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 = {
75 "Read from arbitrary point in a file",
77 "Erik Walthinsen <omega@cse.ogi.edu>",
81 /*#define fs_print(format,args...) g_print(format, ## args) */
82 #define fs_print(format,args...)
84 /* FileSrc signals and args */
102 static void gst_filesrc_class_init (GstFileSrcClass *klass);
103 static void gst_filesrc_init (GstFileSrc *filesrc);
104 static void gst_filesrc_dispose (GObject *object);
106 static void gst_filesrc_set_property (GObject *object, guint prop_id,
107 const GValue *value, GParamSpec *pspec);
108 static void gst_filesrc_get_property (GObject *object, guint prop_id,
109 GValue *value, GParamSpec *pspec);
111 static GstBuffer * gst_filesrc_get (GstPad *pad);
112 static gboolean gst_filesrc_srcpad_event (GstPad *pad, GstEvent *event);
113 static gboolean gst_filesrc_srcpad_query (GstPad *pad, GstPadQueryType type,
114 GstSeekType *format, gint64 *value);
116 static GstElementStateReturn gst_filesrc_change_state (GstElement *element);
119 static GstElementClass *parent_class = NULL;
120 /*static guint gst_filesrc_signals[LAST_SIGNAL] = { 0 };*/
123 gst_filesrc_get_type(void)
125 static GType filesrc_type = 0;
128 static const GTypeInfo filesrc_info = {
129 sizeof(GstFileSrcClass), NULL,
131 (GClassInitFunc)gst_filesrc_class_init,
136 (GInstanceInitFunc)gst_filesrc_init,
138 filesrc_type = g_type_register_static (GST_TYPE_ELEMENT, "GstFileSrc", &filesrc_info, 0);
144 gst_filesrc_class_init (GstFileSrcClass *klass)
146 GObjectClass *gobject_class;
147 GstElementClass *gstelement_class;
149 gobject_class = (GObjectClass*)klass;
150 gstelement_class = (GstElementClass*)klass;
152 parent_class = g_type_class_ref (GST_TYPE_ELEMENT);
154 gst_element_class_install_std_props (
155 GST_ELEMENT_CLASS (klass),
156 "fd", ARG_FD, G_PARAM_READABLE,
157 "offset", ARG_OFFSET, G_PARAM_READWRITE,
158 "filesize", ARG_FILESIZE, G_PARAM_READABLE,
159 "location", ARG_LOCATION, G_PARAM_READWRITE,
160 "blocksize", ARG_BLOCKSIZE, G_PARAM_READWRITE,
161 "mmapsize", ARG_MAPSIZE, G_PARAM_READWRITE,
162 "touch", ARG_TOUCH, G_PARAM_READWRITE,
165 gobject_class->dispose = gst_filesrc_dispose;
166 gobject_class->set_property = gst_filesrc_set_property;
167 gobject_class->get_property = gst_filesrc_get_property;
169 gstelement_class->change_state = gst_filesrc_change_state;
173 gst_filesrc_bufcmp (gconstpointer a, gconstpointer b)
175 /* GstBuffer *bufa = (GstBuffer *)a, *bufb = (GstBuffer *)b;*/
177 /* sort first by offset, then in reverse by size */
178 if (GST_BUFFER_OFFSET(a) < GST_BUFFER_OFFSET(b)) return -1;
179 else if (GST_BUFFER_OFFSET(a) > GST_BUFFER_OFFSET(b)) return 1;
180 else if (GST_BUFFER_SIZE(a) > GST_BUFFER_SIZE(b)) return -1;
181 else if (GST_BUFFER_SIZE(a) < GST_BUFFER_SIZE(b)) return 1;
186 gst_filesrc_init (GstFileSrc *src)
188 src->srcpad = gst_pad_new ("src", GST_PAD_SRC);
189 gst_pad_set_get_function (src->srcpad, gst_filesrc_get);
190 gst_pad_set_event_function (src->srcpad, gst_filesrc_srcpad_event);
191 gst_pad_set_query_function (src->srcpad, gst_filesrc_srcpad_query);
192 gst_element_add_pad (GST_ELEMENT (src), src->srcpad);
194 src->pagesize = getpagesize();
196 src->filename = NULL;
201 src->block_size = 4096;
205 src->mapsize = 4 * 1024 * 1024; /* default is 4MB */
207 src->map_regions = g_tree_new (gst_filesrc_bufcmp);
208 src->map_regions_lock = g_mutex_new();
210 src->seek_happened = FALSE;
214 gst_filesrc_dispose (GObject *object)
218 src = GST_FILESRC (object);
220 G_OBJECT_CLASS (parent_class)->dispose (object);
222 g_tree_destroy (src->map_regions);
223 g_mutex_free (src->map_regions_lock);
225 g_free (src->filename);
230 gst_filesrc_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
234 /* it's not null if we got it, but it might not be ours */
235 g_return_if_fail (GST_IS_FILESRC (object));
237 src = GST_FILESRC (object);
241 /* the element must be stopped in order to do this */
242 g_return_if_fail (GST_STATE (src) < GST_STATE_PLAYING);
244 if (src->filename) g_free (src->filename);
245 /* clear the filename if we get a NULL (is that possible?) */
246 if (g_value_get_string (value) == NULL) {
247 gst_element_set_state (GST_ELEMENT (object), GST_STATE_NULL);
248 src->filename = NULL;
249 /* otherwise set the new filename */
251 src->filename = g_strdup (g_value_get_string (value));
253 g_object_notify (G_OBJECT (src), "location");
256 src->block_size = g_value_get_ulong (value);
257 g_object_notify (G_OBJECT (src), "blocksize");
260 src->curoffset = g_value_get_int64 (value);
261 g_object_notify (G_OBJECT (src), "offset");
264 if ((src->mapsize % src->pagesize) == 0) {
265 src->mapsize = g_value_get_ulong (value);
266 g_object_notify (G_OBJECT (src), "mmapsize");
268 GST_INFO(0, "invalid mapsize, must a multiple of pagesize, which is %d\n",src->pagesize);
272 src->touch = g_value_get_boolean (value);
273 g_object_notify (G_OBJECT (src), "touch");
281 gst_filesrc_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
285 /* it's not null if we got it, but it might not be ours */
286 g_return_if_fail (GST_IS_FILESRC (object));
288 src = GST_FILESRC (object);
292 g_value_set_string (value, src->filename);
295 g_value_set_int64 (value, src->filelen);
298 g_value_set_int (value, src->fd);
301 g_value_set_ulong (value, src->block_size);
304 g_value_set_int64 (value, src->curoffset);
307 g_value_set_ulong (value, src->mapsize);
310 g_value_set_boolean (value, src->touch);
313 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
319 gst_filesrc_free_parent_mmap (GstBuffer *buf)
321 GstFileSrc *src = GST_FILESRC(GST_BUFFER_POOL_PRIVATE(buf));
323 fs_print ("freeing mmap()d buffer at %d+%d\n",GST_BUFFER_OFFSET(buf),GST_BUFFER_SIZE(buf));
325 /* remove the buffer from the list of available mmap'd regions */
326 g_mutex_lock(src->map_regions_lock);
327 g_tree_remove(src->map_regions,buf);
328 /* check to see if the tree is empty */
329 if (g_tree_nnodes(src->map_regions) == 0) {
330 /* we have to free the bufferpool we don't have yet */
332 g_mutex_unlock(src->map_regions_lock);
335 /* madvise to tell the kernel what to do with it */
336 madvise(GST_BUFFER_DATA(buf),GST_BUFFER_SIZE(buf),MADV_DONTNEED);
338 /* now unmap the memory */
339 munmap(GST_BUFFER_DATA(buf),GST_BUFFER_MAXSIZE(buf));
343 gst_filesrc_map_region (GstFileSrc *src, off_t offset, size_t size)
348 g_return_val_if_fail (offset >= 0, NULL);
350 fs_print ("mapping region %08lx+%08lx from file into memory\n",offset,size);
352 /* time to allocate a new mapbuf */
353 buf = gst_buffer_new();
354 /* mmap() the data into this new buffer */
355 GST_BUFFER_DATA(buf) = mmap (NULL, size, PROT_READ, MAP_SHARED, src->fd, offset);
356 if (GST_BUFFER_DATA(buf) == NULL) {
357 gst_element_error (GST_ELEMENT (src), "couldn't map file");
358 } else if (GST_BUFFER_DATA(buf) == MAP_FAILED) {
359 gst_element_error (GST_ELEMENT (src), "mmap (0x%x, %d, 0x%llx) : %s",
360 size, src->fd, offset, strerror (errno));
362 #ifdef MADV_SEQUENTIAL
363 /* madvise to tell the kernel what to do with it */
364 retval = madvise(GST_BUFFER_DATA(buf),GST_BUFFER_SIZE(buf),MADV_SEQUENTIAL);
366 /* fill in the rest of the fields */
367 GST_BUFFER_FLAG_SET(buf, GST_BUFFER_READONLY);
368 GST_BUFFER_FLAG_SET(buf, GST_BUFFER_ORIGINAL);
369 GST_BUFFER_SIZE(buf) = size;
370 GST_BUFFER_MAXSIZE(buf) = size;
371 GST_BUFFER_OFFSET(buf) = offset;
372 GST_BUFFER_TIMESTAMP(buf) = -1LL;
373 GST_BUFFER_POOL_PRIVATE(buf) = src;
374 GST_BUFFER_FREE_FUNC(buf) = gst_filesrc_free_parent_mmap;
376 g_mutex_lock(src->map_regions_lock);
377 g_tree_insert(src->map_regions,buf,buf);
378 g_mutex_unlock(src->map_regions_lock);
384 gst_filesrc_map_small_region (GstFileSrc *src, off_t offset, size_t size)
390 /* printf("attempting to map a small buffer at %d+%d\n",offset,size); */
392 /* if the offset starts at a non-page boundary, we have to special case */
393 if ((mod = offset % src->pagesize)) {
396 mapbase = offset - mod;
397 mapsize = ((size + mod + src->pagesize - 1) / src->pagesize) * src->pagesize;
398 /* printf("not on page boundaries, resizing map to %d+%d\n",mapbase,mapsize);*/
399 map = gst_filesrc_map_region(src, mapbase, mapsize);
400 ret = gst_buffer_create_sub (map, offset - mapbase, size);
402 gst_buffer_unref (map);
407 return gst_filesrc_map_region(src,offset,size);
415 /* This allows us to search for a potential mmap region. */
417 gst_filesrc_search_region_match (gpointer a, gpointer b)
419 GstFileSrcRegion *r = (GstFileSrcRegion *)b;
421 /* trying to walk b down the tree, current node is a */
422 if (r->offset < GST_BUFFER_OFFSET(a)) return -1;
423 else if (r->offset >= (GST_BUFFER_OFFSET(a) + GST_BUFFER_SIZE(a))) return 1;
424 else if ((r->offset + r->size) <= (GST_BUFFER_OFFSET(a) + GST_BUFFER_SIZE(a))) return 0;
431 * @pad: #GstPad to push a buffer from
433 * Push a new buffer from the filesrc at the current offset.
436 gst_filesrc_get (GstPad *pad)
439 GstBuffer *buf = NULL, *map;
441 off_t readend,mapstart,mapend;
442 GstFileSrcRegion region;
445 g_return_val_if_fail (pad != NULL, NULL);
446 src = GST_FILESRC (gst_pad_get_parent (pad));
447 g_return_val_if_fail (GST_FLAG_IS_SET (src, GST_FILESRC_OPEN), NULL);
450 if (src->seek_happened) {
453 src->seek_happened = FALSE;
454 GST_DEBUG (GST_CAT_EVENT, "filesrc sending discont\n");
455 event = gst_event_new_discontinuous (FALSE, GST_FORMAT_BYTES, src->curoffset, NULL);
456 GST_EVENT_DISCONT_NEW_MEDIA (event) = FALSE;
457 src->need_flush = FALSE;
458 return GST_BUFFER (event);
460 /* check for flush */
461 if (src->need_flush) {
462 src->need_flush = FALSE;
463 GST_DEBUG (GST_CAT_EVENT, "filesrc sending flush\n");
464 return GST_BUFFER (gst_event_new_flush ());
468 if (src->curoffset == src->filelen) {
469 GST_DEBUG (0, "filesrc eos %lld %lld\n", src->curoffset, src->filelen);
470 gst_element_set_eos (GST_ELEMENT (src));
471 return GST_BUFFER (gst_event_new (GST_EVENT_EOS));
474 /* calculate end pointers so we don't have to do so repeatedly later */
475 readsize = src->block_size;
476 readend = src->curoffset + src->block_size; /* note this is the byte *after* the read */
477 mapstart = GST_BUFFER_OFFSET(src->mapbuf);
478 mapend = mapstart + GST_BUFFER_SIZE(src->mapbuf); /* note this is the byte *after* the map */
480 /* check to see if we're going to overflow the end of the file */
481 if (readend > src->filelen) {
482 readsize = src->filelen - src->curoffset;
483 readend = src->curoffset;
486 /* if the start is past the mapstart */
487 if (src->curoffset >= mapstart) {
488 /* if the end is before the mapend, the buffer is in current mmap region... */
489 /* ('cause by definition if readend is in the buffer, so's readstart) */
490 if (readend <= mapend) {
491 fs_print ("read buf %d+%d lives in current mapbuf %d+%d, creating subbuffer of mapbuf\n",
492 src->curoffset,readsize,GST_BUFFER_OFFSET(src->mapbuf),GST_BUFFER_SIZE(src->mapbuf));
493 buf = gst_buffer_create_sub (src->mapbuf, src->curoffset - GST_BUFFER_OFFSET(src->mapbuf),
496 /* if the start actually is within the current mmap region, map an overlap buffer */
497 } else if (src->curoffset < mapend) {
498 fs_print ("read buf %d+%d starts in mapbuf %d+%d but ends outside, creating new mmap\n",
499 src->curoffset,readsize,GST_BUFFER_OFFSET(src->mapbuf),GST_BUFFER_SIZE(src->mapbuf));
500 buf = gst_filesrc_map_small_region (src, src->curoffset, readsize);
503 /* the only other option is that buffer is totally outside, which means we search for it */
505 /* now we can assume that the start is *before* the current mmap region */
506 /* if the readend is past mapstart, we have two options */
507 } else if (readend >= mapstart) {
508 /* either the read buffer overlaps the start of the mmap region */
509 /* or the read buffer fully contains the current mmap region */
510 /* either way, it's really not relevant, we just create a new region anyway*/
511 fs_print ("read buf %d+%d starts before mapbuf %d+%d, but overlaps it\n",
512 src->curoffset,readsize,GST_BUFFER_OFFSET(src->mapbuf),GST_BUFFER_SIZE(src->mapbuf));
513 buf = gst_filesrc_map_small_region (src, src->curoffset, readsize);
516 /* then deal with the case where the read buffer is totally outside */
518 /* first check to see if there's a map that covers the right region already */
519 fs_print ("searching for mapbuf to cover %d+%d\n",src->curoffset,readsize);
520 region.offset = src->curoffset;
521 region.size = readsize;
522 map = g_tree_search (src->map_regions,
523 (GCompareFunc) gst_filesrc_search_region_match,
526 /* if we found an exact match, subbuffer it */
528 fs_print ("found mapbuf at %d+%d, creating subbuffer\n",GST_BUFFER_OFFSET(map),GST_BUFFER_SIZE(map));
529 buf = gst_buffer_create_sub (map, src->curoffset - GST_BUFFER_OFFSET(map), readsize);
531 /* otherwise we need to create something out of thin air */
533 /* if the read buffer crosses a mmap region boundary, create a one-off region */
534 if ((src->curoffset / src->mapsize) != (readend / src->mapsize)) {
535 fs_print ("read buf %d+%d crosses a %d-byte boundary, creating a one-off\n",
536 src->curoffset,readsize,src->mapsize);
537 buf = gst_filesrc_map_small_region (src, src->curoffset, readsize);
539 /* otherwise we will create a new mmap region and set it to the default */
541 off_t nextmap = src->curoffset - (src->curoffset % src->mapsize);
542 fs_print ("read buf %d+%d in new mapbuf at %d+%d, mapping and subbuffering\n",
543 src->curoffset,readsize,nextmap,src->mapsize);
544 /* first, we're done with the old mapbuf */
545 gst_buffer_unref(src->mapbuf);
546 /* create a new one */
547 src->mapbuf = gst_filesrc_map_region (src, nextmap, src->mapsize);
549 buf = gst_buffer_create_sub (src->mapbuf, src->curoffset - GST_BUFFER_OFFSET(src->mapbuf), readsize);
554 /* if we need to touch the buffer (to bring it into memory), do so */
556 volatile guchar *p = GST_BUFFER_DATA (buf), c;
557 for (i=0;i<GST_BUFFER_SIZE(buf);i+=src->pagesize)
561 /* we're done, return the buffer */
562 src->curoffset += GST_BUFFER_SIZE(buf);
563 g_object_notify (G_OBJECT (src), "offset");
567 /* open the file and mmap it, necessary to go to READY state */
569 gst_filesrc_open_file (GstFileSrc *src)
571 g_return_val_if_fail (!GST_FLAG_IS_SET (src ,GST_FILESRC_OPEN), FALSE);
573 GST_DEBUG(0, "opening file %s",src->filename);
576 src->fd = open (src->filename, O_RDONLY);
578 gst_element_error (GST_ELEMENT (src), "opening file \"%s\" (%s)",
579 src->filename, strerror (errno), NULL);
582 /* check if it is a regular file, otherwise bail out */
583 struct stat stat_results;
585 fstat(src->fd, &stat_results);
587 if (!S_ISREG(stat_results.st_mode)) {
588 gst_element_error (GST_ELEMENT (src), "opening file \"%s\" failed. it isn't a regular file",
589 src->filename, NULL);
594 /* find the file length */
595 src->filelen = lseek (src->fd, 0, SEEK_END);
596 lseek (src->fd, 0, SEEK_SET);
598 /* allocate the first mmap'd region */
599 src->mapbuf = gst_filesrc_map_region (src, 0, src->mapsize);
603 /* now notify of the changes */
604 g_object_freeze_notify (G_OBJECT (src));
605 g_object_notify (G_OBJECT (src), "filesize");
606 g_object_notify (G_OBJECT (src), "offset");
607 g_object_thaw_notify (G_OBJECT (src));
609 GST_FLAG_SET (src, GST_FILESRC_OPEN);
614 /* unmap and close the file */
616 gst_filesrc_close_file (GstFileSrc *src)
618 g_return_if_fail (GST_FLAG_IS_SET (src, GST_FILESRC_OPEN));
623 /* zero out a lot of our state */
627 /* and notify that things changed */
628 g_object_freeze_notify (G_OBJECT (src));
629 g_object_notify (G_OBJECT (src), "filesize");
630 g_object_notify (G_OBJECT (src), "offset");
631 g_object_thaw_notify (G_OBJECT (src));
634 gst_buffer_unref (src->mapbuf);
636 GST_FLAG_UNSET (src, GST_FILESRC_OPEN);
640 static GstElementStateReturn
641 gst_filesrc_change_state (GstElement *element)
643 GstFileSrc *src = GST_FILESRC(element);
645 switch (GST_STATE_TRANSITION (element)) {
646 case GST_STATE_NULL_TO_READY:
648 case GST_STATE_READY_TO_NULL:
650 case GST_STATE_READY_TO_PAUSED:
651 if (!GST_FLAG_IS_SET (element, GST_FILESRC_OPEN)) {
652 if (!gst_filesrc_open_file (GST_FILESRC (element)))
653 return GST_STATE_FAILURE;
656 case GST_STATE_PAUSED_TO_READY:
657 if (GST_FLAG_IS_SET (element, GST_FILESRC_OPEN))
658 gst_filesrc_close_file (GST_FILESRC (element));
659 src->seek_happened = TRUE;
665 if (GST_ELEMENT_CLASS (parent_class)->change_state)
666 return GST_ELEMENT_CLASS (parent_class)->change_state (element);
668 return GST_STATE_SUCCESS;
672 gst_filesrc_srcpad_query (GstPad *pad, GstPadQueryType type,
673 GstFormat *format, gint64 *value)
675 GstFileSrc *src = GST_FILESRC (GST_PAD_PARENT (pad));
678 case GST_PAD_QUERY_TOTAL:
679 if (*format != GST_FORMAT_BYTES) {
682 *value = src->filelen;
684 case GST_PAD_QUERY_POSITION:
685 if (*format != GST_FORMAT_BYTES) {
688 *value = src->curoffset;
698 gst_filesrc_srcpad_event (GstPad *pad, GstEvent *event)
700 GstFileSrc *src = GST_FILESRC (GST_PAD_PARENT (pad));
702 GST_DEBUG(0, "event %d", GST_EVENT_TYPE (event));
704 switch (GST_EVENT_TYPE (event)) {
706 if (GST_EVENT_SEEK_FORMAT (event) != GST_FORMAT_BYTES) {
709 switch (GST_EVENT_SEEK_METHOD (event)) {
710 case GST_SEEK_METHOD_SET:
711 src->curoffset = (guint64) GST_EVENT_SEEK_OFFSET (event);
712 GST_DEBUG(0, "seek set pending to %lld", src->curoffset);
714 case GST_SEEK_METHOD_CUR:
715 src->curoffset += GST_EVENT_SEEK_OFFSET (event);
716 GST_DEBUG(0, "seek cur pending to %lld", src->curoffset);
718 case GST_SEEK_METHOD_END:
719 src->curoffset = src->filelen - ABS (GST_EVENT_SEEK_OFFSET (event));
720 GST_DEBUG(0, "seek end pending to %lld", src->curoffset);
726 g_object_notify (G_OBJECT (src), "offset");
727 src->seek_happened = TRUE;
728 src->need_flush = GST_EVENT_SEEK_FLAGS(event) & GST_SEEK_FLAG_FLUSH;
730 case GST_EVENT_FLUSH:
731 src->need_flush = TRUE;