree(char *str)
105 {
106 	ASSERT3P(str, !=, NULL);
107 	kmem_free(str, strlen(str) + 1);
108 }
109 
110 /*
111  * kmem_scnprintf() will return the number of characters that it would have
112  * printed whenever it is limited by value of the size variable, rather than
113  * the number of characters that it did print. This can cause misbehavior on
114  * subsequent uses of the return value, so we define a safe version that will
115  * return the number of characters actually printed, minus the NULL format
116  * character.  Subsequent use of this by the safe string functions is safe
117  * whether it is snprintf(), strlcat() or strlcpy().
118  */
119 
120 int
kmem_scnprintf(char * restrict str,size_t size,const char * restrict fmt,...)121 kmem_scnprintf(char *restrict str, size_t size, const char *restrict fmt, ...)
122 {
123 	int n;
124 	va_list ap;
125 
126 	/* Make the 0 case a no-op so that we do not return -1 */
127 	if (size == 0)
128 		return (0);
129 
130 	va_start(ap, fmt);
131 	n = vsnprintf(str, size, fmt, ap);
132 	va_end(ap);
133 
134 	if (n >= size)
135 		n = size - 1;
136 
137 	return (n);
138 }
139