1/*
2 * Copyright (C) 2005  Michael Ahlberg, Måns Rullgård
3 *
4 * Permission is hereby granted, free of charge, to any person
5 * obtaining a copy of this software and associated documentation
6 * files (the "Software"), to deal in the Software without
7 * restriction, including without limitation the rights to use, copy,
8 * modify, merge, publish, distribute, sublicense, and/or sell copies
9 * of the Software, and to permit persons to whom the Software is
10 * furnished to do so, subject to the following conditions:
11 *
12 *  The above copyright notice and this permission notice shall be
13 *  included in all copies or substantial portions of the Software.
14 *
15 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
19 *  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
20 *  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22 *  DEALINGS IN THE SOFTWARE.
23 */
24
25#include <stdlib.h>
26
27#include "libavutil/avstring.h"
28#include "libavutil/base64.h"
29#include "libavutil/dict.h"
30
31#include "libavcodec/bytestream.h"
32#include "libavcodec/vorbis_parser.h"
33
34#include "avformat.h"
35#include "demux.h"
36#include "flac_picture.h"
37#include "internal.h"
38#include "oggdec.h"
39#include "vorbiscomment.h"
40#include "replaygain.h"
41
42static int ogm_chapter(AVFormatContext *as, const uint8_t *key, const uint8_t *val)
43{
44    int i, cnum, h, m, s, ms, keylen = strlen(key);
45    AVChapter *chapter = NULL;
46
47    if (keylen < 9 || av_strncasecmp(key, "CHAPTER", 7) || sscanf(key+7, "%03d", &cnum) != 1)
48        return 0;
49
50    if (keylen <= 10) {
51        if (sscanf(val, "%02d:%02d:%02d.%03d", &h, &m, &s, &ms) < 4)
52            return 0;
53
54        avpriv_new_chapter(as, cnum, (AVRational) { 1, 1000 },
55                           ms + 1000 * (s + 60 * (m + 60 * h)),
56                           AV_NOPTS_VALUE, NULL);
57    } else if (!av_strcasecmp(key + keylen - 4, "NAME")) {
58        for (i = 0; i < as->nb_chapters; i++)
59            if (as->chapters[i]->id == cnum) {
60                chapter = as->chapters[i];
61                break;
62            }
63        if (!chapter)
64            return 0;
65
66        av_dict_set(&chapter->metadata, "title", val, 0);
67    } else
68        return 0;
69
70    return 1;
71}
72
73int ff_vorbis_stream_comment(AVFormatContext *as, AVStream *st,
74                             const uint8_t *buf, int size)
75{
76    int updates = ff_vorbis_comment(as, &st->metadata, buf, size, 1);
77
78    if (updates > 0) {
79        st->event_flags |= AVSTREAM_EVENT_FLAG_METADATA_UPDATED;
80    }
81
82    return updates;
83}
84
85/**
86 * This function temporarily modifies the (const qualified) input buffer
87 * and reverts its changes before return. The input buffer needs to have
88 * at least one byte of padding.
89 */
90static int vorbis_parse_single_comment(AVFormatContext *as, AVDictionary **m,
91                                       const uint8_t *buf, uint32_t size,
92                                       int *updates, int parse_picture)
93{
94    char *t = (char*)buf, *v = memchr(t, '=', size);
95    int tl, vl;
96    char backup;
97
98    if (!v)
99        return 0;
100
101    tl = v - t;
102    vl = size - tl - 1;
103    v++;
104
105    if (!tl || !vl)
106        return 0;
107
108    t[tl]  = 0;
109
110    backup = v[vl];
111    v[vl]  = 0;
112
113    /* The format in which the pictures are stored is the FLAC format.
114     * Xiph says: "The binary FLAC picture structure is base64 encoded
115     * and placed within a VorbisComment with the tag name
116     * 'METADATA_BLOCK_PICTURE'. This is the preferred and
117     * recommended way of embedding cover art within VorbisComments."
118     */
119    if (!av_strcasecmp(t, "METADATA_BLOCK_PICTURE") && parse_picture) {
120        int ret, len = AV_BASE64_DECODE_SIZE(vl);
121        uint8_t *pict = av_malloc(len + AV_INPUT_BUFFER_PADDING_SIZE);
122
123        if (!pict) {
124            av_log(as, AV_LOG_WARNING, "out-of-memory error. Skipping cover art block.\n");
125            goto end;
126        }
127        ret = av_base64_decode(pict, v, len);
128        if (ret > 0)
129            ret = ff_flac_parse_picture(as, &pict, ret, 0);
130        av_freep(&pict);
131        if (ret < 0) {
132            av_log(as, AV_LOG_WARNING, "Failed to parse cover art block.\n");
133            goto end;
134        }
135    } else if (!ogm_chapter(as, t, v)) {
136        (*updates)++;
137        if (av_dict_get(*m, t, NULL, 0))
138            av_dict_set(m, t, ";", AV_DICT_APPEND);
139        av_dict_set(m, t, v, AV_DICT_APPEND);
140    }
141end:
142    t[tl] = '=';
143    v[vl] = backup;
144
145    return 0;
146}
147
148int ff_vorbis_comment(AVFormatContext *as, AVDictionary **m,
149                      const uint8_t *buf, int size,
150                      int parse_picture)
151{
152    const uint8_t *p   = buf;
153    const uint8_t *end = buf + size;
154    int updates        = 0;
155    unsigned n;
156    int s, ret;
157
158    /* must have vendor_length and user_comment_list_length */
159    if (size < 8)
160        return AVERROR_INVALIDDATA;
161
162    s = bytestream_get_le32(&p);
163
164    if (end - p - 4 < s || s < 0)
165        return AVERROR_INVALIDDATA;
166
167    p += s;
168
169    n = bytestream_get_le32(&p);
170
171    while (end - p >= 4 && n > 0) {
172        s = bytestream_get_le32(&p);
173
174        if (end - p < s || s < 0)
175            break;
176
177        ret = vorbis_parse_single_comment(as, m, p, s, &updates, parse_picture);
178        if (ret < 0)
179            return ret;
180        p += s;
181        n--;
182    }
183
184    if (p != end)
185        av_log(as, AV_LOG_INFO,
186               "%"PTRDIFF_SPECIFIER" bytes of comment header remain\n", end - p);
187    if (n > 0)
188        av_log(as, AV_LOG_INFO,
189               "truncated comment header, %i comments not found\n", n);
190
191    ff_metadata_conv(m, NULL, ff_vorbiscomment_metadata_conv);
192
193    return updates;
194}
195
196/*
197 * Parse the vorbis header
198 *
199 * Vorbis Identification header from Vorbis_I_spec.html#vorbis-spec-codec
200 * [vorbis_version] = read 32 bits as unsigned integer | Not used
201 * [audio_channels] = read 8 bit integer as unsigned | Used
202 * [audio_sample_rate] = read 32 bits as unsigned integer | Used
203 * [bitrate_maximum] = read 32 bits as signed integer | Not used yet
204 * [bitrate_nominal] = read 32 bits as signed integer | Not used yet
205 * [bitrate_minimum] = read 32 bits as signed integer | Used as bitrate
206 * [blocksize_0] = read 4 bits as unsigned integer | Not Used
207 * [blocksize_1] = read 4 bits as unsigned integer | Not Used
208 * [framing_flag] = read one bit | Not Used
209 */
210
211struct oggvorbis_private {
212    unsigned int len[3];
213    unsigned char *packet[3];
214    AVVorbisParseContext *vp;
215    int64_t final_pts;
216    int final_duration;
217};
218
219static int fixup_vorbis_headers(AVFormatContext *as,
220                                struct oggvorbis_private *priv,
221                                uint8_t **buf)
222{
223    int i, offset, len, err;
224    int buf_len;
225    unsigned char *ptr;
226
227    len = priv->len[0] + priv->len[1] + priv->len[2];
228    buf_len = len + len / 255 + 64;
229
230    if (*buf)
231        return AVERROR_INVALIDDATA;
232
233    ptr = *buf = av_realloc(NULL, buf_len);
234    if (!ptr)
235        return AVERROR(ENOMEM);
236    memset(*buf, '\0', buf_len);
237
238    ptr[0]  = 2;
239    offset  = 1;
240    offset += av_xiphlacing(&ptr[offset], priv->len[0]);
241    offset += av_xiphlacing(&ptr[offset], priv->len[1]);
242    for (i = 0; i < 3; i++) {
243        memcpy(&ptr[offset], priv->packet[i], priv->len[i]);
244        offset += priv->len[i];
245        av_freep(&priv->packet[i]);
246    }
247    if ((err = av_reallocp(buf, offset + AV_INPUT_BUFFER_PADDING_SIZE)) < 0)
248        return err;
249    return offset;
250}
251
252static void vorbis_cleanup(AVFormatContext *s, int idx)
253{
254    struct ogg *ogg = s->priv_data;
255    struct ogg_stream *os = ogg->streams + idx;
256    struct oggvorbis_private *priv = os->private;
257    int i;
258    if (os->private) {
259        av_vorbis_parse_free(&priv->vp);
260        for (i = 0; i < 3; i++)
261            av_freep(&priv->packet[i]);
262    }
263}
264
265static int vorbis_update_metadata(AVFormatContext *s, int idx)
266{
267    struct ogg *ogg = s->priv_data;
268    struct ogg_stream *os = ogg->streams + idx;
269    AVStream *st = s->streams[idx];
270    int ret;
271
272    if (os->psize <= 8)
273        return 0;
274
275    /* New metadata packet; release old data. */
276    av_dict_free(&st->metadata);
277    ret = ff_vorbis_stream_comment(s, st, os->buf + os->pstart + 7,
278                                   os->psize - 8);
279    if (ret < 0)
280        return ret;
281
282    /* Update the metadata if possible. */
283    av_freep(&os->new_metadata);
284    if (st->metadata) {
285        os->new_metadata = av_packet_pack_dictionary(st->metadata, &os->new_metadata_size);
286    /* Send an empty dictionary to indicate that metadata has been cleared. */
287    } else {
288        os->new_metadata = av_mallocz(1);
289        os->new_metadata_size = 0;
290    }
291
292    return ret;
293}
294
295static int vorbis_header(AVFormatContext *s, int idx)
296{
297    struct ogg *ogg = s->priv_data;
298    AVStream *st    = s->streams[idx];
299    struct ogg_stream *os = ogg->streams + idx;
300    struct oggvorbis_private *priv;
301    int pkt_type = os->buf[os->pstart];
302
303    if (!os->private) {
304        os->private = av_mallocz(sizeof(struct oggvorbis_private));
305        if (!os->private)
306            return AVERROR(ENOMEM);
307    }
308
309    priv = os->private;
310
311    if (!(pkt_type & 1))
312        return priv->vp ? 0 : AVERROR_INVALIDDATA;
313
314    if (os->psize < 1 || pkt_type > 5)
315        return AVERROR_INVALIDDATA;
316
317    if (priv->packet[pkt_type >> 1])
318        return AVERROR_INVALIDDATA;
319    if (pkt_type > 1 && !priv->packet[0] || pkt_type > 3 && !priv->packet[1])
320        return priv->vp ? 0 : AVERROR_INVALIDDATA;
321
322    priv->len[pkt_type >> 1]    = os->psize;
323    priv->packet[pkt_type >> 1] = av_memdup(os->buf + os->pstart, os->psize);
324    if (!priv->packet[pkt_type >> 1])
325        return AVERROR(ENOMEM);
326    if (os->buf[os->pstart] == 1) {
327        const uint8_t *p = os->buf + os->pstart + 7; /* skip "\001vorbis" tag */
328        unsigned blocksize, bs0, bs1;
329        int srate;
330        int channels;
331
332        if (os->psize != 30)
333            return AVERROR_INVALIDDATA;
334
335        if (bytestream_get_le32(&p) != 0) /* vorbis_version */
336            return AVERROR_INVALIDDATA;
337
338        channels = bytestream_get_byte(&p);
339        if (st->codecpar->ch_layout.nb_channels &&
340            channels != st->codecpar->ch_layout.nb_channels) {
341            av_log(s, AV_LOG_ERROR, "Channel change is not supported\n");
342            return AVERROR_PATCHWELCOME;
343        }
344        st->codecpar->ch_layout.nb_channels = channels;
345        srate               = bytestream_get_le32(&p);
346        p += 4; // skip maximum bitrate
347        st->codecpar->bit_rate = bytestream_get_le32(&p); // nominal bitrate
348        p += 4; // skip minimum bitrate
349
350        blocksize = bytestream_get_byte(&p);
351        bs0       = blocksize & 15;
352        bs1       = blocksize >> 4;
353
354        if (bs0 > bs1)
355            return AVERROR_INVALIDDATA;
356        if (bs0 < 6 || bs1 > 13)
357            return AVERROR_INVALIDDATA;
358
359        if (bytestream_get_byte(&p) != 1) /* framing_flag */
360            return AVERROR_INVALIDDATA;
361
362        st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
363        st->codecpar->codec_id   = AV_CODEC_ID_VORBIS;
364
365        if (srate > 0) {
366            st->codecpar->sample_rate = srate;
367            avpriv_set_pts_info(st, 64, 1, srate);
368        }
369    } else if (os->buf[os->pstart] == 3) {
370        if (vorbis_update_metadata(s, idx) >= 0 && priv->len[1] > 10) {
371            unsigned new_len;
372
373            int ret = ff_replaygain_export(st, st->metadata);
374            if (ret < 0)
375                return ret;
376
377            // drop all metadata we parsed and which is not required by libvorbis
378            new_len = 7 + 4 + AV_RL32(priv->packet[1] + 7) + 4 + 1;
379            if (new_len >= 16 && new_len < os->psize) {
380                AV_WL32(priv->packet[1] + new_len - 5, 0);
381                priv->packet[1][new_len - 1] = 1;
382                priv->len[1]                 = new_len;
383            }
384        }
385    } else {
386        int ret;
387
388        if (priv->vp)
389             return AVERROR_INVALIDDATA;
390
391        ret = fixup_vorbis_headers(s, priv, &st->codecpar->extradata);
392        if (ret < 0) {
393            st->codecpar->extradata_size = 0;
394            return ret;
395        }
396        st->codecpar->extradata_size = ret;
397
398        priv->vp = av_vorbis_parse_init(st->codecpar->extradata, st->codecpar->extradata_size);
399        if (!priv->vp) {
400            av_freep(&st->codecpar->extradata);
401            st->codecpar->extradata_size = 0;
402            return AVERROR_UNKNOWN;
403        }
404    }
405
406    return 1;
407}
408
409static int vorbis_packet(AVFormatContext *s, int idx)
410{
411    struct ogg *ogg = s->priv_data;
412    struct ogg_stream *os = ogg->streams + idx;
413    struct oggvorbis_private *priv = os->private;
414    int duration, flags = 0;
415
416    if (!priv->vp)
417        return AVERROR_INVALIDDATA;
418
419    /* first packet handling
420     * here we parse the duration of each packet in the first page and compare
421     * the total duration to the page granule to find the encoder delay and
422     * set the first timestamp */
423    if ((!os->lastpts || os->lastpts == AV_NOPTS_VALUE) && !(os->flags & OGG_FLAG_EOS) && (int64_t)os->granule>=0) {
424        int seg, d;
425        uint8_t *last_pkt  = os->buf + os->pstart;
426        uint8_t *next_pkt  = last_pkt;
427
428        av_vorbis_parse_reset(priv->vp);
429        duration = 0;
430        seg = os->segp;
431        d = av_vorbis_parse_frame_flags(priv->vp, last_pkt, 1, &flags);
432        if (d < 0) {
433            os->pflags |= AV_PKT_FLAG_CORRUPT;
434            return 0;
435        } else if (flags & VORBIS_FLAG_COMMENT) {
436            vorbis_update_metadata(s, idx);
437            flags = 0;
438        }
439        duration += d;
440        last_pkt = next_pkt =  next_pkt + os->psize;
441        for (; seg < os->nsegs; seg++) {
442            if (os->segments[seg] < 255) {
443                int d = av_vorbis_parse_frame_flags(priv->vp, last_pkt, 1, &flags);
444                if (d < 0) {
445                    duration = os->granule;
446                    break;
447                } else if (flags & VORBIS_FLAG_COMMENT) {
448                    vorbis_update_metadata(s, idx);
449                    flags = 0;
450                }
451                duration += d;
452                last_pkt  = next_pkt + os->segments[seg];
453            }
454            next_pkt += os->segments[seg];
455        }
456        os->lastpts                 =
457        os->lastdts                 = os->granule - duration;
458
459        if (!os->granule && duration) //hack to deal with broken files (Ticket3710)
460            os->lastpts = os->lastdts = AV_NOPTS_VALUE;
461
462        if (s->streams[idx]->start_time == AV_NOPTS_VALUE) {
463            s->streams[idx]->start_time = FFMAX(os->lastpts, 0);
464            if (s->streams[idx]->duration != AV_NOPTS_VALUE)
465                s->streams[idx]->duration -= s->streams[idx]->start_time;
466        }
467        priv->final_pts          = AV_NOPTS_VALUE;
468        av_vorbis_parse_reset(priv->vp);
469    }
470
471    /* parse packet duration */
472    if (os->psize > 0) {
473        duration = av_vorbis_parse_frame_flags(priv->vp, os->buf + os->pstart, 1, &flags);
474        if (duration < 0) {
475            os->pflags |= AV_PKT_FLAG_CORRUPT;
476            return 0;
477        } else if (flags & VORBIS_FLAG_COMMENT) {
478            vorbis_update_metadata(s, idx);
479            flags = 0;
480        }
481        os->pduration = duration;
482    }
483
484    /* final packet handling
485     * here we save the pts of the first packet in the final page, sum up all
486     * packet durations in the final page except for the last one, and compare
487     * to the page granule to find the duration of the final packet */
488    if (os->flags & OGG_FLAG_EOS) {
489        if (os->lastpts != AV_NOPTS_VALUE) {
490            priv->final_pts      = os->lastpts;
491            priv->final_duration = 0;
492        }
493        if (os->segp == os->nsegs) {
494            int64_t skip = priv->final_pts + priv->final_duration + os->pduration - os->granule;
495            if (skip > 0)
496                os->end_trimming = skip;
497            os->pduration = os->granule - priv->final_pts - priv->final_duration;
498        }
499        priv->final_duration += os->pduration;
500    }
501
502    return 0;
503}
504
505const struct ogg_codec ff_vorbis_codec = {
506    .magic     = "\001vorbis",
507    .magicsize = 7,
508    .header    = vorbis_header,
509    .packet    = vorbis_packet,
510    .cleanup   = vorbis_cleanup,
511    .nb_header = 3,
512};
513