/* GStreamer * Copyright (C) 2005 Wim Taymans * * gstcollectpads.c: * * 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. */ /** * SECTION:gstcollectpads * @short_description: manages a set of pads that operate in collect mode * @see_also: * * Manages a set of pads that operate in collect mode. This means that control * is given to the manager of this object when all pads have data. * * * Collectpads are created with gst_collect_pads_new(). A callback should then * be installed with gst_collect_pads_set_function (). * * * Pads are added to the collection with gst_collect_pads_add_pad()/ * gst_collect_pads_remove_pad(). The pad * has to be a sinkpad. The chain and event functions of the pad are * overridden. The element_private of the pad is used to store * private information for the collectpads. * * * For each pad, data is queued in the _chain function or by * performing a pull_range. * * * When data is queued on all pads, the callback function is called. * * * Data can be dequeued from the pad with the gst_collect_pads_pop() method. * One can peek at the data with the gst_collect_pads_peek() function. * These functions will return NULL if the pad received an EOS event. When all * pads return NULL from a gst_collect_pads_peek(), the element can emit an EOS * event itself. * * * Data can also be dequeued in byte units using the gst_collect_pads_available(), * gst_collect_pads_read() and gst_collect_pads_flush() calls. * * * Elements should call gst_collect_pads_start() and gst_collect_pads_stop() in * their state change functions to start and stop the processing of the collecpads. * The gst_collect_pads_stop() call should be called before calling the parent * element state change function in the PAUSED_TO_READY state change to ensure * no pad is blocked and the element can finish streaming. * * * gst_collect_pads_collect() and gst_collect_pads_collect_range() can be used by * elements that start a #GstTask to drive the collect_pads. This feature is however * not yet implemented. * * * * Last reviewed on 2006-05-10 (0.10.6) */ #include "gstcollectpads.h" #include "gst/glib-compat-private.h" GST_DEBUG_CATEGORY_STATIC (collect_pads_debug); #define GST_CAT_DEFAULT collect_pads_debug #define GST_COLLECT_PADS_GET_PRIVATE(obj) \ (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_COLLECT_PADS, GstCollectPadsPrivate)) struct _GstCollectPadsPrivate { GstCollectPadsClipFunction clipfunc; gpointer clipfunc_user_data; }; #define gst_collect_pads_parent_class parent_class G_DEFINE_TYPE (GstCollectPads, gst_collect_pads, GST_TYPE_OBJECT); static void gst_collect_pads_clear (GstCollectPads * pads, GstCollectData * data); static GstFlowReturn gst_collect_pads_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer); static gboolean gst_collect_pads_event (GstPad * pad, GstObject * parent, GstEvent * event); static void gst_collect_pads_finalize (GObject * object); static void ref_data (GstCollectData * data); static void unref_data (GstCollectData * data); static void gst_collect_pads_check_pads_unlocked (GstCollectPads * pads); static void gst_collect_pads_class_init (GstCollectPadsClass * klass) { GObjectClass *gobject_class = (GObjectClass *) klass; g_type_class_add_private (klass, sizeof (GstCollectPadsPrivate)); GST_DEBUG_CATEGORY_INIT (collect_pads_debug, "collectpads", 0, "GstCollectPads"); gobject_class->finalize = gst_collect_pads_finalize; } static void gst_collect_pads_init (GstCollectPads * pads) { pads->priv = GST_COLLECT_PADS_GET_PRIVATE (pads); g_cond_init (&pads->cond); pads->data = NULL; pads->cookie = 0; pads->numpads = 0; pads->queuedpads = 0; pads->eospads = 0; pads->started = FALSE; /* members to manage the pad list */ g_mutex_init (&pads->pad_lock); pads->pad_cookie = 0; pads->pad_list = NULL; } static void gst_collect_pads_finalize (GObject * object) { GSList *collected; GstCollectPads *pads = GST_COLLECT_PADS (object); GST_DEBUG ("finalize"); g_cond_clear (&pads->cond); g_mutex_clear (&pads->pad_lock); /* Remove pads */ collected = pads->pad_list; for (; collected; collected = g_slist_next (collected)) { GstCollectData *pdata = (GstCollectData *) collected->data; unref_data (pdata); } /* Free pads list */ g_slist_foreach (pads->data, (GFunc) unref_data, NULL); g_slist_free (pads->data); g_slist_free (pads->pad_list); G_OBJECT_CLASS (parent_class)->finalize (object); } /** * gst_collect_pads_new: * * Create a new instance of #GstCollectPads. * * MT safe. * * Returns: (transfer full): a new #GstCollectPads, or NULL in case of an error. */ GstCollectPads * gst_collect_pads_new (void) { GstCollectPads *newcoll; newcoll = g_object_newv (GST_TYPE_COLLECT_PADS, 0, NULL); return newcoll; } /** * gst_collect_pads_set_function: * @pads: the collectspads to use * @func: the function to set * @user_data: (closure): user data passed to the function * * Set the callback function and user data that will be called when * all the pads added to the collection have buffers queued. * * MT safe. */ void gst_collect_pads_set_function (GstCollectPads * pads, GstCollectPadsFunction func, gpointer user_data) { g_return_if_fail (pads != NULL); g_return_if_fail (GST_IS_COLLECT_PADS (pads)); GST_OBJECT_LOCK (pads); pads->func = func; pads->user_data = user_data; GST_OBJECT_UNLOCK (pads); } static void ref_data (GstCollectData * data) { g_assert (data != NULL); g_atomic_int_inc (&(data->refcount)); } static void unref_data (GstCollectData * data) { g_assert (data != NULL); g_assert (data->refcount > 0); if (!g_atomic_int_dec_and_test (&(data->refcount))) return; if (data->destroy_notify) data->destroy_notify (data); g_object_unref (data->pad); if (data->buffer) gst_buffer_unref (data->buffer); g_free (data); } /** * gst_collect_pads_add_pad: * @pads: the collectspads to use * @pad: (transfer none): the pad to add * @size: the size of the returned #GstCollectData structure * @destroy_notify: function to be called before the returned #GstCollectData * structure is freed * * Add a pad to the collection of collect pads. The pad has to be * a sinkpad. The refcount of the pad is incremented. Use * gst_collect_pads_remove_pad() to remove the pad from the collection * again. * * You specify a size for the returned #GstCollectData structure * so that you can use it to store additional information. * * You can also specify a #GstCollectDataDestroyNotify that will be called * just before the #GstCollectData structure is freed. It is passed the * pointer to the structure and should free any custom memory and resources * allocated for it. * * The pad will be automatically activated in push mode when @pads is * started. * * MT safe. * * Returns: a new #GstCollectData to identify the new pad. Or NULL * if wrong parameters are supplied. */ GstCollectData * gst_collect_pads_add_pad (GstCollectPads * pads, GstPad * pad, guint size, GstCollectDataDestroyNotify destroy_notify) { GstCollectData *data; g_return_val_if_fail (pads != NULL, NULL); g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), NULL); g_return_val_if_fail (pad != NULL, NULL); g_return_val_if_fail (GST_PAD_IS_SINK (pad), NULL); g_return_val_if_fail (size >= sizeof (GstCollectData), NULL); GST_DEBUG ("adding pad %s:%s", GST_DEBUG_PAD_NAME (pad)); data = g_malloc0 (size); data->collect = pads; data->pad = gst_object_ref (pad); data->buffer = NULL; data->pos = 0; gst_segment_init (&data->segment, GST_FORMAT_UNDEFINED); data->flushing = FALSE; data->new_segment = FALSE; data->eos = FALSE; data->refcount = 1; data->destroy_notify = destroy_notify; GST_COLLECT_PADS_PAD_LOCK (pads); GST_OBJECT_LOCK (pad); gst_pad_set_element_private (pad, data); GST_OBJECT_UNLOCK (pad); pads->pad_list = g_slist_append (pads->pad_list, data); gst_pad_set_chain_function (pad, GST_DEBUG_FUNCPTR (gst_collect_pads_chain)); gst_pad_set_event_function (pad, GST_DEBUG_FUNCPTR (gst_collect_pads_event)); /* activate the pad when needed */ if (pads->started) gst_pad_set_active (pad, TRUE); pads->pad_cookie++; GST_COLLECT_PADS_PAD_UNLOCK (pads); return data; } static gint find_pad (GstCollectData * data, GstPad * pad) { if (data->pad == pad) return 0; return 1; } /** * gst_collect_pads_set_clip_function: * @pads: the collectspads to use * @clipfunc: clip function to install * @user_data: (closure): user data to pass to @clip_func * * Install a clipping function that is called right after a buffer is received * on a pad managed by @pads. See #GstCollectPadsClipFunction for more info. * * Since: 0.10.26 */ void gst_collect_pads_set_clip_function (GstCollectPads * pads, GstCollectPadsClipFunction clipfunc, gpointer user_data) { GstCollectPadsPrivate *priv; g_return_if_fail (pads != NULL); g_return_if_fail (GST_IS_COLLECT_PADS (pads)); priv = pads->priv; priv->clipfunc = clipfunc; priv->clipfunc_user_data = user_data; } /** * gst_collect_pads_remove_pad: * @pads: the collectspads to use * @pad: (transfer none): the pad to remove * * Remove a pad from the collection of collect pads. This function will also * free the #GstCollectData and all the resources that were allocated with * gst_collect_pads_add_pad(). * * The pad will be deactivated automatically when @pads is stopped. * * MT safe. * * Returns: %TRUE if the pad could be removed. */ gboolean gst_collect_pads_remove_pad (GstCollectPads * pads, GstPad * pad) { GstCollectData *data; GSList *list; g_return_val_if_fail (pads != NULL, FALSE); g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), FALSE); g_return_val_if_fail (pad != NULL, FALSE); g_return_val_if_fail (GST_IS_PAD (pad), FALSE); GST_DEBUG ("removing pad %s:%s", GST_DEBUG_PAD_NAME (pad)); GST_COLLECT_PADS_PAD_LOCK (pads); list = g_slist_find_custom (pads->pad_list, pad, (GCompareFunc) find_pad); if (!list) goto unknown_pad; data = (GstCollectData *) list->data; GST_DEBUG ("found pad %s:%s at %p", GST_DEBUG_PAD_NAME (pad), data); /* clear the stuff we configured */ gst_pad_set_chain_function (pad, NULL); gst_pad_set_event_function (pad, NULL); GST_OBJECT_LOCK (pad); gst_pad_set_element_private (pad, NULL); GST_OBJECT_UNLOCK (pad); /* backward compat, also remove from data if stopped, note that this function * can only be called when we are stopped because we don't take the LOCK to * protect the pads->data list. */ if (!pads->started) { GSList *dlist; dlist = g_slist_find_custom (pads->data, pad, (GCompareFunc) find_pad); if (dlist) { GstCollectData *pdata = dlist->data; pads->data = g_slist_delete_link (pads->data, dlist); unref_data (pdata); } } /* remove from the pad list */ pads->pad_list = g_slist_delete_link (pads->pad_list, list); pads->pad_cookie++; /* signal waiters because something changed */ GST_COLLECT_PADS_BROADCAST (pads); /* deactivate the pad when needed */ if (!pads->started) gst_pad_set_active (pad, FALSE); /* clean and free the collect data */ unref_data (data); GST_COLLECT_PADS_PAD_UNLOCK (pads); return TRUE; unknown_pad: { GST_WARNING ("cannot remove unknown pad %s:%s", GST_DEBUG_PAD_NAME (pad)); GST_COLLECT_PADS_PAD_UNLOCK (pads); return FALSE; } } /** * gst_collect_pads_is_active: * @pads: (transfer none): the collectspads to use * @pad: the pad to check * * Check if a pad is active. * * This function is currently not implemented. * * MT safe. * * Returns: %TRUE if the pad is active. */ gboolean gst_collect_pads_is_active (GstCollectPads * pads, GstPad * pad) { g_return_val_if_fail (pads != NULL, FALSE); g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), FALSE); g_return_val_if_fail (pad != NULL, FALSE); g_return_val_if_fail (GST_IS_PAD (pad), FALSE); g_warning ("gst_collect_pads_is_active() is not implemented"); return FALSE; } /** * gst_collect_pads_collect: * @pads: the collectspads to use * * Collect data on all pads. This function is usually called * from a #GstTask function in an element. * * This function is currently not implemented. * * MT safe. * * Returns: #GstFlowReturn of the operation. */ GstFlowReturn gst_collect_pads_collect (GstCollectPads * pads) { g_return_val_if_fail (pads != NULL, GST_FLOW_ERROR); g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), GST_FLOW_ERROR); g_warning ("gst_collect_pads_collect() is not implemented"); return GST_FLOW_NOT_SUPPORTED; } /** * gst_collect_pads_collect_range: * @pads: the collectspads to use * @offset: the offset to collect * @length: the length to collect * * Collect data with @offset and @length on all pads. This function * is typically called in the getrange function of an element. * * This function is currently not implemented. * * MT safe. * * Returns: #GstFlowReturn of the operation. */ GstFlowReturn gst_collect_pads_collect_range (GstCollectPads * pads, guint64 offset, guint length) { g_return_val_if_fail (pads != NULL, GST_FLOW_ERROR); g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), GST_FLOW_ERROR); g_warning ("gst_collect_pads_collect_range() is not implemented"); return GST_FLOW_NOT_SUPPORTED; } static gboolean gst_collect_pads_is_flushing (GstCollectPads * pads) { GSList *walk = NULL; gboolean res = TRUE; GST_COLLECT_PADS_PAD_LOCK (pads); /* Ensure pads->data state */ gst_collect_pads_check_pads_unlocked (pads); GST_DEBUG ("Getting flushing state (pads:%p, pads->data:%p)", pads, pads->data); for (walk = pads->data; walk; walk = g_slist_next (walk)) { GstCollectData *cdata = walk->data; GST_DEBUG_OBJECT (cdata->pad, "flushing:%d", cdata->flushing); if (cdata->flushing) { goto done; } } res = FALSE; done: GST_COLLECT_PADS_PAD_UNLOCK (pads); return res; } /* FIXME, I think this function is used to work around bad behaviour * of elements that add pads to themselves without activating them. * * Must be called with PAD_LOCK. */ static void gst_collect_pads_set_flushing_unlocked (GstCollectPads * pads, gboolean flushing) { GSList *walk = NULL; GST_DEBUG ("Setting flushing (%d)", flushing); /* Update the pads flushing flag */ for (walk = pads->data; walk; walk = g_slist_next (walk)) { GstCollectData *cdata = walk->data; if (GST_IS_PAD (cdata->pad)) { GST_OBJECT_LOCK (cdata->pad); if (flushing) GST_PAD_SET_FLUSHING (cdata->pad); else GST_PAD_UNSET_FLUSHING (cdata->pad); cdata->flushing = flushing; gst_collect_pads_clear (pads, cdata); GST_OBJECT_UNLOCK (cdata->pad); } } /* Setting the pads to flushing means that we changed the values which * are 'protected' by the cookie. We therefore update it to force a * recalculation of the current pad status. */ pads->pad_cookie++; } /** * gst_collect_pads_set_flushing: * @pads: the collectspads to use * @flushing: desired state of the pads * * Change the flushing state of all the pads in the collection. No pad * is able to accept anymore data when @flushing is %TRUE. Calling this * function with @flushing %FALSE makes @pads accept data again. * * MT safe. * * Since: 0.10.7. */ void gst_collect_pads_set_flushing (GstCollectPads * pads, gboolean flushing) { g_return_if_fail (pads != NULL); g_return_if_fail (GST_IS_COLLECT_PADS (pads)); GST_COLLECT_PADS_PAD_LOCK (pads); /* Ensure pads->data state */ gst_collect_pads_check_pads_unlocked (pads); gst_collect_pads_set_flushing_unlocked (pads, flushing); GST_COLLECT_PADS_PAD_UNLOCK (pads); } /** * gst_collect_pads_start: * @pads: the collectspads to use * * Starts the processing of data in the collect_pads. * * MT safe. */ void gst_collect_pads_start (GstCollectPads * pads) { GSList *collected; g_return_if_fail (pads != NULL); g_return_if_fail (GST_IS_COLLECT_PADS (pads)); GST_DEBUG_OBJECT (pads, "starting collect pads"); /* make sure stop and collect cannot be called anymore */ GST_OBJECT_LOCK (pads); /* make pads streamable */ GST_COLLECT_PADS_PAD_LOCK (pads); /* loop over the master pad list and reset the segment */ collected = pads->pad_list; for (; collected; collected = g_slist_next (collected)) { GstCollectData *data; data = collected->data; gst_segment_init (&data->segment, GST_FORMAT_UNDEFINED); } gst_collect_pads_set_flushing_unlocked (pads, FALSE); /* Start collect pads */ pads->started = TRUE; GST_COLLECT_PADS_PAD_UNLOCK (pads); GST_OBJECT_UNLOCK (pads); } /** * gst_collect_pads_stop: * @pads: the collectspads to use * * Stops the processing of data in the collect_pads. this function * will also unblock any blocking operations. * * MT safe. */ void gst_collect_pads_stop (GstCollectPads * pads) { GSList *collected; g_return_if_fail (pads != NULL); g_return_if_fail (GST_IS_COLLECT_PADS (pads)); GST_DEBUG_OBJECT (pads, "stopping collect pads"); /* make sure collect and start cannot be called anymore */ GST_OBJECT_LOCK (pads); /* make pads not accept data anymore */ GST_COLLECT_PADS_PAD_LOCK (pads); gst_collect_pads_set_flushing_unlocked (pads, TRUE); /* Stop collect pads */ pads->started = FALSE; pads->eospads = 0; pads->queuedpads = 0; /* loop over the master pad list and flush buffers */ collected = pads->pad_list; for (; collected; collected = g_slist_next (collected)) { GstCollectData *data; GstBuffer **buffer_p; data = collected->data; if (data->buffer) { buffer_p = &data->buffer; gst_buffer_replace (buffer_p, NULL); data->pos = 0; } data->eos = FALSE; } GST_COLLECT_PADS_PAD_UNLOCK (pads); /* Wake them up so they can end the chain functions. */ GST_COLLECT_PADS_BROADCAST (pads); GST_OBJECT_UNLOCK (pads); } /** * gst_collect_pads_peek: * @pads: the collectspads to peek * @data: the data to use * * Peek at the buffer currently queued in @data. This function * should be called with the @pads LOCK held, such as in the callback * handler. * * MT safe. * * Returns: (transfer full): The buffer in @data or NULL if no buffer is queued. * should unref the buffer after usage. */ GstBuffer * gst_collect_pads_peek (GstCollectPads * pads, GstCollectData * data) { GstBuffer *result; g_return_val_if_fail (pads != NULL, NULL); g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), NULL); g_return_val_if_fail (data != NULL, NULL); if ((result = data->buffer)) gst_buffer_ref (result); GST_DEBUG ("Peeking at pad %s:%s: buffer=%p", GST_DEBUG_PAD_NAME (data->pad), result); return result; } /** * gst_collect_pads_pop: * @pads: the collectspads to pop * @data: the data to use * * Pop the buffer currently queued in @data. This function * should be called with the @pads LOCK held, such as in the callback * handler. * * Free-function: gst_buffer_unref * * MT safe. * * Returns: (transfer full): The buffer in @data or NULL if no buffer was * queued. You should unref the buffer after usage. */ GstBuffer * gst_collect_pads_pop (GstCollectPads * pads, GstCollectData * data) { GstBuffer *result; g_return_val_if_fail (pads != NULL, NULL); g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), NULL); g_return_val_if_fail (data != NULL, NULL); if ((result = data->buffer)) { data->buffer = NULL; data->pos = 0; /* one less pad with queued data now */ pads->queuedpads--; } GST_COLLECT_PADS_BROADCAST (pads); GST_DEBUG ("Pop buffer on pad %s:%s: buffer=%p", GST_DEBUG_PAD_NAME (data->pad), result); return result; } /* pop and unref the currently queued buffer, should e called with the LOCK * helt. */ static void gst_collect_pads_clear (GstCollectPads * pads, GstCollectData * data) { GstBuffer *buf; if ((buf = gst_collect_pads_pop (pads, data))) gst_buffer_unref (buf); } /** * gst_collect_pads_available: * @pads: the collectspads to query * * Query how much bytes can be read from each queued buffer. This means * that the result of this call is the maximum number of bytes that can * be read from each of the pads. * * This function should be called with @pads LOCK held, such as * in the callback. * * MT safe. * * Returns: The maximum number of bytes queued on all pads. This function * returns 0 if a pad has no queued buffer. */ /* FIXME, we can do this in the _chain functions */ guint gst_collect_pads_available (GstCollectPads * pads) { GSList *collected; guint result = G_MAXUINT; g_return_val_if_fail (pads != NULL, 0); g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), 0); for (collected = pads->data; collected; collected = g_slist_next (collected)) { GstCollectData *pdata; GstBuffer *buffer; gint size; pdata = (GstCollectData *) collected->data; /* ignore pad with EOS */ if (G_UNLIKELY (pdata->eos)) { GST_DEBUG ("pad %s:%s is EOS", GST_DEBUG_PAD_NAME (pdata->pad)); continue; } /* an empty buffer without EOS is weird when we get here.. */ if (G_UNLIKELY ((buffer = pdata->buffer) == NULL)) { GST_WARNING ("pad %s:%s has no buffer", GST_DEBUG_PAD_NAME (pdata->pad)); goto not_filled; } /* this is the size left of the buffer */ size = gst_buffer_get_size (buffer) - pdata->pos; GST_DEBUG ("pad %s:%s has %d bytes left", GST_DEBUG_PAD_NAME (pdata->pad), size); /* need to return the min of all available data */ if (size < result) result = size; } /* nothing changed, all must be EOS then, return 0 */ if (G_UNLIKELY (result == G_MAXUINT)) result = 0; return result; not_filled: { return 0; } } /** * gst_collect_pads_read_buffer: * @pads: the collectspads to query * @data: the data to use * @size: the number of bytes to read * * Get a buffer of @size bytes from the given pad @data. * * This function should be called with @pads LOCK held, such as in the callback. * * Free-function: gst_buffer_unref * * Returns: (transfer full): a #GstBuffer. The size of the buffer can be less * that requested. A return of NULL signals that the pad is end-of-stream. * Unref the buffer with gst_buffer_unref() after use. * * MT safe. * * Since: 0.10.18 */ GstBuffer * gst_collect_pads_read_buffer (GstCollectPads * pads, GstCollectData * data, guint size) { guint readsize, bufsize; GstBuffer *buffer; g_return_val_if_fail (pads != NULL, NULL); g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), NULL); g_return_val_if_fail (data != NULL, NULL); /* no buffer, must be EOS */ if ((buffer = data->buffer) == NULL) return NULL; bufsize = gst_buffer_get_size (buffer); readsize = MIN (size, bufsize - data->pos); if (data->pos == 0 && readsize == bufsize) return gst_buffer_ref (buffer); else return gst_buffer_copy_region (buffer, GST_BUFFER_COPY_ALL, data->pos, readsize); } /** * gst_collect_pads_take_buffer: * @pads: the collectspads to query * @data: the data to use * @size: the number of bytes to read * * Get a buffer of @size bytes from the given pad @data. Flushes the amount * of read bytes. * * This function should be called with @pads LOCK held, such as in the callback. * * Free-function: gst_buffer_unref * * MT safe. * * Returns: (transfer full): a #GstBuffer. The size of the buffer can be less * that requested. A return of NULL signals that the pad is end-of-stream. * Unref the buffer after use. * * Since: 0.10.18 */ GstBuffer * gst_collect_pads_take_buffer (GstCollectPads * pads, GstCollectData * data, guint size) { GstBuffer *buffer = gst_collect_pads_read_buffer (pads, data, size); if (buffer) { gst_collect_pads_flush (pads, data, gst_buffer_get_size (buffer)); } return buffer; } /** * gst_collect_pads_flush: * @pads: the collectspads to query * @data: the data to use * @size: the number of bytes to flush * * Flush @size bytes from the pad @data. * * This function should be called with @pads LOCK held, such as * in the callback. * * MT safe. * * Returns: The number of bytes flushed. This can be less than @size and * is 0 if the pad was end-of-stream. */ guint gst_collect_pads_flush (GstCollectPads * pads, GstCollectData * data, guint size) { guint flushsize; GstBuffer *buffer; gsize bsize; g_return_val_if_fail (pads != NULL, 0); g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), 0); g_return_val_if_fail (data != NULL, 0); /* no buffer, must be EOS */ if ((buffer = data->buffer) == NULL) return 0; bsize = gst_buffer_get_size (buffer); /* this is what we can flush at max */ flushsize = MIN (size, bsize - data->pos); data->pos += size; GST_LOG_OBJECT (pads, "Flushing %d bytes, requested %u", flushsize, size); if (data->pos >= bsize) /* _clear will also reset data->pos to 0 */ gst_collect_pads_clear (pads, data); return flushsize; } /* see if pads were added or removed and update our stats. Any pad * added after releasing the PAD_LOCK will get collected in the next * round. * * We can do a quick check by checking the cookies, that get changed * whenever the pad list is updated. * * Must be called with LOCK. */ static void gst_collect_pads_check_pads_unlocked (GstCollectPads * pads) { GST_DEBUG ("stored cookie : %d, used_cookie:%d", pads->pad_cookie, pads->cookie); if (G_UNLIKELY (pads->pad_cookie != pads->cookie)) { GSList *collected; /* clear list and stats */ g_slist_foreach (pads->data, (GFunc) unref_data, NULL); g_slist_free (pads->data); pads->data = NULL; pads->numpads = 0; pads->queuedpads = 0; pads->eospads = 0; /* loop over the master pad list */ collected = pads->pad_list; for (; collected; collected = g_slist_next (collected)) { GstCollectData *data; /* update the stats */ pads->numpads++; data = collected->data; if (G_LIKELY (!data->flushing)) { if (data->buffer) pads->queuedpads++; if (data->eos) pads->eospads++; } /* add to the list of pads to collect */ ref_data (data); pads->data = g_slist_prepend (pads->data, data); } /* and update the cookie */ pads->cookie = pads->pad_cookie; } } static inline void gst_collect_pads_check_pads (GstCollectPads * pads) { /* the master list and cookie are protected with the PAD_LOCK */ GST_COLLECT_PADS_PAD_LOCK (pads); gst_collect_pads_check_pads_unlocked (pads); GST_COLLECT_PADS_PAD_UNLOCK (pads); } /* checks if all the pads are collected and call the collectfunction * * Should be called with LOCK. * * Returns: The #GstFlowReturn of collection. */ static GstFlowReturn gst_collect_pads_check_collected (GstCollectPads * pads) { GstFlowReturn flow_ret = GST_FLOW_OK; g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), GST_FLOW_ERROR); g_return_val_if_fail (pads->func != NULL, GST_FLOW_NOT_SUPPORTED); /* check for new pads, update stats etc.. */ gst_collect_pads_check_pads (pads); if (G_UNLIKELY (pads->eospads == pads->numpads)) { /* If all our pads are EOS just collect once to let the element * do its final EOS handling. */ GST_DEBUG ("All active pads (%d) are EOS, calling %s", pads->numpads, GST_DEBUG_FUNCPTR_NAME (pads->func)); flow_ret = pads->func (pads, pads->user_data); } else { gboolean collected = FALSE; /* We call the collected function as long as our condition matches. * FIXME: should we error out if the collect function did not pop anything ? * we can get a busy loop here if the element does not pop from the collect * function */ while (((pads->queuedpads + pads->eospads) >= pads->numpads)) { GST_DEBUG ("All active pads (%d + %d >= %d) have data, calling %s", pads->queuedpads, pads->eospads, pads->numpads, GST_DEBUG_FUNCPTR_NAME (pads->func)); flow_ret = pads->func (pads, pads->user_data); collected = TRUE; /* break on error */ if (flow_ret != GST_FLOW_OK) break; /* Don't keep looping after telling the element EOS or flushing */ if (pads->queuedpads == 0) break; } if (!collected) GST_DEBUG ("Not all active pads (%d) have data, continuing", pads->numpads); } return flow_ret; } static gboolean gst_collect_pads_event (GstPad * pad, GstObject * parent, GstEvent * event) { gboolean res; GstCollectData *data; GstCollectPads *pads; /* some magic to get the managing collect_pads */ GST_OBJECT_LOCK (pad); data = (GstCollectData *) gst_pad_get_element_private (pad); if (G_UNLIKELY (data == NULL)) goto pad_removed; ref_data (data); GST_OBJECT_UNLOCK (pad); res = TRUE; pads = data->collect; GST_DEBUG ("Got %s event on pad %s:%s", GST_EVENT_TYPE_NAME (event), GST_DEBUG_PAD_NAME (data->pad)); switch (GST_EVENT_TYPE (event)) { case GST_EVENT_FLUSH_START: { /* forward event to unblock check_collected */ gst_pad_event_default (pad, parent, event); /* now unblock the chain function. * no cond per pad, so they all unblock, * non-flushing block again */ GST_OBJECT_LOCK (pads); data->flushing = TRUE; gst_collect_pads_clear (pads, data); GST_OBJECT_UNLOCK (pads); /* event already cleaned up by forwarding */ goto done; } case GST_EVENT_FLUSH_STOP: { /* flush the 1 buffer queue */ GST_OBJECT_LOCK (pads); data->flushing = FALSE; gst_collect_pads_clear (pads, data); /* we need new segment info after the flush */ gst_segment_init (&data->segment, GST_FORMAT_UNDEFINED); data->new_segment = FALSE; /* if the pad was EOS, remove the EOS flag and * decrement the number of eospads */ if (G_UNLIKELY (data->eos == TRUE)) { pads->eospads--; data->eos = FALSE; } if (!gst_collect_pads_is_flushing (pads)) { /* forward event if all pads are no longer flushing */ GST_DEBUG ("No more pads are flushing, forwarding FLUSH_STOP"); GST_OBJECT_UNLOCK (pads); goto forward; } gst_event_unref (event); GST_OBJECT_UNLOCK (pads); goto done; } case GST_EVENT_EOS: { GST_OBJECT_LOCK (pads); /* if the pad was not EOS, make it EOS and so we * have one more eospad */ if (G_LIKELY (data->eos == FALSE)) { data->eos = TRUE; pads->eospads++; } /* check if we need collecting anything, we ignore the * result. */ gst_collect_pads_check_collected (pads); GST_OBJECT_UNLOCK (pads); /* We eat this event, element should do something * in the collected callback. */ gst_event_unref (event); goto done; } case GST_EVENT_SEGMENT: { gst_event_copy_segment (event, &data->segment); GST_DEBUG_OBJECT (data->pad, "got newsegment %" GST_SEGMENT_FORMAT, &data->segment); data->new_segment = TRUE; /* we must not forward this event since multiple segments will be * accumulated and this is certainly not what we want. */ gst_event_unref (event); /* FIXME: collect-pads based elements need to create their own newsegment * event (and only one really) * (a) make the segment part of the GstCollectData structure of each pad, * so you can just check that once you have a buffer queued on that pad, * (b) you can override a pad's event function with your own, * catch the newsegment event and then pass it on to the original * gstcollectpads event function * (that's what avimux does for something IIRC) * see #340060 */ goto done; } default: /* forward other events */ goto forward; } forward: GST_DEBUG_OBJECT (pads, "forward unhandled event: %s", GST_EVENT_TYPE_NAME (event)); res = gst_pad_event_default (pad, parent, event); done: unref_data (data); return res; /* ERRORS */ pad_removed: { GST_DEBUG ("%s got removed from collectpads", GST_OBJECT_NAME (pad)); GST_OBJECT_UNLOCK (pad); return FALSE; } } /* For each buffer we receive we check if our collected condition is reached * and if so we call the collected function. When this is done we check if * data has been unqueued. If data is still queued we wait holding the stream * lock to make sure no EOS event can happen while we are ready to be * collected */ static GstFlowReturn gst_collect_pads_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer) { GstCollectData *data; GstCollectPads *pads; GstCollectPadsPrivate *priv; GstFlowReturn ret; GST_DEBUG ("Got buffer for pad %s:%s", GST_DEBUG_PAD_NAME (pad)); /* some magic to get the managing collect_pads */ GST_OBJECT_LOCK (pad); data = (GstCollectData *) gst_pad_get_element_private (pad); if (G_UNLIKELY (data == NULL)) goto no_data; ref_data (data); GST_OBJECT_UNLOCK (pad); pads = data->collect; priv = pads->priv; GST_OBJECT_LOCK (pads); /* if not started, bail out */ if (G_UNLIKELY (!pads->started)) goto not_started; /* check if this pad is flushing */ if (G_UNLIKELY (data->flushing)) goto flushing; /* pad was EOS, we can refuse this data */ if (G_UNLIKELY (data->eos)) goto unexpected; /* see if we need to clip */ if (priv->clipfunc) { buffer = priv->clipfunc (pads, data, buffer, priv->clipfunc_user_data); if (G_UNLIKELY (buffer == NULL)) goto clipped; } GST_DEBUG ("Queuing buffer %p for pad %s:%s", buffer, GST_DEBUG_PAD_NAME (pad)); /* One more pad has data queued */ pads->queuedpads++; /* take ownership of the buffer */ if (data->buffer) gst_buffer_unref (data->buffer); data->buffer = buffer; buffer = NULL; /* update segment last position if in TIME */ if (G_LIKELY (data->segment.format == GST_FORMAT_TIME)) { GstClockTime timestamp = GST_BUFFER_TIMESTAMP (data->buffer); if (GST_CLOCK_TIME_IS_VALID (timestamp)) data->segment.position = timestamp; } /* While we have data queued on this pad try to collect stuff */ do { GST_DEBUG ("Pad %s:%s checking", GST_DEBUG_PAD_NAME (pad)); /* Check if our collected condition is matched and call the collected function * if it is */ ret = gst_collect_pads_check_collected (pads); /* when an error occurs, we want to report this back to the caller ASAP * without having to block if the buffer was not popped */ if (G_UNLIKELY (ret != GST_FLOW_OK)) goto error; /* data was consumed, we can exit and accept new data */ if (data->buffer == NULL) break; /* Check if we got removed in the mean time, FIXME, this is racy. * Between this check and the _WAIT, the pad could be removed which will * makes us hang in the _WAIT. */ GST_OBJECT_LOCK (pad); if (G_UNLIKELY (gst_pad_get_element_private (pad) == NULL)) goto pad_removed; GST_OBJECT_UNLOCK (pad); GST_DEBUG ("Pad %s:%s has a buffer queued, waiting", GST_DEBUG_PAD_NAME (pad)); /* wait to be collected, this must happen from another thread triggered * by the _chain function of another pad. We release the lock so we * can get stopped or flushed as well. We can however not get EOS * because we still hold the STREAM_LOCK. */ GST_COLLECT_PADS_WAIT (pads); GST_DEBUG ("Pad %s:%s resuming", GST_DEBUG_PAD_NAME (pad)); /* after a signal, we could be stopped */ if (G_UNLIKELY (!pads->started)) goto not_started; /* check if this pad is flushing */ if (G_UNLIKELY (data->flushing)) goto flushing; } while (data->buffer != NULL); unlock_done: GST_DEBUG ("Pad %s:%s done", GST_DEBUG_PAD_NAME (pad)); GST_OBJECT_UNLOCK (pads); unref_data (data); if (buffer) gst_buffer_unref (buffer); return ret; pad_removed: { GST_WARNING ("%s got removed from collectpads", GST_OBJECT_NAME (pad)); GST_OBJECT_UNLOCK (pad); ret = GST_FLOW_NOT_LINKED; goto unlock_done; } /* ERRORS */ no_data: { GST_DEBUG ("%s got removed from collectpads", GST_OBJECT_NAME (pad)); GST_OBJECT_UNLOCK (pad); gst_buffer_unref (buffer); return GST_FLOW_NOT_LINKED; } not_started: { GST_DEBUG ("not started"); gst_collect_pads_clear (pads, data); ret = GST_FLOW_WRONG_STATE; goto unlock_done; } flushing: { GST_DEBUG ("pad %s:%s is flushing", GST_DEBUG_PAD_NAME (pad)); gst_collect_pads_clear (pads, data); ret = GST_FLOW_WRONG_STATE; goto unlock_done; } unexpected: { /* we should not post an error for this, just inform upstream that * we don't expect anything anymore */ GST_DEBUG ("pad %s:%s is eos", GST_DEBUG_PAD_NAME (pad)); ret = GST_FLOW_EOS; goto unlock_done; } clipped: { GST_DEBUG ("clipped buffer on pad %s:%s", GST_DEBUG_PAD_NAME (pad)); ret = GST_FLOW_OK; goto unlock_done; } error: { /* we print the error, the element should post a reasonable error * message for fatal errors */ GST_DEBUG ("collect failed, reason %d (%s)", ret, gst_flow_get_name (ret)); gst_collect_pads_clear (pads, data); goto unlock_done; } }