Live sync is now handled in its own thread. Therefore it now creates and handles its own sockets.

ot_livesync.c

@@ -7,9 +7,11 @@
 #include <sys/types.h>
 #include <sys/uio.h>
 #include <string.h>
+#include <pthread.h>
 
 /* Libowfat */
 #include "socket.h"
+#include "ndelay.h"
 
 /* Opentracker */
 #include "trackerlogic.h"
@@ -17,10 +19,23 @@
 #include "ot_accesslist.h"
 
 #ifdef WANT_SYNC_LIVE
-char groupip_1[4] = { LIVESYNC_MCASTDOMAIN_1 };
+
+char groupip_1[4] = { 224,0,23,42 };
+
+#define LIVESYNC_BUFFINSIZE (256*256)
+#define LIVESYNC_BUFFSIZE  1504
+#define LIVESYNC_BUFFWATER (sizeof(ot_peer)+sizeof(ot_hash))
+
+#define LIVESYNC_MAXDELAY  15
+
+/* Forward declaration */
+static void * livesync_worker( void * args );
 
 /* For outgoing packets */
-int64 g_livesync_socket = -1;
+static int64 g_livesync_socket_in = -1;
+
+/* For incoming packets */
+static int64 g_livesync_socket_out = -1;
 
 static uint8_t  livesync_inbuffer[LIVESYNC_BUFFINSIZE];
 static uint8_t  livesync_outbuffer_start[ LIVESYNC_BUFFSIZE ];
@@ -28,34 +43,49 @@ 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 pthread_t thread_id;
 void livesync_init( ) {
-  if( g_livesync_socket == -1 )
+  if( g_livesync_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;
+
+  pthread_create( &thread_id, NULL, livesync_worker, NULL );
 }
 	
 void livesync_deinit() {
-	
+  pthread_cancel( thread_id );
 }
 
 void livesync_bind_mcast( char *ip, uint16_t port) {
   char tmpip[4] = {0,0,0,0};
-  if( g_livesync_socket != -1 )
+
-    exerr("Livesync listen ip specified twice.");
+  if( g_livesync_socket_in != -1 )
-  if( socket_mcjoin4( ot_try_bind(tmpip, port, FLAG_MCA ), groupip_1, ip ) )
+    exerr("Error: Livesync listen ip specified twice.");
-    exerr("Cant join mcast group.");
+
-  g_livesync_socket = ot_try_bind( ip, port, FLAG_UDP );
+  if( ( g_livesync_socket_in = socket_udp4( )) < 0)
-  io_dontwantread(g_livesync_socket);
+    exerr("Error: Cant create live sync incoming socket." );
-
+  ndelay_off(g_livesync_socket_in);
-  socket_mcttl4(g_livesync_socket, 1);
+
-  socket_mcloop4(g_livesync_socket, 0);
+  if( socket_bind4_reuse( g_livesync_socket_in, tmpip, port ) == -1 )
+    exerr("Error: Cant bind live sync incoming socket." );
+
+  if( socket_mcjoin4( g_livesync_socket_in, groupip_1, ip ) )
+    exerr("Error: Cant make live sync incoming socket join mcast group.");
+
+  if( ( g_livesync_socket_out = socket_udp4()) < 0)
+    exerr("Error: Cant create live sync outgoing socket." );
+  if( socket_bind4_reuse( g_livesync_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);
 }
 
 static void livesync_issuepacket( ) {
-	socket_send4(g_livesync_socket, (char*)livesync_outbuffer_start, livesync_outbuffer_pos - livesync_outbuffer_start,
+  socket_send4(g_livesync_socket_out, (char*)livesync_outbuffer_start, livesync_outbuffer_pos - livesync_outbuffer_start,
                groupip_1, LIVESYNC_PORT);
   livesync_outbuffer_pos = livesync_outbuffer_start + sizeof( g_tracker_id );
   livesync_lastpacket_time = g_now;
@@ -81,41 +111,51 @@ void livesync_ticker( ) {
     livesync_issuepacket();
 }
 
-/* Handle an incoming live sync packet */
+static void * livesync_worker( void * args ) {
-void handle_livesync( int64 serversocket ) {
   uint8_t in_ip[4]; uint16_t in_port;
-  ssize_t datalen = socket_recv4(serversocket, (char*)livesync_inbuffer, LIVESYNC_BUFFINSIZE, (char*)in_ip, &in_port);
+  ssize_t datalen;
-  int off = 4;
+  int off;
-
-  if( datalen < (ssize_t)(sizeof( g_tracker_id ) + sizeof( ot_hash ) + sizeof( ot_peer ) ) ) {
-    // TODO: log invalid sync packet
-    return;
-  }
-
-  if( !accesslist_isblessed((char*)in_ip, OT_PERMISSION_MAY_LIVESYNC)) {
-    // TODO: log invalid sync packet
-    return;
-  }
-
-  if( !memcmp( livesync_inbuffer, &g_tracker_id, sizeof( g_tracker_id ) ) ) {
-    // TODO: log packet coming from ourselves
-    return;
-  }
-
-  // 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( OT_FLAG(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 );
-  }
   
+  args = args;
+
+  while( 1 ) {
+    datalen = socket_recv4(g_livesync_socket_in, (char*)livesync_inbuffer, LIVESYNC_BUFFINSIZE, (char*)in_ip, &in_port);
+    off = 4;
+
+    if( datalen <= 0 )
+      continue;
+
+    if( datalen < (ssize_t)(sizeof( g_tracker_id ) + sizeof( ot_hash ) + sizeof( ot_peer ) ) ) {
+      // TODO: log invalid sync packet
+      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 ) ) ) {
+      // 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( OT_FLAG(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 );
+    }
+  }
+  /* Never returns. */
+  return NULL;
 }
 
 #endif

ot_livesync.h

@@ -10,14 +10,14 @@
 #include "trackerlogic.h"
 
 /*
-  Syncing is done as udp packets in the multicast domain 224.23.42.N port 9696
+  Syncing is done as udp packets in the multicast domain 224.0.42.N port 9696
 
   Each tracker should join the multicast group and send its live sync packets
   to that group, using a ttl of 1
 
   Format of a live sync packet is straight forward and depends on N:
 
-  For N == 1: (simple tracker2tracker sync)
+  For N == 23: (simple tracker2tracker sync)
     0x0000 0x04 id of tracker instance
   [ 0x0004 0x14 info_hash
     0x0018 0x04 peer's ipv4 address
@@ -25,7 +25,7 @@
     0x0020 0x02 peer flags v1 ( SEEDING = 0x80, COMPLETE = 0x40, STOPPED = 0x20 )
   ]*
  
-  For N == 2: (aggregator syncs)
+  For N == 24: (aggregator syncs)
     0x0000 0x04 id of tracker instance
   [ 0x0004 0x14 info_hash
     0x0018 0x01 number of peers
@@ -41,18 +41,6 @@
 #ifdef WANT_SYNC_LIVE
 
 #define LIVESYNC_PORT 9696
-#define LIVESYNC_MCASTDOMAIN_1 224,23,42,1
-#define LIVESYNC_MCASTDOMAIN_2 224,23,42,2
-extern char groupip_1[4];
-extern char groupip_2[4];
-
-extern int64 g_livesync_socket;
-
-#define LIVESYNC_BUFFINSIZE (256*256)
-#define LIVESYNC_BUFFSIZE  1504
-#define LIVESYNC_BUFFWATER (sizeof(ot_peer)+sizeof(ot_hash))
-
-#define LIVESYNC_MAXDELAY  15
 
 void livesync_init();
 void livesync_deinit();