(CYCLIC): New macro. All uses of rol changed to use CYCLIC.

Redo comment to minimize changes from libc.

diff --git a/lib/md5.c b/lib/md5.c
index 5eed3594494c7ec8689a585baebb10cd9c65e5cf..87db8f956c6f8fa9d6722d81a1dbfee96d542217 100644 (file)
--- a/lib/md5.c
+++ b/lib/md5.c
@@ -57,7 +57,6 @@
 #endif
 
 #define BLOCKSIZE 4096
-/* Ensure that BLOCKSIZE is a multiple of 64.  */
 #if BLOCKSIZE % 64 != 0
 # error "invalid BLOCKSIZE"
 #endif
@@ -334,15 +333,22 @@ md5_process_block (const void *buffer, size_t len, struct md5_ctx *ctx)
         {                                                              \
          a += FF (b, c, d) + (*cwp++ = SWAP (*words)) + T;             \
          ++words;                                                      \
-         a = rol (a, s);                                               \
+         CYCLIC (a, s);                                                \
          a += b;                                                       \
         }                                                              \
       while (0)
 
+      /* It is unfortunate that C does not provide an operator for
+        cyclic rotation.  Hope the C compiler is smart enough.  */
+#define CYCLIC(w, s) (w = (w << s) | (w >> (32 - s)))
+
       /* Before we start, one word to the strange constants.
         They are defined in RFC 1321 as
 
-        T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64, or
+        T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64
+
+        Here is an equivalent invocation using Perl:
+
         perl -e 'foreach(1..64){printf "0x%08x\n", int (4294967296 * abs (sin $_))}'
        */
 
@@ -372,7 +378,7 @@ md5_process_block (const void *buffer, size_t len, struct md5_ctx *ctx)
       do                                                               \
        {                                                               \
          a += f (b, c, d) + correct_words[k] + T;                      \
-         a = rol (a, s);                                               \
+         CYCLIC (a, s);                                                \
          a += b;                                                       \
        }                                                               \
       while (0)