udp.c

uclinux 下的vlc播放器源代码

/*****************************************************************************
 * Close: close the target
 *****************************************************************************/
static void Close( vlc_object_t * p_this )
{
    sout_access_out_t     *p_access = (sout_access_out_t*)p_this;
    sout_access_out_sys_t *p_sys = p_access->p_sys;
    int i;

    p_sys->p_thread->b_die = 1;
    for( i = 0; i < 10; i++ )
    {
        block_t *p_dummy = block_New( p_access, p_sys->i_mtu );
        p_dummy->i_dts = 0;
        p_dummy->i_pts = 0;
        p_dummy->i_length = 0;
        memset( p_dummy->p_buffer, 0, p_dummy->i_buffer );
        block_FifoPut( p_sys->p_thread->p_fifo, p_dummy );
    }
    vlc_thread_join( p_sys->p_thread );

    block_FifoRelease( p_sys->p_thread->p_fifo );
    block_FifoRelease( p_sys->p_thread->p_empty_blocks );

    if( p_sys->p_buffer ) block_Release( p_sys->p_buffer );

    net_Close( p_sys->p_thread->i_handle );

    vlc_object_detach( p_sys->p_thread );
    vlc_object_destroy( p_sys->p_thread );
    /* update p_sout->i_out_pace_nocontrol */
    p_access->p_sout->i_out_pace_nocontrol--;

    msg_Dbg( p_access, "udp access output closed" );
    free( p_sys );
}

/*****************************************************************************
 * Write: standard write on a file descriptor.
 *****************************************************************************/
static int Write( sout_access_out_t *p_access, block_t *p_buffer )
{
    sout_access_out_sys_t *p_sys = p_access->p_sys;
    int i_len = 0;

    while( p_buffer )
    {
        block_t *p_next;
        int i_packets = 0;

        if( !p_sys->b_mtu_warning && p_buffer->i_buffer > p_sys->i_mtu )
        {
            msg_Warn( p_access, "packet size > MTU, you should probably "
                      "increase the MTU" );
            p_sys->b_mtu_warning = VLC_TRUE;
        }

        /* Check if there is enough space in the buffer */
        if( p_sys->p_buffer &&
            p_sys->p_buffer->i_buffer + p_buffer->i_buffer > p_sys->i_mtu )
        {
            if( p_sys->p_buffer->i_dts + p_sys->p_thread->i_caching < mdate() )
            {
                msg_Dbg( p_access, "late packet for udp input (" I64Fd ")",
                         mdate() - p_sys->p_buffer->i_dts
                          - p_sys->p_thread->i_caching );
            }
            block_FifoPut( p_sys->p_thread->p_fifo, p_sys->p_buffer );
            p_sys->p_buffer = NULL;
        }

        i_len += p_buffer->i_buffer;
        while( p_buffer->i_buffer )
        {
            int i_write = __MIN( p_buffer->i_buffer, p_sys->i_mtu );

            i_packets++;

            if( !p_sys->p_buffer )
            {
                p_sys->p_buffer = NewUDPPacket( p_access, p_buffer->i_dts );
                if( !p_sys->p_buffer ) break;
            }

            memcpy( p_sys->p_buffer->p_buffer + p_sys->p_buffer->i_buffer,
                    p_buffer->p_buffer, i_write );

            p_sys->p_buffer->i_buffer += i_write;
            p_buffer->p_buffer += i_write;
            p_buffer->i_buffer -= i_write;
            if ( p_buffer->i_flags & BLOCK_FLAG_CLOCK )
            {
                if ( p_sys->p_buffer->i_flags & BLOCK_FLAG_CLOCK )
                    msg_Warn( p_access, "putting two PCRs at once" );
                p_sys->p_buffer->i_flags |= BLOCK_FLAG_CLOCK;
            }

            if( p_sys->p_buffer->i_buffer == p_sys->i_mtu || i_packets > 1 )
            {
                /* Flush */
                if( p_sys->p_buffer->i_dts + p_sys->p_thread->i_caching
                      < mdate() )
                {
                    msg_Dbg( p_access, "late packet for udp input (" I64Fd ")",
                             mdate() - p_sys->p_buffer->i_dts
                              - p_sys->p_thread->i_caching );
                }
                block_FifoPut( p_sys->p_thread->p_fifo, p_sys->p_buffer );
                p_sys->p_buffer = NULL;
            }
        }

        p_next = p_buffer->p_next;
        block_Release( p_buffer );
        p_buffer = p_next;
    }

    return( p_sys->p_thread->b_error ? -1 : i_len );
}

/*****************************************************************************
 * WriteRaw: write p_buffer without trying to fill mtu
 *****************************************************************************/
static int WriteRaw( sout_access_out_t *p_access, block_t *p_buffer )
{
    sout_access_out_sys_t   *p_sys = p_access->p_sys;
    block_t *p_buf;
    int i_len;

    while ( p_sys->p_thread->p_empty_blocks->i_depth >= MAX_EMPTY_BLOCKS )
    {
        p_buf = block_FifoGet(p_sys->p_thread->p_empty_blocks);
        block_Release( p_buf );
    }

    i_len = p_buffer->i_buffer;
    block_FifoPut( p_sys->p_thread->p_fifo, p_buffer );

    return( p_sys->p_thread->b_error ? -1 : i_len );
}

/*****************************************************************************
 * Seek: seek to a specific location in a file
 *****************************************************************************/
static int Seek( sout_access_out_t *p_access, off_t i_pos )
{
    msg_Err( p_access, "UDP sout access cannot seek" );
    return -1;
}

/*****************************************************************************
 * NewUDPPacket: allocate a new UDP packet of size p_sys->i_mtu
 *****************************************************************************/
static block_t *NewUDPPacket( sout_access_out_t *p_access, mtime_t i_dts)
{
    sout_access_out_sys_t *p_sys = p_access->p_sys;
    block_t *p_buffer;

    while ( p_sys->p_thread->p_empty_blocks->i_depth > MAX_EMPTY_BLOCKS )
    {
        p_buffer = block_FifoGet( p_sys->p_thread->p_empty_blocks );
        block_Release( p_buffer );
    }

    if( p_sys->p_thread->p_empty_blocks->i_depth == 0 )
    {
        p_buffer = block_New( p_access->p_sout, p_sys->i_mtu );
    }
    else
    {
        p_buffer = block_FifoGet(p_sys->p_thread->p_empty_blocks );       
        p_buffer->i_flags = 0;
        p_buffer = block_Realloc( p_buffer, 0, p_sys->i_mtu );
    }

    p_buffer->i_dts = i_dts;
    p_buffer->i_buffer = 0;

    if( p_sys->b_rtpts )
    {
        mtime_t i_timestamp = p_buffer->i_dts * 9 / 100;

        /* add rtp/ts header */
        p_buffer->p_buffer[0] = 0x80;
        p_buffer->p_buffer[1] = 0x21; // mpeg2-ts

        p_buffer->p_buffer[2] = ( p_sys->i_sequence_number >> 8 )&0xff;
        p_buffer->p_buffer[3] = p_sys->i_sequence_number&0xff;
        p_sys->i_sequence_number++;

        p_buffer->p_buffer[4] = ( i_timestamp >> 24 )&0xff;
        p_buffer->p_buffer[5] = ( i_timestamp >> 16 )&0xff;
        p_buffer->p_buffer[6] = ( i_timestamp >>  8 )&0xff;
        p_buffer->p_buffer[7] = i_timestamp&0xff;

        p_buffer->p_buffer[ 8] = ( p_sys->i_ssrc >> 24 )&0xff;
        p_buffer->p_buffer[ 9] = ( p_sys->i_ssrc >> 16 )&0xff;
        p_buffer->p_buffer[10] = ( p_sys->i_ssrc >>  8 )&0xff;
        p_buffer->p_buffer[11] = p_sys->i_ssrc&0xff;

        p_buffer->i_buffer = 12;
    }

    return p_buffer;
}

/*****************************************************************************
 * ThreadWrite: Write a packet on the network at the good time.
 *****************************************************************************/
static void ThreadWrite( vlc_object_t *p_this )
{
    sout_access_thread_t *p_thread = (sout_access_thread_t*)p_this;
    mtime_t              i_date_last = -1;
    mtime_t              i_to_send = p_thread->i_group;
    int                  i_dropped_packets = 0;
#if defined(WIN32) || defined(UNDER_CE)
    char strerror_buf[WINSOCK_STRERROR_SIZE];
# define strerror( x ) winsock_strerror( strerror_buf )
#endif

    while( !p_thread->b_die )
    {
        block_t *p_pk;
        mtime_t       i_date, i_sent;
#if 0
        if( (i++ % 1000)==0 ) {
          int i = 0;
          int j = 0;
          block_t *p_tmp = p_thread->p_empty_blocks->p_first;
          while( p_tmp ) { p_tmp = p_tmp->p_next; i++;}
          p_tmp = p_thread->p_fifo->p_first;
          while( p_tmp ) { p_tmp = p_tmp->p_next; j++;}
	  msg_Err( p_thread, "fifo depth: %d/%d, empty blocks: %d/%d",
                   p_thread->p_fifo->i_depth, j,p_thread->p_empty_blocks->i_depth,i );
	}
#endif
        p_pk = block_FifoGet( p_thread->p_fifo );

        i_date = p_thread->i_caching + p_pk->i_dts;
        if( i_date_last > 0 )
        {
            if( i_date - i_date_last > 2000000 )
            {
                if( !i_dropped_packets )
                    msg_Dbg( p_thread, "mmh, hole ("I64Fd" > 2s) -> drop",
                             i_date - i_date_last );

                block_FifoPut( p_thread->p_empty_blocks, p_pk );

                i_date_last = i_date;
                i_dropped_packets++;
                continue;
            }
            else if( i_date - i_date_last < -1000 )
            {
                if( !i_dropped_packets )
                    msg_Dbg( p_thread, "mmh, packets in the past ("I64Fd")",
                             i_date_last - i_date );
            }
        }

        i_to_send--;
        if( !i_to_send || (p_pk->i_flags & BLOCK_FLAG_CLOCK) )
        {
            mwait( i_date );
            i_to_send = p_thread->i_group;
        }
        if( send( p_thread->i_handle, p_pk->p_buffer, p_pk->i_buffer, 0 )
              == -1 )
        {
            msg_Warn( p_thread, "send error: %s", strerror(errno) );
        }

        if( i_dropped_packets )
        {
            msg_Dbg( p_thread, "dropped %i packets", i_dropped_packets );
            i_dropped_packets = 0;
        }

#if 1
        i_sent = mdate();
        if ( i_sent > i_date + 20000 )
        {
            msg_Dbg( p_thread, "packet has been sent too late (" I64Fd ")",
                     i_sent - i_date );
        }
#endif

        block_FifoPut( p_thread->p_empty_blocks, p_pk );

        i_date_last = i_date;
    }
}