]>
Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * linux/lib/string.c | |
4 | * | |
5 | * Copyright (C) 1991, 1992 Linus Torvalds | |
6 | */ | |
7 | ||
8 | /* | |
9 | * stupid library routines.. The optimized versions should generally be found | |
10 | * as inline code in <asm-xx/string.h> | |
11 | * | |
12 | * These are buggy as well.. | |
13 | * | |
14 | * * Fri Jun 25 1999, Ingo Oeser <ioe@informatik.tu-chemnitz.de> | |
15 | * - Added strsep() which will replace strtok() soon (because strsep() is | |
16 | * reentrant and should be faster). Use only strsep() in new code, please. | |
17 | * | |
18 | * * Sat Feb 09 2002, Jason Thomas <jason@topic.com.au>, | |
19 | * Matthew Hawkins <matt@mh.dropbear.id.au> | |
20 | * - Kissed strtok() goodbye | |
21 | */ | |
22 | ||
23 | #include <linux/types.h> | |
24 | #include <linux/string.h> | |
25 | #include <linux/ctype.h> | |
8bc3bcc9 PG |
26 | #include <linux/kernel.h> |
27 | #include <linux/export.h> | |
50af5ead | 28 | #include <linux/bug.h> |
8bc3bcc9 | 29 | #include <linux/errno.h> |
ce76d938 | 30 | #include <linux/slab.h> |
1da177e4 | 31 | |
30035e45 CM |
32 | #include <asm/byteorder.h> |
33 | #include <asm/word-at-a-time.h> | |
34 | #include <asm/page.h> | |
35 | ||
cd514e72 | 36 | #ifndef __HAVE_ARCH_STRNCASECMP |
1da177e4 | 37 | /** |
cd514e72 | 38 | * strncasecmp - Case insensitive, length-limited string comparison |
1da177e4 LT |
39 | * @s1: One string |
40 | * @s2: The other string | |
41 | * @len: the maximum number of characters to compare | |
42 | */ | |
cd514e72 | 43 | int strncasecmp(const char *s1, const char *s2, size_t len) |
1da177e4 LT |
44 | { |
45 | /* Yes, Virginia, it had better be unsigned */ | |
46 | unsigned char c1, c2; | |
47 | ||
a11d2b64 AGR |
48 | if (!len) |
49 | return 0; | |
50 | ||
51 | do { | |
52 | c1 = *s1++; | |
53 | c2 = *s2++; | |
54 | if (!c1 || !c2) | |
55 | break; | |
56 | if (c1 == c2) | |
57 | continue; | |
58 | c1 = tolower(c1); | |
59 | c2 = tolower(c2); | |
60 | if (c1 != c2) | |
61 | break; | |
62 | } while (--len); | |
1da177e4 LT |
63 | return (int)c1 - (int)c2; |
64 | } | |
cd514e72 RV |
65 | EXPORT_SYMBOL(strncasecmp); |
66 | #endif | |
1da177e4 | 67 | |
ded220bd DM |
68 | #ifndef __HAVE_ARCH_STRCASECMP |
69 | int strcasecmp(const char *s1, const char *s2) | |
70 | { | |
71 | int c1, c2; | |
72 | ||
73 | do { | |
74 | c1 = tolower(*s1++); | |
75 | c2 = tolower(*s2++); | |
76 | } while (c1 == c2 && c1 != 0); | |
77 | return c1 - c2; | |
78 | } | |
79 | EXPORT_SYMBOL(strcasecmp); | |
80 | #endif | |
81 | ||
1da177e4 LT |
82 | #ifndef __HAVE_ARCH_STRCPY |
83 | /** | |
84 | * strcpy - Copy a %NUL terminated string | |
85 | * @dest: Where to copy the string to | |
86 | * @src: Where to copy the string from | |
87 | */ | |
0c28130b | 88 | #undef strcpy |
51a0f0f6 | 89 | char *strcpy(char *dest, const char *src) |
1da177e4 LT |
90 | { |
91 | char *tmp = dest; | |
92 | ||
93 | while ((*dest++ = *src++) != '\0') | |
94 | /* nothing */; | |
95 | return tmp; | |
96 | } | |
97 | EXPORT_SYMBOL(strcpy); | |
98 | #endif | |
99 | ||
100 | #ifndef __HAVE_ARCH_STRNCPY | |
101 | /** | |
0046dd9f | 102 | * strncpy - Copy a length-limited, C-string |
1da177e4 LT |
103 | * @dest: Where to copy the string to |
104 | * @src: Where to copy the string from | |
105 | * @count: The maximum number of bytes to copy | |
106 | * | |
107 | * The result is not %NUL-terminated if the source exceeds | |
108 | * @count bytes. | |
25279526 | 109 | * |
110 | * In the case where the length of @src is less than that of | |
111 | * count, the remainder of @dest will be padded with %NUL. | |
112 | * | |
1da177e4 | 113 | */ |
51a0f0f6 | 114 | char *strncpy(char *dest, const char *src, size_t count) |
1da177e4 LT |
115 | { |
116 | char *tmp = dest; | |
117 | ||
118 | while (count) { | |
51a0f0f6 JJ |
119 | if ((*tmp = *src) != 0) |
120 | src++; | |
1da177e4 LT |
121 | tmp++; |
122 | count--; | |
123 | } | |
124 | return dest; | |
125 | } | |
126 | EXPORT_SYMBOL(strncpy); | |
127 | #endif | |
128 | ||
129 | #ifndef __HAVE_ARCH_STRLCPY | |
130 | /** | |
0046dd9f | 131 | * strlcpy - Copy a C-string into a sized buffer |
1da177e4 LT |
132 | * @dest: Where to copy the string to |
133 | * @src: Where to copy the string from | |
134 | * @size: size of destination buffer | |
135 | * | |
0e056eb5 | 136 | * Compatible with ``*BSD``: the result is always a valid |
1da177e4 LT |
137 | * NUL-terminated string that fits in the buffer (unless, |
138 | * of course, the buffer size is zero). It does not pad | |
139 | * out the result like strncpy() does. | |
140 | */ | |
141 | size_t strlcpy(char *dest, const char *src, size_t size) | |
142 | { | |
143 | size_t ret = strlen(src); | |
144 | ||
145 | if (size) { | |
51a0f0f6 | 146 | size_t len = (ret >= size) ? size - 1 : ret; |
1da177e4 LT |
147 | memcpy(dest, src, len); |
148 | dest[len] = '\0'; | |
149 | } | |
150 | return ret; | |
151 | } | |
152 | EXPORT_SYMBOL(strlcpy); | |
153 | #endif | |
154 | ||
30035e45 CM |
155 | #ifndef __HAVE_ARCH_STRSCPY |
156 | /** | |
157 | * strscpy - Copy a C-string into a sized buffer | |
158 | * @dest: Where to copy the string to | |
159 | * @src: Where to copy the string from | |
160 | * @count: Size of destination buffer | |
161 | * | |
458a3bf8 TH |
162 | * Copy the string, or as much of it as fits, into the dest buffer. The |
163 | * behavior is undefined if the string buffers overlap. The destination | |
164 | * buffer is always NUL terminated, unless it's zero-sized. | |
30035e45 CM |
165 | * |
166 | * Preferred to strlcpy() since the API doesn't require reading memory | |
167 | * from the src string beyond the specified "count" bytes, and since | |
168 | * the return value is easier to error-check than strlcpy()'s. | |
169 | * In addition, the implementation is robust to the string changing out | |
170 | * from underneath it, unlike the current strlcpy() implementation. | |
171 | * | |
172 | * Preferred to strncpy() since it always returns a valid string, and | |
173 | * doesn't unnecessarily force the tail of the destination buffer to be | |
458a3bf8 TH |
174 | * zeroed. If zeroing is desired please use strscpy_pad(). |
175 | * | |
917cda27 JP |
176 | * Returns: |
177 | * * The number of characters copied (not including the trailing %NUL) | |
178 | * * -E2BIG if count is 0 or @src was truncated. | |
30035e45 CM |
179 | */ |
180 | ssize_t strscpy(char *dest, const char *src, size_t count) | |
181 | { | |
182 | const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS; | |
183 | size_t max = count; | |
184 | long res = 0; | |
185 | ||
9a156466 | 186 | if (count == 0 || WARN_ON_ONCE(count > INT_MAX)) |
30035e45 CM |
187 | return -E2BIG; |
188 | ||
189 | #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS | |
190 | /* | |
191 | * If src is unaligned, don't cross a page boundary, | |
192 | * since we don't know if the next page is mapped. | |
193 | */ | |
194 | if ((long)src & (sizeof(long) - 1)) { | |
195 | size_t limit = PAGE_SIZE - ((long)src & (PAGE_SIZE - 1)); | |
196 | if (limit < max) | |
197 | max = limit; | |
198 | } | |
199 | #else | |
200 | /* If src or dest is unaligned, don't do word-at-a-time. */ | |
201 | if (((long) dest | (long) src) & (sizeof(long) - 1)) | |
202 | max = 0; | |
203 | #endif | |
204 | ||
205 | while (max >= sizeof(unsigned long)) { | |
206 | unsigned long c, data; | |
207 | ||
1a3241ff | 208 | c = read_word_at_a_time(src+res); |
30035e45 CM |
209 | if (has_zero(c, &data, &constants)) { |
210 | data = prep_zero_mask(c, data, &constants); | |
211 | data = create_zero_mask(data); | |
990486c8 | 212 | *(unsigned long *)(dest+res) = c & zero_bytemask(data); |
30035e45 CM |
213 | return res + find_zero(data); |
214 | } | |
990486c8 | 215 | *(unsigned long *)(dest+res) = c; |
30035e45 CM |
216 | res += sizeof(unsigned long); |
217 | count -= sizeof(unsigned long); | |
218 | max -= sizeof(unsigned long); | |
219 | } | |
220 | ||
221 | while (count) { | |
222 | char c; | |
223 | ||
224 | c = src[res]; | |
225 | dest[res] = c; | |
226 | if (!c) | |
227 | return res; | |
228 | res++; | |
229 | count--; | |
230 | } | |
231 | ||
232 | /* Hit buffer length without finding a NUL; force NUL-termination. */ | |
233 | if (res) | |
234 | dest[res-1] = '\0'; | |
235 | ||
236 | return -E2BIG; | |
237 | } | |
238 | EXPORT_SYMBOL(strscpy); | |
239 | #endif | |
240 | ||
458a3bf8 TH |
241 | /** |
242 | * strscpy_pad() - Copy a C-string into a sized buffer | |
243 | * @dest: Where to copy the string to | |
244 | * @src: Where to copy the string from | |
245 | * @count: Size of destination buffer | |
246 | * | |
247 | * Copy the string, or as much of it as fits, into the dest buffer. The | |
248 | * behavior is undefined if the string buffers overlap. The destination | |
249 | * buffer is always %NUL terminated, unless it's zero-sized. | |
250 | * | |
251 | * If the source string is shorter than the destination buffer, zeros | |
252 | * the tail of the destination buffer. | |
253 | * | |
254 | * For full explanation of why you may want to consider using the | |
255 | * 'strscpy' functions please see the function docstring for strscpy(). | |
256 | * | |
917cda27 JP |
257 | * Returns: |
258 | * * The number of characters copied (not including the trailing %NUL) | |
259 | * * -E2BIG if count is 0 or @src was truncated. | |
458a3bf8 TH |
260 | */ |
261 | ssize_t strscpy_pad(char *dest, const char *src, size_t count) | |
262 | { | |
263 | ssize_t written; | |
264 | ||
265 | written = strscpy(dest, src, count); | |
266 | if (written < 0 || written == count - 1) | |
267 | return written; | |
268 | ||
269 | memset(dest + written + 1, 0, count - written - 1); | |
270 | ||
271 | return written; | |
272 | } | |
273 | EXPORT_SYMBOL(strscpy_pad); | |
274 | ||
1e1b6d63 ND |
275 | /** |
276 | * stpcpy - copy a string from src to dest returning a pointer to the new end | |
277 | * of dest, including src's %NUL-terminator. May overrun dest. | |
278 | * @dest: pointer to end of string being copied into. Must be large enough | |
279 | * to receive copy. | |
280 | * @src: pointer to the beginning of string being copied from. Must not overlap | |
281 | * dest. | |
282 | * | |
283 | * stpcpy differs from strcpy in a key way: the return value is a pointer | |
284 | * to the new %NUL-terminating character in @dest. (For strcpy, the return | |
285 | * value is a pointer to the start of @dest). This interface is considered | |
286 | * unsafe as it doesn't perform bounds checking of the inputs. As such it's | |
287 | * not recommended for usage. Instead, its definition is provided in case | |
288 | * the compiler lowers other libcalls to stpcpy. | |
289 | */ | |
290 | char *stpcpy(char *__restrict__ dest, const char *__restrict__ src); | |
291 | char *stpcpy(char *__restrict__ dest, const char *__restrict__ src) | |
292 | { | |
293 | while ((*dest++ = *src++) != '\0') | |
294 | /* nothing */; | |
295 | return --dest; | |
296 | } | |
297 | EXPORT_SYMBOL(stpcpy); | |
298 | ||
1da177e4 LT |
299 | #ifndef __HAVE_ARCH_STRCAT |
300 | /** | |
301 | * strcat - Append one %NUL-terminated string to another | |
302 | * @dest: The string to be appended to | |
303 | * @src: The string to append to it | |
304 | */ | |
0c28130b | 305 | #undef strcat |
51a0f0f6 | 306 | char *strcat(char *dest, const char *src) |
1da177e4 LT |
307 | { |
308 | char *tmp = dest; | |
309 | ||
310 | while (*dest) | |
311 | dest++; | |
312 | while ((*dest++ = *src++) != '\0') | |
313 | ; | |
1da177e4 LT |
314 | return tmp; |
315 | } | |
316 | EXPORT_SYMBOL(strcat); | |
317 | #endif | |
318 | ||
319 | #ifndef __HAVE_ARCH_STRNCAT | |
320 | /** | |
0046dd9f | 321 | * strncat - Append a length-limited, C-string to another |
1da177e4 LT |
322 | * @dest: The string to be appended to |
323 | * @src: The string to append to it | |
324 | * @count: The maximum numbers of bytes to copy | |
325 | * | |
72fd4a35 | 326 | * Note that in contrast to strncpy(), strncat() ensures the result is |
1da177e4 LT |
327 | * terminated. |
328 | */ | |
51a0f0f6 | 329 | char *strncat(char *dest, const char *src, size_t count) |
1da177e4 LT |
330 | { |
331 | char *tmp = dest; | |
332 | ||
333 | if (count) { | |
334 | while (*dest) | |
335 | dest++; | |
336 | while ((*dest++ = *src++) != 0) { | |
337 | if (--count == 0) { | |
338 | *dest = '\0'; | |
339 | break; | |
340 | } | |
341 | } | |
342 | } | |
1da177e4 LT |
343 | return tmp; |
344 | } | |
345 | EXPORT_SYMBOL(strncat); | |
346 | #endif | |
347 | ||
348 | #ifndef __HAVE_ARCH_STRLCAT | |
349 | /** | |
0046dd9f | 350 | * strlcat - Append a length-limited, C-string to another |
1da177e4 LT |
351 | * @dest: The string to be appended to |
352 | * @src: The string to append to it | |
353 | * @count: The size of the destination buffer. | |
354 | */ | |
355 | size_t strlcat(char *dest, const char *src, size_t count) | |
356 | { | |
357 | size_t dsize = strlen(dest); | |
358 | size_t len = strlen(src); | |
359 | size_t res = dsize + len; | |
360 | ||
361 | /* This would be a bug */ | |
362 | BUG_ON(dsize >= count); | |
363 | ||
364 | dest += dsize; | |
365 | count -= dsize; | |
366 | if (len >= count) | |
367 | len = count-1; | |
368 | memcpy(dest, src, len); | |
369 | dest[len] = 0; | |
370 | return res; | |
371 | } | |
372 | EXPORT_SYMBOL(strlcat); | |
373 | #endif | |
374 | ||
375 | #ifndef __HAVE_ARCH_STRCMP | |
376 | /** | |
377 | * strcmp - Compare two strings | |
378 | * @cs: One string | |
379 | * @ct: Another string | |
380 | */ | |
0c28130b | 381 | #undef strcmp |
51a0f0f6 | 382 | int strcmp(const char *cs, const char *ct) |
1da177e4 | 383 | { |
a414f01a | 384 | unsigned char c1, c2; |
1da177e4 LT |
385 | |
386 | while (1) { | |
a414f01a LT |
387 | c1 = *cs++; |
388 | c2 = *ct++; | |
389 | if (c1 != c2) | |
390 | return c1 < c2 ? -1 : 1; | |
391 | if (!c1) | |
1da177e4 LT |
392 | break; |
393 | } | |
a414f01a | 394 | return 0; |
1da177e4 LT |
395 | } |
396 | EXPORT_SYMBOL(strcmp); | |
397 | #endif | |
398 | ||
399 | #ifndef __HAVE_ARCH_STRNCMP | |
400 | /** | |
401 | * strncmp - Compare two length-limited strings | |
402 | * @cs: One string | |
403 | * @ct: Another string | |
404 | * @count: The maximum number of bytes to compare | |
405 | */ | |
51a0f0f6 | 406 | int strncmp(const char *cs, const char *ct, size_t count) |
1da177e4 | 407 | { |
a414f01a | 408 | unsigned char c1, c2; |
1da177e4 LT |
409 | |
410 | while (count) { | |
a414f01a LT |
411 | c1 = *cs++; |
412 | c2 = *ct++; | |
413 | if (c1 != c2) | |
414 | return c1 < c2 ? -1 : 1; | |
415 | if (!c1) | |
1da177e4 LT |
416 | break; |
417 | count--; | |
418 | } | |
a414f01a | 419 | return 0; |
1da177e4 LT |
420 | } |
421 | EXPORT_SYMBOL(strncmp); | |
422 | #endif | |
423 | ||
424 | #ifndef __HAVE_ARCH_STRCHR | |
425 | /** | |
426 | * strchr - Find the first occurrence of a character in a string | |
427 | * @s: The string to be searched | |
428 | * @c: The character to search for | |
b0975710 PR |
429 | * |
430 | * Note that the %NUL-terminator is considered part of the string, and can | |
431 | * be searched for. | |
1da177e4 | 432 | */ |
51a0f0f6 | 433 | char *strchr(const char *s, int c) |
1da177e4 | 434 | { |
51a0f0f6 | 435 | for (; *s != (char)c; ++s) |
1da177e4 LT |
436 | if (*s == '\0') |
437 | return NULL; | |
51a0f0f6 | 438 | return (char *)s; |
1da177e4 LT |
439 | } |
440 | EXPORT_SYMBOL(strchr); | |
441 | #endif | |
442 | ||
11d200e9 GL |
443 | #ifndef __HAVE_ARCH_STRCHRNUL |
444 | /** | |
445 | * strchrnul - Find and return a character in a string, or end of string | |
446 | * @s: The string to be searched | |
447 | * @c: The character to search for | |
448 | * | |
449 | * Returns pointer to first occurrence of 'c' in s. If c is not found, then | |
450 | * return a pointer to the null byte at the end of s. | |
451 | */ | |
452 | char *strchrnul(const char *s, int c) | |
453 | { | |
454 | while (*s && *s != (char)c) | |
455 | s++; | |
456 | return (char *)s; | |
457 | } | |
458 | EXPORT_SYMBOL(strchrnul); | |
459 | #endif | |
460 | ||
0bee0cec YN |
461 | /** |
462 | * strnchrnul - Find and return a character in a length limited string, | |
463 | * or end of string | |
464 | * @s: The string to be searched | |
465 | * @count: The number of characters to be searched | |
466 | * @c: The character to search for | |
467 | * | |
468 | * Returns pointer to the first occurrence of 'c' in s. If c is not found, | |
469 | * then return a pointer to the last character of the string. | |
470 | */ | |
471 | char *strnchrnul(const char *s, size_t count, int c) | |
472 | { | |
473 | while (count-- && *s && *s != (char)c) | |
474 | s++; | |
475 | return (char *)s; | |
476 | } | |
477 | ||
1da177e4 LT |
478 | #ifndef __HAVE_ARCH_STRRCHR |
479 | /** | |
480 | * strrchr - Find the last occurrence of a character in a string | |
481 | * @s: The string to be searched | |
482 | * @c: The character to search for | |
483 | */ | |
51a0f0f6 | 484 | char *strrchr(const char *s, int c) |
1da177e4 | 485 | { |
8da53d45 RV |
486 | const char *last = NULL; |
487 | do { | |
488 | if (*s == (char)c) | |
489 | last = s; | |
490 | } while (*s++); | |
491 | return (char *)last; | |
1da177e4 LT |
492 | } |
493 | EXPORT_SYMBOL(strrchr); | |
494 | #endif | |
495 | ||
496 | #ifndef __HAVE_ARCH_STRNCHR | |
497 | /** | |
498 | * strnchr - Find a character in a length limited string | |
499 | * @s: The string to be searched | |
500 | * @count: The number of characters to be searched | |
501 | * @c: The character to search for | |
b0975710 PR |
502 | * |
503 | * Note that the %NUL-terminator is considered part of the string, and can | |
504 | * be searched for. | |
1da177e4 LT |
505 | */ |
506 | char *strnchr(const char *s, size_t count, int c) | |
507 | { | |
b0975710 | 508 | while (count--) { |
51a0f0f6 JJ |
509 | if (*s == (char)c) |
510 | return (char *)s; | |
b0975710 PR |
511 | if (*s++ == '\0') |
512 | break; | |
513 | } | |
1da177e4 LT |
514 | return NULL; |
515 | } | |
516 | EXPORT_SYMBOL(strnchr); | |
517 | #endif | |
518 | ||
f653398c | 519 | /** |
a6cd13f3 RD |
520 | * skip_spaces - Removes leading whitespace from @str. |
521 | * @str: The string to be stripped. | |
f653398c | 522 | * |
a6cd13f3 | 523 | * Returns a pointer to the first non-whitespace character in @str. |
f653398c AGR |
524 | */ |
525 | char *skip_spaces(const char *str) | |
526 | { | |
527 | while (isspace(*str)) | |
528 | ++str; | |
529 | return (char *)str; | |
530 | } | |
531 | EXPORT_SYMBOL(skip_spaces); | |
532 | ||
481fad48 | 533 | /** |
ca54cb8c | 534 | * strim - Removes leading and trailing whitespace from @s. |
481fad48 PE |
535 | * @s: The string to be stripped. |
536 | * | |
537 | * Note that the first trailing whitespace is replaced with a %NUL-terminator | |
538 | * in the given string @s. Returns a pointer to the first non-whitespace | |
539 | * character in @s. | |
540 | */ | |
ca54cb8c | 541 | char *strim(char *s) |
481fad48 PE |
542 | { |
543 | size_t size; | |
544 | char *end; | |
545 | ||
546 | size = strlen(s); | |
481fad48 PE |
547 | if (!size) |
548 | return s; | |
549 | ||
550 | end = s + size - 1; | |
6e6d9fa6 | 551 | while (end >= s && isspace(*end)) |
481fad48 PE |
552 | end--; |
553 | *(end + 1) = '\0'; | |
554 | ||
66f6958e | 555 | return skip_spaces(s); |
481fad48 | 556 | } |
ca54cb8c | 557 | EXPORT_SYMBOL(strim); |
481fad48 | 558 | |
1da177e4 LT |
559 | #ifndef __HAVE_ARCH_STRLEN |
560 | /** | |
561 | * strlen - Find the length of a string | |
562 | * @s: The string to be sized | |
563 | */ | |
51a0f0f6 | 564 | size_t strlen(const char *s) |
1da177e4 LT |
565 | { |
566 | const char *sc; | |
567 | ||
568 | for (sc = s; *sc != '\0'; ++sc) | |
569 | /* nothing */; | |
570 | return sc - s; | |
571 | } | |
572 | EXPORT_SYMBOL(strlen); | |
573 | #endif | |
574 | ||
575 | #ifndef __HAVE_ARCH_STRNLEN | |
576 | /** | |
577 | * strnlen - Find the length of a length-limited string | |
578 | * @s: The string to be sized | |
579 | * @count: The maximum number of bytes to search | |
580 | */ | |
51a0f0f6 | 581 | size_t strnlen(const char *s, size_t count) |
1da177e4 LT |
582 | { |
583 | const char *sc; | |
584 | ||
585 | for (sc = s; count-- && *sc != '\0'; ++sc) | |
586 | /* nothing */; | |
587 | return sc - s; | |
588 | } | |
589 | EXPORT_SYMBOL(strnlen); | |
590 | #endif | |
591 | ||
592 | #ifndef __HAVE_ARCH_STRSPN | |
593 | /** | |
72fd4a35 | 594 | * strspn - Calculate the length of the initial substring of @s which only contain letters in @accept |
1da177e4 LT |
595 | * @s: The string to be searched |
596 | * @accept: The string to search for | |
597 | */ | |
598 | size_t strspn(const char *s, const char *accept) | |
599 | { | |
600 | const char *p; | |
601 | const char *a; | |
602 | size_t count = 0; | |
603 | ||
604 | for (p = s; *p != '\0'; ++p) { | |
605 | for (a = accept; *a != '\0'; ++a) { | |
606 | if (*p == *a) | |
607 | break; | |
608 | } | |
609 | if (*a == '\0') | |
610 | return count; | |
611 | ++count; | |
612 | } | |
1da177e4 LT |
613 | return count; |
614 | } | |
615 | ||
616 | EXPORT_SYMBOL(strspn); | |
617 | #endif | |
618 | ||
8833d328 | 619 | #ifndef __HAVE_ARCH_STRCSPN |
1da177e4 | 620 | /** |
72fd4a35 | 621 | * strcspn - Calculate the length of the initial substring of @s which does not contain letters in @reject |
1da177e4 LT |
622 | * @s: The string to be searched |
623 | * @reject: The string to avoid | |
624 | */ | |
625 | size_t strcspn(const char *s, const char *reject) | |
626 | { | |
627 | const char *p; | |
628 | const char *r; | |
629 | size_t count = 0; | |
630 | ||
631 | for (p = s; *p != '\0'; ++p) { | |
632 | for (r = reject; *r != '\0'; ++r) { | |
633 | if (*p == *r) | |
634 | return count; | |
635 | } | |
636 | ++count; | |
637 | } | |
1da177e4 | 638 | return count; |
51a0f0f6 | 639 | } |
1da177e4 | 640 | EXPORT_SYMBOL(strcspn); |
8833d328 | 641 | #endif |
1da177e4 LT |
642 | |
643 | #ifndef __HAVE_ARCH_STRPBRK | |
644 | /** | |
645 | * strpbrk - Find the first occurrence of a set of characters | |
646 | * @cs: The string to be searched | |
647 | * @ct: The characters to search for | |
648 | */ | |
51a0f0f6 | 649 | char *strpbrk(const char *cs, const char *ct) |
1da177e4 | 650 | { |
51a0f0f6 | 651 | const char *sc1, *sc2; |
1da177e4 | 652 | |
51a0f0f6 JJ |
653 | for (sc1 = cs; *sc1 != '\0'; ++sc1) { |
654 | for (sc2 = ct; *sc2 != '\0'; ++sc2) { | |
1da177e4 | 655 | if (*sc1 == *sc2) |
51a0f0f6 | 656 | return (char *)sc1; |
1da177e4 LT |
657 | } |
658 | } | |
659 | return NULL; | |
660 | } | |
894b5779 | 661 | EXPORT_SYMBOL(strpbrk); |
1da177e4 LT |
662 | #endif |
663 | ||
664 | #ifndef __HAVE_ARCH_STRSEP | |
665 | /** | |
666 | * strsep - Split a string into tokens | |
667 | * @s: The string to be searched | |
668 | * @ct: The characters to search for | |
669 | * | |
670 | * strsep() updates @s to point after the token, ready for the next call. | |
671 | * | |
672 | * It returns empty tokens, too, behaving exactly like the libc function | |
673 | * of that name. In fact, it was stolen from glibc2 and de-fancy-fied. | |
674 | * Same semantics, slimmer shape. ;) | |
675 | */ | |
51a0f0f6 | 676 | char *strsep(char **s, const char *ct) |
1da177e4 | 677 | { |
51a0f0f6 JJ |
678 | char *sbegin = *s; |
679 | char *end; | |
1da177e4 LT |
680 | |
681 | if (sbegin == NULL) | |
682 | return NULL; | |
683 | ||
684 | end = strpbrk(sbegin, ct); | |
685 | if (end) | |
686 | *end++ = '\0'; | |
687 | *s = end; | |
1da177e4 LT |
688 | return sbegin; |
689 | } | |
1da177e4 LT |
690 | EXPORT_SYMBOL(strsep); |
691 | #endif | |
692 | ||
34990cf7 DB |
693 | /** |
694 | * sysfs_streq - return true if strings are equal, modulo trailing newline | |
695 | * @s1: one string | |
696 | * @s2: another string | |
697 | * | |
698 | * This routine returns true iff two strings are equal, treating both | |
699 | * NUL and newline-then-NUL as equivalent string terminations. It's | |
700 | * geared for use with sysfs input strings, which generally terminate | |
701 | * with newlines but are compared against values without newlines. | |
702 | */ | |
703 | bool sysfs_streq(const char *s1, const char *s2) | |
704 | { | |
705 | while (*s1 && *s1 == *s2) { | |
706 | s1++; | |
707 | s2++; | |
708 | } | |
709 | ||
710 | if (*s1 == *s2) | |
711 | return true; | |
712 | if (!*s1 && *s2 == '\n' && !s2[1]) | |
713 | return true; | |
714 | if (*s1 == '\n' && !s1[1] && !*s2) | |
715 | return true; | |
716 | return false; | |
717 | } | |
718 | EXPORT_SYMBOL(sysfs_streq); | |
719 | ||
56b06081 AS |
720 | /** |
721 | * match_string - matches given string in an array | |
722 | * @array: array of strings | |
723 | * @n: number of strings in the array or -1 for NULL terminated arrays | |
724 | * @string: string to match with | |
725 | * | |
c11d3fa0 AA |
726 | * This routine will look for a string in an array of strings up to the |
727 | * n-th element in the array or until the first NULL element. | |
728 | * | |
729 | * Historically the value of -1 for @n, was used to search in arrays that | |
730 | * are NULL terminated. However, the function does not make a distinction | |
731 | * when finishing the search: either @n elements have been compared OR | |
732 | * the first NULL element was found. | |
733 | * | |
56b06081 AS |
734 | * Return: |
735 | * index of a @string in the @array if matches, or %-EINVAL otherwise. | |
736 | */ | |
737 | int match_string(const char * const *array, size_t n, const char *string) | |
738 | { | |
739 | int index; | |
740 | const char *item; | |
741 | ||
742 | for (index = 0; index < n; index++) { | |
743 | item = array[index]; | |
744 | if (!item) | |
745 | break; | |
746 | if (!strcmp(item, string)) | |
747 | return index; | |
748 | } | |
749 | ||
750 | return -EINVAL; | |
751 | } | |
752 | EXPORT_SYMBOL(match_string); | |
753 | ||
e1fe7b6a HK |
754 | /** |
755 | * __sysfs_match_string - matches given string in an array | |
756 | * @array: array of strings | |
757 | * @n: number of strings in the array or -1 for NULL terminated arrays | |
758 | * @str: string to match with | |
759 | * | |
760 | * Returns index of @str in the @array or -EINVAL, just like match_string(). | |
761 | * Uses sysfs_streq instead of strcmp for matching. | |
c11d3fa0 AA |
762 | * |
763 | * This routine will look for a string in an array of strings up to the | |
764 | * n-th element in the array or until the first NULL element. | |
765 | * | |
766 | * Historically the value of -1 for @n, was used to search in arrays that | |
767 | * are NULL terminated. However, the function does not make a distinction | |
768 | * when finishing the search: either @n elements have been compared OR | |
769 | * the first NULL element was found. | |
e1fe7b6a HK |
770 | */ |
771 | int __sysfs_match_string(const char * const *array, size_t n, const char *str) | |
772 | { | |
773 | const char *item; | |
774 | int index; | |
775 | ||
776 | for (index = 0; index < n; index++) { | |
777 | item = array[index]; | |
778 | if (!item) | |
779 | break; | |
780 | if (sysfs_streq(item, str)) | |
781 | return index; | |
782 | } | |
783 | ||
784 | return -EINVAL; | |
785 | } | |
786 | EXPORT_SYMBOL(__sysfs_match_string); | |
787 | ||
1da177e4 LT |
788 | #ifndef __HAVE_ARCH_MEMSET |
789 | /** | |
790 | * memset - Fill a region of memory with the given value | |
791 | * @s: Pointer to the start of the area. | |
792 | * @c: The byte to fill the area with | |
793 | * @count: The size of the area. | |
794 | * | |
795 | * Do not use memset() to access IO space, use memset_io() instead. | |
796 | */ | |
51a0f0f6 | 797 | void *memset(void *s, int c, size_t count) |
1da177e4 | 798 | { |
850b9247 | 799 | char *xs = s; |
1da177e4 LT |
800 | |
801 | while (count--) | |
802 | *xs++ = c; | |
1da177e4 LT |
803 | return s; |
804 | } | |
805 | EXPORT_SYMBOL(memset); | |
806 | #endif | |
807 | ||
3b3c4bab MW |
808 | #ifndef __HAVE_ARCH_MEMSET16 |
809 | /** | |
810 | * memset16() - Fill a memory area with a uint16_t | |
811 | * @s: Pointer to the start of the area. | |
812 | * @v: The value to fill the area with | |
813 | * @count: The number of values to store | |
814 | * | |
815 | * Differs from memset() in that it fills with a uint16_t instead | |
816 | * of a byte. Remember that @count is the number of uint16_ts to | |
817 | * store, not the number of bytes. | |
818 | */ | |
819 | void *memset16(uint16_t *s, uint16_t v, size_t count) | |
820 | { | |
821 | uint16_t *xs = s; | |
822 | ||
823 | while (count--) | |
824 | *xs++ = v; | |
825 | return s; | |
826 | } | |
827 | EXPORT_SYMBOL(memset16); | |
828 | #endif | |
829 | ||
830 | #ifndef __HAVE_ARCH_MEMSET32 | |
831 | /** | |
832 | * memset32() - Fill a memory area with a uint32_t | |
833 | * @s: Pointer to the start of the area. | |
834 | * @v: The value to fill the area with | |
835 | * @count: The number of values to store | |
836 | * | |
837 | * Differs from memset() in that it fills with a uint32_t instead | |
838 | * of a byte. Remember that @count is the number of uint32_ts to | |
839 | * store, not the number of bytes. | |
840 | */ | |
841 | void *memset32(uint32_t *s, uint32_t v, size_t count) | |
842 | { | |
843 | uint32_t *xs = s; | |
844 | ||
845 | while (count--) | |
846 | *xs++ = v; | |
847 | return s; | |
848 | } | |
849 | EXPORT_SYMBOL(memset32); | |
850 | #endif | |
851 | ||
852 | #ifndef __HAVE_ARCH_MEMSET64 | |
853 | /** | |
854 | * memset64() - Fill a memory area with a uint64_t | |
855 | * @s: Pointer to the start of the area. | |
856 | * @v: The value to fill the area with | |
857 | * @count: The number of values to store | |
858 | * | |
859 | * Differs from memset() in that it fills with a uint64_t instead | |
860 | * of a byte. Remember that @count is the number of uint64_ts to | |
861 | * store, not the number of bytes. | |
862 | */ | |
863 | void *memset64(uint64_t *s, uint64_t v, size_t count) | |
864 | { | |
865 | uint64_t *xs = s; | |
866 | ||
867 | while (count--) | |
868 | *xs++ = v; | |
869 | return s; | |
870 | } | |
871 | EXPORT_SYMBOL(memset64); | |
872 | #endif | |
873 | ||
1da177e4 LT |
874 | #ifndef __HAVE_ARCH_MEMCPY |
875 | /** | |
876 | * memcpy - Copy one area of memory to another | |
877 | * @dest: Where to copy to | |
878 | * @src: Where to copy from | |
879 | * @count: The size of the area. | |
880 | * | |
881 | * You should not use this function to access IO space, use memcpy_toio() | |
882 | * or memcpy_fromio() instead. | |
883 | */ | |
51a0f0f6 | 884 | void *memcpy(void *dest, const void *src, size_t count) |
1da177e4 | 885 | { |
850b9247 | 886 | char *tmp = dest; |
4c416ab7 | 887 | const char *s = src; |
1da177e4 LT |
888 | |
889 | while (count--) | |
890 | *tmp++ = *s++; | |
1da177e4 LT |
891 | return dest; |
892 | } | |
893 | EXPORT_SYMBOL(memcpy); | |
894 | #endif | |
895 | ||
896 | #ifndef __HAVE_ARCH_MEMMOVE | |
897 | /** | |
898 | * memmove - Copy one area of memory to another | |
899 | * @dest: Where to copy to | |
900 | * @src: Where to copy from | |
901 | * @count: The size of the area. | |
902 | * | |
903 | * Unlike memcpy(), memmove() copes with overlapping areas. | |
904 | */ | |
51a0f0f6 | 905 | void *memmove(void *dest, const void *src, size_t count) |
1da177e4 | 906 | { |
82da2c37 PJ |
907 | char *tmp; |
908 | const char *s; | |
1da177e4 LT |
909 | |
910 | if (dest <= src) { | |
850b9247 JJ |
911 | tmp = dest; |
912 | s = src; | |
1da177e4 LT |
913 | while (count--) |
914 | *tmp++ = *s++; | |
51a0f0f6 | 915 | } else { |
850b9247 JJ |
916 | tmp = dest; |
917 | tmp += count; | |
918 | s = src; | |
919 | s += count; | |
1da177e4 LT |
920 | while (count--) |
921 | *--tmp = *--s; | |
51a0f0f6 | 922 | } |
1da177e4 LT |
923 | return dest; |
924 | } | |
925 | EXPORT_SYMBOL(memmove); | |
926 | #endif | |
927 | ||
928 | #ifndef __HAVE_ARCH_MEMCMP | |
929 | /** | |
930 | * memcmp - Compare two areas of memory | |
931 | * @cs: One area of memory | |
932 | * @ct: Another area of memory | |
933 | * @count: The size of the area. | |
934 | */ | |
0c28130b | 935 | #undef memcmp |
a7330c99 | 936 | __visible int memcmp(const void *cs, const void *ct, size_t count) |
1da177e4 LT |
937 | { |
938 | const unsigned char *su1, *su2; | |
939 | int res = 0; | |
940 | ||
51a0f0f6 | 941 | for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--) |
1da177e4 LT |
942 | if ((res = *su1 - *su2) != 0) |
943 | break; | |
944 | return res; | |
945 | } | |
946 | EXPORT_SYMBOL(memcmp); | |
947 | #endif | |
948 | ||
5f074f3e ND |
949 | #ifndef __HAVE_ARCH_BCMP |
950 | /** | |
951 | * bcmp - returns 0 if and only if the buffers have identical contents. | |
952 | * @a: pointer to first buffer. | |
953 | * @b: pointer to second buffer. | |
954 | * @len: size of buffers. | |
955 | * | |
956 | * The sign or magnitude of a non-zero return value has no particular | |
957 | * meaning, and architectures may implement their own more efficient bcmp(). So | |
958 | * while this particular implementation is a simple (tail) call to memcmp, do | |
959 | * not rely on anything but whether the return value is zero or non-zero. | |
960 | */ | |
961 | #undef bcmp | |
962 | int bcmp(const void *a, const void *b, size_t len) | |
963 | { | |
964 | return memcmp(a, b, len); | |
965 | } | |
966 | EXPORT_SYMBOL(bcmp); | |
967 | #endif | |
968 | ||
1da177e4 LT |
969 | #ifndef __HAVE_ARCH_MEMSCAN |
970 | /** | |
971 | * memscan - Find a character in an area of memory. | |
972 | * @addr: The memory area | |
973 | * @c: The byte to search for | |
974 | * @size: The size of the area. | |
975 | * | |
976 | * returns the address of the first occurrence of @c, or 1 byte past | |
977 | * the area if @c is not found | |
978 | */ | |
51a0f0f6 | 979 | void *memscan(void *addr, int c, size_t size) |
1da177e4 | 980 | { |
850b9247 | 981 | unsigned char *p = addr; |
1da177e4 LT |
982 | |
983 | while (size) { | |
984 | if (*p == c) | |
51a0f0f6 | 985 | return (void *)p; |
1da177e4 LT |
986 | p++; |
987 | size--; | |
988 | } | |
51a0f0f6 | 989 | return (void *)p; |
1da177e4 LT |
990 | } |
991 | EXPORT_SYMBOL(memscan); | |
992 | #endif | |
993 | ||
994 | #ifndef __HAVE_ARCH_STRSTR | |
995 | /** | |
996 | * strstr - Find the first substring in a %NUL terminated string | |
997 | * @s1: The string to be searched | |
998 | * @s2: The string to search for | |
999 | */ | |
51a0f0f6 | 1000 | char *strstr(const char *s1, const char *s2) |
1da177e4 | 1001 | { |
d5f1fb53 | 1002 | size_t l1, l2; |
1da177e4 LT |
1003 | |
1004 | l2 = strlen(s2); | |
1005 | if (!l2) | |
51a0f0f6 | 1006 | return (char *)s1; |
1da177e4 LT |
1007 | l1 = strlen(s1); |
1008 | while (l1 >= l2) { | |
1009 | l1--; | |
51a0f0f6 JJ |
1010 | if (!memcmp(s1, s2, l2)) |
1011 | return (char *)s1; | |
1da177e4 LT |
1012 | s1++; |
1013 | } | |
1014 | return NULL; | |
1015 | } | |
1016 | EXPORT_SYMBOL(strstr); | |
1017 | #endif | |
1018 | ||
d5f1fb53 LZ |
1019 | #ifndef __HAVE_ARCH_STRNSTR |
1020 | /** | |
1021 | * strnstr - Find the first substring in a length-limited string | |
1022 | * @s1: The string to be searched | |
1023 | * @s2: The string to search for | |
1024 | * @len: the maximum number of characters to search | |
1025 | */ | |
1026 | char *strnstr(const char *s1, const char *s2, size_t len) | |
1027 | { | |
d6a2eedf | 1028 | size_t l2; |
d5f1fb53 LZ |
1029 | |
1030 | l2 = strlen(s2); | |
1031 | if (!l2) | |
1032 | return (char *)s1; | |
d6a2eedf AGR |
1033 | while (len >= l2) { |
1034 | len--; | |
d5f1fb53 LZ |
1035 | if (!memcmp(s1, s2, l2)) |
1036 | return (char *)s1; | |
1037 | s1++; | |
1038 | } | |
1039 | return NULL; | |
1040 | } | |
1041 | EXPORT_SYMBOL(strnstr); | |
1042 | #endif | |
1043 | ||
1da177e4 LT |
1044 | #ifndef __HAVE_ARCH_MEMCHR |
1045 | /** | |
1046 | * memchr - Find a character in an area of memory. | |
1047 | * @s: The memory area | |
1048 | * @c: The byte to search for | |
1049 | * @n: The size of the area. | |
1050 | * | |
1051 | * returns the address of the first occurrence of @c, or %NULL | |
1052 | * if @c is not found | |
1053 | */ | |
1054 | void *memchr(const void *s, int c, size_t n) | |
1055 | { | |
1056 | const unsigned char *p = s; | |
1057 | while (n-- != 0) { | |
1058 | if ((unsigned char)c == *p++) { | |
51a0f0f6 | 1059 | return (void *)(p - 1); |
1da177e4 LT |
1060 | } |
1061 | } | |
1062 | return NULL; | |
1063 | } | |
1064 | EXPORT_SYMBOL(memchr); | |
1065 | #endif | |
79824820 AM |
1066 | |
1067 | static void *check_bytes8(const u8 *start, u8 value, unsigned int bytes) | |
1068 | { | |
1069 | while (bytes) { | |
1070 | if (*start != value) | |
1071 | return (void *)start; | |
1072 | start++; | |
1073 | bytes--; | |
1074 | } | |
1075 | return NULL; | |
1076 | } | |
1077 | ||
1078 | /** | |
1079 | * memchr_inv - Find an unmatching character in an area of memory. | |
1080 | * @start: The memory area | |
1081 | * @c: Find a character other than c | |
1082 | * @bytes: The size of the area. | |
1083 | * | |
1084 | * returns the address of the first character other than @c, or %NULL | |
1085 | * if the whole buffer contains just @c. | |
1086 | */ | |
1087 | void *memchr_inv(const void *start, int c, size_t bytes) | |
1088 | { | |
1089 | u8 value = c; | |
1090 | u64 value64; | |
1091 | unsigned int words, prefix; | |
1092 | ||
1093 | if (bytes <= 16) | |
1094 | return check_bytes8(start, value, bytes); | |
1095 | ||
f43804bf | 1096 | value64 = value; |
72d93104 | 1097 | #if defined(CONFIG_ARCH_HAS_FAST_MULTIPLIER) && BITS_PER_LONG == 64 |
3368e8fb | 1098 | value64 *= 0x0101010101010101ULL; |
72d93104 | 1099 | #elif defined(CONFIG_ARCH_HAS_FAST_MULTIPLIER) |
f43804bf AM |
1100 | value64 *= 0x01010101; |
1101 | value64 |= value64 << 32; | |
1102 | #else | |
1103 | value64 |= value64 << 8; | |
1104 | value64 |= value64 << 16; | |
1105 | value64 |= value64 << 32; | |
1106 | #endif | |
79824820 | 1107 | |
f43804bf | 1108 | prefix = (unsigned long)start % 8; |
79824820 | 1109 | if (prefix) { |
f43804bf AM |
1110 | u8 *r; |
1111 | ||
1112 | prefix = 8 - prefix; | |
1113 | r = check_bytes8(start, value, prefix); | |
79824820 AM |
1114 | if (r) |
1115 | return r; | |
1116 | start += prefix; | |
1117 | bytes -= prefix; | |
1118 | } | |
1119 | ||
1120 | words = bytes / 8; | |
1121 | ||
1122 | while (words) { | |
1123 | if (*(u64 *)start != value64) | |
1124 | return check_bytes8(start, value, 8); | |
1125 | start += 8; | |
1126 | words--; | |
1127 | } | |
1128 | ||
1129 | return check_bytes8(start, value, bytes % 8); | |
1130 | } | |
1131 | EXPORT_SYMBOL(memchr_inv); | |
94df2904 RV |
1132 | |
1133 | /** | |
1134 | * strreplace - Replace all occurrences of character in string. | |
1135 | * @s: The string to operate on. | |
1136 | * @old: The character being replaced. | |
1137 | * @new: The character @old is replaced with. | |
1138 | * | |
1139 | * Returns pointer to the nul byte at the end of @s. | |
1140 | */ | |
1141 | char *strreplace(char *s, char old, char new) | |
1142 | { | |
1143 | for (; *s; ++s) | |
1144 | if (*s == old) | |
1145 | *s = new; | |
1146 | return s; | |
1147 | } | |
1148 | EXPORT_SYMBOL(strreplace); | |
6974f0c4 DM |
1149 | |
1150 | void fortify_panic(const char *name) | |
1151 | { | |
1152 | pr_emerg("detected buffer overflow in %s\n", name); | |
1153 | BUG(); | |
1154 | } | |
1155 | EXPORT_SYMBOL(fortify_panic); |