use _GL_ATTRIBUTE_CONST and _GL_ATTRIBUTE_PURE

[pspp] / lib / memchr2.c

diff --git a/lib/memchr2.c b/lib/memchr2.c
index ad78195ee393ac4471f44196933a605394d09980..b830b9d0b2950f4bdd25e3267dfeaa6b88f40e37 100644 (file)
--- a/lib/memchr2.c
+++ b/lib/memchr2.c
@@ -1,5 +1,5 @@
-/* Copyright (C) 1991, 1993, 1996, 1997, 1999, 2000, 2003, 2004, 2006,
-   2008 Free Software Foundation, Inc.
+/* Copyright (C) 1991, 1993, 1996-1997, 1999-2000, 2003-2004, 2006, 2008-2011
+   Free Software Foundation, Inc.
 
    Based on strlen implementation by Torbjorn Granlund (tege@sics.se),
    with help from Dan Sahlin (dan@sics.se) and
@@ -29,10 +29,18 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <stdint.h>
 #include <string.h>
 
+/* The attribute __pure__ was added in gcc 2.96.  */
+#undef _GL_ATTRIBUTE_PURE
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
+# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
+#else
+# define _GL_ATTRIBUTE_PURE /* empty */
+#endif
+
 /* Return the first address of either C1 or C2 (treated as unsigned
    char) that occurs within N bytes of the memory region S.  If
    neither byte appears, return NULL.  */
-void *
+void * _GL_ATTRIBUTE_PURE
 memchr2 (void const *s, int c1_in, int c2_in, size_t n)
 {
   /* On 32-bit hardware, choosing longword to be a 32-bit unsigned
@@ -84,16 +92,16 @@ memchr2 (void const *s, int c1_in, int c2_in, size_t n)
       repeated_c1 |= repeated_c1 << 31 << 1;
       repeated_c2 |= repeated_c2 << 31 << 1;
       if (8 < sizeof (longword))
-       {
-         size_t i;
-
-         for (i = 64; i < sizeof (longword) * 8; i *= 2)
-           {
-             repeated_one |= repeated_one << i;
-             repeated_c1 |= repeated_c1 << i;
-             repeated_c2 |= repeated_c2 << i;
-           }
-       }
+        {
+          size_t i;
+
+          for (i = 64; i < sizeof (longword) * 8; i *= 2)
+            {
+              repeated_one |= repeated_one << i;
+              repeated_c1 |= repeated_c1 << i;
+              repeated_c2 |= repeated_c2 << i;
+            }
+        }
     }
 
   /* Instead of the traditional loop which tests each byte, we will test a
@@ -138,9 +146,9 @@ memchr2 (void const *s, int c1_in, int c2_in, size_t n)
       longword longword2 = *longword_ptr ^ repeated_c2;
 
       if (((((longword1 - repeated_one) & ~longword1)
-           | ((longword2 - repeated_one) & ~longword2))
-          & (repeated_one << 7)) != 0)
-       break;
+            | ((longword2 - repeated_one) & ~longword2))
+           & (repeated_one << 7)) != 0)
+        break;
       longword_ptr++;
       n -= sizeof (longword);
     }
@@ -157,7 +165,7 @@ memchr2 (void const *s, int c1_in, int c2_in, size_t n)
   for (; n > 0; --n, ++char_ptr)
     {
       if (*char_ptr == c1 || *char_ptr == c2)
-       return (void *) char_ptr;
+        return (void *) char_ptr;
     }
 
   return NULL;