fix(sync): Destroy condition variables

CHANGELOG.md

@@ -14,6 +14,7 @@
 
 - Native: store daemon logs, minidumps, crash envelopes, and scratch files in `.run` directories so they are cleaned up with the run instead of accumulating in the database root. Minidumps can still be retained with `cache_keep`, which stores `.dmp` sidecars alongside cached envelopes. ([#1976](https://github.com/getsentry/sentry-native/pull/1976))
 - Linux/ARM32: prevent recursive crashes when libunwind receives an unmapped initial instruction pointer during crash handling. ([#1977](https://github.com/getsentry/sentry-native/pull/1977))
+- Destroy condition variables as approriate when no longer needed. ([#2004](https://github.com/getsentry/sentry-native/pull/2004))
 
 ## 0.16.3
 

src/sentry_app_hang_monitor.c

@@ -140,6 +140,7 @@ sentry__app_hang_monitor_start(const sentry_options_t *options)
     sentry__app_hang_set_active(true);
     if (sentry__thread_spawn(&g_thread, worker, NULL) != 0) {
         sentry__app_hang_set_active(false);
+        sentry__cond_free(&g_wait_cond);
         SENTRY_WARN("app-hang: failed to spawn watchdog thread");
         return 1;
     }
@@ -161,6 +162,7 @@ sentry__app_hang_monitor_stop(void)
     sentry__mutex_unlock(&g_wait_mutex);
     sentry__thread_join(g_thread);
     sentry__thread_free(&g_thread);
+    sentry__cond_free(&g_wait_cond);
     sentry__app_hang_latch_reset();
     g_running = false;
     // g_timeout_ms are intentionally NOT cleared here: the worker

src/sentry_sync.c

@@ -450,6 +450,8 @@ sentry__threadpool_free(sentry_threadpool_t *pool)
         sentry__thread_free(&pool->threads[i]);
     }
     sentry_free(pool->thread_name);
+    sentry__cond_free(&pool->work_signal);
+    sentry__cond_free(&pool->state_signal);
     sentry__mutex_free(&pool->lock);
     sentry_free(pool->threads);
     sentry_free(pool);
@@ -571,6 +573,8 @@ sentry__bgworker_decref(sentry_bgworker_t *bgw)
         bgw->free_state(bgw->state);
     }
     sentry__thread_free(&bgw->thread_id);
+    sentry__cond_free(&bgw->submit_signal);
+    sentry__cond_free(&bgw->done_signal);
     sentry__mutex_free(&bgw->task_lock);
     sentry_free(bgw->thread_name);
     sentry_free(bgw);
@@ -708,6 +712,7 @@ static void
 sentry__flush_task_decref(sentry_flush_task_t *task)
 {
     if (sentry__atomic_fetch_and_add(&task->refcount, -1) == 1) {
+        sentry__cond_free(&task->signal);
         sentry__mutex_free(&task->lock);
         sentry_free(task);
     }

src/sentry_sync.h

@@ -93,6 +93,13 @@ InitializeConditionVariable_PREVISTA(
     ConditionVariable->ContinueEvent = CreateEventW(NULL, FALSE, FALSE, NULL);
 }
 
+inline void
+DeleteConditionVariable_PREVISTA(PCONDITION_VARIABLE_PREVISTA ConditionVariable)
+{
+    CloseHandle(ConditionVariable->Semaphore);
+    CloseHandle(ConditionVariable->ContinueEvent);
+}
+
 inline BOOL
 SleepConditionVariableCS_PREVISTA(
     PCONDITION_VARIABLE_PREVISTA cv, PCRITICAL_SECTION cs, DWORD timeout)
@@ -210,6 +217,8 @@ typedef struct sentry__winmutex_s sentry_mutex_t;
 typedef CONDITION_VARIABLE_PREVISTA sentry_cond_t;
 #        define sentry__cond_init(CondVar)                                     \
             InitializeConditionVariable_PREVISTA(CondVar)
+#        define sentry__cond_free(CondVar)                                     \
+            DeleteConditionVariable_PREVISTA(CondVar)
 #        define sentry__cond_wake WakeConditionVariable_PREVISTA
 #        define sentry__cond_wake_all WakeAllConditionVariable_PREVISTA
 #        define sentry__cond_wait_timeout(CondVar, Lock, Timeout)              \
@@ -218,6 +227,7 @@ typedef CONDITION_VARIABLE_PREVISTA sentry_cond_t;
 #    else
 typedef CONDITION_VARIABLE sentry_cond_t;
 #        define sentry__cond_init(CondVar) InitializeConditionVariable(CondVar)
+#        define sentry__cond_free(CondVar) ((void)(CondVar))
 #        define sentry__cond_wake WakeConditionVariable
 #        define sentry__cond_wake_all WakeAllConditionVariable
 #        define sentry__cond_wait_timeout(CondVar, Lock, Timeout)              \
@@ -355,6 +365,7 @@ typedef pthread_cond_t sentry_cond_t;
             sentry_cond_t tmp = PTHREAD_COND_INITIALIZER;                      \
             *(CondVar) = tmp;                                                  \
         } while (0)
+#    define sentry__cond_free(CondVar) pthread_cond_destroy(CondVar)
 #    define sentry__cond_wait(Cond, Mutex)                                     \
         do {                                                                   \
             if (sentry__block_for_signal_handler()) {                          \

tests/unit/test_sync.c

@@ -68,8 +68,8 @@ trailing_task(void *data, void *UNUSED(state))
     sentry__mutex_lock(&executed_lock);
     bool *executed = (bool *)data;
     *executed = true;
-    sentry__mutex_unlock(&executed_lock);
     sentry__cond_wake(&trailing_task_done);
+    sentry__mutex_unlock(&executed_lock);
 }
 
 static bool
@@ -140,6 +140,8 @@ SENTRY_TEST(task_queue)
     sentry__mutex_lock(&executed_lock);
     sentry__cond_wait_timeout(&trailing_task_done, &executed_lock, 1000);
     TEST_CHECK(executed_after_shutdown);
+    sentry__cond_free(&trailing_task_done);
+    sentry__mutex_unlock(&executed_lock);
 }
 
 SENTRY_TEST(bgworker_flush)
@@ -361,6 +363,7 @@ SENTRY_TEST(bgworker_delayed_priority)
     TEST_CHECK_INT_EQUAL(os.order[1], 2); // immediate (submitted later)
 
     sentry__bgworker_decref(bgw);
+    sentry__cond_free(&blocker_signal);
 }
 
 static void
@@ -411,6 +414,7 @@ SENTRY_TEST(bgworker_delayed_current)
     TEST_CHECK_INT_EQUAL(os.order[1], 2);
 
     sentry__bgworker_decref(bgw);
+    sentry__cond_free(&blocker_signal);
 }
 
 SENTRY_TEST(bgworker_delayed_head)
@@ -481,6 +485,7 @@ SENTRY_TEST(bgworker_delayed_drop_current)
     TEST_CHECK_INT_EQUAL(os.order[2], 2);
 
     sentry__bgworker_decref(bgw);
+    sentry__cond_free(&blocker_signal);
 }
 
 SENTRY_TEST(bgworker_delayed_drop_next)
@@ -523,6 +528,7 @@ SENTRY_TEST(bgworker_delayed_drop_next)
     TEST_CHECK_INT_EQUAL(os.order[2], 3);
 
     sentry__bgworker_decref(bgw);
+    sentry__cond_free(&blocker_signal);
 }
 
 SENTRY_TEST(bgworker_delayed_cleanup)
@@ -735,10 +741,8 @@ SENTRY_TEST(threadpool_flush_wakes_all)
     sentry__threadpool_free(pool);
 
     TEST_CHECK(woke_all);
-#ifndef SENTRY_PLATFORM_WINDOWS
-    pthread_cond_destroy(&flush_state.cond);
-    pthread_cond_destroy(&task_state.cond);
-#endif
+    sentry__cond_free(&flush_state.cond);
+    sentry__cond_free(&task_state.cond);
     sentry__mutex_free(&flush_state.lock);
     sentry__mutex_free(&task_state.lock);
 }
@@ -772,9 +776,7 @@ SENTRY_TEST(threadpool_ordered_parallel)
 
     sentry__threadpool_shutdown(pool);
     sentry__threadpool_free(pool);
-#ifndef SENTRY_PLATFORM_WINDOWS
-    pthread_cond_destroy(&state.cond);
-#endif
+    sentry__cond_free(&state.cond);
     sentry__mutex_free(&state.lock);
 }
 
@@ -943,9 +945,7 @@ SENTRY_TEST(threadpool_max_pending)
 
     sentry__threadpool_shutdown(pool);
     sentry__threadpool_free(pool);
-#ifndef SENTRY_PLATFORM_WINDOWS
-    pthread_cond_destroy(&state.cond);
-#endif
+    sentry__cond_free(&state.cond);
     sentry__mutex_free(&state.lock);
 }
 
@@ -1056,9 +1056,7 @@ SENTRY_TEST(threadpool_commit_reentry)
 
     sentry__threadpool_shutdown(pool);
     sentry__threadpool_free(pool);
-#ifndef SENTRY_PLATFORM_WINDOWS
-    pthread_cond_destroy(&state.cond);
-#endif
+    sentry__cond_free(&state.cond);
     sentry__mutex_free(&state.lock);
 }
 
@@ -1327,10 +1325,8 @@ SENTRY_TEST(cond_wake_all)
     TEST_CHECK_INT_EQUAL(
         sentry__atomic_fetch(&state.woke), COND_WAKE_ALL_THREADS);
 
-#ifndef SENTRY_PLATFORM_WINDOWS
-    pthread_cond_destroy(&state.ready_cond);
-    pthread_cond_destroy(&state.waiting_cond);
-#endif
+    sentry__cond_free(&state.ready_cond);
+    sentry__cond_free(&state.waiting_cond);
     sentry__mutex_free(&state.mutex);
 }
 
@@ -1353,7 +1349,7 @@ SENTRY_TEST(cond_wait_timeout_overflow)
     sentry__mutex_unlock(&mutex);
 
     sentry__mutex_free(&mutex);
-    pthread_cond_destroy(&cond);
+    sentry__cond_free(&cond);
 #endif
 }