gl/string.in.h

   1 /* A GNU-like <string.h>.
   2
   3    Copyright (C) 1995-1996, 2001-2009 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3, or (at your option)
   8    any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software Foundation,
  17    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  18
  19 #ifndef _GL_STRING_H
  20
  21 #if __GNUC__ >= 3
  22 @PRAGMA_SYSTEM_HEADER@
  23 #endif
  24
  25 /* The include_next requires a split double-inclusion guard.  */
  26 #@INCLUDE_NEXT@ @NEXT_STRING_H@
  27
  28 #ifndef _GL_STRING_H
  29 #define _GL_STRING_H
  30
  31 /* NetBSD 5.0 mis-defines NULL.  */
  32 #include <stddef.h>
  33
  34 #ifndef __attribute__
  35 /* This feature is available in gcc versions 2.5 and later.  */
  36 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5)
  37 #  define __attribute__(Spec) /* empty */
  38 # endif
  39 /* The attribute __pure__ was added in gcc 2.96.  */
  40 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 96)
  41 #  define __pure__ /* empty */
  42 # endif
  43 #endif
  44
  45
  46 /* The definition of GL_LINK_WARNING is copied here.  */
  47
  48
  49 #ifdef __cplusplus
  50 extern "C" {
  51 #endif
  52
  53
  54 /* Return the first instance of C within N bytes of S, or NULL.  */
  55 #if @GNULIB_MEMCHR@
  56 # if @REPLACE_MEMCHR@
  57 #  define memchr rpl_memchr
  58 extern void *memchr (void const *__s, int __c, size_t __n)
  59   __attribute__ ((__pure__));
  60 # endif
  61 #elif defined GNULIB_POSIXCHECK
  62 # undef memchr
  63 # define memchr(s,c,n) \
  64     (GL_LINK_WARNING ("memchr has platform-specific bugs - " \
  65                       "use gnulib module memchr for portability" ), \
  66      memchr (s, c, n))
  67 #endif
  68
  69 /* Return the first occurrence of NEEDLE in HAYSTACK.  */
  70 #if @GNULIB_MEMMEM@
  71 # if @REPLACE_MEMMEM@
  72 #  define memmem rpl_memmem
  73 # endif
  74 # if ! @HAVE_DECL_MEMMEM@ || @REPLACE_MEMMEM@
  75 extern void *memmem (void const *__haystack, size_t __haystack_len,
  76                      void const *__needle, size_t __needle_len)
  77   __attribute__ ((__pure__));
  78 # endif
  79 #elif defined GNULIB_POSIXCHECK
  80 # undef memmem
  81 # define memmem(a,al,b,bl) \
  82     (GL_LINK_WARNING ("memmem is unportable and often quadratic - " \
  83                       "use gnulib module memmem-simple for portability, " \
  84                       "and module memmem for speed" ), \
  85      memmem (a, al, b, bl))
  86 #endif
  87
  88 /* Copy N bytes of SRC to DEST, return pointer to bytes after the
  89    last written byte.  */
  90 #if @GNULIB_MEMPCPY@
  91 # if ! @HAVE_MEMPCPY@
  92 extern void *mempcpy (void *restrict __dest, void const *restrict __src,
  93                       size_t __n);
  94 # endif
  95 #elif defined GNULIB_POSIXCHECK
  96 # undef mempcpy
  97 # define mempcpy(a,b,n) \
  98     (GL_LINK_WARNING ("mempcpy is unportable - " \
  99                       "use gnulib module mempcpy for portability"), \
 100      mempcpy (a, b, n))
 101 #endif
 102
 103 /* Search backwards through a block for a byte (specified as an int).  */
 104 #if @GNULIB_MEMRCHR@
 105 # if ! @HAVE_DECL_MEMRCHR@
 106 extern void *memrchr (void const *, int, size_t)
 107   __attribute__ ((__pure__));
 108 # endif
 109 #elif defined GNULIB_POSIXCHECK
 110 # undef memrchr
 111 # define memrchr(a,b,c) \
 112     (GL_LINK_WARNING ("memrchr is unportable - " \
 113                       "use gnulib module memrchr for portability"), \
 114      memrchr (a, b, c))
 115 #endif
 116
 117 /* Find the first occurrence of C in S.  More efficient than
 118    memchr(S,C,N), at the expense of undefined behavior if C does not
 119    occur within N bytes.  */
 120 #if @GNULIB_RAWMEMCHR@
 121 # if ! @HAVE_RAWMEMCHR@
 122 extern void *rawmemchr (void const *__s, int __c_in)
 123   __attribute__ ((__pure__));
 124 # endif
 125 #elif defined GNULIB_POSIXCHECK
 126 # undef rawmemchr
 127 # define rawmemchr(a,b) \
 128     (GL_LINK_WARNING ("rawmemchr is unportable - " \
 129                       "use gnulib module rawmemchr for portability"), \
 130      rawmemchr (a, b))
 131 #endif
 132
 133 /* Copy SRC to DST, returning the address of the terminating '\0' in DST.  */
 134 #if @GNULIB_STPCPY@
 135 # if ! @HAVE_STPCPY@
 136 extern char *stpcpy (char *restrict __dst, char const *restrict __src);
 137 # endif
 138 #elif defined GNULIB_POSIXCHECK
 139 # undef stpcpy
 140 # define stpcpy(a,b) \
 141     (GL_LINK_WARNING ("stpcpy is unportable - " \
 142                       "use gnulib module stpcpy for portability"), \
 143      stpcpy (a, b))
 144 #endif
 145
 146 /* Copy no more than N bytes of SRC to DST, returning a pointer past the
 147    last non-NUL byte written into DST.  */
 148 #if @GNULIB_STPNCPY@
 149 # if ! @HAVE_STPNCPY@
 150 #  define stpncpy gnu_stpncpy
 151 extern char *stpncpy (char *restrict __dst, char const *restrict __src,
 152                       size_t __n);
 153 # endif
 154 #elif defined GNULIB_POSIXCHECK
 155 # undef stpncpy
 156 # define stpncpy(a,b,n) \
 157     (GL_LINK_WARNING ("stpncpy is unportable - " \
 158                       "use gnulib module stpncpy for portability"), \
 159      stpncpy (a, b, n))
 160 #endif
 161
 162 #if defined GNULIB_POSIXCHECK
 163 /* strchr() does not work with multibyte strings if the locale encoding is
 164    GB18030 and the character to be searched is a digit.  */
 165 # undef strchr
 166 # define strchr(s,c) \
 167     (GL_LINK_WARNING ("strchr cannot work correctly on character strings " \
 168                       "in some multibyte locales - " \
 169                       "use mbschr if you care about internationalization"), \
 170      strchr (s, c))
 171 #endif
 172
 173 /* Find the first occurrence of C in S or the final NUL byte.  */
 174 #if @GNULIB_STRCHRNUL@
 175 # if ! @HAVE_STRCHRNUL@
 176 extern char *strchrnul (char const *__s, int __c_in)
 177   __attribute__ ((__pure__));
 178 # endif
 179 #elif defined GNULIB_POSIXCHECK
 180 # undef strchrnul
 181 # define strchrnul(a,b) \
 182     (GL_LINK_WARNING ("strchrnul is unportable - " \
 183                       "use gnulib module strchrnul for portability"), \
 184      strchrnul (a, b))
 185 #endif
 186
 187 /* Duplicate S, returning an identical malloc'd string.  */
 188 #if @GNULIB_STRDUP@
 189 # if @REPLACE_STRDUP@
 190 #  undef strdup
 191 #  define strdup rpl_strdup
 192 # endif
 193 # if !(@HAVE_DECL_STRDUP@ || defined strdup) || @REPLACE_STRDUP@
 194 extern char *strdup (char const *__s);
 195 # endif
 196 #elif defined GNULIB_POSIXCHECK
 197 # undef strdup
 198 # define strdup(a) \
 199     (GL_LINK_WARNING ("strdup is unportable - " \
 200                       "use gnulib module strdup for portability"), \
 201      strdup (a))
 202 #endif
 203
 204 /* Return a newly allocated copy of at most N bytes of STRING.  */
 205 #if @GNULIB_STRNDUP@
 206 # if @REPLACE_STRNDUP@
 207 #  undef strndup
 208 #  define strndup rpl_strndup
 209 # endif
 210 # if @REPLACE_STRNDUP@ || ! @HAVE_DECL_STRNDUP@
 211 extern char *strndup (char const *__string, size_t __n);
 212 # endif
 213 #elif defined GNULIB_POSIXCHECK
 214 # undef strndup
 215 # define strndup(a,n) \
 216     (GL_LINK_WARNING ("strndup is unportable - " \
 217                       "use gnulib module strndup for portability"), \
 218      strndup (a, n))
 219 #endif
 220
 221 /* Find the length (number of bytes) of STRING, but scan at most
 222    MAXLEN bytes.  If no '\0' terminator is found in that many bytes,
 223    return MAXLEN.  */
 224 #if @GNULIB_STRNLEN@
 225 # if ! @HAVE_DECL_STRNLEN@
 226 extern size_t strnlen (char const *__string, size_t __maxlen)
 227   __attribute__ ((__pure__));
 228 # endif
 229 #elif defined GNULIB_POSIXCHECK
 230 # undef strnlen
 231 # define strnlen(a,n) \
 232     (GL_LINK_WARNING ("strnlen is unportable - " \
 233                       "use gnulib module strnlen for portability"), \
 234      strnlen (a, n))
 235 #endif
 236
 237 #if defined GNULIB_POSIXCHECK
 238 /* strcspn() assumes the second argument is a list of single-byte characters.
 239    Even in this simple case, it does not work with multibyte strings if the
 240    locale encoding is GB18030 and one of the characters to be searched is a
 241    digit.  */
 242 # undef strcspn
 243 # define strcspn(s,a) \
 244     (GL_LINK_WARNING ("strcspn cannot work correctly on character strings " \
 245                       "in multibyte locales - " \
 246                       "use mbscspn if you care about internationalization"), \
 247      strcspn (s, a))
 248 #endif
 249
 250 /* Find the first occurrence in S of any character in ACCEPT.  */
 251 #if @GNULIB_STRPBRK@
 252 # if ! @HAVE_STRPBRK@
 253 extern char *strpbrk (char const *__s, char const *__accept)
 254   __attribute__ ((__pure__));
 255 # endif
 256 # if defined GNULIB_POSIXCHECK
 257 /* strpbrk() assumes the second argument is a list of single-byte characters.
 258    Even in this simple case, it does not work with multibyte strings if the
 259    locale encoding is GB18030 and one of the characters to be searched is a
 260    digit.  */
 261 #  undef strpbrk
 262 #  define strpbrk(s,a) \
 263      (GL_LINK_WARNING ("strpbrk cannot work correctly on character strings " \
 264                        "in multibyte locales - " \
 265                        "use mbspbrk if you care about internationalization"), \
 266       strpbrk (s, a))
 267 # endif
 268 #elif defined GNULIB_POSIXCHECK
 269 # undef strpbrk
 270 # define strpbrk(s,a) \
 271     (GL_LINK_WARNING ("strpbrk is unportable - " \
 272                       "use gnulib module strpbrk for portability"), \
 273      strpbrk (s, a))
 274 #endif
 275
 276 #if defined GNULIB_POSIXCHECK
 277 /* strspn() assumes the second argument is a list of single-byte characters.
 278    Even in this simple case, it cannot work with multibyte strings.  */
 279 # undef strspn
 280 # define strspn(s,a) \
 281     (GL_LINK_WARNING ("strspn cannot work correctly on character strings " \
 282                       "in multibyte locales - " \
 283                       "use mbsspn if you care about internationalization"), \
 284      strspn (s, a))
 285 #endif
 286
 287 #if defined GNULIB_POSIXCHECK
 288 /* strrchr() does not work with multibyte strings if the locale encoding is
 289    GB18030 and the character to be searched is a digit.  */
 290 # undef strrchr
 291 # define strrchr(s,c) \
 292     (GL_LINK_WARNING ("strrchr cannot work correctly on character strings " \
 293                       "in some multibyte locales - " \
 294                       "use mbsrchr if you care about internationalization"), \
 295      strrchr (s, c))
 296 #endif
 297
 298 /* Search the next delimiter (char listed in DELIM) starting at *STRINGP.
 299    If one is found, overwrite it with a NUL, and advance *STRINGP
 300    to point to the next char after it.  Otherwise, set *STRINGP to NULL.
 301    If *STRINGP was already NULL, nothing happens.
 302    Return the old value of *STRINGP.
 303
 304    This is a variant of strtok() that is multithread-safe and supports
 305    empty fields.
 306
 307    Caveat: It modifies the original string.
 308    Caveat: These functions cannot be used on constant strings.
 309    Caveat: The identity of the delimiting character is lost.
 310    Caveat: It doesn't work with multibyte strings unless all of the delimiter
 311            characters are ASCII characters < 0x30.
 312
 313    See also strtok_r().  */
 314 #if @GNULIB_STRSEP@
 315 # if ! @HAVE_STRSEP@
 316 extern char *strsep (char **restrict __stringp, char const *restrict __delim);
 317 # endif
 318 # if defined GNULIB_POSIXCHECK
 319 #  undef strsep
 320 #  define strsep(s,d) \
 321      (GL_LINK_WARNING ("strsep cannot work correctly on character strings " \
 322                        "in multibyte locales - " \
 323                        "use mbssep if you care about internationalization"), \
 324       strsep (s, d))
 325 # endif
 326 #elif defined GNULIB_POSIXCHECK
 327 # undef strsep
 328 # define strsep(s,d) \
 329     (GL_LINK_WARNING ("strsep is unportable - " \
 330                       "use gnulib module strsep for portability"), \
 331      strsep (s, d))
 332 #endif
 333
 334 #if @GNULIB_STRSTR@
 335 # if @REPLACE_STRSTR@
 336 #  define strstr rpl_strstr
 337 char *strstr (const char *haystack, const char *needle)
 338   __attribute__ ((__pure__));
 339 # endif
 340 #elif defined GNULIB_POSIXCHECK
 341 /* strstr() does not work with multibyte strings if the locale encoding is
 342    different from UTF-8:
 343    POSIX says that it operates on "strings", and "string" in POSIX is defined
 344    as a sequence of bytes, not of characters.  */
 345 # undef strstr
 346 # define strstr(a,b) \
 347     (GL_LINK_WARNING ("strstr is quadratic on many systems, and cannot " \
 348                       "work correctly on character strings in most "    \
 349                       "multibyte locales - " \
 350                       "use mbsstr if you care about internationalization, " \
 351                       "or use strstr if you care about speed"), \
 352      strstr (a, b))
 353 #endif
 354
 355 /* Find the first occurrence of NEEDLE in HAYSTACK, using case-insensitive
 356    comparison.  */
 357 #if @GNULIB_STRCASESTR@
 358 # if @REPLACE_STRCASESTR@
 359 #  define strcasestr rpl_strcasestr
 360 # endif
 361 # if ! @HAVE_STRCASESTR@ || @REPLACE_STRCASESTR@
 362 extern char *strcasestr (const char *haystack, const char *needle)
 363   __attribute__ ((__pure__));
 364 # endif
 365 #elif defined GNULIB_POSIXCHECK
 366 /* strcasestr() does not work with multibyte strings:
 367    It is a glibc extension, and glibc implements it only for unibyte
 368    locales.  */
 369 # undef strcasestr
 370 # define strcasestr(a,b) \
 371     (GL_LINK_WARNING ("strcasestr does work correctly on character strings " \
 372                       "in multibyte locales - " \
 373                       "use mbscasestr if you care about " \
 374                       "internationalization, or use c-strcasestr if you want " \
 375                       "a locale independent function"), \
 376      strcasestr (a, b))
 377 #endif
 378
 379 /* Parse S into tokens separated by characters in DELIM.
 380    If S is NULL, the saved pointer in SAVE_PTR is used as
 381    the next starting point.  For example:
 382         char s[] = "-abc-=-def";
 383         char *sp;
 384         x = strtok_r(s, "-", &sp);      // x = "abc", sp = "=-def"
 385         x = strtok_r(NULL, "-=", &sp);  // x = "def", sp = NULL
 386         x = strtok_r(NULL, "=", &sp);   // x = NULL
 387                 // s = "abc\0-def\0"
 388
 389    This is a variant of strtok() that is multithread-safe.
 390
 391    For the POSIX documentation for this function, see:
 392    http://www.opengroup.org/susv3xsh/strtok.html
 393
 394    Caveat: It modifies the original string.
 395    Caveat: These functions cannot be used on constant strings.
 396    Caveat: The identity of the delimiting character is lost.
 397    Caveat: It doesn't work with multibyte strings unless all of the delimiter
 398            characters are ASCII characters < 0x30.
 399
 400    See also strsep().  */
 401 #if @GNULIB_STRTOK_R@
 402 # if @REPLACE_STRTOK_R@
 403 #  undef strtok_r
 404 #  define strtok_r rpl_strtok_r
 405 # elif @UNDEFINE_STRTOK_R@
 406 #  undef strtok_r
 407 # endif
 408 # if ! @HAVE_DECL_STRTOK_R@ || @REPLACE_STRTOK_R@
 409 extern char *strtok_r (char *restrict s, char const *restrict delim,
 410                        char **restrict save_ptr);
 411 # endif
 412 # if defined GNULIB_POSIXCHECK
 413 #  undef strtok_r
 414 #  define strtok_r(s,d,p) \
 415      (GL_LINK_WARNING ("strtok_r cannot work correctly on character strings " \
 416                        "in multibyte locales - " \
 417                        "use mbstok_r if you care about internationalization"), \
 418       strtok_r (s, d, p))
 419 # endif
 420 #elif defined GNULIB_POSIXCHECK
 421 # undef strtok_r
 422 # define strtok_r(s,d,p) \
 423     (GL_LINK_WARNING ("strtok_r is unportable - " \
 424                       "use gnulib module strtok_r for portability"), \
 425      strtok_r (s, d, p))
 426 #endif
 427
 428
 429 /* The following functions are not specified by POSIX.  They are gnulib
 430    extensions.  */
 431
 432 #if @GNULIB_MBSLEN@
 433 /* Return the number of multibyte characters in the character string STRING.
 434    This considers multibyte characters, unlike strlen, which counts bytes.  */
 435 extern size_t mbslen (const char *string);
 436 #endif
 437
 438 #if @GNULIB_MBSNLEN@
 439 /* Return the number of multibyte characters in the character string starting
 440    at STRING and ending at STRING + LEN.  */
 441 extern size_t mbsnlen (const char *string, size_t len);
 442 #endif
 443
 444 #if @GNULIB_MBSCHR@
 445 /* Locate the first single-byte character C in the character string STRING,
 446    and return a pointer to it.  Return NULL if C is not found in STRING.
 447    Unlike strchr(), this function works correctly in multibyte locales with
 448    encodings such as GB18030.  */
 449 # define mbschr rpl_mbschr /* avoid collision with HP-UX function */
 450 extern char * mbschr (const char *string, int c);
 451 #endif
 452
 453 #if @GNULIB_MBSRCHR@
 454 /* Locate the last single-byte character C in the character string STRING,
 455    and return a pointer to it.  Return NULL if C is not found in STRING.
 456    Unlike strrchr(), this function works correctly in multibyte locales with
 457    encodings such as GB18030.  */
 458 # define mbsrchr rpl_mbsrchr /* avoid collision with HP-UX function */
 459 extern char * mbsrchr (const char *string, int c);
 460 #endif
 461
 462 #if @GNULIB_MBSSTR@
 463 /* Find the first occurrence of the character string NEEDLE in the character
 464    string HAYSTACK.  Return NULL if NEEDLE is not found in HAYSTACK.
 465    Unlike strstr(), this function works correctly in multibyte locales with
 466    encodings different from UTF-8.  */
 467 extern char * mbsstr (const char *haystack, const char *needle);
 468 #endif
 469
 470 #if @GNULIB_MBSCASECMP@
 471 /* Compare the character strings S1 and S2, ignoring case, returning less than,
 472    equal to or greater than zero if S1 is lexicographically less than, equal to
 473    or greater than S2.
 474    Note: This function may, in multibyte locales, return 0 for strings of
 475    different lengths!
 476    Unlike strcasecmp(), this function works correctly in multibyte locales.  */
 477 extern int mbscasecmp (const char *s1, const char *s2);
 478 #endif
 479
 480 #if @GNULIB_MBSNCASECMP@
 481 /* Compare the initial segment of the character string S1 consisting of at most
 482    N characters with the initial segment of the character string S2 consisting
 483    of at most N characters, ignoring case, returning less than, equal to or
 484    greater than zero if the initial segment of S1 is lexicographically less
 485    than, equal to or greater than the initial segment of S2.
 486    Note: This function may, in multibyte locales, return 0 for initial segments
 487    of different lengths!
 488    Unlike strncasecmp(), this function works correctly in multibyte locales.
 489    But beware that N is not a byte count but a character count!  */
 490 extern int mbsncasecmp (const char *s1, const char *s2, size_t n);
 491 #endif
 492
 493 #if @GNULIB_MBSPCASECMP@
 494 /* Compare the initial segment of the character string STRING consisting of
 495    at most mbslen (PREFIX) characters with the character string PREFIX,
 496    ignoring case, returning less than, equal to or greater than zero if this
 497    initial segment is lexicographically less than, equal to or greater than
 498    PREFIX.
 499    Note: This function may, in multibyte locales, return 0 if STRING is of
 500    smaller length than PREFIX!
 501    Unlike strncasecmp(), this function works correctly in multibyte
 502    locales.  */
 503 extern char * mbspcasecmp (const char *string, const char *prefix);
 504 #endif
 505
 506 #if @GNULIB_MBSCASESTR@
 507 /* Find the first occurrence of the character string NEEDLE in the character
 508    string HAYSTACK, using case-insensitive comparison.
 509    Note: This function may, in multibyte locales, return success even if
 510    strlen (haystack) < strlen (needle) !
 511    Unlike strcasestr(), this function works correctly in multibyte locales.  */
 512 extern char * mbscasestr (const char *haystack, const char *needle);
 513 #endif
 514
 515 #if @GNULIB_MBSCSPN@
 516 /* Find the first occurrence in the character string STRING of any character
 517    in the character string ACCEPT.  Return the number of bytes from the
 518    beginning of the string to this occurrence, or to the end of the string
 519    if none exists.
 520    Unlike strcspn(), this function works correctly in multibyte locales.  */
 521 extern size_t mbscspn (const char *string, const char *accept);
 522 #endif
 523
 524 #if @GNULIB_MBSPBRK@
 525 /* Find the first occurrence in the character string STRING of any character
 526    in the character string ACCEPT.  Return the pointer to it, or NULL if none
 527    exists.
 528    Unlike strpbrk(), this function works correctly in multibyte locales.  */
 529 # define mbspbrk rpl_mbspbrk /* avoid collision with HP-UX function */
 530 extern char * mbspbrk (const char *string, const char *accept);
 531 #endif
 532
 533 #if @GNULIB_MBSSPN@
 534 /* Find the first occurrence in the character string STRING of any character
 535    not in the character string REJECT.  Return the number of bytes from the
 536    beginning of the string to this occurrence, or to the end of the string
 537    if none exists.
 538    Unlike strspn(), this function works correctly in multibyte locales.  */
 539 extern size_t mbsspn (const char *string, const char *reject);
 540 #endif
 541
 542 #if @GNULIB_MBSSEP@
 543 /* Search the next delimiter (multibyte character listed in the character
 544    string DELIM) starting at the character string *STRINGP.
 545    If one is found, overwrite it with a NUL, and advance *STRINGP to point
 546    to the next multibyte character after it.  Otherwise, set *STRINGP to NULL.
 547    If *STRINGP was already NULL, nothing happens.
 548    Return the old value of *STRINGP.
 549
 550    This is a variant of mbstok_r() that supports empty fields.
 551
 552    Caveat: It modifies the original string.
 553    Caveat: These functions cannot be used on constant strings.
 554    Caveat: The identity of the delimiting character is lost.
 555
 556    See also mbstok_r().  */
 557 extern char * mbssep (char **stringp, const char *delim);
 558 #endif
 559
 560 #if @GNULIB_MBSTOK_R@
 561 /* Parse the character string STRING into tokens separated by characters in
 562    the character string DELIM.
 563    If STRING is NULL, the saved pointer in SAVE_PTR is used as
 564    the next starting point.  For example:
 565         char s[] = "-abc-=-def";
 566         char *sp;
 567         x = mbstok_r(s, "-", &sp);      // x = "abc", sp = "=-def"
 568         x = mbstok_r(NULL, "-=", &sp);  // x = "def", sp = NULL
 569         x = mbstok_r(NULL, "=", &sp);   // x = NULL
 570                 // s = "abc\0-def\0"
 571
 572    Caveat: It modifies the original string.
 573    Caveat: These functions cannot be used on constant strings.
 574    Caveat: The identity of the delimiting character is lost.
 575
 576    See also mbssep().  */
 577 extern char * mbstok_r (char *string, const char *delim, char **save_ptr);
 578 #endif
 579
 580 /* Map any int, typically from errno, into an error message.  */
 581 #if @GNULIB_STRERROR@
 582 # if @REPLACE_STRERROR@
 583 #  undef strerror
 584 #  define strerror rpl_strerror
 585 extern char *strerror (int);
 586 # endif
 587 #elif defined GNULIB_POSIXCHECK
 588 # undef strerror
 589 # define strerror(e) \
 590     (GL_LINK_WARNING ("strerror is unportable - " \
 591                       "use gnulib module strerror to guarantee non-NULL result"), \
 592      strerror (e))
 593 #endif
 594
 595 #if @GNULIB_STRSIGNAL@
 596 # if @REPLACE_STRSIGNAL@
 597 #  define strsignal rpl_strsignal
 598 # endif
 599 # if ! @HAVE_DECL_STRSIGNAL@ || @REPLACE_STRSIGNAL@
 600 extern char *strsignal (int __sig);
 601 # endif
 602 #elif defined GNULIB_POSIXCHECK
 603 # undef strsignal
 604 # define strsignal(a) \
 605     (GL_LINK_WARNING ("strsignal is unportable - " \
 606                       "use gnulib module strsignal for portability"), \
 607      strsignal (a))
 608 #endif
 609
 610 #if @GNULIB_STRVERSCMP@
 611 # if !@HAVE_STRVERSCMP@
 612 extern int strverscmp (const char *, const char *);
 613 # endif
 614 #elif defined GNULIB_POSIXCHECK
 615 # undef strverscmp
 616 # define strverscmp(a, b) \
 617     (GL_LINK_WARNING ("strverscmp is unportable - " \
 618                       "use gnulib module strverscmp for portability"), \
 619      strverscmp (a, b))
 620 #endif
 621
 622
 623 #ifdef __cplusplus
 624 }
 625 #endif
 626
 627 #endif /* _GL_STRING_H */
 628 #endif /* _GL_STRING_H */