t/rng-test.c

   1 /*
   2  * Simple random number generator for testing.
   3  * Copyright © 2022-2023 Nick Bowler
   4  *
   5  * Directly compare the test lib RNG against the reference implementation.
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <config.h>
  22 #include "tap.h"
  23
  24 #include "rng.c"
  25 #include "xos256p.c"
  26
  27 int main(void)
  28 {
  29         unsigned long long seed_state = 0xdeadbeeff00dcafe;
  30         unsigned long long test_result, ref_result;
  31         unsigned long long ref_state[4], test_state[4];
  32         int i, ret = 0;
  33
  34         tap_plan(200);
  35         for (i = 0; i < 100; i++) {
  36                 s[0] = ref_state[0] = test_state[0] = splitmix64(&seed_state);
  37                 s[1] = ref_state[1] = test_state[1] = splitmix64(&seed_state);
  38                 s[2] = ref_state[2] = test_state[2] = splitmix64(&seed_state);
  39                 s[3] = ref_state[3] = test_state[3] = splitmix64(&seed_state);
  40
  41                 ref_result = next();
  42                 test_result = xoshiro256p(test_state);
  43
  44                 if (!tap_result(ref_result == test_result, "rng output")) {
  45                         tap_diag("Failed, unexpected result");
  46                         tap_diag("   with initial state %llx %llx %llx %llx",
  47                                                   ref_state[0], ref_state[1],
  48                                                   ref_state[2], ref_state[3]);
  49                         tap_diag("   received: %llx", test_result);
  50                         tap_diag("   expected: %llx", ref_result);
  51                 }
  52
  53                 if (!tap_result(s[0] == test_state[0] && s[1] == test_state[1]
  54                              && s[2] == test_state[2] && s[3] == test_state[3],
  55                                 "rng state update"))
  56                 {
  57                         tap_diag("Failed, state update differed");
  58                         tap_diag("   with initial state %llx %llx %llx %llx",
  59                                                   ref_state[0], ref_state[1],
  60                                                   ref_state[2], ref_state[3]);
  61                         tap_diag("   received: %llx %llx %llx %llx",
  62                                        test_state[0], test_state[1],
  63                                        test_state[2], test_state[3]);
  64                         tap_diag("   expected: %llx %llx %llx %llx",
  65                                        (unsigned long long)s[0],
  66                                        (unsigned long long)s[1],
  67                                        (unsigned long long)s[2],
  68                                        (unsigned long long)s[3]);
  69                 }
  70         }
  71
  72         tap_done();
  73 }