forked from OSchip/llvm-project
46 lines
938 B
C++
46 lines
938 B
C++
//===-------------------------- random.cpp --------------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is dual licensed under the MIT and the University of Illinois Open
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// Source Licenses. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#include "random"
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#include "system_error"
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#include <fcntl.h>
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#include <unistd.h>
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#include <errno.h>
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_LIBCPP_BEGIN_NAMESPACE_STD
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random_device::random_device(const string& __token)
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: __f_(open(__token.c_str(), O_RDONLY))
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{
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if (__f_ <= 0)
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__throw_system_error(errno, ("random_device failed to open " + __token).c_str());
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}
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random_device::~random_device()
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{
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close(__f_);
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}
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unsigned
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random_device::operator()()
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{
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unsigned r;
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read(__f_, &r, sizeof(r));
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return r;
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}
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double
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random_device::entropy() const
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{
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return 0;
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}
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_LIBCPP_END_NAMESPACE_STD
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