1 /* GStreamer bz2 decoder
2 * Copyright (C) 2006 Lutz Müller <lutz topfrose de>
3
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 */
19 #ifdef HAVE_CONFIG_H
20 #include "config.h"
21 #endif
22 #include "gstbz2dec.h"
23
24 #include <gst/base/gsttypefindhelper.h>
25
26 #include <bzlib.h>
27 #include <string.h>
28
29 GST_DEBUG_CATEGORY_STATIC (bz2dec_debug);
30 #define GST_CAT_DEFAULT bz2dec_debug
31
32 static GstStaticPadTemplate sink_template =
33 GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
34 GST_STATIC_CAPS ("application/x-bzip"));
35 static GstStaticPadTemplate src_template =
36 GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
37 GST_STATIC_CAPS_ANY);
38
39 struct _GstBz2dec
40 {
41 GstElement parent;
42
43 GstPad *sink;
44 GstPad *src;
45
46 /* Properties */
47 guint first_buffer_size;
48 guint buffer_size;
49
50 gboolean ready;
51 bz_stream stream;
52 guint64 offset;
53 };
54
55 struct _GstBz2decClass
56 {
57 GstElementClass parent_class;
58 };
59
60 #define gst_bz2dec_parent_class parent_class
61 G_DEFINE_TYPE (GstBz2dec, gst_bz2dec, GST_TYPE_ELEMENT);
62 GST_ELEMENT_REGISTER_DEFINE (bz2dec, "bz2dec", GST_RANK_NONE, GST_TYPE_BZ2DEC);
63
64 #define DEFAULT_FIRST_BUFFER_SIZE 1024
65 #define DEFAULT_BUFFER_SIZE 1024
66
67 enum
68 {
69 PROP_0,
70 PROP_FIRST_BUFFER_SIZE,
71 PROP_BUFFER_SIZE
72 };
73
74 static void
gst_bz2dec_decompress_end(GstBz2dec * b)75 gst_bz2dec_decompress_end (GstBz2dec * b)
76 {
77 g_return_if_fail (GST_IS_BZ2DEC (b));
78
79 if (b->ready) {
80 BZ2_bzDecompressEnd (&b->stream);
81 memset (&b->stream, 0, sizeof (b->stream));
82 b->ready = FALSE;
83 }
84 }
85
86 static void
gst_bz2dec_decompress_init(GstBz2dec * b)87 gst_bz2dec_decompress_init (GstBz2dec * b)
88 {
89 g_return_if_fail (GST_IS_BZ2DEC (b));
90
91 gst_bz2dec_decompress_end (b);
92 b->offset = 0;
93 switch (BZ2_bzDecompressInit (&b->stream, 0, 0)) {
94 case BZ_OK:
95 b->ready = TRUE;
96 return;
97 default:
98 b->ready = FALSE;
99 GST_ELEMENT_ERROR (b, CORE, FAILED, (NULL),
100 ("Failed to start decompression."));
101 return;
102 }
103 }
104
105 static GstFlowReturn
gst_bz2dec_chain(GstPad * pad,GstObject * parent,GstBuffer * in)106 gst_bz2dec_chain (GstPad * pad, GstObject * parent, GstBuffer * in)
107 {
108 GstFlowReturn flow = GST_FLOW_OK;
109 GstBuffer *out;
110 GstBz2dec *b;
111 int r = BZ_OK;
112 GstMapInfo map = GST_MAP_INFO_INIT, omap;
113
114 b = GST_BZ2DEC (parent);
115
116 if (!b->ready)
117 goto not_ready;
118
119 gst_buffer_map (in, &map, GST_MAP_READ);
120 b->stream.next_in = (char *) map.data;
121 b->stream.avail_in = map.size;
122
123 do {
124 guint n;
125
126 /* Create the output buffer */
127 out =
128 gst_buffer_new_and_alloc (b->offset ? b->buffer_size : b->
129 first_buffer_size);
130
131 /* Decode */
132 gst_buffer_map (out, &omap, GST_MAP_WRITE);
133 b->stream.next_out = (char *) omap.data;
134 b->stream.avail_out = omap.size;
135 r = BZ2_bzDecompress (&b->stream);
136 gst_buffer_unmap (out, &omap);
137 if ((r != BZ_OK) && (r != BZ_STREAM_END))
138 goto decode_failed;
139
140 if (b->stream.avail_out >= gst_buffer_get_size (out)) {
141 gst_buffer_unref (out);
142 break;
143 }
144 gst_buffer_resize (out, 0, gst_buffer_get_size (out) - b->stream.avail_out);
145 GST_BUFFER_OFFSET (out) =
146 b->stream.total_out_lo32 - gst_buffer_get_size (out);
147
148 /* Configure source pad (if necessary) */
149 if (!b->offset) {
150 GstCaps *caps = NULL;
151
152 caps = gst_type_find_helper_for_buffer (GST_OBJECT (b), out, NULL);
153 if (caps) {
154 gst_pad_set_caps (b->src, caps);
155 gst_pad_use_fixed_caps (b->src);
156 gst_caps_unref (caps);
157 } else {
158 /* FIXME: shouldn't we queue output buffers until we have a type? */
159 }
160 }
161
162 /* Push data */
163 n = gst_buffer_get_size (out);
164 flow = gst_pad_push (b->src, out);
165 if (flow != GST_FLOW_OK)
166 break;
167 b->offset += n;
168 } while (r != BZ_STREAM_END);
169
170 done:
171
172 gst_buffer_unmap (in, &map);
173 gst_buffer_unref (in);
174 return flow;
175
176 /* ERRORS */
177 decode_failed:
178 {
179 GST_ELEMENT_ERROR (b, STREAM, DECODE, (NULL),
180 ("Failed to decompress data (error code %i).", r));
181 gst_bz2dec_decompress_init (b);
182 gst_buffer_unref (out);
183 flow = GST_FLOW_ERROR;
184 goto done;
185 }
186 not_ready:
187 {
188 GST_ELEMENT_ERROR (b, LIBRARY, FAILED, (NULL), ("Decompressor not ready."));
189 flow = GST_FLOW_FLUSHING;
190 goto done;
191 }
192 }
193
194 static void
gst_bz2dec_init(GstBz2dec * b)195 gst_bz2dec_init (GstBz2dec * b)
196 {
197 b->first_buffer_size = DEFAULT_FIRST_BUFFER_SIZE;
198 b->buffer_size = DEFAULT_BUFFER_SIZE;
199
200 b->sink = gst_pad_new_from_static_template (&sink_template, "sink");
201 gst_pad_set_chain_function (b->sink, GST_DEBUG_FUNCPTR (gst_bz2dec_chain));
202 gst_element_add_pad (GST_ELEMENT (b), b->sink);
203
204 b->src = gst_pad_new_from_static_template (&src_template, "src");
205 gst_element_add_pad (GST_ELEMENT (b), b->src);
206 gst_pad_use_fixed_caps (b->src);
207
208 gst_bz2dec_decompress_init (b);
209 }
210
211 static void
gst_bz2dec_finalize(GObject * object)212 gst_bz2dec_finalize (GObject * object)
213 {
214 GstBz2dec *b = GST_BZ2DEC (object);
215
216 gst_bz2dec_decompress_end (b);
217
218 G_OBJECT_CLASS (parent_class)->finalize (object);
219 }
220
221 static void
gst_bz2dec_get_property(GObject * object,guint prop_id,GValue * value,GParamSpec * pspec)222 gst_bz2dec_get_property (GObject * object, guint prop_id,
223 GValue * value, GParamSpec * pspec)
224 {
225 GstBz2dec *b = GST_BZ2DEC (object);
226
227 switch (prop_id) {
228 case PROP_BUFFER_SIZE:
229 g_value_set_uint (value, b->buffer_size);
230 break;
231 case PROP_FIRST_BUFFER_SIZE:
232 g_value_set_uint (value, b->first_buffer_size);
233 break;
234 default:
235 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
236 }
237 }
238
239 static void
gst_bz2dec_set_property(GObject * object,guint prop_id,const GValue * value,GParamSpec * pspec)240 gst_bz2dec_set_property (GObject * object, guint prop_id,
241 const GValue * value, GParamSpec * pspec)
242 {
243 GstBz2dec *b = GST_BZ2DEC (object);
244
245 switch (prop_id) {
246 case PROP_BUFFER_SIZE:
247 b->buffer_size = g_value_get_uint (value);
248 break;
249 case PROP_FIRST_BUFFER_SIZE:
250 b->first_buffer_size = g_value_get_uint (value);
251 break;
252 default:
253 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
254 }
255 }
256
257 static GstStateChangeReturn
gst_bz2dec_change_state(GstElement * element,GstStateChange transition)258 gst_bz2dec_change_state (GstElement * element, GstStateChange transition)
259 {
260 GstBz2dec *b = GST_BZ2DEC (element);
261 GstStateChangeReturn ret;
262
263 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
264 if (ret != GST_STATE_CHANGE_SUCCESS)
265 return ret;
266
267 switch (transition) {
268 case GST_STATE_CHANGE_PAUSED_TO_READY:
269 gst_bz2dec_decompress_init (b);
270 break;
271 default:
272 break;
273 }
274 return ret;
275 }
276
277 static void
gst_bz2dec_class_init(GstBz2decClass * klass)278 gst_bz2dec_class_init (GstBz2decClass * klass)
279 {
280 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
281 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
282
283 gstelement_class->change_state = GST_DEBUG_FUNCPTR (gst_bz2dec_change_state);
284
285 gobject_class->finalize = gst_bz2dec_finalize;
286 gobject_class->get_property = gst_bz2dec_get_property;
287 gobject_class->set_property = gst_bz2dec_set_property;
288
289 g_object_class_install_property (G_OBJECT_CLASS (klass),
290 PROP_FIRST_BUFFER_SIZE, g_param_spec_uint ("first-buffer-size",
291 "Size of first buffer", "Size of first buffer (used to determine the "
292 "mime type of the uncompressed data)", 1, G_MAXUINT,
293 DEFAULT_FIRST_BUFFER_SIZE,
294 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
295 g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_BUFFER_SIZE,
296 g_param_spec_uint ("buffer-size", "Buffer size", "Buffer size",
297 1, G_MAXUINT, DEFAULT_BUFFER_SIZE,
298 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
299
300 gst_element_class_add_static_pad_template (gstelement_class, &sink_template);
301 gst_element_class_add_static_pad_template (gstelement_class, &src_template);
302 gst_element_class_set_static_metadata (gstelement_class, "BZ2 decoder",
303 "Codec/Decoder", "Decodes compressed streams",
304 "Lutz Mueller <lutz@users.sourceforge.net>");
305
306 GST_DEBUG_CATEGORY_INIT (bz2dec_debug, "bz2dec", 0, "BZ2 decompressor");
307 }
308