Fixed bug 4097 - Segmentation fault by SDL_CreateThreadWithStackSize

Dongsun Kim Normal case 1. [thread 1] SDL_CreateThreadWithStackSize calls SDL_SYS_CreateThread. 2. [thread 1] If successful, it calls SDL_SemWait. 3. [thread 2] SDL_RunThread calls SDL_SYS_SetupThread, SDL_ThreadID, SDL_SemPost. 4. [thread 1] SDL_CreateThreadWithStackSize calls SDL_DestroySemaphore, SDL_free. Crash case (Segmentation fault) 1. [thread 1] SDL_CreateThreadWithStackSize calls SDL_SYS_CreateThread. 2. [thread 1] If successful, it calls SDL_SemWait. --> Error return due to SIGNAL(SYSTEM or Real Time) at sem_wait(pthread). 3. [thread 1] SDL_CreateThreadWithStackSize calls SDL_DestroySemaphore, SDL_free. 4. [thread 2] SDL_RunThread calls SDL_SYS_SetupThread, SDL_ThreadID, SDL_SemPost. --> Segmentation fault at strlen or sem_post.
libsdl-org · Feb 26, 2018 · f9f45d0 · f9f45d0
1 parent 5cbb90d
commit f9f45d0
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/src/thread/pthread/SDL_syssem.c b/src/thread/pthread/SDL_syssem.c
@@ -91,7 +91,10 @@ SDL_SemWait(SDL_sem * sem)
         return SDL_SetError("Passed a NULL semaphore");
     }
 
-    retval = sem_wait(&sem->sem);
+    do {
+        retval = sem_wait(&sem->sem);
+    } while (retval < 0 && errno == EINTR);
+
     if (retval < 0) {
         retval = SDL_SetError("sem_wait() failed");
     }