Coverage Report

Created: 2022-05-14 11:35

/Users/buildslave/jenkins/workspace/coverage/llvm-project/libcxx/src/random.cpp
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//===----------------------------------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include <__config>
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#if defined(_LIBCPP_USING_WIN32_RANDOM)
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    // Must be defined before including stdlib.h to enable rand_s().
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#   define _CRT_RAND_S
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#endif // defined(_LIBCPP_USING_WIN32_RANDOM)
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#include <limits>
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#include <random>
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#include <system_error>
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#if defined(__sun__)
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#   define rename solaris_headers_are_broken
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#endif // defined(__sun__)
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#include <errno.h>
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#include <stdio.h>
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#include <stdlib.h>
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#if defined(_LIBCPP_USING_GETENTROPY)
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#   include <sys/random.h>
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#elif defined(_LIBCPP_USING_DEV_RANDOM)
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#   include <fcntl.h>
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#   include <unistd.h>
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#   if __has_include(<sys/ioctl.h>) && __has_include(<linux/random.h>)
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#       include <sys/ioctl.h>
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#       include <linux/random.h>
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#   endif
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#elif defined(_LIBCPP_USING_NACL_RANDOM)
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#   include <nacl/nacl_random.h>
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#elif defined(_LIBCPP_USING_FUCHSIA_CPRNG)
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#  include <zircon/syscalls.h>
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#endif
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_LIBCPP_BEGIN_NAMESPACE_STD
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#if defined(_LIBCPP_USING_GETENTROPY)
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random_device::random_device(const string& __token)
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{
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    if (__token != "/dev/urandom")
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        __throw_system_error(ENOENT, ("random device not supported " + __token).c_str());
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}
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random_device::~random_device()
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{
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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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    size_t n = sizeof(r);
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    int err = getentropy(&r, n);
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    if (err)
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        __throw_system_error(errno, "random_device getentropy failed");
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    return r;
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}
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#elif defined(_LIBCPP_USING_ARC4_RANDOM)
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random_device::random_device(const string&)
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{
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}
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random_device::~random_device()
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{
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0
}
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unsigned
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random_device::operator()()
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{
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    return arc4random();
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}
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#elif defined(_LIBCPP_USING_DEV_RANDOM)
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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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    size_t n = sizeof(r);
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    char* p = reinterpret_cast<char*>(&r);
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    while (n > 0)
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    {
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        ssize_t s = read(__f_, p, n);
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        if (s == 0)
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            __throw_system_error(ENODATA, "random_device got EOF");
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        if (s == -1)
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        {
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            if (errno != EINTR)
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                __throw_system_error(errno, "random_device got an unexpected error");
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            continue;
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        }
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        n -= static_cast<size_t>(s);
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        p += static_cast<size_t>(s);
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    }
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    return r;
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}
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#elif defined(_LIBCPP_USING_NACL_RANDOM)
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random_device::random_device(const string& __token)
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{
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    if (__token != "/dev/urandom")
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        __throw_system_error(ENOENT, ("random device not supported " + __token).c_str());
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    int error = nacl_secure_random_init();
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    if (error)
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        __throw_system_error(error, ("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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}
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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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    size_t n = sizeof(r);
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    size_t bytes_written;
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    int error = nacl_secure_random(&r, n, &bytes_written);
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    if (error != 0)
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        __throw_system_error(error, "random_device failed getting bytes");
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    else if (bytes_written != n)
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        __throw_runtime_error("random_device failed to obtain enough bytes");
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    return r;
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}
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#elif defined(_LIBCPP_USING_WIN32_RANDOM)
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random_device::random_device(const string& __token)
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{
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    if (__token != "/dev/urandom")
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        __throw_system_error(ENOENT, ("random device not supported " + __token).c_str());
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}
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random_device::~random_device()
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{
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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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    errno_t err = rand_s(&r);
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    if (err)
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        __throw_system_error(err, "random_device rand_s failed.");
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    return r;
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}
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#elif defined(_LIBCPP_USING_FUCHSIA_CPRNG)
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random_device::random_device(const string& __token) {
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  if (__token != "/dev/urandom")
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    __throw_system_error(ENOENT, ("random device not supported " + __token).c_str());
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}
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random_device::~random_device() {}
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unsigned random_device::operator()() {
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  // Implicitly link against the vDSO system call ABI without
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  // requiring the final link to specify -lzircon explicitly when
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  // statically linking libc++.
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#  pragma comment(lib, "zircon")
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  // The system call cannot fail.  It returns only when the bits are ready.
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  unsigned r;
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  _zx_cprng_draw(&r, sizeof(r));
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  return r;
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}
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#else
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#error "Random device not implemented for this architecture"
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#endif
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double
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random_device::entropy() const noexcept
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{
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#if defined(_LIBCPP_USING_DEV_RANDOM) && defined(RNDGETENTCNT)
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  int ent;
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  if (::ioctl(__f_, RNDGETENTCNT, &ent) < 0)
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    return 0;
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  if (ent < 0)
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    return 0;
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  if (ent > std::numeric_limits<result_type>::digits)
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    return std::numeric_limits<result_type>::digits;
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  return ent;
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#elif defined(_LIBCPP_USING_ARC4_RANDOM) || defined(_LIBCPP_USING_FUCHSIA_CPRNG)
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  return std::numeric_limits<result_type>::digits;
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#else
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  return 0;
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#endif
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0
}
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_LIBCPP_END_NAMESPACE_STD