xref: /freebsd/sys/contrib/openzfs/module/os/freebsd/spl/spl_string.c (revision 22649d4dba730d46244fd2dff4fd174903c8379f)
1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3  * This file and its contents are supplied under the terms of the
4  * Common Development and Distribution License ("CDDL"), version 1.0.
5  * You may only use this file in accordance with the terms of version
6  * 1.0 of the CDDL.
7  *
8  * A full copy of the text of the CDDL should have accompanied this
9  * source.  A copy of the CDDL is also available via the Internet at
10  * https://opensource.org/license/CDDL-1.0.
11  *
12  * $FreeBSD$
13  */
14 /*
15  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
16  * Use is subject to license terms.
17  */
18 
19 #include <sys/types.h>
20 #include <sys/param.h>
21 #include <sys/string.h>
22 #include <sys/kmem.h>
23 #include <sys/stdarg.h>
24 
25 #define	IS_DIGIT(c)	((c) >= '0' && (c) <= '9')
26 
27 #define	IS_ALPHA(c)	\
28 	(((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z'))
29 
30 char *
strpbrk(const char * s,const char * b)31 strpbrk(const char *s, const char *b)
32 {
33 	const char *p;
34 
35 	do {
36 		for (p = b; *p != '\0' && *p != *s; ++p)
37 			;
38 		if (*p != '\0')
39 			return ((char *)s);
40 	} while (*s++);
41 
42 	return (NULL);
43 }
44 
45 /*
46  * Convert a string into a valid C identifier by replacing invalid
47  * characters with '_'.  Also makes sure the string is nul-terminated
48  * and takes up at most n bytes.
49  */
50 void
strident_canon(char * s,size_t n)51 strident_canon(char *s, size_t n)
52 {
53 	char c;
54 	char *end = s + n - 1;
55 
56 	if ((c = *s) == 0)
57 		return;
58 
59 	if (!IS_ALPHA(c) && c != '_')
60 		*s = '_';
61 
62 	while (s < end && ((c = *(++s)) != 0)) {
63 		if (!IS_ALPHA(c) && !IS_DIGIT(c) && c != '_')
64 			*s = '_';
65 	}
66 	*s = 0;
67 }
68 
69 /*
70  * Do not change the length of the returned string; it must be freed
71  * with strfree().
72  */
73 char *
kmem_asprintf(const char * fmt,...)74 kmem_asprintf(const char *fmt, ...)
75 {
76 	int size;
77 	va_list adx;
78 	char *buf;
79 
80 	va_start(adx, fmt);
81 	size = vsnprintf(NULL, 0, fmt, adx) + 1;
82 	va_end(adx);
83 
84 	buf = kmem_alloc(size, KM_SLEEP);
85 
86 	va_start(adx, fmt);
87 	(void) vsnprintf(buf, size, fmt, adx);
88 	va_end(adx);
89 
90 	return (buf);
91 }
92 
93 void
kmem_strfree(char * str)94 kmem_strfree(char *str)
95 {
96 	ASSERT3P(str, !=, NULL);
97 	kmem_free(str, strlen(str) + 1);
98 }
99 
100 /*
101  * kmem_scnprintf() will return the number of characters that it would have
102  * printed whenever it is limited by value of the size variable, rather than
103  * the number of characters that it did print. This can cause misbehavior on
104  * subsequent uses of the return value, so we define a safe version that will
105  * return the number of characters actually printed, minus the NULL format
106  * character.  Subsequent use of this by the safe string functions is safe
107  * whether it is snprintf(), strlcat() or strlcpy().
108  */
109 
110 int
kmem_scnprintf(char * restrict str,size_t size,const char * restrict fmt,...)111 kmem_scnprintf(char *restrict str, size_t size, const char *restrict fmt, ...)
112 {
113 	int n;
114 	va_list ap;
115 
116 	/* Make the 0 case a no-op so that we do not return -1 */
117 	if (size == 0)
118 		return (0);
119 
120 	va_start(ap, fmt);
121 	n = vsnprintf(str, size, fmt, ap);
122 	va_end(ap);
123 
124 	if (n >= size)
125 		n = size - 1;
126 
127 	return (n);
128 }
129