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Diffstat (limited to 'newlib/libc/string/memchr.c')
-rw-r--r--newlib/libc/string/memchr.c143
1 files changed, 0 insertions, 143 deletions
diff --git a/newlib/libc/string/memchr.c b/newlib/libc/string/memchr.c
deleted file mode 100644
index 2fd3c861d..000000000
--- a/newlib/libc/string/memchr.c
+++ /dev/null
@@ -1,143 +0,0 @@
-/*
-FUNCTION
- <<memchr>>---find character in memory
-
-INDEX
- memchr
-
-ANSI_SYNOPSIS
- #include <string.h>
- void *memchr(const void *<[src]>, int <[c]>, size_t <[length]>);
-
-TRAD_SYNOPSIS
- #include <string.h>
- void *memchr(<[src]>, <[c]>, <[length]>)
- void *<[src]>;
- void *<[c]>;
- size_t <[length]>;
-
-DESCRIPTION
- This function searches memory starting at <<*<[src]>>> for the
- character <[c]>. The search only ends with the first
- occurrence of <[c]>, or after <[length]> characters; in
- particular, <<NULL>> does not terminate the search.
-
-RETURNS
- If the character <[c]> is found within <[length]> characters
- of <<*<[src]>>>, a pointer to the character is returned. If
- <[c]> is not found, then <<NULL>> is returned.
-
-PORTABILITY
-<<memchr>>> is ANSI C.
-
-<<memchr>> requires no supporting OS subroutines.
-
-QUICKREF
- memchr ansi pure
-*/
-
-#include <_ansi.h>
-#include <string.h>
-#include <limits.h>
-
-/* Nonzero if either X or Y is not aligned on a "long" boundary. */
-#define UNALIGNED(X) ((long)X & (sizeof (long) - 1))
-
-/* How many bytes are loaded each iteration of the word copy loop. */
-#define LBLOCKSIZE (sizeof (long))
-
-/* Threshhold for punting to the bytewise iterator. */
-#define TOO_SMALL(LEN) ((LEN) < LBLOCKSIZE)
-
-#if LONG_MAX == 2147483647L
-#define DETECTNULL(X) (((X) - 0x01010101) & ~(X) & 0x80808080)
-#else
-#if LONG_MAX == 9223372036854775807L
-/* Nonzero if X (a long int) contains a NULL byte. */
-#define DETECTNULL(X) (((X) - 0x0101010101010101) & ~(X) & 0x8080808080808080)
-#else
-#error long int is not a 32bit or 64bit type.
-#endif
-#endif
-
-#ifndef DETECTNULL
-#error long int is not a 32bit or 64bit byte
-#endif
-
-
-_PTR
-_DEFUN (memchr, (src_void, c, length),
- _CONST _PTR src_void _AND
- int c _AND
- size_t length)
-{
-#if defined(PREFER_SIZE_OVER_SPEED) || defined(__OPTIMIZE_SIZE__)
- _CONST unsigned char *src = (_CONST unsigned char *) src_void;
-
- c &= 0xff;
-
- while (length--)
- {
- if (*src == c)
- return (char *) src;
- src++;
- }
- return NULL;
-#else
- _CONST unsigned char *src = (_CONST unsigned char *) src_void;
- unsigned long *asrc;
- unsigned long buffer;
- unsigned long mask;
- int i, j;
-
- c &= 0xff;
-
- /* If the size is small, or src is unaligned, then
- use the bytewise loop. We can hope this is rare. */
- if (!TOO_SMALL (length) && !UNALIGNED (src))
- {
- /* The fast code reads the ASCII one word at a time and only
- performs the bytewise search on word-sized segments if they
- contain the search character, which is detected by XORing
- the word-sized segment with a word-sized block of the search
- character and then detecting for the presence of NULL in the
- result. */
- asrc = (unsigned long*) src;
- mask = 0;
- for (i = 0; i < LBLOCKSIZE; i++)
- mask = (mask << 8) + c;
-
- while (length >= LBLOCKSIZE)
- {
- buffer = *asrc;
- buffer ^= mask;
- if (DETECTNULL (buffer))
- {
- src = (unsigned char*) asrc;
- for ( j = 0; j < LBLOCKSIZE; j++ )
- {
- if (*src == c)
- return (char*) src;
- src++;
- }
- }
- length -= LBLOCKSIZE;
- asrc++;
- }
-
- /* If there are fewer than LBLOCKSIZE characters left,
- then we resort to the bytewise loop. */
-
- src = (unsigned char*) asrc;
- }
-
- while (length--)
- {
- if (*src == c)
- return (char*) src;
- src++;
- }
-
- return NULL;
-#endif /* not PREFER_SIZE_OVER_SPEED */
-}