MD5Update function uses StringPiece instead of raw buffer.

base/md5.cc

Index: base/md5.cc
diff --git a/base/md5.cc b/base/md5.cc
index 2211a285e5badf8ef181c3910b10c73e347be4ce..754994c0e562b45b2bc4b90cc2a7c612d14ec5a7 100644
--- a/base/md5.cc
+++ b/base/md5.cc
@@ -1,5 +1,8 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
 // The original file was copied from sqlite, and was in the public domain.
-// Modifications Copyright 2006 Google Inc. All Rights Reserved
 
 /*
  * This code implements the MD5 message-digest algorithm.
@@ -164,7 +167,9 @@ void MD5Init(MD5Context* context) {
  * Update context to reflect the concatenation of another buffer full
  * of bytes.
  */
-void MD5Update(MD5Context* context, const void* inbuf, size_t len) {
+void MD5Update(MD5Context* context, const StringPiece& data) {
+        const unsigned char* inbuf = (const unsigned char*)data.data();
+        size_t len = data.size();
         struct Context *ctx = (struct Context *)context;
         const unsigned char* buf = (const unsigned char*)inbuf;
         uint32 t;
@@ -273,11 +278,12 @@ std::string MD5DigestToBase16(const MD5Digest& digest) {
 void MD5Sum(const void* data, size_t length, MD5Digest* digest) {
   MD5Context ctx;
   MD5Init(&ctx);
-  MD5Update(&ctx, static_cast<const unsigned char*>(data), length);
+  MD5Update(&ctx,
+            StringPiece(reinterpret_cast<const char*>(data), length));
   MD5Final(digest, &ctx);
 }
 
-std::string MD5String(const std::string& str) {
+std::string MD5String(const StringPiece& str) {
   MD5Digest digest;
   MD5Sum(str.data(), str.length(), &digest);
   return MD5DigestToBase16(digest);