/* 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 #ifdef __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) \ (((src)[idx + 1] << 8) | (src)[idx]) # define __STRING2_SMALL_GET32(src, idx) \ ((((src)[idx + 3] << 8 | (src)[idx + 2]) << 8 \ | (src)[idx + 1]) << 8 | (src)[idx]) # else # define __STRING2_SMALL_GET16(src, idx) \ (((src)[idx] << 8) | (src)[idx + 1]) # define __STRING2_SMALL_GET32(src, idx) \ ((((src)[idx] << 8 | (src)[idx + 1]) << 8 \ | (src)[idx + 2]) << 8 | (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 /* 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) \ ? (sizeof ((src)[0]) == 1 && 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__ ({ char *__retval = (dest); \ char *__cp = __retval; \ switch (srclen) \ { \ case 1: \ *((unsigned char *) __cp) = '\0'; \ break; \ case 2: \ *((__uint16_t *) __cp) = \ __STRING2_SMALL_GET16 (src, 0); \ break; \ case 3: \ *((__uint16_t *) __cp)++ = \ __STRING2_SMALL_GET16 (src, 0); \ *((unsigned char *) __cp) = '\0'; \ break; \ case 4: \ *((__uint32_t *) __cp) = \ __STRING2_SMALL_GET32 (src, 0); \ break; \ case 5: \ *((__uint32_t *) __cp)++ = \ __STRING2_SMALL_GET32 (src, 0); \ *((unsigned char *) __cp) = '\0'; \ break; \ case 6: \ *((__uint32_t *) __cp)++ = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint16_t *) __cp) = \ __STRING2_SMALL_GET16 (src, 4); \ break; \ case 7: \ *((__uint32_t *) __cp)++ = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint16_t *) __cp)++ = \ __STRING2_SMALL_GET16 (src, 4); \ *((unsigned char *) __cp) = '\0'; \ break; \ case 8: \ *((__uint32_t *) __cp)++ = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint32_t *) __cp) = \ __STRING2_SMALL_GET32 (src, 4); \ break; \ } \ __retval; })) # else # define __strcpy_small(dest, src, srclen) \ (__extension__ ({ char *__cp = (dest); \ switch (srclen) \ { \ case 1: \ *((unsigned char *) __cp) = '\0'; \ break; \ case 2: \ *((__STRING2_COPY_ARR2 *) __cp) = \ ((__STRING2_COPY_ARR2) { { (src)[0], '\0' } }); \ break; \ case 3: \ *((__STRING2_COPY_ARR3 *) __cp) = \ ((__STRING2_COPY_ARR3) { { (src)[0], (src)[1], \ '\0' } }); \ break; \ case 4: \ *((__STRING2_COPY_ARR4 *) __cp) = \ ((__STRING2_COPY_ARR4) { { (src)[0], (src)[1], \ (src)[2], '\0' } }); \ break; \ case 5: \ *((__STRING2_COPY_ARR5 *) __cp) = \ ((__STRING2_COPY_ARR5) { { (src)[0], (src)[1], \ (src)[2], (src)[3], \ '\0' } }); \ break; \ case 6: \ *((__STRING2_COPY_ARR6 *) __cp) = \ ((__STRING2_COPY_ARR6) { { (src)[0], (src)[1], \ (src)[2], (src)[3], \ (src)[4], '\0' } }); \ break; \ case 7: \ *((__STRING2_COPY_ARR7 *) __cp) = \ ((__STRING2_COPY_ARR7) { { (src)[0], (src)[1], \ (src)[2], (src)[3], \ (src)[4], (src)[5], \ '\0' } }); \ break; \ case 8: \ *((__STRING2_COPY_ARR8 *) __cp) = \ ((__STRING2_COPY_ARR8) { { (src)[0], (src)[1], \ (src)[2], (src)[3], \ (src)[4], (src)[5], \ (src)[6], '\0' } }); \ break; \ } \ __cp; })) # 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) \ ? (sizeof ((src)[0]) == 1 && 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__ ({ char *__cp = (dest); \ switch (srclen) \ { \ case 1: \ *((unsigned char *) __cp) = '\0'; \ break; \ case 2: \ *((__uint16_t *) __cp) = \ __STRING2_SMALL_GET16 (src, 0); \ ++__cp; \ break; \ case 3: \ *((__uint16_t *) __cp)++ = \ __STRING2_SMALL_GET16 (src, 0); \ *((unsigned char *) __cp) = '\0'; \ break; \ case 4: \ *((__uint32_t *) __cp) = \ __STRING2_SMALL_GET32 (src, 0); \ __cp += 3; \ break; \ case 5: \ *((__uint32_t *) __cp)++ = \ __STRING2_SMALL_GET32 (src, 0); \ *((unsigned char *) __cp) = '\0'; \ break; \ case 6: \ *((__uint32_t *) __cp)++ = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint16_t *) __cp) = \ __STRING2_SMALL_GET16 (src, 4); \ ++__cp; \ break; \ case 7: \ *((__uint32_t *) __cp)++ = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint16_t *) __cp)++ = \ __STRING2_SMALL_GET16 (src, 4); \ *((unsigned char *) __cp) = '\0'; \ break; \ case 8: \ *((__uint32_t *) __cp)++ = \ __STRING2_SMALL_GET32 (src, 0); \ *((__uint32_t *) __cp) = \ __STRING2_SMALL_GET32 (src, 4); \ __cp += 3; \ break; \ } \ __cp; })) # else # define __stpcpy_small(dest, src, srclen) \ (__extension__ ({ char *__cp = (dest); \ switch (srclen) \ { \ case 1: \ *((unsigned char *) __cp) = '\0'; \ break; \ case 2: \ *((__STRING2_COPY_ARR2 *) __cp) = \ ((__STRING2_COPY_ARR2) { { (src)[0], '\0' } }); \ break; \ case 3: \ *((__STRING2_COPY_ARR3 *) __cp) = \ ((__STRING2_COPY_ARR3) { { (src)[0], (src)[1], \ '\0' } }); \ break; \ case 4: \ *((__STRING2_COPY_ARR4 *) __cp) = \ ((__STRING2_COPY_ARR4) { { (src)[0], (src)[1], \ (src)[2], '\0' } }); \ break; \ case 5: \ *((__STRING2_COPY_ARR5 *) __cp) = \ ((__STRING2_COPY_ARR5) { { (src)[0], (src)[1], \ (src)[2], (src)[3], \ '\0' } }); \ break; \ case 6: \ *((__STRING2_COPY_ARR6 *) __cp) = \ ((__STRING2_COPY_ARR6) { { (src)[0], (src)[1], \ (src)[2], (src)[3], \ (src)[4], '\0' } }); \ break; \ case 7: \ *((__STRING2_COPY_ARR7 *) __cp) = \ ((__STRING2_COPY_ARR7) { { (src)[0], (src)[1], \ (src)[2], (src)[3], \ (src)[4], (src)[5], \ '\0' } }); \ break; \ case 8: \ *((__STRING2_COPY_ARR8 *) __cp) = \ ((__STRING2_COPY_ARR8) { { (src)[0], (src)[1], \ (src)[2], (src)[3], \ (src)[4], (src)[5], \ (src)[6], '\0' } }); \ break; \ } \ __cp + ((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__ (__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)), \ (char *) 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__ (__builtin_constant_p (src) && __builtin_constant_p (n) \ ? (strlen (src) < ((size_t) (n)) \ ? strcat (dest, src) \ : (memcpy (strchr (dest, '\0'), src, n), (char *) 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 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) && sizeof ((reject)[0]) == 1 \ ? ((reject)[0] == '\0' \ ? strlen (s) \ : ((reject)[1] == '\0' \ ? __strcspn_c1 (s, (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) && sizeof ((accept)[0]) == 1 \ ? ((accept)[0] == '\0' \ ? 0 \ : ((accept)[1] == '\0' \ ? __strspn_c1 (s, (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) && sizeof ((accept)[0]) == 1 \ ? ((accept)[0] == '\0' \ ? NULL \ : ((accept)[1] == '\0' \ ? strchr (s, (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) && sizeof ((needle)[0]) == 1 \ ? ((needle)[0] == '\0' \ ? haystack \ : ((needle)[1] == '\0' \ ? strchr (haystack, (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 #ifdef __USE_BSD # ifndef _HAVE_STRING_ARCH_strsep # define strsep(s, reject) \ (__extension__ (__builtin_constant_p (reject) && sizeof ((reject)[0]) == 1 \ ? ((reject)[0] != '\0' && (reject)[1] == '\0' \ ? __strsep_1c (s, (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 __const char *__retval = *__s; if (__retval == NULL || *__retval == '\0') return NULL; while (*__retval == __reject) ++__retval; if ((*__s = strchr (__retval, __reject)) != NULL) *(*__s)++ = '\0'; return (char *) __retval; } __STRING_INLINE char *__strsep_g (char **__s, __const char *__reject); __STRING_INLINE char * __strsep_g (char **__s, __const char *__reject) { register __const char *__retval = *__s; if (__retval == NULL || *__retval == '\0') return NULL; if ((*__s = strpbrk (__retval, __reject)) != NULL) *(*__s)++ = '\0'; return (char *) __retval; } # endif #endif #undef __STRING_INLINE #endif /* No string inlines. */