git.sesse.net Git - vlc/blob - src/stream_output/sap.c

   1 /*****************************************************************************
   2  * sap.c : SAP announce handler
   3  *****************************************************************************
   4  * Copyright (C) 2002-2005 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Clément Stenac <zorglub@videolan.org>
   8  *          Rémi Denis-Courmont <rem # videolan.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  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 General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28 #include <stdlib.h>                                                /* free() */
  29 #include <stdio.h>                                              /* sprintf() */
  30 #include <string.h>                                            /* strerror() */
  31 #include <ctype.h>                                  /* tolower(), isxdigit() */
  32
  33 #include <vlc/vlc.h>
  34 #include <vlc/sout.h>
  35
  36 #include "network.h"
  37 #if defined( WIN32 ) || defined( UNDER_CE )
  38 #   if defined(UNDER_CE) && defined(sockaddr_storage)
  39 #       undef sockaddr_storage
  40 #   endif
  41 #   include <winsock2.h>
  42 #   include <ws2tcpip.h>
  43 #else
  44 #   include <netdb.h>
  45 #endif
  46 #include "charset.h"
  47
  48 /* SAP is always on that port */
  49 #define SAP_PORT 9875
  50
  51 #define DEFAULT_PORT "1234"
  52
  53 #undef EXTRA_DEBUG
  54
  55 /* SAP Specific structures */
  56
  57 /* 100ms */
  58 #define SAP_IDLE ((mtime_t)(0.100*CLOCK_FREQ))
  59 #define SAP_MAX_BUFFER 65534
  60 #define MIN_INTERVAL 2
  61 #define MAX_INTERVAL 300
  62
  63 /* A SAP announce address. For each of these, we run the
  64  * control flow algorithm */
  65 struct sap_address_t
  66 {
  67     char *psz_address;
  68     int i_port;
  69     int i_rfd; /* Read socket */
  70     int i_wfd; /* Write socket */
  71
  72     /* Used for flow control */
  73     mtime_t t1;
  74     vlc_bool_t b_enabled;
  75     vlc_bool_t b_ready;
  76     int i_interval;
  77     int i_buff;
  78     int i_limit;
  79 };
  80
  81 /*****************************************************************************
  82  * Local prototypes
  83  *****************************************************************************/
  84 static void RunThread( vlc_object_t *p_this);
  85 static int CalculateRate( sap_handler_t *p_sap, sap_address_t *p_address );
  86 static int SDPGenerate( sap_handler_t *p_sap, session_descriptor_t *p_session );
  87
  88 static int announce_SendSAPAnnounce( sap_handler_t *p_sap,
  89                                      sap_session_t *p_session );
  90
  91
  92 static int announce_SAPAnnounceAdd( sap_handler_t *p_sap,
  93                              session_descriptor_t *p_session,
  94                              announce_method_t *p_method );
  95
  96 static int announce_SAPAnnounceDel( sap_handler_t *p_sap,
  97                              session_descriptor_t *p_session );
  98 static char *convert_to_utf8( struct sap_handler_t *p_this, char *psz_local );
  99
 100 #define FREE( p ) if( p ) { free( p ); (p) = NULL; }
 101
 102
 103 /**
 104  * Create the SAP handler
 105  *
 106  * \param p_announce the parent announce_handler
 107  * \return the newly created SAP handler or NULL on error
 108  */
 109 sap_handler_t *announce_SAPHandlerCreate( announce_handler_t *p_announce )
 110 {
 111     sap_handler_t *p_sap;
 112     char *psz_charset;
 113
 114     p_sap = vlc_object_create( p_announce, sizeof( sap_handler_t ) );
 115
 116     if( !p_sap )
 117     {
 118         msg_Err( p_announce, "out of memory" );
 119         return NULL;
 120     }
 121
 122     vlc_mutex_init( p_sap, &p_sap->object_lock );
 123
 124     vlc_current_charset( &psz_charset );
 125     p_sap->iconvHandle = vlc_iconv_open( "UTF-8", psz_charset );
 126     free( psz_charset );
 127     if( p_sap->iconvHandle == (vlc_iconv_t)(-1) )
 128     {
 129         msg_Warn( p_sap, "Unable to do requested conversion" );
 130     }
 131
 132     p_sap->pf_add = announce_SAPAnnounceAdd;
 133     p_sap->pf_del = announce_SAPAnnounceDel;
 134
 135     p_sap->i_sessions = 0;
 136     p_sap->i_addresses = 0;
 137     p_sap->i_current_session = 0;
 138
 139     p_sap->b_control = config_GetInt( p_sap, "sap-flow-control");
 140
 141     if( vlc_thread_create( p_sap, "sap handler", RunThread,
 142                        VLC_THREAD_PRIORITY_LOW, VLC_FALSE ) )
 143     {
 144         msg_Dbg( p_announce, "Unable to spawn SAP handler thread");
 145         free( p_sap );
 146         return NULL;
 147     };
 148     msg_Dbg( p_announce, "thread created, %i sessions", p_sap->i_sessions);
 149     return p_sap;
 150 }
 151
 152 /**
 153  *  Destroy the SAP handler
 154  *  \param p_this the SAP Handler to destroy
 155  *  \return nothing
 156  */
 157 void announce_SAPHandlerDestroy( sap_handler_t *p_sap )
 158 {
 159     int i;
 160
 161     vlc_mutex_destroy( &p_sap->object_lock );
 162
 163     /* Free the remaining sessions */
 164     for( i = 0 ; i< p_sap->i_sessions ; i++)
 165     {
 166         sap_session_t *p_session = p_sap->pp_sessions[i];
 167         FREE( p_session->psz_sdp );
 168         FREE( p_session->psz_data );
 169         REMOVE_ELEM( p_sap->pp_sessions, p_sap->i_sessions , i );
 170         FREE( p_session );
 171     }
 172
 173     /* Free the remaining addresses */
 174     for( i = 0 ; i< p_sap->i_addresses ; i++)
 175     {
 176         sap_address_t *p_address = p_sap->pp_addresses[i];
 177         FREE( p_address->psz_address );
 178         if( p_address->i_rfd > -1 )
 179         {
 180             net_Close( p_address->i_rfd );
 181         }
 182         if( p_address->i_wfd > -1 && p_sap->b_control )
 183         {
 184             net_Close( p_address->i_wfd );
 185         }
 186         REMOVE_ELEM( p_sap->pp_addresses, p_sap->i_addresses, i );
 187         FREE( p_address );
 188     }
 189
 190     if( p_sap->iconvHandle != (vlc_iconv_t)(-1) )
 191         vlc_iconv_close( p_sap->iconvHandle );
 192
 193     /* Free the structure */
 194     vlc_object_destroy( p_sap );
 195 }
 196
 197 /**
 198  * main SAP handler thread
 199  * \param p_this the SAP Handler object
 200  * \return nothing
 201  */
 202 static void RunThread( vlc_object_t *p_this)
 203 {
 204     sap_handler_t *p_sap = (sap_handler_t*)p_this;
 205     sap_session_t *p_session;
 206
 207     while( !p_sap->b_die )
 208     {
 209         int i;
 210
 211         /* If needed, get the rate info */
 212         if( p_sap->b_control == VLC_TRUE )
 213         {
 214             for( i = 0 ; i< p_sap->i_addresses ; i++)
 215             {
 216                 if( p_sap->pp_addresses[i]->b_enabled == VLC_TRUE )
 217                 {
 218                     CalculateRate( p_sap, p_sap->pp_addresses[i] );
 219                 }
 220             }
 221         }
 222
 223         /* Find the session to announce */
 224         vlc_mutex_lock( &p_sap->object_lock );
 225         if( p_sap->i_sessions > p_sap->i_current_session + 1)
 226         {
 227             p_sap->i_current_session++;
 228         }
 229         else if( p_sap->i_sessions > 0)
 230         {
 231             p_sap->i_current_session = 0;
 232         }
 233         else
 234         {
 235             vlc_mutex_unlock( &p_sap->object_lock );
 236             msleep( SAP_IDLE );
 237             continue;
 238         }
 239         p_session = p_sap->pp_sessions[p_sap->i_current_session];
 240         vlc_mutex_unlock( &p_sap->object_lock );
 241
 242         /* And announce it */
 243         if( p_session->p_address->b_enabled == VLC_TRUE &&
 244             p_session->p_address->b_ready == VLC_TRUE )
 245         {
 246             announce_SendSAPAnnounce( p_sap, p_session );
 247         }
 248
 249         msleep( SAP_IDLE );
 250     }
 251 }
 252
 253 /* Add a SAP announce */
 254 static int announce_SAPAnnounceAdd( sap_handler_t *p_sap,
 255                              session_descriptor_t *p_session,
 256                              announce_method_t *p_method )
 257 {
 258     int i;
 259     char *psz_type = "application/sdp";
 260     int i_header_size;
 261     char *psz_head;
 262     vlc_bool_t b_found = VLC_FALSE, b_ipv6 = VLC_FALSE;
 263     sap_session_t *p_sap_session;
 264     mtime_t i_hash;
 265
 266     vlc_mutex_lock( &p_sap->object_lock );
 267
 268     /* If needed, build the SDP */
 269     if( !p_session->psz_sdp )
 270     {
 271         if ( SDPGenerate( p_sap, p_session ) != VLC_SUCCESS )
 272         {
 273             vlc_mutex_unlock( &p_sap->object_lock );
 274             return VLC_EGENERIC;
 275         }
 276     }
 277
 278     if( p_method->psz_address == NULL )
 279     {
 280         /* Determine SAP multicast address automatically */
 281         char psz_buf[NI_MAXNUMERICHOST], *ptr;
 282         const char *psz_addr;
 283         struct addrinfo hints, *res;
 284
 285         if( p_session->psz_uri == NULL )
 286         {
 287             msg_Err( p_sap, "*FIXME* Unexpected NULL URI for SAP announce" );
 288             msg_Err( p_sap, "This should not happen. VLC needs fixing." );
 289             vlc_mutex_unlock( &p_sap->object_lock );
 290             return VLC_EGENERIC;
 291         }
 292
 293         /* Canonicalize IP address (e.g. 224.00.010.1 => 224.0.10.1) */
 294         memset( &hints, 0, sizeof( hints ) );
 295         hints.ai_socktype = SOCK_DGRAM;
 296         hints.ai_flags = AI_NUMERICHOST;
 297
 298         i = vlc_getaddrinfo( (vlc_object_t *)p_sap, p_session->psz_uri, 0,
 299                              &hints, &res );
 300         if( i == 0 )
 301         {
 302             i = vlc_getnameinfo( res->ai_addr, res->ai_addrlen, psz_buf,
 303                                  sizeof( psz_buf ), NULL, NI_NUMERICHOST );
 304             vlc_freeaddrinfo( res );
 305         }
 306
 307         if( i )
 308         {
 309             msg_Err( p_sap, "Invalid URI for SAP announce : %s : %s",
 310                      p_session->psz_uri, vlc_gai_strerror( i ) );
 311             vlc_mutex_unlock( &p_sap->object_lock );
 312             return VLC_EGENERIC;
 313         }
 314
 315         /* Remove interface specification if present */
 316         ptr = strchr( psz_buf, '%' );
 317         if( ptr != NULL )
 318             *ptr = '\0';
 319
 320         if( strchr( psz_buf, ':' ) != NULL )
 321         {
 322             b_ipv6 = VLC_TRUE;
 323
 324             /* See RFC3513 for list of valid IPv6 scopes */
 325             if( ( tolower( psz_buf[0] ) == 'f' )
 326              && ( tolower( psz_buf[1] ) == 'f' )
 327              && isxdigit( psz_buf[2] ) && isxdigit( psz_buf[3] ) )
 328             {
 329                 /* Multicast IPv6 */
 330                 psz_buf[2] = '0'; /* force flags to zero */
 331                 /* keep scope in psz_addr[3] */
 332                 memcpy( &psz_buf[4], "::2:7ffe", sizeof( "::2:7ffe" ) );
 333                 psz_addr = psz_buf;
 334             }
 335             else
 336                 /* Unicast IPv6 - assume global scope */
 337                 psz_addr = "ff0e::2:7ffe";
 338         }
 339         else
 340         {
 341             /* See RFC2365 for IPv4 scopes */
 342             if( memcmp( psz_buf, "224.0.0.", 8 ) == 0 )
 343                 psz_addr = "224.0.0.255";
 344             else
 345             if( memcmp( psz_buf, "239.255.", 8 ) == 0 )
 346                 psz_addr = "239.255.255.255";
 347             else
 348             if( ( memcmp( psz_buf, "239.19", 6 ) == 0 )
 349              && ( ( psz_buf[6] >= '2' ) && ( psz_buf[6] <= '5' ) ) )
 350                 psz_addr = "239.195.255.255";
 351             else
 352                 /* assume global scope */
 353                 psz_addr = "224.2.127.254";
 354         }
 355
 356         p_method->psz_address = strdup( psz_addr );
 357     }
 358     else
 359         b_ipv6 = (strchr( p_method->psz_address, ':' ) != NULL);
 360
 361     msg_Dbg( p_sap, "using SAP address: %s", p_method->psz_address);
 362
 363     /* XXX: Check for dupes */
 364     p_sap_session = (sap_session_t*)malloc(sizeof(sap_session_t));
 365
 366     p_sap_session->psz_sdp = strdup( p_session->psz_sdp );
 367     p_sap_session->i_last = 0;
 368
 369     /* Add the address to the buffer */
 370     for( i = 0; i< p_sap->i_addresses; i++)
 371     {
 372         if( !strcmp( p_method->psz_address,
 373              p_sap->pp_addresses[i]->psz_address ) )
 374         {
 375             p_sap_session->p_address = p_sap->pp_addresses[i];
 376             b_found = VLC_TRUE;
 377             break;
 378         }
 379     }
 380     if( b_found == VLC_FALSE )
 381     {
 382         sap_address_t *p_address = (sap_address_t *)
 383                                     malloc( sizeof(sap_address_t) );
 384         if( !p_address )
 385         {
 386             msg_Err( p_sap, "out of memory" );
 387             return VLC_ENOMEM;
 388         }
 389         p_address->psz_address = strdup( p_method->psz_address );
 390         p_address->i_port  =  9875;
 391         p_address->i_wfd = net_OpenUDP( p_sap, "", 0,
 392                                         p_address->psz_address,
 393                                         p_address->i_port );
 394         if( p_address->i_wfd != -1 )
 395             net_StopRecv( p_address->i_wfd );
 396
 397         if( p_sap->b_control == VLC_TRUE )
 398         {
 399             p_address->i_rfd = net_OpenUDP( p_sap, p_method->psz_address,
 400                                             p_address->i_port,
 401                                             "", 0 );
 402             if( p_address->i_rfd != -1 )
 403                 net_StopSend( p_address->i_rfd );
 404             p_address->i_buff = 0;
 405             p_address->b_enabled = VLC_TRUE;
 406             p_address->b_ready = VLC_FALSE;
 407             p_address->i_limit = 10000; /* 10000 bps */
 408             p_address->t1 = 0;
 409         }
 410         else
 411         {
 412             p_address->b_enabled = VLC_TRUE;
 413             p_address->b_ready = VLC_TRUE;
 414             p_address->i_interval = config_GetInt( p_sap,"sap-interval");
 415             p_address->i_rfd = -1;
 416         }
 417
 418         if( p_address->i_wfd == -1 || (p_address->i_rfd == -1
 419                                         && p_sap->b_control ) )
 420         {
 421             msg_Warn( p_sap, "disabling address" );
 422             p_address->b_enabled = VLC_FALSE;
 423         }
 424
 425         INSERT_ELEM( p_sap->pp_addresses,
 426                      p_sap->i_addresses,
 427                      p_sap->i_addresses,
 428                      p_address );
 429         p_sap_session->p_address = p_address;
 430     }
 431
 432     /* Build the SAP Headers */
 433     i_header_size = ( b_ipv6 ? 20 : 8 ) + strlen( psz_type ) + 1;
 434     psz_head = (char *) malloc( i_header_size * sizeof( char ) );
 435     if( ! psz_head )
 436     {
 437         msg_Err( p_sap, "out of memory" );
 438         return VLC_ENOMEM;
 439     }
 440
 441     psz_head[0] = 0x20; /* Means SAPv1, IPv4, not encrypted, not compressed */
 442     psz_head[1] = 0x00; /* No authentification length */
 443
 444     i_hash = mdate();
 445     psz_head[2] = (i_hash & 0xFF00) >> 8; /* Msg id hash */
 446     psz_head[3] = (i_hash & 0xFF);        /* Msg id hash 2 */
 447
 448     if( b_ipv6 )
 449     {
 450         /* in_addr_t ip_server = inet_addr( ip ); */
 451         psz_head[0] |= 0x10; /* Set IPv6 */
 452
 453         psz_head[4] = 0x01; /* Source IP  FIXME: we should get the real address */
 454         psz_head[5] = 0x02; /* idem */
 455         psz_head[6] = 0x03; /* idem */
 456         psz_head[7] = 0x04; /* idem */
 457
 458         psz_head[8] = 0x01; /* Source IP  FIXME: we should get the real address */
 459         psz_head[9] = 0x02; /* idem */
 460         psz_head[10] = 0x03; /* idem */
 461         psz_head[11] = 0x04; /* idem */
 462
 463         psz_head[12] = 0x01; /* Source IP  FIXME: we should get the real address */
 464         psz_head[13] = 0x02; /* idem */
 465         psz_head[14] = 0x03; /* idem */
 466         psz_head[15] = 0x04; /* idem */
 467
 468         psz_head[16] = 0x01; /* Source IP  FIXME: we should get the real address */
 469         psz_head[17] = 0x02; /* idem */
 470         psz_head[18] = 0x03; /* idem */
 471         psz_head[19] = 0x04; /* idem */
 472
 473         strncpy( psz_head + 20, psz_type, 15 );
 474     }
 475     else
 476     {
 477         /* in_addr_t ip_server = inet_addr( ip) */
 478         /* Source IP  FIXME: we should get the real address */
 479         psz_head[4] = 0x01; /* ip_server */
 480         psz_head[5] = 0x02; /* ip_server>>8 */
 481         psz_head[6] = 0x03; /* ip_server>>16 */
 482         psz_head[7] = 0x04; /* ip_server>>24 */
 483
 484         strncpy( psz_head + 8, psz_type, 15 );
 485     }
 486
 487     psz_head[ i_header_size-1 ] = '\0';
 488     p_sap_session->i_length = i_header_size + strlen( p_sap_session->psz_sdp);
 489
 490     p_sap_session->psz_data = (uint8_t *)malloc( sizeof(char)*
 491                                                  p_sap_session->i_length );
 492
 493     /* Build the final message */
 494     memcpy( p_sap_session->psz_data, psz_head, i_header_size );
 495     memcpy( p_sap_session->psz_data+i_header_size, p_sap_session->psz_sdp,
 496             strlen( p_sap_session->psz_sdp) );
 497
 498     free( psz_head );
 499
 500     /* Enqueue the announce */
 501     INSERT_ELEM( p_sap->pp_sessions,
 502                  p_sap->i_sessions,
 503                  p_sap->i_sessions,
 504                  p_sap_session );
 505     msg_Dbg( p_sap,"Addresses: %i  Sessions: %i",
 506                    p_sap->i_addresses,p_sap->i_sessions);
 507
 508     /* Remember the SAP session for later deletion */
 509     p_session->p_sap = p_sap_session;
 510
 511     vlc_mutex_unlock( &p_sap->object_lock );
 512
 513     return VLC_SUCCESS;
 514 }
 515
 516 /* Remove a SAP Announce */
 517 static int announce_SAPAnnounceDel( sap_handler_t *p_sap,
 518                              session_descriptor_t *p_session )
 519 {
 520     int i;
 521     vlc_mutex_lock( &p_sap->object_lock );
 522
 523     msg_Dbg( p_sap,"removing SAP announce %p",p_session->p_sap);
 524
 525     /* Dequeue the announce */
 526     for( i = 0; i< p_sap->i_sessions; i++)
 527     {
 528         if( p_session->p_sap == p_sap->pp_sessions[i] )
 529         {
 530             REMOVE_ELEM( p_sap->pp_sessions,
 531                          p_sap->i_sessions,
 532                          i );
 533
 534             FREE( p_session->p_sap->psz_sdp );
 535             FREE( p_session->p_sap->psz_data );
 536             free( p_session->p_sap );
 537             break;
 538         }
 539     }
 540
 541     /* XXX: Dequeue the address too if it is not used anymore
 542      * TODO: - address refcount
 543              - send a SAP deletion packet */
 544
 545     msg_Dbg( p_sap,"%i announces remaining", p_sap->i_sessions );
 546
 547     vlc_mutex_unlock( &p_sap->object_lock );
 548
 549     return VLC_SUCCESS;
 550 }
 551
 552 static int announce_SendSAPAnnounce( sap_handler_t *p_sap,
 553                                      sap_session_t *p_session )
 554 {
 555     int i_ret;
 556
 557     /* This announce has never been sent yet */
 558     if( p_session->i_last == 0 )
 559     {
 560         p_session->i_next = mdate()+ p_session->p_address->i_interval*1000000;
 561         p_session->i_last = 1;
 562         return VLC_SUCCESS;
 563     }
 564
 565     if( p_session->i_next < mdate() )
 566     {
 567 #ifdef EXTRA_DEBUG
 568         msg_Dbg( p_sap, "Sending announce");
 569 #endif
 570         i_ret = net_Write( p_sap, p_session->p_address->i_wfd, NULL,
 571                            p_session->psz_data,
 572                            p_session->i_length );
 573         if( i_ret != p_session->i_length )
 574         {
 575             msg_Warn( p_sap, "SAP send failed on address %s (%i %i)",
 576                    p_session->p_address->psz_address,
 577                    i_ret, p_session->i_length );
 578         }
 579         p_session->i_last = p_session->i_next;
 580         p_session->i_next = p_session->i_last
 581                             + p_session->p_address->i_interval*1000000;
 582     }
 583     else
 584     {
 585         return VLC_SUCCESS;
 586     }
 587     return VLC_SUCCESS;
 588 }
 589
 590 static int SDPGenerate( sap_handler_t *p_sap, session_descriptor_t *p_session )
 591 {
 592     int64_t i_sdp_id = mdate();
 593     int     i_sdp_version = 1 + p_sap->i_sessions + (rand()&0xfff);
 594     char *psz_group, *psz_name, psz_uribuf[NI_MAXNUMERICHOST], *psz_uri;
 595     char ipv;
 596
 597     psz_group = convert_to_utf8( p_sap, p_session->psz_group );
 598     psz_name = convert_to_utf8( p_sap, p_session->psz_name );
 599
 600     /* FIXME: really check that psz_uri is a real IP address
 601      * FIXME: make a common function to obtain a canonical IP address */
 602     ipv = ( strchr( p_session->psz_uri, ':' )  != NULL) ? '6' : '4';
 603     if( *p_session->psz_uri == '[' )
 604     {
 605         char *ptr;
 606
 607         strncpy( psz_uribuf, p_session->psz_uri + 1, sizeof( psz_uribuf ) );
 608         psz_uribuf[sizeof( psz_uribuf ) - 1] = '\0';
 609         ptr = strchr( psz_uribuf, '%' );
 610         if( ptr != NULL)
 611             *ptr = '\0';
 612         ptr = strchr( psz_uribuf, ']' );
 613         if( ptr != NULL)
 614             *ptr = '\0';
 615         psz_uri = psz_uribuf;
 616     }
 617     else
 618         psz_uri = p_session->psz_uri;
 619
 620     /* see the lists in modules/stream_out/rtp.c for compliance stuff */
 621     p_session->psz_sdp = (char *)malloc(
 622                             sizeof("v=0\r\n"
 623                                    "o=- 45383436098 45398  IN IP4 127.0.0.1\r\n" /* FIXME */
 624                                    "s=\r\n"
 625                                    "t=0 0\r\n"
 626                                    "c=IN IP4 /\r\n"
 627                                    "m=video  udp\r\n"
 628                                    "a=tool:"PACKAGE_STRING"\r\n"
 629                                    "a=type:broadcast\r\n")
 630                            + strlen( psz_name )
 631                            + strlen( psz_uri ) + 300
 632                            + ( psz_group ? strlen( psz_group ) : 0 ) );
 633
 634     if( p_session->psz_sdp == NULL || psz_name == NULL )
 635     {
 636         msg_Err( p_sap, "out of memory" );
 637         FREE( psz_name );
 638         FREE( psz_group );
 639         return VLC_ENOMEM;
 640     }
 641
 642     sprintf( p_session->psz_sdp,
 643                             "v=0\r\n"
 644                             "o=- "I64Fd" %d IN IP4 127.0.0.1\r\n"
 645                             "s=%s\r\n"
 646                             "t=0 0\r\n"
 647                             "c=IN IP%c %s/%d\r\n"
 648                             "m=video %d udp %d\r\n"
 649                             "a=tool:"PACKAGE_STRING"\r\n"
 650                             "a=type:broadcast\r\n",
 651                             i_sdp_id, i_sdp_version,
 652                             psz_name, ipv,
 653                             psz_uri, p_session->i_ttl,
 654                             p_session->i_port, p_session->i_payload );
 655     free( psz_name );
 656
 657     if( psz_group )
 658     {
 659         sprintf( p_session->psz_sdp, "%sa=x-plgroup:%s\r\n",
 660                                      p_session->psz_sdp, psz_group );
 661         free( psz_group );
 662     }
 663
 664     msg_Dbg( p_sap, "Generated SDP (%i bytes):\n%s", strlen(p_session->psz_sdp),
 665                     p_session->psz_sdp );
 666     return VLC_SUCCESS;
 667 }
 668
 669 static int CalculateRate( sap_handler_t *p_sap, sap_address_t *p_address )
 670 {
 671     int i_read;
 672     uint8_t buffer[SAP_MAX_BUFFER];
 673     int i_tot = 0;
 674     mtime_t i_temp;
 675     int i_rate;
 676
 677     if( p_address->t1 == 0 )
 678     {
 679         p_address->t1 = mdate();
 680         return VLC_SUCCESS;
 681     }
 682     do
 683     {
 684         /* Might be too slow if we have huge data */
 685         i_read = net_ReadNonBlock( p_sap, p_address->i_rfd, NULL, buffer,
 686                                    SAP_MAX_BUFFER, 0 );
 687         i_tot += i_read;
 688     } while( i_read > 0 && i_tot < SAP_MAX_BUFFER );
 689
 690     i_temp = mdate();
 691
 692     /* We calculate the rate every 5 seconds */
 693     if( i_temp - p_address->t1 < 5000000 )
 694     {
 695         p_address->i_buff += i_tot;
 696         return VLC_SUCCESS;
 697     }
 698
 699     /* Bits/second */
 700     i_rate = (int)(8*1000000*((mtime_t)p_address->i_buff + (mtime_t)i_tot ) /
 701                         (i_temp - p_address->t1 ));
 702
 703     p_address->i_limit = 10000;
 704
 705     p_address->i_interval = ((1000*i_rate / p_address->i_limit) *
 706                             (MAX_INTERVAL - MIN_INTERVAL))/1000 + MIN_INTERVAL;
 707
 708     if( p_address->i_interval > MAX_INTERVAL || p_address->i_interval < 0 )
 709     {
 710         p_address->i_interval = MAX_INTERVAL;
 711     }
 712 #ifdef EXTRA_DEBUG
 713     msg_Dbg( p_sap,"%s:%i : Rate=%i, Interval = %i s",
 714                     p_address->psz_address,p_address->i_port,
 715                     i_rate,
 716                     p_address->i_interval );
 717 #endif
 718
 719     p_address->b_ready = VLC_TRUE;
 720
 721     p_address->t1 = i_temp;
 722     p_address->i_buff = 0;
 723
 724     return VLC_SUCCESS;
 725 }
 726
 727
 728 static char *convert_to_utf8( struct sap_handler_t *p_this, char *psz_local )
 729 {
 730     char *psz_unicode, *psz_in, *psz_out;
 731     size_t ret, i_in, i_out;
 732
 733     if( psz_local == NULL )
 734         return NULL;
 735     if ( p_this->iconvHandle == (vlc_iconv_t)(-1) )
 736         return strdup( psz_local );
 737
 738     psz_in = psz_local;
 739     i_in = strlen( psz_local );
 740
 741     i_out = 6 * i_in;
 742     psz_unicode = malloc( i_out + 1 );
 743     if( psz_unicode == NULL )
 744         return strdup( psz_local );
 745     psz_out = psz_unicode;
 746
 747     ret = vlc_iconv( p_this->iconvHandle,
 748                      &psz_in, &i_in, &psz_out, &i_out);
 749     if( ret == (size_t)(-1) || i_in )
 750     {
 751         msg_Warn( p_this, "Failed to convert \"%s\" to UTF-8", psz_local );
 752         return strdup( psz_local );
 753     }
 754     *psz_out = '\0';
 755     return psz_unicode;
 756 }