1/*
2 * Monkey's Audio APE demuxer
3 * Copyright (c) 2007 Benjamin Zores <ben@geexbox.org>
4 *  based upon libdemac from Dave Chapman.
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23#include <stdio.h>
24
25#include "libavutil/intreadwrite.h"
26#include "avformat.h"
27
28#define ENABLE_DEBUG 0
29
30/* The earliest and latest file formats supported by this library */
31#define APE_MIN_VERSION 3950
32#define APE_MAX_VERSION 3990
33
34#define MAC_FORMAT_FLAG_8_BIT                 1 // is 8-bit [OBSOLETE]
35#define MAC_FORMAT_FLAG_CRC                   2 // uses the new CRC32 error detection [OBSOLETE]
36#define MAC_FORMAT_FLAG_HAS_PEAK_LEVEL        4 // uint32 nPeakLevel after the header [OBSOLETE]
37#define MAC_FORMAT_FLAG_24_BIT                8 // is 24-bit [OBSOLETE]
38#define MAC_FORMAT_FLAG_HAS_SEEK_ELEMENTS    16 // has the number of seek elements after the peak level
39#define MAC_FORMAT_FLAG_CREATE_WAV_HEADER    32 // create the wave header on decompression (not stored)
40
41#define MAC_SUBFRAME_SIZE 4608
42
43#define APE_EXTRADATA_SIZE 6
44
45/* APE tags */
46#define APE_TAG_VERSION               2000
47#define APE_TAG_FOOTER_BYTES          32
48#define APE_TAG_FLAG_CONTAINS_HEADER  (1 << 31)
49#define APE_TAG_FLAG_IS_HEADER        (1 << 29)
50
51typedef struct {
52    int64_t pos;
53    int nblocks;
54    int size;
55    int skip;
56    int64_t pts;
57} APEFrame;
58
59typedef struct {
60    /* Derived fields */
61    uint32_t junklength;
62    uint32_t firstframe;
63    uint32_t totalsamples;
64    int currentframe;
65    APEFrame *frames;
66
67    /* Info from Descriptor Block */
68    char magic[4];
69    int16_t fileversion;
70    int16_t padding1;
71    uint32_t descriptorlength;
72    uint32_t headerlength;
73    uint32_t seektablelength;
74    uint32_t wavheaderlength;
75    uint32_t audiodatalength;
76    uint32_t audiodatalength_high;
77    uint32_t wavtaillength;
78    uint8_t md5[16];
79
80    /* Info from Header Block */
81    uint16_t compressiontype;
82    uint16_t formatflags;
83    uint32_t blocksperframe;
84    uint32_t finalframeblocks;
85    uint32_t totalframes;
86    uint16_t bps;
87    uint16_t channels;
88    uint32_t samplerate;
89
90    /* Seektable */
91    uint32_t *seektable;
92} APEContext;
93
94static void ape_tag_read_field(AVFormatContext *s)
95{
96    ByteIOContext *pb = s->pb;
97    uint8_t key[1024], value[1024];
98    uint32_t size;
99    int i, l;
100
101    size = get_le32(pb);  /* field size */
102    url_fskip(pb, 4);     /* skip field flags */
103
104    for (i=0; pb->buf_ptr[i]!='0' && pb->buf_ptr[i]>=0x20 && pb->buf_ptr[i]<=0x7E; i++);
105
106    l = FFMIN(i,    sizeof(key) -1);
107    get_buffer(pb, key,  l);
108    key[l]  = 0;
109    url_fskip(pb, 1 + i-l);
110    l = FFMIN(size, sizeof(value)-1);
111    get_buffer(pb, value, l);
112    value[l] = 0;
113    url_fskip(pb, size-l);
114    if (l < size)
115        av_log(s, AV_LOG_WARNING, "Too long '%s' tag was truncated.\n", key);
116    av_metadata_set(&s->metadata, key, value);
117}
118
119static void ape_parse_tag(AVFormatContext *s)
120{
121    ByteIOContext *pb = s->pb;
122    int file_size = url_fsize(pb);
123    uint32_t val, fields, tag_bytes;
124    uint8_t buf[8];
125    int i;
126
127    if (file_size < APE_TAG_FOOTER_BYTES)
128        return;
129
130    url_fseek(pb, file_size - APE_TAG_FOOTER_BYTES, SEEK_SET);
131
132    get_buffer(pb, buf, 8);    /* APETAGEX */
133    if (strncmp(buf, "APETAGEX", 8)) {
134        return;
135    }
136
137    val = get_le32(pb);        /* APE tag version */
138    if (val > APE_TAG_VERSION) {
139        av_log(s, AV_LOG_ERROR, "Unsupported tag version. (>=%d)\n", APE_TAG_VERSION);
140        return;
141    }
142
143    tag_bytes = get_le32(pb);  /* tag size */
144    if (tag_bytes - APE_TAG_FOOTER_BYTES > (1024 * 1024 * 16)) {
145        av_log(s, AV_LOG_ERROR, "Tag size is way too big\n");
146        return;
147    }
148
149    fields = get_le32(pb);     /* number of fields */
150    if (fields > 65536) {
151        av_log(s, AV_LOG_ERROR, "Too many tag fields (%d)\n", fields);
152        return;
153    }
154
155    val = get_le32(pb);        /* flags */
156    if (val & APE_TAG_FLAG_IS_HEADER) {
157        av_log(s, AV_LOG_ERROR, "APE Tag is a header\n");
158        return;
159    }
160
161    if (val & APE_TAG_FLAG_CONTAINS_HEADER)
162        tag_bytes += 2*APE_TAG_FOOTER_BYTES;
163
164    url_fseek(pb, file_size - tag_bytes, SEEK_SET);
165
166    for (i=0; i<fields; i++)
167        ape_tag_read_field(s);
168
169#if ENABLE_DEBUG
170    av_log(s, AV_LOG_DEBUG, "\nAPE Tags:\n\n");
171    av_log(s, AV_LOG_DEBUG, "title     = %s\n", s->title);
172    av_log(s, AV_LOG_DEBUG, "author    = %s\n", s->author);
173    av_log(s, AV_LOG_DEBUG, "copyright = %s\n", s->copyright);
174    av_log(s, AV_LOG_DEBUG, "comment   = %s\n", s->comment);
175    av_log(s, AV_LOG_DEBUG, "album     = %s\n", s->album);
176    av_log(s, AV_LOG_DEBUG, "year      = %d\n", s->year);
177    av_log(s, AV_LOG_DEBUG, "track     = %d\n", s->track);
178    av_log(s, AV_LOG_DEBUG, "genre     = %s\n", s->genre);
179#endif
180}
181
182static int ape_probe(AVProbeData * p)
183{
184    if (p->buf[0] == 'M' && p->buf[1] == 'A' && p->buf[2] == 'C' && p->buf[3] == ' ')
185        return AVPROBE_SCORE_MAX;
186
187    return 0;
188}
189
190static void ape_dumpinfo(AVFormatContext * s, APEContext * ape_ctx)
191{
192#if ENABLE_DEBUG
193    int i;
194
195    av_log(s, AV_LOG_DEBUG, "Descriptor Block:\n\n");
196    av_log(s, AV_LOG_DEBUG, "magic                = \"%c%c%c%c\"\n", ape_ctx->magic[0], ape_ctx->magic[1], ape_ctx->magic[2], ape_ctx->magic[3]);
197    av_log(s, AV_LOG_DEBUG, "fileversion          = %d\n", ape_ctx->fileversion);
198    av_log(s, AV_LOG_DEBUG, "descriptorlength     = %d\n", ape_ctx->descriptorlength);
199    av_log(s, AV_LOG_DEBUG, "headerlength         = %d\n", ape_ctx->headerlength);
200    av_log(s, AV_LOG_DEBUG, "seektablelength      = %d\n", ape_ctx->seektablelength);
201    av_log(s, AV_LOG_DEBUG, "wavheaderlength      = %d\n", ape_ctx->wavheaderlength);
202    av_log(s, AV_LOG_DEBUG, "audiodatalength      = %d\n", ape_ctx->audiodatalength);
203    av_log(s, AV_LOG_DEBUG, "audiodatalength_high = %d\n", ape_ctx->audiodatalength_high);
204    av_log(s, AV_LOG_DEBUG, "wavtaillength        = %d\n", ape_ctx->wavtaillength);
205    av_log(s, AV_LOG_DEBUG, "md5                  = ");
206    for (i = 0; i < 16; i++)
207         av_log(s, AV_LOG_DEBUG, "%02x", ape_ctx->md5[i]);
208    av_log(s, AV_LOG_DEBUG, "\n");
209
210    av_log(s, AV_LOG_DEBUG, "\nHeader Block:\n\n");
211
212    av_log(s, AV_LOG_DEBUG, "compressiontype      = %d\n", ape_ctx->compressiontype);
213    av_log(s, AV_LOG_DEBUG, "formatflags          = %d\n", ape_ctx->formatflags);
214    av_log(s, AV_LOG_DEBUG, "blocksperframe       = %d\n", ape_ctx->blocksperframe);
215    av_log(s, AV_LOG_DEBUG, "finalframeblocks     = %d\n", ape_ctx->finalframeblocks);
216    av_log(s, AV_LOG_DEBUG, "totalframes          = %d\n", ape_ctx->totalframes);
217    av_log(s, AV_LOG_DEBUG, "bps                  = %d\n", ape_ctx->bps);
218    av_log(s, AV_LOG_DEBUG, "channels             = %d\n", ape_ctx->channels);
219    av_log(s, AV_LOG_DEBUG, "samplerate           = %d\n", ape_ctx->samplerate);
220
221    av_log(s, AV_LOG_DEBUG, "\nSeektable\n\n");
222    if ((ape_ctx->seektablelength / sizeof(uint32_t)) != ape_ctx->totalframes) {
223        av_log(s, AV_LOG_DEBUG, "No seektable\n");
224    } else {
225        for (i = 0; i < ape_ctx->seektablelength / sizeof(uint32_t); i++) {
226            if (i < ape_ctx->totalframes - 1) {
227                av_log(s, AV_LOG_DEBUG, "%8d   %d (%d bytes)\n", i, ape_ctx->seektable[i], ape_ctx->seektable[i + 1] - ape_ctx->seektable[i]);
228            } else {
229                av_log(s, AV_LOG_DEBUG, "%8d   %d\n", i, ape_ctx->seektable[i]);
230            }
231        }
232    }
233
234    av_log(s, AV_LOG_DEBUG, "\nFrames\n\n");
235    for (i = 0; i < ape_ctx->totalframes; i++)
236        av_log(s, AV_LOG_DEBUG, "%8d   %8lld %8d (%d samples)\n", i, ape_ctx->frames[i].pos, ape_ctx->frames[i].size, ape_ctx->frames[i].nblocks);
237
238    av_log(s, AV_LOG_DEBUG, "\nCalculated information:\n\n");
239    av_log(s, AV_LOG_DEBUG, "junklength           = %d\n", ape_ctx->junklength);
240    av_log(s, AV_LOG_DEBUG, "firstframe           = %d\n", ape_ctx->firstframe);
241    av_log(s, AV_LOG_DEBUG, "totalsamples         = %d\n", ape_ctx->totalsamples);
242#endif
243}
244
245static int ape_read_header(AVFormatContext * s, AVFormatParameters * ap)
246{
247    ByteIOContext *pb = s->pb;
248    APEContext *ape = s->priv_data;
249    AVStream *st;
250    uint32_t tag;
251    int i;
252    int total_blocks;
253    int64_t pts;
254
255    /* TODO: Skip any leading junk such as id3v2 tags */
256    ape->junklength = 0;
257
258    tag = get_le32(pb);
259    if (tag != MKTAG('M', 'A', 'C', ' '))
260        return -1;
261
262    ape->fileversion = get_le16(pb);
263
264    if (ape->fileversion < APE_MIN_VERSION || ape->fileversion > APE_MAX_VERSION) {
265        av_log(s, AV_LOG_ERROR, "Unsupported file version - %d.%02d\n", ape->fileversion / 1000, (ape->fileversion % 1000) / 10);
266        return -1;
267    }
268
269    if (ape->fileversion >= 3980) {
270        ape->padding1             = get_le16(pb);
271        ape->descriptorlength     = get_le32(pb);
272        ape->headerlength         = get_le32(pb);
273        ape->seektablelength      = get_le32(pb);
274        ape->wavheaderlength      = get_le32(pb);
275        ape->audiodatalength      = get_le32(pb);
276        ape->audiodatalength_high = get_le32(pb);
277        ape->wavtaillength        = get_le32(pb);
278        get_buffer(pb, ape->md5, 16);
279
280        /* Skip any unknown bytes at the end of the descriptor.
281           This is for future compatibility */
282        if (ape->descriptorlength > 52)
283            url_fseek(pb, ape->descriptorlength - 52, SEEK_CUR);
284
285        /* Read header data */
286        ape->compressiontype      = get_le16(pb);
287        ape->formatflags          = get_le16(pb);
288        ape->blocksperframe       = get_le32(pb);
289        ape->finalframeblocks     = get_le32(pb);
290        ape->totalframes          = get_le32(pb);
291        ape->bps                  = get_le16(pb);
292        ape->channels             = get_le16(pb);
293        ape->samplerate           = get_le32(pb);
294    } else {
295        ape->descriptorlength = 0;
296        ape->headerlength = 32;
297
298        ape->compressiontype      = get_le16(pb);
299        ape->formatflags          = get_le16(pb);
300        ape->channels             = get_le16(pb);
301        ape->samplerate           = get_le32(pb);
302        ape->wavheaderlength      = get_le32(pb);
303        ape->wavtaillength        = get_le32(pb);
304        ape->totalframes          = get_le32(pb);
305        ape->finalframeblocks     = get_le32(pb);
306
307        if (ape->formatflags & MAC_FORMAT_FLAG_HAS_PEAK_LEVEL) {
308            url_fseek(pb, 4, SEEK_CUR); /* Skip the peak level */
309            ape->headerlength += 4;
310        }
311
312        if (ape->formatflags & MAC_FORMAT_FLAG_HAS_SEEK_ELEMENTS) {
313            ape->seektablelength = get_le32(pb);
314            ape->headerlength += 4;
315            ape->seektablelength *= sizeof(int32_t);
316        } else
317            ape->seektablelength = ape->totalframes * sizeof(int32_t);
318
319        if (ape->formatflags & MAC_FORMAT_FLAG_8_BIT)
320            ape->bps = 8;
321        else if (ape->formatflags & MAC_FORMAT_FLAG_24_BIT)
322            ape->bps = 24;
323        else
324            ape->bps = 16;
325
326        if (ape->fileversion >= 3950)
327            ape->blocksperframe = 73728 * 4;
328        else if (ape->fileversion >= 3900 || (ape->fileversion >= 3800  && ape->compressiontype >= 4000))
329            ape->blocksperframe = 73728;
330        else
331            ape->blocksperframe = 9216;
332
333        /* Skip any stored wav header */
334        if (!(ape->formatflags & MAC_FORMAT_FLAG_CREATE_WAV_HEADER))
335            url_fskip(pb, ape->wavheaderlength);
336    }
337
338    if(ape->totalframes > UINT_MAX / sizeof(APEFrame)){
339        av_log(s, AV_LOG_ERROR, "Too many frames: %d\n", ape->totalframes);
340        return -1;
341    }
342    ape->frames       = av_malloc(ape->totalframes * sizeof(APEFrame));
343    if(!ape->frames)
344        return AVERROR_NOMEM;
345    ape->firstframe   = ape->junklength + ape->descriptorlength + ape->headerlength + ape->seektablelength + ape->wavheaderlength;
346    ape->currentframe = 0;
347
348
349    ape->totalsamples = ape->finalframeblocks;
350    if (ape->totalframes > 1)
351        ape->totalsamples += ape->blocksperframe * (ape->totalframes - 1);
352
353    if (ape->seektablelength > 0) {
354        ape->seektable = av_malloc(ape->seektablelength);
355        for (i = 0; i < ape->seektablelength / sizeof(uint32_t); i++)
356            ape->seektable[i] = get_le32(pb);
357    }
358
359    ape->frames[0].pos     = ape->firstframe;
360    ape->frames[0].nblocks = ape->blocksperframe;
361    ape->frames[0].skip    = 0;
362    for (i = 1; i < ape->totalframes; i++) {
363        ape->frames[i].pos      = ape->seektable[i]; //ape->frames[i-1].pos + ape->blocksperframe;
364        ape->frames[i].nblocks  = ape->blocksperframe;
365        ape->frames[i - 1].size = ape->frames[i].pos - ape->frames[i - 1].pos;
366        ape->frames[i].skip     = (ape->frames[i].pos - ape->frames[0].pos) & 3;
367    }
368    ape->frames[ape->totalframes - 1].size    = ape->finalframeblocks * 4;
369    ape->frames[ape->totalframes - 1].nblocks = ape->finalframeblocks;
370
371    for (i = 0; i < ape->totalframes; i++) {
372        if(ape->frames[i].skip){
373            ape->frames[i].pos  -= ape->frames[i].skip;
374            ape->frames[i].size += ape->frames[i].skip;
375        }
376        ape->frames[i].size = (ape->frames[i].size + 3) & ~3;
377    }
378
379
380    ape_dumpinfo(s, ape);
381
382    /* try to read APE tags */
383    if (!url_is_streamed(pb)) {
384        ape_parse_tag(s);
385        url_fseek(pb, 0, SEEK_SET);
386    }
387
388    av_log(s, AV_LOG_DEBUG, "Decoding file - v%d.%02d, compression level %d\n", ape->fileversion / 1000, (ape->fileversion % 1000) / 10, ape->compressiontype);
389
390    /* now we are ready: build format streams */
391    st = av_new_stream(s, 0);
392    if (!st)
393        return -1;
394
395    total_blocks = (ape->totalframes == 0) ? 0 : ((ape->totalframes - 1) * ape->blocksperframe) + ape->finalframeblocks;
396
397    st->codec->codec_type      = CODEC_TYPE_AUDIO;
398    st->codec->codec_id        = CODEC_ID_APE;
399    st->codec->codec_tag       = MKTAG('A', 'P', 'E', ' ');
400    st->codec->channels        = ape->channels;
401    st->codec->sample_rate     = ape->samplerate;
402    st->codec->bits_per_coded_sample = ape->bps;
403    st->codec->frame_size      = MAC_SUBFRAME_SIZE;
404
405    st->nb_frames = ape->totalframes;
406    s->start_time = 0;
407    s->duration   = (int64_t) total_blocks * AV_TIME_BASE / ape->samplerate;
408    av_set_pts_info(st, 64, MAC_SUBFRAME_SIZE, ape->samplerate);
409
410    st->codec->extradata = av_malloc(APE_EXTRADATA_SIZE);
411    st->codec->extradata_size = APE_EXTRADATA_SIZE;
412    AV_WL16(st->codec->extradata + 0, ape->fileversion);
413    AV_WL16(st->codec->extradata + 2, ape->compressiontype);
414    AV_WL16(st->codec->extradata + 4, ape->formatflags);
415
416    pts = 0;
417    for (i = 0; i < ape->totalframes; i++) {
418        ape->frames[i].pts = pts;
419        av_add_index_entry(st, ape->frames[i].pos, ape->frames[i].pts, 0, 0, AVINDEX_KEYFRAME);
420        pts += ape->blocksperframe / MAC_SUBFRAME_SIZE;
421    }
422
423    return 0;
424}
425
426static int ape_read_packet(AVFormatContext * s, AVPacket * pkt)
427{
428    int ret;
429    int nblocks;
430    APEContext *ape = s->priv_data;
431    uint32_t extra_size = 8;
432
433    if (url_feof(s->pb))
434        return AVERROR_IO;
435    if (ape->currentframe > ape->totalframes)
436        return AVERROR_IO;
437
438    url_fseek (s->pb, ape->frames[ape->currentframe].pos, SEEK_SET);
439
440    /* Calculate how many blocks there are in this frame */
441    if (ape->currentframe == (ape->totalframes - 1))
442        nblocks = ape->finalframeblocks;
443    else
444        nblocks = ape->blocksperframe;
445
446    if (av_new_packet(pkt,  ape->frames[ape->currentframe].size + extra_size) < 0)
447        return AVERROR_NOMEM;
448
449    AV_WL32(pkt->data    , nblocks);
450    AV_WL32(pkt->data + 4, ape->frames[ape->currentframe].skip);
451    ret = get_buffer(s->pb, pkt->data + extra_size, ape->frames[ape->currentframe].size);
452
453    pkt->pts = ape->frames[ape->currentframe].pts;
454    pkt->stream_index = 0;
455
456    /* note: we need to modify the packet size here to handle the last
457       packet */
458    pkt->size = ret + extra_size;
459
460    ape->currentframe++;
461
462    return 0;
463}
464
465static int ape_read_close(AVFormatContext * s)
466{
467    APEContext *ape = s->priv_data;
468
469    av_freep(&ape->frames);
470    av_freep(&ape->seektable);
471    return 0;
472}
473
474static int ape_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
475{
476    AVStream *st = s->streams[stream_index];
477    APEContext *ape = s->priv_data;
478    int index = av_index_search_timestamp(st, timestamp, flags);
479
480    if (index < 0)
481        return -1;
482
483    ape->currentframe = index;
484    return 0;
485}
486
487AVInputFormat ape_demuxer = {
488    "ape",
489    NULL_IF_CONFIG_SMALL("Monkey's Audio"),
490    sizeof(APEContext),
491    ape_probe,
492    ape_read_header,
493    ape_read_packet,
494    ape_read_close,
495    ape_read_seek,
496    .extensions = "ape,apl,mac"
497};
498