string/bits/string2.h

   1 /* Machine-independant string function optimizations.
   2    Copyright (C) 1997, 1998 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #ifndef _STRING_H
  22 # error "Never use <bits/string2.h> directly; include <string.h> instead."
  23 #endif
  24
  25 #ifndef __NO_STRING_INLINES
  26
  27 /* Unlike the definitions in the header <bits/string.h> the
  28    definitions contained here are not optimized down to assembler
  29    level.  Those optimizations are not always a good idea since this
  30    means the code size increases a lot.  Instead the definitions here
  31    optimize some functions in a way which do not dramatically
  32    increase the code size and which do not use assembler.  The main
  33    trick is to use GNU CC's `__builtin_constant_p' function.
  34
  35    Every function XXX which has a defined version in
  36    <bits/string.h> must be accompanied by a symbol _HAVE_STRING_ARCH_XXX
  37    to make sure we don't get redefinitions.
  38
  39    We must use here macros instead of inline functions since the
  40    trick won't work with the later.  */
  41
  42 #ifdef __cplusplus
  43 # define __STRING_INLINE inline
  44 #else
  45 # define __STRING_INLINE extern __inline
  46 #endif
  47
  48 #if _STRING_ARCH_unaligned
  49 /* If we can do unaligned memory accesses we must know the endianess.  */
  50 # include <endian.h>
  51 # include <bits/types.h>
  52
  53 # if __BYTE_ORDER == __LITTLE_ENDIAN
  54 #  define __STRING2_SMALL_GET16(src, idx) \
  55      (((__const unsigned char *) (src))[idx + 1] << 8                         \
  56       | ((__const unsigned char *) (src))[idx])
  57 #  define __STRING2_SMALL_GET32(src, idx) \
  58      (((((__const unsigned char *) (src))[idx + 3] << 8                       \
  59         | ((__const char *) (src))[idx + 2]) << 8                             \
  60        | ((__const unsigned char *) (src))[idx + 1]) << 8                     \
  61       | ((__const unsigned char *) (src))[idx])
  62 # else
  63 #  define __STRING2_SMALL_GET16(src, idx) \
  64      (((__const unsigned char *) (src))[idx] << 8                             \
  65       | ((__const unsigned char *) (src))[idx + 1])
  66 #  define __STRING2_SMALL_GET32(src, idx) \
  67      (((((__const unsigned char *) (src))[idx] << 8                           \
  68         | ((__const unsigned char *) (src))[idx + 1]) << 8                    \
  69        | ((__const unsigned char *) (src))[idx + 2]) << 8                     \
  70       | ((__const unsigned char *) (src))[idx + 3])
  71 # endif
  72 #else
  73 /* These are a few types we need for the optimizations if we cannot
  74    use unaligned memory accesses.  */
  75 # define __STRING2_COPY_TYPE(N) \
  76   typedef struct { char __arr[N]; }                                           \
  77     __STRING2_COPY_ARR##N __attribute__ ((packed))
  78 __STRING2_COPY_TYPE (2);
  79 __STRING2_COPY_TYPE (3);
  80 __STRING2_COPY_TYPE (4);
  81 __STRING2_COPY_TYPE (5);
  82 __STRING2_COPY_TYPE (6);
  83 __STRING2_COPY_TYPE (7);
  84 __STRING2_COPY_TYPE (8);
  85 # undef __STRING2_COPY_TYPE
  86 #endif
  87
  88 /* Dereferencing a pointer arg to run sizeof on it fails for the
  89    void pointer case, so we use this instead.  Note that the argument
  90    must not contain any side effects.  */
  91 #define __string2_1bptr_p(x) (((size_t) ((x) + 1) - (size_t) (x)) == 1)
  92
  93
  94 /* Set N bytes of S to C.  */
  95 #ifndef _HAVE_STRING_ARCH_memset
  96 # define memset(s, c, n) \
  97   (__extension__ (__builtin_constant_p (c) && (c) == '\0'                     \
  98                   ? ({ void *__s = (s); __bzero (__s, n); __s; })             \
  99                   : memset (s, c, n)))
 100 #endif
 101
 102
 103 /* Copy SRC to DEST.  */
 104 #ifndef _HAVE_STRING_ARCH_strcpy
 105 # define strcpy(dest, src) \
 106   (__extension__ (__builtin_constant_p (src)                                  \
 107                   ? (__string2_1bptr_p (src) && strlen (src) + 1 <= 8         \
 108                      ? __strcpy_small (dest, src, strlen (src) + 1)           \
 109                      : (char *) memcpy (dest, src, strlen (src) + 1))         \
 110                   : strcpy (dest, src)))
 111
 112 # if _STRING_ARCH_unaligned
 113 #  define __strcpy_small(dest, src, srclen) \
 114   (__extension__ ({ unsigned char *__dest = (unsigned char *) (dest);         \
 115                     switch (srclen)                                           \
 116                       {                                                       \
 117                       case 1:                                                 \
 118                         *__dest = '\0';                                       \
 119                         break;                                                \
 120                       case 2:                                                 \
 121                         *((__uint16_t *) __dest) =                            \
 122                           __STRING2_SMALL_GET16 (src, 0);                     \
 123                         break;                                                \
 124                       case 3:                                                 \
 125                         *((__uint16_t *) __dest) =                            \
 126                           __STRING2_SMALL_GET16 (src, 0);                     \
 127                         *(__dest + 2) = '\0';                                 \
 128                         break;                                                \
 129                       case 4:                                                 \
 130                         *((__uint32_t *) __dest) =                            \
 131                           __STRING2_SMALL_GET32 (src, 0);                     \
 132                         break;                                                \
 133                       case 5:                                                 \
 134                         *((__uint32_t *) __dest) =                            \
 135                           __STRING2_SMALL_GET32 (src, 0);                     \
 136                         *(__dest + 4) = '\0';                                 \
 137                         break;                                                \
 138                       case 6:                                                 \
 139                         *((__uint32_t *) __dest) =                            \
 140                           __STRING2_SMALL_GET32 (src, 0);                     \
 141                         *((__uint16_t *) (__dest + 4)) =                      \
 142                           __STRING2_SMALL_GET16 (src, 4);                     \
 143                         break;                                                \
 144                       case 7:                                                 \
 145                         *((__uint32_t *) __dest) =                            \
 146                           __STRING2_SMALL_GET32 (src, 0);                     \
 147                         *((__uint16_t *) (__dest + 4)) =                      \
 148                           __STRING2_SMALL_GET16 (src, 4);                     \
 149                         *(__dest + 6) = '\0';                                 \
 150                         break;                                                \
 151                       case 8:                                                 \
 152                         *((__uint32_t *) __dest) =                            \
 153                           __STRING2_SMALL_GET32 (src, 0);                     \
 154                         *((__uint32_t *) (__dest + 4)) =                      \
 155                           __STRING2_SMALL_GET32 (src, 4);                     \
 156                         break;                                                \
 157                       }                                                       \
 158                     (char *) __dest; }))
 159 # else
 160 #  define __strcpy_small(dest, src, srclen) \
 161   (__extension__ ({ unsigned char *__dest = (unsigned char *) (dest);         \
 162                     switch (srclen)                                           \
 163                       {                                                       \
 164                       case 1:                                                 \
 165                         *__dest = '\0';                                       \
 166                         break;                                                \
 167                       case 2:                                                 \
 168                         *((__STRING2_COPY_ARR2 *) __dest) =                   \
 169                           ((__STRING2_COPY_ARR2)                              \
 170                            { { ((__const unsigned char *) (src))[0],          \
 171                                '\0' } });                                     \
 172                         break;                                                \
 173                       case 3:                                                 \
 174                         *((__STRING2_COPY_ARR3 *) __dest) =                   \
 175                           ((__STRING2_COPY_ARR3)                              \
 176                            { { ((__const unsigned char *) (src))[0],          \
 177                                ((__const unsigned char *) (src))[1],          \
 178                                '\0' } });                                     \
 179                         break;                                                \
 180                       case 4:                                                 \
 181                         *((__STRING2_COPY_ARR4 *) __dest) =                   \
 182                           ((__STRING2_COPY_ARR4)                              \
 183                            { { ((__const unsigned char *) (src))[0],          \
 184                                ((__const unsigned char *) (src))[1],          \
 185                                ((__const unsigned char *) (src))[2],          \
 186                                '\0' } });                                     \
 187                         break;                                                \
 188                       case 5:                                                 \
 189                         *((__STRING2_COPY_ARR5 *) __dest) =                   \
 190                           ((__STRING2_COPY_ARR5)                              \
 191                            { { ((__const unsigned char *) (src))[0],          \
 192                                ((__const unsigned char *) (src))[1],          \
 193                                ((__const unsigned char *) (src))[2],          \
 194                                ((__const unsigned char *) (src))[3],          \
 195                                '\0' } });                                     \
 196                         break;                                                \
 197                       case 6:                                                 \
 198                         *((__STRING2_COPY_ARR6 *) __dest) =                   \
 199                           ((__STRING2_COPY_ARR6)                              \
 200                            { { ((__const unsigned char *) (src))[0],          \
 201                                ((__const unsigned char *) (src))[1],          \
 202                                ((__const unsigned char *) (src))[2],          \
 203                                ((__const unsigned char *) (src))[3],          \
 204                                ((__const unsigned char *) (src))[4],          \
 205                                '\0' } });                                     \
 206                         break;                                                \
 207                       case 7:                                                 \
 208                         *((__STRING2_COPY_ARR7 *) __dest) =                   \
 209                           ((__STRING2_COPY_ARR7)                              \
 210                            { { ((__const unsigned char *) (src))[0],          \
 211                                ((__const unsigned char *) (src))[1],          \
 212                                ((__const unsigned char *) (src))[2],          \
 213                                ((__const unsigned char *) (src))[3],          \
 214                                ((__const unsigned char *) (src))[4],          \
 215                                ((__const unsigned char *) (src))[5],          \
 216                                '\0' } });                                     \
 217                         break;                                                \
 218                       case 8:                                                 \
 219                         *((__STRING2_COPY_ARR8 *) __dest) =                   \
 220                           ((__STRING2_COPY_ARR8)                              \
 221                            { { ((__const unsigned char *) (src))[0],          \
 222                                ((__const unsigned char *) (src))[1],          \
 223                                ((__const unsigned char *) (src))[2],          \
 224                                ((__const unsigned char *) (src))[3],          \
 225                                ((__const unsigned char *) (src))[4],          \
 226                                ((__const unsigned char *) (src))[5],          \
 227                                ((__const unsigned char *) (src))[6],          \
 228                                '\0' } });                                     \
 229                         break;                                                \
 230                     }                                                         \
 231                   (char *) __dest; }))
 232 # endif
 233 #endif
 234
 235
 236 /* Copy SRC to DEST, returning pointer to final NUL byte.  */
 237 #ifdef __USE_GNU
 238 # ifndef _HAVE_STRING_ARCH_stpcpy
 239 #  define __stpcpy(dest, src) \
 240   (__extension__ (__builtin_constant_p (src)                                  \
 241                   ? (__string2_1bptr_p (src) && strlen (src) + 1 <= 8         \
 242                      ? __stpcpy_small (dest, src, strlen (src) + 1)           \
 243                      : ((char *) __mempcpy (dest, src, strlen (src) + 1) - 1))\
 244                   : __stpcpy (dest, src)))
 245 /* In glibc we use this function frequently but for namespace reasons
 246    we have to use the name `__stpcpy'.  */
 247 #  define stpcpy(dest, src) __stpcpy (dest, src)
 248
 249 #  if _STRING_ARCH_unaligned
 250 #   define __stpcpy_small(dest, src, srclen) \
 251   (__extension__ ({ unsigned char *__dest = (unsigned char *) (dest);         \
 252                     switch (srclen)                                           \
 253                       {                                                       \
 254                       case 1:                                                 \
 255                         *__dest = '\0';                                       \
 256                         break;                                                \
 257                       case 2:                                                 \
 258                         *((__uint16_t *) __dest) =                            \
 259                           __STRING2_SMALL_GET16 (src, 0);                     \
 260                         ++__dest;                                             \
 261                         break;                                                \
 262                       case 3:                                                 \
 263                         *((__uint16_t *) __dest) =                            \
 264                           __STRING2_SMALL_GET16 (src, 0);                     \
 265                         __dest += sizeof (__uint16_t);                        \
 266                         *__dest = '\0';                                       \
 267                         break;                                                \
 268                       case 4:                                                 \
 269                         *((__uint32_t *) __dest) =                            \
 270                           __STRING2_SMALL_GET32 (src, 0);                     \
 271                         __dest += 3;                                          \
 272                         break;                                                \
 273                       case 5:                                                 \
 274                         *((__uint32_t *) __dest) =                            \
 275                           __STRING2_SMALL_GET32 (src, 0);                     \
 276                         __dest += sizeof (__uint32_t);                        \
 277                         *__dest = '\0';                                       \
 278                         break;                                                \
 279                       case 6:                                                 \
 280                         *((__uint32_t *) __dest) =                            \
 281                           __STRING2_SMALL_GET32 (src, 0);                     \
 282                         *((__uint16_t *) (__dest + 4)) =                      \
 283                           __STRING2_SMALL_GET16 (src, 4);                     \
 284                         __dest += 5;                                          \
 285                         break;                                                \
 286                       case 7:                                                 \
 287                         *((__uint32_t *) __dest) =                            \
 288                           __STRING2_SMALL_GET32 (src, 0);                     \
 289                         *((__uint16_t *) (__dest + 4)) =                      \
 290                           __STRING2_SMALL_GET16 (src, 4);                     \
 291                         __dest += 6;                                          \
 292                         *__dest = '\0';                                       \
 293                         break;                                                \
 294                       case 8:                                                 \
 295                         *((__uint32_t *) __dest) =                            \
 296                           __STRING2_SMALL_GET32 (src, 0);                     \
 297                         *((__uint32_t *) (__dest + 4)) =                      \
 298                           __STRING2_SMALL_GET32 (src, 4);                     \
 299                         __dest += 7;                                          \
 300                         break;                                                \
 301                       }                                                       \
 302                     (char *) __dest; }))
 303 #  else
 304 #   define __stpcpy_small(dest, src, srclen) \
 305   (__extension__ ({ unsigned char *__dest = (unsigned char *) (dest);         \
 306                     switch (srclen)                                           \
 307                       {                                                       \
 308                       case 1:                                                 \
 309                         *__dest = '\0';                                       \
 310                         break;                                                \
 311                       case 2:                                                 \
 312                         *((__STRING2_COPY_ARR2 *) __dest) =                   \
 313                           ((__STRING2_COPY_ARR2)                              \
 314                            { { ((__const unsigned char *) (src))[0],          \
 315                                '\0' } });                                     \
 316                         break;                                                \
 317                       case 3:                                                 \
 318                         *((__STRING2_COPY_ARR3 *) __dest) =                   \
 319                           ((__STRING2_COPY_ARR3)                              \
 320                            { { ((__const unsigned char *) (src))[0],          \
 321                                ((__const unsigned char *) (src))[1],          \
 322                                '\0' } });                                     \
 323                         break;                                                \
 324                       case 4:                                                 \
 325                         *((__STRING2_COPY_ARR4 *) __dest) =                   \
 326                           ((__STRING2_COPY_ARR4)                              \
 327                            { { ((__const unsigned char *) (src))[0],          \
 328                                ((__const unsigned char *) (src))[1],          \
 329                                ((__const unsigned char *) (src))[2],          \
 330                                '\0' } });                                     \
 331                         break;                                                \
 332                       case 5:                                                 \
 333                         *((__STRING2_COPY_ARR5 *) __dest) =                   \
 334                           ((__STRING2_COPY_ARR5)                              \
 335                            { { ((__const unsigned char *) (src))[0],          \
 336                                ((__const unsigned char *) (src))[1],          \
 337                                ((__const unsigned char *) (src))[2],          \
 338                                ((__const unsigned char *) (src))[3],          \
 339                                '\0' } });                                     \
 340                         break;                                                \
 341                       case 6:                                                 \
 342                         *((__STRING2_COPY_ARR6 *) __dest) =                   \
 343                           ((__STRING2_COPY_ARR6)                              \
 344                            { { ((__const unsigned char *) (src))[0],          \
 345                                ((__const unsigned char *) (src))[1],          \
 346                                ((__const unsigned char *) (src))[2],          \
 347                                ((__const unsigned char *) (src))[3],          \
 348                                ((__const unsigned char *) (src))[4],          \
 349                                '\0' } });                                     \
 350                         break;                                                \
 351                       case 7:                                                 \
 352                         *((__STRING2_COPY_ARR7 *) __dest) =                   \
 353                           ((__STRING2_COPY_ARR7)                              \
 354                            { { ((__const unsigned char *) (src))[0],          \
 355                                ((__const unsigned char *) (src))[1],          \
 356                                ((__const unsigned char *) (src))[2],          \
 357                                ((__const unsigned char *) (src))[3],          \
 358                                ((__const unsigned char *) (src))[4],          \
 359                                ((__const unsigned char *) (src))[5],          \
 360                                '\0' } });                                     \
 361                         break;                                                \
 362                       case 8:                                                 \
 363                         *((__STRING2_COPY_ARR8 *) __dest) =                   \
 364                           ((__STRING2_COPY_ARR8)                              \
 365                            { { ((__const unsigned char *) (src))[0],          \
 366                                ((__const unsigned char *) (src))[1],          \
 367                                ((__const unsigned char *) (src))[2],          \
 368                                ((__const unsigned char *) (src))[3],          \
 369                                ((__const unsigned char *) (src))[4],          \
 370                                ((__const unsigned char *) (src))[5],          \
 371                                ((__const unsigned char *) (src))[6],          \
 372                                '\0' } });                                     \
 373                         break;                                                \
 374                     }                                                         \
 375                   (char *) (__dest + ((srclen) - 1)); }))
 376 #  endif
 377 # endif
 378 #endif
 379
 380
 381 /* Copy no more than N characters of SRC to DEST.  */
 382 #ifndef _HAVE_STRING_ARCH_strncpy
 383 # if defined _HAVE_STRING_ARCH_memset && defined _HAVE_STRING_ARCH_mempcpy
 384 #  define strncpy(dest, src, n) \
 385   (__extension__ ({ char *__dest = (dest);                                    \
 386                     __builtin_constant_p (src) && __builtin_constant_p (n)    \
 387                     ? (strlen (src) + 1 >= ((size_t) (n))                     \
 388                        ? (char *) memcpy (__dest, src, n)                     \
 389                        : (memset (__mempcpy (__dest, src, strlen (src)),      \
 390                                   '\0', n - strlen (src)),                    \
 391                           __dest))                                            \
 392                     : strncpy (__dest, src, n); }))
 393 # else
 394 #  define strncpy(dest, src, n) \
 395   (__extension__ (__builtin_constant_p (src) && __builtin_constant_p (n)      \
 396                   ? (strlen (src) + 1 >= ((size_t) (n))                       \
 397                      ? (char *) memcpy (dest, src, n)                         \
 398                      : strncpy (dest, src, n))                                \
 399                   : strncpy (dest, src, n)))
 400 # endif
 401 #endif
 402
 403
 404 /* Append no more than N characters from SRC onto DEST.  */
 405 #ifndef _HAVE_STRING_ARCH_strncat
 406 # ifdef _HAVE_STRING_ARCH_strchr
 407 #  define strncat(dest, src, n) \
 408   (__extension__ ({ char *__dest = (dest);                                    \
 409                     __builtin_constant_p (src) && __builtin_constant_p (n)    \
 410                     ? (strlen (src) < ((size_t) (n))                          \
 411                        ? strcat (__dest, src)                                 \
 412                        : (memcpy (strchr (__dest, '\0'), src, n), __dest))    \
 413                     : strncat (dest, src, n); }))
 414 # else
 415 #  define strncat(dest, src, n) \
 416   (__extension__ (__builtin_constant_p (src) && __builtin_constant_p (n)      \
 417                   ? (strlen (src) < ((size_t) (n))                            \
 418                      ? strcat (dest, src)                                     \
 419                      : strncat (dest, src, n))                                \
 420                   : strncat (dest, src, n)))
 421 # endif
 422 #endif
 423
 424
 425 /* Compare characters of S1 and S2.  */
 426 #ifndef _HAVE_STRING_ARCH_strcmp
 427 # define strcmp(s1, s2) \
 428   (__extension__ (__builtin_constant_p (s1) && __builtin_constant_p (s2)      \
 429                   && (!__string2_1bptr_p (s1) || strlen (s1) >= 4)            \
 430                   && (!__string2_1bptr_p (s2) || strlen (s2) >= 4)            \
 431                   ? memcmp (s1, s2, (strlen (s1) < strlen (s2)                \
 432                                      ? strlen (s1) : strlen (s2)) + 1)        \
 433                   : (__builtin_constant_p (s1) && __string2_1bptr_p (s1)      \
 434                      && strlen (s1) < 4                                       \
 435                      ? (__builtin_constant_p (s2) && __string2_1bptr_p (s2)   \
 436                         ? __strcmp_cc (s1, s2, strlen (s1))                   \
 437                         : __strcmp_cg (s1, s2, strlen (s1)))                  \
 438                      : (__builtin_constant_p (s2) && __string2_1bptr_p (s2)   \
 439                         && strlen (s2) < 4                                    \
 440                         ? (__builtin_constant_p (s1) && __string2_1bptr_p (s1)\
 441                            ? __strcmp_cc (s1, s2, strlen (s2))                \
 442                            : __strcmp_gc (s1, s2, strlen (s2)))               \
 443                         : strcmp (s1, s2)))))
 444
 445 # define __strcmp_cc(s1, s2, l) \
 446   (__extension__ ({ register int __result =                                   \
 447                       (((__const unsigned char *) (s1))[0]                    \
 448                        - ((__const unsigned char *) (s2))[0]);                \
 449                     if (l > 0 && __result == 0)                               \
 450                       {                                                       \
 451                         __result = (((__const unsigned char *) (s1))[1]       \
 452                                     - ((__const unsigned char *) (s2))[1]);   \
 453                         if (l > 1 && __result == 0)                           \
 454                           {                                                   \
 455                             __result =                                        \
 456                               (((__const unsigned char *) (s1))[2]            \
 457                                - ((__const unsigned char *) (s2))[2]);        \
 458                             if (l > 2 && __result == 0)                       \
 459                               __result =                                      \
 460                                 (((__const unsigned char *) (s1))[3]          \
 461                                  - ((__const unsigned char *) (s2))[3]);      \
 462                           }                                                   \
 463                       }                                                       \
 464                     __result; }))
 465
 466 # define __strcmp_cg(s1, s2, l1) \
 467   (__extension__ ({ __const unsigned char *__s2 =                             \
 468                       (__const unsigned char *) (s2);                         \
 469                     register int __result =                                   \
 470                       (((__const unsigned char *) (s1))[0] - __s2[0]);        \
 471                     if (l1 > 0 && __result == 0)                              \
 472                       {                                                       \
 473                         __result = (((__const unsigned char *) (s1))[1]       \
 474                                     - __s2[1]);                               \
 475                         if (l1 > 1 && __result == 0)                          \
 476                           {                                                   \
 477                             __result = (((__const unsigned char *) (s1))[2]   \
 478                                         - __s2[2]);                           \
 479                             if (l1 > 2 && __result == 0)                      \
 480                               __result = (((__const unsigned char *) (s1))[3] \
 481                                           - __s2[3]);                         \
 482                           }                                                   \
 483                       }                                                       \
 484                     __result; }))
 485
 486 # define __strcmp_gc(s1, s2, l2) \
 487   (__extension__ ({ __const unsigned char *__s1 =                             \
 488                       (__const unsigned char *) (s1);                         \
 489                     register int __result =                                   \
 490                       __s1[0] - ((__const unsigned char *) (s2))[0];          \
 491                     if (l2 > 0 && __result == 0)                              \
 492                       {                                                       \
 493                         __result = (__s1[1]                                   \
 494                                     - ((__const unsigned char *) (s2))[1]);   \
 495                         if (l2 > 1 && __result == 0)                          \
 496                           {                                                   \
 497                             __result =                                        \
 498                               (__s1[2] - ((__const unsigned char *) (s2))[2]);\
 499                             if (l2 > 2 && __result == 0)                      \
 500                               __result =                                      \
 501                                 (__s1[3]                                      \
 502                                  - ((__const unsigned char *)(s2))[3]);       \
 503                           }                                                   \
 504                       }                                                       \
 505                     __result; }))
 506 #endif
 507
 508
 509 /* Compare N characters of S1 and S2.  */
 510 #ifndef _HAVE_STRING_ARCH_strncmp
 511 # define strncmp(s1, s2, n) \
 512   (__extension__ (__builtin_constant_p (s1) && strlen (s1) < ((size_t) (n))   \
 513                   ? strcmp (s1, s2)                                           \
 514                   : (__builtin_constant_p (s2) && strlen (s2) < ((size_t) (n))\
 515                      ? strcmp (s1, s2)                                        \
 516                      : strncmp (s1, s2, n))))
 517 #endif
 518
 519
 520 /* Return the length of the initial segment of S which
 521    consists entirely of characters not in REJECT.  */
 522 #ifndef _HAVE_STRING_ARCH_strcspn
 523 # define strcspn(s, reject) \
 524   (__extension__ (__builtin_constant_p (reject) && __string2_1bptr_p (reject) \
 525                   ? (((__const unsigned char *) (reject))[0] == '\0'          \
 526                      ? strlen (s)                                             \
 527                      : (((__const unsigned char *) (reject))[1] == '\0'       \
 528                         ? __strcspn_c1 (s, ((__const char *) (reject))[0])    \
 529                         : (((__const unsigned char *) (reject))[2] == '\0'    \
 530                            ? __strcspn_c2 (s, ((__const char *) (reject))[0], \
 531                                            ((__const char *) (reject))[1])    \
 532                            : (((__const unsigned char *) (reject))[3] == '\0' \
 533                               ? __strcspn_c3 (s,                              \
 534                                               ((__const char *) (reject))[0], \
 535                                               ((__const char *) (reject))[1], \
 536                                               ((__const char *) (reject))[2]) \
 537                               : strcspn (s, reject)))))                       \
 538                   : strcspn (s, reject)))
 539
 540 __STRING_INLINE size_t __strcspn_c1 (__const char *__s, char __reject);
 541 __STRING_INLINE size_t
 542 __strcspn_c1 (__const char *__s, char __reject)
 543 {
 544   register size_t __result = 0;
 545   while (__s[__result] != '\0' && __s[__result] != __reject)
 546     ++__result;
 547   return __result;
 548 }
 549
 550 __STRING_INLINE size_t __strcspn_c2 (__const char *__s, char __reject1,
 551                                      char __reject2);
 552 __STRING_INLINE size_t
 553 __strcspn_c2 (__const char *__s, char __reject1, char __reject2)
 554 {
 555   register size_t __result = 0;
 556   while (__s[__result] != '\0' && __s[__result] != __reject1
 557          && __s[__result] != __reject2)
 558     ++__result;
 559   return __result;
 560 }
 561
 562 __STRING_INLINE size_t __strcspn_c3 (__const char *__s, char __reject1,
 563                                      char __reject2, char __reject3);
 564 __STRING_INLINE size_t
 565 __strcspn_c3 (__const char *__s, char __reject1, char __reject2,
 566               char __reject3)
 567 {
 568   register size_t __result = 0;
 569   while (__s[__result] != '\0' && __s[__result] != __reject1
 570          && __s[__result] != __reject2 && __s[__result] != __reject3)
 571     ++__result;
 572   return __result;
 573 }
 574 #endif
 575
 576
 577 /* Return the length of the initial segment of S which
 578    consists entirely of characters in ACCEPT.  */
 579 #ifndef _HAVE_STRING_ARCH_strspn
 580 # define strspn(s, accept) \
 581   (__extension__ (__builtin_constant_p (accept) && __string2_1bptr_p (accept) \
 582                   ? (((__const unsigned char *) (accept))[0] == '\0'          \
 583                      ? 0                                                      \
 584                      : (((__const unsigned char *) (accept))[1] == '\0'       \
 585                         ? __strspn_c1 (s, ((__const char *) (accept))[0])     \
 586                         : (((__const unsigned char *) (accept))[2] == '\0'    \
 587                            ? __strspn_c2 (s, ((__const char *) (accept))[0],  \
 588                                           ((__const char *) (accept))[1])     \
 589                            : (((__const unsigned char *) (accept))[3] == '\0' \
 590                               ? __strspn_c3 (s,                               \
 591                                              ((__const char *) (accept))[0],  \
 592                                              ((__const char *) (accept))[1],  \
 593                                              ((__const char *) (accept))[2])  \
 594                               : strspn (s, accept)))))                        \
 595                   : strspn (s, accept)))
 596
 597 __STRING_INLINE size_t __strspn_c1 (__const char *__s, char __accept);
 598 __STRING_INLINE size_t
 599 __strspn_c1 (__const char *__s, char __accept)
 600 {
 601   register size_t __result = 0;
 602   /* Please note that __accept never can be '\0'.  */
 603   while (__s[__result] == __accept)
 604     ++__result;
 605   return __result;
 606 }
 607
 608 __STRING_INLINE size_t __strspn_c2 (__const char *__s, char __accept1,
 609                                     char __accept2);
 610 __STRING_INLINE size_t
 611 __strspn_c2 (__const char *__s, char __accept1, char __accept2)
 612 {
 613   register size_t __result = 0;
 614   /* Please note that __accept1 and __accept2 never can be '\0'.  */
 615   while (__s[__result] == __accept1 || __s[__result] == __accept2)
 616     ++__result;
 617   return __result;
 618 }
 619
 620 __STRING_INLINE size_t __strspn_c3 (__const char *__s, char __accept1,
 621                                     char __accept2, char __accept3);
 622 __STRING_INLINE size_t
 623 __strspn_c3 (__const char *__s, char __accept1, char __accept2, char __accept3)
 624 {
 625   register size_t __result = 0;
 626   /* Please note that __accept1 to __accept3 never can be '\0'.  */
 627   while (__s[__result] == __accept1 || __s[__result] == __accept2
 628          || __s[__result] == __accept3)
 629     ++__result;
 630   return __result;
 631 }
 632 #endif
 633
 634
 635 /* Find the first occurrence in S of any character in ACCEPT.  */
 636 #ifndef _HAVE_STRING_ARCH_strpbrk
 637 # define strpbrk(s, accept) \
 638   (__extension__ (__builtin_constant_p (accept) && __string2_1bptr_p (accept) \
 639                   ? (((__const unsigned char  *) (accept))[0] == '\0'         \
 640                      ? NULL                                                   \
 641                      : (((__const unsigned char *) (accept))[1] == '\0'       \
 642                         ? strchr (s, ((__const unsigned char *) (accept))[0]) \
 643                         : (((__const unsigned char *) (accept))[2] == '\0'    \
 644                            ? __strpbrk_c2 (s, ((__const char *) (accept))[0], \
 645                                            ((__const char *) (accept))[1])    \
 646                            : (((__const unsigned char *) (accept))[3] == '\0' \
 647                               ? __strpbrk_c3 (s,                              \
 648                                               ((__const char *) (accept))[0], \
 649                                               ((__const char *) (accept))[1], \
 650                                               ((__const char *) (accept))[2]) \
 651                               : strpbrk (s, accept)))))                       \
 652                   : strpbrk (s, accept)))
 653
 654 __STRING_INLINE char *__strpbrk_c2 (__const char *__s, char __accept1,
 655                                      char __accept2);
 656 __STRING_INLINE char *
 657 __strpbrk_c2 (__const char *__s, char __accept1, char __accept2)
 658 {
 659   /* Please note that __accept1 and __accept2 never can be '\0'.  */
 660   while (*__s != '\0' && *__s != __accept1 && *__s != __accept2)
 661     ++__s;
 662   return *__s == '\0' ? NULL : (char *) __s;
 663 }
 664
 665 __STRING_INLINE char *__strpbrk_c3 (__const char *__s, char __accept1,
 666                                      char __accept2, char __accept3);
 667 __STRING_INLINE char *
 668 __strpbrk_c3 (__const char *__s, char __accept1, char __accept2,
 669               char __accept3)
 670 {
 671   /* Please note that __accept1 to __accept3 never can be '\0'.  */
 672   while (*__s != '\0' && *__s != __accept1 && *__s != __accept2
 673          && *__s != __accept3)
 674     ++__s;
 675   return *__s == '\0' ? NULL : (char *) __s;
 676 }
 677 #endif
 678
 679
 680 /* Find the first occurrence of NEEDLE in HAYSTACK.  */
 681 #ifndef _HAVE_STRING_ARCH_strstr
 682 # define strstr(haystack, needle) \
 683   (__extension__ (__builtin_constant_p (needle) && __string2_1bptr_p (needle) \
 684                   ? (((__const unsigned char *) (needle))[0] == '\0'          \
 685                      ? (char *) (haystack)                                    \
 686                      : (((__const unsigned char *) (needle))[1] == '\0'       \
 687                         ? strchr (haystack,                                   \
 688                                   ((__const unsigned char *) (needle))[0])    \
 689                         : strstr (haystack, needle)))                         \
 690                   : strstr (haystack, needle)))
 691 #endif
 692
 693
 694 #ifdef __USE_GNU
 695 # ifndef _HAVE_STRING_ARCH_strnlen
 696 __STRING_INLINE size_t strnlen (__const char *__string, size_t __maxlen);
 697 __STRING_INLINE size_t
 698 strnlen (__const char *__string, size_t __maxlen)
 699 {
 700   __const char *__end = (__const char *) memchr (__string, '\0', __maxlen);
 701   return __end ? __end - __string : __maxlen;
 702 }
 703 # endif
 704 #endif
 705
 706
 707 #ifndef _HAVE_STRING_ARCH_strtok_r
 708 # define __strtok_r(s, sep, nextp) \
 709   (__extension__ (__builtin_constant_p (sep) && __string2_1bptr_p (sep)       \
 710                   ? (((__const unsigned char *) (sep))[0] != '\0'             \
 711                      && ((__const unsigned char *) (sep))[1] == '\0'          \
 712                      ? __strtok_r_1c (s, ((__const char *) (sep))[0], nextp)  \
 713                      : strtok_r (s, sep, nextp))                              \
 714                   : strtok_r (s, sep, nextp)))
 715
 716 __STRING_INLINE char *__strtok_r_1c (char *__s, char __sep, char **__nextp);
 717 __STRING_INLINE char *
 718 __strtok_r_1c (char *__s, char __sep, char **__nextp)
 719 {
 720   char *__result;
 721   if (__s == NULL)
 722     __s = *__nextp;
 723   while (*__s == __sep)
 724     ++__s;
 725   if (*__s == '\0')
 726     __result = NULL;
 727   else
 728     {
 729       __result = __s;
 730       while (*__s != '\0' && *__s != __sep)
 731         ++__s;
 732       if (*__s == '\0')
 733         *__nextp = __s;
 734       else
 735         {
 736           *__s = '\0';
 737           *__nextp = __s + 1;
 738         }
 739     }
 740   return __result;
 741 }
 742 # if defined __USE_POSIX || defined __USE_MISC
 743 #  define strtok_r(s, sep, nextp) __strtok_r (s, sep, nextp)
 744 # endif
 745 #endif
 746
 747
 748 #ifndef _HAVE_STRING_ARCH_strsep
 749
 750 # define __strsep(s, reject) \
 751   (__extension__ (__builtin_constant_p (reject) && __string2_1bptr_p (reject) \
 752                   && ((__const unsigned char *) (reject))[0] != '\0'          \
 753                   ? (((__const unsigned char *) (reject))[1] == '\0'          \
 754                      ? __strsep_1c (s,                                        \
 755                                     ((__const char *) (reject))[0])           \
 756                      : (((__const unsigned char *) (reject))[2] == '\0'       \
 757                         ? __strsep_2c (s, ((__const char *) (reject))[0],     \
 758                                        ((__const char *) (reject))[1])        \
 759                         : (((__const unsigned char *) (reject))[3] == '\0'    \
 760                            ? __strsep_3c (s, ((__const char *) (reject))[0],  \
 761                                           ((__const char *) (reject))[1],     \
 762                                           ((__const char *) (reject))[2])     \
 763                            : __strsep_g (s, reject))))                        \
 764                   : __strsep_g (s, reject)))
 765
 766 __STRING_INLINE char *__strsep_1c (char **__s, char __reject);
 767 __STRING_INLINE char *
 768 __strsep_1c (char **__s, char __reject)
 769 {
 770   register char *__retval = *__s;
 771   if (__retval == NULL)
 772     return *__s = NULL;
 773   if (*__retval == __reject)
 774     *(*__s)++ = '\0';
 775   else
 776     if ((*__s = strchr (__retval, __reject)) != NULL)
 777       *(*__s)++ = '\0';
 778     else
 779       *__s = NULL;
 780   return __retval;
 781 }
 782
 783 __STRING_INLINE char *__strsep_2c (char **__s, char __reject1, char __reject2);
 784 __STRING_INLINE char *
 785 __strsep_2c (char **__s, char __reject1, char __reject2)
 786 {
 787   register char *__retval = *__s;
 788   if (__retval == NULL)
 789     return *__s = NULL;
 790   if (*__retval == __reject1 || *__retval == __reject2)
 791     *(*__s)++ = '\0';
 792   else
 793     {
 794       register char *__cp = __retval;
 795       while (*__cp != '\0' && *__cp != __reject1 && *__cp != __reject2)
 796         ++__cp;
 797       if (*__cp != '\0')
 798         {
 799           *__s = __cp;
 800           *(*__s)++ = '\0';
 801         }
 802       else
 803         *__s = NULL;
 804     }
 805   return __retval;
 806 }
 807
 808 __STRING_INLINE char *__strsep_3c (char **__s, char __reject1, char __reject2,
 809                                    char __reject3);
 810 __STRING_INLINE char *
 811 __strsep_3c (char **__s, char __reject1, char __reject2, char __reject3)
 812 {
 813   register char *__retval = *__s;
 814   if (__retval == NULL)
 815     return *__s = NULL;
 816   if (*__retval == __reject1 || *__retval == __reject2
 817       || *__retval == __reject3)
 818     *(*__s)++ = '\0';
 819   else
 820     {
 821       register char *__cp = __retval;
 822       while (*__cp != '\0' && *__cp != __reject1 && *__cp != __reject2
 823              && *__cp != __reject3)
 824         ++__cp;
 825       if (*__cp != '\0')
 826         {
 827           *__s = __cp;
 828           *(*__s)++ = '\0';
 829         }
 830       else
 831         *__s = NULL;
 832     }
 833   return __retval;
 834 }
 835
 836 __STRING_INLINE char *__strsep_g (char **__s, __const char *__reject);
 837 __STRING_INLINE char *
 838 __strsep_g (char **__s, __const char *__reject)
 839 {
 840   register char *__retval = *__s;
 841   if (__retval == NULL || *__retval == '\0')
 842     return NULL;
 843   if ((*__s = strpbrk (__retval, __reject)) != NULL)
 844     *(*__s)++ = '\0';
 845   return __retval;
 846 }
 847 # ifdef __USE_BSD
 848 #  define strsep(s, reject) __strsep (s, reject)
 849 # endif
 850 #endif
 851
 852
 853 #if !defined _HAVE_STRING_ARCH_strdup && !defined __STRICT_ANSI__
 854
 855 /* We need the memory allocation functions.  Including this header is
 856    not allowed. */
 857 # include <stdlib.h>
 858
 859 # define __strdup(s) \
 860   (__extension__ (__builtin_constant_p (s) && __string2_1bptr_p (s)
 861                   ? (((__const unsigned char *) (s))[0] == '\0'
 862                      ? return (char *) calloc (1, 1);
 863                      : ({ size_t len = strlen (s) + 1;
 864                           char *retval = (char *) malloc (len);
 865                           if (retval != NULL)
 866                             retval = (char *) memcpy (retval, s, len);
 867                           retval; }))
 868                   : strdup (s)))
 869
 870 # if defined __USE_SVID || defined __USE_BSD || defined __USE_XOPEN_EXTENDED
 871 #  define strdup(s) __strdup (s)
 872 # endif
 873 #endif
 874
 875
 876 #undef __STRING_INLINE
 877
 878 #endif /* No string inlines.  */