2 * (c) 2003 Ronald Bultje <rbultje@ronald.bitfreak.net>
3 * (c) 2005 Michal Benes <michal.benes@xeris.cz>
5 * ebml-write.c: write EBML data to file/stream
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.
29 #include "ebml-write.h"
33 GST_DEBUG_CATEGORY_STATIC (gst_ebml_write_debug);
34 #define GST_CAT_DEFAULT gst_ebml_write_debug
36 #define _do_init(thing) \
37 GST_DEBUG_CATEGORY_INIT (gst_ebml_write_debug, "ebmlwrite", 0, "Write EBML structured data")
38 GST_BOILERPLATE_FULL (GstEbmlWrite, gst_ebml_write, GstObject, GST_TYPE_OBJECT,
41 static void gst_ebml_write_finalize (GObject * object);
44 gst_ebml_write_base_init (gpointer g_class)
49 gst_ebml_write_class_init (GstEbmlWriteClass * klass)
51 GObjectClass *object = G_OBJECT_CLASS (klass);
53 object->finalize = gst_ebml_write_finalize;
57 gst_ebml_write_init (GstEbmlWrite * ebml, GstEbmlWriteClass * klass)
61 ebml->last_pos = G_MAXUINT64; /* force newsegment event */
64 ebml->streamheader = NULL;
65 ebml->streamheader_pos = 0;
66 ebml->writing_streamheader = FALSE;
71 gst_ebml_write_finalize (GObject * object)
73 GstEbmlWrite *ebml = GST_EBML_WRITE (object);
75 gst_object_unref (ebml->srcpad);
78 gst_byte_writer_free (ebml->cache);
82 if (ebml->streamheader) {
83 gst_byte_writer_free (ebml->streamheader);
84 ebml->streamheader = NULL;
88 gst_caps_unref (ebml->caps);
92 GST_CALL_PARENT (G_OBJECT_CLASS, finalize, (object));
98 * @srcpad: Source pad to which the output will be pushed.
100 * Creates a new #GstEbmlWrite.
102 * Returns: a new #GstEbmlWrite
105 gst_ebml_write_new (GstPad * srcpad)
108 GST_EBML_WRITE (g_object_new (GST_TYPE_EBML_WRITE, NULL));
110 ebml->srcpad = gst_object_ref (srcpad);
111 ebml->timestamp = GST_CLOCK_TIME_NONE;
113 gst_ebml_write_reset (ebml);
120 * gst_ebml_write_reset:
121 * @ebml: a #GstEbmlWrite.
123 * Reset internal state of #GstEbmlWrite.
126 gst_ebml_write_reset (GstEbmlWrite * ebml)
129 ebml->last_pos = G_MAXUINT64; /* force newsegment event */
132 gst_byte_writer_free (ebml->cache);
137 gst_caps_unref (ebml->caps);
141 ebml->last_write_result = GST_FLOW_OK;
142 ebml->timestamp = GST_CLOCK_TIME_NONE;
147 * gst_ebml_last_write_result:
148 * @ebml: a #GstEbmlWrite.
150 * Returns: GST_FLOW_OK if there was not write error since the last call of
151 * gst_ebml_last_write_result or code of the error.
154 gst_ebml_last_write_result (GstEbmlWrite * ebml)
156 GstFlowReturn res = ebml->last_write_result;
158 ebml->last_write_result = GST_FLOW_OK;
165 gst_ebml_start_streamheader (GstEbmlWrite * ebml)
167 g_return_if_fail (ebml->streamheader == NULL);
169 GST_DEBUG ("Starting streamheader at %" G_GUINT64_FORMAT, ebml->pos);
170 ebml->streamheader = gst_byte_writer_new_with_size (1000, FALSE);
171 ebml->streamheader_pos = ebml->pos;
172 ebml->writing_streamheader = TRUE;
176 gst_ebml_stop_streamheader (GstEbmlWrite * ebml)
180 if (!ebml->streamheader)
183 buffer = gst_byte_writer_free_and_get_buffer (ebml->streamheader);
184 ebml->streamheader = NULL;
185 GST_DEBUG ("Streamheader was size %d", GST_BUFFER_SIZE (buffer));
187 ebml->writing_streamheader = FALSE;
192 * gst_ebml_write_set_cache:
193 * @ebml: a #GstEbmlWrite.
194 * @size: size of the cache.
197 * The idea is that you use this for writing a lot
198 * of small elements. This will just "queue" all of
199 * them and they'll be pushed to the next element all
200 * at once. This saves memory and time for buffer
201 * allocation and init, and it looks better.
204 gst_ebml_write_set_cache (GstEbmlWrite * ebml, guint size)
206 g_return_if_fail (ebml->cache == NULL);
208 GST_DEBUG ("Starting cache at %" G_GUINT64_FORMAT, ebml->pos);
209 ebml->cache = gst_byte_writer_new_with_size (size, FALSE);
210 ebml->cache_pos = ebml->pos;
214 gst_ebml_writer_send_new_segment_event (GstEbmlWrite * ebml, guint64 new_pos)
218 GST_INFO ("seeking to %" G_GUINT64_FORMAT, new_pos);
220 res = gst_pad_push_event (ebml->srcpad,
221 gst_event_new_new_segment (FALSE, 1.0, GST_FORMAT_BYTES, new_pos, -1, 0));
224 GST_WARNING ("seek to %" G_GUINT64_FORMAT "failed", new_pos);
230 * gst_ebml_write_flush_cache:
231 * @ebml: a #GstEbmlWrite.
232 * @timestamp: timestamp of the buffer.
237 gst_ebml_write_flush_cache (GstEbmlWrite * ebml, gboolean is_keyframe,
238 GstClockTime timestamp)
245 buffer = gst_byte_writer_free_and_get_buffer (ebml->cache);
247 GST_DEBUG ("Flushing cache of size %d", GST_BUFFER_SIZE (buffer));
248 gst_buffer_set_caps (buffer, ebml->caps);
249 GST_BUFFER_TIMESTAMP (buffer) = timestamp;
250 GST_BUFFER_OFFSET (buffer) = ebml->pos - GST_BUFFER_SIZE (buffer);
251 GST_BUFFER_OFFSET_END (buffer) = ebml->pos;
252 if (ebml->last_write_result == GST_FLOW_OK) {
253 if (GST_BUFFER_OFFSET (buffer) != ebml->last_pos) {
254 gst_ebml_writer_send_new_segment_event (ebml, GST_BUFFER_OFFSET (buffer));
255 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_DISCONT);
257 if (ebml->writing_streamheader) {
258 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_IN_CAPS);
261 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_DELTA_UNIT);
263 ebml->last_pos = ebml->pos;
264 ebml->last_write_result = gst_pad_push (ebml->srcpad, buffer);
266 gst_buffer_unref (buffer);
272 * gst_ebml_write_element_new:
273 * @ebml: a #GstEbmlWrite.
274 * @size: size of the requested buffer.
276 * Create a buffer for one element. If there is
277 * a cache, use that instead.
279 * Returns: A new #GstBuffer.
282 gst_ebml_write_element_new (GstEbmlWrite * ebml, guint8 ** data_out, guint size)
284 /* Create new buffer of size + ID + length */
290 buf = gst_buffer_new_and_alloc (size);
291 GST_BUFFER_TIMESTAMP (buf) = ebml->timestamp;
293 *data_out = GST_BUFFER_DATA (buf);
300 * gst_ebml_write_element_id:
301 * @data_inout: Pointer to data pointer
302 * @id: Element ID that should be written.
304 * Write element ID into a buffer.
307 gst_ebml_write_element_id (guint8 ** data_inout, guint32 id)
309 guint8 *data = *data_inout;
310 guint bytes = 4, mask = 0x10;
313 while (!(id & (mask << ((bytes - 1) * 8))) && bytes > 0) {
318 /* if invalid ID, use dummy */
320 GST_WARNING ("Invalid ID, voiding");
322 id = GST_EBML_ID_VOID;
326 *data_inout += bytes;
328 data[bytes] = id & 0xff;
335 * gst_ebml_write_element_size:
336 * @data_inout: Pointer to data pointer
337 * @size: Element length.
339 * Write element length into a buffer.
342 gst_ebml_write_element_size (guint8 ** data_inout, guint64 size)
344 guint8 *data = *data_inout;
345 guint bytes = 1, mask = 0x80;
347 if (size != GST_EBML_SIZE_UNKNOWN) {
348 /* how many bytes? - use mask-1 because an all-1 bitset is not allowed */
349 while ((size >> ((bytes - 1) * 8)) >= (mask - 1) && bytes <= 8) {
354 /* if invalid size, use max. */
356 GST_WARNING ("Invalid size, writing size unknown");
359 /* Now here's a real FIXME: we cannot read those yet! */
360 size = GST_EBML_SIZE_UNKNOWN;
367 /* write out, BE, with length size marker */
368 *data_inout += bytes;
369 while (bytes-- > 0) {
370 data[bytes] = size & 0xff;
379 * gst_ebml_write_element_data:
380 * @data_inout: Pointer to data pointer
381 * @write: Data that should be written.
382 * @length: Length of the data.
384 * Write element data into a buffer.
387 gst_ebml_write_element_data (guint8 ** data_inout, guint8 * write,
390 memcpy (*data_inout, write, length);
391 *data_inout += length;
396 * gst_ebml_write_element_push:
397 * @ebml: #GstEbmlWrite
398 * @buf: #GstBuffer to be written.
399 * @buf_data: Start of data to push from @buf (or NULL for whole buffer).
400 * @buf_data_end: Data pointer positioned after the last byte in @buf_data (or
401 * NULL for whole buffer).
403 * Write out buffer by moving it to the next element.
406 gst_ebml_write_element_push (GstEbmlWrite * ebml, GstBuffer * buf,
407 guint8 * buf_data, guint8 * buf_data_end)
412 buf_data = GST_BUFFER_DATA (buf);
415 data_size = buf_data_end - buf_data;
417 data_size = GST_BUFFER_SIZE (buf);
419 ebml->pos += data_size;
421 /* if there's no cache, then don't push it! */
422 if (ebml->writing_streamheader) {
423 gst_byte_writer_put_data (ebml->streamheader, buf_data, data_size);
426 gst_byte_writer_put_data (ebml->cache, buf_data, data_size);
427 gst_buffer_unref (buf);
431 if (ebml->last_write_result == GST_FLOW_OK) {
432 buf = gst_buffer_make_metadata_writable (buf);
433 gst_buffer_set_caps (buf, ebml->caps);
434 GST_BUFFER_OFFSET (buf) = ebml->pos - data_size;
435 GST_BUFFER_OFFSET_END (buf) = ebml->pos;
436 if (ebml->writing_streamheader) {
437 GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_IN_CAPS);
439 GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_DELTA_UNIT);
441 if (GST_BUFFER_OFFSET (buf) != ebml->last_pos) {
442 gst_ebml_writer_send_new_segment_event (ebml, GST_BUFFER_OFFSET (buf));
443 GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_DISCONT);
445 ebml->last_pos = ebml->pos;
446 ebml->last_write_result = gst_pad_push (ebml->srcpad, buf);
448 gst_buffer_unref (buf);
454 * gst_ebml_write_seek:
455 * @ebml: #GstEbmlWrite
456 * @pos: Seek position.
461 gst_ebml_write_seek (GstEbmlWrite * ebml, guint64 pos)
463 if (ebml->writing_streamheader) {
464 GST_DEBUG ("wanting to seek to pos %" G_GUINT64_FORMAT, pos);
465 if (pos >= ebml->streamheader_pos &&
466 pos <= ebml->streamheader_pos + ebml->streamheader->parent.size) {
467 gst_byte_writer_set_pos (ebml->streamheader,
468 pos - ebml->streamheader_pos);
469 GST_DEBUG ("seeked in streamheader to position %" G_GUINT64_FORMAT,
470 pos - ebml->streamheader_pos);
473 ("we are writing streamheader still and seek is out of bounds");
476 /* Cache seeking. A bit dangerous, we assume the client writer
477 * knows what he's doing... */
480 if (pos >= ebml->cache_pos &&
481 pos <= ebml->cache_pos + ebml->cache->parent.size) {
482 GST_DEBUG ("seeking in cache to %" G_GUINT64_FORMAT, pos);
484 gst_byte_writer_set_pos (ebml->cache, ebml->pos - ebml->cache_pos);
487 GST_LOG ("Seek outside cache range. Clearing...");
488 gst_ebml_write_flush_cache (ebml, FALSE, GST_CLOCK_TIME_NONE);
492 GST_INFO ("scheduling seek to %" G_GUINT64_FORMAT, pos);
498 * gst_ebml_write_get_uint_size:
499 * @num: Number to be encoded.
501 * Get number of bytes needed to write a uint.
503 * Returns: Encoded uint length.
506 gst_ebml_write_get_uint_size (guint64 num)
511 while (num >= (G_GINT64_CONSTANT (1) << (size * 8)) && size < 8) {
520 * gst_ebml_write_set_uint:
521 * @data_inout: Pointer to data pointer
522 * @num: Number to be written.
523 * @size: Encoded number length.
525 * Write an uint into a buffer.
528 gst_ebml_write_set_uint (guint8 ** data_inout, guint64 num, guint size)
530 guint8 *data = *data_inout;
535 data[size] = num & 0xff;
542 * gst_ebml_write_uint:
543 * @ebml: #GstEbmlWrite
545 * @num: Number to be written.
547 * Write uint element.
550 gst_ebml_write_uint (GstEbmlWrite * ebml, guint32 id, guint64 num)
553 guint8 *data_start, *data_end;
554 guint size = gst_ebml_write_get_uint_size (num);
556 buf = gst_ebml_write_element_new (ebml, &data_start, sizeof (num));
557 data_end = data_start;
560 gst_ebml_write_element_id (&data_end, id);
561 gst_ebml_write_element_size (&data_end, size);
562 gst_ebml_write_set_uint (&data_end, num, size);
563 gst_ebml_write_element_push (ebml, buf, data_start, data_end);
568 * gst_ebml_write_sint:
569 * @ebml: #GstEbmlWrite
571 * @num: Number to be written.
573 * Write sint element.
576 gst_ebml_write_sint (GstEbmlWrite * ebml, guint32 id, gint64 num)
579 guint8 *data_start, *data_end;
580 /* if the signed number is on the edge of a extra-byte,
581 * then we'll fall over when detecting it. Example: if I
582 * have a number (-)0x8000 (G_MINSHORT), then my abs()<<1
583 * will be 0x10000; this is G_MAXUSHORT+1! So: if (<0) -1. */
584 guint64 unum = (num < 0 ? (-num - 1) << 1 : num << 1);
585 guint size = gst_ebml_write_get_uint_size (unum);
587 buf = gst_ebml_write_element_new (ebml, &data_start, sizeof (num));
588 data_end = data_start;
594 unum = 0x80 << (size - 1);
596 unum |= 0x80 << (size - 1);
600 gst_ebml_write_element_id (&data_end, id);
601 gst_ebml_write_element_size (&data_end, size);
602 gst_ebml_write_set_uint (&data_end, unum, size);
603 gst_ebml_write_element_push (ebml, buf, data_start, data_end);
608 * gst_ebml_write_float:
609 * @ebml: #GstEbmlWrite
611 * @num: Number to be written.
613 * Write float element.
616 gst_ebml_write_float (GstEbmlWrite * ebml, guint32 id, gdouble num)
619 guint8 *data_start, *data_end;
621 buf = gst_ebml_write_element_new (ebml, &data_start, sizeof (num));
622 data_end = data_start;
624 gst_ebml_write_element_id (&data_end, id);
625 gst_ebml_write_element_size (&data_end, 8);
626 num = GDOUBLE_TO_BE (num);
627 gst_ebml_write_element_data (&data_end, (guint8 *) & num, 8);
628 gst_ebml_write_element_push (ebml, buf, data_start, data_end);
633 * gst_ebml_write_ascii:
634 * @ebml: #GstEbmlWrite
636 * @str: String to be written.
638 * Write string element.
641 gst_ebml_write_ascii (GstEbmlWrite * ebml, guint32 id, const gchar * str)
643 gint len = strlen (str) + 1; /* add trailing '\0' */
645 guint8 *data_start, *data_end;
647 buf = gst_ebml_write_element_new (ebml, &data_start, len);
648 data_end = data_start;
650 gst_ebml_write_element_id (&data_end, id);
651 gst_ebml_write_element_size (&data_end, len);
652 gst_ebml_write_element_data (&data_end, (guint8 *) str, len);
653 gst_ebml_write_element_push (ebml, buf, data_start, data_end);
658 * gst_ebml_write_utf8:
659 * @ebml: #GstEbmlWrite
661 * @str: String to be written.
663 * Write utf8 encoded string element.
666 gst_ebml_write_utf8 (GstEbmlWrite * ebml, guint32 id, const gchar * str)
668 gst_ebml_write_ascii (ebml, id, str);
673 * gst_ebml_write_date:
674 * @ebml: #GstEbmlWrite
676 * @date: Date in seconds since the unix epoch.
678 * Write date element.
681 gst_ebml_write_date (GstEbmlWrite * ebml, guint32 id, gint64 date)
683 gst_ebml_write_sint (ebml, id, (date - GST_EBML_DATE_OFFSET) * GST_SECOND);
687 * gst_ebml_write_master_start:
688 * @ebml: #GstEbmlWrite
691 * Start wiriting mater element.
693 * Master writing is annoying. We use a size marker of
694 * the max. allowed length, so that we can later fill it
697 * Returns: Master starting position.
700 gst_ebml_write_master_start (GstEbmlWrite * ebml, guint32 id)
702 guint64 pos = ebml->pos;
704 guint8 *data_start, *data_end;
706 buf = gst_ebml_write_element_new (ebml, &data_start, 0);
707 data_end = data_start;
709 gst_ebml_write_element_id (&data_end, id);
710 pos += data_end - data_start;
711 gst_ebml_write_element_size (&data_end, GST_EBML_SIZE_UNKNOWN);
712 gst_ebml_write_element_push (ebml, buf, data_start, data_end);
719 * gst_ebml_write_master_finish_full:
720 * @ebml: #GstEbmlWrite
721 * @startpos: Master starting position.
723 * Finish writing master element. Size of master element is difference between
724 * current position and the element start, and @extra_size added to this.
727 gst_ebml_write_master_finish_full (GstEbmlWrite * ebml, guint64 startpos,
730 guint64 pos = ebml->pos;
733 gst_ebml_write_seek (ebml, startpos);
735 buf = gst_buffer_new_and_alloc (8);
736 GST_WRITE_UINT64_BE (GST_BUFFER_DATA (buf),
737 (G_GINT64_CONSTANT (1) << 56) | (pos - startpos - 8 + extra_size));
739 gst_ebml_write_element_push (ebml, buf, NULL, NULL);
740 gst_ebml_write_seek (ebml, pos);
744 gst_ebml_write_master_finish (GstEbmlWrite * ebml, guint64 startpos)
746 gst_ebml_write_master_finish_full (ebml, startpos, 0);
750 * gst_ebml_write_binary:
751 * @ebml: #GstEbmlWrite
753 * @binary: Data to be written.
754 * @length: Length of the data
756 * Write an element with binary data.
759 gst_ebml_write_binary (GstEbmlWrite * ebml,
760 guint32 id, guint8 * binary, guint64 length)
763 guint8 *data_start, *data_end;
765 buf = gst_ebml_write_element_new (ebml, &data_start, length);
766 data_end = data_start;
768 gst_ebml_write_element_id (&data_end, id);
769 gst_ebml_write_element_size (&data_end, length);
770 gst_ebml_write_element_data (&data_end, binary, length);
771 gst_ebml_write_element_push (ebml, buf, data_start, data_end);
776 * gst_ebml_write_buffer_header:
777 * @ebml: #GstEbmlWrite
779 * @length: Length of the data
781 * Write header of the binary element (use with gst_ebml_write_buffer function).
783 * For things like video frames and audio samples,
784 * you want to use this function, as it doesn't have
785 * the overhead of memcpy() that other functions
786 * such as write_binary() do have.
789 gst_ebml_write_buffer_header (GstEbmlWrite * ebml, guint32 id, guint64 length)
792 guint8 *data_start, *data_end;
794 buf = gst_ebml_write_element_new (ebml, &data_start, 0);
795 data_end = data_start;
797 gst_ebml_write_element_id (&data_end, id);
798 gst_ebml_write_element_size (&data_end, length);
799 gst_ebml_write_element_push (ebml, buf, data_start, data_end);
804 * gst_ebml_write_buffer:
805 * @ebml: #GstEbmlWrite
806 * @buf: #GstBuffer cointaining the data.
808 * Write binary element (see gst_ebml_write_buffer_header).
811 gst_ebml_write_buffer (GstEbmlWrite * ebml, GstBuffer * buf)
813 gst_ebml_write_element_push (ebml, buf, NULL, NULL);
818 * gst_ebml_replace_uint:
819 * @ebml: #GstEbmlWrite
820 * @pos: Position of the uint that should be replaced.
823 * Replace uint with a new value.
825 * When replacing a uint, we assume that it is *always*
826 * 8-byte, since that's the safest guess we can do. This
827 * is just for simplicity.
829 * FIXME: this function needs to be replaced with something
830 * proper. This is a crude hack.
833 gst_ebml_replace_uint (GstEbmlWrite * ebml, guint64 pos, guint64 num)
835 guint64 oldpos = ebml->pos;
836 GstBuffer *buf = gst_buffer_new_and_alloc (8);
837 guint8 *data_start, *data_end;
839 data_start = GST_BUFFER_DATA (buf);
840 data_end = data_start;
842 gst_ebml_write_seek (ebml, pos);
843 gst_ebml_write_set_uint (&data_end, num, 8);
845 gst_ebml_write_element_push (ebml, buf, data_start, data_end);
846 gst_ebml_write_seek (ebml, oldpos);
850 * gst_ebml_write_header:
851 * @ebml: #GstEbmlWrite
852 * @doctype: Document type.
853 * @version: Document type version.
858 gst_ebml_write_header (GstEbmlWrite * ebml, const gchar * doctype,
863 /* write the basic EBML header */
864 gst_ebml_write_set_cache (ebml, 0x40);
865 pos = gst_ebml_write_master_start (ebml, GST_EBML_ID_HEADER);
866 #if (GST_EBML_VERSION != 1)
867 gst_ebml_write_uint (ebml, GST_EBML_ID_EBMLVERSION, GST_EBML_VERSION);
868 gst_ebml_write_uint (ebml, GST_EBML_ID_EBMLREADVERSION, GST_EBML_VERSION);
871 /* we don't write these until they're "non-default" (never!) */
872 gst_ebml_write_uint (ebml, GST_EBML_ID_EBMLMAXIDLENGTH, sizeof (guint32));
873 gst_ebml_write_uint (ebml, GST_EBML_ID_EBMLMAXSIZELENGTH, sizeof (guint64));
875 gst_ebml_write_ascii (ebml, GST_EBML_ID_DOCTYPE, doctype);
876 gst_ebml_write_uint (ebml, GST_EBML_ID_DOCTYPEVERSION, version);
877 gst_ebml_write_uint (ebml, GST_EBML_ID_DOCTYPEREADVERSION, version);
878 gst_ebml_write_master_finish (ebml, pos);
879 gst_ebml_write_flush_cache (ebml, FALSE, 0);