Saves a list of peers when you pause a torrent, and tries to reconnect to them next time you resume it

libtransmission/fastresume.h

@@ -50,6 +50,8 @@
 #define FR_ID_DOWNLOADED        0x02
 /* number of bytes uploaded */
 #define FR_ID_UPLOADED          0x03
+/* IPs and ports of connectable peers */
+#define FR_ID_PEERS             0x04
 
 /* macros for the length of various pieces of the progress data */
 #define FR_MTIME_LEN( t ) \
@@ -126,6 +128,7 @@ static void fastResumeSave( tr_io_t * io )
     char    * path;
     uint8_t * buf;
     uint64_t  total;
+    int       size;
 
     buf = malloc( FR_PROGRESS_LEN( tor ) );
 
@@ -167,6 +170,13 @@ static void fastResumeSave( tr_io_t * io )
     total = tor->uploadedCur + tor->uploadedPrev;
     fastResumeWriteData( FR_ID_UPLOADED, &total, 8, 1, file );
 
+    /* Write IPs and ports of connectable peers, if any */
+    if( ( size = tr_peerGetConnectable( tor, &buf ) ) > 0 )
+    {
+        fastResumeWriteData( FR_ID_PEERS, buf, size, 1, file );
+        free( buf );
+    }
+
     fclose( file );
 
     tr_dbg( "Resume file '%s' written", path );
@@ -358,6 +368,20 @@ static int fastResumeLoad( tr_io_t * io )
                 }
                 break;
 
+            case FR_ID_PEERS:
+            {
+                uint8_t * buf = malloc( len );
+                if( 1 != fread( buf, len, 1, file ) )
+                {
+                    free( buf );
+                    fclose( file );
+                    return 1;
+                }
+                tr_peerAddCompactMany( tor, buf, len );
+                free( buf );
+                continue;
+            }
+
             default:
                 break;
         }

libtransmission/peer.c

@@ -150,6 +150,26 @@ void tr_peerAddCompact( tr_torrent_t * tor, struct in_addr addr,
     addWithAddr( tor, addr, port );
 }
 
+/***********************************************************************
+ * tr_peerAddCompactMany
+ ***********************************************************************
+ * Adds several peers in compact form
+ **********************************************************************/
+void tr_peerAddCompactMany( tr_torrent_t * tor, uint8_t * buf, int len )
+{
+    struct in_addr addr;
+    in_port_t port;
+    int i;
+
+    len /= 6;
+    for( i = 0; i < len; i++ )
+    {
+        memcpy( &addr, buf, 4 ); buf += 4;
+        memcpy( &port, buf, 2 ); buf += 2;
+        tr_peerAddCompact( tor, addr, port );
+    }
+}
+
 /***********************************************************************
  * tr_peerInit
  ***********************************************************************
@@ -616,3 +636,39 @@ void tr_peerBlame( tr_torrent_t * tor, tr_peer_t * peer,
     }
     tr_bitfieldRem( peer->blamefield, piece );
 }
+
+int tr_peerGetConnectable( tr_torrent_t * tor, uint8_t ** _buf )
+{
+    int count = 0;
+    uint8_t * buf = malloc( 6 * tor->peerCount );
+    tr_peer_t * peer;
+    int i;
+
+    for( i = 0; i < tor->peerCount; i++ )
+    {
+        peer = tor->peers[i];
+
+        /* Skip peers for which the connection isn't established,
+         * and peers that came from incoming connections */
+        if( peer->status < PEER_STATUS_CONNECTED )
+            continue;
+        if( peer->incoming )
+            continue;
+
+        memcpy( &buf[count*6], &peer->addr, 4 );
+        memcpy( &buf[count*6+4], &peer->port, 2 );
+        count++;
+    }
+
+    if( count < 1 )
+    {
+        free( buf );
+        *_buf = NULL;
+    }
+    else
+    {
+        *_buf = buf;
+    }
+
+    return count * 6;
+}

libtransmission/peer.h

@@ -29,6 +29,7 @@ typedef struct tr_peer_s tr_peer_t;
 
 void        tr_peerAddOld        ( tr_torrent_t *, char *, int );
 void        tr_peerAddCompact    ( tr_torrent_t *, struct in_addr, in_port_t );
+void        tr_peerAddCompactMany( tr_torrent_t *, uint8_t *, int );
 tr_peer_t * tr_peerInit          ( struct in_addr, in_port_t, int );
 void        tr_peerAttach        ( tr_torrent_t *, tr_peer_t * );
 void        tr_peerDestroy       ( tr_fd_t *, tr_peer_t * );
@@ -54,5 +55,6 @@ int         tr_peerIsOptimistic  ( tr_peer_t * );
 void        tr_peerBlame         ( tr_torrent_t *, tr_peer_t *,
                                    int piece, int success );
 struct in_addr * tr_peerAddress  ( tr_peer_t * );
+int         tr_peerGetConnectable( tr_torrent_t *, uint8_t ** );
 
 #endif