MD5Update function uses StringPiece instead of raw buffer.

base/md5.cc

+// 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.
  * The algorithm is due to Ron Rivest.  This code was
  * written by Colin Plumb in 1993, no copyright is claimed.
  * This code is in the public domain; do with it what you wish.
  *
  * Equivalent code is available from RSA Data Security, Inc.
  * This code has been tested against that, and is equivalent,
  * except that you don't need to include two pages of legalese
@@ skipping 144 matching lines @@
         ctx->buf[2] = 0x98badcfe;
         ctx->buf[3] = 0x10325476;
         ctx->bits[0] = 0;
         ctx->bits[1] = 0;
 }
 
 /*
  * 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;
 
         /* Update bitcount */
 
         t = ctx->bits[0];
         if ((ctx->bits[0] = t + ((uint32)len << 3)) < t)
                 ctx->bits[1]++; /* Carry from low to high */
         ctx->bits[1] += static_cast<uint32>(len >> 29);
@@ skipping 88 matching lines @@
     int a = digest.a[i];
     ret[j++] = zEncode[(a>>4)&0xf];
     ret[j++] = zEncode[a & 0xf];
   }
   return ret;
 }
 
 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);
 }
 
 }  // namespace base