diff options
| author | Jim Meyering <jim@meyering.net> | 1995-05-28 01:55:00 +0000 |
|---|---|---|
| committer | Jim Meyering <jim@meyering.net> | 1995-05-28 01:55:00 +0000 |
| commit | 4fb3e0f061fbb49ada0463a125bd68a152105358 (patch) | |
| tree | 9847291d35171d17aeae61d7739a45105fecbf27 /lib/memchr.c | |
| parent | a528bd5d9f309442440c5d189adb57e0cbae3e5e (diff) | |
| download | coreutils-4fb3e0f061fbb49ada0463a125bd68a152105358.tar.xz | |
merge with 1.11.4a
Diffstat (limited to 'lib/memchr.c')
| -rw-r--r-- | lib/memchr.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/lib/memchr.c b/lib/memchr.c index 5114869ea..dc3bec7c8 100644 --- a/lib/memchr.c +++ b/lib/memchr.c @@ -33,6 +33,10 @@ Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ # define __ptr_t char * #endif /* C++ or ANSI C. */ +#if defined (_LIBC) +# include <string.h> +#endif + #if defined (HAVE_LIMITS_H) || defined (_LIBC) # include <limits.h> #endif @@ -62,8 +66,9 @@ memchr (s, c, n) /* Handle the first few characters by reading one character at a time. Do this until CHAR_PTR is aligned on a longword boundary. */ - for (char_ptr = s; n > 0 && ((unsigned long int) char_ptr - & (sizeof (longword) - 1)) != 0; + for (char_ptr = (const unsigned char *) s; + n > 0 && ((unsigned long int) char_ptr + & (sizeof (longword) - 1)) != 0; --n, ++char_ptr) if (*char_ptr == c) return (__ptr_t) char_ptr; @@ -76,9 +81,9 @@ memchr (s, c, n) /* Bits 31, 24, 16, and 8 of this number are zero. Call these bits the "holes." Note that there is a hole just to the left of each byte, with an extra at the end: - + bits: 01111110 11111110 11111110 11111111 - bytes: AAAAAAAA BBBBBBBB CCCCCCCC DDDDDDDD + bytes: AAAAAAAA BBBBBBBB CCCCCCCC DDDDDDDD The 1-bits make sure that carries propagate to the next 0-bit. The 0-bits provide holes for carries to fall into. */ @@ -142,10 +147,10 @@ memchr (s, c, n) /* Add MAGIC_BITS to LONGWORD. */ if ((((longword + magic_bits) - + /* Set those bits that were unchanged by the addition. */ ^ ~longword) - + /* Look at only the hole bits. If any of the hole bits are unchanged, most likely one of the bytes was a zero. */ |