Merge from coreutils.

[gnulib.git] / lib / memchr.c

diff --git a/lib/memchr.c b/lib/memchr.c
index 57f9973..ae232ae 100644 (file)
--- a/lib/memchr.c
+++ b/lib/memchr.c
@@ -1,5 +1,7 @@
-/* Copyright (C) 1991, 1993 Free Software Foundation, Inc.
-   Based on strlen implemention by Torbjorn Granlund (tege@sics.se),
+/* Copyright (C) 1991, 1993, 1996, 1997, 1999, 2000, 2003 Free
+   Software Foundation, Inc.
+
+   Based on strlen implementation by Torbjorn Granlund (tege@sics.se),
    with help from Dan Sahlin (dan@sics.se) and
    commentary by Jim Blandy (jimb@ai.mit.edu);
    adaptation to memchr suggested by Dick Karpinski (dick@cca.ucsf.edu),
@@ -20,57 +22,55 @@ GNU General Public License for more details.
 
 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
-Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+USA.  */
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+# include <config.h>
 #endif
 
-#undef __ptr_t
-#if defined (__cplusplus) || (defined (__STDC__) && __STDC__)
-# define __ptr_t void *
-#else /* Not C++ or ANSI C.  */
-# define __ptr_t char *
-#endif /* C++ or ANSI C.  */
+#include <string.h>
 
-#if defined (HAVE_STRING_H) || defined (_LIBC)
-# include <string.h>
+#if defined _LIBC
+# include <memcopy.h>
+#else
+# define reg_char char
 #endif
 
-#if defined (HAVE_LIMIT_H) || defined (_LIBC)
-# include <limit.h>
-#endif
+#include <limits.h>
+#include <stdlib.h>
 
 #define LONG_MAX_32_BITS 2147483647
 
-#ifndef LONG_MAX
-#define LONG_MAX LONG_MAX_32_BITS
-#endif
-
 #include <sys/types.h>
+#if HAVE_BP_SYM_H || defined _LIBC
+# include <bp-sym.h>
+#else
+# define BP_SYM(sym) sym
+#endif
 
+#undef memchr
+#undef __memchr
 
 /* Search no more than N bytes of S for C.  */
-
-__ptr_t
-memchr (s, c, n)
-     const __ptr_t s;
-     int c;
-     size_t n;
+void *
+__memchr (void const *s, int c_in, size_t n)
 {
   const unsigned char *char_ptr;
   const unsigned long int *longword_ptr;
   unsigned long int longword, magic_bits, charmask;
+  unsigned reg_char c;
 
-  c = (unsigned char) c;
+  c = (unsigned char) c_in;
 
   /* 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;
+      return (void *) char_ptr;
 
   /* All these elucidatory comments refer to 4-byte longwords,
      but the theory applies equally well to 8-byte longwords.  */
@@ -80,9 +80,9 @@ 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.  */
@@ -146,10 +146,10 @@ 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.  */
@@ -161,22 +161,22 @@ memchr (s, c, n)
          const unsigned char *cp = (const unsigned char *) (longword_ptr - 1);
 
          if (cp[0] == c)
-           return (__ptr_t) cp;
+           return (void *) cp;
          if (cp[1] == c)
-           return (__ptr_t) &cp[1];
+           return (void *) &cp[1];
          if (cp[2] == c)
-           return (__ptr_t) &cp[2];
+           return (void *) &cp[2];
          if (cp[3] == c)
-           return (__ptr_t) &cp[3];
+           return (void *) &cp[3];
 #if LONG_MAX > 2147483647
          if (cp[4] == c)
-           return (__ptr_t) &cp[4];
+           return (void *) &cp[4];
          if (cp[5] == c)
-           return (__ptr_t) &cp[5];
+           return (void *) &cp[5];
          if (cp[6] == c)
-           return (__ptr_t) &cp[6];
+           return (void *) &cp[6];
          if (cp[7] == c)
-           return (__ptr_t) &cp[7];
+           return (void *) &cp[7];
 #endif
        }
 
@@ -188,10 +188,13 @@ memchr (s, c, n)
   while (n-- > 0)
     {
       if (*char_ptr == c)
-       return (__ptr_t) char_ptr;
+       return (void *) char_ptr;
       else
        ++char_ptr;
     }
 
   return 0;
 }
+#ifdef weak_alias
+weak_alias (__memchr, BP_SYM (memchr))
+#endif