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 #   include <arpa/inet.h>
  46 #endif
  47 #include "charset.h"
  48
  49 /* SAP is always on that port */
  50 #define SAP_PORT 9875
  51
  52 #define DEFAULT_PORT "1234"
  53
  54 #undef EXTRA_DEBUG
  55
  56 /* SAP Specific structures */
  57
  58 /* 100ms */
  59 #define SAP_IDLE ((mtime_t)(0.100*CLOCK_FREQ))
  60 #define SAP_MAX_BUFFER 65534
  61 #define MIN_INTERVAL 2
  62 #define MAX_INTERVAL 300
  63
  64 /* A SAP announce address. For each of these, we run the
  65  * control flow algorithm */
  66 struct sap_address_t
  67 {
  68     char *psz_address;
  69     char psz_machine[NI_MAXNUMERICHOST];
  70     int i_port;
  71     int i_rfd; /* Read socket */
  72     int i_wfd; /* Write socket */
  73
  74     /* Used for flow control */
  75     mtime_t t1;
  76     vlc_bool_t b_enabled;
  77     vlc_bool_t b_ready;
  78     int i_interval;
  79     int i_buff;
  80     int i_limit;
  81 };
  82
  83 /*****************************************************************************
  84  * Local prototypes
  85  *****************************************************************************/
  86 static void RunThread( vlc_object_t *p_this);
  87 static int CalculateRate( sap_handler_t *p_sap, sap_address_t *p_address );
  88 static char *SDPGenerate( sap_handler_t *p_sap,
  89                           const session_descriptor_t *p_session,
  90                           const sap_address_t *p_addr );
  91
  92 static int announce_SendSAPAnnounce( sap_handler_t *p_sap,
  93                                      sap_session_t *p_session );
  94
  95
  96 static int announce_SAPAnnounceAdd( sap_handler_t *p_sap,
  97                              session_descriptor_t *p_session );
  98
  99 static int announce_SAPAnnounceDel( sap_handler_t *p_sap,
 100                              session_descriptor_t *p_session );
 101
 102 #define FREE( p ) if( p ) { free( p ); (p) = NULL; }
 103
 104
 105 /**
 106  * Create the SAP handler
 107  *
 108  * \param p_announce the parent announce_handler
 109  * \return the newly created SAP handler or NULL on error
 110  */
 111 sap_handler_t *announce_SAPHandlerCreate( announce_handler_t *p_announce )
 112 {
 113     sap_handler_t *p_sap;
 114
 115     p_sap = vlc_object_create( p_announce, sizeof( sap_handler_t ) );
 116
 117     if( !p_sap )
 118     {
 119         msg_Err( p_announce, "out of memory" );
 120         return NULL;
 121     }
 122
 123     vlc_mutex_init( p_sap, &p_sap->object_lock );
 124
 125     p_sap->pf_add = announce_SAPAnnounceAdd;
 126     p_sap->pf_del = announce_SAPAnnounceDel;
 127
 128     p_sap->i_sessions = 0;
 129     p_sap->i_addresses = 0;
 130     p_sap->i_current_session = 0;
 131
 132     p_sap->b_control = config_GetInt( p_sap, "sap-flow-control");
 133
 134     if( vlc_thread_create( p_sap, "sap handler", RunThread,
 135                        VLC_THREAD_PRIORITY_LOW, VLC_FALSE ) )
 136     {
 137         msg_Dbg( p_announce, "Unable to spawn SAP handler thread");
 138         free( p_sap );
 139         return NULL;
 140     };
 141     msg_Dbg( p_announce, "thread created, %i sessions", p_sap->i_sessions);
 142     return p_sap;
 143 }
 144
 145 /**
 146  *  Destroy the SAP handler
 147  *  \param p_this the SAP Handler to destroy
 148  *  \return nothing
 149  */
 150 void announce_SAPHandlerDestroy( sap_handler_t *p_sap )
 151 {
 152     int i;
 153
 154     vlc_mutex_destroy( &p_sap->object_lock );
 155
 156     /* Free the remaining sessions */
 157     for( i = 0 ; i< p_sap->i_sessions ; i++)
 158     {
 159         sap_session_t *p_session = p_sap->pp_sessions[i];
 160         FREE( p_session->psz_sdp );
 161         FREE( p_session->psz_data );
 162         REMOVE_ELEM( p_sap->pp_sessions, p_sap->i_sessions , i );
 163         FREE( p_session );
 164     }
 165
 166     /* Free the remaining addresses */
 167     for( i = 0 ; i< p_sap->i_addresses ; i++)
 168     {
 169         sap_address_t *p_address = p_sap->pp_addresses[i];
 170         FREE( p_address->psz_address );
 171         if( p_address->i_rfd > -1 )
 172         {
 173             net_Close( p_address->i_rfd );
 174         }
 175         if( p_address->i_wfd > -1 && p_sap->b_control )
 176         {
 177             net_Close( p_address->i_wfd );
 178         }
 179         REMOVE_ELEM( p_sap->pp_addresses, p_sap->i_addresses, i );
 180         FREE( p_address );
 181     }
 182
 183     /* Free the structure */
 184     vlc_object_destroy( p_sap );
 185 }
 186
 187 /**
 188  * main SAP handler thread
 189  * \param p_this the SAP Handler object
 190  * \return nothing
 191  */
 192 static void RunThread( vlc_object_t *p_this)
 193 {
 194     sap_handler_t *p_sap = (sap_handler_t*)p_this;
 195     sap_session_t *p_session;
 196
 197     while( !p_sap->b_die )
 198     {
 199         int i;
 200
 201         /* If needed, get the rate info */
 202         if( p_sap->b_control == VLC_TRUE )
 203         {
 204             for( i = 0 ; i< p_sap->i_addresses ; i++)
 205             {
 206                 if( p_sap->pp_addresses[i]->b_enabled == VLC_TRUE )
 207                 {
 208                     CalculateRate( p_sap, p_sap->pp_addresses[i] );
 209                 }
 210             }
 211         }
 212
 213         /* Find the session to announce */
 214         vlc_mutex_lock( &p_sap->object_lock );
 215         if( p_sap->i_sessions > p_sap->i_current_session + 1)
 216         {
 217             p_sap->i_current_session++;
 218         }
 219         else if( p_sap->i_sessions > 0)
 220         {
 221             p_sap->i_current_session = 0;
 222         }
 223         else
 224         {
 225             vlc_mutex_unlock( &p_sap->object_lock );
 226             msleep( SAP_IDLE );
 227             continue;
 228         }
 229         p_session = p_sap->pp_sessions[p_sap->i_current_session];
 230         vlc_mutex_unlock( &p_sap->object_lock );
 231
 232         /* And announce it */
 233         if( p_session->p_address->b_enabled == VLC_TRUE &&
 234             p_session->p_address->b_ready == VLC_TRUE )
 235         {
 236             announce_SendSAPAnnounce( p_sap, p_session );
 237         }
 238
 239         msleep( SAP_IDLE );
 240     }
 241 }
 242
 243 /* Add a SAP announce */
 244 static int announce_SAPAnnounceAdd( sap_handler_t *p_sap,
 245                              session_descriptor_t *p_session )
 246 {
 247     int i_header_size, i;
 248     char *psz_head, psz_addr[NI_MAXNUMERICHOST];
 249     vlc_bool_t b_ipv6 = VLC_FALSE;
 250     sap_session_t *p_sap_session;
 251     mtime_t i_hash;
 252     struct addrinfo hints, *res;
 253     struct sockaddr_storage addr;
 254
 255     vlc_mutex_lock( &p_sap->object_lock );
 256
 257     if( p_session->psz_uri == NULL )
 258     {
 259         vlc_mutex_unlock( &p_sap->object_lock );
 260         msg_Err( p_sap, "*FIXME* Unexpected NULL URI for SAP announce" );
 261         msg_Err( p_sap, "This should not happen. VLC needs fixing." );
 262         return VLC_EGENERIC;
 263     }
 264
 265     /* Determine SAP multicast address automatically */
 266     memset( &hints, 0, sizeof( hints ) );
 267     hints.ai_socktype = SOCK_DGRAM;
 268     hints.ai_flags = AI_NUMERICHOST;
 269
 270     i = vlc_getaddrinfo( (vlc_object_t *)p_sap, p_session->psz_uri, 0,
 271                          &hints, &res );
 272     if( i )
 273     {
 274         vlc_mutex_unlock( &p_sap->object_lock );
 275         msg_Err( p_sap, "Invalid URI for SAP announce: %s: %s",
 276                  p_session->psz_uri, vlc_gai_strerror( i ) );
 277         return VLC_EGENERIC;
 278     }
 279
 280     if( (unsigned)res->ai_addrlen > sizeof( addr ) )
 281     {
 282         vlc_mutex_unlock( &p_sap->object_lock );
 283         vlc_freeaddrinfo( res );
 284         msg_Err( p_sap, "Unsupported address family of size %d > %u",
 285                  res->ai_addrlen, sizeof( addr ) );
 286         return VLC_EGENERIC;
 287     }
 288
 289     memcpy( &addr, res->ai_addr, res->ai_addrlen );
 290
 291     switch( addr.ss_family )
 292     {
 293 #if defined (HAVE_INET_PTON) || defined (WIN32)
 294         case AF_INET6:
 295         {
 296             /* See RFC3513 for list of valid IPv6 scopes */
 297             struct in6_addr *a6 = &((struct sockaddr_in6 *)&addr)->sin6_addr;
 298
 299             memcpy( a6->s6_addr + 2, "\x00\x00\x00\x00\x00\x00"
 300                    "\x00\x00\x00\x00\x00\x02\x7f\xfe", 14 );
 301             if( IN6_IS_ADDR_MULTICAST( a6 ) )
 302                  /* force flags to zero, preserve scope */
 303                 a6->s6_addr[1] &= 0xf;
 304             else
 305                 /* Unicast IPv6 - assume global scope */
 306                 memcpy( a6->s6_addr, "\xff\x0e", 2 );
 307
 308             b_ipv6 = VLC_TRUE;
 309             break;
 310         }
 311 #endif
 312
 313         case AF_INET:
 314         {
 315             /* See RFC2365 for IPv4 scopes */
 316             uint32_t ipv4;
 317
 318             ipv4 = ntohl( ((struct sockaddr_in *)&addr)->sin_addr.s_addr );
 319             /* 224.0.0.0/24 => 224.0.0.255 */
 320             if ((ipv4 & 0xffffff00) == 0xe0000000)
 321                 ipv4 =  0xe00000ff;
 322             else
 323             /* 239.255.0.0/16 => 239.255.255.255 */
 324             if ((ipv4 & 0xffff0000) == 0xefff0000)
 325                 ipv4 =  0xefffffff;
 326             else
 327             /* 239.192.0.0/14 => 239.195.255.255 */
 328             if ((ipv4 & 0xfffc0000) == 0xefc00000)
 329                 ipv4 =  0xefc3ffff;
 330             else
 331             /* other addresses => 224.2.127.254 */
 332                 ipv4 = 0xe0027ffe;
 333             break;
 334         }
 335
 336         default:
 337             vlc_mutex_unlock( &p_sap->object_lock );
 338             vlc_freeaddrinfo( res );
 339             msg_Err( p_sap, "Address family %d not supported by SAP",
 340                      addr.ss_family );
 341             return VLC_EGENERIC;
 342     }
 343
 344     i = vlc_getnameinfo( (struct sockaddr *)&addr, res->ai_addrlen,
 345                          psz_addr, sizeof( psz_addr ), NULL, NI_NUMERICHOST );
 346     vlc_freeaddrinfo( res );
 347
 348     if( i )
 349     {
 350         vlc_mutex_unlock( &p_sap->object_lock );
 351         msg_Err( p_sap, "%s", vlc_gai_strerror( i ) );
 352         return VLC_EGENERIC;
 353     }
 354
 355     msg_Dbg( p_sap, "using SAP address: %s", psz_addr);
 356
 357     /* XXX: Check for dupes */
 358     p_sap_session = (sap_session_t*)malloc(sizeof(sap_session_t));
 359     p_sap_session->p_address = NULL;
 360
 361     /* Add the address to the buffer */
 362     for( i = 0; i < p_sap->i_addresses; i++)
 363     {
 364         if( !strcmp( psz_addr, p_sap->pp_addresses[i]->psz_address ) )
 365         {
 366             p_sap_session->p_address = p_sap->pp_addresses[i];
 367             break;
 368         }
 369     }
 370
 371     if( p_sap_session->p_address == NULL )
 372     {
 373         sap_address_t *p_address = (sap_address_t *)
 374                                     malloc( sizeof(sap_address_t) );
 375         if( !p_address )
 376         {
 377             msg_Err( p_sap, "out of memory" );
 378             return VLC_ENOMEM;
 379         }
 380         p_address->psz_address = strdup( psz_addr );
 381         p_address->i_port  =  9875;
 382         p_address->i_wfd = net_OpenUDP( p_sap, "", 0, psz_addr,
 383                                         p_address->i_port );
 384         if( p_address->i_wfd != -1 )
 385         {
 386             char *ptr;
 387
 388             net_StopRecv( p_address->i_wfd );
 389             net_GetSockAddress( p_address->i_wfd, p_address->psz_machine,
 390                                 NULL );
 391
 392             /* removes scope if present */
 393             ptr = strchr( p_address->psz_machine, '%' );
 394             if( ptr != NULL )
 395                 *ptr = '\0';
 396         }
 397
 398         if( p_sap->b_control == VLC_TRUE )
 399         {
 400             p_address->i_rfd = net_OpenUDP( p_sap, psz_addr,
 401                                             p_address->i_port, "", 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
 433     /* Build the SAP Headers */
 434     i_header_size = ( b_ipv6 ? 16 : 4 ) + 20;
 435     psz_head = (char *) malloc( i_header_size * sizeof( char ) );
 436     if( psz_head == NULL )
 437     {
 438         msg_Err( p_sap, "out of memory" );
 439         return VLC_ENOMEM;
 440     }
 441
 442     /* SAPv1, not encrypted, not compressed */
 443     psz_head[0] = b_ipv6 ? 0x30 : 0x20;
 444     psz_head[1] = 0x00; /* No authentification length */
 445
 446     i_hash = mdate();
 447     psz_head[2] = (i_hash & 0xFF00) >> 8; /* Msg id hash */
 448     psz_head[3] = (i_hash & 0xFF);        /* Msg id hash 2 */
 449
 450     inet_pton( b_ipv6 ? AF_INET6 : AF_INET, /* can't fail */
 451                p_sap_session->p_address->psz_machine, psz_head + 4 );
 452
 453     memcpy( psz_head + (b_ipv6 ? 20 : 8), "application/sdp", 15 );
 454
 455     /* If needed, build the SDP */
 456     if( p_session->psz_sdp == NULL )
 457     {
 458         p_session->psz_sdp = SDPGenerate( p_sap, p_session,
 459                                           p_sap_session->p_address );
 460         if( p_session->psz_sdp == NULL )
 461         {
 462             vlc_mutex_unlock( &p_sap->object_lock );
 463             return VLC_ENOMEM;
 464         }
 465     }
 466
 467     p_sap_session->psz_sdp = strdup( p_session->psz_sdp );
 468     p_sap_session->i_last = 0;
 469
 470     psz_head[ i_header_size-1 ] = '\0';
 471     p_sap_session->i_length = i_header_size + strlen( p_sap_session->psz_sdp);
 472
 473     p_sap_session->psz_data = (uint8_t *)malloc( sizeof(char)*
 474                                                  p_sap_session->i_length );
 475
 476     /* Build the final message */
 477     memcpy( p_sap_session->psz_data, psz_head, i_header_size );
 478     memcpy( p_sap_session->psz_data+i_header_size, p_sap_session->psz_sdp,
 479             strlen( p_sap_session->psz_sdp) );
 480
 481     free( psz_head );
 482
 483     /* Enqueue the announce */
 484     INSERT_ELEM( p_sap->pp_sessions,
 485                  p_sap->i_sessions,
 486                  p_sap->i_sessions,
 487                  p_sap_session );
 488     msg_Dbg( p_sap,"Addresses: %i  Sessions: %i",
 489                    p_sap->i_addresses,p_sap->i_sessions);
 490
 491     /* Remember the SAP session for later deletion */
 492     p_session->p_sap = p_sap_session;
 493
 494     vlc_mutex_unlock( &p_sap->object_lock );
 495
 496     return VLC_SUCCESS;
 497 }
 498
 499 /* Remove a SAP Announce */
 500 static int announce_SAPAnnounceDel( sap_handler_t *p_sap,
 501                              session_descriptor_t *p_session )
 502 {
 503     int i;
 504     vlc_mutex_lock( &p_sap->object_lock );
 505
 506     msg_Dbg( p_sap,"removing SAP announce %p",p_session->p_sap);
 507
 508     /* Dequeue the announce */
 509     for( i = 0; i< p_sap->i_sessions; i++)
 510     {
 511         if( p_session->p_sap == p_sap->pp_sessions[i] )
 512         {
 513             REMOVE_ELEM( p_sap->pp_sessions,
 514                          p_sap->i_sessions,
 515                          i );
 516
 517             FREE( p_session->p_sap->psz_sdp );
 518             FREE( p_session->p_sap->psz_data );
 519             free( p_session->p_sap );
 520             break;
 521         }
 522     }
 523
 524     /* XXX: Dequeue the address too if it is not used anymore
 525      * TODO: - address refcount
 526              - send a SAP deletion packet */
 527
 528     msg_Dbg( p_sap,"%i announces remaining", p_sap->i_sessions );
 529
 530     vlc_mutex_unlock( &p_sap->object_lock );
 531
 532     return VLC_SUCCESS;
 533 }
 534
 535 static int announce_SendSAPAnnounce( sap_handler_t *p_sap,
 536                                      sap_session_t *p_session )
 537 {
 538     int i_ret;
 539
 540     /* This announce has never been sent yet */
 541     if( p_session->i_last == 0 )
 542     {
 543         p_session->i_next = mdate()+ p_session->p_address->i_interval*1000000;
 544         p_session->i_last = 1;
 545         return VLC_SUCCESS;
 546     }
 547
 548     if( p_session->i_next < mdate() )
 549     {
 550 #ifdef EXTRA_DEBUG
 551         msg_Dbg( p_sap, "Sending announce");
 552 #endif
 553         i_ret = net_Write( p_sap, p_session->p_address->i_wfd, NULL,
 554                            p_session->psz_data,
 555                            p_session->i_length );
 556         if( i_ret != (int)p_session->i_length )
 557         {
 558             msg_Warn( p_sap, "SAP send failed on address %s (%i %i)",
 559                    p_session->p_address->psz_address,
 560                    i_ret, p_session->i_length );
 561         }
 562         p_session->i_last = p_session->i_next;
 563         p_session->i_next = p_session->i_last
 564                             + p_session->p_address->i_interval*1000000;
 565     }
 566     else
 567     {
 568         return VLC_SUCCESS;
 569     }
 570     return VLC_SUCCESS;
 571 }
 572
 573 static char *SDPGenerate( sap_handler_t *p_sap,
 574                           const session_descriptor_t *p_session,
 575                           const sap_address_t *p_addr )
 576 {
 577     int64_t i_sdp_id = mdate();
 578     int     i_sdp_version = 1 + p_sap->i_sessions + (rand()&0xfff);
 579     char *psz_group, *psz_name, psz_uribuf[NI_MAXNUMERICHOST], *psz_uri,
 580          *psz_sdp;
 581     char ipv;
 582
 583     psz_group = p_session->psz_group;
 584     psz_name = p_session->psz_name;
 585
 586     /* FIXME: really check that psz_uri is a real IP address
 587      * FIXME: make a common function to obtain a canonical IP address */
 588     ipv = ( strchr( p_session->psz_uri, ':' )  != NULL) ? '6' : '4';
 589     if( *p_session->psz_uri == '[' )
 590     {
 591         char *ptr;
 592
 593         strncpy( psz_uribuf, p_session->psz_uri + 1, sizeof( psz_uribuf ) );
 594         psz_uribuf[sizeof( psz_uribuf ) - 1] = '\0';
 595         ptr = strchr( psz_uribuf, '%' );
 596         if( ptr != NULL)
 597             *ptr = '\0';
 598         ptr = strchr( psz_uribuf, ']' );
 599         if( ptr != NULL)
 600             *ptr = '\0';
 601         psz_uri = psz_uribuf;
 602     }
 603     else
 604         psz_uri = p_session->psz_uri;
 605
 606     /* see the lists in modules/stream_out/rtp.c for compliance stuff */
 607     if( asprintf( &psz_sdp,
 608                             "v=0\r\n"
 609                             "o=- "I64Fd" %d IN IP%c %s\r\n"
 610                             "s=%s\r\n"
 611                             "t=0 0\r\n"
 612                             "c=IN IP%c %s/%d\r\n"
 613                             "m=video %d udp %d\r\n"
 614                             "a=tool:"PACKAGE_STRING"\r\n"
 615                             "a=type:broadcast\r\n"
 616                             "%s%s%s",
 617                             i_sdp_id, i_sdp_version,
 618                             ipv, p_addr->psz_machine,
 619                             psz_name, ipv,
 620                             psz_uri, p_session->i_ttl,
 621                             p_session->i_port, p_session->i_payload,
 622                             psz_group ? "a=x-plgroup:" : "",
 623                             psz_group ?: "", psz_group ? "\r\n" : "" ) == -1 )
 624         return NULL;
 625
 626     msg_Dbg( p_sap, "Generated SDP (%i bytes):\n%s", strlen(psz_sdp),
 627              psz_sdp );
 628     return psz_sdp;
 629 }
 630
 631 static int CalculateRate( sap_handler_t *p_sap, sap_address_t *p_address )
 632 {
 633     int i_read;
 634     uint8_t buffer[SAP_MAX_BUFFER];
 635     int i_tot = 0;
 636     mtime_t i_temp;
 637     int i_rate;
 638
 639     if( p_address->t1 == 0 )
 640     {
 641         p_address->t1 = mdate();
 642         return VLC_SUCCESS;
 643     }
 644     do
 645     {
 646         /* Might be too slow if we have huge data */
 647         i_read = net_ReadNonBlock( p_sap, p_address->i_rfd, NULL, buffer,
 648                                    SAP_MAX_BUFFER, 0 );
 649         i_tot += i_read;
 650     } while( i_read > 0 && i_tot < SAP_MAX_BUFFER );
 651
 652     i_temp = mdate();
 653
 654     /* We calculate the rate every 5 seconds */
 655     if( i_temp - p_address->t1 < 5000000 )
 656     {
 657         p_address->i_buff += i_tot;
 658         return VLC_SUCCESS;
 659     }
 660
 661     /* Bits/second */
 662     i_rate = (int)(8*1000000*((mtime_t)p_address->i_buff + (mtime_t)i_tot ) /
 663                         (i_temp - p_address->t1 ));
 664
 665     p_address->i_limit = 10000;
 666
 667     p_address->i_interval = ((1000*i_rate / p_address->i_limit) *
 668                             (MAX_INTERVAL - MIN_INTERVAL))/1000 + MIN_INTERVAL;
 669
 670     if( p_address->i_interval > MAX_INTERVAL || p_address->i_interval < 0 )
 671     {
 672         p_address->i_interval = MAX_INTERVAL;
 673     }
 674 #ifdef EXTRA_DEBUG
 675     msg_Dbg( p_sap,"%s:%i : Rate=%i, Interval = %i s",
 676                     p_address->psz_address,p_address->i_port,
 677                     i_rate,
 678                     p_address->i_interval );
 679 #endif
 680
 681     p_address->b_ready = VLC_TRUE;
 682
 683     p_address->t1 = i_temp;
 684     p_address->i_buff = 0;
 685
 686     return VLC_SUCCESS;
 687 }