/* * ASF compatible decoder. * Copyright (c) 2000, 2001 Fabrice Bellard. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */#include "avformat.h"#include "avi.h"#include "mpegaudio.h"#include "asf.h"#undef NDEBUG#include <assert.h>#define FRAME_HEADER_SIZE 17// Fix Me! FRAME_HEADER_SIZE may be different.static const GUID index_guid = {    0x33000890, 0xe5b1, 0x11cf, { 0x89, 0xf4, 0x00, 0xa0, 0xc9, 0x03, 0x49, 0xcb },};/**********************************//* decoding *///#define DEBUG#ifdef DEBUG#define PRINT_IF_GUID(g,cmp) \if (!memcmp(g, &cmp, sizeof(GUID))) \    printf("(GUID: %s) ", #cmp)static void print_guid(const GUID *g){    int i;    PRINT_IF_GUID(g, asf_header);    else PRINT_IF_GUID(g, file_header);    else PRINT_IF_GUID(g, stream_header);    else PRINT_IF_GUID(g, audio_stream);    else PRINT_IF_GUID(g, audio_conceal_none);    else PRINT_IF_GUID(g, video_stream);    else PRINT_IF_GUID(g, video_conceal_none);    else PRINT_IF_GUID(g, command_stream);    else PRINT_IF_GUID(g, comment_header);    else PRINT_IF_GUID(g, codec_comment_header);    else PRINT_IF_GUID(g, codec_comment1_header);    else PRINT_IF_GUID(g, data_header);    else PRINT_IF_GUID(g, index_guid);    else PRINT_IF_GUID(g, head1_guid);    else PRINT_IF_GUID(g, head2_guid);    else PRINT_IF_GUID(g, my_guid);    else PRINT_IF_GUID(g, ext_stream_header);    else PRINT_IF_GUID(g, extended_content_header);    else PRINT_IF_GUID(g, ext_stream_embed_stream_header);    else PRINT_IF_GUID(g, ext_stream_audio_stream);    else        printf("(GUID: unknown) ");    printf("0x%08x, 0x%04x, 0x%04x, {", g->v1, g->v2, g->v3);    for(i=0;i<8;i++)        printf(" 0x%02x,", g->v4[i]);    printf("}\n");}#undef PRINT_IF_GUID#endifstatic void get_guid(ByteIOContext *s, GUID *g){    int i;    g->v1 = get_le32(s);    g->v2 = get_le16(s);    g->v3 = get_le16(s);    for(i=0;i<8;i++)        g->v4[i] = get_byte(s);}#if 0static void get_str16(ByteIOContext *pb, char *buf, int buf_size){    int len, c;    char *q;    len = get_le16(pb);    q = buf;    while (len > 0) {        c = get_le16(pb);        if ((q - buf) < buf_size - 1)            *q++ = c;        len--;    }    *q = '\0';}#endifstatic void get_str16_nolen(ByteIOContext *pb, int len, char *buf, int buf_size){    int c;    char *q;    q = buf;    while (len > 0) {        c = get_le16(pb);        if ((q - buf) < buf_size - 1)            *q++ = c;        len-=2;    }    *q = '\0';}static int asf_probe(AVProbeData *pd){    GUID g;    const unsigned char *p;    int i;    /* check file header */    if (pd->buf_size <= 32)        return 0;    p = pd->buf;    g.v1 = p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);    p += 4;    g.v2 = p[0] | (p[1] << 8);    p += 2;    g.v3 = p[0] | (p[1] << 8);    p += 2;    for(i=0;i<8;i++)        g.v4[i] = *p++;    if (!memcmp(&g, &asf_header, sizeof(GUID)))        return AVPROBE_SCORE_MAX;    else        return 0;}static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap){    ASFContext *asf = s->priv_data;    GUID g;    ByteIOContext *pb = &s->pb;    AVStream *st;    ASFStream *asf_st;    int size, i;    int64_t gsize;    get_guid(pb, &g);    if (memcmp(&g, &asf_header, sizeof(GUID)))        goto fail;    get_le64(pb);    get_le32(pb);    get_byte(pb);    get_byte(pb);    memset(&asf->asfid2avid, -1, sizeof(asf->asfid2avid));    for(;;) {        get_guid(pb, &g);        gsize = get_le64(pb);#ifdef DEBUG        printf("%08Lx: ", url_ftell(pb) - 24);        print_guid(&g);        printf("  size=0x%Lx\n", gsize);#endif        if (gsize < 24)            goto fail;        if (!memcmp(&g, &file_header, sizeof(GUID))) {            get_guid(pb, &asf->hdr.guid);            asf->hdr.file_size          = get_le64(pb);            asf->hdr.create_time        = get_le64(pb);            asf->hdr.packets_count      = get_le64(pb);            asf->hdr.send_time          = get_le64(pb);            asf->hdr.play_time          = get_le64(pb);            asf->hdr.preroll            = get_le32(pb);            asf->hdr.ignore             = get_le32(pb);            asf->hdr.flags              = get_le32(pb);            asf->hdr.min_pktsize        = get_le32(pb);            asf->hdr.max_pktsize        = get_le32(pb);            asf->hdr.max_bitrate        = get_le32(pb);            asf->packet_size = asf->hdr.max_pktsize;            asf->nb_packets = asf->hdr.packets_count;        } else if (!memcmp(&g, &stream_header, sizeof(GUID))) {            int type, total_size, type_specific_size, sizeX;            unsigned int tag1;            int64_t pos1, pos2;            int test_for_ext_stream_audio;            pos1 = url_ftell(pb);            st = av_new_stream(s, 0);            if (!st)                goto fail;            av_set_pts_info(st, 32, 1, 1000); /* 32 bit pts in ms */            asf_st = av_mallocz(sizeof(ASFStream));            if (!asf_st)                goto fail;            st->priv_data = asf_st;            st->start_time = asf->hdr.preroll;            st->duration = asf->hdr.send_time /                (10000000 / 1000) - st->start_time;            get_guid(pb, &g);            test_for_ext_stream_audio = 0;            if (!memcmp(&g, &audio_stream, sizeof(GUID))) {                type = CODEC_TYPE_AUDIO;            } else if (!memcmp(&g, &video_stream, sizeof(GUID))) {                type = CODEC_TYPE_VIDEO;            } else if (!memcmp(&g, &command_stream, sizeof(GUID))) {                type = CODEC_TYPE_UNKNOWN;            } else if (!memcmp(&g, &ext_stream_embed_stream_header, sizeof(GUID))) {                test_for_ext_stream_audio = 1;                type = CODEC_TYPE_UNKNOWN;            } else {                goto fail;            }            get_guid(pb, &g);            total_size = get_le64(pb);            type_specific_size = get_le32(pb);            get_le32(pb);            st->id = get_le16(pb) & 0x7f; /* stream id */            // mapping of asf ID to AV stream ID;            asf->asfid2avid[st->id] = s->nb_streams - 1;            get_le32(pb);            if (test_for_ext_stream_audio) {                get_guid(pb, &g);                if (!memcmp(&g, &ext_stream_audio_stream, sizeof(GUID))) {                    type = CODEC_TYPE_AUDIO;                    get_guid(pb, &g);                    get_le32(pb);                    get_le32(pb);                    get_le32(pb);                    get_guid(pb, &g);                    get_le32(pb);                }            }            st->codec->codec_type = type;            if (type == CODEC_TYPE_AUDIO) {                get_wav_header(pb, st->codec, type_specific_size);                st->need_parsing = 1;                /* We have to init the frame size at some point .... */                pos2 = url_ftell(pb);                if (gsize > (pos2 + 8 - pos1 + 24)) {                    asf_st->ds_span = get_byte(pb);                    asf_st->ds_packet_size = get_le16(pb);                    asf_st->ds_chunk_size = get_le16(pb);                    asf_st->ds_data_size = get_le16(pb);                    asf_st->ds_silence_data = get_byte(pb);                }                //printf("Descrambling: ps:%d cs:%d ds:%d s:%d  sd:%d\n",                //       asf_st->ds_packet_size, asf_st->ds_chunk_size,                //       asf_st->ds_data_size, asf_st->ds_span, asf_st->ds_silence_data);                if (asf_st->ds_span > 1) {                    if (!asf_st->ds_chunk_size                        || (asf_st->ds_packet_size/asf_st->ds_chunk_size <= 1))                        asf_st->ds_span = 0; // disable descrambling                }                switch (st->codec->codec_id) {                case CODEC_ID_MP3:                    st->codec->frame_size = MPA_FRAME_SIZE;                    break;                case CODEC_ID_PCM_S16LE:                case CODEC_ID_PCM_S16BE:                case CODEC_ID_PCM_U16LE:                case CODEC_ID_PCM_U16BE:                case CODEC_ID_PCM_S8:                case CODEC_ID_PCM_U8:                case CODEC_ID_PCM_ALAW:                case CODEC_ID_PCM_MULAW:                    st->codec->frame_size = 1;                    break;                default:                    /* This is probably wrong, but it prevents a crash later */                    st->codec->frame_size = 1;                    break;                }            } else if (type == CODEC_TYPE_VIDEO) {                get_le32(pb);                get_le32(pb);                get_byte(pb);                size = get_le16(pb); /* size */