Network handling code skeleton stands, is untested and no configure code there, yet.

proxy.c

@@ -30,9 +30,11 @@
 #include "trackerlogic.h"
 #include "ot_vector.h"
 #include "ot_mutex.h"
-#include "ot_livesync.h"
 #include "ot_stats.h"
 
+#define WANT_SYNC_LIVE
+#include "ot_livesync.h"
+
 ot_ip6   g_serverip; 
 uint16_t g_serverport = 9009;
 uint32_t g_tracker_id;
@@ -49,6 +51,7 @@ int      g_self_pipe[2];
 
 #define LIVESYNC_OUTGOING_BUFFSIZE_PEERS     1480
 #define LIVESYNC_OUTGOING_WATERMARK_PEERS   (sizeof(ot_peer)+sizeof(ot_hash))
+#define LIVESYNC_MAXDELAY                    15      /* seconds */
 
 /* The amount of time a complete sync cycle should take */
 #define OT_SYNC_INTERVAL_MINUTES             2
@@ -65,10 +68,14 @@ static uint8_t  g_inbuffer[LIVESYNC_INCOMING_BUFFSIZE];
 
 /* For outgoing packets */
 static int64    g_socket_out = -1;
-//static uint8_t  g_outbuffer[STREAMSYNC_OUTGOING_BUFFSIZE];
+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;
 
 static void * livesync_worker( void * args );
 static void * streamsync_worker( void * args );
+static void   livesync_proxytell( uint8_t prefix, uint8_t *info_hash, uint8_t *peer );
 
 void exerr( char * message ) {
   fprintf( stderr, "%s\n", message );
@@ -226,15 +233,31 @@ enum {
 #define PROXYPEER_SETCONNECTED(flag)      (flag)=(((flag)&FLAG_OUTGOING)|FLAG_CONNECTED)
 
 typedef struct {
-  int      state;          /* Whether we want to connect, how far our handshake is, etc. */
+  int      state;           /* Whether we want to connect, how far our handshake is, etc. */
-  ot_ip6   ip;             /* The peer to connect to */
+  ot_ip6   ip;              /* The peer to connect to */
-  uint16_t port;           /* The peers port */
+  uint16_t port;            /* The peers port */
-  uint8_t *indata;         /* Any data not processed yet */
+  uint8_t  indata[8192*16]; /* Any data not processed yet */
-  size_t   indata_length;  /* Length of unprocessed data */
+  size_t   indata_length;   /* Length of unprocessed data */
-  uint32_t tracker_id;     /* How the other end greeted */
+  uint32_t tracker_id;      /* How the other end greeted */
-  int64    fd;             /* A file handle, if connected, <= 0 is disconnected (0 initially, -1 else) */
+  int64    fd;              /* A file handle, if connected, <= 0 is disconnected (0 initially, -1 else) */
-  io_batch outdata;        /* The iobatch containing our sync data */
+  io_batch outdata;         /* The iobatch containing our sync data */
+
+  int      packet_tcount;   /* Number of unprocessed torrents in packet we currently receive */
+  char     packet_tprefix;  /* Prefix byte for all torrents in current packet */
+  char     packet_type;     /* Type of current packet */
+  uint32_t packet_tid;      /* Tracker id for current packet */
+
 } proxy_peer;
+static void process_indata( proxy_peer * peer );
+
+void reset_info_block( proxy_peer * peer ) {
+  peer->indata_length = 0;
+  peer->tracker_id    = 0;
+  peer->fd            = -1;
+  peer->packet_tcount = 0;
+  iob_reset( &peer->outdata );
+  PROXYPEER_SETDISCONNECTED( peer->state );
+}
 
 /* Number of connections to peers
    * If a peer's IP is set, we try to reconnect, when the connection drops
@@ -266,12 +289,8 @@ static void handle_reconnects( void ) {
       io_setcookie(newfd,g_connections+i);
 
       /* Prepare connection info block */
-      free( g_connections[i].indata );
+      reset_info_block( g_connections+i );
-      g_connections[i].indata        = 0;
-      g_connections[i].indata_length = 0;
       g_connections[i].fd            = newfd;
-      g_connections[i].tracker_id    = 0;
-      iob_reset( &g_connections[i].outdata );
       PROXYPEER_SETCONNECTING( g_connections[i].state );
     }
   g_connection_reconn = time(NULL) + 30;
@@ -305,16 +324,10 @@ static void handle_accept( int64 serversocket ) {
       }
 
       /* Prepare connection info block */
-      free( g_connections[i].indata );
+      reset_info_block( g_connections+i );
-      g_connections[i].indata        = 0;
-      g_connections[i].indata_length = 0;
-      g_connections[i].port          = port;
-      g_connections[i].fd            = newfd;
-      g_connections[i].tracker_id    = 0;
-      iob_reset( &g_connections[i].outdata );
-      g_connections[i].tracker_id    = 0;
-
       PROXYPEER_SETCONNECTING( g_connections[i].state );
+      g_connections[i].port = port;
+      g_connections[i].fd   = newfd;
 
       io_setcookie( newfd, g_connections + i );
 
@@ -328,19 +341,25 @@ static void handle_accept( int64 serversocket ) {
 
 /* New sync data on the stream */
 static void handle_read( int64 peersocket ) {
+  int i;
+  int64 datalen;
   uint32_t tracker_id;
   proxy_peer *peer = io_getcookie( peersocket );
+
   if( !peer ) {
     /* Can't happen ;) */
-    close( peersocket );
+    io_close( peersocket );
     return;
   }
   switch( peer->state & FLAG_MASK ) {
-  case FLAG_DISCONNECTED: break; /* Shouldnt happen */
+  case FLAG_DISCONNECTED:
+    io_close( peersocket );
+    break; /* Shouldnt happen */
   case FLAG_CONNECTING:
   case FLAG_WAITTRACKERID:
-    /* We want at least the first four bytes to come at once, to avoid keeping extra states (for now) */
+    /* We want at least the first four bytes to come at once, to avoid keeping extra states (for now)
-    if( io_tryread( peersocket, &tracker_id, sizeof( tracker_id ) ) != sizeof( tracker_id ) )
+       This also catches 0 bytes reads == EOF and negative values, denoting connection errors */
+    if( io_tryread( peersocket, (void*)&tracker_id, sizeof( tracker_id ) ) != sizeof( tracker_id ) )
       goto close_socket;
 
     /* See, if we already have a connection to that peer */
@@ -363,12 +382,20 @@ static void handle_read( int64 peersocket ) {
     break;
 close_socket:
     io_close( peersocket );
-    PROXYPEER_SETDISCONNECTED( peer->state );
+    reset_info_block( peer ); 
     break;
   case FLAG_CONNECTED:
-    
+    /* Here we acutally expect data from peer
+       indata_length should be less than 20+256*7 bytes, for incomplete torrent entries */
+    datalen = io_tryread( peersocket, (void*)(peer->indata + peer->indata_length), sizeof( peer->indata ) - peer->indata_length ); 
+    if( !datalen || datalen < -1 ) {
+      io_close( peersocket );
+      reset_info_block( peer );
+    } else if( datalen > 0 ) {
+      peer->indata_length += datalen;
+      process_indata( peer );
+    }
     break;
-
   }
 }
 
@@ -377,13 +404,22 @@ static void handle_write( int64 peersocket ) {
   proxy_peer *peer = io_getcookie( peersocket );
   if( !peer ) { 
     /* Can't happen ;) */
-    close( peersocket );
+    io_close( peersocket );
     return;
   }
 
   switch( peer->state & FLAG_MASK ) {
-  case FLAG_DISCONNECTED: break; /* Shouldnt happen */
+  case FLAG_DISCONNECTED:
+  default: /* Should not happen */
+    io_close( peersocket );
+    break;
   case FLAG_CONNECTING:
+    /* Ensure that the connection is established and handle connection error */
+    if( peer->state & FLAG_OUTGOING && !socket_connected( peersocket ) ) {
+        io_close( peersocket );
+        break;
+    }
+
     io_trywrite( peersocket, (void*)&g_tracker_id, sizeof( g_tracker_id ) );
     PROXYPEER_SETWAITTRACKERID( peer->state );
     io_dontwantwrite( peersocket );
@@ -396,15 +432,12 @@ static void handle_write( int64 peersocket ) {
       break;
     case -3: /* an error occured */
       io_close( peersocket );
-      PROXYPEER_SETDISCONNECTED( peer->state );
+      reset_info_block( peer );
-      iob_reset( &peer->outdata );
+      break;
-      free( peer->indata );
     default: /* Normal operation or eagain */
       break;
     }
     break;
-  default:
-    break;
   }
 
   return;
@@ -414,6 +447,14 @@ static void server_mainloop() {
   int64 sock;
   tai6464 now;
 
+  /* inlined livesync_init() */
+  memset( g_peerbuffer_start, 0, sizeof( g_peerbuffer_start ) ); 
+  g_peerbuffer_pos = g_peerbuffer_start;
+  memcpy( 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);
+  g_next_packet_time = time(NULL) + LIVESYNC_MAXDELAY;
+
   while(1) {
     /* See, if we need to connect to anyone */
     if( time(NULL) > g_connection_reconn )
@@ -436,6 +477,8 @@ static void server_mainloop() {
     /* Loop over writable sockets */
     while( ( sock = io_canwrite( ) ) != -1 )
       handle_write( sock );
+
+    livesync_ticker( );
   }
 }
 
@@ -600,6 +643,68 @@ unlock_continue:
   return 0;
 }
 
+static void livesync_issue_peersync( ) {
+  socket_send4(g_socket_out, (char*)g_peerbuffer_start, g_peerbuffer_pos - g_peerbuffer_start,
+               groupip_1, LIVESYNC_PORT);
+  g_peerbuffer_pos   = g_peerbuffer_start + sizeof( g_tracker_id ) + sizeof( uint32_t );
+  g_next_packet_time = time(NULL) + LIVESYNC_MAXDELAY;
+}
+
+void livesync_ticker( ) {
+  /* livesync_issue_peersync sets g_next_packet_time */
+  if( time(NULL) > g_next_packet_time &&
+     g_peerbuffer_pos > g_peerbuffer_start + sizeof( g_tracker_id ) )
+    livesync_issue_peersync();
+}
+
+static void livesync_proxytell( uint8_t prefix, uint8_t *info_hash, uint8_t *peer ) {
+  *g_peerbuffer_pos = prefix;
+  memcpy( g_peerbuffer_pos + 1, info_hash, sizeof(ot_hash) - 1 );
+  memcpy( g_peerbuffer_pos + sizeof(ot_hash), peer, sizeof(ot_peer) - 1 );
+
+  g_peerbuffer_pos += sizeof(ot_hash) + sizeof(ot_peer);
+
+  if( g_peerbuffer_pos >= g_peerbuffer_highwater )
+    livesync_issue_peersync();
+}
+
+static void process_indata( proxy_peer * peer ) {
+  int ensuremem, consumed, peers;
+  uint8_t *data    = peer->indata, *hash;
+  uint8_t *dataend = data + peer->indata_length;
+
+  while( 1 ) {
+    /* If we're not inside of a packet, make a new one */
+    if( !peer->packet_tcount ) {
+      /* Ensure the header is complete or postpone processing */
+      if( data + 8 > dataend ) break;
+      memcpy( &peer->packet_tid, data, sizeof(peer->packet_tid) );
+      peer->packet_type    = data[4];
+      peer->packet_tprefix = data[5];
+      peer->packet_tcount  = data[6] * 256 + data[7];
+      data += 8;
+    }
+
+    /* ensure size for the complete torrent block */
+    if( data + 26 > dataend ) break;
+    peers = peer->packet_type ? peer->packet_type : data[19];
+    ensuremem = 19 + ( peer->packet_type == 0 ) + 7 * peers;
+    if( data + ensuremem > dataend ) break;
+
+    hash = data;
+    data += 19 + ( peer->packet_type == 0 );
+
+    while( peers-- ) {
+      livesync_proxytell( peer->packet_tprefix, hash, data );
+      data += 7;
+    }
+  }
+
+  consumed = data - peer->indata;
+  memmove( peer->indata, data, peer->indata_length - consumed );
+  peer->indata_length -= consumed;
+}
+
 static void * livesync_worker( void * args ) {
   (void)args;
   while( 1 ) {