1 /*****************************************************************************
2 * livehttp.c: Live HTTP Streaming
3 *****************************************************************************
4 * Copyright © 2001, 2002, 2013 VLC authors and VideoLAN
5 * Copyright © 2009-2010 by Keary Griffin
7 * Authors: Keary Griffin <kearygriffin at gmail.com>
8 * Ilkka Ollakka <ileoo at videolan dot org>
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU Lesser General Public License as published by
12 * the Free Software Foundation; either version 2.1 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU Lesser General Public License for more details.
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with this program; if not, write to the Free Software Foundation,
22 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
23 *****************************************************************************/
25 /*****************************************************************************
27 *****************************************************************************/
33 #include <sys/types.h>
41 #include <vlc_common.h>
42 #include <vlc_plugin.h>
44 #include <vlc_block.h>
46 #include <vlc_strings.h>
47 #include <vlc_charset.h>
50 #include <vlc_gcrypt.h>
55 # define O_LARGEFILE 0
58 #define STR_ENDLIST "#EXT-X-ENDLIST\n"
60 #define MAX_RENAME_RETRIES 10
62 /*****************************************************************************
64 *****************************************************************************/
65 static int Open ( vlc_object_t * );
66 static void Close( vlc_object_t * );
68 #define SOUT_CFG_PREFIX "sout-livehttp-"
69 #define SEGLEN_TEXT N_("Segment length")
70 #define SEGLEN_LONGTEXT N_("Length of TS stream segments")
72 #define SPLITANYWHERE_TEXT N_("Split segments anywhere")
73 #define SPLITANYWHERE_LONGTEXT N_("Don't require a keyframe before splitting "\
74 "a segment. Needed for audio only.")
76 #define NUMSEGS_TEXT N_("Number of segments")
77 #define NUMSEGS_LONGTEXT N_("Number of segments to include in index")
79 #define NOCACHE_TEXT N_("Allow cache")
80 #define NOCACHE_LONGTEXT N_("Add EXT-X-ALLOW-CACHE:NO directive in playlist-file if this is disabled")
82 #define INDEX_TEXT N_("Index file")
83 #define INDEX_LONGTEXT N_("Path to the index file to create")
85 #define INDEXURL_TEXT N_("Full URL to put in index file")
86 #define INDEXURL_LONGTEXT N_("Full URL to put in index file. "\
87 "Use #'s to represent segment number")
89 #define DELSEGS_TEXT N_("Delete segments")
90 #define DELSEGS_LONGTEXT N_("Delete segments when they are no longer needed")
92 #define RATECONTROL_TEXT N_("Use muxers rate control mechanism")
94 #define KEYURI_TEXT N_("AES key URI to place in playlist")
95 #define KEYURI_LONGTEXT N_("Location from where client will retrieve the stream decryption key")
97 #define KEYFILE_TEXT N_("AES key file")
98 #define KEYFILE_LONGTEXT N_("File containing the 16 bytes encryption key")
100 #define RANDOMIV_TEXT N_("Use randomized IV for encryption")
101 #define RANDOMIV_LONGTEXT N_("Generate IV instead using segment-number as IV")
104 set_description( N_("HTTP Live streaming output") )
105 set_shortname( N_("LiveHTTP" ))
106 add_shortcut( "livehttp" )
107 set_capability( "sout access", 0 )
108 set_category( CAT_SOUT )
109 set_subcategory( SUBCAT_SOUT_ACO )
110 add_integer( SOUT_CFG_PREFIX "seglen", 10, SEGLEN_TEXT, SEGLEN_LONGTEXT, false )
111 add_integer( SOUT_CFG_PREFIX "numsegs", 0, NUMSEGS_TEXT, NUMSEGS_LONGTEXT, false )
112 add_bool( SOUT_CFG_PREFIX "splitanywhere", false,
113 SPLITANYWHERE_TEXT, SPLITANYWHERE_LONGTEXT, true )
114 add_bool( SOUT_CFG_PREFIX "delsegs", true,
115 DELSEGS_TEXT, DELSEGS_LONGTEXT, true )
116 add_bool( SOUT_CFG_PREFIX "ratecontrol", false,
117 RATECONTROL_TEXT, RATECONTROL_TEXT, true )
118 add_bool( SOUT_CFG_PREFIX "caching", false,
119 NOCACHE_TEXT, NOCACHE_LONGTEXT, true )
120 add_bool( SOUT_CFG_PREFIX "generate-iv", false,
121 RANDOMIV_TEXT, RANDOMIV_LONGTEXT, true )
122 add_string( SOUT_CFG_PREFIX "index", NULL,
123 INDEX_TEXT, INDEX_LONGTEXT, false )
124 add_string( SOUT_CFG_PREFIX "index-url", NULL,
125 INDEXURL_TEXT, INDEXURL_LONGTEXT, false )
126 add_string( SOUT_CFG_PREFIX "key-uri", NULL,
127 KEYURI_TEXT, KEYURI_TEXT, true )
128 add_loadfile( SOUT_CFG_PREFIX "key-file", NULL,
129 KEYFILE_TEXT, KEYFILE_LONGTEXT, true )
130 set_callbacks( Open, Close )
134 /*****************************************************************************
135 * Exported prototypes
136 *****************************************************************************/
137 static const char *const ppsz_sout_options[] = {
152 static ssize_t Write( sout_access_out_t *, block_t * );
153 static int Seek ( sout_access_out_t *, off_t );
154 static int Control( sout_access_out_t *, int, va_list );
156 struct sout_access_out_sys_t
158 char *psz_cursegPath;
166 block_t *block_buffer;
172 bool b_splitanywhere;
176 gcry_cipher_hd_t aes_ctx;
178 uint8_t stuffing_bytes[16];
179 ssize_t stuffing_size;
182 static int CryptSetup( sout_access_out_t *p_access );
183 /*****************************************************************************
184 * Open: open the file
185 *****************************************************************************/
186 static int Open( vlc_object_t *p_this )
188 sout_access_out_t *p_access = (sout_access_out_t*)p_this;
189 sout_access_out_sys_t *p_sys;
192 config_ChainParse( p_access, SOUT_CFG_PREFIX, ppsz_sout_options, p_access->p_cfg );
194 if( !p_access->psz_path )
196 msg_Err( p_access, "no file name specified" );
200 if( unlikely( !( p_sys = malloc ( sizeof( *p_sys ) ) ) ) )
203 p_sys->i_seglen = var_GetInteger( p_access, SOUT_CFG_PREFIX "seglen" );
204 /* Try to get within asked segment length */
205 p_sys->i_seglenm = CLOCK_FREQ * p_sys->i_seglen;
206 p_sys->block_buffer = NULL;
208 p_sys->i_numsegs = var_GetInteger( p_access, SOUT_CFG_PREFIX "numsegs" );
209 p_sys->b_splitanywhere = var_GetBool( p_access, SOUT_CFG_PREFIX "splitanywhere" );
210 p_sys->b_delsegs = var_GetBool( p_access, SOUT_CFG_PREFIX "delsegs" );
211 p_sys->b_ratecontrol = var_GetBool( p_access, SOUT_CFG_PREFIX "ratecontrol") ;
212 p_sys->b_caching = var_GetBool( p_access, SOUT_CFG_PREFIX "caching") ;
213 p_sys->b_generate_iv = var_GetBool( p_access, SOUT_CFG_PREFIX "generate-iv") ;
215 p_sys->stuffing_size = 0;
217 /* 5 elements is from harrison-stetson algorithm to start from some number
218 * if we don't have numsegs defined
220 p_sys->i_seglens = 5;
221 if( p_sys->i_numsegs )
222 p_sys->i_seglens = p_sys->i_numsegs+1;
223 p_sys->p_seglens = malloc( sizeof(float) * p_sys->i_seglens );
224 if( unlikely( !p_sys->p_seglens ) )
230 p_sys->psz_indexPath = NULL;
231 psz_idx = var_GetNonEmptyString( p_access, SOUT_CFG_PREFIX "index" );
235 psz_tmp = str_format_time( psz_idx );
239 free( p_sys->p_seglens );
243 path_sanitize( psz_tmp );
244 p_sys->psz_indexPath = psz_tmp;
245 vlc_unlink( p_sys->psz_indexPath );
248 p_sys->psz_indexUrl = var_GetNonEmptyString( p_access, SOUT_CFG_PREFIX "index-url" );
250 p_access->p_sys = p_sys;
252 if( CryptSetup( p_access ) < 0 )
254 free( p_sys->psz_indexUrl );
255 free( p_sys->psz_indexPath );
256 free( p_sys->p_seglens );
258 msg_Err( p_access, "Encryption init failed" );
262 p_sys->i_handle = -1;
263 p_sys->i_segment = 0;
264 p_sys->psz_cursegPath = NULL;
266 p_access->pf_write = Write;
267 p_access->pf_seek = Seek;
268 p_access->pf_control = Control;
273 /************************************************************************
274 * CryptSetup: Initialize encryption
275 ************************************************************************/
276 static int CryptSetup( sout_access_out_t *p_access )
278 sout_access_out_sys_t *p_sys = p_access->p_sys;
281 p_sys->key_uri = var_GetNonEmptyString( p_access, SOUT_CFG_PREFIX "key-uri" );
282 if( !p_sys->key_uri ) /*No key uri, assume no encryption wanted*/
284 msg_Dbg( p_access, "No key uri, no encryption");
289 /*Setup encryption cipher*/
290 gcry_error_t err = gcry_cipher_open( &p_sys->aes_ctx, GCRY_CIPHER_AES,
291 GCRY_CIPHER_MODE_CBC, 0 );
294 msg_Err( p_access, "Openin AES Cipher failed: %s", gpg_strerror(err));
298 char *keyfile = var_InheritString( p_access, SOUT_CFG_PREFIX "key-file" );
299 if( unlikely(keyfile == NULL) )
301 msg_Err( p_access, "No key-file, no encryption" );
305 int keyfd = vlc_open( keyfile, O_RDONLY | O_NONBLOCK );
306 if( unlikely( keyfd == -1 ) )
308 msg_Err( p_access, "Unable to open keyfile %s: %m", keyfile );
314 ssize_t keylen = read( keyfd, key, 16 );
319 msg_Err( p_access, "No key at least 16 octects (you provided %zd), no encryption", keylen );
323 err = gcry_cipher_setkey( p_sys->aes_ctx, key, 16 );
326 msg_Err(p_access, "Setting AES key failed: %s", gpg_strerror(err));
327 gcry_cipher_close( p_sys->aes_ctx);
331 if( p_sys->b_generate_iv )
332 vlc_rand_bytes( p_sys->aes_ivs, sizeof(uint8_t)*16);
337 /************************************************************************
338 * CryptKey: Set encryption IV to current segment number
339 ************************************************************************/
340 static int CryptKey( sout_access_out_t *p_access, uint32_t i_segment )
342 sout_access_out_sys_t *p_sys = p_access->p_sys;
344 if( !p_sys->b_generate_iv )
346 /* Use segment number as IV if randomIV isn't selected*/
347 memset( p_sys->aes_ivs, 0, 16 * sizeof(uint8_t));
348 p_sys->aes_ivs[15] = i_segment & 0xff;
349 p_sys->aes_ivs[14] = (i_segment >> 8 ) & 0xff;
350 p_sys->aes_ivs[13] = (i_segment >> 16 ) & 0xff;
351 p_sys->aes_ivs[12] = (i_segment >> 24 ) & 0xff;
354 gcry_error_t err = gcry_cipher_setiv( p_sys->aes_ctx,
358 msg_Err(p_access, "Setting AES IVs failed: %s", gpg_strerror(err) );
359 gcry_cipher_close( p_sys->aes_ctx);
366 #define SEG_NUMBER_PLACEHOLDER "#"
367 /*****************************************************************************
368 * formatSegmentPath: create segment path name based on seg #
369 *****************************************************************************/
370 static char *formatSegmentPath( char *psz_path, uint32_t i_seg, bool b_sanitize )
373 char *psz_firstNumSign;
375 if ( ! ( psz_result = str_format_time( psz_path ) ) )
378 psz_firstNumSign = psz_result + strcspn( psz_result, SEG_NUMBER_PLACEHOLDER );
379 if ( *psz_firstNumSign )
382 int i_cnt = strspn( psz_firstNumSign, SEG_NUMBER_PLACEHOLDER );
385 *psz_firstNumSign = '\0';
386 ret = asprintf( &psz_newResult, "%s%0*d%s", psz_result, i_cnt, i_seg, psz_firstNumSign + i_cnt );
390 psz_result = psz_newResult;
394 path_sanitize( psz_result );
399 /************************************************************************
400 * updateIndexAndDel: If necessary, update index file & delete old segments
401 ************************************************************************/
402 static int updateIndexAndDel( sout_access_out_t *p_access, sout_access_out_sys_t *p_sys, bool b_isend )
407 if ( p_sys->i_numsegs == 0 || p_sys->i_segment < p_sys->i_numsegs )
411 if( p_sys->i_segment >= (p_sys->i_seglens-1) )
413 p_sys->i_seglens <<= 1;
414 msg_Dbg( p_access, "Segment amount %u", p_sys->i_seglens );
415 p_sys->p_seglens = realloc( p_sys->p_seglens, sizeof(float) * p_sys->i_seglens );
416 if( unlikely( !p_sys->p_seglens ) )
421 i_firstseg = ( p_sys->i_segment - p_sys->i_numsegs ) + 1;
423 // First update index
424 if ( p_sys->psz_indexPath )
429 if ( asprintf( &psz_idxTmp, "%s.tmp", p_sys->psz_indexPath ) < 0)
432 fp = vlc_fopen( psz_idxTmp, "wt");
435 msg_Err( p_access, "cannot open index file `%s'", psz_idxTmp );
440 if ( fprintf( fp, "#EXTM3U\n#EXT-X-TARGETDURATION:%zu\n#EXT-X-VERSION:3\n#EXT-X-ALLOW-CACHE:%s"
441 "%s\n#EXT-X-MEDIA-SEQUENCE:%"PRIu32"\n", p_sys->i_seglen,
442 p_sys->b_caching ? "YES" : "NO",
443 p_sys->i_numsegs > 0 ? "" : b_isend ? "\n#EXT-X-PLAYLIST-TYPE:VOD" : "\n#EXT-X-PLAYLIST-TYPE:EVENT",
454 if( p_sys->b_generate_iv )
456 unsigned long long iv_hi = 0, iv_lo = 0;
457 for( unsigned short i = 0; i < 8; i++ )
459 iv_hi |= p_sys->aes_ivs[i] & 0xff;
461 iv_lo |= p_sys->aes_ivs[8+i] & 0xff;
464 ret = fprintf( fp, "#EXT-X-KEY:METHOD=AES-128,URI=\"%s\",IV=0X%16.16llx%16.16llx\n",
465 p_sys->key_uri, iv_hi, iv_lo );
468 ret = fprintf( fp, "#EXT-X-KEY:METHOD=AES-128,URI=\"%s\"\n", p_sys->key_uri );
478 char *psz_idxFormat = p_sys->psz_indexUrl ? p_sys->psz_indexUrl : p_access->psz_path;
479 for ( uint32_t i = i_firstseg; i <= p_sys->i_segment; i++ )
482 char *psz_duration = NULL;
483 if ( ! ( psz_name = formatSegmentPath( psz_idxFormat, i, false ) ) )
489 if( ! ( us_asprintf( &psz_duration, "%.2f", p_sys->p_seglens[i % p_sys->i_seglens ], psz_name ) ) )
495 val = fprintf( fp, "#EXTINF:%s,\n%s\n", psz_duration, psz_name );
496 free( psz_duration );
508 if ( fputs ( STR_ENDLIST, fp ) < 0)
518 val = vlc_rename ( psz_idxTmp, p_sys->psz_indexPath);
522 vlc_unlink( psz_idxTmp );
523 msg_Err( p_access, "Error moving LiveHttp index file" );
526 msg_Info( p_access, "LiveHttpIndexComplete: %s" , p_sys->psz_indexPath );
531 // Then take care of deletion
532 if ( p_sys->b_delsegs && i_firstseg > 1 )
534 char *psz_name = formatSegmentPath( p_access->psz_path, i_firstseg-1, true );
537 vlc_unlink( psz_name );
544 /*****************************************************************************
545 * closeCurrentSegment: Close the segment file
546 *****************************************************************************/
547 static void closeCurrentSegment( sout_access_out_t *p_access, sout_access_out_sys_t *p_sys, bool b_isend )
549 if ( p_sys->i_handle >= 0 )
553 size_t pad = 16 - p_sys->stuffing_size;
554 memset(&p_sys->stuffing_bytes[p_sys->stuffing_size], pad, pad);
555 gcry_error_t err = gcry_cipher_encrypt( p_sys->aes_ctx, p_sys->stuffing_bytes, 16, NULL, 0 );
558 msg_Err( p_access, "Couldn't encrypt 16 bytes: %s", gpg_strerror(err) );
560 int ret = write( p_sys->i_handle, p_sys->stuffing_bytes, 16 );
562 msg_Err( p_access, "Couldn't write 16 bytes" );
564 p_sys->stuffing_size = 0;
566 close( p_sys->i_handle );
567 p_sys->i_handle = -1;
568 if ( p_sys->psz_cursegPath )
570 msg_Info( p_access, "LiveHttpSegmentComplete: %s (%"PRIu32")" , p_sys->psz_cursegPath, p_sys->i_segment );
571 free( p_sys->psz_cursegPath );
572 p_sys->psz_cursegPath = 0;
573 updateIndexAndDel( p_access, p_sys, b_isend );
578 /*****************************************************************************
579 * Close: close the target
580 *****************************************************************************/
581 static void Close( vlc_object_t * p_this )
583 sout_access_out_t *p_access = (sout_access_out_t*)p_this;
584 sout_access_out_sys_t *p_sys = p_access->p_sys;
586 msg_Dbg( p_access, "Flushing buffer to last file");
587 bool crypted = false;
588 while( p_sys->block_buffer )
590 if( p_sys->key_uri && !crypted)
592 if( p_sys->stuffing_size )
594 p_sys->block_buffer = block_Realloc( p_sys->block_buffer, p_sys->stuffing_size, p_sys->block_buffer->i_buffer );
595 if( unlikely(!p_sys->block_buffer) )
597 memcpy( p_sys->block_buffer->p_buffer, p_sys->stuffing_bytes, p_sys->stuffing_size );
598 p_sys->stuffing_size = 0;
600 size_t original = p_sys->block_buffer->i_buffer;
601 size_t padded = (original + 15 ) & ~15;
602 size_t pad = padded - original;
605 p_sys->stuffing_size = 16 - pad;
606 p_sys->block_buffer->i_buffer -= p_sys->stuffing_size;
607 memcpy( p_sys->stuffing_bytes, &p_sys->block_buffer->p_buffer[p_sys->block_buffer->i_buffer], p_sys->stuffing_size );
610 gcry_error_t err = gcry_cipher_encrypt( p_sys->aes_ctx,
611 p_sys->block_buffer->p_buffer, p_sys->block_buffer->i_buffer, NULL, 0 );
614 msg_Err( p_access, "Encryption failure: %s ", gpg_strerror(err) );
619 ssize_t val = write( p_sys->i_handle, p_sys->block_buffer->p_buffer, p_sys->block_buffer->i_buffer );
622 if ( errno == EINTR )
624 block_ChainRelease ( p_sys->block_buffer);
627 if( !p_sys->block_buffer->p_next )
629 p_sys->p_seglens[p_sys->i_segment % p_sys->i_seglens ] =
630 (float)( p_sys->block_buffer->i_length / (1000000)) +
631 (float)(p_sys->block_buffer->i_dts - p_sys->i_opendts) / CLOCK_FREQ;
634 if ( (size_t)val >= p_sys->block_buffer->i_buffer )
636 block_t *p_next = p_sys->block_buffer->p_next;
637 block_Release (p_sys->block_buffer);
638 p_sys->block_buffer = p_next;
643 p_sys->block_buffer->p_buffer += val;
644 p_sys->block_buffer->i_buffer -= val;
648 closeCurrentSegment( p_access, p_sys, true );
649 free( p_sys->psz_indexUrl );
650 free( p_sys->psz_indexPath );
651 free( p_sys->p_seglens );
656 gcry_cipher_close( p_sys->aes_ctx );
657 free( p_sys->key_uri );
659 msg_Dbg( p_access, "livehttp access output closed" );
662 static int Control( sout_access_out_t *p_access, int i_query, va_list args )
664 sout_access_out_sys_t *p_sys = p_access->p_sys;
668 case ACCESS_OUT_CONTROLS_PACE:
670 bool *pb = va_arg( args, bool * );
671 *pb = !p_sys->b_ratecontrol;
682 /*****************************************************************************
683 * openNextFile: Open the segment file
684 *****************************************************************************/
685 static ssize_t openNextFile( sout_access_out_t *p_access, sout_access_out_sys_t *p_sys )
689 uint32_t i_newseg = p_sys->i_segment + 1;
691 char *psz_seg = formatSegmentPath( p_access->psz_path, i_newseg, true );
695 fd = vlc_open( psz_seg, O_WRONLY | O_CREAT | O_LARGEFILE |
699 msg_Err( p_access, "cannot open `%s' (%m)", psz_seg );
705 CryptKey( p_access, i_newseg );
706 msg_Dbg( p_access, "Successfully opened livehttp file: %s (%"PRIu32")" , psz_seg, i_newseg );
709 p_sys->psz_cursegPath = psz_seg;
710 p_sys->i_handle = fd;
711 p_sys->i_segment = i_newseg;
715 /*****************************************************************************
716 * Write: standard write on a file descriptor.
717 *****************************************************************************/
718 static ssize_t Write( sout_access_out_t *p_access, block_t *p_buffer )
721 sout_access_out_sys_t *p_sys = p_access->p_sys;
726 if ( ( p_sys->b_splitanywhere || ( p_buffer->i_flags & BLOCK_FLAG_HEADER ) ) )
728 bool crypted = false;
729 block_t *output = p_sys->block_buffer;
730 p_sys->block_buffer = NULL;
733 if( p_sys->i_handle > 0 &&
734 ( p_buffer->i_dts - p_sys->i_opendts +
735 p_buffer->i_length * CLOCK_FREQ / INT64_C(1000000)
736 ) >= p_sys->i_seglenm )
737 closeCurrentSegment( p_access, p_sys, false );
739 if ( p_sys->i_handle < 0 )
741 p_sys->i_opendts = output ? output->i_dts : p_buffer->i_dts;
742 if ( openNextFile( p_access, p_sys ) < 0 )
748 if( p_sys->key_uri && !crypted )
750 if( p_sys->stuffing_size )
752 output = block_Realloc( output, p_sys->stuffing_size, output->i_buffer );
753 if( unlikely(!output ) )
755 memcpy( output->p_buffer, p_sys->stuffing_bytes, p_sys->stuffing_size );
756 p_sys->stuffing_size = 0;
758 size_t original = output->i_buffer;
759 size_t padded = (output->i_buffer + 15 ) & ~15;
760 size_t pad = padded - original;
763 p_sys->stuffing_size = 16-pad;
764 output->i_buffer -= p_sys->stuffing_size;
765 memcpy(p_sys->stuffing_bytes, &output->p_buffer[output->i_buffer], p_sys->stuffing_size);
768 gcry_error_t err = gcry_cipher_encrypt( p_sys->aes_ctx,
769 output->p_buffer, output->i_buffer, NULL, 0 );
772 msg_Err( p_access, "Encryption failure: %s ", gpg_strerror(err) );
778 ssize_t val = write( p_sys->i_handle, output->p_buffer, output->i_buffer );
781 if ( errno == EINTR )
783 block_ChainRelease ( p_buffer );
786 p_sys->p_seglens[p_sys->i_segment % p_sys->i_seglens ] =
787 (float)output->i_length / INT64_C(1000000) +
788 (float)(output->i_dts - p_sys->i_opendts) / CLOCK_FREQ;
790 if ( (size_t)val >= output->i_buffer )
792 block_t *p_next = output->p_next;
793 block_Release (output);
799 output->p_buffer += val;
800 output->i_buffer -= val;
806 p_temp = p_buffer->p_next;
807 p_buffer->p_next = NULL;
808 block_ChainAppend( &p_sys->block_buffer, p_buffer );
815 /*****************************************************************************
816 * Seek: seek to a specific location in a file
817 *****************************************************************************/
818 static int Seek( sout_access_out_t *p_access, off_t i_pos )
821 msg_Err( p_access, "livehttp sout access cannot seek" );