1 /* Copyright (C) 1991-2015 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <http://www.gnu.org/licenses/>. */
19 * ISO C99 Standard: 7.21 String handling <string.h>
29 /* Get size_t and NULL from <stddef.h>. */
34 /* Provide correct C++ prototypes, and indicate this to the caller. This
35 requires a compatible C++ standard library. As a heuristic, we provide
36 these when the compiler indicates full conformance with C++98 or later,
37 and for older GCC versions that are known to provide a compatible
39 #if defined __cplusplus && (__cplusplus >= 199711L || __GNUC_PREREQ (4, 4))
40 # define __CORRECT_ISO_CPP_STRING_H_PROTO
45 /* Copy N bytes of SRC to DEST. */
46 extern void *memcpy (void *__restrict __dest
, const void *__restrict __src
,
47 size_t __n
) __THROW
__nonnull ((1, 2));
48 /* Copy N bytes of SRC to DEST, guaranteeing
49 correct behavior for overlapping strings. */
50 extern void *memmove (void *__dest
, const void *__src
, size_t __n
)
51 __THROW
__nonnull ((1, 2));
54 /* Copy no more than N bytes of SRC to DEST, stopping when C is found.
55 Return the position in DEST one byte past where C was copied,
56 or NULL if C was not found in the first N bytes of SRC. */
57 #if defined __USE_MISC || defined __USE_XOPEN
58 extern void *memccpy (void *__restrict __dest
, const void *__restrict __src
,
60 __THROW
__nonnull ((1, 2));
61 #endif /* Misc || X/Open. */
65 /* Set N bytes of S to C. */
66 extern void *memset (void *__s
, int __c
, size_t __n
) __THROW
__nonnull ((1));
68 /* Compare N bytes of S1 and S2. */
69 extern int memcmp (const void *__s1
, const void *__s2
, size_t __n
)
70 __THROW __attribute_pure__
__nonnull ((1, 2));
72 /* Search N bytes of S for C. */
73 #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
76 extern void *memchr (void *__s
, int __c
, size_t __n
)
77 __THROW
__asm ("memchr") __attribute_pure__
__nonnull ((1));
78 extern const void *memchr (const void *__s
, int __c
, size_t __n
)
79 __THROW
__asm ("memchr") __attribute_pure__
__nonnull ((1));
82 __extern_always_inline
void *
83 memchr (void *__s
, int __c
, size_t __n
) __THROW
85 return __builtin_memchr (__s
, __c
, __n
);
88 __extern_always_inline
const void *
89 memchr (const void *__s
, int __c
, size_t __n
) __THROW
91 return __builtin_memchr (__s
, __c
, __n
);
96 extern void *memchr (const void *__s
, int __c
, size_t __n
)
97 __THROW __attribute_pure__
__nonnull ((1));
102 /* Search in S for C. This is similar to `memchr' but there is no
104 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
105 extern "C++" void *rawmemchr (void *__s
, int __c
)
106 __THROW
__asm ("rawmemchr") __attribute_pure__
__nonnull ((1));
107 extern "C++" const void *rawmemchr (const void *__s
, int __c
)
108 __THROW
__asm ("rawmemchr") __attribute_pure__
__nonnull ((1));
110 extern void *rawmemchr (const void *__s
, int __c
)
111 __THROW __attribute_pure__
__nonnull ((1));
114 /* Search N bytes of S for the final occurrence of C. */
115 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
116 extern "C++" void *memrchr (void *__s
, int __c
, size_t __n
)
117 __THROW
__asm ("memrchr") __attribute_pure__
__nonnull ((1));
118 extern "C++" const void *memrchr (const void *__s
, int __c
, size_t __n
)
119 __THROW
__asm ("memrchr") __attribute_pure__
__nonnull ((1));
121 extern void *memrchr (const void *__s
, int __c
, size_t __n
)
122 __THROW __attribute_pure__
__nonnull ((1));
127 __BEGIN_NAMESPACE_STD
128 /* Copy SRC to DEST. */
129 extern char *strcpy (char *__restrict __dest
, const char *__restrict __src
)
130 __THROW
__nonnull ((1, 2));
131 /* Copy no more than N characters of SRC to DEST. */
132 extern char *strncpy (char *__restrict __dest
,
133 const char *__restrict __src
, size_t __n
)
134 __THROW
__nonnull ((1, 2));
136 /* Append SRC onto DEST. */
137 extern char *strcat (char *__restrict __dest
, const char *__restrict __src
)
138 __THROW
__nonnull ((1, 2));
139 /* Append no more than N characters from SRC onto DEST. */
140 extern char *strncat (char *__restrict __dest
, const char *__restrict __src
,
141 size_t __n
) __THROW
__nonnull ((1, 2));
143 /* Compare S1 and S2. */
144 extern int strcmp (const char *__s1
, const char *__s2
)
145 __THROW __attribute_pure__
__nonnull ((1, 2));
146 /* Compare N characters of S1 and S2. */
147 extern int strncmp (const char *__s1
, const char *__s2
, size_t __n
)
148 __THROW __attribute_pure__
__nonnull ((1, 2));
150 /* Compare the collated forms of S1 and S2. */
151 extern int strcoll (const char *__s1
, const char *__s2
)
152 __THROW __attribute_pure__
__nonnull ((1, 2));
153 /* Put a transformation of SRC into no more than N bytes of DEST. */
154 extern size_t strxfrm (char *__restrict __dest
,
155 const char *__restrict __src
, size_t __n
)
156 __THROW
__nonnull ((2));
159 #ifdef __USE_XOPEN2K8
160 /* The following functions are equivalent to the both above but they
161 take the locale they use for the collation as an extra argument.
162 This is not standardsized but something like will come. */
163 # include <xlocale.h>
165 /* Compare the collated forms of S1 and S2 using rules from L. */
166 extern int strcoll_l (const char *__s1
, const char *__s2
, __locale_t __l
)
167 __THROW __attribute_pure__
__nonnull ((1, 2, 3));
168 /* Put a transformation of SRC into no more than N bytes of DEST. */
169 extern size_t strxfrm_l (char *__dest
, const char *__src
, size_t __n
,
170 __locale_t __l
) __THROW
__nonnull ((2, 4));
173 #if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
174 /* Duplicate S, returning an identical malloc'd string. */
175 extern char *strdup (const char *__s
)
176 __THROW __attribute_malloc__
__nonnull ((1));
179 /* Return a malloc'd copy of at most N bytes of STRING. The
180 resultant string is terminated even if no null terminator
181 appears before STRING[N]. */
182 #if defined __USE_XOPEN2K8
183 extern char *strndup (const char *__string
, size_t __n
)
184 __THROW __attribute_malloc__
__nonnull ((1));
187 #if defined __USE_GNU && defined __GNUC__
188 /* Duplicate S, returning an identical alloca'd string. */
189 # define strdupa(s) \
192 const char *__old = (s); \
193 size_t __len = strlen (__old) + 1; \
194 char *__new = (char *) __builtin_alloca (__len); \
195 (char *) memcpy (__new, __old, __len); \
198 /* Return an alloca'd copy of at most N bytes of string. */
199 # define strndupa(s, n) \
202 const char *__old = (s); \
203 size_t __len = strnlen (__old, (n)); \
204 char *__new = (char *) __builtin_alloca (__len + 1); \
205 __new[__len] = '\0'; \
206 (char *) memcpy (__new, __old, __len); \
210 __BEGIN_NAMESPACE_STD
211 /* Find the first occurrence of C in S. */
212 #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
215 extern char *strchr (char *__s
, int __c
)
216 __THROW
__asm ("strchr") __attribute_pure__
__nonnull ((1));
217 extern const char *strchr (const char *__s
, int __c
)
218 __THROW
__asm ("strchr") __attribute_pure__
__nonnull ((1));
221 __extern_always_inline
char *
222 strchr (char *__s
, int __c
) __THROW
224 return __builtin_strchr (__s
, __c
);
227 __extern_always_inline
const char *
228 strchr (const char *__s
, int __c
) __THROW
230 return __builtin_strchr (__s
, __c
);
235 extern char *strchr (const char *__s
, int __c
)
236 __THROW __attribute_pure__
__nonnull ((1));
238 /* Find the last occurrence of C in S. */
239 #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
242 extern char *strrchr (char *__s
, int __c
)
243 __THROW
__asm ("strrchr") __attribute_pure__
__nonnull ((1));
244 extern const char *strrchr (const char *__s
, int __c
)
245 __THROW
__asm ("strrchr") __attribute_pure__
__nonnull ((1));
248 __extern_always_inline
char *
249 strrchr (char *__s
, int __c
) __THROW
251 return __builtin_strrchr (__s
, __c
);
254 __extern_always_inline
const char *
255 strrchr (const char *__s
, int __c
) __THROW
257 return __builtin_strrchr (__s
, __c
);
262 extern char *strrchr (const char *__s
, int __c
)
263 __THROW __attribute_pure__
__nonnull ((1));
268 /* This function is similar to `strchr'. But it returns a pointer to
269 the closing NUL byte in case C is not found in S. */
270 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
271 extern "C++" char *strchrnul (char *__s
, int __c
)
272 __THROW
__asm ("strchrnul") __attribute_pure__
__nonnull ((1));
273 extern "C++" const char *strchrnul (const char *__s
, int __c
)
274 __THROW
__asm ("strchrnul") __attribute_pure__
__nonnull ((1));
276 extern char *strchrnul (const char *__s
, int __c
)
277 __THROW __attribute_pure__
__nonnull ((1));
281 __BEGIN_NAMESPACE_STD
282 /* Return the length of the initial segment of S which
283 consists entirely of characters not in REJECT. */
284 extern size_t strcspn (const char *__s
, const char *__reject
)
285 __THROW __attribute_pure__
__nonnull ((1, 2));
286 /* Return the length of the initial segment of S which
287 consists entirely of characters in ACCEPT. */
288 extern size_t strspn (const char *__s
, const char *__accept
)
289 __THROW __attribute_pure__
__nonnull ((1, 2));
290 /* Find the first occurrence in S of any character in ACCEPT. */
291 #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
294 extern char *strpbrk (char *__s
, const char *__accept
)
295 __THROW
__asm ("strpbrk") __attribute_pure__
__nonnull ((1, 2));
296 extern const char *strpbrk (const char *__s
, const char *__accept
)
297 __THROW
__asm ("strpbrk") __attribute_pure__
__nonnull ((1, 2));
300 __extern_always_inline
char *
301 strpbrk (char *__s
, const char *__accept
) __THROW
303 return __builtin_strpbrk (__s
, __accept
);
306 __extern_always_inline
const char *
307 strpbrk (const char *__s
, const char *__accept
) __THROW
309 return __builtin_strpbrk (__s
, __accept
);
314 extern char *strpbrk (const char *__s
, const char *__accept
)
315 __THROW __attribute_pure__
__nonnull ((1, 2));
317 /* Find the first occurrence of NEEDLE in HAYSTACK. */
318 #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
321 extern char *strstr (char *__haystack
, const char *__needle
)
322 __THROW
__asm ("strstr") __attribute_pure__
__nonnull ((1, 2));
323 extern const char *strstr (const char *__haystack
, const char *__needle
)
324 __THROW
__asm ("strstr") __attribute_pure__
__nonnull ((1, 2));
327 __extern_always_inline
char *
328 strstr (char *__haystack
, const char *__needle
) __THROW
330 return __builtin_strstr (__haystack
, __needle
);
333 __extern_always_inline
const char *
334 strstr (const char *__haystack
, const char *__needle
) __THROW
336 return __builtin_strstr (__haystack
, __needle
);
341 extern char *strstr (const char *__haystack
, const char *__needle
)
342 __THROW __attribute_pure__
__nonnull ((1, 2));
346 /* Divide S into tokens separated by characters in DELIM. */
347 extern char *strtok (char *__restrict __s
, const char *__restrict __delim
)
348 __THROW
__nonnull ((2));
351 /* Divide S into tokens separated by characters in DELIM. Information
352 passed between calls are stored in SAVE_PTR. */
353 extern char *__strtok_r (char *__restrict __s
,
354 const char *__restrict __delim
,
355 char **__restrict __save_ptr
)
356 __THROW
__nonnull ((2, 3));
358 extern char *strtok_r (char *__restrict __s
, const char *__restrict __delim
,
359 char **__restrict __save_ptr
)
360 __THROW
__nonnull ((2, 3));
364 /* Similar to `strstr' but this function ignores the case of both strings. */
365 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
366 extern "C++" char *strcasestr (char *__haystack
, const char *__needle
)
367 __THROW
__asm ("strcasestr") __attribute_pure__
__nonnull ((1, 2));
368 extern "C++" const char *strcasestr (const char *__haystack
,
369 const char *__needle
)
370 __THROW
__asm ("strcasestr") __attribute_pure__
__nonnull ((1, 2));
372 extern char *strcasestr (const char *__haystack
, const char *__needle
)
373 __THROW __attribute_pure__
__nonnull ((1, 2));
378 /* Find the first occurrence of NEEDLE in HAYSTACK.
379 NEEDLE is NEEDLELEN bytes long;
380 HAYSTACK is HAYSTACKLEN bytes long. */
381 extern void *memmem (const void *__haystack
, size_t __haystacklen
,
382 const void *__needle
, size_t __needlelen
)
383 __THROW __attribute_pure__
__nonnull ((1, 3));
385 /* Copy N bytes of SRC to DEST, return pointer to bytes after the
386 last written byte. */
387 extern void *__mempcpy (void *__restrict __dest
,
388 const void *__restrict __src
, size_t __n
)
389 __THROW
__nonnull ((1, 2));
390 extern void *mempcpy (void *__restrict __dest
,
391 const void *__restrict __src
, size_t __n
)
392 __THROW
__nonnull ((1, 2));
396 __BEGIN_NAMESPACE_STD
397 /* Return the length of S. */
398 extern size_t strlen (const char *__s
)
399 __THROW __attribute_pure__
__nonnull ((1));
402 #ifdef __USE_XOPEN2K8
403 /* Find the length of STRING, but scan at most MAXLEN characters.
404 If no '\0' terminator is found in that many characters, return MAXLEN. */
405 extern size_t strnlen (const char *__string
, size_t __maxlen
)
406 __THROW __attribute_pure__
__nonnull ((1));
410 __BEGIN_NAMESPACE_STD
411 /* Return a string describing the meaning of the `errno' code in ERRNUM. */
412 extern char *strerror (int __errnum
) __THROW
;
415 /* Reentrant version of `strerror'.
416 There are 2 flavors of `strerror_r', GNU which returns the string
417 and may or may not use the supplied temporary buffer and POSIX one
418 which fills the string into the buffer.
419 To use the POSIX version, -D_XOPEN_SOURCE=600 or -D_POSIX_C_SOURCE=200112L
420 without -D_GNU_SOURCE is needed, otherwise the GNU version is
422 # if defined __USE_XOPEN2K && !defined __USE_GNU
423 /* Fill BUF with a string describing the meaning of the `errno' code in
425 # ifdef __REDIRECT_NTH
426 extern int __REDIRECT_NTH (strerror_r
,
427 (int __errnum
, char *__buf
, size_t __buflen
),
428 __xpg_strerror_r
) __nonnull ((2));
430 extern int __xpg_strerror_r (int __errnum
, char *__buf
, size_t __buflen
)
431 __THROW
__nonnull ((2));
432 # define strerror_r __xpg_strerror_r
435 /* If a temporary buffer is required, at most BUFLEN bytes of BUF will be
437 extern char *strerror_r (int __errnum
, char *__buf
, size_t __buflen
)
438 __THROW
__nonnull ((2)) __wur
;
442 #ifdef __USE_XOPEN2K8
443 /* Translate error number to string according to the locale L. */
444 extern char *strerror_l (int __errnum
, __locale_t __l
) __THROW
;
448 /* We define this function always since `bzero' is sometimes needed when
449 the namespace rules does not allow this. */
450 extern void __bzero (void *__s
, size_t __n
) __THROW
__nonnull ((1));
453 /* Copy N bytes of SRC to DEST (like memmove, but args reversed). */
454 extern void bcopy (const void *__src
, void *__dest
, size_t __n
)
455 __THROW
__nonnull ((1, 2));
457 /* Set N bytes of S to 0. */
458 extern void bzero (void *__s
, size_t __n
) __THROW
__nonnull ((1));
460 /* Compare N bytes of S1 and S2 (same as memcmp). */
461 extern int bcmp (const void *__s1
, const void *__s2
, size_t __n
)
462 __THROW __attribute_pure__
__nonnull ((1, 2));
464 /* Find the first occurrence of C in S (same as strchr). */
465 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
468 extern char *index (char *__s
, int __c
)
469 __THROW
__asm ("index") __attribute_pure__
__nonnull ((1));
470 extern const char *index (const char *__s
, int __c
)
471 __THROW
__asm ("index") __attribute_pure__
__nonnull ((1));
473 # if defined __OPTIMIZE__ && !defined __CORRECT_ISO_CPP_STRINGS_H_PROTO
474 __extern_always_inline
char *
475 index (char *__s
, int __c
) __THROW
477 return __builtin_index (__s
, __c
);
480 __extern_always_inline
const char *
481 index (const char *__s
, int __c
) __THROW
483 return __builtin_index (__s
, __c
);
488 extern char *index (const char *__s
, int __c
)
489 __THROW __attribute_pure__
__nonnull ((1));
492 /* Find the last occurrence of C in S (same as strrchr). */
493 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
496 extern char *rindex (char *__s
, int __c
)
497 __THROW
__asm ("rindex") __attribute_pure__
__nonnull ((1));
498 extern const char *rindex (const char *__s
, int __c
)
499 __THROW
__asm ("rindex") __attribute_pure__
__nonnull ((1));
501 # if defined __OPTIMIZE__ && !defined __CORRECT_ISO_CPP_STRINGS_H_PROTO
502 __extern_always_inline
char *
503 rindex (char *__s
, int __c
) __THROW
505 return __builtin_rindex (__s
, __c
);
508 __extern_always_inline
const char *
509 rindex (const char *__s
, int __c
) __THROW
511 return __builtin_rindex (__s
, __c
);
516 extern char *rindex (const char *__s
, int __c
)
517 __THROW __attribute_pure__
__nonnull ((1));
520 /* Return the position of the first bit set in I, or 0 if none are set.
521 The least-significant bit is position 1, the most-significant 32. */
522 extern int ffs (int __i
) __THROW
__attribute__ ((__const__
));
524 /* The following two functions are non-standard but necessary for non-32 bit
527 extern int ffsl (long int __l
) __THROW
__attribute__ ((__const__
));
528 __extension__
extern int ffsll (long long int __ll
)
529 __THROW
__attribute__ ((__const__
));
532 /* Compare S1 and S2, ignoring case. */
533 extern int strcasecmp (const char *__s1
, const char *__s2
)
534 __THROW __attribute_pure__
__nonnull ((1, 2));
536 /* Compare no more than N chars of S1 and S2, ignoring case. */
537 extern int strncasecmp (const char *__s1
, const char *__s2
, size_t __n
)
538 __THROW __attribute_pure__
__nonnull ((1, 2));
539 #endif /* Use misc. */
542 /* Again versions of a few functions which use the given locale instead
543 of the global one. */
544 extern int strcasecmp_l (const char *__s1
, const char *__s2
,
546 __THROW __attribute_pure__
__nonnull ((1, 2, 3));
548 extern int strncasecmp_l (const char *__s1
, const char *__s2
,
549 size_t __n
, __locale_t __loc
)
550 __THROW __attribute_pure__
__nonnull ((1, 2, 4));
554 /* Return the next DELIM-delimited token from *STRINGP,
555 terminating it with a '\0', and update *STRINGP to point past it. */
556 extern char *strsep (char **__restrict __stringp
,
557 const char *__restrict __delim
)
558 __THROW
__nonnull ((1, 2));
561 #ifdef __USE_XOPEN2K8
562 /* Return a string describing the meaning of the signal number in SIG. */
563 extern char *strsignal (int __sig
) __THROW
;
565 /* Copy SRC to DEST, returning the address of the terminating '\0' in DEST. */
566 extern char *__stpcpy (char *__restrict __dest
, const char *__restrict __src
)
567 __THROW
__nonnull ((1, 2));
568 extern char *stpcpy (char *__restrict __dest
, const char *__restrict __src
)
569 __THROW
__nonnull ((1, 2));
571 /* Copy no more than N characters of SRC to DEST, returning the address of
572 the last character written into DEST. */
573 extern char *__stpncpy (char *__restrict __dest
,
574 const char *__restrict __src
, size_t __n
)
575 __THROW
__nonnull ((1, 2));
576 extern char *stpncpy (char *__restrict __dest
,
577 const char *__restrict __src
, size_t __n
)
578 __THROW
__nonnull ((1, 2));
582 /* Compare S1 and S2 as strings holding name & indices/version numbers. */
583 extern int strverscmp (const char *__s1
, const char *__s2
)
584 __THROW __attribute_pure__
__nonnull ((1, 2));
586 /* Sautee STRING briskly. */
587 extern char *strfry (char *__string
) __THROW
__nonnull ((1));
589 /* Frobnicate N bytes of S. */
590 extern void *memfrob (void *__s
, size_t __n
) __THROW
__nonnull ((1));
593 /* Return the file name within directory of FILENAME. We don't
594 declare the function if the `basename' macro is available (defined
595 in <libgen.h>) which makes the XPG version of this function
597 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
598 extern "C++" char *basename (char *__filename
)
599 __THROW
__asm ("basename") __nonnull ((1));
600 extern "C++" const char *basename (const char *__filename
)
601 __THROW
__asm ("basename") __nonnull ((1));
603 extern char *basename (const char *__filename
) __THROW
__nonnull ((1));
609 #if defined __GNUC__ && __GNUC__ >= 2
610 # if defined __OPTIMIZE__ && !defined __OPTIMIZE_SIZE__ \
611 && !defined __NO_INLINE__ && !defined __cplusplus
612 /* When using GNU CC we provide some optimized versions of selected
613 functions from this header. There are two kinds of optimizations:
615 - machine-dependent optimizations, most probably using inline
616 assembler code; these might be quite expensive since the code
617 size can increase significantly.
618 These optimizations are not used unless the symbol
620 is defined before including this header.
622 - machine-independent optimizations which do not increase the
623 code size significantly and which optimize mainly situations
624 where one or more arguments are compile-time constants.
625 These optimizations are used always when the compiler is
628 One can inhibit all optimizations by defining __NO_STRING_INLINES. */
630 /* Get the machine-dependent optimizations (if any). */
631 # include <bits/string.h>
633 /* These are generic optimizations which do not add too much inline code. */
634 # include <bits/string2.h>
637 # if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
638 /* Functions with security checks. */
639 # include <bits/string3.h>
645 #endif /* string.h */