1 files changed, 62 insertions, 0 deletions
diff --git a/source/kit/mersenne_twister_64.c b/source/kit/mersenne_twister_64.c
new file mode 100644
index 0000000..4be4313
--- /dev/null
+++ b/source/kit/mersenne_twister_64.c
@@ -0,0 +1,62 @@
+#include "mersenne_twister_64.h"
+
+#include <time.h>
+
+void kit_mt64_init(kit_mt64_state_t *state, uint64_t seed) {
+  state->mt[0] = seed;
+  for (state->index = 1; state->index < KIT_MT64_N; state->index++)
+    state->mt[state->index] = (6364136223846793005ull *
+                                   (state->mt[state->index - 1] ^
+                                    (state->mt[state->index - 1] >>
+                                     62u)) +
+                               state->index);
+}
+
+uint64_t kit_mt64_generate(kit_mt64_state_t *state) {
+  static uint64_t const mag01[2] = { 0ull, 0xB5026F5AA96619E9ull };
+
+  int      i;
+  uint64_t x;
+
+  if (state->index >= KIT_MT64_N) {
+    for (i = 0; i < KIT_MT64_N - 156; i++) {
+      x = (state->mt[i] & 0xFFFFFFFF80000000ull) |
+          (state->mt[i + 1] & 0x7FFFFFFFull);
+      state->mt[i] = state->mt[i + 156] ^ (x >> 1u) ^
+                     mag01[(int) (x & 1ull)];
+    }
+
+    for (; i < KIT_MT64_N - 1; i++) {
+      x = (state->mt[i] & 0xFFFFFFFF80000000ull) |
+          (state->mt[i + 1] & 0x7FFFFFFFull);
+      state->mt[i] = state->mt[i + (156 - KIT_MT64_N)] ^ (x >> 1u) ^
+                     mag01[(int) (x & 1ull)];
+    }
+
+    x = (state->mt[KIT_MT64_N - 1] & 0xFFFFFFFF80000000ull) |
+        (state->mt[0] & 0x7FFFFFFFull);
+    state->mt[KIT_MT64_N - 1] = state->mt[156 - 1] ^ (x >> 1u) ^
+                                mag01[(int) (x & 1ull)];
+
+    state->index = 0;
+  }
+
+  x = state->mt[state->index++];
+
+  x ^= (x >> 29u) & 0x5555555555555555ull;
+  x ^= (x << 17u) & 0x71D67FFFEDA60000ull;
+  x ^= (x << 37u) & 0xFFF7EEE000000000ull;
+  x ^= (x >> 43u);
+
+  return x;
+}
+
+uint64_t kit_mt64_seed() {
+  struct timespec t;
+  timespec_get(&t, TIME_UTC);
+
+  kit_mt64_state_t s;
+  kit_mt64_init(&s, (uint64_t) t.tv_nsec);
+
+  return kit_mt64_generate(&s);
+}