[require c++20] [moved to stduuid]

src/utils/utils.cpp

@@ -119,33 +119,15 @@ auto create_curl() -> CURL * {
 }
 
 auto create_uuid_string() -> std::string {
-#ifdef _WIN32
-  UUID guid{};
-  UuidCreate(&guid);
+  std::random_device random_device;
+  auto seed_data = std::array<int, std::mt19937::state_size>{};
+  std::generate(std::begin(seed_data), std::end(seed_data),
+                std::ref(random_device));
+  std::seed_seq seq(std::begin(seed_data), std::end(seed_data));
+  std::mt19937 generator(seq);
+  uuids::uuid_random_generator gen{generator};
 
-  unsigned char *s;
-  UuidToStringA(&guid, &s);
-
-  std::string ret(reinterpret_cast<char *>(s));
-  RpcStringFreeA(&s);
-
-  return ret;
-#else
-#if __linux__
-  uuid guid;
-  guid.make(UUID_MAKE_V4);
-  return guid.string();
-#else
-  uuid_t guid;
-  uuid_generate_random(guid);
-
-  std::string ret;
-  ret.resize(37);
-  uuid_unparse(guid, &ret[0]);
-
-  return ret.c_str();
-#endif
-#endif
+  return uuids::to_string(gen());
 }
 
 auto create_volume_label(const provider_type &prov) -> std::string {
@@ -220,23 +202,12 @@ auto get_attributes_from_meta(const api_meta_map &meta) -> DWORD {
 }
 
 auto get_environment_variable(const std::string &variable) -> std::string {
-#ifdef _WIN32
-  std::string val;
-  auto sz = ::GetEnvironmentVariable(&variable[0], nullptr, 0);
-  if (sz > 0) {
-    val.resize(sz);
-    ::GetEnvironmentVariable(&variable[0], &val[0], sz);
-  }
-
-  return value.c_str();
-#else
   static std::mutex mtx{};
   mutex_lock lock{mtx};
 
   const auto *val = std::getenv(variable.c_str());
   auto ret = std::string(val == nullptr ? "" : val);
   return ret;
-#endif
 }
 
 auto get_file_time_now() -> std::uint64_t {