Adding a check to not wait if the thread has already fully started. (#228)

When starting the depth engine, only wait on the condition if we don't think the thread has started yet as it will never be released if the thread has already triggered the condition.

src/dewrapper/dewrapper.c

@@ -32,6 +32,7 @@ typedef struct _dewrapper_context_t
     THREAD_HANDLE thread;
     LOCK_HANDLE lock;
     COND_HANDLE condition;
+    volatile bool thread_started;
     volatile bool thread_stop;
     k4a_result_t thread_start_result;
 
@@ -191,6 +192,7 @@ static int depth_engine_thread(void *param)
     // The Start routine is blocked waiting for this thread to complete startup, so we signal it here and share our
     // startup status.
     Lock(dewrapper->lock);
+    dewrapper->thread_started = true;
     dewrapper->thread_start_result = result;
     Condition_Post(dewrapper->condition);
     Unlock(dewrapper->lock);
@@ -519,6 +521,7 @@ k4a_result_t dewrapper_start(dewrapper_t dewrapper_handle,
         dewrapper->fps = config->camera_fps;
         dewrapper->depth_mode = config->depth_mode;
         dewrapper->thread_stop = false;
+        dewrapper->thread_started = false;
 
         THREADAPI_RESULT tresult = ThreadAPI_Create(&dewrapper->thread, depth_engine_thread, dewrapper);
         result = K4A_RESULT_FROM_BOOL(tresult == THREADAPI_OK);
@@ -527,9 +530,12 @@ k4a_result_t dewrapper_start(dewrapper_t dewrapper_handle,
         {
             Lock(dewrapper->lock);
             locked = true;
-            int infinite_timeout = 0;
-            COND_RESULT cond_result = Condition_Wait(dewrapper->condition, dewrapper->lock, infinite_timeout);
-            result = K4A_RESULT_FROM_BOOL(cond_result == COND_OK);
+            if (!dewrapper->thread_started)
+            {
+                int infinite_timeout = 0;
+                COND_RESULT cond_result = Condition_Wait(dewrapper->condition, dewrapper->lock, infinite_timeout);
+                result = K4A_RESULT_FROM_BOOL(cond_result == COND_OK);
+            }
         }
 
         if (K4A_SUCCEEDED(result) && K4A_FAILED(dewrapper->thread_start_result))