mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-09-08 13:18:52 +00:00
Original commit message from CVS: Patch by: Jindrich Makovicka <jindrich.makivicka at itonis tv> * gst/matroska/ebml-read.c: (gst_ebml_read_peek_bytes), (gst_ebml_read_pull_bytes), (gst_ebml_read_element_id), (gst_ebml_read_element_length), (gst_ebml_read_buffer), (gst_ebml_read_bytes), (gst_ebml_read_uint), (gst_ebml_read_sint), (gst_ebml_read_float), (gst_ebml_read_ascii), (gst_ebml_read_binary): Don't create unnecessary sub-buffers all the time. Dramatically improves performance with multiple concurrently running matroskademux instances (#341818) (and avoids doing unnecessarily inefficient things in the general case).
834 lines
18 KiB
C
834 lines
18 KiB
C
/* GStreamer EBML I/O
|
|
* (c) 2003 Ronald Bultje <rbultje@ronald.bitfreak.net>
|
|
*
|
|
* ebml-read.c: read EBML data from file/stream
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "config.h"
|
|
#endif
|
|
|
|
#include <string.h>
|
|
|
|
#include "ebml-read.h"
|
|
#include "ebml-ids.h"
|
|
|
|
GST_DEBUG_CATEGORY_STATIC (ebmlread_debug);
|
|
#define GST_CAT_DEFAULT ebmlread_debug
|
|
|
|
static void gst_ebml_read_class_init (GstEbmlReadClass * klass);
|
|
static void gst_ebml_read_init (GstEbmlRead * ebml);
|
|
static GstStateChangeReturn gst_ebml_read_change_state (GstElement * element,
|
|
GstStateChange transition);
|
|
|
|
/* convenience functions */
|
|
static gboolean gst_ebml_read_peek_bytes (GstEbmlRead * ebml, guint size,
|
|
GstBuffer ** p_buf, guint8 ** bytes);
|
|
static gboolean gst_ebml_read_pull_bytes (GstEbmlRead * ebml, guint size,
|
|
GstBuffer ** p_buf, guint8 ** bytes);
|
|
|
|
|
|
static GstElementClass *parent_class; /* NULL */
|
|
|
|
GType
|
|
gst_ebml_read_get_type (void)
|
|
{
|
|
static GType gst_ebml_read_type; /* 0 */
|
|
|
|
if (!gst_ebml_read_type) {
|
|
static const GTypeInfo gst_ebml_read_info = {
|
|
sizeof (GstEbmlReadClass),
|
|
NULL,
|
|
NULL,
|
|
(GClassInitFunc) gst_ebml_read_class_init,
|
|
NULL,
|
|
NULL,
|
|
sizeof (GstEbmlRead),
|
|
0,
|
|
(GInstanceInitFunc) gst_ebml_read_init,
|
|
};
|
|
|
|
gst_ebml_read_type =
|
|
g_type_register_static (GST_TYPE_ELEMENT, "GstEbmlRead",
|
|
&gst_ebml_read_info, 0);
|
|
}
|
|
|
|
return gst_ebml_read_type;
|
|
}
|
|
|
|
static void
|
|
gst_ebml_read_class_init (GstEbmlReadClass * klass)
|
|
{
|
|
GstElementClass *gstelement_class = (GstElementClass *) klass;
|
|
|
|
parent_class = g_type_class_peek_parent (klass);
|
|
|
|
GST_DEBUG_CATEGORY_INIT (ebmlread_debug, "ebmlread",
|
|
0, "EBML stream helper class");
|
|
|
|
gstelement_class->change_state =
|
|
GST_DEBUG_FUNCPTR (gst_ebml_read_change_state);
|
|
}
|
|
|
|
static void
|
|
gst_ebml_read_init (GstEbmlRead * ebml)
|
|
{
|
|
ebml->sinkpad = NULL;
|
|
ebml->level = NULL;
|
|
}
|
|
|
|
static GstStateChangeReturn
|
|
gst_ebml_read_change_state (GstElement * element, GstStateChange transition)
|
|
{
|
|
GstStateChangeReturn ret;
|
|
GstEbmlRead *ebml = GST_EBML_READ (element);
|
|
|
|
switch (transition) {
|
|
case GST_STATE_CHANGE_READY_TO_PAUSED:
|
|
if (!ebml->sinkpad) {
|
|
g_return_val_if_reached (GST_STATE_CHANGE_FAILURE);
|
|
}
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
|
|
|
|
switch (transition) {
|
|
case GST_STATE_CHANGE_PAUSED_TO_READY:
|
|
{
|
|
g_list_foreach (ebml->level, (GFunc) g_free, NULL);
|
|
g_list_free (ebml->level);
|
|
ebml->level = NULL;
|
|
if (ebml->cached_buffer) {
|
|
gst_buffer_unref (ebml->cached_buffer);
|
|
ebml->cached_buffer = NULL;
|
|
}
|
|
ebml->offset = 0;
|
|
break;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Return: the amount of levels in the hierarchy that the
|
|
* current element lies higher than the previous one.
|
|
* The opposite isn't done - that's auto-done using master
|
|
* element reading.
|
|
*/
|
|
|
|
static guint
|
|
gst_ebml_read_element_level_up (GstEbmlRead * ebml)
|
|
{
|
|
guint num = 0;
|
|
guint64 pos = ebml->offset;
|
|
|
|
while (ebml->level != NULL) {
|
|
GList *last = g_list_last (ebml->level);
|
|
GstEbmlLevel *level = last->data;
|
|
|
|
if (pos >= level->start + level->length) {
|
|
ebml->level = g_list_remove (ebml->level, level);
|
|
g_free (level);
|
|
num++;
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
|
|
return num;
|
|
}
|
|
|
|
/*
|
|
* Calls pull_range for (offset,size) without advancing our offset
|
|
*/
|
|
static gboolean
|
|
gst_ebml_read_peek_bytes (GstEbmlRead * ebml, guint size, GstBuffer ** p_buf,
|
|
guint8 ** bytes)
|
|
{
|
|
GstFlowReturn ret;
|
|
|
|
/* Caching here actually makes much less difference than one would expect.
|
|
* We do it mainly to avoid pulling buffers of 1 byte all the time */
|
|
if (ebml->cached_buffer) {
|
|
guint64 cache_offset = GST_BUFFER_OFFSET (ebml->cached_buffer);
|
|
guint cache_size = GST_BUFFER_SIZE (ebml->cached_buffer);
|
|
|
|
if (cache_offset <= ebml->offset &&
|
|
(ebml->offset + size) < (cache_offset + cache_size)) {
|
|
if (p_buf)
|
|
*p_buf = gst_buffer_create_sub (ebml->cached_buffer,
|
|
ebml->offset - cache_offset, size);
|
|
if (bytes)
|
|
*bytes =
|
|
GST_BUFFER_DATA (ebml->cached_buffer) + ebml->offset - cache_offset;
|
|
return TRUE;
|
|
}
|
|
gst_buffer_unref (ebml->cached_buffer);
|
|
ebml->cached_buffer = NULL;
|
|
}
|
|
|
|
if (gst_pad_pull_range (ebml->sinkpad, ebml->offset, MAX (size, 64 * 1024),
|
|
&ebml->cached_buffer) == GST_FLOW_OK &&
|
|
GST_BUFFER_SIZE (ebml->cached_buffer) >= size) {
|
|
if (p_buf)
|
|
*p_buf = gst_buffer_create_sub (ebml->cached_buffer, 0, size);
|
|
if (bytes)
|
|
*bytes = GST_BUFFER_DATA (ebml->cached_buffer);
|
|
return TRUE;
|
|
}
|
|
|
|
if (!p_buf)
|
|
return FALSE;
|
|
|
|
ret = gst_pad_pull_range (ebml->sinkpad, ebml->offset, size, p_buf);
|
|
if (ret != GST_FLOW_OK) {
|
|
GST_DEBUG ("pull_range returned %d", ret);
|
|
return FALSE;
|
|
}
|
|
|
|
if (GST_BUFFER_SIZE (*p_buf) < size) {
|
|
GST_WARNING_OBJECT (ebml, "Dropping short buffer at offset %"
|
|
G_GUINT64_FORMAT ": wanted %u bytes, got %u bytes", ebml->offset,
|
|
size, GST_BUFFER_SIZE (*p_buf));
|
|
gst_buffer_unref (*p_buf);
|
|
*p_buf = NULL;
|
|
if (bytes)
|
|
*bytes = NULL;
|
|
return FALSE;
|
|
}
|
|
|
|
if (bytes)
|
|
*bytes = GST_BUFFER_DATA (*p_buf);
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Calls pull_range for (offset,size) and advances our offset by size
|
|
*/
|
|
static gboolean
|
|
gst_ebml_read_pull_bytes (GstEbmlRead * ebml, guint size, GstBuffer ** p_buf,
|
|
guint8 ** bytes)
|
|
{
|
|
if (!gst_ebml_read_peek_bytes (ebml, size, p_buf, bytes))
|
|
return FALSE;
|
|
|
|
ebml->offset += size;
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Read: the element content data ID.
|
|
* Return: FALSE on error.
|
|
*/
|
|
|
|
static gboolean
|
|
gst_ebml_read_element_id (GstEbmlRead * ebml, guint32 * id, guint * level_up)
|
|
{
|
|
guint8 *buf;
|
|
gint len_mask = 0x80, read = 1, n = 1;
|
|
guint32 total;
|
|
guint8 b;
|
|
|
|
if (!gst_ebml_read_peek_bytes (ebml, 1, NULL, &buf))
|
|
return FALSE;
|
|
|
|
b = GST_READ_UINT8 (buf);
|
|
|
|
total = (guint32) b;
|
|
|
|
while (read <= 4 && !(total & len_mask)) {
|
|
read++;
|
|
len_mask >>= 1;
|
|
}
|
|
if (read > 4) {
|
|
guint64 pos = ebml->offset;
|
|
|
|
GST_ELEMENT_ERROR (ebml, STREAM, DEMUX, (NULL),
|
|
("Invalid EBML ID size tag (0x%x) at position %llu (0x%llx)",
|
|
(guint) b, pos, pos));
|
|
return FALSE;
|
|
}
|
|
|
|
if (!gst_ebml_read_peek_bytes (ebml, read, NULL, &buf))
|
|
return FALSE;
|
|
|
|
while (n < read) {
|
|
b = GST_READ_UINT8 (buf + n);
|
|
total = (total << 8) | b;
|
|
++n;
|
|
}
|
|
|
|
*id = total;
|
|
|
|
/* level */
|
|
if (level_up)
|
|
*level_up = gst_ebml_read_element_level_up (ebml);
|
|
|
|
ebml->offset += read;
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Read: element content length.
|
|
* Return: the number of bytes read or -1 on error.
|
|
*/
|
|
|
|
static gint
|
|
gst_ebml_read_element_length (GstEbmlRead * ebml, guint64 * length)
|
|
{
|
|
guint8 *buf;
|
|
gint len_mask = 0x80, read = 1, n = 1, num_ffs = 0;
|
|
guint64 total;
|
|
guint8 b;
|
|
|
|
if (!gst_ebml_read_peek_bytes (ebml, 1, NULL, &buf))
|
|
return -1;
|
|
|
|
b = GST_READ_UINT8 (buf);
|
|
|
|
total = (guint64) b;
|
|
|
|
while (read <= 8 && !(total & len_mask)) {
|
|
read++;
|
|
len_mask >>= 1;
|
|
}
|
|
if (read > 8) {
|
|
guint64 pos = ebml->offset;
|
|
|
|
GST_ELEMENT_ERROR (ebml, STREAM, DEMUX, (NULL),
|
|
("Invalid EBML length size tag (0x%x) at position %llu (0x%llx)",
|
|
(guint) b, pos, pos));
|
|
return -1;
|
|
}
|
|
|
|
if ((total &= (len_mask - 1)) == len_mask - 1)
|
|
num_ffs++;
|
|
|
|
if (!gst_ebml_read_peek_bytes (ebml, read, NULL, &buf))
|
|
return -1;
|
|
|
|
while (n < read) {
|
|
guint8 b = GST_READ_UINT8 (buf + n);
|
|
|
|
if (b == 0xff)
|
|
num_ffs++;
|
|
total = (total << 8) | b;
|
|
++n;
|
|
}
|
|
|
|
if (read == num_ffs)
|
|
*length = G_MAXUINT64;
|
|
else
|
|
*length = total;
|
|
|
|
ebml->offset += read;
|
|
|
|
return read;
|
|
}
|
|
|
|
/*
|
|
* Return: the ID of the next element.
|
|
* Level_up contains the amount of levels that this
|
|
* next element lies higher than the previous one.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_peek_id (GstEbmlRead * ebml, guint * level_up, guint32 * id)
|
|
{
|
|
guint64 off;
|
|
|
|
g_assert (level_up);
|
|
|
|
off = ebml->offset; /* save offset */
|
|
|
|
if (!gst_ebml_read_element_id (ebml, id, level_up))
|
|
return FALSE;
|
|
|
|
ebml->offset = off; /* restore offset */
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Return the length of the stream in bytes
|
|
*/
|
|
|
|
gint64
|
|
gst_ebml_read_get_length (GstEbmlRead * ebml)
|
|
{
|
|
GstFormat fmt = GST_FORMAT_BYTES;
|
|
gint64 end;
|
|
|
|
if (!gst_pad_query_duration (GST_PAD_PEER (ebml->sinkpad), &fmt, &end))
|
|
g_return_val_if_reached (0); ///// FIXME /////////
|
|
|
|
if (fmt != GST_FORMAT_BYTES || end < 0)
|
|
g_return_val_if_reached (0); ///// FIXME /////////
|
|
|
|
return end;
|
|
}
|
|
|
|
/*
|
|
* Seek to a given offset.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_seek (GstEbmlRead * ebml, guint64 offset)
|
|
{
|
|
if (offset >= gst_ebml_read_get_length (ebml))
|
|
return FALSE;
|
|
|
|
ebml->offset = offset;
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Skip the next element.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_skip (GstEbmlRead * ebml)
|
|
{
|
|
guint64 length;
|
|
guint32 id;
|
|
|
|
if (!gst_ebml_read_element_id (ebml, &id, NULL))
|
|
return FALSE;
|
|
|
|
if (gst_ebml_read_element_length (ebml, &length) < 0)
|
|
return FALSE;
|
|
|
|
ebml->offset += length;
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Read the next element as a GstBuffer (binary).
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_buffer (GstEbmlRead * ebml, guint32 * id, GstBuffer ** buf)
|
|
{
|
|
guint64 length;
|
|
|
|
if (!gst_ebml_read_element_id (ebml, id, NULL))
|
|
return FALSE;
|
|
|
|
if (gst_ebml_read_element_length (ebml, &length) < 0)
|
|
return FALSE;
|
|
|
|
if (length == 0) {
|
|
*buf = gst_buffer_new ();
|
|
return TRUE;
|
|
}
|
|
|
|
*buf = NULL;
|
|
if (!gst_ebml_read_pull_bytes (ebml, (guint) length, buf, NULL))
|
|
return FALSE;
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Read the next element, return a pointer to it and its size.
|
|
*/
|
|
|
|
static gboolean
|
|
gst_ebml_read_bytes (GstEbmlRead * ebml, guint32 * id, guint8 ** data,
|
|
guint * size)
|
|
{
|
|
guint64 length;
|
|
|
|
*size = 0;
|
|
|
|
if (!gst_ebml_read_element_id (ebml, id, NULL))
|
|
return FALSE;
|
|
|
|
if (gst_ebml_read_element_length (ebml, &length) < 0)
|
|
return FALSE;
|
|
|
|
if (length == 0) {
|
|
*data = NULL;
|
|
return TRUE;
|
|
}
|
|
|
|
*data = NULL;
|
|
if (!gst_ebml_read_pull_bytes (ebml, (guint) length, NULL, data))
|
|
return FALSE;
|
|
|
|
*size = (guint) length;
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Read the next element as an unsigned int.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_uint (GstEbmlRead * ebml, guint32 * id, guint64 * num)
|
|
{
|
|
guint8 *data;
|
|
guint size;
|
|
|
|
if (!gst_ebml_read_bytes (ebml, id, &data, &size))
|
|
return FALSE;
|
|
|
|
if (size < 1 || size > 8) {
|
|
GST_ELEMENT_ERROR (ebml, STREAM, DEMUX, (NULL),
|
|
("Invalid integer element size %d at position %llu (0x%llu)",
|
|
size, ebml->offset - size, ebml->offset - size));
|
|
return FALSE;
|
|
}
|
|
*num = 0;
|
|
while (size > 0) {
|
|
*num = (*num << 8) | *data;
|
|
size--;
|
|
data++;
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Read the next element as a signed int.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_sint (GstEbmlRead * ebml, guint32 * id, gint64 * num)
|
|
{
|
|
guint8 *data;
|
|
guint size;
|
|
gboolean negative = 0;
|
|
|
|
if (!gst_ebml_read_bytes (ebml, id, &data, &size))
|
|
return FALSE;
|
|
|
|
if (size < 1 || size > 8) {
|
|
GST_ELEMENT_ERROR (ebml, STREAM, DEMUX, (NULL),
|
|
("Invalid integer element size %d at position %llu (0x%llx)",
|
|
size, ebml->offset - size, ebml->offset - size));
|
|
return FALSE;
|
|
}
|
|
|
|
*num = 0;
|
|
if (*data & 0x80) {
|
|
negative = 1;
|
|
*num = *data & ~0x80;
|
|
size--;
|
|
data++;
|
|
}
|
|
|
|
while (size > 0) {
|
|
*num = (*num << 8) | *data;
|
|
size--;
|
|
data++;
|
|
}
|
|
|
|
/* make signed */
|
|
if (negative) {
|
|
*num = 0 - *num;
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Read the next element as a float.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_float (GstEbmlRead * ebml, guint32 * id, gdouble * num)
|
|
{
|
|
guint8 *data;
|
|
guint size;
|
|
|
|
if (!gst_ebml_read_bytes (ebml, id, &data, &size))
|
|
return FALSE;
|
|
|
|
if (size != 4 && size != 8 && size != 10) {
|
|
GST_ELEMENT_ERROR (ebml, STREAM, DEMUX, (NULL),
|
|
("Invalid float element size %d at position %llu (0x%llx)",
|
|
size, ebml->offset - size, ebml->offset - size));
|
|
return FALSE;
|
|
}
|
|
|
|
if (size == 10) {
|
|
GST_ELEMENT_ERROR (ebml, CORE, NOT_IMPLEMENTED, (NULL),
|
|
("FIXME! 10-byte floats unimplemented"));
|
|
return FALSE;
|
|
}
|
|
|
|
if (size == 4) {
|
|
gfloat f;
|
|
|
|
#if (G_BYTE_ORDER == G_BIG_ENDIAN)
|
|
f = *(gfloat *) data;
|
|
#else
|
|
while (size > 0) {
|
|
((guint8 *) & f)[size - 1] = data[4 - size];
|
|
size--;
|
|
}
|
|
#endif
|
|
|
|
*num = f;
|
|
} else {
|
|
gdouble d;
|
|
|
|
#if (G_BYTE_ORDER == G_BIG_ENDIAN)
|
|
d = *(gdouble *) data;
|
|
#else
|
|
while (size > 0) {
|
|
((guint8 *) & d)[size - 1] = data[8 - size];
|
|
size--;
|
|
}
|
|
#endif
|
|
|
|
*num = d;
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Read the next element as an ASCII string.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_ascii (GstEbmlRead * ebml, guint32 * id, gchar ** str)
|
|
{
|
|
guint8 *data;
|
|
guint size;
|
|
|
|
if (!gst_ebml_read_bytes (ebml, id, &data, &size))
|
|
return FALSE;
|
|
|
|
*str = g_malloc (size + 1);
|
|
memcpy (*str, data, size);
|
|
(*str)[size] = '\0';
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Read the next element as a UTF-8 string.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_utf8 (GstEbmlRead * ebml, guint32 * id, gchar ** str)
|
|
{
|
|
gboolean ret;
|
|
|
|
#ifndef GST_DISABLE_GST_DEBUG
|
|
guint64 oldoff = ebml->offset;
|
|
#endif
|
|
|
|
ret = gst_ebml_read_ascii (ebml, id, str);
|
|
|
|
if (str != NULL && *str != NULL && **str != '\0' &&
|
|
!g_utf8_validate (*str, -1, NULL)) {
|
|
GST_WARNING ("Invalid UTF-8 string at offset %" G_GUINT64_FORMAT, oldoff);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Read the next element as a date.
|
|
* Returns the seconds since the unix epoch.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_date (GstEbmlRead * ebml, guint32 * id, gint64 * date)
|
|
{
|
|
gint64 ebml_date;
|
|
gboolean res = gst_ebml_read_sint (ebml, id, &ebml_date);
|
|
|
|
*date = (ebml_date / GST_SECOND) + GST_EBML_DATE_OFFSET;
|
|
return res;
|
|
}
|
|
|
|
/*
|
|
* Read the next element, but only the header. The contents
|
|
* are supposed to be sub-elements which can be read separately.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_master (GstEbmlRead * ebml, guint32 * id)
|
|
{
|
|
GstEbmlLevel *level;
|
|
guint64 length;
|
|
|
|
if (!gst_ebml_read_element_id (ebml, id, NULL))
|
|
return FALSE;
|
|
|
|
if (gst_ebml_read_element_length (ebml, &length) < 0)
|
|
return FALSE;
|
|
|
|
/* remember level */
|
|
level = g_new (GstEbmlLevel, 1);
|
|
level->start = ebml->offset;
|
|
level->length = length;
|
|
ebml->level = g_list_append (ebml->level, level);
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Read the next element as binary data.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_binary (GstEbmlRead * ebml,
|
|
guint32 * id, guint8 ** binary, guint64 * length)
|
|
{
|
|
guint8 *data;
|
|
guint size;
|
|
|
|
if (!gst_ebml_read_bytes (ebml, id, &data, &size))
|
|
return FALSE;
|
|
|
|
*length = size;
|
|
*binary = g_memdup (data, size);
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Read an EBML header.
|
|
*/
|
|
|
|
gboolean
|
|
gst_ebml_read_header (GstEbmlRead * ebml, gchar ** doctype, guint * version)
|
|
{
|
|
/* this function is the first to be called */
|
|
guint32 id;
|
|
guint level_up;
|
|
|
|
/* default init */
|
|
if (doctype)
|
|
*doctype = NULL;
|
|
if (version)
|
|
*version = 1;
|
|
|
|
if (!gst_ebml_peek_id (ebml, &level_up, &id))
|
|
return FALSE;
|
|
|
|
GST_DEBUG_OBJECT (ebml, "id: %08x", GST_READ_UINT32_BE (&id));
|
|
|
|
if (level_up != 0 || id != GST_EBML_ID_HEADER) {
|
|
GST_ELEMENT_ERROR (ebml, STREAM, WRONG_TYPE, (NULL), (NULL));
|
|
return FALSE;
|
|
}
|
|
if (!gst_ebml_read_master (ebml, &id))
|
|
return FALSE;
|
|
|
|
while (TRUE) {
|
|
if (!gst_ebml_peek_id (ebml, &level_up, &id))
|
|
return FALSE;
|
|
|
|
/* end-of-header */
|
|
if (level_up)
|
|
break;
|
|
|
|
switch (id) {
|
|
/* is our read version uptodate? */
|
|
case GST_EBML_ID_EBMLREADVERSION:{
|
|
guint64 num;
|
|
|
|
if (!gst_ebml_read_uint (ebml, &id, &num))
|
|
return FALSE;
|
|
g_assert (id == GST_EBML_ID_EBMLREADVERSION);
|
|
if (num != GST_EBML_VERSION)
|
|
return FALSE;
|
|
break;
|
|
}
|
|
|
|
/* we only handle 8 byte lengths at max */
|
|
case GST_EBML_ID_EBMLMAXSIZELENGTH:{
|
|
guint64 num;
|
|
|
|
if (!gst_ebml_read_uint (ebml, &id, &num))
|
|
return FALSE;
|
|
g_assert (id == GST_EBML_ID_EBMLMAXSIZELENGTH);
|
|
if (num != sizeof (guint64))
|
|
return FALSE;
|
|
break;
|
|
}
|
|
|
|
/* we handle 4 byte IDs at max */
|
|
case GST_EBML_ID_EBMLMAXIDLENGTH:{
|
|
guint64 num;
|
|
|
|
if (!gst_ebml_read_uint (ebml, &id, &num))
|
|
return FALSE;
|
|
g_assert (id == GST_EBML_ID_EBMLMAXIDLENGTH);
|
|
if (num != sizeof (guint32))
|
|
return FALSE;
|
|
break;
|
|
}
|
|
|
|
case GST_EBML_ID_DOCTYPE:{
|
|
gchar *text;
|
|
|
|
if (!gst_ebml_read_ascii (ebml, &id, &text))
|
|
return FALSE;
|
|
g_assert (id == GST_EBML_ID_DOCTYPE);
|
|
if (doctype) {
|
|
if (doctype)
|
|
g_free (*doctype);
|
|
*doctype = text;
|
|
} else
|
|
g_free (text);
|
|
break;
|
|
}
|
|
|
|
case GST_EBML_ID_DOCTYPEREADVERSION:{
|
|
guint64 num;
|
|
|
|
if (!gst_ebml_read_uint (ebml, &id, &num))
|
|
return FALSE;
|
|
g_assert (id == GST_EBML_ID_DOCTYPEREADVERSION);
|
|
if (version)
|
|
*version = num;
|
|
break;
|
|
}
|
|
|
|
default:
|
|
GST_WARNING ("Unknown data type 0x%x in EBML header (ignored)", id);
|
|
/* pass-through */
|
|
|
|
/* we ignore these two, as they don't tell us anything we care about */
|
|
case GST_EBML_ID_VOID:
|
|
case GST_EBML_ID_EBMLVERSION:
|
|
case GST_EBML_ID_DOCTYPEVERSION:
|
|
if (!gst_ebml_read_skip (ebml))
|
|
return FALSE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
return TRUE;
|
|
}
|