diff options
Diffstat (limited to 'contrib/libc++/src/random.cpp')
-rw-r--r-- | contrib/libc++/src/random.cpp | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/contrib/libc++/src/random.cpp b/contrib/libc++/src/random.cpp new file mode 100644 index 0000000..4ab424e --- /dev/null +++ b/contrib/libc++/src/random.cpp @@ -0,0 +1,152 @@ +//===-------------------------- random.cpp --------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is dual licensed under the MIT and the University of Illinois Open +// Source Licenses. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#if defined(_LIBCPP_USING_WIN32_RANDOM) +// Must be defined before including stdlib.h to enable rand_s(). +#define _CRT_RAND_S +#endif // defined(_LIBCPP_USING_WIN32_RANDOM) + +#include "random" +#include "system_error" + +#if defined(__sun__) +#define rename solaris_headers_are_broken +#endif // defined(__sun__) + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> + +#if defined(_LIBCPP_USING_DEV_RANDOM) +#include <fcntl.h> +#include <unistd.h> +#elif defined(_LIBCPP_USING_NACL_RANDOM) +#include <nacl/nacl_random.h> +#endif + + +_LIBCPP_BEGIN_NAMESPACE_STD + +#if defined(_LIBCPP_USING_ARC4_RANDOM) + +random_device::random_device(const string& __token) +{ + if (__token != "/dev/urandom") + __throw_system_error(ENOENT, ("random device not supported " + __token).c_str()); +} + +random_device::~random_device() +{ +} + +unsigned +random_device::operator()() +{ + return arc4random(); +} + +#elif defined(_LIBCPP_USING_DEV_RANDOM) + +random_device::random_device(const string& __token) + : __f_(open(__token.c_str(), O_RDONLY)) +{ + if (__f_ < 0) + __throw_system_error(errno, ("random_device failed to open " + __token).c_str()); +} + +random_device::~random_device() +{ + close(__f_); +} + +unsigned +random_device::operator()() +{ + unsigned r; + size_t n = sizeof(r); + char* p = reinterpret_cast<char*>(&r); + while (n > 0) + { + ssize_t s = read(__f_, p, n); + if (s == 0) + __throw_system_error(ENODATA, "random_device got EOF"); + if (s == -1) + { + if (errno != EINTR) + __throw_system_error(errno, "random_device got an unexpected error"); + continue; + } + n -= static_cast<size_t>(s); + p += static_cast<size_t>(s); + } + return r; +} + +#elif defined(_LIBCPP_USING_NACL_RANDOM) + +random_device::random_device(const string& __token) +{ + if (__token != "/dev/urandom") + __throw_system_error(ENOENT, ("random device not supported " + __token).c_str()); + int error = nacl_secure_random_init(); + if (error) + __throw_system_error(error, ("random device failed to open " + __token).c_str()); +} + +random_device::~random_device() +{ +} + +unsigned +random_device::operator()() +{ + unsigned r; + size_t n = sizeof(r); + size_t bytes_written; + int error = nacl_secure_random(&r, n, &bytes_written); + if (error != 0) + __throw_system_error(error, "random_device failed getting bytes"); + else if (bytes_written != n) + __throw_runtime_error("random_device failed to obtain enough bytes"); + return r; +} + +#elif defined(_LIBCPP_USING_WIN32_RANDOM) + +random_device::random_device(const string& __token) +{ + if (__token != "/dev/urandom") + __throw_system_error(ENOENT, ("random device not supported " + __token).c_str()); +} + +random_device::~random_device() +{ +} + +unsigned +random_device::operator()() +{ + unsigned r; + errno_t err = rand_s(&r); + if (err) + __throw_system_error(err, "random_device rand_s failed."); + return r; +} + +#else +#error "Random device not implemented for this architecture" +#endif + +double +random_device::entropy() const _NOEXCEPT +{ + return 0; +} + +_LIBCPP_END_NAMESPACE_STD |