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 <stddef.h> 9 #include <stdint.h> 10 11 #include <string> 12 13 #include "base/base_export.h" 14 #include "build/build_config.h" 15 16 namespace base { 17 18 // Returns a random number in range [0, UINT64_MAX]. Thread-safe. 19 BASE_EXPORT uint64_t RandUint64(); 20 21 // Returns a random number between min and max (inclusive). Thread-safe. 22 BASE_EXPORT int RandInt(int min, int max); 23 24 // Returns a random number in range [0, range). Thread-safe. 25 // 26 // Note that this can be used as an adapter for std::random_shuffle(): 27 // Given a pre-populated |std::vector<int> myvector|, shuffle it as 28 // std::random_shuffle(myvector.begin(), myvector.end(), base::RandGenerator); 29 BASE_EXPORT uint64_t RandGenerator(uint64_t range); 30 31 // Returns a random double in range [0, 1). Thread-safe. 32 BASE_EXPORT double RandDouble(); 33 34 // Given input |bits|, convert with maximum precision to a double in 35 // the range [0, 1). Thread-safe. 36 BASE_EXPORT double BitsToOpenEndedUnitInterval(uint64_t bits); 37 38 // Fills |output_length| bytes of |output| with random data. 39 // 40 // WARNING: 41 // Do not use for security-sensitive purposes. 42 // See crypto/ for cryptographically secure random number generation APIs. 43 BASE_EXPORT void RandBytes(void* output, size_t output_length); 44 45 // Fills a string of length |length| with random data and returns it. 46 // |length| should be nonzero. 47 // 48 // Note that this is a variation of |RandBytes| with a different return type. 49 // The returned string is likely not ASCII/UTF-8. Use with care. 50 // 51 // WARNING: 52 // Do not use for security-sensitive purposes. 53 // See crypto/ for cryptographically secure random number generation APIs. 54 BASE_EXPORT std::string RandBytesAsString(size_t length); 55 56 #if defined(OS_POSIX) 57 BASE_EXPORT int GetUrandomFD(); 58 #endif 59 60 } // namespace base 61 62 #endif // BASE_RAND_UTIL_H_ 63
