Don't define x86-64 __strncmp_ssse3 in libc.a
[glibc.git] / string / string.h
blob879410aee0faff52436aa6be93621f06384ae73a
1 /* Copyright (C) 1991-2012 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>
22 #ifndef _STRING_H
23 #define _STRING_H 1
25 #include <features.h>
27 __BEGIN_DECLS
29 /* Get size_t and NULL from <stddef.h>. */
30 #define __need_size_t
31 #define __need_NULL
32 #include <stddef.h>
34 /* Tell the caller that we provide correct C++ prototypes. */
35 #if defined __cplusplus && __GNUC_PREREQ (4, 4)
36 # define __CORRECT_ISO_CPP_STRING_H_PROTO
37 #endif
40 __BEGIN_NAMESPACE_STD
41 /* Copy N bytes of SRC to DEST. */
42 extern void *memcpy (void *__restrict __dest, const void *__restrict __src,
43 size_t __n) __THROW __nonnull ((1, 2));
44 /* Copy N bytes of SRC to DEST, guaranteeing
45 correct behavior for overlapping strings. */
46 extern void *memmove (void *__dest, const void *__src, size_t __n)
47 __THROW __nonnull ((1, 2));
48 __END_NAMESPACE_STD
50 /* Copy no more than N bytes of SRC to DEST, stopping when C is found.
51 Return the position in DEST one byte past where C was copied,
52 or NULL if C was not found in the first N bytes of SRC. */
53 #if defined __USE_SVID || defined __USE_BSD || defined __USE_XOPEN
54 extern void *memccpy (void *__restrict __dest, const void *__restrict __src,
55 int __c, size_t __n)
56 __THROW __nonnull ((1, 2));
57 #endif /* SVID. */
60 __BEGIN_NAMESPACE_STD
61 /* Set N bytes of S to C. */
62 extern void *memset (void *__s, int __c, size_t __n) __THROW __nonnull ((1));
64 /* Compare N bytes of S1 and S2. */
65 extern int memcmp (const void *__s1, const void *__s2, size_t __n)
66 __THROW __attribute_pure__ __nonnull ((1, 2));
68 /* Search N bytes of S for C. */
69 #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
70 extern "C++"
72 extern void *memchr (void *__s, int __c, size_t __n)
73 __THROW __asm ("memchr") __attribute_pure__ __nonnull ((1));
74 extern const void *memchr (const void *__s, int __c, size_t __n)
75 __THROW __asm ("memchr") __attribute_pure__ __nonnull ((1));
77 # ifdef __OPTIMIZE__
78 __extern_always_inline void *
79 memchr (void *__s, int __c, size_t __n) __THROW
81 return __builtin_memchr (__s, __c, __n);
84 __extern_always_inline const void *
85 memchr (const void *__s, int __c, size_t __n) __THROW
87 return __builtin_memchr (__s, __c, __n);
89 # endif
91 #else
92 extern void *memchr (const void *__s, int __c, size_t __n)
93 __THROW __attribute_pure__ __nonnull ((1));
94 #endif
95 __END_NAMESPACE_STD
97 #ifdef __USE_GNU
98 /* Search in S for C. This is similar to `memchr' but there is no
99 length limit. */
100 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
101 extern "C++" void *rawmemchr (void *__s, int __c)
102 __THROW __asm ("rawmemchr") __attribute_pure__ __nonnull ((1));
103 extern "C++" const void *rawmemchr (const void *__s, int __c)
104 __THROW __asm ("rawmemchr") __attribute_pure__ __nonnull ((1));
105 # else
106 extern void *rawmemchr (const void *__s, int __c)
107 __THROW __attribute_pure__ __nonnull ((1));
108 # endif
110 /* Search N bytes of S for the final occurrence of C. */
111 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
112 extern "C++" void *memrchr (void *__s, int __c, size_t __n)
113 __THROW __asm ("memrchr") __attribute_pure__ __nonnull ((1));
114 extern "C++" const void *memrchr (const void *__s, int __c, size_t __n)
115 __THROW __asm ("memrchr") __attribute_pure__ __nonnull ((1));
116 # else
117 extern void *memrchr (const void *__s, int __c, size_t __n)
118 __THROW __attribute_pure__ __nonnull ((1));
119 # endif
120 #endif
123 __BEGIN_NAMESPACE_STD
124 /* Copy SRC to DEST. */
125 extern char *strcpy (char *__restrict __dest, const char *__restrict __src)
126 __THROW __nonnull ((1, 2));
127 /* Copy no more than N characters of SRC to DEST. */
128 extern char *strncpy (char *__restrict __dest,
129 const char *__restrict __src, size_t __n)
130 __THROW __nonnull ((1, 2));
132 /* Append SRC onto DEST. */
133 extern char *strcat (char *__restrict __dest, const char *__restrict __src)
134 __THROW __nonnull ((1, 2));
135 /* Append no more than N characters from SRC onto DEST. */
136 extern char *strncat (char *__restrict __dest, const char *__restrict __src,
137 size_t __n) __THROW __nonnull ((1, 2));
139 /* Compare S1 and S2. */
140 extern int strcmp (const char *__s1, const char *__s2)
141 __THROW __attribute_pure__ __nonnull ((1, 2));
142 /* Compare N characters of S1 and S2. */
143 extern int strncmp (const char *__s1, const char *__s2, size_t __n)
144 __THROW __attribute_pure__ __nonnull ((1, 2));
146 /* Compare the collated forms of S1 and S2. */
147 extern int strcoll (const char *__s1, const char *__s2)
148 __THROW __attribute_pure__ __nonnull ((1, 2));
149 /* Put a transformation of SRC into no more than N bytes of DEST. */
150 extern size_t strxfrm (char *__restrict __dest,
151 const char *__restrict __src, size_t __n)
152 __THROW __nonnull ((2));
153 __END_NAMESPACE_STD
155 #ifdef __USE_XOPEN2K8
156 /* The following functions are equivalent to the both above but they
157 take the locale they use for the collation as an extra argument.
158 This is not standardsized but something like will come. */
159 # include <xlocale.h>
161 /* Compare the collated forms of S1 and S2 using rules from L. */
162 extern int strcoll_l (const char *__s1, const char *__s2, __locale_t __l)
163 __THROW __attribute_pure__ __nonnull ((1, 2, 3));
164 /* Put a transformation of SRC into no more than N bytes of DEST. */
165 extern size_t strxfrm_l (char *__dest, const char *__src, size_t __n,
166 __locale_t __l) __THROW __nonnull ((2, 4));
167 #endif
169 #if defined __USE_SVID || defined __USE_BSD || defined __USE_XOPEN_EXTENDED \
170 || defined __USE_XOPEN2K8
171 /* Duplicate S, returning an identical malloc'd string. */
172 extern char *strdup (const char *__s)
173 __THROW __attribute_malloc__ __nonnull ((1));
174 #endif
176 /* Return a malloc'd copy of at most N bytes of STRING. The
177 resultant string is terminated even if no null terminator
178 appears before STRING[N]. */
179 #if defined __USE_XOPEN2K8
180 extern char *strndup (const char *__string, size_t __n)
181 __THROW __attribute_malloc__ __nonnull ((1));
182 #endif
184 #if defined __USE_GNU && defined __GNUC__
185 /* Duplicate S, returning an identical alloca'd string. */
186 # define strdupa(s) \
187 (__extension__ \
188 ({ \
189 const char *__old = (s); \
190 size_t __len = strlen (__old) + 1; \
191 char *__new = (char *) __builtin_alloca (__len); \
192 (char *) memcpy (__new, __old, __len); \
195 /* Return an alloca'd copy of at most N bytes of string. */
196 # define strndupa(s, n) \
197 (__extension__ \
198 ({ \
199 const char *__old = (s); \
200 size_t __len = strnlen (__old, (n)); \
201 char *__new = (char *) __builtin_alloca (__len + 1); \
202 __new[__len] = '\0'; \
203 (char *) memcpy (__new, __old, __len); \
205 #endif
207 __BEGIN_NAMESPACE_STD
208 /* Find the first occurrence of C in S. */
209 #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
210 extern "C++"
212 extern char *strchr (char *__s, int __c)
213 __THROW __asm ("strchr") __attribute_pure__ __nonnull ((1));
214 extern const char *strchr (const char *__s, int __c)
215 __THROW __asm ("strchr") __attribute_pure__ __nonnull ((1));
217 # ifdef __OPTIMIZE__
218 __extern_always_inline char *
219 strchr (char *__s, int __c) __THROW
221 return __builtin_strchr (__s, __c);
224 __extern_always_inline const char *
225 strchr (const char *__s, int __c) __THROW
227 return __builtin_strchr (__s, __c);
229 # endif
231 #else
232 extern char *strchr (const char *__s, int __c)
233 __THROW __attribute_pure__ __nonnull ((1));
234 #endif
235 /* Find the last occurrence of C in S. */
236 #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
237 extern "C++"
239 extern char *strrchr (char *__s, int __c)
240 __THROW __asm ("strrchr") __attribute_pure__ __nonnull ((1));
241 extern const char *strrchr (const char *__s, int __c)
242 __THROW __asm ("strrchr") __attribute_pure__ __nonnull ((1));
244 # ifdef __OPTIMIZE__
245 __extern_always_inline char *
246 strrchr (char *__s, int __c) __THROW
248 return __builtin_strrchr (__s, __c);
251 __extern_always_inline const char *
252 strrchr (const char *__s, int __c) __THROW
254 return __builtin_strrchr (__s, __c);
256 # endif
258 #else
259 extern char *strrchr (const char *__s, int __c)
260 __THROW __attribute_pure__ __nonnull ((1));
261 #endif
262 __END_NAMESPACE_STD
264 #ifdef __USE_GNU
265 /* This function is similar to `strchr'. But it returns a pointer to
266 the closing NUL byte in case C is not found in S. */
267 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
268 extern "C++" char *strchrnul (char *__s, int __c)
269 __THROW __asm ("strchrnul") __attribute_pure__ __nonnull ((1));
270 extern "C++" const char *strchrnul (const char *__s, int __c)
271 __THROW __asm ("strchrnul") __attribute_pure__ __nonnull ((1));
272 # else
273 extern char *strchrnul (const char *__s, int __c)
274 __THROW __attribute_pure__ __nonnull ((1));
275 # endif
276 #endif
278 __BEGIN_NAMESPACE_STD
279 /* Return the length of the initial segment of S which
280 consists entirely of characters not in REJECT. */
281 extern size_t strcspn (const char *__s, const char *__reject)
282 __THROW __attribute_pure__ __nonnull ((1, 2));
283 /* Return the length of the initial segment of S which
284 consists entirely of characters in ACCEPT. */
285 extern size_t strspn (const char *__s, const char *__accept)
286 __THROW __attribute_pure__ __nonnull ((1, 2));
287 /* Find the first occurrence in S of any character in ACCEPT. */
288 #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
289 extern "C++"
291 extern char *strpbrk (char *__s, const char *__accept)
292 __THROW __asm ("strpbrk") __attribute_pure__ __nonnull ((1, 2));
293 extern const char *strpbrk (const char *__s, const char *__accept)
294 __THROW __asm ("strpbrk") __attribute_pure__ __nonnull ((1, 2));
296 # ifdef __OPTIMIZE__
297 __extern_always_inline char *
298 strpbrk (char *__s, const char *__accept) __THROW
300 return __builtin_strpbrk (__s, __accept);
303 __extern_always_inline const char *
304 strpbrk (const char *__s, const char *__accept) __THROW
306 return __builtin_strpbrk (__s, __accept);
308 # endif
310 #else
311 extern char *strpbrk (const char *__s, const char *__accept)
312 __THROW __attribute_pure__ __nonnull ((1, 2));
313 #endif
314 /* Find the first occurrence of NEEDLE in HAYSTACK. */
315 #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
316 extern "C++"
318 extern char *strstr (char *__haystack, const char *__needle)
319 __THROW __asm ("strstr") __attribute_pure__ __nonnull ((1, 2));
320 extern const char *strstr (const char *__haystack, const char *__needle)
321 __THROW __asm ("strstr") __attribute_pure__ __nonnull ((1, 2));
323 # ifdef __OPTIMIZE__
324 __extern_always_inline char *
325 strstr (char *__haystack, const char *__needle) __THROW
327 return __builtin_strstr (__haystack, __needle);
330 __extern_always_inline const char *
331 strstr (const char *__haystack, const char *__needle) __THROW
333 return __builtin_strstr (__haystack, __needle);
335 # endif
337 #else
338 extern char *strstr (const char *__haystack, const char *__needle)
339 __THROW __attribute_pure__ __nonnull ((1, 2));
340 #endif
343 /* Divide S into tokens separated by characters in DELIM. */
344 extern char *strtok (char *__restrict __s, const char *__restrict __delim)
345 __THROW __nonnull ((2));
346 __END_NAMESPACE_STD
348 /* Divide S into tokens separated by characters in DELIM. Information
349 passed between calls are stored in SAVE_PTR. */
350 extern char *__strtok_r (char *__restrict __s,
351 const char *__restrict __delim,
352 char **__restrict __save_ptr)
353 __THROW __nonnull ((2, 3));
354 #if defined __USE_POSIX || defined __USE_MISC
355 extern char *strtok_r (char *__restrict __s, const char *__restrict __delim,
356 char **__restrict __save_ptr)
357 __THROW __nonnull ((2, 3));
358 #endif
360 #ifdef __USE_GNU
361 /* Similar to `strstr' but this function ignores the case of both strings. */
362 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
363 extern "C++" char *strcasestr (char *__haystack, const char *__needle)
364 __THROW __asm ("strcasestr") __attribute_pure__ __nonnull ((1, 2));
365 extern "C++" const char *strcasestr (const char *__haystack,
366 const char *__needle)
367 __THROW __asm ("strcasestr") __attribute_pure__ __nonnull ((1, 2));
368 # else
369 extern char *strcasestr (const char *__haystack, const char *__needle)
370 __THROW __attribute_pure__ __nonnull ((1, 2));
371 # endif
372 #endif
374 #ifdef __USE_GNU
375 /* Find the first occurrence of NEEDLE in HAYSTACK.
376 NEEDLE is NEEDLELEN bytes long;
377 HAYSTACK is HAYSTACKLEN bytes long. */
378 extern void *memmem (const void *__haystack, size_t __haystacklen,
379 const void *__needle, size_t __needlelen)
380 __THROW __attribute_pure__ __nonnull ((1, 3));
382 /* Copy N bytes of SRC to DEST, return pointer to bytes after the
383 last written byte. */
384 extern void *__mempcpy (void *__restrict __dest,
385 const void *__restrict __src, size_t __n)
386 __THROW __nonnull ((1, 2));
387 extern void *mempcpy (void *__restrict __dest,
388 const void *__restrict __src, size_t __n)
389 __THROW __nonnull ((1, 2));
390 #endif
393 __BEGIN_NAMESPACE_STD
394 /* Return the length of S. */
395 extern size_t strlen (const char *__s)
396 __THROW __attribute_pure__ __nonnull ((1));
397 __END_NAMESPACE_STD
399 #ifdef __USE_XOPEN2K8
400 /* Find the length of STRING, but scan at most MAXLEN characters.
401 If no '\0' terminator is found in that many characters, return MAXLEN. */
402 extern size_t strnlen (const char *__string, size_t __maxlen)
403 __THROW __attribute_pure__ __nonnull ((1));
404 #endif
407 __BEGIN_NAMESPACE_STD
408 /* Return a string describing the meaning of the `errno' code in ERRNUM. */
409 extern char *strerror (int __errnum) __THROW;
410 __END_NAMESPACE_STD
411 #if defined __USE_XOPEN2K || defined __USE_MISC
412 /* Reentrant version of `strerror'.
413 There are 2 flavors of `strerror_r', GNU which returns the string
414 and may or may not use the supplied temporary buffer and POSIX one
415 which fills the string into the buffer.
416 To use the POSIX version, -D_XOPEN_SOURCE=600 or -D_POSIX_C_SOURCE=200112L
417 without -D_GNU_SOURCE is needed, otherwise the GNU version is
418 preferred. */
419 # if defined __USE_XOPEN2K && !defined __USE_GNU
420 /* Fill BUF with a string describing the meaning of the `errno' code in
421 ERRNUM. */
422 # ifdef __REDIRECT_NTH
423 extern int __REDIRECT_NTH (strerror_r,
424 (int __errnum, char *__buf, size_t __buflen),
425 __xpg_strerror_r) __nonnull ((2));
426 # else
427 extern int __xpg_strerror_r (int __errnum, char *__buf, size_t __buflen)
428 __THROW __nonnull ((2));
429 # define strerror_r __xpg_strerror_r
430 # endif
431 # else
432 /* If a temporary buffer is required, at most BUFLEN bytes of BUF will be
433 used. */
434 extern char *strerror_r (int __errnum, char *__buf, size_t __buflen)
435 __THROW __nonnull ((2)) __wur;
436 # endif
437 #endif
439 #ifdef __USE_XOPEN2K8
440 /* Translate error number to string according to the locale L. */
441 extern char *strerror_l (int __errnum, __locale_t __l) __THROW;
442 #endif
445 /* We define this function always since `bzero' is sometimes needed when
446 the namespace rules does not allow this. */
447 extern void __bzero (void *__s, size_t __n) __THROW __nonnull ((1));
449 #ifdef __USE_BSD
450 /* Copy N bytes of SRC to DEST (like memmove, but args reversed). */
451 extern void bcopy (const void *__src, void *__dest, size_t __n)
452 __THROW __nonnull ((1, 2));
454 /* Set N bytes of S to 0. */
455 extern void bzero (void *__s, size_t __n) __THROW __nonnull ((1));
457 /* Compare N bytes of S1 and S2 (same as memcmp). */
458 extern int bcmp (const void *__s1, const void *__s2, size_t __n)
459 __THROW __attribute_pure__ __nonnull ((1, 2));
461 /* Find the first occurrence of C in S (same as strchr). */
462 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
463 extern "C++"
465 extern char *index (char *__s, int __c)
466 __THROW __asm ("index") __attribute_pure__ __nonnull ((1));
467 extern const char *index (const char *__s, int __c)
468 __THROW __asm ("index") __attribute_pure__ __nonnull ((1));
470 # if defined __OPTIMIZE__ && !defined __CORRECT_ISO_CPP_STRINGS_H_PROTO
471 __extern_always_inline char *
472 index (char *__s, int __c) __THROW
474 return __builtin_index (__s, __c);
477 __extern_always_inline const char *
478 index (const char *__s, int __c) __THROW
480 return __builtin_index (__s, __c);
482 # endif
484 # else
485 extern char *index (const char *__s, int __c)
486 __THROW __attribute_pure__ __nonnull ((1));
487 # endif
489 /* Find the last occurrence of C in S (same as strrchr). */
490 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
491 extern "C++"
493 extern char *rindex (char *__s, int __c)
494 __THROW __asm ("rindex") __attribute_pure__ __nonnull ((1));
495 extern const char *rindex (const char *__s, int __c)
496 __THROW __asm ("rindex") __attribute_pure__ __nonnull ((1));
498 # if defined __OPTIMIZE__ && !defined __CORRECT_ISO_CPP_STRINGS_H_PROTO
499 __extern_always_inline char *
500 rindex (char *__s, int __c) __THROW
502 return __builtin_rindex (__s, __c);
505 __extern_always_inline const char *
506 rindex (const char *__s, int __c) __THROW
508 return __builtin_rindex (__s, __c);
510 #endif
512 # else
513 extern char *rindex (const char *__s, int __c)
514 __THROW __attribute_pure__ __nonnull ((1));
515 # endif
517 /* Return the position of the first bit set in I, or 0 if none are set.
518 The least-significant bit is position 1, the most-significant 32. */
519 extern int ffs (int __i) __THROW __attribute__ ((__const__));
521 /* The following two functions are non-standard but necessary for non-32 bit
522 platforms. */
523 # ifdef __USE_GNU
524 extern int ffsl (long int __l) __THROW __attribute__ ((__const__));
525 # ifdef __GNUC__
526 __extension__ extern int ffsll (long long int __ll)
527 __THROW __attribute__ ((__const__));
528 # endif
529 # endif
531 /* Compare S1 and S2, ignoring case. */
532 extern int strcasecmp (const char *__s1, const char *__s2)
533 __THROW __attribute_pure__ __nonnull ((1, 2));
535 /* Compare no more than N chars of S1 and S2, ignoring case. */
536 extern int strncasecmp (const char *__s1, const char *__s2, size_t __n)
537 __THROW __attribute_pure__ __nonnull ((1, 2));
538 #endif /* Use BSD. */
540 #ifdef __USE_GNU
541 /* Again versions of a few functions which use the given locale instead
542 of the global one. */
543 extern int strcasecmp_l (const char *__s1, const char *__s2,
544 __locale_t __loc)
545 __THROW __attribute_pure__ __nonnull ((1, 2, 3));
547 extern int strncasecmp_l (const char *__s1, const char *__s2,
548 size_t __n, __locale_t __loc)
549 __THROW __attribute_pure__ __nonnull ((1, 2, 4));
550 #endif
552 #ifdef __USE_BSD
553 /* Return the next DELIM-delimited token from *STRINGP,
554 terminating it with a '\0', and update *STRINGP to point past it. */
555 extern char *strsep (char **__restrict __stringp,
556 const char *__restrict __delim)
557 __THROW __nonnull ((1, 2));
558 #endif
560 #ifdef __USE_XOPEN2K8
561 /* Return a string describing the meaning of the signal number in SIG. */
562 extern char *strsignal (int __sig) __THROW;
564 /* Copy SRC to DEST, returning the address of the terminating '\0' in DEST. */
565 extern char *__stpcpy (char *__restrict __dest, const char *__restrict __src)
566 __THROW __nonnull ((1, 2));
567 extern char *stpcpy (char *__restrict __dest, const char *__restrict __src)
568 __THROW __nonnull ((1, 2));
570 /* Copy no more than N characters of SRC to DEST, returning the address of
571 the last character written into DEST. */
572 extern char *__stpncpy (char *__restrict __dest,
573 const char *__restrict __src, size_t __n)
574 __THROW __nonnull ((1, 2));
575 extern char *stpncpy (char *__restrict __dest,
576 const char *__restrict __src, size_t __n)
577 __THROW __nonnull ((1, 2));
578 #endif
580 #ifdef __USE_GNU
581 /* Compare S1 and S2 as strings holding name & indices/version numbers. */
582 extern int strverscmp (const char *__s1, const char *__s2)
583 __THROW __attribute_pure__ __nonnull ((1, 2));
585 /* Sautee STRING briskly. */
586 extern char *strfry (char *__string) __THROW __nonnull ((1));
588 /* Frobnicate N bytes of S. */
589 extern void *memfrob (void *__s, size_t __n) __THROW __nonnull ((1));
591 # ifndef basename
592 /* Return the file name within directory of FILENAME. We don't
593 declare the function if the `basename' macro is available (defined
594 in <libgen.h>) which makes the XPG version of this function
595 available. */
596 # ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
597 extern "C++" char *basename (char *__filename)
598 __THROW __asm ("basename") __nonnull ((1));
599 extern "C++" const char *basename (const char *__filename)
600 __THROW __asm ("basename") __nonnull ((1));
601 # else
602 extern char *basename (const char *__filename) __THROW __nonnull ((1));
603 # endif
604 # endif
605 #endif
608 #if defined __GNUC__ && __GNUC__ >= 2
609 # if defined __OPTIMIZE__ && !defined __OPTIMIZE_SIZE__ \
610 && !defined __NO_INLINE__ && !defined __cplusplus
611 /* When using GNU CC we provide some optimized versions of selected
612 functions from this header. There are two kinds of optimizations:
614 - machine-dependent optimizations, most probably using inline
615 assembler code; these might be quite expensive since the code
616 size can increase significantly.
617 These optimizations are not used unless the symbol
618 __USE_STRING_INLINES
619 is defined before including this header.
621 - machine-independent optimizations which do not increase the
622 code size significantly and which optimize mainly situations
623 where one or more arguments are compile-time constants.
624 These optimizations are used always when the compiler is
625 taught to optimize.
627 One can inhibit all optimizations by defining __NO_STRING_INLINES. */
629 /* Get the machine-dependent optimizations (if any). */
630 # include <bits/string.h>
632 /* These are generic optimizations which do not add too much inline code. */
633 # include <bits/string2.h>
634 # endif
636 # if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
637 /* Functions with security checks. */
638 # include <bits/string3.h>
639 # endif
640 #endif
642 __END_DECLS
644 #endif /* string.h */