netsurf/frontends/gtk/schedule.c
2017-09-07 15:30:08 +01:00

137 lines
4.3 KiB
C

/*
* Copyright 2006-2007 Daniel Silverstone <dsilvers@digital-scurf.org>
*
* This file is part of NetSurf, http://www.netsurf-browser.org/
*
* NetSurf is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* NetSurf is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <glib.h>
#include <stdlib.h>
#include <stdbool.h>
#include "utils/errors.h"
#include "utils/log.h"
#include "gtk/schedule.h"
/** Killable callback closure embodiment. */
typedef struct {
void (*callback)(void *); /**< The callback function. */
void *context; /**< The context for the callback. */
bool callback_killed; /**< Whether or not this was killed. */
} _nsgtk_callback_t;
/** List of callbacks which have occurred and are pending running. */
static GList *pending_callbacks = NULL;
/** List of callbacks which are queued to occur in the future. */
static GList *queued_callbacks = NULL;
/** List of callbacks which are about to be run in this ::schedule_run. */
static GList *this_run = NULL;
static gboolean
nsgtk_schedule_generic_callback(gpointer data)
{
_nsgtk_callback_t *cb = (_nsgtk_callback_t *)(data);
if (cb->callback_killed) {
/* This callback instance has been killed. */
NSLOG(schedule, DEBUG, "CB at %p already dead.", cb);
}
queued_callbacks = g_list_remove(queued_callbacks, cb);
pending_callbacks = g_list_append(pending_callbacks, cb);
return FALSE;
}
static void
nsgtk_schedule_kill_callback(void *_target, void *_match)
{
_nsgtk_callback_t *target = (_nsgtk_callback_t *)_target;
_nsgtk_callback_t *match = (_nsgtk_callback_t *)_match;
if ((target->callback == match->callback) &&
(target->context == match->context)) {
NSLOG(schedule, DEBUG,
"Found match for %p(%p), killing.",
target->callback, target->context);
target->callback = NULL;
target->context = NULL;
target->callback_killed = true;
}
}
static void
schedule_remove(void (*callback)(void *p), void *p)
{
_nsgtk_callback_t cb_match = {
.callback = callback,
.context = p,
};
g_list_foreach(queued_callbacks,
nsgtk_schedule_kill_callback, &cb_match);
g_list_foreach(pending_callbacks,
nsgtk_schedule_kill_callback, &cb_match);
g_list_foreach(this_run,
nsgtk_schedule_kill_callback, &cb_match);
}
/* exported interface documented in gtk/schedule.h */
nserror nsgtk_schedule(int t, void (*callback)(void *p), void *p)
{
_nsgtk_callback_t *cb;
/* Kill any pending schedule of this kind. */
schedule_remove(callback, p);
if (t < 0) {
return NSERROR_OK;
}
cb = malloc(sizeof(_nsgtk_callback_t));
cb->callback = callback;
cb->context = p;
cb->callback_killed = false;
/* Prepend is faster right now. */
queued_callbacks = g_list_prepend(queued_callbacks, cb);
g_timeout_add(t, nsgtk_schedule_generic_callback, cb);
return NSERROR_OK;
}
bool
schedule_run(void)
{
/* Capture this run of pending callbacks into the list. */
this_run = pending_callbacks;
if (this_run == NULL)
return false; /* Nothing to do */
/* Clear the pending list. */
pending_callbacks = NULL;
NSLOG(schedule, DEBUG,
"Captured a run of %d callbacks to fire.",
g_list_length(this_run));
/* Run all the callbacks which made it this far. */
while (this_run != NULL) {
_nsgtk_callback_t *cb = (_nsgtk_callback_t *)(this_run->data);
this_run = g_list_remove(this_run, this_run->data);
if (!cb->callback_killed)
cb->callback(cb->context);
free(cb);
}
return true;
}