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test time gen only on Windows

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This commit is contained in:
Marius Bancila 2019-05-17 15:55:43 +03:00
parent b74a5eb7e9
commit 7bd86a11e3
2 changed files with 12 additions and 11 deletions
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19
include/uuid.h
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@ -14,6 +14,7 @@
#include <optional> #include <optional>
#include <chrono> #include <chrono>
#include <numeric> #include <numeric>
#include <atomic>
#include <gsl/span> #include <gsl/span>
#ifdef _WIN32 #ifdef _WIN32
@ -242,6 +243,10 @@ namespace uuids
size_t m_blockByteIndex; size_t m_blockByteIndex;
size_t m_byteCount; size_t m_byteCount;
}; };
static std::mt19937 clock_gen(std::random_device{}());
static std::uniform_int_distribution<short> clock_dis{ -32768, 32767 };
static std::atomic_short clock_sequence = clock_dis(clock_gen);
} }
// -------------------------------------------------------------------------------------------------------------------------- // --------------------------------------------------------------------------------------------------------------------------
@ -805,14 +810,13 @@ namespace uuids
detail::sha1 hasher; detail::sha1 hasher;
}; };
// this implementation is currently unreliable for good uuids // !!! DO NOT USE THIS IN PRODUCTION
// this implementation is unreliable for good uuids
class uuid_time_generator class uuid_time_generator
{ {
using mac_address = std::array<unsigned char, 6>; using mac_address = std::array<unsigned char, 6>;
std::optional<mac_address> device_address; std::optional<mac_address> device_address;
std::mt19937 generator;
std::uniform_int_distribution<short> dis;
bool get_mac_address() bool get_mac_address()
{ {
@ -846,13 +850,8 @@ namespace uuids
} }
public: public:
uuid_time_generator():dis(-32768, 32767) uuid_time_generator()
{ {
std::random_device rd;
auto seed_data = std::array<int, std::mt19937::state_size> {};
std::generate(std::begin(seed_data), std::end(seed_data), std::ref(rd));
std::seed_seq seq(std::begin(seed_data), std::end(seed_data));
generator.seed(seq);
} }
uuid operator()() uuid operator()()
@ -863,7 +862,7 @@ namespace uuids
auto tm = get_time_intervals(); auto tm = get_time_intervals();
short clock_seq = dis(generator); short clock_seq = detail::clock_sequence++;
clock_seq &= 0x3FFF; clock_seq &= 0x3FFF;

2
test/test_generators.cpp
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@ -220,6 +220,7 @@ TEST_CASE("Test name generator (std::string)", "[gen][name]")
REQUIRE(id3 != id4); REQUIRE(id3 != id4);
} }
#ifdef _WIN32
TEST_CASE("Test time generator", "[gen][time]") TEST_CASE("Test time generator", "[gen][time]")
{ {
uuid_time_generator gen; uuid_time_generator gen;
@ -241,3 +242,4 @@ TEST_CASE("Test time generator", "[gen][time]")
REQUIRE(ids.size() == 100); REQUIRE(ids.size() == 100);
} }
#endif