3 // Copyright (C) 2012-2017 Free Software Foundation, Inc.
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
25 #define _GLIBCXX_USE_CXX11_ABI 1
28 #ifdef _GLIBCXX_USE_C99_STDINT_TR1
30 #if defined __i386__ || defined __x86_64__
37 #ifdef _GLIBCXX_HAVE_UNISTD_H
41 #ifdef _GLIBCXX_HAVE_SYS_IOCTL_H
42 # include <sys/ioctl.h>
45 #ifdef _GLIBCXX_HAVE_LINUX_RANDOM_H
46 # include <linux/random.h>
49 namespace std
_GLIBCXX_VISIBILITY(default)
54 _M_strtoul(const std::string
& __str
)
56 unsigned long __ret
= 5489UL;
57 if (__str
!= "mt19937")
59 const char* __nptr
= __str
.c_str();
61 __ret
= std::strtoul(__nptr
, &__endptr
, 0);
62 if (*__nptr
== '\0' || *__endptr
!= '\0')
63 std::__throw_runtime_error(__N("random_device::_M_strtoul"
64 "(const std::string&)"));
69 #if (defined __i386__ || defined __x86_64__) && defined _GLIBCXX_X86_RDRAND
71 __attribute__ ((target("rdrnd")))
74 unsigned int retries
= 100;
77 while (__builtin_ia32_rdrand32_step(&val
) == 0)
79 std::__throw_runtime_error(__N("random_device::__x86_rdrand(void)"));
87 random_device::_M_init(const std::string
& token
)
89 const char *fname
= token
.c_str();
91 if (token
== "default")
93 #if (defined __i386__ || defined __x86_64__) && defined _GLIBCXX_X86_RDRAND
94 unsigned int eax
, ebx
, ecx
, edx
;
95 // Check availability of cpuid and, for now at least, also the
96 // CPU signature for Intel's
97 if (__get_cpuid_max(0, &ebx
) > 0 && ebx
== signature_INTEL_ebx
)
99 __cpuid(1, eax
, ebx
, ecx
, edx
);
108 fname
= "/dev/urandom";
110 else if (token
!= "/dev/urandom" && token
!= "/dev/random")
112 std::__throw_runtime_error(__N("random_device::"
113 "random_device(const std::string&)"));
115 _M_file
= static_cast<void*>(std::fopen(fname
, "rb"));
121 random_device::_M_init_pretr1(const std::string
& token
)
123 _M_mt
.seed(_M_strtoul(token
));
127 random_device::_M_fini()
130 std::fclose(static_cast<FILE*>(_M_file
));
133 random_device::result_type
134 random_device::_M_getval()
136 #if (defined __i386__ || defined __x86_64__) && defined _GLIBCXX_X86_RDRAND
138 return __x86_rdrand();
143 size_t n
= sizeof(result_type
);
144 #ifdef _GLIBCXX_HAVE_UNISTD_H
147 const int e
= read(fileno(static_cast<FILE*>(_M_file
)), p
, n
);
151 p
= static_cast<char*>(p
) + e
;
153 else if (e
!= -1 || errno
!= EINTR
)
154 __throw_runtime_error(__N("random_device could not be read"));
158 const size_t e
= std::fread(p
, n
, 1, static_cast<FILE*>(_M_file
));
160 __throw_runtime_error(__N("random_device could not be read"));
166 random_device::result_type
167 random_device::_M_getval_pretr1()
173 random_device::_M_getentropy() const noexcept
175 #if defined _GLIBCXX_HAVE_SYS_IOCTL_H && defined RNDGETENTCNT
179 const int fd
= fileno(static_cast<FILE*>(_M_file
));
184 if (ioctl(fd
, RNDGETENTCNT
, &ent
) < 0)
190 const int max
= sizeof(result_type
) * __CHAR_BIT__
;
194 return static_cast<double>(ent
);
200 template class mersenne_twister_engine
<
206 0xefc60000UL
, 18, 1812433253UL>;