ts.c

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/*****************************************************************************
 * mpeg_ts.c : Transport Stream input module for vlc
 *****************************************************************************
 * Copyright (C) 2000-2004 VideoLAN
 * $Id: ts.c,v 1.46 2004/01/25 20:05:28 hartman Exp $
 *
 * Authors: Henri Fallon <[e-mail]>
 *          Johan Bilien <[e-mail]>
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/
#include <stdlib.h>
#include <vlc/vlc.h>
#include <vlc/input.h>

#include "iso_lang.h"

#if defined MODULE_NAME_IS_ts_dvbpsi
#   ifdef HAVE_DVBPSI_DR_H
#       include <dvbpsi/dvbpsi.h>
#       include <dvbpsi/descriptor.h>
#       include <dvbpsi/pat.h>
#       include <dvbpsi/pmt.h>
#       include <dvbpsi/dr.h>
#   else
#       include "dvbpsi.h"
#       include "descriptor.h"
#       include "tables/pat.h"
#       include "tables/pmt.h"
#       include "descriptors/dr.h"
#   endif
#endif

#include "system.h"
#include "codecs.h"

/*****************************************************************************
 * Constants
 *****************************************************************************/
#define TS_READ_ONCE 200

/*****************************************************************************
 * Private structure
 *****************************************************************************/
struct demux_sys_t
{
    module_t *   p_module;
    mpeg_demux_t mpeg;
};


#define local_iso639_getlang(p1, p2)                                         \
{                                                                           \
    const iso639_lang_t * p_iso;                                            \
    p_iso = GetLang_2T((char*)(p1));                                        \
    if( p_iso && strcmp(p_iso->psz_native_name,"Unknown"))                  \
    {                                                                       \
        if( p_iso->psz_native_name[0] )                                     \
            strncpy( (p2), p_iso->psz_native_name, 20 );                    \
        else                                                                \
            strncpy( (p2), p_iso->psz_eng_name, 20 );                       \
    }                                                                       \
    else                                                                    \
    {                                                                       \
        p_iso = GetLang_2B((char*)(p1));                                    \
        if ( p_iso )                                                        \
        {                                                                   \
            if( p_iso->psz_native_name[0] )                                 \
                strncpy( (p2), p_iso->psz_native_name, 20 );                \
            else                                                            \
                strncpy( (p2), p_iso->psz_eng_name, 20 );                   \
        }                                                                   \
        else                                                                \
        {                                                                   \
            strncpy( (p2), p1, 3 );                                         \
        }                                                                   \
    }                                                                       \
}

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
static int  Activate   ( vlc_object_t * );
static void Deactivate ( vlc_object_t * );
static int  Demux      ( input_thread_t * );

#if defined MODULE_NAME_IS_ts
static void TSDemuxPSI ( input_thread_t *, data_packet_t *,
                          es_descriptor_t *, vlc_bool_t );
static void TSDecodePAT( input_thread_t *, es_descriptor_t *);
static void TSDecodePMT( input_thread_t *, es_descriptor_t *);
#define PSI_CALLBACK TSDemuxPSI
#elif defined MODULE_NAME_IS_ts_dvbpsi
static void TS_DVBPSI_DemuxPSI  ( input_thread_t *, data_packet_t *,
                                  es_descriptor_t *, vlc_bool_t );
static void TS_DVBPSI_HandlePAT ( input_thread_t *, dvbpsi_pat_t * );
static void TS_DVBPSI_HandlePMT ( input_thread_t *, dvbpsi_pmt_t * );
#define PSI_CALLBACK TS_DVBPSI_DemuxPSI
#endif

/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
#define VLS_BACKWARDS_COMPAT_TEXT N_("Compatibility with pre-0.4 VLS")
#define VLS_BACKWARDS_COMPAT_LONGTEXT N_( \
    "The protocol for transmitting A/52 audio streams changed between VLC " \
    "0.3.x and 0.4. By default VLC assumes you have the latest VLS. In case " \
    "you're using an old version, select this option.")

#define BUGGY_PSI_TEXT N_("Buggy PSI")
#define BUGGY_PSI_LONGTEXT N_( \
    "If you have a stream whose PSI packets do not feature incremented " \
    "continuity counters, select this option.")

vlc_module_begin();
#if defined MODULE_NAME_IS_ts
    set_description( _("ISO 13818-1 MPEG Transport Stream input") );
    set_capability( "demux", 160 );
    add_shortcut( "ts" );
#elif defined MODULE_NAME_IS_ts_dvbpsi
    set_description( _("ISO 13818-1 MPEG Transport Stream input (libdvbpsi)") );
    set_capability( "demux", 170 );
    add_shortcut( "ts_dvbpsi" );
#endif

    add_bool( "vls-backwards-compat", 0, NULL,
              VLS_BACKWARDS_COMPAT_TEXT, VLS_BACKWARDS_COMPAT_LONGTEXT, VLC_TRUE );
    add_bool( "buggy-psi", 0, NULL, BUGGY_PSI_TEXT, BUGGY_PSI_LONGTEXT, VLC_TRUE );
    set_callbacks( Activate, Deactivate );
vlc_module_end();

/*****************************************************************************
 * Activate: initialize TS structures
 *****************************************************************************/
static int Activate( vlc_object_t * p_this )
{
    input_thread_t *    p_input = (input_thread_t *)p_this;
    demux_sys_t *       p_demux;
    es_descriptor_t *   p_pat_es;
    es_ts_data_t *      p_demux_data;
    stream_ts_data_t *  p_stream_data;
    byte_t *            p_peek;
    vlc_bool_t          b_force = VLC_FALSE;
    int                 i_sync_pos;

    /* Set the demux function */
    p_input->pf_demux = Demux;
    p_input->pf_demux_control = demux_vaControlDefault;

    /* Have a peep at the show */
    if( input_Peek( p_input, &p_peek, TS_PACKET_SIZE ) < TS_PACKET_SIZE )
    {
        msg_Err( p_input, "cannot peek()" );
        return VLC_EGENERIC;
    }

    if( *p_input->psz_demux && ( !strncmp( p_input->psz_demux, "ts", 3 )
         || !strncmp( p_input->psz_demux, "ts_dvbpsi", 10 ) ) )
        b_force = VLC_TRUE;

    /* In a TS_PACKET_SIZE buffer we should find a sync byte */
    for( i_sync_pos = 0; i_sync_pos < TS_PACKET_SIZE &&
         p_peek[i_sync_pos] != TS_SYNC_CODE; i_sync_pos++ );

    if( i_sync_pos >= TS_PACKET_SIZE )
    {
        if( b_force )
        {
            /* User forced */
            msg_Err( p_input, "this does not look like a TS stream, "
                     "continuing anyway" );
        }
        else
        {
            msg_Warn( p_input, "TS module discarded (no sync)" );
            return VLC_EGENERIC;
        }
    }

    /* Now that we have the first TS_SYNC_CODE, check the following
     * TS_SYNC_CODEs are where they are supposed to be (one byte sync code
     * is not enough to ensure the sync). */
    if( !b_force )
    {
        if( input_Peek( p_input, &p_peek, TS_PACKET_SIZE * TS_SYNC_CODES_MIN )
            < TS_PACKET_SIZE * TS_SYNC_CODES_MIN )
        {
            msg_Err( p_input, "cannot peek()" );
            return VLC_EGENERIC;
        }

        for( ; i_sync_pos < TS_PACKET_SIZE * TS_SYNC_CODES_MIN;
             i_sync_pos += TS_PACKET_SIZE )
        {
            if( p_peek[i_sync_pos] != TS_SYNC_CODE )
            {
                msg_Warn( p_input, "TS module discarded (lost sync)" );
                return VLC_EGENERIC;
            }
        }
    }

    /* Adapt the bufsize for our only use. */
    if( p_input->i_mtu != 0 )
    {
        /* Have minimum granularity to avoid bottlenecks at the input level. */
        p_input->i_bufsize = (p_input->i_mtu / TS_PACKET_SIZE) * TS_PACKET_SIZE;
    }

    p_demux = p_input->p_demux_data = malloc( sizeof(demux_sys_t ) );
    if( p_demux == NULL )
    {
        return -1;
    }

    p_input->p_private = (void*)&p_demux->mpeg;
    p_demux->p_module = module_Need( p_input, "mpeg-system", NULL );
    if( p_demux->p_module == NULL )
    {
        free( p_input->p_demux_data );
        return -1;
    }

    vlc_mutex_lock( &p_input->stream.stream_lock );

    if( input_InitStream( p_input, sizeof( stream_ts_data_t ) ) == -1 )
    {
        module_Unneed( p_input, p_demux->p_module );
        free( p_input->p_demux_data );
        return -1;
    }

    p_stream_data = (stream_ts_data_t *)p_input->stream.p_demux_data;
    p_stream_data->i_pat_version = PAT_UNINITIALIZED ;
    p_stream_data->b_buggy_psi = config_GetInt( p_input, "buggy-psi" );

#ifdef MODULE_NAME_IS_ts_dvbpsi
    p_stream_data->p_pat_handle = (dvbpsi_handle *)
      dvbpsi_AttachPAT( (dvbpsi_pat_callback) &TS_DVBPSI_HandlePAT, p_input );

    if( p_stream_data->p_pat_handle == NULL )
    {
        msg_Err( p_input, "could not create PAT decoder" );
        module_Unneed( p_input, p_demux->p_module );
        free( p_input->p_demux_data );
        return -1;
    }
#endif

    /* We'll have to catch the PAT in order to continue
     * Then the input will catch the PMT and then the others ES
     * The PAT es is indepedent of any program. */
    p_pat_es = input_AddES( p_input, NULL, 0x00,
                            UNKNOWN_ES, NULL, sizeof( es_ts_data_t ) );
    p_pat_es->i_fourcc = VLC_FOURCC( 'p', 'a', 't', ' ' );
    p_demux_data = (es_ts_data_t *)p_pat_es->p_demux_data;
    p_demux_data->b_psi = 1;
    p_demux_data->i_psi_type = PSI_IS_PAT;
    p_demux_data->p_psi_section = malloc(sizeof(psi_section_t));
    p_demux_data->p_psi_section->b_is_complete = 1;
    p_demux_data->i_continuity_counter = 0xFF;

    vlc_mutex_unlock( &p_input->stream.stream_lock );

    return 0;
}

/*****************************************************************************
 * Deactivate: deinitialize TS structures
 *****************************************************************************/
static void Deactivate( vlc_object_t * p_this )
{
    input_thread_t *    p_input = (input_thread_t *)p_this;

    module_Unneed( p_input, p_input->p_demux_data->p_module );
    free( p_input->p_demux_data );
}

/*****************************************************************************
 * Demux: reads and demuxes data packets
 *****************************************************************************
 * Returns -1 in case of error, 0 in case of EOF, otherwise the number of
 * packets.
 *****************************************************************************/
static int Demux( input_thread_t * p_input )
{
    demux_sys_t *   p_demux = p_input->p_demux_data;
    int             i_read_once = (p_input->i_mtu ?
                                   p_input->i_bufsize / TS_PACKET_SIZE :
                                   TS_READ_ONCE);
    int             i;

    for( i = 0; i < i_read_once; i++ )
    {
        data_packet_t *     p_data;
        ssize_t             i_result;

        i_result = p_demux->mpeg.pf_read_ts( p_input, &p_data );

        if( i_result <= 0 )
        {
            return i_result;
        }

        p_demux->mpeg.pf_demux_ts( p_input, p_data,
                                   (psi_callback_t) &PSI_CALLBACK );
    }

    return i_read_once;
}


#if defined MODULE_NAME_IS_ts
/*
 * PSI demultiplexing and decoding without libdvbpsi
 */

/*****************************************************************************
 * DemuxPSI : makes up complete PSI data
 *****************************************************************************/