base/hash.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef BASE_HASH_H_
   6 #define BASE_HASH_H_
   7
   8 #include <limits>
   9 #include <string>
  10
  11 #include "base/base_export.h"
  12 #include "base/basictypes.h"
  13 #include "base/logging.h"
  14
  15 namespace base {
  16
  17 // WARNING: This hash function should not be used for any cryptographic purpose.
  18 BASE_EXPORT uint32 SuperFastHash(const char* data, int len);
  19
  20 // Computes a hash of a memory buffer |data| of a given |length|.
  21 // WARNING: This hash function should not be used for any cryptographic purpose.
  22 inline uint32 Hash(const char* data, size_t length) {
  23   if (length > static_cast<size_t>(std::numeric_limits<int>::max())) {
  24     NOTREACHED();
  25     return 0;
  26   }
  27   return SuperFastHash(data, static_cast<int>(length));
  28 }
  29
  30 // Computes a hash of a string |str|.
  31 // WARNING: This hash function should not be used for any cryptographic purpose.
  32 inline uint32 Hash(const std::string& str) {
  33   return Hash(str.data(), str.size());
  34 }
  35
  36 }  // namespace base
  37
  38 #endif  // BASE_HASH_H_