evas: add infrastructure for Evas_Loader to know if what they are working on is still useful.

src/lib/evas/Evas_Loader.h

@@ -134,6 +134,7 @@ typedef Efl_Image_Load_Error Evas_Load_Error;
 #define EVAS_LOAD_ERROR_RESOURCE_ALLOCATION_FAILED EFL_IMAGE_LOAD_ERROR_RESOURCE_ALLOCATION_FAILED
 #define EVAS_LOAD_ERROR_CORRUPT_FILE EFL_IMAGE_LOAD_ERROR_CORRUPT_FILE
 #define EVAS_LOAD_ERROR_UNKNOWN_FORMAT EFL_IMAGE_LOAD_ERROR_UNKNOWN_FORMAT
+#define EVAS_LOAD_ERROR_CANCELLED EFL_IMAGE_LOAD_ERROR_CANCELLED
 
 typedef Emile_Image_Animated_Loop_Hint Evas_Image_Animated_Loop_Hint;
 
@@ -199,6 +200,22 @@ struct _Evas_Image_Load_Func
 EAPI Eina_Bool    evas_module_register   (const Evas_Module_Api *module, Evas_Module_Type type);
 EAPI Eina_Bool    evas_module_unregister (const Evas_Module_Api *module, Evas_Module_Type type);
 
+EAPI Eina_Bool    evas_module_task_cancelled (void);
+
+#define EVAS_MODULE_TASK_CHECK(Count, Mask, Error, Error_Handler)       \
+  do {                                                                  \
+     Count++;                                                           \
+     if ((Count & Mask) == Mask)                                        \
+       {                                                                \
+          Count = 0;                                                    \
+          if (evas_module_task_cancelled())                             \
+            {                                                           \
+               *Error = EFL_IMAGE_LOAD_ERROR_CANCELLED;                 \
+               goto Error_Handler;                                      \
+            }                                                           \
+       }                                                                \
+  } while (0)
+
 #define EVAS_MODULE_DEFINE(Type, Tn, Name)		\
   Eina_Bool evas_##Tn##_##Name##_init(void)		\
   {							\

src/lib/evas/file/evas_module.c

@@ -28,6 +28,51 @@
 #define EVAS_MODULE_NO_VG_SAVERS 0
 #endif
 
+typedef struct _Evas_Module_Task Evas_Module_Task;
+struct _Evas_Module_Task
+{
+   Eina_Bool (*cancelled)(void *data);
+   void *data;
+};
+
+static Eina_TLS task = 0;
+
+EAPI Eina_Bool
+evas_module_task_cancelled(void)
+{
+   Evas_Module_Task *t;
+
+   t = eina_tls_get(task);
+   if (!t) return EINA_FALSE;
+
+   return t->cancelled(t->data);
+}
+
+EAPI void
+evas_module_task_register(Eina_Bool (*cancelled)(void *data), void *data)
+{
+   Evas_Module_Task *t;
+
+   t = malloc(sizeof (Evas_Module_Task));
+   if (!t) return ;
+
+   t->cancelled = cancelled;
+   t->data = data;
+
+   eina_tls_set(task, t);
+}
+
+EAPI void
+evas_module_task_unregister(void)
+{
+    Evas_Module_Task *t;
+
+    t = eina_tls_get(task);
+    if (!t) return ;
+
+    eina_tls_set(task, NULL);
+    free(t);
+}
 
 static Eina_Hash *evas_modules[6] = {
   NULL,
@@ -318,6 +363,8 @@ evas_module_init(void)
 
    evas_engines = eina_array_new(4);
 
+   eina_tls_cb_new(&task, (Eina_TLS_Delete_Cb) evas_module_task_unregister);
+
    for (i = 0; evas_static_module[i].init; ++i)
      evas_static_module[i].init();
 }
@@ -694,6 +741,8 @@ evas_module_shutdown(void)
    eina_hash_free(evas_modules[EVAS_MODULE_TYPE_VG_SAVER]);
    evas_modules[EVAS_MODULE_TYPE_VG_SAVER] = NULL;
 
+   eina_tls_free(task);
+
    EINA_LIST_FREE(evas_module_paths, path)
      free(path);
 

src/lib/evas/include/evas_private.h

@@ -1956,6 +1956,9 @@ Eina_Bool evas_preload_thread_cancelled_is(Evas_Preload_Pthread *thread);
 void _evas_walk(Evas_Public_Data *e_pd);
 void _evas_unwalk(Evas_Public_Data *e_pd);
 
+EAPI void evas_module_task_register(Eina_Bool (*cancelled)(void *data), void *data);
+EAPI void evas_module_task_unregister(void);
+
 // expose for use in engines
 EAPI int _evas_module_engine_inherit(Evas_Func *funcs, char *name);
 EAPI const char *_evas_module_libdir_get(void);