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1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___CXX03___RANDOM_RANDOM_DEVICE_H10#define _LIBCPP___CXX03___RANDOM_RANDOM_DEVICE_H11 12#include <__cxx03/__config>13#include <__cxx03/string>14 15#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)16# pragma GCC system_header17#endif18 19_LIBCPP_PUSH_MACROS20#include <__cxx03/__undef_macros>21 22_LIBCPP_BEGIN_NAMESPACE_STD23 24#if !defined(_LIBCPP_HAS_NO_RANDOM_DEVICE)25 26class _LIBCPP_EXPORTED_FROM_ABI random_device {27# ifdef _LIBCPP_USING_DEV_RANDOM28 int __f_;29# elif !defined(_LIBCPP_ABI_NO_RANDOM_DEVICE_COMPATIBILITY_LAYOUT)30 _LIBCPP_DIAGNOSTIC_PUSH31 _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wunused-private-field")32 33 // Apple platforms used to use the `_LIBCPP_USING_DEV_RANDOM` code path, and now34 // use `arc4random()` as of this comment. In order to avoid breaking the ABI, we35 // retain the same layout as before.36# if defined(__APPLE__)37 int __padding_; // padding to fake the `__f_` field above38# endif39 40 // ... vendors can add workarounds here if they switch to a different representation ...41 42 _LIBCPP_DIAGNOSTIC_POP43# endif44 45public:46 // types47 typedef unsigned result_type;48 49 // generator characteristics50 static const result_type _Min = 0;51 static const result_type _Max = 0xFFFFFFFFu;52 53 _LIBCPP_HIDE_FROM_ABI static result_type min() { return _Min; }54 _LIBCPP_HIDE_FROM_ABI static result_type max() { return _Max; }55 56 // constructors57 explicit random_device(const string& __token = "/dev/urandom");58 ~random_device();59 60 // generating functions61 result_type operator()();62 63 // property functions64 double entropy() const _NOEXCEPT;65 66 random_device(const random_device&) = delete;67 void operator=(const random_device&) = delete;68};69 70#endif // !_LIBCPP_HAS_NO_RANDOM_DEVICE71 72_LIBCPP_END_NAMESPACE_STD73 74_LIBCPP_POP_MACROS75 76#endif // _LIBCPP___CXX03___RANDOM_RANDOM_DEVICE_H77