zig/lib/libcxx/include/__random/random_device.h
Alex Rønne Petersen 156ab87500
libcxx: Update to Clang 20.
See:

* https://discourse.llvm.org/t/rfc-freezing-c-03-headers-in-libc/77319
* https://discourse.llvm.org/t/rfc-project-hand-in-hand-llvm-libc-libc-code-sharing/77701

We're dropping support for C++03 for Zig due to the first change; it would be
insane to ship 1018 duplicate header files just for this outdated use case.

As a result of the second change, I had to bring in a subset of the headers from
llvm-libc since libc++ now depends on these. Hopefully we can continue to get
away with not copying the entirety of llvm-libc.
2025-04-04 06:08:09 +02:00

82 lines
2.3 KiB
C++
Vendored

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___RANDOM_RANDOM_DEVICE_H
#define _LIBCPP___RANDOM_RANDOM_DEVICE_H
#include <__config>
#include <string>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_HAS_RANDOM_DEVICE
class _LIBCPP_EXPORTED_FROM_ABI random_device {
# ifdef _LIBCPP_USING_DEV_RANDOM
int __f_;
# elif !defined(_LIBCPP_ABI_NO_RANDOM_DEVICE_COMPATIBILITY_LAYOUT)
_LIBCPP_DIAGNOSTIC_PUSH
_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wunused-private-field")
// Apple platforms used to use the `_LIBCPP_USING_DEV_RANDOM` code path, and now
// use `arc4random()` as of this comment. In order to avoid breaking the ABI, we
// retain the same layout as before.
# if defined(__APPLE__)
int __padding_; // padding to fake the `__f_` field above
# endif
// ... vendors can add workarounds here if they switch to a different representation ...
_LIBCPP_DIAGNOSTIC_POP
# endif
public:
// types
typedef unsigned result_type;
// generator characteristics
static _LIBCPP_CONSTEXPR const result_type _Min = 0;
static _LIBCPP_CONSTEXPR const result_type _Max = 0xFFFFFFFFu;
_LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type min() { return _Min; }
_LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type max() { return _Max; }
// constructors
# ifndef _LIBCPP_CXX03_LANG
_LIBCPP_HIDE_FROM_ABI random_device() : random_device("/dev/urandom") {}
explicit random_device(const string& __token);
# else
explicit random_device(const string& __token = "/dev/urandom");
# endif
~random_device();
// generating functions
result_type operator()();
// property functions
double entropy() const _NOEXCEPT;
random_device(const random_device&) = delete;
void operator=(const random_device&) = delete;
};
#endif // _LIBCPP_HAS_RANDOM_DEVICE
_LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
#endif // _LIBCPP___RANDOM_RANDOM_DEVICE_H