efl/legacy/ecore/src/lib/ecore/ecore_idler.c

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <stdlib.h>

#include "Ecore.h"
#include "ecore_private.h"


struct _Ecore_Idler
{
   EINA_INLIST;
   ECORE_MAGIC;
   Ecore_Task_Cb func;
   void        *data;
   int          references;
   Eina_Bool    delete_me : 1;
};


static Ecore_Idler *idlers = NULL;
static Ecore_Idler *idler_current = NULL;
static int          idlers_delete_me = 0;

/**
 * Add an idler handler.
 * @param  func The function to call when idling.
 * @param  data The data to be passed to this @p func call.
 * @return A idler handle if successfully added.  NULL otherwise.
 * @ingroup Idle_Group
 *
 * Add an idler handle to the event loop, returning a handle on success and
 * NULL otherwise.  The function @p func will be called repeatedly while
 * no other events are ready to be processed, as long as it returns 1
 * (or ECORE_CALLBACK_RENEW). A return of 0 (or ECORE_CALLBACK_CANCEL) deletes
 * the idler.
 *
 * Idlers are useful for progressively prossessing data without blocking.
 */
EAPI Ecore_Idler *
ecore_idler_add(Ecore_Task_Cb func, const void *data)
{
   Ecore_Idler *ie;

   if (!func) return NULL;
   ie = calloc(1, sizeof(Ecore_Idler));
   if (!ie) return NULL;
   ECORE_MAGIC_SET(ie, ECORE_MAGIC_IDLER);
   ie->func = func;
   ie->data = (void *)data;
   idlers = (Ecore_Idler *) eina_inlist_append(EINA_INLIST_GET(idlers), EINA_INLIST_GET(ie));
   return ie;
}

/**
 * Delete an idler callback from the list to be executed.
 * @param  idler The handle of the idler callback to delete
 * @return The data pointer passed to the idler callback on success.  NULL
 *         otherwise.
 * @ingroup Idle_Group
 */
EAPI void *
ecore_idler_del(Ecore_Idler *idler)
{
   if (!ECORE_MAGIC_CHECK(idler, ECORE_MAGIC_IDLER))
     {
	ECORE_MAGIC_FAIL(idler, ECORE_MAGIC_IDLER,
			 "ecore_idler_del");
	return NULL;
     }
   EINA_SAFETY_ON_TRUE_RETURN_VAL(idler->delete_me, NULL);
   idler->delete_me = 1;
   idlers_delete_me = 1;
   return idler->data;
}

void
_ecore_idler_shutdown(void)
{
   Ecore_Idler *ie;
   while ((ie = idlers))
     {
	idlers = (Ecore_Idler *) eina_inlist_remove(EINA_INLIST_GET(idlers), EINA_INLIST_GET(idlers));
	ECORE_MAGIC_SET(ie, ECORE_MAGIC_NONE);
	free(ie);
     }
   idlers_delete_me = 0;
   idler_current = NULL;
}

int
_ecore_idler_call(void)
{
   if (!idler_current)
     {
	/* regular main loop, start from head */
	idler_current = idlers;
     }
   else
     {
	/* recursive main loop, continue from where we were */
	idler_current = (Ecore_Idler *)EINA_INLIST_GET(idler_current)->next;
     }

   while (idler_current)
     {
	Ecore_Idler *ie = (Ecore_Idler *)idler_current;
	if (!ie->delete_me)
	  {
	     ie->references++;
	     if (!ie->func(ie->data))
	       {
		  if (!ie->delete_me) ecore_idler_del(ie);
	       }
	     ie->references--;
	  }
	if (idler_current) /* may have changed in recursive main loops */
	  idler_current = (Ecore_Idler *)EINA_INLIST_GET(idler_current)->next;
     }
   if (idlers_delete_me)
     {
	Ecore_Idler *l;
	int deleted_idlers_in_use = 0;
	for (l = idlers; l;)
	  {
	     Ecore_Idler *ie = l;
	     l = (Ecore_Idler *) EINA_INLIST_GET(l)->next;
	     if (ie->delete_me)
	       {
		  if (ie->references)
		    {
		       deleted_idlers_in_use++;
		       continue;
		    }

		  idlers = (Ecore_Idler *) eina_inlist_remove(EINA_INLIST_GET(idlers), EINA_INLIST_GET(ie));
		  ECORE_MAGIC_SET(ie, ECORE_MAGIC_NONE);
		  free(ie);
	       }
	  }
	if (!deleted_idlers_in_use)
	  idlers_delete_me = 0;
     }
   if (idlers) return 1;
   return 0;
}

int
_ecore_idler_exist(void)
{
   if (idlers) return 1;
   return 0;
}