Function mi_random_init_ex

3rd/mimalloc-2.0.9/src/random.c:323–342

}

static void mi_random_init_ex(mi_random_ctx_t* ctx, bool use_weak) {
  uint8_t key[32];
  if (use_weak || !os_random_buf(key, sizeof(key))) {
    // if we fail to get random data from the OS, we fall back to a
    // weak random source based on the current time
    #if !defined(__wasi__)
    if (!use_weak) { _mi_warning_message("unable to use secure randomness\n"); }
    #endif
    uintptr_t x = _mi_os_random_weak(0);
    for (size_t i = 0; i < 8; i++) {  // key is eight 32-bit words.
      x = _mi_random_shuffle(x);
      ((uint32_t*)key)[i] = (uint32_t)x;
    }
    ctx->weak = true;
  }
  else {
    ctx->weak = false;
  }
  chacha_init(ctx, key, (uintptr_t)ctx /*nonce*/ );
}

void _mi_random_init(mi_random_ctx_t* ctx) {
  mi_random_init_ex(ctx, false);