• Charles Kerr's avatar
    decoder/ffmpeg: fix crash on startup in mpd_ffmpeg_log_callback() · 6a958980
    Charles Kerr authored
    What's happening is the `ptr' argument to that function is NULL for me
    every time. `ptr' is unconditionally dereferenced to generate a log
    message, and this is where mpd crashes.
    
    Attached is a simple patch that tests for NULL and omits the log. With
    this patch the crash disappeared and mpd went back to working well.
    6a958980
ffmpeg_decoder_plugin.c 14.6 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588
/*
 * Copyright (C) 2003-2010 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "config.h"
#include "decoder_api.h"
#include "audio_check.h"

#include <glib.h>

#include <assert.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

#ifdef OLD_FFMPEG_INCLUDES
#include <avcodec.h>
#include <avformat.h>
#include <avio.h>
#else
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libavformat/avio.h>
#include <libavutil/log.h>
#endif

#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "ffmpeg"

#ifndef OLD_FFMPEG_INCLUDES

static GLogLevelFlags
level_ffmpeg_to_glib(int level)
{
	if (level <= AV_LOG_FATAL)
		return G_LOG_LEVEL_CRITICAL;

	if (level <= AV_LOG_ERROR)
		return G_LOG_LEVEL_WARNING;

	if (level <= AV_LOG_INFO)
		return G_LOG_LEVEL_MESSAGE;

	return G_LOG_LEVEL_DEBUG;
}

static void
mpd_ffmpeg_log_callback(G_GNUC_UNUSED void *ptr, int level,
			const char *fmt, va_list vl)
{
	const AVClass * cls = NULL;

	if (ptr != NULL)
		cls = *(const AVClass *const*)ptr;

	if (cls != NULL) {
		char *domain = g_strconcat(G_LOG_DOMAIN, "/", cls->item_name(ptr), NULL);
		g_logv(domain, level_ffmpeg_to_glib(level), fmt, vl);
		g_free(domain);
	}
}

#endif /* !OLD_FFMPEG_INCLUDES */

struct ffmpeg_stream {
	/** hack - see url_to_struct() */
	char url[64];

	struct decoder *decoder;
	struct input_stream *input;
};

/**
 * Convert a faked mpd:// URL to a ffmpeg_stream structure.  This is a
 * hack because ffmpeg does not provide a nice API for passing a
 * user-defined pointer to mpdurl_open().
 */
static struct ffmpeg_stream *url_to_struct(const char *url)
{
	union {
		const char *in;
		struct ffmpeg_stream *out;
	} u = { .in = url };
	return u.out;
}

static int mpd_ffmpeg_open(URLContext *h, const char *filename,
			   G_GNUC_UNUSED int flags)
{
	struct ffmpeg_stream *stream = url_to_struct(filename);
	h->priv_data = stream;
	h->is_streamed = stream->input->seekable ? 0 : 1;
	return 0;
}

static int mpd_ffmpeg_read(URLContext *h, unsigned char *buf, int size)
{
	struct ffmpeg_stream *stream = (struct ffmpeg_stream *) h->priv_data;

	return decoder_read(stream->decoder, stream->input,
			    (void *)buf, size);
}

static int64_t mpd_ffmpeg_seek(URLContext *h, int64_t pos, int whence)
{
	struct ffmpeg_stream *stream = (struct ffmpeg_stream *) h->priv_data;
	bool ret;

	if (whence == AVSEEK_SIZE)
		return stream->input->size;

	ret = input_stream_seek(stream->input, pos, whence, NULL);
	if (!ret)
		return -1;

	return stream->input->offset;
}

static int mpd_ffmpeg_close(URLContext *h)
{
	h->priv_data = NULL;
	return 0;
}

static URLProtocol mpd_ffmpeg_fileops = {
	.name = "mpd",
	.url_open = mpd_ffmpeg_open,
	.url_read = mpd_ffmpeg_read,
	.url_seek = mpd_ffmpeg_seek,
	.url_close = mpd_ffmpeg_close,
};

static bool
ffmpeg_init(G_GNUC_UNUSED const struct config_param *param)
{
#ifndef OLD_FFMPEG_INCLUDES
	av_log_set_callback(mpd_ffmpeg_log_callback);
#endif

	av_register_all();
	register_protocol(&mpd_ffmpeg_fileops);
	return true;
}

static int
ffmpeg_find_audio_stream(const AVFormatContext *format_context)
{
	for (unsigned i = 0; i < format_context->nb_streams; ++i)
		if (format_context->streams[i]->codec->codec_type ==
		    CODEC_TYPE_AUDIO)
			return i;

	return -1;
}

/**
 * Append the suffix of the original URI to the virtual stream URI.
 * Without this, libavformat cannot detect some of the codecs
 * (e.g. "shorten").
 */
static void
append_uri_suffix(struct ffmpeg_stream *stream, const char *uri)
{
	assert(stream != NULL);
	assert(uri != NULL);

	char *base = g_path_get_basename(uri);

	const char *suffix = strrchr(base, '.');
	if (suffix != NULL && suffix[1] != 0)
		g_strlcat(stream->url, suffix, sizeof(stream->url));

	g_free(base);
}

/**
 * On some platforms, libavcodec wants the output buffer aligned to 16
 * bytes (because it uses SSE/Altivec internally).  This function
 * returns the aligned version of the specified buffer, and corrects
 * the buffer size.
 */
static void *
align16(void *p, size_t *length_p)
{
	unsigned add = 16 - (size_t)p % 16;

	*length_p -= add;
	return (char *)p + add;
}

static enum decoder_command
ffmpeg_send_packet(struct decoder *decoder, struct input_stream *is,
		   const AVPacket *packet,
		   AVCodecContext *codec_context,
		   const AVRational *time_base)
{
	enum decoder_command cmd = DECODE_COMMAND_NONE;
	uint8_t audio_buf[(AVCODEC_MAX_AUDIO_FRAME_SIZE * 3) / 2 + 16];
	int16_t *aligned_buffer;
	size_t buffer_size;
	int len, audio_size;
	uint8_t *packet_data;
	int packet_size;

	if (packet->pts != (int64_t)AV_NOPTS_VALUE)
		decoder_timestamp(decoder,
				  av_rescale_q(packet->pts, *time_base,
					       (AVRational){1, 1}));

	packet_data = packet->data;
	packet_size = packet->size;

	buffer_size = sizeof(audio_buf);
	aligned_buffer = align16(audio_buf, &buffer_size);

	while ((packet_size > 0) && (cmd == DECODE_COMMAND_NONE)) {
		audio_size = buffer_size;
		len = avcodec_decode_audio2(codec_context,
					    aligned_buffer, &audio_size,
					    packet_data, packet_size);

		if (len < 0) {
			/* if error, we skip the frame */
			g_message("decoding failed\n");
			break;
		}

		packet_data += len;
		packet_size -= len;

		if (audio_size <= 0)
			continue;

		cmd = decoder_data(decoder, is,
				   aligned_buffer, audio_size,
				   codec_context->bit_rate / 1000);
	}
	return cmd;
}

static enum sample_format
ffmpeg_sample_format(G_GNUC_UNUSED const AVCodecContext *codec_context)
{
#if LIBAVCODEC_VERSION_INT >= ((51<<16)+(41<<8)+0)
	int bits = (uint8_t) av_get_bits_per_sample_format(codec_context->sample_fmt);

	/* XXX implement & test other sample formats */

	switch (bits) {
	case 16:
		return SAMPLE_FORMAT_S16;
	}

	return SAMPLE_FORMAT_UNDEFINED;
#else
	/* XXX fixme 16-bit for older ffmpeg (13 Aug 2007) */
	return SAMPLE_FORMAT_S16;
#endif
}

static void
ffmpeg_decode(struct decoder *decoder, struct input_stream *input)
{
	struct ffmpeg_stream stream = {
		.url = "mpd://X", /* only the mpd:// prefix matters */
		.decoder = decoder,
		.input = input,
	};
	AVFormatContext *format_context;
	AVCodecContext *codec_context;
	AVCodec *codec;
	int audio_stream;

	if (input->uri != NULL)
		append_uri_suffix(&stream, input->uri);

	//ffmpeg works with ours "fileops" helper
	if (av_open_input_file(&format_context, stream.url, NULL, 0, NULL) != 0) {
		g_warning("Open failed\n");
		return;
	}

	if (av_find_stream_info(format_context)<0) {
		g_warning("Couldn't find stream info\n");
		av_close_input_file(format_context);
		return;
	}

	audio_stream = ffmpeg_find_audio_stream(format_context);
	if (audio_stream == -1) {
		g_warning("No audio stream inside\n");
		av_close_input_file(format_context);
		return;
	}

	codec_context = format_context->streams[audio_stream]->codec;
	if (codec_context->codec_name[0] != 0)
		g_debug("codec '%s'", codec_context->codec_name);

	codec = avcodec_find_decoder(codec_context->codec_id);

	if (!codec) {
		g_warning("Unsupported audio codec\n");
		av_close_input_file(format_context);
		return;
	}

	if (avcodec_open(codec_context, codec)<0) {
		g_warning("Could not open codec\n");
		av_close_input_file(format_context);
		return;
	}

	GError *error = NULL;
	struct audio_format audio_format;
	if (!audio_format_init_checked(&audio_format,
				       codec_context->sample_rate,
				       ffmpeg_sample_format(codec_context),
				       codec_context->channels, &error)) {
		g_warning("%s", error->message);
		g_error_free(error);
		avcodec_close(codec_context);
		av_close_input_file(format_context);
		return;
	}

	int total_time = format_context->duration != (int64_t)AV_NOPTS_VALUE
		? format_context->duration / AV_TIME_BASE
		: 0;

	decoder_initialized(decoder, &audio_format,
			    input->seekable, total_time);

	enum decoder_command cmd;
	do {
		AVPacket packet;
		if (av_read_frame(format_context, &packet) < 0)
			/* end of file */
			break;

		if (packet.stream_index == audio_stream)
			cmd = ffmpeg_send_packet(decoder, input,
						 &packet, codec_context,
						 &format_context->streams[audio_stream]->time_base);
		else
			cmd = decoder_get_command(decoder);

		av_free_packet(&packet);

		if (cmd == DECODE_COMMAND_SEEK) {
			int64_t where =
				decoder_seek_where(decoder) * AV_TIME_BASE;

			if (av_seek_frame(format_context, -1, where, 0) < 0)
				decoder_seek_error(decoder);
			else
				decoder_command_finished(decoder);
		}
	} while (cmd != DECODE_COMMAND_STOP);

	avcodec_close(codec_context);
	av_close_input_file(format_context);
}

#if LIBAVFORMAT_VERSION_INT >= ((52<<16)+(31<<8)+0)
static bool
ffmpeg_copy_metadata(struct tag *tag, AVMetadata *m,
		     enum tag_type type, const char *name)
{
	AVMetadataTag *mt = NULL;

	while ((mt = av_metadata_get(m, name, mt, 0)) != NULL)
		tag_add_item(tag, type, mt->value);
	return mt != NULL;
}
#endif

//no tag reading in ffmpeg, check if playable
static struct tag *
ffmpeg_stream_tag(struct input_stream *is)
{
	struct ffmpeg_stream stream = {
		.url = "mpd://X", /* only the mpd:// prefix matters */
		.decoder = NULL,
		.input = is,
	};

	if (is->uri != NULL)
		append_uri_suffix(&stream, is->uri);

	AVFormatContext *f;
	if (av_open_input_file(&f, stream.url, NULL, 0, NULL) != 0)
		return NULL;

	if (av_find_stream_info(f) < 0) {
		av_close_input_file(f);
		return NULL;
	}

	struct tag *tag = tag_new();

	tag->time = f->duration != (int64_t)AV_NOPTS_VALUE
		? f->duration / AV_TIME_BASE
		: 0;

#if LIBAVFORMAT_VERSION_INT >= ((52<<16)+(31<<8)+0)
	av_metadata_conv(f, NULL, f->iformat->metadata_conv);

	ffmpeg_copy_metadata(tag, f->metadata, TAG_TITLE, "title");
#if LIBAVFORMAT_VERSION_INT >= ((52<<16)+(50<<8))
	ffmpeg_copy_metadata(tag, f->metadata, TAG_ARTIST, "artist");
	ffmpeg_copy_metadata(tag, f->metadata, TAG_DATE,   "date");
#else
	ffmpeg_copy_metadata(tag, f->metadata, TAG_ARTIST, "author");
	ffmpeg_copy_metadata(tag, f->metadata, TAG_DATE,   "year");
#endif
	ffmpeg_copy_metadata(tag, f->metadata, TAG_ALBUM, "album");
	ffmpeg_copy_metadata(tag, f->metadata, TAG_COMMENT, "comment");
	ffmpeg_copy_metadata(tag, f->metadata, TAG_GENRE, "genre");
	ffmpeg_copy_metadata(tag, f->metadata, TAG_TRACK, "track");
	ffmpeg_copy_metadata(tag, f->metadata, TAG_ARTIST_SORT, "author-sort");
	ffmpeg_copy_metadata(tag, f->metadata, TAG_ALBUM_ARTIST, "album_artist");
	ffmpeg_copy_metadata(tag, f->metadata, TAG_ALBUM_ARTIST_SORT, "album_artist-sort");
	ffmpeg_copy_metadata(tag, f->metadata, TAG_COMPOSER, "composer");
	ffmpeg_copy_metadata(tag, f->metadata, TAG_PERFORMER, "performer");
	ffmpeg_copy_metadata(tag, f->metadata, TAG_DISC, "disc");
#else
	if (f->author[0])
		tag_add_item(tag, TAG_ARTIST, f->author);
	if (f->title[0])
		tag_add_item(tag, TAG_TITLE, f->title);
	if (f->album[0])
		tag_add_item(tag, TAG_ALBUM, f->album);

	if (f->track > 0) {
		char buffer[16];
		snprintf(buffer, sizeof(buffer), "%d", f->track);
		tag_add_item(tag, TAG_TRACK, buffer);
	}

	if (f->comment[0])
		tag_add_item(tag, TAG_COMMENT, f->comment);
	if (f->genre[0])
		tag_add_item(tag, TAG_GENRE, f->genre);
	if (f->year > 0) {
		char buffer[16];
		snprintf(buffer, sizeof(buffer), "%d", f->year);
		tag_add_item(tag, TAG_DATE, buffer);
	}

#endif

	av_close_input_file(f);

	return tag;
}

/**
 * A list of extensions found for the formats supported by ffmpeg.
 * This list is current as of 02-23-09; To find out if there are more
 * supported formats, check the ffmpeg changelog since this date for
 * more formats.
 */
static const char *const ffmpeg_suffixes[] = {
	"16sv", "3g2", "3gp", "4xm", "8svx", "aa3", "aac", "ac3", "afc", "aif",
	"aifc", "aiff", "al", "alaw", "amr", "anim", "apc", "ape", "asf",
	"atrac", "au", "aud", "avi", "avm2", "avs", "bap", "bfi", "c93", "cak",
	"cin", "cmv", "cpk", "daud", "dct", "divx", "dts", "dv", "dvd", "dxa",
	"eac3", "film", "flac", "flc", "fli", "fll", "flx", "flv", "g726",
	"gsm", "gxf", "iss", "m1v", "m2v", "m2t", "m2ts", "m4a", "m4v", "mad",
	"mj2", "mjpeg", "mjpg", "mka", "mkv", "mlp", "mm", "mmf", "mov", "mp+",
	"mp1", "mp2", "mp3", "mp4", "mpc", "mpeg", "mpg", "mpga", "mpp", "mpu",
	"mve", "mvi", "mxf", "nc", "nsv", "nut", "nuv", "oga", "ogm", "ogv",
	"ogx", "oma", "ogg", "omg", "psp", "pva", "qcp", "qt", "r3d", "ra",
	"ram", "rl2", "rm", "rmvb", "roq", "rpl", "rvc", "shn", "smk", "snd",
	"sol", "son", "spx", "str", "swf", "tgi", "tgq", "tgv", "thp", "ts",
	"tsp", "tta", "xa", "xvid", "uv", "uv2", "vb", "vid", "vob", "voc",
	"vp6", "vmd", "wav", "wma", "wmv", "wsaud", "wsvga", "wv", "wve",
	NULL
};

static const char *const ffmpeg_mime_types[] = {
	"application/m4a",
	"application/mp4",
	"application/octet-stream",
	"application/ogg",
	"application/x-ms-wmz",
	"application/x-ms-wmd",
	"application/x-ogg",
	"application/x-shockwave-flash",
	"application/x-shorten",
	"audio/8svx",
	"audio/16sv",
	"audio/aac",
	"audio/ac3",
	"audio/aiff"
	"audio/amr",
	"audio/basic",
	"audio/flac",
	"audio/m4a",
	"audio/mp4",
	"audio/mpeg",
	"audio/musepack",
	"audio/ogg",
	"audio/qcelp",
	"audio/vorbis",
	"audio/vorbis+ogg",
	"audio/x-8svx",
	"audio/x-16sv",
	"audio/x-aac",
	"audio/x-ac3",
	"audio/x-aiff"
	"audio/x-alaw",
	"audio/x-au",
	"audio/x-dca",
	"audio/x-eac3",
	"audio/x-flac",
	"audio/x-gsm",
	"audio/x-mace",
	"audio/x-matroska",
	"audio/x-monkeys-audio",
	"audio/x-mpeg",
	"audio/x-ms-wma",
	"audio/x-ms-wax",
	"audio/x-musepack",
	"audio/x-ogg",
	"audio/x-vorbis",
	"audio/x-vorbis+ogg",
	"audio/x-pn-realaudio",
	"audio/x-pn-multirate-realaudio",
	"audio/x-speex",
	"audio/x-tta"
	"audio/x-voc",
	"audio/x-wav",
	"audio/x-wma",
	"audio/x-wv",
	"video/anim",
	"video/quicktime",
	"video/msvideo",
	"video/ogg",
	"video/theora",
	"video/x-dv",
	"video/x-flv",
	"video/x-matroska",
	"video/x-mjpeg",
	"video/x-mpeg",
	"video/x-ms-asf",
	"video/x-msvideo",
	"video/x-ms-wmv",
	"video/x-ms-wvx",
	"video/x-ms-wm",
	"video/x-ms-wmx",
	"video/x-nut",
	"video/x-pva",
	"video/x-theora",
	"video/x-vid",
	"video/x-wmv",
	"video/x-xvid",
	NULL
};

const struct decoder_plugin ffmpeg_decoder_plugin = {
	.name = "ffmpeg",
	.init = ffmpeg_init,
	.stream_decode = ffmpeg_decode,
	.stream_tag = ffmpeg_stream_tag,
	.suffixes = ffmpeg_suffixes,
	.mime_types = ffmpeg_mime_types
};