1 // Copyright (c) 2012 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_RAND_UTIL_H_ 6 #define BASE_RAND_UTIL_H_ 7 8 #include <string> 9 10 #include "base/base_export.h" 11 #include "base/basictypes.h" 12 13 namespace base { 14 15 // Returns a random number in range [0, kuint64max]. Thread-safe. 16 BASE_EXPORT uint64 RandUint64(); 17 18 // Returns a random number between min and max (inclusive). Thread-safe. 19 BASE_EXPORT int RandInt(int min, int max); 20 21 // Returns a random number in range [0, range). Thread-safe. 22 // 23 // Note that this can be used as an adapter for std::random_shuffle(): 24 // Given a pre-populated |std::vector<int> myvector|, shuffle it as 25 // std::random_shuffle(myvector.begin(), myvector.end(), base::RandGenerator); 26 BASE_EXPORT uint64 RandGenerator(uint64 range); 27 28 // Returns a random double in range [0, 1). Thread-safe. 29 BASE_EXPORT double RandDouble(); 30 31 // Given input |bits|, convert with maximum precision to a double in 32 // the range [0, 1). Thread-safe. 33 BASE_EXPORT double BitsToOpenEndedUnitInterval(uint64 bits); 34 35 // Fills |output_length| bytes of |output| with random data. 36 // 37 // WARNING: 38 // Do not use for security-sensitive purposes. 39 // See crypto/ for cryptographically secure random number generation APIs. 40 BASE_EXPORT void RandBytes(void* output, size_t output_length); 41 42 // Fills a string of length |length| with random data and returns it. 43 // |length| should be nonzero. 44 // 45 // Note that this is a variation of |RandBytes| with a different return type. 46 // The returned string is likely not ASCII/UTF-8. Use with care. 47 // 48 // WARNING: 49 // Do not use for security-sensitive purposes. 50 // See crypto/ for cryptographically secure random number generation APIs. 51 BASE_EXPORT std::string RandBytesAsString(size_t length); 52 53 #if defined(OS_POSIX) 54 BASE_EXPORT int GetUrandomFD(); 55 #endif 56 57 } // namespace base 58 59 #endif // BASE_RAND_UTIL_H_ 60
