xref: /freebsd/sys/compat/linuxkpi/common/include/linux/string.h (revision 5945da0bc9ac42f531b1079a246eb8ce4f0d63db)
1 /*-
2  * Copyright (c) 2010 Isilon Systems, Inc.
3  * Copyright (c) 2010 iX Systems, Inc.
4  * Copyright (c) 2010 Panasas, Inc.
5  * Copyright (c) 2013-2017 Mellanox Technologies, Ltd.
6  * All rights reserved.
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 unmodified, this list of conditions, and the following
13  *    disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 #ifndef	_LINUXKPI_LINUX_STRING_H_
30 #define	_LINUXKPI_LINUX_STRING_H_
31 
32 #include <sys/ctype.h>
33 
34 #include <linux/array_size.h>
35 #include <linux/types.h>
36 #include <linux/gfp.h>
37 #include <linux/slab.h>
38 #include <linux/uaccess.h>
39 #include <linux/err.h>
40 #include <linux/bitops.h> /* for BITS_PER_LONG */
41 #include <linux/overflow.h>
42 #include <linux/stdarg.h>
43 
44 #include <sys/libkern.h>
45 
46 #define	strnicmp(...) strncasecmp(__VA_ARGS__)
47 
48 static inline int
49 match_string(const char *const *table, int n, const char *key)
50 {
51 	int i;
52 
53 	for (i = 0; i != n && table[i] != NULL; i++) {
54 		if (strcmp(table[i], key) == 0)
55 			return (i);
56 	}
57 	return (-EINVAL);
58 }
59 
60 static inline void *
61 memdup_user(const void *ptr, size_t len)
62 {
63 	void *retval;
64 	int error;
65 
66 	retval = malloc(len, M_KMALLOC, M_WAITOK);
67 	error = linux_copyin(ptr, retval, len);
68 	if (error != 0) {
69 		free(retval, M_KMALLOC);
70 		return (ERR_PTR(error));
71 	}
72 	return (retval);
73 }
74 
75 static inline void *
76 memdup_user_nul(const void *ptr, size_t len)
77 {
78 	char *retval;
79 	int error;
80 
81 	retval = malloc(len + 1, M_KMALLOC, M_WAITOK);
82 	error = linux_copyin(ptr, retval, len);
83 	if (error != 0) {
84 		free(retval, M_KMALLOC);
85 		return (ERR_PTR(error));
86 	}
87 	retval[len] = '\0';
88 	return (retval);
89 }
90 
91 static inline void *
92 memdup_array_user(const void *src, size_t n, size_t size)
93 {
94 	size_t len;
95 
96 	if (check_mul_overflow(n, size, &len))
97 		return (ERR_PTR(-EOVERFLOW));
98 
99 	return (memdup_user(src, len));
100 }
101 
102 static inline void *
103 kmemdup(const void *src, size_t len, gfp_t gfp)
104 {
105 	void *dst;
106 
107 	dst = kmalloc(len, gfp);
108 	if (dst != NULL)
109 		memcpy(dst, src, len);
110 	return (dst);
111 }
112 
113 static inline void *
114 kmemdup_array(const void *src, size_t count, size_t element_size, gfp_t gfp)
115 {
116 	return (kmemdup(src, size_mul(count, element_size), gfp));
117 }
118 
119 /* See slab.h for kvmalloc/kvfree(). */
120 static inline void *
121 kvmemdup(const void *src, size_t len, gfp_t gfp)
122 {
123 	void *dst;
124 
125 	dst = kvmalloc(len, gfp);
126 	if (dst != NULL)
127 		memcpy(dst, src, len);
128 	return (dst);
129 }
130 
131 static inline char *
132 strndup_user(const char __user *ustr, long n)
133 {
134 	if (n < 1)
135 		return (ERR_PTR(-EINVAL));
136 
137 	return (memdup_user_nul(ustr, n - 1));
138 }
139 
140 static inline char *
141 kstrdup(const char *string, gfp_t gfp)
142 {
143 	char *retval;
144 	size_t len;
145 
146 	if (string == NULL)
147 		return (NULL);
148 	len = strlen(string) + 1;
149 	retval = kmalloc(len, gfp);
150 	if (retval != NULL)
151 		memcpy(retval, string, len);
152 	return (retval);
153 }
154 
155 static inline char *
156 kstrndup(const char *string, size_t len, gfp_t gfp)
157 {
158 	char *retval;
159 
160 	if (string == NULL)
161 		return (NULL);
162 	retval = kmalloc(len + 1, gfp);
163 	if (retval != NULL)
164 		strncpy(retval, string, len);
165 	return (retval);
166 }
167 
168 static inline const char *
169 kstrdup_const(const char *src, gfp_t gfp)
170 {
171 	return (kmemdup(src, strlen(src) + 1, gfp));
172 }
173 
174 static inline char *
175 skip_spaces(const char *str)
176 {
177 	while (isspace(*str))
178 		++str;
179 	return (__DECONST(char *, str));
180 }
181 
182 /*
183  * This function trims whitespaces at the end of a string and returns a pointer
184  * to the first non-whitespace character.
185  */
186 static inline char *
187 strim(char *str)
188 {
189 	char *end;
190 
191 	end = str + strlen(str);
192 	while (end >= str && (*end == '\0' || isspace(*end))) {
193 		*end = '\0';
194 		end--;
195 	}
196 
197 	return (skip_spaces(str));
198 }
199 
200 static inline void *
201 memchr_inv(const void *start, int c, size_t length)
202 {
203 	const u8 *ptr;
204 	const u8 *end;
205 	u8 ch;
206 
207 	ch = c;
208 	ptr = start;
209 	end = ptr + length;
210 
211 	while (ptr != end) {
212 		if (*ptr != ch)
213 			return (__DECONST(void *, ptr));
214 		ptr++;
215 	}
216 	return (NULL);
217 }
218 
219 static inline bool
220 mem_is_zero(const void *start, size_t length)
221 {
222 	return (memchr_inv(start, 0, length) == NULL);
223 }
224 
225 static inline size_t
226 str_has_prefix(const char *str, const char *prefix)
227 {
228 	size_t len;
229 
230 	len = strlen(prefix);
231 	return (strncmp(str, prefix, len) == 0 ? len : 0);
232 }
233 
234 static inline char *
235 strreplace(char *str, char old, char new)
236 {
237 	char *p;
238 
239 	p = strchrnul(str, old);
240 	while (p != NULL && *p != '\0') {
241 		*p = new;
242 		p = strchrnul(str, old);
243 	}
244 	return (p);
245 }
246 
247 static inline ssize_t
248 strscpy(char* dst, const char* src, size_t len)
249 {
250 	size_t i;
251 
252 	if (len <= INT_MAX) {
253 		for (i = 0; i < len; i++)
254 			if ('\0' == (dst[i] = src[i]))
255 				return ((ssize_t)i);
256 		if (i != 0)
257 			dst[--i] = '\0';
258 	}
259 
260 	return (-E2BIG);
261 }
262 
263 static inline ssize_t
264 strscpy_pad(char* dst, const char* src, size_t len)
265 {
266 
267 	bzero(dst, len);
268 
269 	return (strscpy(dst, src, len));
270 }
271 
272 static inline char *
273 strnchr(const char *cp, size_t n, int ch)
274 {
275 	char *p;
276 
277 	for (p = __DECONST(char *, cp); n--; ++p) {
278 		if (*p == ch)
279 			return (p);
280 		if (*p == '\0')
281 			break;
282 	}
283 
284 	return (NULL);
285 }
286 
287 static inline void *
288 memset32(uint32_t *b, uint32_t c, size_t len)
289 {
290 	uint32_t *dst = b;
291 
292 	while (len--)
293 		*dst++ = c;
294 	return (b);
295 }
296 
297 static inline void *
298 memset64(uint64_t *b, uint64_t c, size_t len)
299 {
300 	uint64_t *dst = b;
301 
302 	while (len--)
303 		*dst++ = c;
304 	return (b);
305 }
306 
307 static inline void *
308 memset_p(void **p, void *v, size_t n)
309 {
310 
311 	if (BITS_PER_LONG == 32)
312 		return (memset32((uint32_t *)p, (uintptr_t)v, n));
313 	else
314 		return (memset64((uint64_t *)p, (uintptr_t)v, n));
315 }
316 
317 static inline void
318 memcpy_and_pad(void *dst, size_t dstlen, const void *src, size_t len, int ch)
319 {
320 
321 	if (len >= dstlen) {
322 		memcpy(dst, src, dstlen);
323 	} else {
324 		memcpy(dst, src, len);
325 		/* Pad with given padding character. */
326 		memset((char *)dst + len, ch, dstlen - len);
327 	}
328 }
329 
330 #define strtomem(dst, src)	do {					\
331 	size_t dstlen = ARRAY_SIZE(dst);				\
332 	size_t srclen = __builtin_object_size(src, 1);			\
333 	srclen = MIN(srclen, dstlen);					\
334 	srclen = strnlen(src, srclen);					\
335 	memcpy(dst, src, srclen);					\
336 } while (0)
337 
338 #define strtomem_pad(dst, src, pad)	do {				\
339 	size_t dstlen = ARRAY_SIZE(dst);				\
340 	size_t srclen = __builtin_object_size(src, 1);			\
341 	srclen = MIN(srclen, dstlen);					\
342 	srclen = strnlen(src, srclen);					\
343 	memcpy_and_pad(dst, dstlen, src, srclen, pad);			\
344 } while (0)
345 
346 #define	memset_startat(ptr, bytepat, smember)				\
347 ({									\
348 	uint8_t *_ptr = (uint8_t *)(ptr);				\
349 	int _c = (int)(bytepat);					\
350 	size_t _o = offsetof(typeof(*(ptr)), smember);			\
351 	memset(_ptr + _o, _c, sizeof(*(ptr)) - _o);			\
352 })
353 
354 #define	memset_after(ptr, bytepat, smember)				\
355 ({									\
356 	uint8_t *_ptr = (uint8_t *)(ptr);				\
357 	int _c = (int)(bytepat);					\
358 	size_t _o = offsetofend(typeof(*(ptr)), smember);		\
359 	memset(_ptr + _o, _c, sizeof(*(ptr)) - _o);			\
360 })
361 
362 static inline void
363 memzero_explicit(void *p, size_t s)
364 {
365 	memset(p, 0, s);
366 	__asm__ __volatile__("": :"r"(p) :"memory");
367 }
368 
369 #endif	/* _LINUXKPI_LINUX_STRING_H_ */
370