esphome/tests/integration/fixtures/host_logger_thread_safety.yaml

esphome:
  name: host-logger-thread-test
host:
api:
logger:

button:
  - platform: template
    name: "Start Thread Race Test"
    id: start_test_button
    on_press:
      - lambda: |-
          // Number of threads and messages per thread
          static const int NUM_THREADS = 3;
          static const int MESSAGES_PER_THREAD = 100;

          // Counters
          static std::atomic<int> total_messages_logged{0};

          // Thread function - must be a regular function pointer for pthread
          struct ThreadTest {
            static void *thread_func(void *arg) {
              int thread_id = *static_cast<int *>(arg);

              // Set thread name (different signatures on macOS vs Linux)
              char thread_name[16];
              snprintf(thread_name, sizeof(thread_name), "LogThread%d", thread_id);
              #ifdef __APPLE__
              pthread_setname_np(thread_name);
              #else
              pthread_setname_np(pthread_self(), thread_name);
              #endif

              // Log messages with different log levels
              for (int i = 0; i < MESSAGES_PER_THREAD; i++) {
                switch (i % 4) {
                  case 0:
                    ESP_LOGI("thread_test", "THREAD%d_MSG%03d_INFO_MESSAGE_WITH_DATA_%08X",
                             thread_id, i, i * 12345);
                    break;
                  case 1:
                    ESP_LOGD("thread_test", "THREAD%d_MSG%03d_DEBUG_MESSAGE_WITH_DATA_%08X",
                             thread_id, i, i * 12345);
                    break;
                  case 2:
                    ESP_LOGW("thread_test", "THREAD%d_MSG%03d_WARN_MESSAGE_WITH_DATA_%08X",
                             thread_id, i, i * 12345);
                    break;
                  case 3:
                    ESP_LOGE("thread_test", "THREAD%d_MSG%03d_ERROR_MESSAGE_WITH_DATA_%08X",
                             thread_id, i, i * 12345);
                    break;
                }
                total_messages_logged.fetch_add(1, std::memory_order_relaxed);

                // Small busy loop to vary timing between threads
                int delay_count = (thread_id + 1) * 10;
                while (delay_count-- > 0) {
                  asm volatile("" ::: "memory");  // Prevent optimization
                }
              }
              return nullptr;
            }
          };

          ESP_LOGI("thread_test", "RACE_TEST_START: Starting %d threads with %d messages each",
                   NUM_THREADS, MESSAGES_PER_THREAD);

          // Reset counter for this test run
          total_messages_logged.store(0, std::memory_order_relaxed);

          pthread_t threads[NUM_THREADS];
          int thread_ids[NUM_THREADS];

          // Create all threads
          for (int i = 0; i < NUM_THREADS; i++) {
            thread_ids[i] = i;
            int ret = pthread_create(&threads[i], nullptr, ThreadTest::thread_func, &thread_ids[i]);
            if (ret != 0) {
              ESP_LOGE("thread_test", "RACE_TEST_ERROR: Failed to create thread %d", i);
              return;
            }
          }

          // Wait for all threads to complete
          for (int i = 0; i < NUM_THREADS; i++) {
            pthread_join(threads[i], nullptr);
          }

          ESP_LOGI("thread_test", "RACE_TEST_COMPLETE: All threads finished, total messages: %d",
                   total_messages_logged.load(std::memory_order_relaxed));