Line data    Source code

       1             : // Copyright (c) 2023 The Bitcoin Core developers
       2             : // Distributed under the MIT software license, see the accompanying
       3             : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       4             : 
       5             : #include <test/util/random.h>
       6             : 
       7             : #include <logging.h>
       8             : #include <random.h>
       9             : #include <uint256.h>
      10             : 
      11             : #include <cstdlib>
      12             : #include <string>
      13             : 
      14           2 : FastRandomContext g_insecure_rand_ctx;
      15             : 
      16             : /** Return the unsigned from the environment var if available, otherwise 0 */
      17           1 : static uint256 GetUintFromEnv(const std::string& env_name)
      18             : {
      19           1 :     const char* num = std::getenv(env_name.c_str());
      20           1 :     if (!num) return {};
      21           0 :     return uint256S(num);
      22           1 : }
      23             : 
      24           1 : void Seed(FastRandomContext& ctx)
      25             : {
      26             :     // Should be enough to get the seed once for the process
      27             :     static uint256 seed{};
      28           1 :     static const std::string RANDOM_CTX_SEED{"RANDOM_CTX_SEED"};
      29           1 :     if (seed.IsNull()) seed = GetUintFromEnv(RANDOM_CTX_SEED);
      30           1 :     if (seed.IsNull()) seed = GetRandHash();
      31           1 :     LogPrintf("%s: Setting random seed for current tests to %s=%s\n", __func__, RANDOM_CTX_SEED, seed.GetHex());
      32           1 :     ctx = FastRandomContext(seed);
      33           1 : }