* opentracker now drops permissions in correct order and really chroots() if ran as root

* lock passing between add_peer_to_torrent and return_peers_for_torrent is now avoided by providing a more general add_peer_to_torrent_and_return_peers function that can be used with NULL parameters to not return any peers (in sync case)
* in order to keep a fast overview how many torrents opentracker maintains, every mutex_bucket_unlock operation expects an additional integer parameter that tells ot_mutex.c how many torrents have been added or removed. A function mutex_get_torrent_count has been introduced.

1 files changed, 319 insertions, 81 deletions

diff --git a/ot_livesync.c b/ot_livesync.c
index 3cad121..47a371a 100644
--- a/ot_livesync.c
+++ b/ot_livesync.c
@@ -9,59 +9,109 @@
 #include <string.h>
 #include <pthread.h>
 #include <unistd.h>
+#include <stdlib.h>
 
 /* Libowfat */
 #include "socket.h"
 #include "ndelay.h"
+#include "byte.h"
 
 /* Opentracker */
 #include "trackerlogic.h"
 #include "ot_livesync.h"
 #include "ot_accesslist.h"
 #include "ot_stats.h"
+#include "ot_mutex.h"
 
 #ifdef WANT_SYNC_LIVE
 
-char groupip_1[4] = { 224,0,23,42 };
+char groupip_1[4] = { 224,0,23,5 };
 
-#define LIVESYNC_BUFFINSIZE (256*256)
-#define LIVESYNC_BUFFSIZE  1504
-#define LIVESYNC_BUFFWATER (sizeof(ot_peer)+sizeof(ot_hash))
+#define LIVESYNC_INCOMING_BUFFSIZE          (256*256)
 
-#define LIVESYNC_MAXDELAY  15
+#define LIVESYNC_OUTGOING_BUFFSIZE_PEERS     1504
+#define LIVESYNC_OUTGOING_WATERMARK_PEERS   (sizeof(ot_peer)+sizeof(ot_hash))
+
+#ifdef WANT_SYNC_SCRAPE
+#define LIVESYNC_OUTGOING_BUFFSIZE_SCRAPE    1504
+#define LIVESYNC_OUTGOING_WATERMARK_SCRAPE  (sizeof(ot_hash)+sizeof(uint64_t)+sizeof(uint32_t))
+#define LIVESYNC_OUTGOING_MAXPACKETS_SCRAPE  100
+
+#define LIVESYNC_FIRST_BEACON_DELAY          (30*60) /* seconds */
+#define LIVESYNC_BEACON_INTERVAL             60      /* seconds */
+#define LIVESYNC_INQUIRE_THRESH              0.75
+#endif /* WANT_SYNC_SCRAPE */
+
+#define LIVESYNC_MAXDELAY                    15      /* seconds */
+
+enum { OT_SYNC_PEER
+#ifdef WANT_SYNC_SCRAPE
+  , OT_SYNC_SCRAPE_BEACON, OT_SYNC_SCRAPE_INQUIRE, OT_SYNC_SCRAPE_TELL
+#endif
+};
 
 /* Forward declaration */
 static void * livesync_worker( void * args );
 
 /* For outgoing packets */
-static int64 g_livesync_socket_in = -1;
+static int64    g_socket_in = -1;
 
 /* For incoming packets */
-static int64 g_livesync_socket_out = -1;
+static int64    g_socket_out = -1;
+static uint8_t  g_inbuffer[LIVESYNC_INCOMING_BUFFSIZE];
 
-static uint8_t  livesync_inbuffer[LIVESYNC_BUFFINSIZE];
-static uint8_t  livesync_outbuffer_start[ LIVESYNC_BUFFSIZE ];
-static uint8_t *livesync_outbuffer_pos;
-static uint8_t *livesync_outbuffer_highwater = livesync_outbuffer_start + LIVESYNC_BUFFSIZE - LIVESYNC_BUFFWATER;
-static ot_time  livesync_lastpacket_time;
+static uint8_t  g_peerbuffer_start[LIVESYNC_OUTGOING_BUFFSIZE_PEERS];
+static uint8_t *g_peerbuffer_pos;
+static uint8_t *g_peerbuffer_highwater = g_peerbuffer_start + LIVESYNC_OUTGOING_BUFFSIZE_PEERS - LIVESYNC_OUTGOING_WATERMARK_PEERS;
+
+static ot_time  g_next_packet_time;
+
+#ifdef WANT_SYNC_SCRAPE
+/* Live sync scrape buffers, states and timers */
+static ot_time  g_next_beacon_time;
+static ot_time  g_next_inquire_time;
+
+static uint8_t  g_scrapebuffer_start[LIVESYNC_OUTGOING_BUFFSIZE_SCRAPE];
+static uint8_t *g_scrapebuffer_pos;
+static uint8_t *g_scrapebuffer_highwater = g_scrapebuffer_start + LIVESYNC_OUTGOING_BUFFSIZE_SCRAPE - LIVESYNC_OUTGOING_WATERMARK_SCRAPE;
+
+static size_t   g_inquire_remote_count;
+static uint32_t g_inquire_remote_host;
+static int      g_inquire_inprogress;
+static int      g_inquire_bucket;
+#endif /* WANT_SYNC_SCRAPE */
 
 static pthread_t thread_id;
 void livesync_init( ) {
-  if( g_livesync_socket_in == -1 )
+  if( g_socket_in == -1 )
     exerr( "No socket address for live sync specified." );
-  livesync_outbuffer_pos = livesync_outbuffer_start;
-  memmove( livesync_outbuffer_pos, &g_tracker_id, sizeof( g_tracker_id ) );
-  livesync_outbuffer_pos += sizeof( g_tracker_id );
-  livesync_lastpacket_time = g_now_seconds;
+
+  /* Prepare outgoing peers buffer */
+  g_peerbuffer_pos = g_peerbuffer_start;
+  memmove( g_peerbuffer_pos, &g_tracker_id, sizeof( g_tracker_id ) );
+  uint32_pack_big( (char*)g_peerbuffer_pos + sizeof( g_tracker_id ), OT_SYNC_PEER);
+  g_peerbuffer_pos += sizeof( g_tracker_id ) + sizeof( uint32_t);
+
+#ifdef WANT_SYNC_SCRAPE
+  /* Prepare outgoing scrape buffer */
+  g_scrapebuffer_pos = g_scrapebuffer_start;
+  memmove( g_scrapebuffer_pos, &g_tracker_id, sizeof( g_tracker_id ) );
+  uint32_pack_big( (char*)g_scrapebuffer_pos + sizeof( g_tracker_id ), OT_SYNC_SCRAPE_TELL);
+  g_scrapebuffer_pos += sizeof( g_tracker_id ) + sizeof( uint32_t);
+
+  /* Wind up timers for inquires */
+  g_next_beacon_time = g_now_seconds + LIVESYNC_FIRST_BEACON_DELAY;
+#endif /* WANT_SYNC_SCRAPE */
+  g_next_packet_time = g_now_seconds + LIVESYNC_MAXDELAY;
 
   pthread_create( &thread_id, NULL, livesync_worker, NULL );
 }
 
 void livesync_deinit() {
-  if( g_livesync_socket_in != -1 )
-    close( g_livesync_socket_in );
-  if( g_livesync_socket_out != -1 )
-    close( g_livesync_socket_out );
+  if( g_socket_in != -1 )
+    close( g_socket_in );
+  if( g_socket_out != -1 )
+    close( g_socket_out );
 
   pthread_cancel( thread_id );
 }
@@ -69,104 +119,292 @@ void livesync_deinit() {
 void livesync_bind_mcast( char *ip, uint16_t port) {
   char tmpip[4] = {0,0,0,0};
 
-  if( g_livesync_socket_in != -1 )
+  if( g_socket_in != -1 )
     exerr("Error: Livesync listen ip specified twice.");
 
-  if( ( g_livesync_socket_in = socket_udp4( )) < 0)
+  if( ( g_socket_in = socket_udp4( )) < 0)
     exerr("Error: Cant create live sync incoming socket." );
-  ndelay_off(g_livesync_socket_in);
+  ndelay_off(g_socket_in);
 
-  if( socket_bind4_reuse( g_livesync_socket_in, tmpip, port ) == -1 )
+  if( socket_bind4_reuse( g_socket_in, tmpip, port ) == -1 )
     exerr("Error: Cant bind live sync incoming socket." );
 
-  if( socket_mcjoin4( g_livesync_socket_in, groupip_1, ip ) )
+  if( socket_mcjoin4( g_socket_in, groupip_1, ip ) )
     exerr("Error: Cant make live sync incoming socket join mcast group.");
 
-  if( ( g_livesync_socket_out = socket_udp4()) < 0)
+  if( ( g_socket_out = socket_udp4()) < 0)
     exerr("Error: Cant create live sync outgoing socket." );
-  if( socket_bind4_reuse( g_livesync_socket_out, ip, port ) == -1 )
+  if( socket_bind4_reuse( g_socket_out, ip, port ) == -1 )
     exerr("Error: Cant bind live sync outgoing socket." );
 
-  socket_mcttl4(g_livesync_socket_out, 1);
-  socket_mcloop4(g_livesync_socket_out, 0);
+  socket_mcttl4(g_socket_out, 1);
+  socket_mcloop4(g_socket_out, 0);
 }
 
-static void livesync_issuepacket( ) {
-  socket_send4(g_livesync_socket_out, (char*)livesync_outbuffer_start, livesync_outbuffer_pos - livesync_outbuffer_start,
+static void livesync_issue_peersync( ) {
+  socket_send4(g_socket_out, (char*)g_peerbuffer_start, g_peerbuffer_pos - g_peerbuffer_start,
                groupip_1, LIVESYNC_PORT);
-  livesync_outbuffer_pos = livesync_outbuffer_start + sizeof( g_tracker_id );
-  livesync_lastpacket_time = g_now_seconds;
+  g_peerbuffer_pos   = g_peerbuffer_start + sizeof( g_tracker_id ) + sizeof( uint32_t );
+  g_next_packet_time = g_now_seconds + LIVESYNC_MAXDELAY;
 }
 
-/* Inform live sync about whats going on. */
-void livesync_tell( ot_hash * const info_hash, const ot_peer * const peer ) {
-  int i;
-  for(i=0;i<20;i+=4) WRITE32(livesync_outbuffer_pos,i,READ32(info_hash,i));
-  WRITE32(livesync_outbuffer_pos,20,READ32(peer,0));
-  WRITE32(livesync_outbuffer_pos,24,READ32(peer,4));
-  livesync_outbuffer_pos += 28;
-
-  if( livesync_outbuffer_pos >= livesync_outbuffer_highwater )
-    livesync_issuepacket();
+static void livesync_handle_peersync( ssize_t datalen ) {
+  int off = sizeof( g_tracker_id ) + sizeof( uint32_t );
+
+  /* Now basic sanity checks have been done on the live sync packet
+     We might add more testing and logging. */
+  while( off + (ssize_t)sizeof( ot_hash ) + (ssize_t)sizeof( ot_peer ) <= datalen ) {
+    ot_peer *peer = (ot_peer*)(g_inbuffer + off + sizeof(ot_hash));
+    ot_hash *hash = (ot_hash*)(g_inbuffer + off);
+
+    if( !g_opentracker_running ) return;
+
+    if( OT_PEERFLAG(peer) & PEER_FLAG_STOPPED )
+      remove_peer_from_torrent(hash, peer, NULL, FLAG_MCA );
+    else
+      add_peer_to_torrent( hash, peer, FLAG_MCA );
+
+    off += sizeof( ot_hash ) + sizeof( ot_peer );
+  }
+
+  stats_issue_event(EVENT_SYNC, 0, datalen / ((ssize_t)sizeof( ot_hash ) + (ssize_t)sizeof( ot_peer )));
 }
 
+#ifdef WANT_SYNC_SCRAPE
+void livesync_issue_beacon( ) {
+  size_t torrent_count = mutex_get_torrent_count();
+  uint8_t beacon[ sizeof(g_tracker_id) + sizeof(uint32_t) + sizeof( uint64_t ) ];
+
+  memmove( beacon, &g_tracker_id, sizeof( g_tracker_id ) );
+  uint32_pack_big( (char*)beacon + sizeof( g_tracker_id ), OT_SYNC_SCRAPE_BEACON);
+  uint32_pack_big( (char*)beacon + sizeof( g_tracker_id ) +     sizeof(uint32_t), (uint32_t)((uint64_t)(torrent_count)>>32) );
+  uint32_pack_big( (char*)beacon + sizeof( g_tracker_id ) + 2 * sizeof(uint32_t), (uint32_t)torrent_count );
+
+  socket_send4(g_socket_out, (char*)beacon, sizeof(beacon), groupip_1, LIVESYNC_PORT);
+}
+
+void livesync_handle_beacon( ssize_t datalen ) {
+  size_t torrent_count_local, torrent_count_remote;
+  if( datalen != sizeof(g_tracker_id) + sizeof(uint32_t) + sizeof( uint64_t ) )
+    return;
+  torrent_count_local   = mutex_get_torrent_count();
+  torrent_count_remote  = (size_t)(((uint64_t)uint32_read_big((char*)g_inbuffer+sizeof( g_tracker_id ) + sizeof(uint32_t))) << 32);
+  torrent_count_remote |= (size_t)uint32_read_big((char*)g_inbuffer+sizeof( g_tracker_id ) + 2 * sizeof(uint32_t));
+
+  /* Empty tracker is useless */
+  if( !torrent_count_remote ) return;
+
+  if( ((double)torrent_count_local ) / ((double)torrent_count_remote) < LIVESYNC_INQUIRE_THRESH) {
+    if( !g_next_inquire_time ) {
+      g_next_inquire_time    = g_now_seconds + 2 * LIVESYNC_BEACON_INTERVAL;
+      g_inquire_remote_count = 0;
+    }
+
+    if( torrent_count_remote > g_inquire_remote_count ) {
+      g_inquire_remote_count = torrent_count_remote;
+      memmove( &g_inquire_remote_host, g_inbuffer, sizeof( g_tracker_id ) );
+    }
+  }
+}
+
+void livesync_issue_inquire( ) {
+  uint8_t inquire[ sizeof(g_tracker_id) + sizeof(uint32_t) + sizeof(g_tracker_id)];
+
+  memmove( inquire, &g_tracker_id, sizeof( g_tracker_id ) );
+  uint32_pack_big( (char*)inquire + sizeof( g_tracker_id ), OT_SYNC_SCRAPE_INQUIRE);
+  memmove( inquire + sizeof(g_tracker_id) + sizeof(uint32_t), &g_inquire_remote_host, sizeof( g_tracker_id ) );
+
+  socket_send4(g_socket_out, (char*)inquire, sizeof(inquire), groupip_1, LIVESYNC_PORT);
+}
+
+void livesync_handle_inquire( ssize_t datalen ) {
+  if( datalen != sizeof(g_tracker_id) + sizeof(uint32_t) + sizeof(g_tracker_id) )
+    return;
+
+  /* If it isn't us, they're inquiring, ignore inquiry */
+  if( memcmp( &g_tracker_id, g_inbuffer, sizeof( g_tracker_id ) ) )
+    return;
+
+  /* Start scrape tell on next ticker */
+  if( !g_inquire_inprogress ) {
+    g_inquire_inprogress = 1;
+    g_inquire_bucket     = 0;
+  }
+}
+
+void livesync_issue_tell( ) {
+  int packets_to_send = LIVESYNC_OUTGOING_MAXPACKETS_SCRAPE;
+  while( packets_to_send > 0 && g_inquire_bucket < OT_BUCKET_COUNT ) {
+    ot_vector *torrents_list = mutex_bucket_lock( g_inquire_bucket );
+    unsigned int j;
+    for( j=0; j<torrents_list->size; ++j ) {
+      ot_torrent *torrent = (ot_torrent*)(torrents_list->data) + j;
+      memmove(g_scrapebuffer_pos, torrent->hash, sizeof(ot_hash));
+      g_scrapebuffer_pos += sizeof(ot_hash);
+      uint32_pack_big( (char*)g_scrapebuffer_pos    , (uint32_t)(g_now_minutes - torrent->peer_list->base ));
+      uint32_pack_big( (char*)g_scrapebuffer_pos + 4, (uint32_t)((uint64_t)(torrent->peer_list->down_count)>>32) );
+      uint32_pack_big( (char*)g_scrapebuffer_pos + 8, (uint32_t)torrent->peer_list->down_count );
+      g_scrapebuffer_pos += 12;
+
+      if( g_scrapebuffer_pos >= g_scrapebuffer_highwater ) {
+        socket_send4(g_socket_out, (char*)g_scrapebuffer_start, g_scrapebuffer_pos - g_scrapebuffer_start, groupip_1, LIVESYNC_PORT);
+        g_scrapebuffer_pos = g_scrapebuffer_start + sizeof( g_tracker_id ) + sizeof( uint32_t);
+        --packets_to_send;
+      }
+    }
+    mutex_bucket_unlock( g_inquire_bucket++, 0 );
+    if( !g_opentracker_running )
+      return;
+  }
+  if( g_inquire_bucket == OT_BUCKET_COUNT ) {
+    socket_send4(g_socket_out, (char*)g_scrapebuffer_start, g_scrapebuffer_pos - g_scrapebuffer_start, groupip_1, LIVESYNC_PORT);
+    g_inquire_inprogress = 0;
+  }
+}
+
+void livesync_handle_tell( ssize_t datalen ) {
+  int off = sizeof( g_tracker_id ) + sizeof( uint32_t );
+
+  /* Some instance is in progress of telling. Our inquiry was successful.
+     Don't ask again until we see next beacon. */
+  g_next_inquire_time = 0;
+  
+  /* Don't cause any new inquiries during another tracker's tell */
+  if( g_next_beacon_time - g_now_seconds < LIVESYNC_BEACON_INTERVAL )
+    g_next_beacon_time = g_now_seconds + LIVESYNC_BEACON_INTERVAL;
+
+  while( off + sizeof(ot_hash) + 12 <= (size_t)datalen ) {
+    ot_hash *hash = (ot_hash*)(g_inbuffer+off);
+    ot_vector *torrents_list = mutex_bucket_lock_by_hash(hash);
+    size_t     down_count_remote;
+    int exactmatch;
+    ot_torrent * torrent = vector_find_or_insert(torrents_list, hash, sizeof(ot_hash), OT_HASH_COMPARE_SIZE, &exactmatch);
+    if( !torrent ) {
+      mutex_bucket_unlock_by_hash( hash, 0 );
+      continue;
+    }
+
+    if( !exactmatch ) {
+      /* Create a new torrent entry, then */
+      int i; for(i=0;i<20;i+=4) WRITE32(&torrent->hash,i,READ32(hash,i));
+
+      if( !( torrent->peer_list = malloc( sizeof (ot_peerlist) ) ) ) {
+        vector_remove_torrent( torrents_list, torrent );
+        mutex_bucket_unlock_by_hash( hash, 0 );
+        continue;
+      }
+
+      byte_zero( torrent->peer_list, sizeof( ot_peerlist ) );
+      torrent->peer_list->base = g_now_minutes - uint32_read_big((char*)g_inbuffer+off+sizeof(ot_hash));
+    }
+
+    down_count_remote  = (size_t)(((uint64_t)uint32_read_big((char*)g_inbuffer+off+sizeof( ot_hash ) +     sizeof(uint32_t))) << 32);
+    down_count_remote |= (size_t)            uint32_read_big((char*)g_inbuffer+off+sizeof( ot_hash ) + 2 * sizeof(uint32_t));
+
+    if( down_count_remote > torrent->peer_list->down_count )
+      torrent->peer_list->down_count = down_count_remote;
+    /* else
+      We might think of sending a tell packet, if we have a much larger downloaded count
+     */
+
+    mutex_bucket_unlock( g_inquire_bucket++, exactmatch?0:1 );
+    if( !g_opentracker_running )
+      return;
+    off += sizeof(ot_hash) + 12;
+  }
+}
+#endif /* WANT_SYNC_SCRAPE */
+
 /* Tickle the live sync module from time to time, so no events get
- stuck when there's not enough traffic to fill udp packets fast
- enough */
+   stuck when there's not enough traffic to fill udp packets fast
+   enough */
 void livesync_ticker( ) {
-  if( ( g_now_seconds - livesync_lastpacket_time > LIVESYNC_MAXDELAY) &&
-      ( livesync_outbuffer_pos > livesync_outbuffer_start + sizeof( g_tracker_id ) ) )
-    livesync_issuepacket();
+  
+  /* livesync_issue_peersync sets g_next_packet_time */
+  if( g_now_seconds > g_next_packet_time &&
+     g_peerbuffer_pos > g_peerbuffer_start + sizeof( g_tracker_id ) )
+    livesync_issue_peersync();
+
+#ifdef WANT_SYNC_SCRAPE
+  /* Send first beacon after running at least LIVESYNC_FIRST_BEACON_DELAY
+     seconds and not more often than every LIVESYNC_BEACON_INTERVAL seconds */
+  if( g_now_seconds > g_next_beacon_time ) {
+    livesync_issue_beacon( );
+    g_next_beacon_time = g_now_seconds + LIVESYNC_BEACON_INTERVAL;
+  }
+
+  /* If we're interested in an inquiry and waited long enough to see all
+     tracker's beacons, go ahead and inquire */
+  if( g_next_inquire_time && g_now_seconds > g_next_inquire_time ) {
+    livesync_issue_inquire();
+
+    /* If packet gets lost, ask again after LIVESYNC_BEACON_INTERVAL */
+    g_next_inquire_time = g_now_seconds + LIVESYNC_BEACON_INTERVAL;
+  }
+
+  /* If we're in process of telling, let's tell. */
+  if( g_inquire_inprogress )
+    livesync_issue_tell( );
+
+#endif /* WANT_SYNC_SCRAPE */
+}
+
+/* Inform live sync about whats going on. */
+void livesync_tell( ot_hash * const info_hash, const ot_peer * const peer ) {
+  unsigned int i;
+  for(i=0;i<sizeof(ot_hash)/4;i+=4) WRITE32(g_peerbuffer_pos,i,READ32(info_hash,i));
+
+  WRITE32(g_peerbuffer_pos,sizeof(ot_hash)  ,READ32(peer,0));
+  WRITE32(g_peerbuffer_pos,sizeof(ot_hash)+4,READ32(peer,4));
+
+  g_peerbuffer_pos += sizeof(ot_hash)+8;
+
+  if( g_peerbuffer_pos >= g_peerbuffer_highwater )
+    livesync_issue_peersync();
 }
 
 static void * livesync_worker( void * args ) {
   uint8_t in_ip[4]; uint16_t in_port;
   ssize_t datalen;
-  int off;
 
-  args = args;
+  (void)args;
 
   while( 1 ) {
-    datalen = socket_recv4(g_livesync_socket_in, (char*)livesync_inbuffer, LIVESYNC_BUFFINSIZE, (char*)in_ip, &in_port);
-    off = 4;
+    datalen = socket_recv4(g_socket_in, (char*)g_inbuffer, LIVESYNC_INCOMING_BUFFSIZE, (char*)in_ip, &in_port);
 
-    if( datalen <= 0 )
+    /* Expect at least tracker id and packet type */
+    if( datalen <= (ssize_t)(sizeof( g_tracker_id ) + sizeof( uint32_t )) )
       continue;
-
-    if( datalen < (ssize_t)(sizeof( g_tracker_id ) + sizeof( ot_hash ) + sizeof( ot_peer ) ) ) {
-      /* TODO: log invalid sync packet */
+    if( !accesslist_isblessed((char*)in_ip, OT_PERMISSION_MAY_LIVESYNC))
       continue;
-    }
-
-    if( !accesslist_isblessed((char*)in_ip, OT_PERMISSION_MAY_LIVESYNC)) {
-      /* TODO: log invalid sync packet */
-      continue;
-    }
-
-    if( !memcmp( livesync_inbuffer, &g_tracker_id, sizeof( g_tracker_id ) ) ) {
+    if( !memcmp( g_inbuffer, &g_tracker_id, sizeof( g_tracker_id ) ) ) {
       /* TODO: log packet coming from ourselves */
       continue;
     }
 
-    /* Now basic sanity checks have been done on the live sync packet
-       We might add more testing and logging. */
-    while( off + (ssize_t)sizeof( ot_hash ) + (ssize_t)sizeof( ot_peer ) <= datalen ) {
-      ot_peer *peer = (ot_peer*)(livesync_inbuffer + off + sizeof(ot_hash));
-      ot_hash *hash = (ot_hash*)(livesync_inbuffer + off);
-
-      if( !g_opentracker_running )
-        return NULL;
-
-      if( OT_PEERFLAG(peer) & PEER_FLAG_STOPPED )
-        remove_peer_from_torrent(hash, peer, NULL, FLAG_MCA);
-      else
-        add_peer_to_torrent( hash, peer  WANT_SYNC_PARAM(1));
-
-      off += sizeof( ot_hash ) + sizeof( ot_peer );
+    switch( uint32_read_big( (char*)g_inbuffer ) ) {
+    case OT_SYNC_PEER:
+      livesync_handle_peersync( datalen );
+      break;
+#ifdef WANT_SYNC_SCRAPE
+    case OT_SYNC_SCRAPE_BEACON:
+      livesync_handle_beacon( datalen );
+      break;
+    case OT_SYNC_SCRAPE_INQUIRE:
+      livesync_handle_inquire( datalen );
+      break;
+    case OT_SYNC_SCRAPE_TELL:
+      livesync_handle_tell( datalen );
+      break;
+#endif /* WANT_SYNC_SCRAPE */
+    default:
+      break;
     }
 
-    stats_issue_event(EVENT_SYNC, 0, datalen / ((ssize_t)sizeof( ot_hash ) + (ssize_t)sizeof( ot_peer )));
+    /* Handle outstanding requests */
+    livesync_ticker( );
   }
+
   /* Never returns. */
   return NULL;
 }