1/* 2 * linux/lib/string.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 */ 6 7/* 8 * stupid library routines.. The optimized versions should generally be found 9 * as inline code in <asm-xx/string.h> 10 * 11 * These are buggy as well.. 12 * 13 * * Fri Jun 25 1999, Ingo Oeser <ioe@informatik.tu-chemnitz.de> 14 * - Added strsep() which will replace strtok() soon (because strsep() is 15 * reentrant and should be faster). Use only strsep() in new code, please. 16 * 17 * * Sat Feb 09 2002, Jason Thomas <jason@topic.com.au>, 18 * Matthew Hawkins <matt@mh.dropbear.id.au> 19 * - Kissed strtok() goodbye 20 */ 21 22#include <linux/types.h> 23#include <linux/string.h> 24#include <linux/ctype.h> 25#include <linux/module.h> 26 27#include <typedefs.h> 28#include <bcmdefs.h> 29 30#ifndef __HAVE_ARCH_STRNICMP 31/** 32 * strnicmp - Case insensitive, length-limited string comparison 33 * @s1: One string 34 * @s2: The other string 35 * @len: the maximum number of characters to compare 36 */ 37int strnicmp(const char *s1, const char *s2, size_t len) 38{ 39 /* Yes, Virginia, it had better be unsigned */ 40 unsigned char c1, c2; 41 42 c1 = c2 = 0; 43 if (len) { 44 do { 45 c1 = *s1; 46 c2 = *s2; 47 s1++; 48 s2++; 49 if (!c1) 50 break; 51 if (!c2) 52 break; 53 if (c1 == c2) 54 continue; 55 c1 = tolower(c1); 56 c2 = tolower(c2); 57 if (c1 != c2) 58 break; 59 } while (--len); 60 } 61 return (int)c1 - (int)c2; 62} 63EXPORT_SYMBOL(strnicmp); 64#endif 65 66#ifndef __HAVE_ARCH_STRCASECMP 67int strcasecmp(const char *s1, const char *s2) 68{ 69 int c1, c2; 70 71 do { 72 c1 = tolower(*s1++); 73 c2 = tolower(*s2++); 74 } while (c1 == c2 && c1 != 0); 75 return c1 - c2; 76} 77EXPORT_SYMBOL(strcasecmp); 78#endif 79 80#ifndef __HAVE_ARCH_STRNCASECMP 81int strncasecmp(const char *s1, const char *s2, size_t n) 82{ 83 int c1, c2; 84 85 do { 86 c1 = tolower(*s1++); 87 c2 = tolower(*s2++); 88 } while ((--n > 0) && c1 == c2 && c1 != 0); 89 return c1 - c2; 90} 91EXPORT_SYMBOL(strncasecmp); 92#endif 93 94#ifndef __HAVE_ARCH_STRCPY 95/** 96 * strcpy - Copy a %NUL terminated string 97 * @dest: Where to copy the string to 98 * @src: Where to copy the string from 99 */ 100#undef strcpy 101char *strcpy(char *dest, const char *src) 102{ 103 char *tmp = dest; 104 105 while ((*dest++ = *src++) != '\0') 106 /* nothing */; 107 return tmp; 108} 109EXPORT_SYMBOL(strcpy); 110#endif 111 112#ifndef __HAVE_ARCH_STRNCPY 113/** 114 * strncpy - Copy a length-limited, %NUL-terminated string 115 * @dest: Where to copy the string to 116 * @src: Where to copy the string from 117 * @count: The maximum number of bytes to copy 118 * 119 * The result is not %NUL-terminated if the source exceeds 120 * @count bytes. 121 * 122 * In the case where the length of @src is less than that of 123 * count, the remainder of @dest will be padded with %NUL. 124 * 125 */ 126char *strncpy(char *dest, const char *src, size_t count) 127{ 128 char *tmp = dest; 129 130 while (count) { 131 if ((*tmp = *src) != 0) 132 src++; 133 tmp++; 134 count--; 135 } 136 return dest; 137} 138EXPORT_SYMBOL(strncpy); 139#endif 140 141#ifndef __HAVE_ARCH_STRLCPY 142/** 143 * strlcpy - Copy a %NUL terminated string into a sized buffer 144 * @dest: Where to copy the string to 145 * @src: Where to copy the string from 146 * @size: size of destination buffer 147 * 148 * Compatible with *BSD: the result is always a valid 149 * NUL-terminated string that fits in the buffer (unless, 150 * of course, the buffer size is zero). It does not pad 151 * out the result like strncpy() does. 152 */ 153size_t strlcpy(char *dest, const char *src, size_t size) 154{ 155 size_t ret = strlen(src); 156 157 if (size) { 158 size_t len = (ret >= size) ? size - 1 : ret; 159 memcpy(dest, src, len); 160 dest[len] = '\0'; 161 } 162 return ret; 163} 164EXPORT_SYMBOL(strlcpy); 165#endif 166 167#ifndef __HAVE_ARCH_STRCAT 168/** 169 * strcat - Append one %NUL-terminated string to another 170 * @dest: The string to be appended to 171 * @src: The string to append to it 172 */ 173#undef strcat 174char *strcat(char *dest, const char *src) 175{ 176 char *tmp = dest; 177 178 while (*dest) 179 dest++; 180 while ((*dest++ = *src++) != '\0') 181 ; 182 return tmp; 183} 184EXPORT_SYMBOL(strcat); 185#endif 186 187#ifndef __HAVE_ARCH_STRNCAT 188/** 189 * strncat - Append a length-limited, %NUL-terminated string to another 190 * @dest: The string to be appended to 191 * @src: The string to append to it 192 * @count: The maximum numbers of bytes to copy 193 * 194 * Note that in contrast to strncpy(), strncat() ensures the result is 195 * terminated. 196 */ 197char *strncat(char *dest, const char *src, size_t count) 198{ 199 char *tmp = dest; 200 201 if (count) { 202 while (*dest) 203 dest++; 204 while ((*dest++ = *src++) != 0) { 205 if (--count == 0) { 206 *dest = '\0'; 207 break; 208 } 209 } 210 } 211 return tmp; 212} 213EXPORT_SYMBOL(strncat); 214#endif 215 216#ifndef __HAVE_ARCH_STRLCAT 217/** 218 * strlcat - Append a length-limited, %NUL-terminated string to another 219 * @dest: The string to be appended to 220 * @src: The string to append to it 221 * @count: The size of the destination buffer. 222 */ 223size_t strlcat(char *dest, const char *src, size_t count) 224{ 225 size_t dsize = strlen(dest); 226 size_t len = strlen(src); 227 size_t res = dsize + len; 228 229 /* This would be a bug */ 230 BUG_ON(dsize >= count); 231 232 dest += dsize; 233 count -= dsize; 234 if (len >= count) 235 len = count-1; 236 memcpy(dest, src, len); 237 dest[len] = 0; 238 return res; 239} 240EXPORT_SYMBOL(strlcat); 241#endif 242 243#ifndef __HAVE_ARCH_STRCMP 244/** 245 * strcmp - Compare two strings 246 * @cs: One string 247 * @ct: Another string 248 */ 249#undef strcmp 250int strcmp(const char *cs, const char *ct) 251{ 252 signed char __res; 253 254 while (1) { 255 if ((__res = *cs - *ct++) != 0 || !*cs++) 256 break; 257 } 258 return __res; 259} 260EXPORT_SYMBOL(strcmp); 261#endif 262 263#ifndef __HAVE_ARCH_STRNCMP 264/** 265 * strncmp - Compare two length-limited strings 266 * @cs: One string 267 * @ct: Another string 268 * @count: The maximum number of bytes to compare 269 */ 270int strncmp(const char *cs, const char *ct, size_t count) 271{ 272 signed char __res = 0; 273 274 while (count) { 275 if ((__res = *cs - *ct++) != 0 || !*cs++) 276 break; 277 count--; 278 } 279 return __res; 280} 281EXPORT_SYMBOL(strncmp); 282#endif 283 284#ifndef __HAVE_ARCH_STRCHR 285/** 286 * strchr - Find the first occurrence of a character in a string 287 * @s: The string to be searched 288 * @c: The character to search for 289 */ 290char *strchr(const char *s, int c) 291{ 292 for (; *s != (char)c; ++s) 293 if (*s == '\0') 294 return NULL; 295 return (char *)s; 296} 297EXPORT_SYMBOL(strchr); 298#endif 299 300#ifndef __HAVE_ARCH_STRRCHR 301/** 302 * strrchr - Find the last occurrence of a character in a string 303 * @s: The string to be searched 304 * @c: The character to search for 305 */ 306char *strrchr(const char *s, int c) 307{ 308 const char *p = s + strlen(s); 309 do { 310 if (*p == (char)c) 311 return (char *)p; 312 } while (--p >= s); 313 return NULL; 314} 315EXPORT_SYMBOL(strrchr); 316#endif 317 318#ifndef __HAVE_ARCH_STRNCHR 319/** 320 * strnchr - Find a character in a length limited string 321 * @s: The string to be searched 322 * @count: The number of characters to be searched 323 * @c: The character to search for 324 */ 325char *strnchr(const char *s, size_t count, int c) 326{ 327 for (; count-- && *s != '\0'; ++s) 328 if (*s == (char)c) 329 return (char *)s; 330 return NULL; 331} 332EXPORT_SYMBOL(strnchr); 333#endif 334 335/** 336 * strstrip - Removes leading and trailing whitespace from @s. 337 * @s: The string to be stripped. 338 * 339 * Note that the first trailing whitespace is replaced with a %NUL-terminator 340 * in the given string @s. Returns a pointer to the first non-whitespace 341 * character in @s. 342 */ 343char *strstrip(char *s) 344{ 345 size_t size; 346 char *end; 347 348 size = strlen(s); 349 350 if (!size) 351 return s; 352 353 end = s + size - 1; 354 while (end >= s && isspace(*end)) 355 end--; 356 *(end + 1) = '\0'; 357 358 while (*s && isspace(*s)) 359 s++; 360 361 return s; 362} 363EXPORT_SYMBOL(strstrip); 364 365#ifndef __HAVE_ARCH_STRLEN 366/** 367 * strlen - Find the length of a string 368 * @s: The string to be sized 369 */ 370size_t strlen(const char *s) 371{ 372 const char *sc; 373 374 for (sc = s; *sc != '\0'; ++sc) 375 /* nothing */; 376 return sc - s; 377} 378EXPORT_SYMBOL(strlen); 379#endif 380 381#ifndef __HAVE_ARCH_STRNLEN 382/** 383 * strnlen - Find the length of a length-limited string 384 * @s: The string to be sized 385 * @count: The maximum number of bytes to search 386 */ 387size_t strnlen(const char *s, size_t count) 388{ 389 const char *sc; 390 391 for (sc = s; count-- && *sc != '\0'; ++sc) 392 /* nothing */; 393 return sc - s; 394} 395EXPORT_SYMBOL(strnlen); 396#endif 397 398#ifndef __HAVE_ARCH_STRSPN 399/** 400 * strspn - Calculate the length of the initial substring of @s which only contain letters in @accept 401 * @s: The string to be searched 402 * @accept: The string to search for 403 */ 404size_t strspn(const char *s, const char *accept) 405{ 406 const char *p; 407 const char *a; 408 size_t count = 0; 409 410 for (p = s; *p != '\0'; ++p) { 411 for (a = accept; *a != '\0'; ++a) { 412 if (*p == *a) 413 break; 414 } 415 if (*a == '\0') 416 return count; 417 ++count; 418 } 419 return count; 420} 421 422EXPORT_SYMBOL(strspn); 423#endif 424 425#ifndef __HAVE_ARCH_STRCSPN 426/** 427 * strcspn - Calculate the length of the initial substring of @s which does not contain letters in @reject 428 * @s: The string to be searched 429 * @reject: The string to avoid 430 */ 431size_t strcspn(const char *s, const char *reject) 432{ 433 const char *p; 434 const char *r; 435 size_t count = 0; 436 437 for (p = s; *p != '\0'; ++p) { 438 for (r = reject; *r != '\0'; ++r) { 439 if (*p == *r) 440 return count; 441 } 442 ++count; 443 } 444 return count; 445} 446EXPORT_SYMBOL(strcspn); 447#endif 448 449#ifndef __HAVE_ARCH_STRPBRK 450/** 451 * strpbrk - Find the first occurrence of a set of characters 452 * @cs: The string to be searched 453 * @ct: The characters to search for 454 */ 455char *strpbrk(const char *cs, const char *ct) 456{ 457 const char *sc1, *sc2; 458 459 for (sc1 = cs; *sc1 != '\0'; ++sc1) { 460 for (sc2 = ct; *sc2 != '\0'; ++sc2) { 461 if (*sc1 == *sc2) 462 return (char *)sc1; 463 } 464 } 465 return NULL; 466} 467EXPORT_SYMBOL(strpbrk); 468#endif 469 470#ifndef __HAVE_ARCH_STRSEP 471/** 472 * strsep - Split a string into tokens 473 * @s: The string to be searched 474 * @ct: The characters to search for 475 * 476 * strsep() updates @s to point after the token, ready for the next call. 477 * 478 * It returns empty tokens, too, behaving exactly like the libc function 479 * of that name. In fact, it was stolen from glibc2 and de-fancy-fied. 480 * Same semantics, slimmer shape. ;) 481 */ 482char *strsep(char **s, const char *ct) 483{ 484 char *sbegin = *s; 485 char *end; 486 487 if (sbegin == NULL) 488 return NULL; 489 490 end = strpbrk(sbegin, ct); 491 if (end) 492 *end++ = '\0'; 493 *s = end; 494 return sbegin; 495} 496EXPORT_SYMBOL(strsep); 497#endif 498 499#ifndef __HAVE_ARCH_MEMSET 500/** 501 * memset - Fill a region of memory with the given value 502 * @s: Pointer to the start of the area. 503 * @c: The byte to fill the area with 504 * @count: The size of the area. 505 * 506 * Do not use memset() to access IO space, use memset_io() instead. 507 */ 508void *memset(void *s, int c, size_t count) 509{ 510 char *xs = s; 511 512 while (count--) 513 *xs++ = c; 514 return s; 515} 516EXPORT_SYMBOL(memset); 517#endif 518 519#ifndef __HAVE_ARCH_MEMCPY 520/** 521 * memcpy - Copy one area of memory to another 522 * @dest: Where to copy to 523 * @src: Where to copy from 524 * @count: The size of the area. 525 * 526 * You should not use this function to access IO space, use memcpy_toio() 527 * or memcpy_fromio() instead. 528 */ 529void *memcpy(void *dest, const void *src, size_t count) 530{ 531 char *tmp = dest; 532 const char *s = src; 533 534 while (count--) 535 *tmp++ = *s++; 536 return dest; 537} 538EXPORT_SYMBOL(memcpy); 539#endif 540 541#ifndef __HAVE_ARCH_MEMMOVE 542/** 543 * memmove - Copy one area of memory to another 544 * @dest: Where to copy to 545 * @src: Where to copy from 546 * @count: The size of the area. 547 * 548 * Unlike memcpy(), memmove() copes with overlapping areas. 549 */ 550void *memmove(void *dest, const void *src, size_t count) 551{ 552 char *tmp; 553 const char *s; 554 555 if (dest <= src) { 556 tmp = dest; 557 s = src; 558 while (count--) 559 *tmp++ = *s++; 560 } else { 561 tmp = dest; 562 tmp += count; 563 s = src; 564 s += count; 565 while (count--) 566 *--tmp = *--s; 567 } 568 return dest; 569} 570EXPORT_SYMBOL(memmove); 571#endif 572 573#ifndef __HAVE_ARCH_MEMCMP 574/** 575 * memcmp - Compare two areas of memory 576 * @cs: One area of memory 577 * @ct: Another area of memory 578 * @count: The size of the area. 579 */ 580#undef memcmp 581int BCMFASTPATH memcmp(const void *cs, const void *ct, size_t count) 582{ 583 const unsigned char *su1, *su2; 584 int res = 0; 585 586 for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--) 587 if ((res = *su1 - *su2) != 0) 588 break; 589 return res; 590} 591EXPORT_SYMBOL(memcmp); 592#endif 593 594#ifndef __HAVE_ARCH_MEMSCAN 595/** 596 * memscan - Find a character in an area of memory. 597 * @addr: The memory area 598 * @c: The byte to search for 599 * @size: The size of the area. 600 * 601 * returns the address of the first occurrence of @c, or 1 byte past 602 * the area if @c is not found 603 */ 604void *memscan(void *addr, int c, size_t size) 605{ 606 unsigned char *p = addr; 607 608 while (size) { 609 if (*p == c) 610 return (void *)p; 611 p++; 612 size--; 613 } 614 return (void *)p; 615} 616EXPORT_SYMBOL(memscan); 617#endif 618 619#ifndef __HAVE_ARCH_STRSTR 620/** 621 * strstr - Find the first substring in a %NUL terminated string 622 * @s1: The string to be searched 623 * @s2: The string to search for 624 */ 625char *strstr(const char *s1, const char *s2) 626{ 627 int l1, l2; 628 629 l2 = strlen(s2); 630 if (!l2) 631 return (char *)s1; 632 l1 = strlen(s1); 633 while (l1 >= l2) { 634 l1--; 635 if (!memcmp(s1, s2, l2)) 636 return (char *)s1; 637 s1++; 638 } 639 return NULL; 640} 641EXPORT_SYMBOL(strstr); 642#endif 643 644#ifndef __HAVE_ARCH_MEMCHR 645/** 646 * memchr - Find a character in an area of memory. 647 * @s: The memory area 648 * @c: The byte to search for 649 * @n: The size of the area. 650 * 651 * returns the address of the first occurrence of @c, or %NULL 652 * if @c is not found 653 */ 654void *memchr(const void *s, int c, size_t n) 655{ 656 const unsigned char *p = s; 657 while (n-- != 0) { 658 if ((unsigned char)c == *p++) { 659 return (void *)(p - 1); 660 } 661 } 662 return NULL; 663} 664EXPORT_SYMBOL(memchr); 665#endif 666