]> git.sesse.net Git - vlc/blobdiff - src/input/input_ext-dec.c
* ALL: New ogg demux and vorbis codec modules for preliminary support of
[vlc] / src / input / input_ext-dec.c
index 97aa4221f9aec23a8afdbab632cd70b9e098c1b1..0a0cbb6108ca0bc30eedebbde2ff853c9dadc547 100644 (file)
@@ -1,9 +1,10 @@
 /*****************************************************************************
  * input_ext-dec.c: services to the decoders
  *****************************************************************************
- * Copyright (C) 1998, 1999, 2000 VideoLAN
+ * Copyright (C) 1998-2001 VideoLAN
+ * $Id: input_ext-dec.c,v 1.36 2002/10/23 23:17:44 gbazin Exp $
  *
- * Authors: 
+ * Authors: Christophe Massiot <massiot@via.ecp.fr>
  *
  * 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
 /*****************************************************************************
  * Preamble
  *****************************************************************************/
-#include "defs.h"
+#include <string.h>                                    /* memcpy(), memset() */
+#include <sys/types.h>                                              /* off_t */
 
-#include "config.h"
-#include "common.h"
-#include "threads.h"
-#include "mtime.h"
-
-#include "intf_msg.h"
+#include <vlc/vlc.h>
 
 #include "stream_control.h"
 #include "input_ext-dec.h"
-#include "input.h"
+#include "input_ext-intf.h"
+#include "input_ext-plugins.h"
 
 /*****************************************************************************
  * InitBitstream: initialize a bit_stream_t structure
  *****************************************************************************/
-void InitBitstream( bit_stream_t * p_bit_stream, decoder_fifo_t * p_fifo )
+void InitBitstream( bit_stream_t * p_bit_stream, decoder_fifo_t * p_fifo,
+                void (* pf_bitstream_callback)( bit_stream_t *, vlc_bool_t ),
+                void * p_callback_arg )
 {
     p_bit_stream->p_decoder_fifo = p_fifo;
-    p_bit_stream->pf_next_data_packet = NextDataPacket;
+    p_bit_stream->pf_bitstream_callback = pf_bitstream_callback;
+    p_bit_stream->p_callback_arg = p_callback_arg;
 
     /* Get the first data packet. */
     vlc_mutex_lock( &p_fifo->data_lock );
-    while ( DECODER_FIFO_ISEMPTY( *p_fifo ) )
+    while ( p_fifo->p_first == NULL )
     {
         if ( p_fifo->b_die )
         {
@@ -55,38 +56,135 @@ void InitBitstream( bit_stream_t * p_bit_stream, decoder_fifo_t * p_fifo )
         }
         vlc_cond_wait( &p_fifo->data_wait, &p_fifo->data_lock );
     }
-    p_bit_stream->p_data = DECODER_FIFO_START( *p_fifo )->p_first;
+    p_bit_stream->p_data = p_fifo->p_first->p_first;
     p_bit_stream->p_byte = p_bit_stream->p_data->p_payload_start;
     p_bit_stream->p_end  = p_bit_stream->p_data->p_payload_end;
     p_bit_stream->fifo.buffer = 0;
     p_bit_stream->fifo.i_available = 0;
+    p_bit_stream->i_pts = p_fifo->p_first->i_pts;
+    p_bit_stream->i_dts = p_fifo->p_first->i_dts;
+    p_bit_stream->p_pts_validity = p_bit_stream->p_byte;
     vlc_mutex_unlock( &p_fifo->data_lock );
+
+    /* Call back the decoder. */
+    if( p_bit_stream->pf_bitstream_callback != NULL )
+    {
+        p_bit_stream->pf_bitstream_callback( p_bit_stream, 1 );
+    }
+
+    if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
+    {
+        /* Get aligned on a word boundary.
+         * NB : we _will_ get aligned, because we have at most 
+         * sizeof(WORD_TYPE) - 1 bytes to store, and at least
+         * sizeof(WORD_TYPE) - 1 empty bytes in the bit buffer. */
+        AlignWord( p_bit_stream );
+    }
 }
 
 /*****************************************************************************
- * NextDataPacket: go to the next data packet
+ * DecoderError : an error occured, use this function to empty the fifo
  *****************************************************************************/
-void NextDataPacket( bit_stream_t * p_bit_stream )
+void DecoderError( decoder_fifo_t * p_fifo )
 {
-    WORD_TYPE           buffer_left;
-    ptrdiff_t           i_bytes_left;
-    decoder_fifo_t *    p_fifo = p_bit_stream->p_decoder_fifo;
+    /* We take the lock, because we are going to read/write the start/end
+     * indexes of the decoder fifo */
+    vlc_mutex_lock (&p_fifo->data_lock);
+
+    /* Wait until a `die' order is sent */
+    while (!p_fifo->b_die)
+    {
+        /* Trash all received PES packets */
+        input_DeletePES( p_fifo->p_packets_mgt, p_fifo->p_first );
+        p_fifo->p_first = NULL;
+        p_fifo->pp_last = &p_fifo->p_first;
+
+        /* If the input is waiting for us, tell him to stop */
+        vlc_cond_signal( &p_fifo->data_wait );
+
+        /* Waiting for the input thread to put new PES packets in the fifo */
+        vlc_cond_wait (&p_fifo->data_wait, &p_fifo->data_lock);
+    }
+
+    /* We can release the lock before leaving */
+    vlc_mutex_unlock (&p_fifo->data_lock);
+}
+
+/*****************************************************************************
+ * GetPES: return the first PES from the fifo
+ *****************************************************************************/
+static inline pes_packet_t *_GetPES( decoder_fifo_t * p_fifo )
+{
+    pes_packet_t * p_pes;
+
+    vlc_mutex_lock( &p_fifo->data_lock );
+
+    if( p_fifo->p_first == NULL )
+    {
+        /* No PES in the FIFO. p_last is no longer valid. */
+        p_fifo->pp_last = &p_fifo->p_first;
+
+        if( p_fifo->b_die )
+        {
+            vlc_mutex_unlock( &p_fifo->data_lock );
+            return NULL;
+        }
+
+        /* Signal the input thread we're waiting. This is only
+         * needed in case of slave clock (ES plug-in)  but it won't
+         * harm. */
+        vlc_cond_signal( &p_fifo->data_wait );
+
+        /* Wait for the input to tell us when we receive a packet. */
+        vlc_cond_wait( &p_fifo->data_wait, &p_fifo->data_lock );
+    }
+
+    p_pes = p_fifo->p_first;
+
+    vlc_mutex_unlock( &p_fifo->data_lock );
+
+    return p_pes;
+}
+
+pes_packet_t * GetPES( decoder_fifo_t * p_fifo )
+{
+    return( _GetPES( p_fifo ) );
+}
+
+/*****************************************************************************
+ * NextPES: free the current PES and return the next one
+ *****************************************************************************/
+static inline pes_packet_t * _NextPES( decoder_fifo_t * p_fifo )
+{
+    pes_packet_t * p_next;
+
+    vlc_mutex_lock( &p_fifo->data_lock );
+
+    /* Free the previous PES packet. */
+    p_next = p_fifo->p_first->p_next;
+    p_fifo->p_first->p_next = NULL;
+    input_DeletePES( p_fifo->p_packets_mgt, p_fifo->p_first );
+    p_fifo->p_first = p_next;
+    p_fifo->i_depth--;
+
+    vlc_mutex_unlock( &p_fifo->data_lock );
+
+    return _GetPES( p_fifo );
+}
+
+pes_packet_t * NextPES( decoder_fifo_t * p_fifo )
+{
+    return( _NextPES( p_fifo ) );
+}
 
-    /* Buffer used at the end of a decoder thread, to give it zero
-     * values if needed. */
-    static byte_t       p_zero[64] = { 0, 0, 0, 0, 0, 0, 0,
-                                       0, 0, 0, 0, 0, 0, 0,
-                                       0, 0, 0, 0, 0, 0, 0,
-                                       0, 0, 0, 0, 0, 0, 0,
-                                       0, 0, 0, 0, 0, 0, 0,
-                                       0, 0, 0, 0, 0, 0, 0,
-                                       0, 0, 0, 0, 0, 0, 0,
-                                       0, 0, 0, 0, 0, 0, 0 };
-
-    /* Put the remaining bytes (not aligned on a word boundary) in a
-     * temporary buffer. */
-    i_bytes_left = p_bit_stream->p_end - p_bit_stream->p_byte;
-    buffer_left = *((WORD_TYPE *)p_bit_stream->p_end - 1);
+/*****************************************************************************
+ * NextDataPacket: go to the data packet after *pp_data, return 1 if we
+ * changed PES
+ *****************************************************************************/
+static inline vlc_bool_t _NextDataPacket( decoder_fifo_t * p_fifo,
+                                          data_packet_t ** pp_data )
+{
+    vlc_bool_t b_new_pes;
 
     /* We are looking for the next data packet that contains real data,
      * and not just a PES header */
@@ -94,63 +192,375 @@ void NextDataPacket( bit_stream_t * p_bit_stream )
     {
         /* We were reading the last data packet of this PES packet... It's
          * time to jump to the next PES packet */
-        if( p_bit_stream->p_data->p_next == NULL )
+        if( (*pp_data)->p_next == NULL )
         {
-            /* We are going to read/write the start and end indexes of the
-             * decoder fifo and to use the fifo's conditional variable,
-             * that's why we need to take the lock before. */
-            vlc_mutex_lock( &p_fifo->data_lock );
+            /* The next packet could be found in the next PES packet */
+            *pp_data = (_NextPES( p_fifo ))->p_first;
 
-            /* Is the input thread dying ? */
-            if( p_fifo->b_die )
-            {
-                vlc_mutex_unlock( &p_fifo->data_lock );
-                p_bit_stream->p_byte = p_zero;
-                p_bit_stream->p_end = &p_zero[sizeof(p_zero) - 1];
-                return;
-            }
+            b_new_pes = 1;
+        }
+        else
+        {
+            /* Perhaps the next data packet of the current PES packet contains
+             * real data (ie its payload's size is greater than 0). */
+            *pp_data = (*pp_data)->p_next;
+
+            b_new_pes = 0;
+        }
+    } while ( (*pp_data)->p_payload_start == (*pp_data)->p_payload_end );
+
+    return( b_new_pes );
+}
+
+vlc_bool_t NextDataPacket( decoder_fifo_t * p_fifo, data_packet_t ** pp_data )
+{
+    return( _NextDataPacket( p_fifo, pp_data ) );
+}
+
+/*****************************************************************************
+ * BitstreamNextDataPacket: go to the next data packet, and update bitstream
+ * context
+ *****************************************************************************/
+static inline void _BitstreamNextDataPacket( bit_stream_t * p_bit_stream )
+{
+    decoder_fifo_t *    p_fifo = p_bit_stream->p_decoder_fifo;
+    vlc_bool_t          b_new_pes;
+
+    b_new_pes = _NextDataPacket( p_fifo, &p_bit_stream->p_data );
+
+    /* We've found a data packet which contains interesting data... */
+    p_bit_stream->p_byte = p_bit_stream->p_data->p_payload_start;
+    p_bit_stream->p_end  = p_bit_stream->p_data->p_payload_end;
+
+    /* Call back the decoder. */
+    if( p_bit_stream->pf_bitstream_callback != NULL )
+    {
+        p_bit_stream->pf_bitstream_callback( p_bit_stream, b_new_pes );
+    }
+
+    /* Discontinuity management. */
+    if( p_bit_stream->p_data->b_discard_payload )
+    {
+        p_bit_stream->i_pts = p_bit_stream->i_dts = 0;
+    }
+
+    /* Retrieve the PTS. */
+    if( b_new_pes && p_fifo->p_first->i_pts )
+    {
+        p_bit_stream->i_pts = p_fifo->p_first->i_pts;
+        p_bit_stream->i_dts = p_fifo->p_first->i_dts;
+        p_bit_stream->p_pts_validity = p_bit_stream->p_byte;
+    }
+}
+
+void BitstreamNextDataPacket( bit_stream_t * p_bit_stream )
+{
+    _BitstreamNextDataPacket( p_bit_stream );
+}
 
-            /* We should increase the start index of the decoder fifo, but
-             * if we do this now, the input thread could overwrite the
-             * pointer to the current PES packet, and we weren't able to
-             * give it back to the netlist. That's why we free the PES
-             * packet first. */
-            p_fifo->pf_delete_pes( p_fifo->p_packets_mgt,
-                                   DECODER_FIFO_START( *p_fifo ) );
-            DECODER_FIFO_INCSTART( *p_fifo );
+/*****************************************************************************
+ * UnalignedShowBits : places i_bits bits into the bit buffer, even when
+ * not aligned on a word boundary
+ *****************************************************************************/
+u32 UnalignedShowBits( bit_stream_t * p_bit_stream, unsigned int i_bits )
+{
+    /* We just fill in the bit buffer. */
+    while( p_bit_stream->fifo.i_available < i_bits )
+    {
+        if( p_bit_stream->p_byte < p_bit_stream->p_end )
+        {
+            p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
+                                            << (8 * sizeof(WORD_TYPE) - 8
+                                            - p_bit_stream->fifo.i_available);
+            p_bit_stream->fifo.i_available += 8;
+        }
+        else
+        {
+            _BitstreamNextDataPacket( p_bit_stream );
 
-            while( DECODER_FIFO_ISEMPTY( *p_fifo ) )
+            if( (ptrdiff_t)p_bit_stream->p_byte & (sizeof(WORD_TYPE) - 1) )
             {
-                vlc_cond_wait( &p_fifo->data_wait, &p_fifo->data_lock );
-                if( p_fifo->b_die )
+                /* We are not aligned anymore. */
+                if( ((ptrdiff_t)p_bit_stream->p_byte
+                                    & (sizeof(WORD_TYPE) - 1)) * 8
+                        < p_bit_stream->fifo.i_available )
+                {
+                    /* We are not aligned, and won't be. Copy the first word
+                     * of the packet in a temporary buffer, and we'll see
+                     * later. */
+                    int     i;
+
+                    /* sizeof(WORD_TYPE) - number of bytes to trash
+                     * from the last payload */
+                    int     j;
+
+                    p_bit_stream->i_showbits_buffer = 0;
+
+                    for( j = i = 0 ; i < sizeof(WORD_TYPE) ; i++ )
+                    {
+                        if( p_bit_stream->p_byte >= p_bit_stream->p_end )
+                        {
+                            j = i;
+                            _BitstreamNextDataPacket( p_bit_stream );
+                        }
+                        ((byte_t *)&p_bit_stream->i_showbits_buffer)[i] =
+                            * p_bit_stream->p_byte;
+                        p_bit_stream->p_byte++;
+                    }
+
+                    /* This is kind of kludgy. */
+                    p_bit_stream->p_data->p_payload_start +=
+                                                         sizeof(WORD_TYPE) - j;
+                    p_bit_stream->p_byte =
+                        (byte_t *)&p_bit_stream->i_showbits_buffer;
+                    p_bit_stream->p_end =
+                        (byte_t *)&p_bit_stream->i_showbits_buffer
+                            + sizeof(WORD_TYPE);
+                    p_bit_stream->showbits_data.p_next = p_bit_stream->p_data;
+                    p_bit_stream->p_data = &p_bit_stream->showbits_data;
+                }
+                else
                 {
-                    vlc_mutex_unlock( &p_fifo->data_lock );
-                    p_bit_stream->p_byte = p_zero;
-                    p_bit_stream->p_end = &p_zero[sizeof(p_zero) - 1];
-                    return;
+                    /* We are not aligned, but we can be. */
+                    AlignWord( p_bit_stream );
                 }
             }
 
-            /* The next byte could be found in the next PES packet */
-            p_bit_stream->p_data = DECODER_FIFO_START( *p_fifo )->p_first;
+            /* We have 32 bits ready for reading, it will be enough. */
+            break;
+        }
+    }
 
-            /* We can release the fifo's data lock */
-            vlc_mutex_unlock( &p_fifo->data_lock );
+    /* It shouldn't loop :-)) */
+    return( ShowBits( p_bit_stream, i_bits ) );
+}
+
+/*****************************************************************************
+ * UnalignedGetBits : returns i_bits bits from the bit stream and removes
+ * them from the buffer, even when the bit stream is not aligned on a word
+ * boundary
+ *****************************************************************************/
+u32 UnalignedGetBits( bit_stream_t * p_bit_stream, unsigned int i_bits )
+{
+    u32         i_result;
+
+    i_result = p_bit_stream->fifo.buffer
+                    >> (8 * sizeof(WORD_TYPE) - i_bits);
+    i_bits = -p_bit_stream->fifo.i_available;
+
+    /* Gather missing bytes. */
+    while( i_bits >= 8 )
+    {
+        if( p_bit_stream->p_byte < p_bit_stream->p_end )
+        {
+            i_result |= *(p_bit_stream->p_byte++) << (i_bits - 8);
+            i_bits -= 8;
         }
         else
         {
-            /* Perhaps the next data packet of the current PES packet contains
-             * real data (ie its payload's size is greater than 0). */
-            p_bit_stream->p_data = p_bit_stream->p_data->p_next;
+            _BitstreamNextDataPacket( p_bit_stream );
+            i_result |= *(p_bit_stream->p_byte++) << (i_bits - 8);
+            i_bits -= 8;
         }
-    } while ( p_bit_stream->p_data->p_payload_start
-               == p_bit_stream->p_data->p_payload_end );
+    }
 
-    /* We've found a data packet which contains interesting data... */
-    p_bit_stream->p_byte = p_bit_stream->p_data->p_payload_start;
-    p_bit_stream->p_end  = p_bit_stream->p_data->p_payload_end;
+    /* Gather missing bits. */
+    if( i_bits > 0 )
+    {
+        unsigned int    i_tmp = 8 - i_bits;
+
+        if( p_bit_stream->p_byte < p_bit_stream->p_end )
+        {
+            i_result |= *p_bit_stream->p_byte >> i_tmp;
+            p_bit_stream->fifo.buffer = *(p_bit_stream->p_byte++)
+                 << ( sizeof(WORD_TYPE) * 8 - i_tmp );
+            p_bit_stream->fifo.i_available = i_tmp;
+        }
+        else
+        {
+            _BitstreamNextDataPacket( p_bit_stream );
+            i_result |= *p_bit_stream->p_byte >> i_tmp;
+            p_bit_stream->fifo.buffer = *(p_bit_stream->p_byte++)
+                 << ( sizeof(WORD_TYPE) * 8 - i_tmp );
+            p_bit_stream->fifo.i_available = i_tmp;
+        }
+    }
+    else
+    {
+        p_bit_stream->fifo.i_available = 0;
+        p_bit_stream->fifo.buffer = 0;
+    }
+
+    if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
+    {
+        /* Get aligned on a word boundary. Otherwise it is safer
+         * to do it the next time.
+         * NB : we _will_ get aligned, because we have at most
+         * sizeof(WORD_TYPE) - 1 bytes to store, and at least
+         * sizeof(WORD_TYPE) - 1 empty bytes in the bit buffer. */
+        AlignWord( p_bit_stream );
+    }
+
+    return( i_result );
+}
+
+/*****************************************************************************
+ * UnalignedRemoveBits : removes i_bits (== -i_available) from the bit
+ * buffer, even when the bit stream is not aligned on a word boundary
+ *****************************************************************************/
+void UnalignedRemoveBits( bit_stream_t * p_bit_stream )
+{
+    /* First remove all unnecessary bytes. */
+    while( p_bit_stream->fifo.i_available <= -8 )
+    {
+        if( p_bit_stream->p_byte < p_bit_stream->p_end )
+        {
+            p_bit_stream->p_byte++;
+            p_bit_stream->fifo.i_available += 8;
+        }
+        else
+        {
+            _BitstreamNextDataPacket( p_bit_stream );
+            p_bit_stream->p_byte++;
+            p_bit_stream->fifo.i_available += 8;
+        }
+    }
+
+    /* Remove unnecessary bits. */
+    if( p_bit_stream->fifo.i_available < 0 )
+    {
+        if( p_bit_stream->p_byte < p_bit_stream->p_end )
+        {
+            p_bit_stream->fifo.buffer = *(p_bit_stream->p_byte++)
+                 << ( sizeof(WORD_TYPE) * 8 - 8
+                         - p_bit_stream->fifo.i_available );
+            p_bit_stream->fifo.i_available += 8;
+        }
+        else
+        {
+            _BitstreamNextDataPacket( p_bit_stream );
+            p_bit_stream->fifo.buffer = *(p_bit_stream->p_byte++)
+                 << ( sizeof(WORD_TYPE) * 8 - 8
+                         - p_bit_stream->fifo.i_available );
+            p_bit_stream->fifo.i_available += 8;
+        }
+    }
+    else
+    {
+        p_bit_stream->fifo.buffer = 0;
+    }
+
+    if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
+    {
+        /* Get aligned on a word boundary. Otherwise it is safer
+         * to do it the next time.
+         * NB : we _will_ get aligned, because we have at most 
+         * sizeof(WORD_TYPE) - 1 bytes to store, and at least
+         * sizeof(WORD_TYPE) - 1 empty bytes in the bit buffer. */
+        AlignWord( p_bit_stream );
+    }
+}
+
+/*****************************************************************************
+ * CurrentPTS: returns the current PTS and DTS
+ *****************************************************************************/
+void CurrentPTS( bit_stream_t * p_bit_stream, mtime_t * pi_pts,
+                 mtime_t * pi_dts )
+{
+    /* Check if the current PTS is already valid (ie. if the first byte
+     * of the packet has already been used in the decoder). */
+    ptrdiff_t p_diff = p_bit_stream->p_pts_validity - p_bit_stream->p_byte;
+    if( p_diff < 0 || p_diff > 4 /* We are far away so it is valid */
+         || (p_diff * 8) >= p_bit_stream->fifo.i_available
+            /* We have buffered less bytes than actually read */ )
+    {
+        *pi_pts = p_bit_stream->i_pts;
+        if( pi_dts != NULL ) *pi_dts = p_bit_stream->i_dts;
+        p_bit_stream->i_pts = 0;
+        p_bit_stream->i_dts = 0;
+    }
+    else
+    {
+        *pi_pts = 0;
+        if( pi_dts != NULL) *pi_dts = 0;
+    }
+}
+
+/*****************************************************************************
+ * NextPTS: returns the PTS and DTS for the next starting byte
+ *****************************************************************************/
+void NextPTS( bit_stream_t * p_bit_stream, mtime_t * pi_pts,
+              mtime_t * pi_dts )
+{
+    /* Check if the current PTS is already valid (ie. if the first byte
+     * of the packet has already been used in the decoder). */
+    ptrdiff_t p_diff = p_bit_stream->p_pts_validity - p_bit_stream->p_byte - 1;
+    if( p_diff < 0 || p_diff > 4 /* We are far away so it is valid */
+         || (p_diff * 8) >= p_bit_stream->fifo.i_available
+            /* We have buffered less bytes than actually read */ )
+    {
+        *pi_pts = p_bit_stream->i_pts;
+        if( pi_dts != NULL ) *pi_dts = p_bit_stream->i_dts;
+        p_bit_stream->i_pts = 0;
+        p_bit_stream->i_dts = 0;
+    }
+    else
+    {
+        *pi_pts = 0;
+        if( pi_dts != NULL) *pi_dts = 0;
+    }
+}
+
+/****************************************************************************
+ * input_NextPES : extract a PES from the fifo. If pp_pes is NULL then this 
+ * PES is deleted, else pp_pes will be set to this PES
+ ****************************************************************************/
+int input_NextPES( decoder_fifo_t *p_fifo, pes_packet_t **pp_pes )
+{
+    pes_packet_t *p_pes, *p_next;
+
+    vlc_mutex_lock( &p_fifo->data_lock );
+
+    /* if fifo is emty wait */
+    while( !p_fifo->p_first )
+    {
+        if( p_fifo->b_die )
+        {
+            vlc_mutex_unlock( &p_fifo->data_lock );
+            if( pp_pes )
+            {
+                *pp_pes = NULL;
+            }
+            return( -1 );
+        }
+        vlc_cond_signal( &p_fifo->data_wait );
+        vlc_cond_wait( &p_fifo->data_wait, &p_fifo->data_lock );
+    }
+    p_pes = p_fifo->p_first;
+
+    p_next = p_pes->p_next;
+    p_pes->p_next = NULL;
+
+
+    p_fifo->p_first = p_next;
+    p_fifo->i_depth--;
 
-    /* Copy remaining bits of the previous packet */
-    *((WORD_TYPE *)p_bit_stream->p_byte - 1) = buffer_left;
-    p_bit_stream->p_byte -= i_bytes_left;
+    if( !p_fifo->p_first )
+    {
+        /* No PES in the fifo */
+        /* pp_last no longer valid */
+        p_fifo->pp_last = &p_fifo->p_first;
+    }
+    vlc_mutex_unlock( &p_fifo->data_lock );
+
+    if( pp_pes )
+    {
+        *pp_pes = p_pes;
+    }
+    else
+    {
+        input_DeletePES( p_fifo->p_packets_mgt, p_pes );
+    }
+    return( 0 );
 }
+