support for udp scrape

opentracker.c

@@ -315,7 +315,7 @@ SCRAPE_WORKAROUND:
     }
 
     /* Enough for http header + whole scrape string */
-    if( !( reply_size = return_scrape_for_torrent( hash, SUCCESS_HTTP_HEADER_LENGTH + static_outbuf ) ) ) HTTPERROR_500;
+    if( !( reply_size = return_tcp_scrape_for_torrent( hash, SUCCESS_HTTP_HEADER_LENGTH + static_outbuf ) ) ) HTTPERROR_500;
 
     ot_overall_tcp_successfulannounces++;
     break;
@@ -590,7 +590,7 @@ static void handle_udp4( int64 serversocket ) {
   unsigned long *outpacket = (unsigned long*)static_outbuf;
   unsigned long  numwant, left, event;
   uint16         port, remoteport;
-  size_t         r;
+  size_t         r, r_out;
 
   r = socket_recv4( serversocket, static_inbuf, 8192, remoteip, &remoteport);
 
@@ -647,7 +647,7 @@ static void handle_udp4( int64 serversocket ) {
         if( !torrent )
           return; /* XXX maybe send error */
 
-        outpacket[0] = htonl( 1 );
+        outpacket[0] = htonl( 1 );    /* announce action */
         outpacket[1] = inpacket[12/4];
         r = 8 + return_peers_for_torrent( torrent, numwant, static_outbuf + 8, 0 );
         socket_send4( serversocket, static_outbuf, r, remoteip, remoteport );
@@ -656,7 +656,14 @@ static void handle_udp4( int64 serversocket ) {
       break;
 
     case 2: /* This is a scrape action */
-      ot_overall_udp_connections--; // subtract again because we don't answer scrapes but it is also not an error
+      outpacket[0] = htonl( 2 );    /* scrape action */
+      outpacket[1] = inpacket[12/4];
+
+      for( r_out = 0; ( r_out * 20 < r - 16) && ( r_out <= 74 ); r_out++ )
+        return_udp_scrape_for_torrent( (ot_hash*)( static_inbuf + 16 + 20 * r_out ), static_outbuf + 8 + 12 * r_out );
+
+      socket_send4( serversocket, static_outbuf, 8 + 12 * r_out, remoteip, remoteport );
+      ot_overall_udp_successfulannounces++;
       break;
   }
 }

trackerlogic.c

@@ -408,7 +408,33 @@ size_t return_memstat_for_tracker( char **reply ) {
 }
 
 /* Fetches scrape info for a specific torrent */
-size_t return_scrape_for_torrent( ot_hash *hash, char *reply ) {
+size_t return_udp_scrape_for_torrent( ot_hash *hash, char *reply ) {
+  int          exactmatch, i;
+  size_t       peers = 0, seeds = 0;
+  ot_vector   *torrents_list = &all_torrents[*hash[0]];
+  ot_torrent  *torrent = binary_search( hash, torrents_list->data, torrents_list->size, sizeof( ot_torrent ), OT_HASH_COMPARE_SIZE, &exactmatch );
+
+  if( !exactmatch ) {
+    memset( reply, 0, 12);
+  }
+  else
+  {
+    unsigned long *r = (unsigned long*) reply;
+    clean_peerlist( NOW, torrent->peer_list );
+
+    for( i=0; i<OT_POOLS_COUNT; ++i ) {
+      peers += torrent->peer_list->peers[i].size;
+      seeds += torrent->peer_list->seed_count[i];
+    }
+    r[0] = seeds;
+    r[1] = torrent->peer_list->downloaded;
+    r[2] = peers-seeds;
+  }
+  return 12;
+}
+
+/* Fetches scrape info for a specific torrent */
+size_t return_tcp_scrape_for_torrent( ot_hash *hash, char *reply ) {
   char        *r = reply;
   int          exactmatch, i;
   size_t       peers = 0, seeds = 0;

trackerlogic.h

@@ -96,7 +96,8 @@ enum { STATS_MRTG, STATS_TOP5, STATS_DMEM, STATS_TCP, STATS_UDP };
 ot_torrent *add_peer_to_torrent( ot_hash *hash, ot_peer *peer );
 size_t return_peers_for_torrent( ot_torrent *torrent, size_t amount, char *reply, int is_tcp );
 size_t return_fullscrape_for_tracker( char **reply );
-size_t return_scrape_for_torrent( ot_hash *hash, char *reply );
+size_t return_tcp_scrape_for_torrent( ot_hash *hash, char *reply );
+size_t return_udp_scrape_for_torrent( ot_hash *hash, char *reply );
 size_t return_sync_for_torrent( ot_hash *hash, char **reply );
 size_t return_stats_for_tracker( char *reply, int mode );
 size_t return_memstat_for_tracker( char **reply );