xref: /llvm-project/libcxx/test/std/numerics/rand/rand.device/eval.pass.cpp (revision e8cfbfd05a951b85f80156dffc8eeecb34c7271c)
1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // UNSUPPORTED: no-random-device
10 
11 // <random>
12 
13 // class random_device;
14 
15 // result_type operator()();
16 
17 #include <random>
18 #include <cassert>
19 #include <string>
20 #include <system_error>
21 
22 #include "test_macros.h"
23 
main(int,char **)24 int main(int, char**)
25 {
26     {
27         std::random_device r;
28         std::random_device::result_type e = r();
29         ((void)e); // Prevent unused warning
30     }
31 
32     // When using the `/dev/urandom` implementation, make sure that we throw
33     // an exception when we hit EOF while reading the custom-provided file.
34 #if !defined(TEST_HAS_NO_EXCEPTIONS) && defined(_LIBCPP_USING_DEV_RANDOM)
35     {
36         std::random_device r("/dev/null");
37         try {
38             (void)r();
39             LIBCPP_ASSERT(false);
40         } catch (const std::system_error&) {
41         }
42     }
43 #endif
44 
45   return 0;
46 }
47