2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
25 #include "gstfilesrc.h"
36 /**********************************************************************
37 * GStreamer Default File Source
40 * This source uses mmap(2) to efficiently load data from a file.
41 * To do this without seriously polluting the applications' memory
42 * space, it must do so in smaller chunks, say 1-4MB at a time.
43 * Buffers are then subdivided from these mmap'd chunks, to directly
44 * make use of the mmap.
46 * To handle refcounting so that the mmap can be freed at the appropriate
47 * time, a buffer will be created for each mmap'd region, and all new
48 * buffers will be sub-buffers of this top-level buffer. As they are
49 * freed, the refcount goes down on the mmap'd buffer and its free()
50 * function is called, which will call munmap(2) on itself.
52 * If a buffer happens to cross the boundaries of an mmap'd region, we
53 * have to decide whether it's more efficient to copy the data into a
54 * new buffer, or mmap() just that buffer. There will have to be a
55 * breakpoint size to determine which will be done. The mmap() size
56 * has a lot to do with this as well, because you end up in double-
57 * jeopardy: the larger the outgoing buffer, the more data to copy when
58 * it overlaps, *and* the more frequently you'll have buffers that *do*
61 * Seeking is another tricky aspect to do efficiently. The initial
62 * implementation of this source won't make use of these features, however.
63 * The issue is that if an application seeks backwards in a file, *and*
64 * that region of the file is covered by an mmap that hasn't been fully
65 * deallocated, we really should re-use it. But keeping track of these
66 * regions is tricky because we have to lock the structure that holds
67 * them. We need to settle on a locking primitive (GMutex seems to be
68 * a really good option...), then we can do that.
72 GstElementDetails gst_filesrc_details = {
76 "Read from arbitrary point in a file",
78 "Erik Walthinsen <omega@cse.ogi.edu>",
82 /* #define fs_print(format,args...) g_print(format, ## args) */
83 #define fs_print(format,args...)
85 /* FileSrc signals and args */
100 GST_EVENT_MASK_FUNCTION (gst_filesrc_get_event_mask,
101 { GST_EVENT_SEEK, GST_SEEK_METHOD_CUR |
102 GST_SEEK_METHOD_SET |
103 GST_SEEK_METHOD_END |
104 GST_SEEK_FLAG_FLUSH },
105 { GST_EVENT_FLUSH, 0 },
106 { GST_EVENT_SIZE, 0 }
109 GST_PAD_QUERY_TYPE_FUNCTION (gst_filesrc_get_query_types,
111 GST_PAD_QUERY_POSITION
114 GST_FORMATS_FUNCTION (gst_filesrc_get_formats,
118 static void gst_filesrc_class_init (GstFileSrcClass *klass);
119 static void gst_filesrc_init (GstFileSrc *filesrc);
120 static void gst_filesrc_dispose (GObject *object);
122 static void gst_filesrc_set_property (GObject *object, guint prop_id,
123 const GValue *value, GParamSpec *pspec);
124 static void gst_filesrc_get_property (GObject *object, guint prop_id,
125 GValue *value, GParamSpec *pspec);
127 static GstBuffer * gst_filesrc_get (GstPad *pad);
128 static gboolean gst_filesrc_srcpad_event (GstPad *pad, GstEvent *event);
129 static gboolean gst_filesrc_srcpad_query (GstPad *pad, GstPadQueryType type,
130 GstFormat *format, gint64 *value);
132 static GstElementStateReturn gst_filesrc_change_state (GstElement *element);
135 static GstElementClass *parent_class = NULL;
136 /*static guint gst_filesrc_signals[LAST_SIGNAL] = { 0 };*/
139 gst_filesrc_get_type(void)
141 static GType filesrc_type = 0;
144 static const GTypeInfo filesrc_info = {
145 sizeof(GstFileSrcClass), NULL,
147 (GClassInitFunc)gst_filesrc_class_init,
152 (GInstanceInitFunc)gst_filesrc_init,
154 filesrc_type = g_type_register_static (GST_TYPE_ELEMENT, "GstFileSrc", &filesrc_info, 0);
160 gst_filesrc_class_init (GstFileSrcClass *klass)
162 GObjectClass *gobject_class;
163 GstElementClass *gstelement_class;
165 gobject_class = (GObjectClass*)klass;
166 gstelement_class = (GstElementClass*)klass;
168 parent_class = g_type_class_ref (GST_TYPE_ELEMENT);
170 gst_element_class_install_std_props (
171 GST_ELEMENT_CLASS (klass),
172 "fd", ARG_FD, G_PARAM_READABLE,
173 "location", ARG_LOCATION, G_PARAM_READWRITE,
174 "blocksize", ARG_BLOCKSIZE, G_PARAM_READWRITE,
175 "mmapsize", ARG_MAPSIZE, G_PARAM_READWRITE,
176 "touch", ARG_TOUCH, G_PARAM_READWRITE,
179 gobject_class->dispose = gst_filesrc_dispose;
180 gobject_class->set_property = gst_filesrc_set_property;
181 gobject_class->get_property = gst_filesrc_get_property;
183 gstelement_class->change_state = gst_filesrc_change_state;
187 gst_filesrc_bufcmp (gconstpointer a, gconstpointer b)
189 /* GstBuffer *bufa = (GstBuffer *)a, *bufb = (GstBuffer *)b;*/
191 /* sort first by offset, then in reverse by size */
192 if (GST_BUFFER_OFFSET(a) < GST_BUFFER_OFFSET(b)) return -1;
193 else if (GST_BUFFER_OFFSET(a) > GST_BUFFER_OFFSET(b)) return 1;
194 else if (GST_BUFFER_SIZE(a) > GST_BUFFER_SIZE(b)) return -1;
195 else if (GST_BUFFER_SIZE(a) < GST_BUFFER_SIZE(b)) return 1;
200 gst_filesrc_init (GstFileSrc *src)
202 src->srcpad = gst_pad_new ("src", GST_PAD_SRC);
203 gst_pad_set_get_function (src->srcpad, gst_filesrc_get);
204 gst_pad_set_event_function (src->srcpad, gst_filesrc_srcpad_event);
205 gst_pad_set_event_mask_function (src->srcpad, gst_filesrc_get_event_mask);
206 gst_pad_set_query_function (src->srcpad, gst_filesrc_srcpad_query);
207 gst_pad_set_query_type_function (src->srcpad, gst_filesrc_get_query_types);
208 gst_pad_set_formats_function (src->srcpad, gst_filesrc_get_formats);
209 gst_element_add_pad (GST_ELEMENT (src), src->srcpad);
211 src->pagesize = getpagesize();
213 src->filename = NULL;
218 src->block_size = 4096;
222 src->mapsize = 4 * 1024 * 1024; /* default is 4MB */
224 src->map_regions = g_tree_new (gst_filesrc_bufcmp);
225 src->map_regions_lock = g_mutex_new();
227 src->seek_happened = FALSE;
231 gst_filesrc_dispose (GObject *object)
235 src = GST_FILESRC (object);
237 G_OBJECT_CLASS (parent_class)->dispose (object);
239 g_tree_destroy (src->map_regions);
240 g_mutex_free (src->map_regions_lock);
242 g_free (src->filename);
247 gst_filesrc_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
251 /* it's not null if we got it, but it might not be ours */
252 g_return_if_fail (GST_IS_FILESRC (object));
254 src = GST_FILESRC (object);
258 /* the element must be stopped in order to do this */
259 g_return_if_fail (GST_STATE (src) < GST_STATE_PLAYING);
261 if (src->filename) g_free (src->filename);
262 /* clear the filename if we get a NULL (is that possible?) */
263 if (g_value_get_string (value) == NULL) {
264 gst_element_set_state (GST_ELEMENT (object), GST_STATE_NULL);
265 src->filename = NULL;
266 /* otherwise set the new filename */
268 src->filename = g_strdup (g_value_get_string (value));
270 g_object_notify (G_OBJECT (src), "location");
273 src->block_size = g_value_get_ulong (value);
274 g_object_notify (G_OBJECT (src), "blocksize");
277 if ((src->mapsize % src->pagesize) == 0) {
278 src->mapsize = g_value_get_ulong (value);
279 g_object_notify (G_OBJECT (src), "mmapsize");
281 GST_INFO(0, "invalid mapsize, must a multiple of pagesize, which is %d\n",src->pagesize);
285 src->touch = g_value_get_boolean (value);
286 g_object_notify (G_OBJECT (src), "touch");
294 gst_filesrc_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
298 /* it's not null if we got it, but it might not be ours */
299 g_return_if_fail (GST_IS_FILESRC (object));
301 src = GST_FILESRC (object);
305 g_value_set_string (value, src->filename);
308 g_value_set_int (value, src->fd);
311 g_value_set_ulong (value, src->block_size);
314 g_value_set_ulong (value, src->mapsize);
317 g_value_set_boolean (value, src->touch);
320 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
326 gst_filesrc_free_parent_mmap (GstBuffer *buf)
328 GstFileSrc *src = GST_FILESRC(GST_BUFFER_POOL_PRIVATE(buf));
330 fs_print ("freeing mmap()d buffer at %d+%d\n",GST_BUFFER_OFFSET(buf),GST_BUFFER_SIZE(buf));
332 /* remove the buffer from the list of available mmap'd regions */
333 g_mutex_lock(src->map_regions_lock);
334 g_tree_remove(src->map_regions,buf);
335 /* check to see if the tree is empty */
336 if (g_tree_nnodes(src->map_regions) == 0) {
337 /* we have to free the bufferpool we don't have yet */
339 g_mutex_unlock(src->map_regions_lock);
342 /* madvise to tell the kernel what to do with it */
343 madvise(GST_BUFFER_DATA(buf),GST_BUFFER_SIZE(buf),MADV_DONTNEED);
345 /* now unmap the memory */
346 munmap(GST_BUFFER_DATA(buf),GST_BUFFER_MAXSIZE(buf));
348 GST_BUFFER_DATA (buf) = NULL;
350 gst_buffer_default_free (buf);
354 gst_filesrc_map_region (GstFileSrc *src, off_t offset, size_t size)
359 g_return_val_if_fail (offset >= 0, NULL);
361 fs_print ("mapping region %08llx+%08x from file into memory\n",offset,size);
363 /* time to allocate a new mapbuf */
364 buf = gst_buffer_new();
365 /* mmap() the data into this new buffer */
366 GST_BUFFER_DATA(buf) = mmap (NULL, size, PROT_READ, MAP_SHARED, src->fd, offset);
367 if (GST_BUFFER_DATA(buf) == NULL) {
368 gst_element_error (GST_ELEMENT (src), "couldn't map file");
369 } else if (GST_BUFFER_DATA(buf) == MAP_FAILED) {
370 gst_element_error (GST_ELEMENT (src), "mmap (0x%x, %d, 0x%llx) : %s",
371 size, src->fd, offset, strerror (errno));
373 #ifdef MADV_SEQUENTIAL
374 /* madvise to tell the kernel what to do with it */
375 retval = madvise(GST_BUFFER_DATA(buf),GST_BUFFER_SIZE(buf),MADV_SEQUENTIAL);
377 /* fill in the rest of the fields */
378 GST_BUFFER_FLAG_SET(buf, GST_BUFFER_READONLY);
379 GST_BUFFER_FLAG_SET(buf, GST_BUFFER_ORIGINAL);
380 GST_BUFFER_SIZE(buf) = size;
381 GST_BUFFER_MAXSIZE(buf) = size;
382 GST_BUFFER_OFFSET(buf) = offset;
383 GST_BUFFER_TIMESTAMP(buf) = -1LL;
384 GST_BUFFER_POOL_PRIVATE(buf) = src;
385 GST_BUFFER_FREE_FUNC(buf) = (GstDataFreeFunction) gst_filesrc_free_parent_mmap;
387 g_mutex_lock(src->map_regions_lock);
388 g_tree_insert(src->map_regions,buf,buf);
389 g_mutex_unlock(src->map_regions_lock);
395 gst_filesrc_map_small_region (GstFileSrc *src, off_t offset, size_t size)
401 /* printf("attempting to map a small buffer at %d+%d\n",offset,size); */
403 /* if the offset starts at a non-page boundary, we have to special case */
404 if ((mod = offset % src->pagesize)) {
407 mapbase = offset - mod;
408 mapsize = ((size + mod + src->pagesize - 1) / src->pagesize) * src->pagesize;
409 /* printf("not on page boundaries, resizing map to %d+%d\n",mapbase,mapsize);*/
410 map = gst_filesrc_map_region(src, mapbase, mapsize);
411 ret = gst_buffer_create_sub (map, offset - mapbase, size);
413 gst_buffer_unref (map);
418 return gst_filesrc_map_region(src,offset,size);
426 /* This allows us to search for a potential mmap region. */
428 gst_filesrc_search_region_match (gpointer a, gpointer b)
430 GstFileSrcRegion *r = (GstFileSrcRegion *)b;
432 /* trying to walk b down the tree, current node is a */
433 if (r->offset < GST_BUFFER_OFFSET(a)) return -1;
434 else if (r->offset >= (GST_BUFFER_OFFSET(a) + GST_BUFFER_SIZE(a))) return 1;
435 else if ((r->offset + r->size) <= (GST_BUFFER_OFFSET(a) + GST_BUFFER_SIZE(a))) return 0;
442 * @pad: #GstPad to push a buffer from
444 * Push a new buffer from the filesrc at the current offset.
447 gst_filesrc_get (GstPad *pad)
450 GstBuffer *buf = NULL, *map;
452 off_t readend,mapstart,mapend;
453 GstFileSrcRegion region;
456 g_return_val_if_fail (pad != NULL, NULL);
457 src = GST_FILESRC (gst_pad_get_parent (pad));
458 g_return_val_if_fail (GST_FLAG_IS_SET (src, GST_FILESRC_OPEN), NULL);
461 if (src->seek_happened) {
464 src->seek_happened = FALSE;
465 GST_DEBUG (GST_CAT_EVENT, "filesrc sending discont\n");
466 event = gst_event_new_discontinuous (FALSE, GST_FORMAT_BYTES, src->curoffset, NULL);
467 GST_EVENT_DISCONT_NEW_MEDIA (event) = FALSE;
468 src->need_flush = FALSE;
469 return GST_BUFFER (event);
471 /* check for flush */
472 if (src->need_flush) {
473 src->need_flush = FALSE;
474 GST_DEBUG (GST_CAT_EVENT, "filesrc sending flush\n");
475 return GST_BUFFER (gst_event_new_flush ());
479 if (src->curoffset == src->filelen) {
480 GST_DEBUG (0, "filesrc eos %lld %lld\n", src->curoffset, src->filelen);
481 gst_element_set_eos (GST_ELEMENT (src));
482 return GST_BUFFER (gst_event_new (GST_EVENT_EOS));
485 /* calculate end pointers so we don't have to do so repeatedly later */
486 readsize = src->block_size;
487 readend = src->curoffset + src->block_size; /* note this is the byte *after* the read */
488 mapstart = GST_BUFFER_OFFSET(src->mapbuf);
489 mapend = mapstart + GST_BUFFER_SIZE(src->mapbuf); /* note this is the byte *after* the map */
491 /* check to see if we're going to overflow the end of the file */
492 if (readend > src->filelen) {
493 readsize = src->filelen - src->curoffset;
494 readend = src->curoffset + readsize;
497 /* if the start is past the mapstart */
498 if (src->curoffset >= mapstart) {
499 /* if the end is before the mapend, the buffer is in current mmap region... */
500 /* ('cause by definition if readend is in the buffer, so's readstart) */
501 if (readend <= mapend) {
502 fs_print ("read buf %llu+%d lives in current mapbuf %lld+%d, creating subbuffer of mapbuf\n",
503 src->curoffset, readsize, mapstart, GST_BUFFER_SIZE(src->mapbuf));
504 buf = gst_buffer_create_sub (src->mapbuf, src->curoffset - GST_BUFFER_OFFSET(src->mapbuf),
507 /* if the start actually is within the current mmap region, map an overlap buffer */
508 } else if (src->curoffset < mapend) {
509 fs_print ("read buf %llu+%d starts in mapbuf %d+%d but ends outside, creating new mmap\n",
510 src->curoffset,readsize,GST_BUFFER_OFFSET(src->mapbuf),GST_BUFFER_SIZE(src->mapbuf));
511 buf = gst_filesrc_map_small_region (src, src->curoffset, readsize);
514 /* the only other option is that buffer is totally outside, which means we search for it */
516 /* now we can assume that the start is *before* the current mmap region */
517 /* if the readend is past mapstart, we have two options */
518 } else if (readend >= mapstart) {
519 /* either the read buffer overlaps the start of the mmap region */
520 /* or the read buffer fully contains the current mmap region */
521 /* either way, it's really not relevant, we just create a new region anyway*/
522 fs_print ("read buf %llu+%d starts before mapbuf %d+%d, but overlaps it\n",
523 src->curoffset,readsize,GST_BUFFER_OFFSET(src->mapbuf),GST_BUFFER_SIZE(src->mapbuf));
524 buf = gst_filesrc_map_small_region (src, src->curoffset, readsize);
527 /* then deal with the case where the read buffer is totally outside */
529 /* first check to see if there's a map that covers the right region already */
530 fs_print ("searching for mapbuf to cover %llu+%d\n",src->curoffset,readsize);
531 region.offset = src->curoffset;
532 region.size = readsize;
533 map = g_tree_search (src->map_regions,
534 (GCompareFunc) gst_filesrc_search_region_match,
537 /* if we found an exact match, subbuffer it */
539 fs_print ("found mapbuf at %d+%d, creating subbuffer\n",GST_BUFFER_OFFSET(map),GST_BUFFER_SIZE(map));
540 buf = gst_buffer_create_sub (map, src->curoffset - GST_BUFFER_OFFSET(map), readsize);
542 /* otherwise we need to create something out of thin air */
544 /* if the read buffer crosses a mmap region boundary, create a one-off region */
545 if ((src->curoffset / src->mapsize) != (readend / src->mapsize)) {
546 fs_print ("read buf %llu+%d crosses a %d-byte boundary, creating a one-off\n",
547 src->curoffset,readsize,src->mapsize);
548 buf = gst_filesrc_map_small_region (src, src->curoffset, readsize);
550 /* otherwise we will create a new mmap region and set it to the default */
554 off_t nextmap = src->curoffset - (src->curoffset % src->mapsize);
555 fs_print ("read buf %llu+%d in new mapbuf at %llu+%d, mapping and subbuffering\n",
556 src->curoffset, readsize, nextmap, src->mapsize);
557 /* first, we're done with the old mapbuf */
558 gst_buffer_unref(src->mapbuf);
559 mapsize = src->mapsize;
561 /* double the mapsize as long as the readsize is smaller */
562 while (readsize - (src->curoffset - nextmap) > mapsize) {
563 fs_print ("readsize smaller then mapsize %08x %d\n", readsize, mapsize);
566 /* create a new one */
567 src->mapbuf = gst_filesrc_map_region (src, nextmap, mapsize);
569 buf = gst_buffer_create_sub (src->mapbuf, src->curoffset - nextmap, readsize);
574 /* if we need to touch the buffer (to bring it into memory), do so */
576 volatile guchar *p = GST_BUFFER_DATA (buf), c;
577 for (i=0;i<GST_BUFFER_SIZE(buf);i+=src->pagesize)
581 /* we're done, return the buffer */
582 src->curoffset += GST_BUFFER_SIZE(buf);
586 /* open the file and mmap it, necessary to go to READY state */
588 gst_filesrc_open_file (GstFileSrc *src)
590 g_return_val_if_fail (!GST_FLAG_IS_SET (src ,GST_FILESRC_OPEN), FALSE);
592 GST_DEBUG(0, "opening file %s",src->filename);
595 src->fd = open (src->filename, O_RDONLY);
597 gst_element_error (GST_ELEMENT (src), "opening file \"%s\" (%s)",
598 src->filename, strerror (errno), NULL);
601 /* check if it is a regular file, otherwise bail out */
602 struct stat stat_results;
604 fstat(src->fd, &stat_results);
606 if (!S_ISREG(stat_results.st_mode)) {
607 gst_element_error (GST_ELEMENT (src), "opening file \"%s\" failed. it isn't a regular file",
608 src->filename, NULL);
613 /* find the file length */
614 src->filelen = lseek (src->fd, 0, SEEK_END);
615 lseek (src->fd, 0, SEEK_SET);
617 /* allocate the first mmap'd region */
618 src->mapbuf = gst_filesrc_map_region (src, 0, src->mapsize);
622 GST_FLAG_SET (src, GST_FILESRC_OPEN);
627 /* unmap and close the file */
629 gst_filesrc_close_file (GstFileSrc *src)
631 g_return_if_fail (GST_FLAG_IS_SET (src, GST_FILESRC_OPEN));
636 /* zero out a lot of our state */
642 gst_buffer_unref (src->mapbuf);
644 GST_FLAG_UNSET (src, GST_FILESRC_OPEN);
648 static GstElementStateReturn
649 gst_filesrc_change_state (GstElement *element)
651 GstFileSrc *src = GST_FILESRC(element);
653 switch (GST_STATE_TRANSITION (element)) {
654 case GST_STATE_NULL_TO_READY:
656 case GST_STATE_READY_TO_NULL:
658 case GST_STATE_READY_TO_PAUSED:
659 if (!GST_FLAG_IS_SET (element, GST_FILESRC_OPEN)) {
660 if (!gst_filesrc_open_file (GST_FILESRC (element)))
661 return GST_STATE_FAILURE;
664 case GST_STATE_PAUSED_TO_READY:
665 if (GST_FLAG_IS_SET (element, GST_FILESRC_OPEN))
666 gst_filesrc_close_file (GST_FILESRC (element));
667 src->seek_happened = TRUE;
673 if (GST_ELEMENT_CLASS (parent_class)->change_state)
674 return GST_ELEMENT_CLASS (parent_class)->change_state (element);
676 return GST_STATE_SUCCESS;
680 gst_filesrc_srcpad_query (GstPad *pad, GstPadQueryType type,
681 GstFormat *format, gint64 *value)
683 GstFileSrc *src = GST_FILESRC (GST_PAD_PARENT (pad));
686 case GST_PAD_QUERY_TOTAL:
687 if (*format != GST_FORMAT_BYTES) {
690 *value = src->filelen;
692 case GST_PAD_QUERY_POSITION:
693 if (*format != GST_FORMAT_BYTES) {
696 *value = src->curoffset;
706 gst_filesrc_srcpad_event (GstPad *pad, GstEvent *event)
708 GstFileSrc *src = GST_FILESRC (GST_PAD_PARENT (pad));
710 GST_DEBUG(0, "event %d", GST_EVENT_TYPE (event));
712 switch (GST_EVENT_TYPE (event)) {
717 if (GST_EVENT_SEEK_FORMAT (event) != GST_FORMAT_BYTES) {
721 offset = GST_EVENT_SEEK_OFFSET (event);
723 switch (GST_EVENT_SEEK_METHOD (event)) {
724 case GST_SEEK_METHOD_SET:
725 if (offset > src->filelen)
727 src->curoffset = offset;
728 GST_DEBUG(0, "seek set pending to %lld", src->curoffset);
730 case GST_SEEK_METHOD_CUR:
731 if (offset + src->curoffset > src->filelen)
733 src->curoffset += offset;
734 GST_DEBUG(0, "seek cur pending to %lld", src->curoffset);
736 case GST_SEEK_METHOD_END:
737 if (ABS (offset) > src->filelen)
739 src->curoffset = src->filelen - ABS (offset);
740 GST_DEBUG(0, "seek end pending to %lld", src->curoffset);
746 src->seek_happened = TRUE;
747 src->need_flush = GST_EVENT_SEEK_FLAGS(event) & GST_SEEK_FLAG_FLUSH;
751 if (GST_EVENT_SIZE_FORMAT (event) != GST_FORMAT_BYTES) {
754 src->block_size = GST_EVENT_SIZE_VALUE (event);
755 g_object_notify (G_OBJECT (src), "blocksize");
757 case GST_EVENT_FLUSH:
758 src->need_flush = TRUE;
764 gst_event_unref (event);
768 gst_event_unref (event);