gstreamer/subprojects/gst-plugins-good/gst/matroska/ebml-read.h

171 lines
5.8 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifndef __GST_EBML_READ_H__
#define __GST_EBML_READ_H__
#include <gst/gst.h>
#include <gst/base/gstbytereader.h>
G_BEGIN_DECLS
#define GST_TYPE_EBML_READ \
(gst_ebml_read_get_type ())
#define GST_EBML_READ(obj) \
(G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_EBML_READ, GstEbmlRead))
#define GST_EBML_READ_CLASS(klass) \
(G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_EBML_READ, GstEbmlReadClass))
#define GST_IS_EBML_READ(obj) \
(G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_EBML_READ))
#define GST_IS_EBML_READ_CLASS(klass) \
(G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_EBML_READ))
#define GST_EBML_READ_GET_CLASS(obj) \
(G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_EBML_READ, GstEbmlReadClass))
GST_DEBUG_CATEGORY_EXTERN (ebmlread_debug);
/* custom flow return code */
#define GST_FLOW_PARSE GST_FLOW_CUSTOM_ERROR
typedef struct _GstEbmlMaster {
guint64 offset;
GstByteReader br;
} GstEbmlMaster;
typedef struct _GstEbmlRead {
GstElement *el;
GstBuffer *buf;
guint64 offset;
GstMapInfo map;
GArray *readers;
} GstEbmlRead;
typedef GstFlowReturn (*GstPeekData) (gpointer * context, guint peek, const guint8 ** data);
/* returns UNEXPECTED if not enough data */
GstFlowReturn gst_ebml_peek_id_length (guint32 * _id, guint64 * _length,
guint * _needed,
GstPeekData peek, gpointer * ctx,
GstElement * el, guint64 offset);
void gst_ebml_read_init (GstEbmlRead * ebml,
GstElement * el, GstBuffer * buf,
guint64 offset);
void gst_ebml_read_clear (GstEbmlRead * ebml);
GstFlowReturn gst_ebml_peek_id (GstEbmlRead * ebml, guint32 * id);
/* return _PARSE if not enough data to read what is needed, _ERROR or _OK */
GstFlowReturn gst_ebml_read_skip (GstEbmlRead *ebml);
GstFlowReturn gst_ebml_read_buffer (GstEbmlRead *ebml,
guint32 *id,
GstBuffer **buf);
GstFlowReturn gst_ebml_read_uint (GstEbmlRead *ebml,
guint32 *id,
guint64 *num);
GstFlowReturn gst_ebml_read_sint (GstEbmlRead *ebml,
guint32 *id,
gint64 *num);
GstFlowReturn gst_ebml_read_float (GstEbmlRead *ebml,
guint32 *id,
gdouble *num);
GstFlowReturn gst_ebml_read_ascii (GstEbmlRead *ebml,
guint32 *id,
gchar **str);
GstFlowReturn gst_ebml_read_utf8 (GstEbmlRead *ebml,
guint32 *id,
gchar **str);
GstFlowReturn gst_ebml_read_date (GstEbmlRead *ebml,
guint32 *id,
gint64 *date);
GstFlowReturn gst_ebml_read_master (GstEbmlRead *ebml,
guint32 *id);
GstFlowReturn gst_ebml_read_pop_master (GstEbmlRead *ebml);
GstFlowReturn gst_ebml_read_binary (GstEbmlRead *ebml,
guint32 *id,
guint8 **binary,
guint64 *length);
GstFlowReturn gst_ebml_read_header (GstEbmlRead *read,
gchar **doctype,
guint *version);
/* Returns current (absolute) position of Ebml parser,
* i.e. taking into account offset provided at init */
static inline guint64
gst_ebml_read_get_pos (GstEbmlRead * ebml)
{
GstEbmlMaster *m;
g_return_val_if_fail (ebml->readers, 0);
g_return_val_if_fail (ebml->readers->len, 0);
m = &(g_array_index (ebml->readers, GstEbmlMaster, ebml->readers->len - 1));
return m->offset + gst_byte_reader_get_pos (&m->br);
}
/* Returns starting offset of Ebml parser */
static inline guint64
gst_ebml_read_get_offset (GstEbmlRead * ebml)
{
return ebml->offset;
}
static inline GstByteReader *
gst_ebml_read_br (GstEbmlRead * ebml)
{
g_return_val_if_fail (ebml->readers, NULL);
g_return_val_if_fail (ebml->readers->len, NULL);
return &(g_array_index (ebml->readers,
GstEbmlMaster, ebml->readers->len - 1).br);
}
static inline gboolean
gst_ebml_read_has_remaining (GstEbmlRead * ebml, guint64 bytes_needed,
gboolean auto_pop)
{
gboolean res;
res = (gst_byte_reader_get_remaining (gst_ebml_read_br (ebml)) >= bytes_needed);
if (G_LIKELY (!res && auto_pop)) {
gst_ebml_read_pop_master (ebml);
}
return G_LIKELY (res);
}
G_END_DECLS
#endif /* __GST_EBML_READ_H__ */