/* 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 (GObject *object); static void gst_thread_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec); static void gst_thread_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec); static GstElementStateReturn gst_thread_change_state (GstElement *element); #ifndef GST_DISABLE_LOADSAVE static xmlNodePtr gst_thread_save_thyself (GstObject *object, xmlNodePtr parent); static void gst_thread_restore_thyself (GstObject *object, xmlNodePtr self); #endif 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 }; GType gst_thread_get_type(void) { static GType thread_type = 0; if (!thread_type) { static const GTypeInfo thread_info = { sizeof(GstThreadClass), NULL, NULL, (GClassInitFunc)gst_thread_class_init, NULL, NULL, sizeof(GstThread), 4, (GInstanceInitFunc)gst_thread_init, }; thread_type = g_type_register_static(GST_TYPE_BIN, "GstThread", &thread_info, 0); } return thread_type; } static void gst_thread_class_init (GstThreadClass *klass) { GObjectClass *gobject_class; GstObjectClass *gstobject_class; GstElementClass *gstelement_class; GstBinClass *gstbin_class; gobject_class = (GObjectClass*)klass; gstobject_class = (GstObjectClass*)klass; gstelement_class = (GstElementClass*)klass; gstbin_class = (GstBinClass*)klass; parent_class = g_type_class_ref (GST_TYPE_BIN); g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_CREATE_THREAD, g_param_spec_boolean("create_thread", "Create Thread", "Whether to create a thread.", TRUE,G_PARAM_READWRITE)); // FIXME! // gobject_class->destroy = gst_thread_real_destroy; #ifndef GST_DISABLE_LOADSAVE gstobject_class->save_thyself = gst_thread_save_thyself; gstobject_class->restore_thyself = gst_thread_restore_thyself; #endif gstelement_class->change_state = gst_thread_change_state; // gstbin_class->schedule = gst_thread_schedule_dummy; gobject_class->set_property = gst_thread_set_property; gobject_class->get_property = gst_thread_get_property; } 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)); thread->ppid = getpid(); // gst_element_set_manager(GST_ELEMENT(thread),GST_ELEMENT(thread)); } static void gst_thread_real_destroy (GObject *object) { GstThread *thread = GST_THREAD (object); GST_DEBUG (GST_CAT_REFCOUNTING,"destroy()\n"); g_mutex_free (thread->lock); g_cond_free (thread->cond); // FIXME! // if (G_OBJECT_CLASS (parent_class)->destroy) // G_OBJECT_CLASS (parent_class)->destroy (object); gst_object_destroy (GST_OBJECT (GST_ELEMENT_SCHED (thread))); gst_object_unref (GST_OBJECT (GST_ELEMENT_SCHED (thread))); } static void gst_thread_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec) { /* it's not null if we got it, but it might not be ours */ g_return_if_fail (GST_IS_THREAD (object)); switch (prop_id) { case ARG_CREATE_THREAD: if (g_value_get_boolean(value)) { 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: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_thread_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec) { /* it's not null if we got it, but it might not be ours */ g_return_if_fail (GST_IS_THREAD (object)); switch (prop_id) { case ARG_CREATE_THREAD: g_value_set_boolean(value, GST_FLAG_IS_SET (object, GST_THREAD_CREATE)); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); 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); } #define THR_INFO(format,args...) \ GST_INFO_ELEMENT(GST_CAT_THREAD, thread, "sync(" GST_DEBUG_THREAD_FORMAT "): " format , \ GST_DEBUG_THREAD_ARGS(thread->pid) , ## args ) #define THR_DEBUG(format,args...) \ GST_DEBUG_ELEMENT(GST_CAT_THREAD, thread, "sync(" GST_DEBUG_THREAD_FORMAT "): " format , \ GST_DEBUG_THREAD_ARGS(thread->pid) , ## args ) #define THR_INFO_MAIN(format,args...) \ GST_INFO_ELEMENT(GST_CAT_THREAD, thread, "sync-main(" GST_DEBUG_THREAD_FORMAT "): " format , \ GST_DEBUG_THREAD_ARGS(thread->ppid) , ## args ) #define THR_DEBUG_MAIN(format,args...) \ GST_DEBUG_ELEMENT(GST_CAT_THREAD, thread, "sync-main(" GST_DEBUG_THREAD_FORMAT "): " format , \ GST_DEBUG_THREAD_ARGS(thread->ppid) , ## args ) static GstElementStateReturn gst_thread_change_state (GstElement *element) { GstThread *thread; gboolean stateset = GST_STATE_SUCCESS; gint transition; pthread_t self = pthread_self(); GstElement *peerelement; 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); THR_INFO("changing state from %s to %s", gst_element_statename(GST_STATE (element)), gst_element_statename(GST_STATE_PENDING (element))); //GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); switch (transition) { case GST_STATE_NULL_TO_READY: // set the state to idle GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); GST_FLAG_UNSET (thread, GST_THREAD_STATE_REAPING); // create the thread if that's what we're supposed to do if (GST_FLAG_IS_SET (thread, GST_THREAD_CREATE)) { THR_DEBUG ("creating thread \"%s\"\n", GST_ELEMENT_NAME (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' THR_DEBUG("waiting for child thread spinup\n"); g_cond_wait(thread->cond,thread->lock); THR_DEBUG("thread claims to be up\n"); g_mutex_unlock(thread->lock); } else { GST_INFO (GST_CAT_THREAD, "NOT creating 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_READY_TO_PAUSED: THR_INFO("readying thread"); // check to see if the thread is somehow changing its own state. // FIXME this is currently illegal, but must somehow be made legal at some point. 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(" GST_DEBUG_THREAD_FORMAT "): setting own thread's state to spinning\n", GST_DEBUG_THREAD_ARGS(thread->pid)); } else { g_mutex_lock(thread->lock); gst_thread_signal_thread(thread,FALSE); } break; case GST_STATE_PAUSED_TO_PLAYING: THR_INFO("starting thread"); // check to see if the thread is somehow changing its own state. // FIXME this is currently illegal, but must somehow be made legal at some point. 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(" GST_DEBUG_THREAD_FORMAT "): setting own thread's state to spinning\n", GST_DEBUG_THREAD_ARGS(thread->pid)); } else { THR_DEBUG("telling thread to start spinning\n"); g_mutex_lock(thread->lock); gst_thread_signal_thread(thread,TRUE); } break; case GST_STATE_PLAYING_TO_PAUSED: THR_INFO("pausing thread"); // check to see if the thread is somehow changing its own state. // FIXME this is currently illegal, but must somehow be made legal at some point. if (pthread_equal(self, thread->thread_id)) { //FIXME this should not happen GST_DEBUG(GST_CAT_THREAD,"no sync(" GST_DEBUG_THREAD_FORMAT "): setting own thread's state to paused\n", GST_DEBUG_THREAD_ARGS(thread->pid)); GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); g_assert(!pthread_equal(self, thread->thread_id)); } 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); GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); while (elements) { GstElement *e = GST_ELEMENT(elements->data); g_assert(e); THR_DEBUG(" 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 THR_DEBUG("waking queue \"%s\"\n",GST_ELEMENT_NAME(e)); GST_LOCK(e); g_cond_signal((GST_QUEUE(e)->emptycond)); g_cond_signal((GST_QUEUE(e)->fullcond)); GST_UNLOCK(e); } else { GList *pads = GST_ELEMENT_PADS(e); while (pads) { GstPad *p = GST_PAD(pads->data); pads = g_list_next(pads); peerelement = GST_PAD_PARENT(GST_PAD_PEER(p)); if (!peerelement) continue; // deal with case where there's no peer if (!GST_FLAG_IS_SET(peerelement,GST_ELEMENT_DECOUPLED)) { GST_DEBUG(GST_CAT_THREAD,"peer element isn't DECOUPLED\n"); continue; } // FIXME this needs to go away eventually if (!GST_IS_QUEUE(peerelement)) { GST_DEBUG(GST_CAT_THREAD,"peer element isn't a Queue\n"); continue; } if (GST_ELEMENT_SCHED(peerelement) != GST_ELEMENT_SCHED(thread)) { THR_DEBUG(" element \"%s\" has pad cross sched boundary\n",GST_ELEMENT_NAME(e)); GST_LOCK(peerelement); g_cond_signal(GST_QUEUE(peerelement)->emptycond); g_cond_signal(GST_QUEUE(peerelement)->fullcond); GST_UNLOCK(peerelement); } } } } THR_DEBUG("waiting for thread to stop spinning\n"); g_cond_wait (thread->cond, thread->lock); THR_DEBUG("telling thread to pause\n"); gst_thread_signal_thread(thread,FALSE); } break; case GST_STATE_READY_TO_NULL: THR_INFO("stopping thread"); GST_FLAG_SET (thread, GST_THREAD_STATE_REAPING); // check to see if the thread is somehow changing its own state. // FIXME this is currently illegal, but must somehow be made legal at some point. if (pthread_equal(self, thread->thread_id)) { //FIXME this should not happen g_assert(!pthread_equal(self, thread->thread_id)); THR_DEBUG("setting own thread's state to NULL (paused)\n"); GST_FLAG_UNSET (thread, GST_THREAD_STATE_SPINNING); } else { THR_DEBUG("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); break; case GST_STATE_PAUSED_TO_READY: THR_INFO("stopping thread"); // check to see if the thread is somehow changing its own state. // FIXME this is currently illegal, but must somehow be made legal at some point. 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(" GST_DEBUG_THREAD_FORMAT "): setting own thread's state to spinning\n", GST_DEBUG_THREAD_ARGS(thread->pid)); } else { THR_DEBUG("telling thread to stop spinning\n"); g_mutex_lock(thread->lock); gst_thread_signal_thread(thread,FALSE); } break; default: break; } return stateset; } static void gst_thread_update_state (GstThread *thread) { // check for state change if (GST_STATE_PENDING(thread) != GST_STATE_VOID_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; thread->pid = getpid(); THR_INFO_MAIN("thread is running"); // first we need to change the state of all the children 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 /* DEPRACATED for INCSCHED1 THR_DEBUG_MAIN("creating plan for thread\n"); if (GST_BIN_CLASS (parent_class)->schedule) GST_BIN_CLASS (parent_class)->schedule (GST_BIN (thread)); */ // THR_DEBUG_MAIN("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 THR_DEBUG_MAIN("thread has indicated spinup to parent process\n"); /***** THREAD IS NOW IN READY STATE *****/ while (!GST_FLAG_IS_SET (thread, GST_THREAD_STATE_REAPING)) { // NOTE we hold the thread lock at this point // what we do depends on what state we're in switch (GST_STATE(thread)) { // NOTE: cannot be in NULL, we're not running in that state at all case GST_STATE_READY: // wait to be set to either the NULL or PAUSED states THR_DEBUG_MAIN("thread in %s state, waiting for either %s or %s\n", gst_element_statename(GST_STATE_READY), gst_element_statename(GST_STATE_NULL), gst_element_statename(GST_STATE_PAUSED)); g_cond_wait(thread->cond,thread->lock); // been signaled, we need to state transition now and signal back gst_thread_update_state(thread); THR_DEBUG_MAIN("done with state transition, signaling back to parent process\n"); g_cond_signal(thread->cond); // g_mutex_unlock(thread->lock); // now we decide what to do next (FIXME can be collapsed to a continue) if (GST_STATE(thread) == GST_STATE_NULL) { // REAPING must be set, we can simply break this iteration continue; } else { // PAUSED is the next state, we can wait for that next continue; } break; case GST_STATE_PAUSED: // wait to be set to either the READY or PLAYING states THR_DEBUG_MAIN("thread in %s state, waiting for either %s or %s\n", gst_element_statename(GST_STATE_PAUSED), gst_element_statename(GST_STATE_READY), gst_element_statename(GST_STATE_PLAYING)); g_cond_wait(thread->cond,thread->lock); // been signaled, we need to state transition now and signal back gst_thread_update_state(thread); g_cond_signal(thread->cond); // g_mutex_unlock(thread->lock); // now we decide what to do next if (GST_STATE(thread) == GST_STATE_READY) { // READY is the next state, we can wait for that next continue; } else { g_mutex_unlock(thread->lock); // PLAYING is coming up, so we can now start spinning 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); // THR_DEBUG_MAIN("removed spinning state due to failed iteration!\n"); // FIXME FIXME FIXME this is ugly! THR_DEBUG_MAIN("iteration failed, something very wrong, spinning to let parent sync\n"); while (GST_FLAG_IS_SET(thread, GST_THREAD_STATE_SPINNING)) ; } } g_mutex_lock(thread->lock); // once we're here, SPINNING has stopped, we should signal that we're done THR_DEBUG_MAIN("SPINNING stopped, signaling back to parent process\n"); g_cond_signal (thread->cond); // now we can wait for PAUSED continue; } break; case GST_STATE_PLAYING: // wait to be set to PAUSED THR_DEBUG_MAIN("thread in %s state, waiting for %s\n", gst_element_statename(GST_STATE_PLAYING), gst_element_statename(GST_STATE_PAUSED)); g_cond_wait(thread->cond,thread->lock); // been signaled, we need to state transition now and signal back gst_thread_update_state(thread); g_cond_signal(thread->cond); // g_mutex_unlock(thread->lock); // now we decide what to do next // there's only PAUSED, we we just wait for it continue; break; } // need to grab the lock so we're ready for the top of the loop // g_mutex_lock(thread->lock); } /* while (!GST_FLAG_IS_SET (thread, GST_THREAD_STATE_REAPING)) { // start out by waiting for a state change into spinning THR_DEBUG_MAIN("waiting for signal from parent process (at top of while())\n"); g_cond_wait (thread->cond,thread->lock); THR_DEBUG_MAIN("woken up with %s pending\n",gst_element_statename(GST_STATE(thread))); // now is a good time to change the state of the children and the thread itself gst_thread_update_state (thread); THR_DEBUG_MAIN("done changing state, signaling back\n"); g_cond_signal (thread->cond); g_mutex_unlock (thread->lock); THR_DEBUG_MAIN("finished sycnronizing with main process\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); THR_DEBUG_MAIN("removed spinning state due to failed iteration!\n"); } } g_mutex_lock (thread->lock); if (GST_STATE_PENDING(thread) == GST_STATE_PAUSED) { // we've stopped spinning, because of PLAYING->PAUSED THR_DEBUG_MAIN("SPINNING flag unset, signaling parent process we're stopped\n"); // we need to signal back that we've stopped spinning g_cond_signal (thread->cond); } // THR_DEBUG_MAIN("signaling that the thread is out of the SPINNING loop\n"); // g_cond_signal (thread->cond); // g_cond_wait (thread->cond, thread->lock); // THR_DEBUG_MAIN("parent process has signaled at bottom of while\n"); // // now change the children's and thread's state // gst_thread_update_state (thread); // THR_DEBUG_MAIN("done changing state, signaling back to parent process\n"); // g_cond_signal (thread->cond); // // don't release the mutex, we hold that into the top of the loop // THR_DEBUG_MAIN("done syncing with parent process 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); THR_DEBUG("thread locked\n"); // g_mutex_lock(thread->lock); // if (!spinning) { // THR_DEBUG("waiting for spindown\n"); // g_cond_wait (thread->cond, thread->lock); // } THR_DEBUG("signaling\n"); g_cond_signal (thread->cond); THR_DEBUG("waiting for ack\n"); g_cond_wait (thread->cond,thread->lock); THR_DEBUG("got ack\n"); THR_DEBUG("unlocking\n"); g_mutex_unlock(thread->lock); THR_DEBUG("unlocked\n"); } #ifndef GST_DISABLE_LOADSAVE 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; } 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); } #endif // GST_DISABLE_LOADSAVE