attempt to fix image preload thread bugs 1: module refcount.

image preload will use modules from threads, there is a possibility to
crash due wrong reference counting.

actually much more can fail, we need to check modules don't keep that
needs exclusive access in globals or per-Evas_Module, but that's
another issue.

TODO: replace spinlocks with atomic operations.



SVN revision: 38309

legacy/evas/src/lib/file/evas_module.c

@@ -174,6 +174,9 @@ evas_module_init(void)
 		  em->handle = NULL;
 		  em->data = NULL;
                   em->loaded = 0;
+#if defined(HAVE_PTHREAD_H) && defined(BUILD_ASYNC_PRELOAD)
+		  pthread_spin_init(&em->lock, PTHREAD_PROCESS_PRIVATE);
+#endif
 		  if (em->type == EVAS_MODULE_TYPE_ENGINE)
 		    {
 		       Evas_Module_Engine *eme;
@@ -306,20 +309,35 @@ evas_module_unload(Evas_Module *em)
    em->func.close = NULL;
    em->api = NULL;
    em->loaded = 0;
+#if defined(HAVE_PTHREAD_H) && defined(BUILD_ASYNC_PRELOAD)
+   pthread_spin_destroy(&em->lock);
+#endif
 }
 
 void
 evas_module_ref(Evas_Module *em)
 {
+#if defined(HAVE_PTHREAD_H) && defined(BUILD_ASYNC_PRELOAD)
+   pthread_spin_lock(&em->lock);
+#endif
    em->ref++;
 /*   printf("M: %s ref++ = %i\n", em->name, em->ref); */
+#if defined(HAVE_PTHREAD_H) && defined(BUILD_ASYNC_PRELOAD)
+   pthread_spin_unlock(&em->lock);
+#endif
 }
 
 void
 evas_module_unref(Evas_Module *em)
 {
+#if defined(HAVE_PTHREAD_H) && defined(BUILD_ASYNC_PRELOAD)
+   pthread_spin_lock(&em->lock);
+#endif
    em->ref--;
 /*   printf("M: %s ref-- = %i\n", em->name, em->ref); */
+#if defined(HAVE_PTHREAD_H) && defined(BUILD_ASYNC_PRELOAD)
+   pthread_spin_unlock(&em->lock);
+#endif
 }
 
 static int use_count = 0;

legacy/evas/src/lib/file/evas_module.h

@@ -50,6 +50,10 @@ struct _Evas_Module
    int           ref; /* how many refs */
    int           last_used; /* the cycle count when it was last used */
 
+#if defined(HAVE_PTHREAD_H) && defined(BUILD_ASYNC_PRELOAD)
+   pthread_spinlock_t lock;
+#endif
+
    unsigned char	loaded : 1;
 };