15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Copyright (c) 2012 The Chromium Authors. All rights reserved.
25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Use of this source code is governed by a BSD-style license that can be
35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// found in the LICENSE file.
45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
5424c4d7b64af9d0d8fd9624f381f469654d5e3d2Torne (Richard Coles)#include "components/variations/metrics_util.h"
65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/sha1.h"
85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/sys_byteorder.h"
95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace metrics {
115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)uint32 HashName(const std::string& name) {
135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  // SHA-1 is designed to produce a uniformly random spread in its output space,
145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  // even for nearly-identical inputs.
155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  unsigned char sha1_hash[base::kSHA1Length];
165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  base::SHA1HashBytes(reinterpret_cast<const unsigned char*>(name.c_str()),
175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)                      name.size(),
185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)                      sha1_hash);
195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  uint32 bits;
215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  COMPILE_ASSERT(sizeof(bits) < sizeof(sha1_hash), need_more_data);
225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  memcpy(&bits, sha1_hash, sizeof(bits));
235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  return base::ByteSwapToLE32(bits);
255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}
265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}  // namespace metrics
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