/* GStreamer * Copyright (C) 1999,2000 Erik Walthinsen * 2000 Wim Taymans * * gstthread.c: Threaded container object * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #include //#define GST_DEBUG_ENABLED #include "gst_private.h" #include "gstthread.h" #include "gstscheduler.h" #include "gstqueue.h" GstElementDetails gst_thread_details = { "Threaded container", "Bin", "Container that creates/manages a thread", VERSION, "Erik Walthinsen ", "(C) 1999, 2000", }; /* Thread signals and args */ enum { /* FILL ME */ LAST_SIGNAL }; enum { SPINUP=0, STATECHANGE, STARTUP }; enum { ARG_0, ARG_CREATE_THREAD, }; static void gst_thread_class_init (GstThreadClass *klass); static void gst_thread_init (GstThread *thread); static void gst_thread_real_destroy (GtkObject *gtk_object); static void gst_thread_set_arg (GtkObject *object, GtkArg *arg, guint id); static void gst_thread_get_arg (GtkObject *object, GtkArg *arg, guint id); static GstElementStateReturn gst_thread_change_state (GstElement *element); static xmlNodePtr gst_thread_save_thyself (GstObject *object, xmlNodePtr parent); static void gst_thread_restore_thyself (GstObject *object, xmlNodePtr self); static void gst_thread_signal_thread (GstThread *thread, gboolean spinning); static void* gst_thread_main_loop (void *arg); static GstBinClass *parent_class = NULL; //static guint gst_thread_signals[LAST_SIGNAL] = { 0 }; GtkType gst_thread_get_type(void) { static GtkType thread_type = 0; if (!thread_type) { static const GtkTypeInfo thread_info = { "GstThread", sizeof(GstThread), sizeof(GstThreadClass), (GtkClassInitFunc)gst_thread_class_init, (GtkObjectInitFunc)gst_thread_init, (GtkArgSetFunc)NULL, (GtkArgGetFunc)NULL, (GtkClassInitFunc)NULL, }; thread_type = gtk_type_unique(GST_TYPE_BIN,&thread_info); } return thread_type; } static void gst_thread_class_init (GstThreadClass *klass) { GtkObjectClass *gtkobject_class; GstObjectClass *gstobject_class; GstElementClass *gstelement_class; GstBinClass *gstbin_class; gtkobject_class = (GtkObjectClass*)klass; gstobject_class = (GstObjectClass*)klass; gstelement_class = (GstElementClass*)klass; gstbin_class = (GstBinClass*)klass; parent_class = gtk_type_class (GST_TYPE_BIN); gtk_object_add_arg_type ("GstThread::create_thread", GTK_TYPE_BOOL, GTK_ARG_READWRITE, ARG_CREATE_THREAD); gtkobject_class->destroy = gst_thread_real_destroy; gstobject_class->save_thyself = gst_thread_save_thyself; gstobject_class->restore_thyself = gst_thread_restore_thyself; gstelement_class->change_state = gst_thread_change_state; // gstbin_class->schedule = gst_thread_schedule_dummy; gtkobject_class->set_arg = gst_thread_set_arg; gtkobject_class->get_arg = gst_thread_get_arg; } static void gst_thread_init (GstThread *thread) { GST_DEBUG (GST_CAT_THREAD,"initializing thread\n"); // we're a manager by default GST_FLAG_SET (thread, GST_BIN_FLAG_MANAGER); // default is to create a thread GST_FLAG_SET (thread, GST_THREAD_CREATE); thread->lock = g_mutex_new(); thread->cond = g_cond_new(); GST_ELEMENT_SCHED(thread) = gst_schedule_new(GST_ELEMENT(thread)); GST_DEBUG(GST_CAT_THREAD, "thread's scheduler is %p\n",GST_ELEMENT_SCHED(thread)); // gst_element_set_manager(GST_ELEMENT(thread),GST_ELEMENT(thread)); } static void gst_thread_real_destroy (GtkObject *gtk_object) { GstThread *thread = GST_THREAD (gtk_object); GST_DEBUG (GST_CAT_REFCOUNTING,"destroy()\n"); g_mutex_free (thread->lock); g_cond_free (thread->cond); if (GTK_OBJECT_CLASS (parent_class)->destroy) GTK_OBJECT_CLASS (parent_class)->destroy (gtk_object); gst_object_destroy (GST_OBJECT (GST_ELEMENT_SCHED (thread))); gst_object_unref (GST_OBJECT (GST_ELEMENT_SCHED (thread))); } static void gst_thread_set_arg (GtkObject *object, GtkArg *arg, guint id) { /* it's not null if we got it, but it might not be ours */ g_return_if_fail (GST_IS_THREAD (object)); switch(id) { case ARG_CREATE_THREAD: if (GTK_VALUE_BOOL (*arg)) { GST_INFO (GST_CAT_THREAD,"turning ON the creation of the thread"); GST_FLAG_SET (object, GST_THREAD_CREATE); // GST_DEBUG (GST_CAT_THREAD,"flags are 0x%08x\n", GST_FLAGS (object)); } else { GST_INFO (GST_CAT_THREAD,"gstthread: turning OFF the creation of the thread"); GST_FLAG_UNSET (object, GST_THREAD_CREATE); // GST_DEBUG (GST_CAT_THREAD,"gstthread: flags are 0x%08x\n", GST_FLAGS (object)); } break; default: break; } } static void gst_thread_get_arg (GtkObject *object, GtkArg *arg, guint id) { /* it's not null if we got it, but it might not be ours */ g_return_if_fail (GST_IS_THREAD (object)); switch (id) { case ARG_CREATE_THREAD: GTK_VALUE_BOOL (*arg) = GST_FLAG_IS_SET (object, GST_THREAD_CREATE); break; default: break; } } /** * gst_thread_new: * @name: the name of the thread * * Create a new thread with the given name. * * Returns: The new thread */ GstElement* gst_thread_new (const guchar *name) { return gst_elementfactory_make ("thread", name); } static GstElementStateReturn gst_thread_change_state (GstElement *element) { GstThread *thread; gboolean stateset = GST_STATE_SUCCESS; gint transition; pthread_t self = pthread_self(); g_return_val_if_fail (GST_IS_THREAD(element), FALSE); GST_DEBUG_ENTER("(\"%s\")",GST_ELEMENT_NAME(element)); thread = GST_THREAD (element); GST_DEBUG (GST_CAT_THREAD, "**** THREAD %ld changing THREAD %ld ****\n",self,thread->thread_id); GST_DEBUG (GST_CAT_THREAD, "**** current pid=%d\n",getpid()); transition = GST_STATE_TRANSITION (element); GST_INFO (GST_CAT_THREAD,"thread \"%s\" changing state to %s from %s", GST_ELEMENT_NAME (GST_ELEMENT (element)), _gst_print_statename(GST_STATE_PENDING (element)), _gst_print_statename(GST_STATE (element))); //GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); switch (transition) { case GST_STATE_NULL_TO_READY: // we want to prepare our internal state for doing the iterations GST_INFO (GST_CAT_THREAD, "preparing thread \"%s\" for iterations:", GST_ELEMENT_NAME (GST_ELEMENT (element))); // set the state to idle GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); // create the thread if that's what we're supposed to do // GST_INFO (GST_CAT_THREAD, "flags are 0x%08x", GST_FLAGS (thread)); if (GST_FLAG_IS_SET (thread, GST_THREAD_CREATE)) { GST_DEBUG (GST_CAT_THREAD, "creating thread \"%s\"\n", GST_ELEMENT_NAME (GST_ELEMENT (element))); g_mutex_lock(thread->lock); // create the thread pthread_create (&thread->thread_id, NULL, gst_thread_main_loop, thread); // wait for it to 'spin up' GST_DEBUG (GST_CAT_THREAD, "sync: waiting for spinup\n"); g_cond_wait(thread->cond,thread->lock); GST_DEBUG (GST_CAT_THREAD, "sync: thread claims to be up\n"); g_mutex_unlock(thread->lock); } else { GST_INFO (GST_CAT_THREAD, "NOT starting thread \"%s\"", GST_ELEMENT_NAME (GST_ELEMENT (element))); // punt and change state on all the children if (GST_ELEMENT_CLASS (parent_class)->change_state) stateset = GST_ELEMENT_CLASS (parent_class)->change_state (element); } break; case GST_STATE_PAUSED_TO_PLAYING: case GST_STATE_READY_TO_PLAYING: // if (!stateset) return FALSE; GST_INFO (GST_CAT_THREAD, "starting thread \"%s\"", GST_ELEMENT_NAME (GST_ELEMENT (element))); if (pthread_equal(self, thread->thread_id)) { //FIXME this should not happen g_assert(!pthread_equal(self, thread->thread_id)); GST_FLAG_SET(thread, GST_THREAD_STATE_SPINNING); GST_DEBUG(GST_CAT_THREAD,"no sync: setting own thread's state to spinning\n"); } else { GST_DEBUG(GST_CAT_THREAD,"sync: telling thread to start spinning\n"); g_mutex_lock(thread->lock); gst_thread_signal_thread(thread,TRUE); } break; case GST_STATE_PLAYING_TO_PAUSED: GST_INFO (GST_CAT_THREAD,"pausing thread \"%s\"", GST_ELEMENT_NAME (GST_ELEMENT (element))); if (pthread_equal(self, thread->thread_id)) { //FIXME this should not happen g_assert(!pthread_equal(self, thread->thread_id)); GST_DEBUG(GST_CAT_THREAD,"no sync: setting own thread's state to paused\n"); GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); } else { GList *elements = (element->sched)->elements; // the following code ensures that the bottom half of thread will run // to perform each elements' change_state() (by calling gstbin.c:: // change_state()). // + the pending state was already set by gstelement.c::set_state() // + find every queue we manage, and signal its empty and full conditions g_mutex_lock(thread->lock); while (elements) { GstElement *e = GST_ELEMENT(elements->data); g_assert(e); GST_DEBUG(GST_CAT_THREAD," element %s\n",GST_ELEMENT_NAME(e)); elements = g_list_next(elements); if (GST_IS_QUEUE(e)) { //FIXME make this more efficient by only waking queues that are asleep //FIXME and only waking the appropriate condition (depending on if it's //FIXME on up- or down-stream side) // //FIXME also make this more efficient by keeping list of managed queues GST_DEBUG(GST_CAT_THREAD,"sync: waking queue \"%s\"\n", GST_ELEMENT_NAME(e)); g_cond_signal((GST_QUEUE(e)->emptycond)); g_cond_signal((GST_QUEUE(e)->fullcond)); } else { GList *pads = GST_ELEMENT_PADS(e); while (pads) { GstPad *p = GST_PAD(pads->data); pads = g_list_next(pads); if (GST_IS_REAL_PAD(p) && GST_ELEMENT_SCHED(e) != GST_ELEMENT_SCHED(GST_ELEMENT(GST_PAD_PARENT(GST_PAD_PEER(p))))) { GST_DEBUG(GST_CAT_THREAD," element \"%s\" has pad cross sched boundary\n",GST_ELEMENT_NAME(e)); // FIXME i assume this signals our own (current) thread so don't need to lock // FIXME however, this *may* go to yet another thread for which we need locks // FIXME i'm too tired to deal with this now g_cond_signal(GST_QUEUE(GST_ELEMENT(GST_PAD_PARENT(GST_PAD_PEER(p))))->emptycond); g_cond_signal(GST_QUEUE(GST_ELEMENT(GST_PAD_PARENT(GST_PAD_PEER(p))))->fullcond); } } } } GST_DEBUG(GST_CAT_THREAD,"sync: telling thread to pause\n"); gst_thread_signal_thread(thread,FALSE); } break; case GST_STATE_PLAYING_TO_READY: if (pthread_equal(self, thread->thread_id)) { //FIXME this should not happen g_assert(!pthread_equal(self, thread->thread_id)); GST_DEBUG(GST_CAT_THREAD,"no sync: setting own thread's state to ready (paused)\n"); GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); } else { GST_DEBUG(GST_CAT_THREAD,"sync: telling thread to pause (ready)\n"); g_mutex_lock(thread->lock); gst_thread_signal_thread(thread,FALSE); } break; case GST_STATE_READY_TO_NULL: GST_INFO (GST_CAT_THREAD,"stopping thread \"%s\"", GST_ELEMENT_NAME (GST_ELEMENT (element))); GST_FLAG_SET (thread, GST_THREAD_STATE_REAPING); if (pthread_equal(self, thread->thread_id)) { //FIXME this should not happen g_assert(!pthread_equal(self, thread->thread_id)); GST_DEBUG(GST_CAT_THREAD,"no sync: setting own thread's state to NULL (paused)\n"); GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); } else { GST_DEBUG(GST_CAT_THREAD,"sync: telling thread to pause (null) - and joining\n"); //MattH FIXME revisit // g_mutex_lock(thread->lock); // gst_thread_signal_thread(thread,FALSE); pthread_join(thread->thread_id,NULL); } GST_FLAG_UNSET(thread,GST_THREAD_STATE_REAPING); GST_FLAG_UNSET(thread,GST_THREAD_STATE_STARTED); GST_FLAG_UNSET(thread,GST_THREAD_STATE_SPINNING); GST_FLAG_UNSET(thread,GST_THREAD_STATE_ELEMENT_CHANGED); if (GST_ELEMENT_CLASS (parent_class)->change_state) stateset = GST_ELEMENT_CLASS (parent_class)->change_state (GST_ELEMENT(thread)); break; default: break; } return stateset; } static void gst_thread_update_state (GstThread *thread) { // check for state change if (GST_STATE_PENDING(thread) != GST_STATE_NONE_PENDING) { // punt and change state on all the children if (GST_ELEMENT_CLASS (parent_class)->change_state) GST_ELEMENT_CLASS (parent_class)->change_state (GST_ELEMENT(thread)); } } /** * gst_thread_main_loop: * @arg: the thread to start * * The main loop of the thread. The thread will iterate * while the state is GST_THREAD_STATE_SPINNING */ static void * gst_thread_main_loop (void *arg) { GstThread *thread = GST_THREAD (arg); gint stateset; GST_INFO (GST_CAT_THREAD,"thread \"%s\" is running with PID %d", GST_ELEMENT_NAME (GST_ELEMENT (thread)), getpid ()); // first we need to change the state of all the children GST_DEBUG (GST_CAT_THREAD,"thread started, setting children's state\n"); if (GST_ELEMENT_CLASS (parent_class)->change_state) stateset = GST_ELEMENT_CLASS (parent_class)->change_state (GST_ELEMENT(thread)); // construct the plan and signal back GST_DEBUG (GST_CAT_THREAD,"creating plan for thread\n"); if (GST_BIN_CLASS (parent_class)->schedule) GST_BIN_CLASS (parent_class)->schedule (GST_BIN (thread)); GST_DEBUG (GST_CAT_THREAD, "sync: indicating spinup\n"); g_mutex_lock (thread->lock); g_cond_signal (thread->cond); // don't unlock the mutex because we hold it into the top of the while loop GST_DEBUG (GST_CAT_THREAD, "sync: thread has indicated spinup to main process\n"); while (!GST_FLAG_IS_SET (thread, GST_THREAD_STATE_REAPING)) { // start out by waiting for a state change into spinning GST_DEBUG (GST_CAT_THREAD, "sync: waiting at top of while for signal from main process\n"); g_cond_wait (thread->cond,thread->lock); GST_DEBUG (GST_CAT_THREAD, "sync: main process has signaled at top of while\n"); // now is a good time to change the state of the children and the thread itself gst_thread_update_state (thread); GST_DEBUG (GST_CAT_THREAD, "sync: done changing state, signaling back\n"); g_cond_signal (thread->cond); g_mutex_unlock (thread->lock); GST_DEBUG (GST_CAT_THREAD, "sync: done syncing with main thread at top of while\n"); while (GST_FLAG_IS_SET (thread, GST_THREAD_STATE_SPINNING)) { if (!gst_bin_iterate (GST_BIN (thread))) { GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); GST_DEBUG(GST_CAT_THREAD,"sync: removed spinning state due to failed iteration\n"); } } GST_DEBUG (GST_CAT_THREAD, "sync: waiting at bottom of while for signal from main process\n"); g_mutex_lock (thread->lock); GST_DEBUG (GST_CAT_THREAD, "sync: signaling that the thread is out of the SPINNING loop\n"); g_cond_signal (thread->cond); g_cond_wait (thread->cond, thread->lock); GST_DEBUG (GST_CAT_THREAD, "sync: main process has signaled at bottom of while\n"); // now change the children's and thread's state gst_thread_update_state (thread); GST_DEBUG (GST_CAT_THREAD, "sync: done changing state, signaling back\n"); g_cond_signal (thread->cond); // don't release the mutex, we hold that into the top of the loop GST_DEBUG (GST_CAT_THREAD, "sync: done syncning with main thread at bottom of while\n"); } // since we don't unlock at the end of the while loop, do it here g_mutex_unlock (thread->lock); GST_INFO (GST_CAT_THREAD, "gstthread: thread \"%s\" is stopped", GST_ELEMENT_NAME (thread)); return NULL; } // the set flag is to say whether it should set TRUE or FALSE // // WARNING: this has synchronization built in! if you remove or add any // locks, waits, signals, or unlocks you need to be sure they match the // code above (in gst_thread_main_loop()). basically, don't change anything. static void gst_thread_signal_thread (GstThread *thread, gboolean spinning) { // set the spinning state if (spinning) GST_FLAG_SET(thread,GST_THREAD_STATE_SPINNING); else GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); GST_DEBUG (GST_CAT_THREAD, "sync-main: thread locked\n"); // g_mutex_lock(thread->lock); if (!spinning) { GST_DEBUG (GST_CAT_THREAD, "sync-main: waiting for spindown\n"); g_cond_wait (thread->cond, thread->lock); } GST_DEBUG (GST_CAT_THREAD, "sync-main: signaling\n"); g_cond_signal (thread->cond); GST_DEBUG (GST_CAT_THREAD, "sync-main: waiting for ack\n"); g_cond_wait (thread->cond,thread->lock); GST_DEBUG (GST_CAT_THREAD, "sync-main: unlocking\n"); g_mutex_unlock(thread->lock); GST_DEBUG (GST_CAT_THREAD, "sync-main: unlocked\n"); } static void gst_thread_restore_thyself (GstObject *object, xmlNodePtr self) { GST_DEBUG (GST_CAT_THREAD,"gstthread: restore\n"); if (GST_OBJECT_CLASS (parent_class)->restore_thyself) GST_OBJECT_CLASS (parent_class)->restore_thyself (object, self); } static xmlNodePtr gst_thread_save_thyself (GstObject *object, xmlNodePtr self) { if (GST_OBJECT_CLASS (parent_class)->save_thyself) GST_OBJECT_CLASS (parent_class)->save_thyself (object, self); return NULL; }