/* Machine-independant string function optimizations. Copyright (C) 1997 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper , 1997. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with the GNU C Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #ifndef _STRING_H # error "Never use directly; include instead." #endif #ifndef __NO_STRING_INLINES /* Unlike the definitions in the header the definitions contained here are not optimizing down to assembler level. These optimizations are not always a good idea since this means the code size increases a lot. Instead the definitions here optimize some functions in a way which does not dramatically increase the code size and which does not use assembler. The main trick is to use GNU CC's `__builtin_constant_p' function. Every function XXX which has a defined version in must be accompanied by a symbol _HAVE_STRING_ARCH_XXX to make sure we don't get redefinitions. We must use here macros instead of inline functions since the trick won't work with the later. */ #ifdef __cplusplus # define __STRING_INLINE inline #else # define __STRING_INLINE extern __inline #endif #if _STRING_ARCH_unaligned /* If we can do unaligned memory accesses we must know the endianess. */ # include # include # if __BYTE_ORDER == __LITTLE_ENDIAN # define __STRING2_SMALL_GET16(src, idx) \ (((__const unsigned char *) (src))[idx + 1] << 8 \ | ((__const unsigned char *) (src))[idx]) # define __STRING2_SMALL_GET32(src, idx) \ (((((__const unsigned char *) (src))[idx + 3] << 8 \ | ((__const char *) (src))[idx + 2]) << 8 \ | ((__const unsigned char *) (src))[idx + 1]) << 8 \ | ((__const unsigned char *) (src))[idx]) # else # define __STRING2_SMALL_GET16(src, idx) \ (((__const unsigned char *) (src))[idx] << 8 \ | ((__const unsigned char *) (src))[idx + 1]) # define __STRING2_SMALL_GET32(src, idx) \ (((((__const unsigned char *) (src))[idx] << 8 \ | ((__const unsigned char *) (src))[idx + 1]) << 8 \ | ((__const unsigned char *) (src))[idx + 2]) << 8 \ | ((__const unsigned char *) (src))[idx + 3]) # endif #else /* These are a few types we need for the optimizations if we cannot use unaligned memory accesses. */ # define __STRING2_COPY_TYPE(N) \ typedef struct { char __arr[N]; } \ __STRING2_COPY_ARR##N __attribute__ ((packed)) __STRING2_COPY_TYPE (2); __STRING2_COPY_TYPE (3); __STRING2_COPY_TYPE (4); __STRING2_COPY_TYPE (5); __STRING2_COPY_TYPE (6); __STRING2_COPY_TYPE (7); __STRING2_COPY_TYPE (8); # undef __STRING2_COPY_TYPE #endif /* Dereferencing a pointer arg to run sizeof on it fails for the void pointer case, so we use this instead. */ #define __string2_1bptr_p(x) (((size_t) ((x) + 1) - (size_t) (x)) == 1) /* Set N bytes of S to C. */ #ifndef _HAVE_STRING_ARCH_memset # define memset(s, c, n) \ (__extension__ (__builtin_constant_p (c) && (c) == '\0' \ ? ({ void *__s = (s); __bzero (__s, n); __s; }) \ : memset (s, c, n))) #endif /* Copy SRC to DEST. */ #ifndef _HAVE_STRING_ARCH_strcpy # define strcpy(dest, src) \ (__extension__ (__builtin_constant_p (src) \ ? (__string2_1bptr_p (src) && strlen (src) + 1 <= 8 \ ? __strcpy_small (dest, src, strlen (src) + 1) \ : (char *) memcpy (dest, src, strlen (src) + 1)) \ : strcpy (dest, src))) # if _STRING_ARCH_unaligned # define __strcpy_small(dest, src, srclen) \ (__extension__ ({ unsigned char *__dest = (unsigned char *) (dest); \ switch (srclen) \ { \ case 1: \ *__dest = '\0'; \ break; \ case 2: \ *((__uint16_t *) __dest) = \ __STRING2_SMALL_GET16 (src, 0); \ break; \ case 3: \ *((__uint16_t *) __dest) = \ __STRING2_SMALL_GET16 (src, 0); \ *(__dest + 2) = '\0'; \ break; \ case 4: \ *((__uint32_t *) __dest) = \ __STRING2_SMALL_GET32 (src, 0); \ break; \ case 5: \ *((__uint32_t *) __dest) = \ __STRING2_SMALL_GET32 (src, 0); \ *(__dest + 4) = '\0'; \ break; \ case 6: \ *((__uint32_t *) __dest) = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint16_t *) (__dest + 4)) = \ __STRING2_SMALL_GET16 (src, 4); \ break; \ case 7: \ *((__uint32_t *) __dest) = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint16_t *) (__dest + 4)) = \ __STRING2_SMALL_GET16 (src, 4); \ *(__dest + 6) = '\0'; \ break; \ case 8: \ *((__uint32_t *) __dest) = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint32_t *) (__dest + 4)) = \ __STRING2_SMALL_GET32 (src, 4); \ break; \ } \ (char *) __dest; })) # else # define __strcpy_small(dest, src, srclen) \ (__extension__ ({ unsigned char *__dest = (unsigned char *) (dest); \ switch (srclen) \ { \ case 1: \ *__dest = '\0'; \ break; \ case 2: \ *((__STRING2_COPY_ARR2 *) __dest) = \ ((__STRING2_COPY_ARR2) \ { { ((__const unsigned char *) (src))[0], \ '\0' } }); \ break; \ case 3: \ *((__STRING2_COPY_ARR3 *) __dest) = \ ((__STRING2_COPY_ARR3) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ '\0' } }); \ break; \ case 4: \ *((__STRING2_COPY_ARR4 *) __dest) = \ ((__STRING2_COPY_ARR4) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ ((__const unsigned char *) (src))[2], \ '\0' } }); \ break; \ case 5: \ *((__STRING2_COPY_ARR5 *) __dest) = \ ((__STRING2_COPY_ARR5) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ ((__const unsigned char *) (src))[2], \ ((__const unsigned char *) (src))[3], \ '\0' } }); \ break; \ case 6: \ *((__STRING2_COPY_ARR6 *) __dest) = \ ((__STRING2_COPY_ARR6) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ ((__const unsigned char *) (src))[2], \ ((__const unsigned char *) (src))[3], \ ((__const unsigned char *) (src))[4], \ '\0' } }); \ break; \ case 7: \ *((__STRING2_COPY_ARR7 *) __dest) = \ ((__STRING2_COPY_ARR7) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ ((__const unsigned char *) (src))[2], \ ((__const unsigned char *) (src))[3], \ ((__const unsigned char *) (src))[4], \ ((__const unsigned char *) (src))[5], \ '\0' } }); \ break; \ case 8: \ *((__STRING2_COPY_ARR8 *) __dest) = \ ((__STRING2_COPY_ARR8) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ ((__const unsigned char *) (src))[2], \ ((__const unsigned char *) (src))[3], \ ((__const unsigned char *) (src))[4], \ ((__const unsigned char *) (src))[5], \ ((__const unsigned char *) (src))[6], \ '\0' } }); \ break; \ } \ (char *) __dest; })) # endif #endif /* Copy SRC to DEST, returning pointer to final NUL byte. */ #ifdef __USE_GNU # ifndef _HAVE_STRING_ARCH_stpcpy # define __stpcpy(dest, src) \ (__extension__ (__builtin_constant_p (src) \ ? (__string2_1bptr_p (src) && strlen (src) + 1 <= 8 \ ? __stpcpy_small (dest, src, strlen (src) + 1) \ : ((char *) __mempcpy (dest, src, strlen (src) + 1) - 1))\ : __stpcpy (dest, src))) /* In glibc we use this function frequently but for namespace reasons we have to use the name `__stpcpy'. */ # define stpcpy(dest, src) __stpcpy (dest, src) # if _STRING_ARCH_unaligned # define __stpcpy_small(dest, src, srclen) \ (__extension__ ({ unsigned char *__dest = (unsigned char *) (dest); \ switch (srclen) \ { \ case 1: \ *__dest = '\0'; \ break; \ case 2: \ *((__uint16_t *) __dest) = \ __STRING2_SMALL_GET16 (src, 0); \ ++__dest; \ break; \ case 3: \ *((__uint16_t *) __dest) = \ __STRING2_SMALL_GET16 (src, 0); \ __dest += sizeof (__uint16_t); \ *__dest = '\0'; \ break; \ case 4: \ *((__uint32_t *) __dest) = \ __STRING2_SMALL_GET32 (src, 0); \ __dest += 3; \ break; \ case 5: \ *((__uint32_t *) __dest) = \ __STRING2_SMALL_GET32 (src, 0); \ __dest += sizeof (__uint32_t); \ *__dest = '\0'; \ break; \ case 6: \ *((__uint32_t *) __dest) = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint16_t *) (__dest + 4)) = \ __STRING2_SMALL_GET16 (src, 4); \ __dest += 5; \ break; \ case 7: \ *((__uint32_t *) __dest) = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint16_t *) (__dest + 4)) = \ __STRING2_SMALL_GET16 (src, 4); \ __dest += 6; \ *__dest = '\0'; \ break; \ case 8: \ *((__uint32_t *) __dest) = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint32_t *) (__dest + 4)) = \ __STRING2_SMALL_GET32 (src, 4); \ __dest += 7; \ break; \ } \ (char *) __dest; })) # else # define __stpcpy_small(dest, src, srclen) \ (__extension__ ({ unsigned char *__dest = (unsigned char *) (dest); \ switch (srclen) \ { \ case 1: \ *__dest = '\0'; \ break; \ case 2: \ *((__STRING2_COPY_ARR2 *) __dest) = \ ((__STRING2_COPY_ARR2) \ { { ((__const unsigned char *) (src))[0], \ '\0' } }); \ break; \ case 3: \ *((__STRING2_COPY_ARR3 *) __dest) = \ ((__STRING2_COPY_ARR3) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ '\0' } }); \ break; \ case 4: \ *((__STRING2_COPY_ARR4 *) __dest) = \ ((__STRING2_COPY_ARR4) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ ((__const unsigned char *) (src))[2], \ '\0' } }); \ break; \ case 5: \ *((__STRING2_COPY_ARR5 *) __dest) = \ ((__STRING2_COPY_ARR5) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ ((__const unsigned char *) (src))[2], \ ((__const unsigned char *) (src))[3], \ '\0' } }); \ break; \ case 6: \ *((__STRING2_COPY_ARR6 *) __dest) = \ ((__STRING2_COPY_ARR6) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ ((__const unsigned char *) (src))[2], \ ((__const unsigned char *) (src))[3], \ ((__const unsigned char *) (src))[4], \ '\0' } }); \ break; \ case 7: \ *((__STRING2_COPY_ARR7 *) __dest) = \ ((__STRING2_COPY_ARR7) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ ((__const unsigned char *) (src))[2], \ ((__const unsigned char *) (src))[3], \ ((__const unsigned char *) (src))[4], \ ((__const unsigned char *) (src))[5], \ '\0' } }); \ break; \ case 8: \ *((__STRING2_COPY_ARR8 *) __dest) = \ ((__STRING2_COPY_ARR8) \ { { ((__const unsigned char *) (src))[0], \ ((__const unsigned char *) (src))[1], \ ((__const unsigned char *) (src))[2], \ ((__const unsigned char *) (src))[3], \ ((__const unsigned char *) (src))[4], \ ((__const unsigned char *) (src))[5], \ ((__const unsigned char *) (src))[6], \ '\0' } }); \ break; \ } \ (char *) (__dest + ((srclen) - 1)); })) # endif # endif #endif /* Copy no more than N characters of SRC to DEST. */ #ifndef _HAVE_STRING_ARCH_strncpy # if defined _HAVE_STRING_ARCH_memset && defined _HAVE_STRING_ARCH_mempcpy # define strncpy(dest, src, n) \ (__extension__ ({ char *__dest = (dest); \ __builtin_constant_p (src) && __builtin_constant_p (n) \ ? (strlen (src) + 1 >= ((size_t) (n)) \ ? (char *) memcpy (__dest, src, n) \ : (memset (__mempcpy (__dest, src, strlen (src)), \ '\0', n - strlen (src)), \ __dest)) \ : strncpy (__dest, src, n); })) # else # define strncpy(dest, src, n) \ (__extension__ (__builtin_constant_p (src) && __builtin_constant_p (n) \ ? (strlen (src) + 1 >= ((size_t) (n)) \ ? (char *) memcpy (dest, src, n) \ : strncpy (dest, src, n)) \ : strncpy (dest, src, n))) # endif #endif /* Append no more than N characters from SRC onto DEST. */ #ifndef _HAVE_STRING_ARCH_strncat # ifdef _HAVE_STRING_ARCH_strchr # define strncat(dest, src, n) \ (__extension__ ({ char *__dest = (dest); \ __builtin_constant_p (src) && __builtin_constant_p (n) \ ? (strlen (src) < ((size_t) (n)) \ ? strcat (__dest, src) \ : (memcpy (strchr (__dest, '\0'), src, n), __dest)) \ : strncat (dest, src, n); })) # else # define strncat(dest, src, n) \ (__extension__ (__builtin_constant_p (src) && __builtin_constant_p (n) \ ? (strlen (src) < ((size_t) (n)) \ ? strcat (dest, src) \ : strncat (dest, src, n)) \ : strncat (dest, src, n))) # endif #endif /* Compare characters of S1 and S2. */ #ifndef _HAVE_STRING_ARCH_strcmp # define strcmp(s1, s2) \ (__extension__ (__builtin_constant_p (s1) && __builtin_constant_p (s2) \ && (!__string2_1bptr_p (s1) || strlen (s1) >= 4) \ && (!__string2_1bptr_p (s2) || strlen (s2) >= 4) \ ? memcmp (s1, s2, (strlen (s1) < strlen (s2) \ ? strlen (s1) : strlen (s2)) + 1) \ : (__builtin_constant_p (s1) && __string2_1bptr_p (s1) \ && __string2_1bptr_p (s2) && strlen (s1) < 4 \ ? (__builtin_constant_p (s2) \ ? __strcmp_cc (s1, s2, strlen (s1)) \ : __strcmp_cg (s1, s2, strlen (s1))) \ : (__builtin_constant_p (s2) && __string2_1bptr_p (s1) \ && __string2_1bptr_p (s2) && strlen (s2) < 4 \ ? (__builtin_constant_p (s1) \ ? __strcmp_cc (s1, s2, strlen (s2)) \ : __strcmp_gc (s1, s2, strlen (s2))) \ : strcmp (s1, s2))))) # define __strcmp_cc(s1, s2, l) \ (__extension__ ({ register int __result = \ (((__const unsigned char *) (s1))[0] \ - ((__const unsigned char *) (s2))[0]); \ if (l > 0 && __result == 0) \ { \ __result = (((__const unsigned char *) (s1))[1] \ - ((__const unsigned char *) (s2))[1]); \ if (l > 1 && __result == 0) \ { \ __result = \ (((__const unsigned char *) (s1))[2] \ - ((__const unsigned char *) (s2))[2]); \ if (l > 2 && __result == 0) \ __result = \ (((__const unsigned char *) (s1))[3] \ - ((__const unsigned char *) (s2))[3]); \ } \ } \ __result; })) # define __strcmp_cg(s1, s2, l1) \ (__extension__ ({ __const unsigned char *__s2 = \ (__const unsigned char *) (s2); \ register int __result = \ (((__const unsigned char *) (s1))[0] - __s2[0]); \ if (l1 > 0 && __result == 0) \ { \ __result = (((__const unsigned char *) (s1))[1] \ - __s2[1]); \ if (l1 > 1 && __result == 0) \ { \ __result = (((__const unsigned char *) (s1))[2] \ - __s2[2]); \ if (l1 > 2 && __result == 0) \ __result = (((__const unsigned char *) (s1))[3] \ - __s2[3]); \ } \ } \ __result; })) # define __strcmp_gc(s1, s2, l2) \ (__extension__ ({ __const unsigned char *__s1 = \ (__const unsigned char *) (s1); \ register int __result = \ __s1[0] - ((__const unsigned char *) (s2))[0]; \ if (l2 > 0 && __result == 0) \ { \ __result = (__s1[1] \ - ((__const unsigned char *) (s2))[1]); \ if (l2 > 1 && __result == 0) \ { \ __result = \ (__s1[2] - ((__const unsigned char *) (s2))[2]);\ if (l2 > 2 && __result == 0) \ __result = \ (__s1[3] \ - ((__const unsigned char *)(s2))[3]); \ } \ } \ __result; })) #endif /* Compare N characters of S1 and S2. */ #ifndef _HAVE_STRING_ARCH_strncmp # define strncmp(s1, s2, n) \ (__extension__ (__builtin_constant_p (s1) && strlen (s1) < ((size_t) (n)) \ ? strcmp (s1, s2) \ : (__builtin_constant_p (s2) && strlen (s2) < ((size_t) (n))\ ? strcmp (s1, s2) \ : strncmp (s1, s2, n)))) #endif /* Return the length of the initial segment of S which consists entirely of characters not in REJECT. */ #ifndef _HAVE_STRING_ARCH_strcspn # define strcspn(s, reject) \ (__extension__ (__builtin_constant_p (reject) && __string2_1bptr_p (reject) \ ? (((__const unsigned char *) (reject))[0] == '\0' \ ? strlen (s) \ : (((__const unsigned char *) (reject))[1] == '\0' \ ? __strcspn_c1 (s, ((__const char *) (reject))[0]) \ : strcspn (s, reject))) \ : strcspn (s, reject))) __STRING_INLINE size_t __strcspn_c1 (__const char *__s, char __reject); __STRING_INLINE size_t __strcspn_c1 (__const char *__s, char __reject) { register size_t __result = 0; while (__s[__result] != '\0' && __s[__result] != __reject) ++__result; return __result; } #endif /* Return the length of the initial segment of S which consists entirely of characters in ACCEPT. */ #ifndef _HAVE_STRING_ARCH_strspn # define strspn(s, accept) \ (__extension__ (__builtin_constant_p (accept) && __string2_1bptr_p (accept) \ ? (((__const unsigned char *) (accept))[0] == '\0' \ ? 0 \ : (((__const unsigned char *) (accept))[1] == '\0' \ ? __strspn_c1 (s, ((__const char *) (accept))[0]) \ : strspn (s, accept))) \ : strspn (s, accept))) __STRING_INLINE size_t __strspn_c1 (__const char *__s, char __accept); __STRING_INLINE size_t __strspn_c1 (__const char *__s, char __accept) { register size_t __result = 0; /* Please note that __accept never can be '\0'. */ while (__s[__result] == __accept) ++__result; return __result; } #endif /* Find the first occurrence in S of any character in ACCEPT. */ #ifndef _HAVE_STRING_ARCH_strpbrk # define strpbrk(s, accept) \ (__extension__ (__builtin_constant_p (accept) && __string2_1bptr_p (accept) \ ? (((__const unsigned char *) (accept))[0] == '\0' \ ? NULL \ : (((__const unsigned char *) (accept))[1] == '\0' \ ? strchr (s, ((__const unsigned char *) (accept))[0]) \ : strpbrk (s, accept))) \ : strpbrk (s, accept))) #endif /* Find the first occurrence of NEEDLE in HAYSTACK. */ #ifndef _HAVE_STRING_ARCH_strstr # define strstr(haystack, needle) \ (__extension__ (__builtin_constant_p (needle) && __string2_1bptr_p (needle) \ ? (((__const unsigned char *) (needle))[0] == '\0' \ ? (char *) (haystack) \ : (((__const unsigned char *) (needle))[1] == '\0' \ ? strchr (haystack, \ ((__const unsigned char *) (needle))[0]) \ : strstr (haystack, needle))) \ : strstr (haystack, needle))) #endif #ifdef __USE_GNU # ifndef _HAVE_STRING_ARCH_strnlen __STRING_INLINE size_t strnlen (__const char *__string, size_t __maxlen); __STRING_INLINE size_t strnlen (__const char *__string, size_t __maxlen) { __const char *__end = (__const char *) memchr (__string, '\0', __maxlen); return __end ? __end - __string : __maxlen; } # endif #endif #if defined __USE_POSIX || defined __USE_MISC # ifndef _HAVE_STRING_ARCH_strtok_r # define strtok_r(s, sep, nextp) \ (__extension__ (__builtin_constant_p (sep) && __string2_1bptr_p (sep) \ ? (((__const unsigned char *) (sep))[0] != '\0' \ && ((__const unsigned char *) (sep))[1] == '\0' \ ? __strtok_r_1c (s, ((__const unsigned char *) (sep))[0],\ nextp) \ : strtok_r (s, sep, nextp)) \ : strtok_r (s, sep, nextp))) __STRING_INLINE char *__strtok_r_1c (char *__s, char __sep, char **__nextp); __STRING_INLINE char * __strtok_r_1c (char *__s, char __sep, char **__nextp) { char *__result; if (__s == NULL) __s = *__nextp; while (*__s == __sep) ++__s; if (*__s == '\0') __result = NULL; else { __result = __s; while (*__s != '\0' && *__s != __sep) ++__s; if (*__s == '\0') *__nextp = __s; else { *__s = '\0'; *__nextp = __s + 1; } } return __result; } # endif #endif #ifdef __USE_BSD # ifndef _HAVE_STRING_ARCH_strsep # define strsep(s, reject) \ (__extension__ (__builtin_constant_p (reject) && __string2_1bptr_p (reject) \ ? (((__const unsigned char *) (reject))[0] != '\0' \ && ((__const unsigned char *) (reject))[1] == '\0' \ ? __strsep_1c (s, \ ((__const unsigned char *) (reject))[0]) \ : __strsep_g (s, reject)) \ : __strsep_g (s, reject))) __STRING_INLINE char *__strsep_1c (char **__s, char __reject); __STRING_INLINE char * __strsep_1c (char **__s, char __reject) { register char *__retval = *__s; if (__retval == NULL || *__retval == '\0') return NULL; while (*__retval == __reject) ++__retval; if ((*__s = strchr (__retval, __reject)) != NULL) *(*__s)++ = '\0'; return __retval; } __STRING_INLINE char *__strsep_g (char **__s, __const char *__reject); __STRING_INLINE char * __strsep_g (char **__s, __const char *__reject) { register char *__retval = *__s; if (__retval == NULL || *__retval == '\0') return NULL; if ((*__s = strpbrk (__retval, __reject)) != NULL) *(*__s)++ = '\0'; return __retval; } # endif #endif #undef __STRING_INLINE #endif /* No string inlines. */