Cleanup

tests/render_snapshot.cpp

@@ -0,0 +1,88 @@
+#include <boost/test/unit_test.hpp>
+
+#include <array>
+#include <atomic>
+#include <barrier>
+#include <memory>
+#include <thread>
+
+#include "detail/render_snapshot.hpp"
+
+namespace {
+
+struct snapshot {
+  std::atomic<int>& live;
+  std::array<int, 64> samples{};
+  explicit snapshot(std::atomic<int>& count, int value = 0) : live(count) {
+    ++live;
+    samples.fill(value);
+  }
+  ~snapshot() { --live; }
+};
+
+}
+
+BOOST_AUTO_TEST_CASE(sonus_snapshots_are_reclaimed_without_rendering) {
+  auto live = std::atomic<int>{0};
+  auto state = sonus::detail::render_snapshot<snapshot>{};
+  for (auto index = 0; index < 1000; ++index) {
+    state.publish(std::make_unique<snapshot>(live, index));
+    BOOST_TEST(live.load() == 1);
+  }
+  state.publish(nullptr);
+  BOOST_TEST(live.load() == 0);
+}
+
+BOOST_AUTO_TEST_CASE(sonus_snapshots_outlive_readers_and_are_collected_on_control_thread) {
+  auto live = std::atomic<int>{0};
+  auto state = sonus::detail::render_snapshot<snapshot>{};
+  state.publish(std::make_unique<snapshot>(live, 42));
+  {
+    auto first = state.read();
+    state.publish(std::make_unique<snapshot>(live, 43));
+    {
+      auto second = state.read();
+      state.publish(std::make_unique<snapshot>(live, 44));
+      state.collect();
+      BOOST_TEST(live.load() == 3);
+      BOOST_TEST(second.get()->samples.front() == 43);
+    }
+    state.collect();
+    BOOST_TEST(live.load() == 3);
+    BOOST_TEST(first.get()->samples.back() == 42);
+  }
+  BOOST_TEST(live.load() == 3);
+  state.collect();
+  BOOST_TEST(live.load() == 1);
+}
+
+BOOST_AUTO_TEST_CASE(sonus_snapshot_publication_overlaps_readers) {
+  auto live = std::atomic<int>{0};
+  auto state = sonus::detail::render_snapshot<snapshot>{};
+  state.publish(std::make_unique<snapshot>(live));
+  auto start = std::barrier{3};
+  auto failed = std::atomic<bool>{false};
+  auto reader = [&] {
+    start.arrive_and_wait();
+    for (auto index = 0; index < 20000; ++index) {
+      auto guard = state.read();
+      auto const* value = guard.get();
+      for (auto sample : value->samples) {
+        if (sample != value->samples.front()) {
+          failed.store(true);
+        }
+      }
+    }
+  };
+  auto first = std::thread{reader};
+  auto second = std::thread{reader};
+  start.arrive_and_wait();
+  for (auto index = 0; index < 20000; ++index) {
+    state.publish(std::make_unique<snapshot>(live, index));
+  }
+  first.join();
+  second.join();
+  state.collect();
+  BOOST_TEST(!failed.load());
+  BOOST_TEST(live.load() == 1);
+}