gstreamer/ext/bz2/gstbz2dec.c
2012-03-18 18:32:41 +01:00

308 lines
8.1 KiB
C

/* GStreamer bz2 decoder
* Copyright (C) 2006 Lutz Müller <lutz topfrose de>
* 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 "gstbz2dec.h"
#include <gst/base/gsttypefindhelper.h>
#include <bzlib.h>
#include <string.h>
GST_DEBUG_CATEGORY_STATIC (bz2dec_debug);
#define GST_CAT_DEFAULT bz2dec_debug
static GstStaticPadTemplate sink_template =
GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-bzip"));
static GstStaticPadTemplate src_template =
GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
struct _GstBz2dec
{
GstElement parent;
GstPad *sink;
GstPad *src;
/* Properties */
guint first_buffer_size;
guint buffer_size;
gboolean ready;
bz_stream stream;
guint64 offset;
};
struct _GstBz2decClass
{
GstElementClass parent_class;
};
#define gst_bz2dec_parent_class parent_class
G_DEFINE_TYPE (GstBz2dec, gst_bz2dec, GST_TYPE_ELEMENT);
#define DEFAULT_FIRST_BUFFER_SIZE 1024
#define DEFAULT_BUFFER_SIZE 1024
enum
{
PROP_0,
PROP_FIRST_BUFFER_SIZE,
PROP_BUFFER_SIZE
};
static void
gst_bz2dec_decompress_end (GstBz2dec * b)
{
g_return_if_fail (GST_IS_BZ2DEC (b));
if (b->ready) {
BZ2_bzDecompressEnd (&b->stream);
memset (&b->stream, 0, sizeof (b->stream));
b->ready = FALSE;
}
}
static void
gst_bz2dec_decompress_init (GstBz2dec * b)
{
g_return_if_fail (GST_IS_BZ2DEC (b));
gst_bz2dec_decompress_end (b);
b->offset = 0;
switch (BZ2_bzDecompressInit (&b->stream, 0, 0)) {
case BZ_OK:
b->ready = TRUE;
return;
default:
b->ready = FALSE;
GST_ELEMENT_ERROR (b, CORE, FAILED, (NULL),
("Failed to start decompression."));
return;
}
}
static GstFlowReturn
gst_bz2dec_chain (GstPad * pad, GstObject * parent, GstBuffer * in)
{
GstFlowReturn flow;
GstBuffer *out;
GstBz2dec *b;
int r = BZ_OK;
GstMapInfo map, omap;
b = GST_BZ2DEC (parent);
if (!b->ready)
goto not_ready;
gst_buffer_map (in, &map, GST_MAP_READ);
b->stream.next_in = (char *) map.data;
b->stream.avail_in = map.size;
do {
guint n;
/* Create the output buffer */
out =
gst_buffer_new_and_alloc (b->offset ? b->buffer_size : b->
first_buffer_size);
/* Decode */
gst_buffer_map (out, &omap, GST_MAP_WRITE);
b->stream.next_out = (char *) omap.data;
b->stream.avail_out = omap.size;
r = BZ2_bzDecompress (&b->stream);
gst_buffer_unmap (out, &omap);
if ((r != BZ_OK) && (r != BZ_STREAM_END))
goto decode_failed;
if (b->stream.avail_out >= gst_buffer_get_size (out)) {
gst_buffer_unref (out);
break;
}
gst_buffer_resize (out, 0, gst_buffer_get_size (out) - b->stream.avail_out);
GST_BUFFER_OFFSET (out) =
b->stream.total_out_lo32 - gst_buffer_get_size (out);
/* Configure source pad (if necessary) */
if (!b->offset) {
GstCaps *caps = NULL;
caps = gst_type_find_helper_for_buffer (GST_OBJECT (b), out, NULL);
if (caps) {
gst_pad_set_caps (b->src, caps);
gst_pad_use_fixed_caps (b->src);
gst_caps_unref (caps);
} else {
/* FIXME: shouldn't we queue output buffers until we have a type? */
}
}
/* Push data */
n = gst_buffer_get_size (out);
flow = gst_pad_push (b->src, out);
if (flow != GST_FLOW_OK)
break;
b->offset += n;
} while (r != BZ_STREAM_END);
done:
gst_buffer_unmap (in, &map);
gst_buffer_unref (in);
return flow;
/* ERRORS */
decode_failed:
{
GST_ELEMENT_ERROR (b, STREAM, DECODE, (NULL),
("Failed to decompress data (error code %i).", r));
gst_bz2dec_decompress_init (b);
gst_buffer_unref (out);
flow = GST_FLOW_ERROR;
goto done;
}
not_ready:
{
GST_ELEMENT_ERROR (b, LIBRARY, FAILED, (NULL), ("Decompressor not ready."));
flow = GST_FLOW_FLUSHING;
goto done;
}
}
static void
gst_bz2dec_init (GstBz2dec * b)
{
b->first_buffer_size = DEFAULT_FIRST_BUFFER_SIZE;
b->buffer_size = DEFAULT_BUFFER_SIZE;
b->sink = gst_pad_new_from_static_template (&sink_template, "sink");
gst_pad_set_chain_function (b->sink, GST_DEBUG_FUNCPTR (gst_bz2dec_chain));
gst_element_add_pad (GST_ELEMENT (b), b->sink);
b->src = gst_pad_new_from_static_template (&src_template, "src");
gst_element_add_pad (GST_ELEMENT (b), b->src);
gst_pad_use_fixed_caps (b->src);
gst_bz2dec_decompress_init (b);
}
static void
gst_bz2dec_finalize (GObject * object)
{
GstBz2dec *b = GST_BZ2DEC (object);
gst_bz2dec_decompress_end (b);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static void
gst_bz2dec_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstBz2dec *b = GST_BZ2DEC (object);
switch (prop_id) {
case PROP_BUFFER_SIZE:
g_value_set_uint (value, b->buffer_size);
break;
case PROP_FIRST_BUFFER_SIZE:
g_value_set_uint (value, b->first_buffer_size);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
}
}
static void
gst_bz2dec_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstBz2dec *b = GST_BZ2DEC (object);
switch (prop_id) {
case PROP_BUFFER_SIZE:
b->buffer_size = g_value_get_uint (value);
break;
case PROP_FIRST_BUFFER_SIZE:
b->first_buffer_size = g_value_get_uint (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
}
}
static GstStateChangeReturn
gst_bz2dec_change_state (GstElement * element, GstStateChange transition)
{
GstBz2dec *b = GST_BZ2DEC (element);
GstStateChangeReturn ret;
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
if (ret != GST_STATE_CHANGE_SUCCESS)
return ret;
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
gst_bz2dec_decompress_init (b);
break;
default:
break;
}
return ret;
}
static void
gst_bz2dec_class_init (GstBz2decClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
gstelement_class->change_state = GST_DEBUG_FUNCPTR (gst_bz2dec_change_state);
gobject_class->finalize = gst_bz2dec_finalize;
gobject_class->get_property = gst_bz2dec_get_property;
gobject_class->set_property = gst_bz2dec_set_property;
g_object_class_install_property (G_OBJECT_CLASS (klass),
PROP_FIRST_BUFFER_SIZE, g_param_spec_uint ("first-buffer-size",
"Size of first buffer", "Size of first buffer (used to determine the "
"mime type of the uncompressed data)", 1, G_MAXUINT,
DEFAULT_FIRST_BUFFER_SIZE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_BUFFER_SIZE,
g_param_spec_uint ("buffer-size", "Buffer size", "Buffer size",
1, G_MAXUINT, DEFAULT_BUFFER_SIZE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&sink_template));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&src_template));
gst_element_class_set_details_simple (gstelement_class, "BZ2 decoder",
"Codec/Decoder", "Decodes compressed streams",
"Lutz Mueller <lutz@users.sourceforge.net>");
GST_DEBUG_CATEGORY_INIT (bz2dec_debug, "bz2dec", 0, "BZ2 decompressor");
}