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 13namespace base { 14 15// Returns a random number in range [0, kuint64max]. Thread-safe. 16BASE_EXPORT uint64 RandUint64(); 17 18// Returns a random number between min and max (inclusive). Thread-safe. 19BASE_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); 26BASE_EXPORT uint64 RandGenerator(uint64 range); 27 28// Returns a random double in range [0, 1). Thread-safe. 29BASE_EXPORT double RandDouble(); 30 31// Given input |bits|, convert with maximum precision to a double in 32// the range [0, 1). Thread-safe. 33BASE_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. 40BASE_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. 51BASE_EXPORT std::string RandBytesAsString(size_t length); 52 53#if defined(OS_POSIX) 54BASE_EXPORT int GetUrandomFD(); 55#endif 56 57} // namespace base 58 59#endif // BASE_RAND_UTIL_H_ 60