Reduce the number of HAVE messages sent by only sending them to peers missing

the piece. Remove seeder peers when our download is finished and remove peers
who doesn't show any interest for a long time when we're seeding.

btpd/download.c

@@ -79,14 +79,17 @@ dl_on_choke(struct peer *p)
 void
 dl_on_ok_piece(struct net *n, uint32_t piece)
 {
-    struct peer *p;
+    struct peer *p, *next;
     struct piece *pc = dl_find_piece(n, piece);
 
     btpd_log(BTPD_L_POL, "Got piece: %u.\n", pc->index);
 
     struct net_buf *have = nb_create_have(pc->index);
+    nb_hold(have);
     BTPDQ_FOREACH(p, &n->peers, p_entry)
-        peer_send(p, have);
+        if (!peer_has(p, pc->index))
+            peer_send(p, have);
+    nb_drop(have);
 
     if (n->endgame)
         BTPDQ_FOREACH(p, &n->peers, p_entry)
@@ -100,8 +103,11 @@ dl_on_ok_piece(struct net *n, uint32_t piece)
         btpd_log(BTPD_L_BTPD, "Finished downloading '%s'.\n",
             torrent_name(n->tp));
         tr_complete(n->tp);
-        BTPDQ_FOREACH(p, &n->peers, p_entry)
+        BTPDQ_FOREACH_MUTABLE(p, &n->peers, p_entry, next) {
             assert(p->nwant == 0);
+            if (peer_full(p))
+                peer_kill(p);
+        }
     }
 }
 

btpd/net_types.h

@@ -63,6 +63,7 @@ struct peer {
 
     long t_created;
     long t_wantwrite;
+    long t_nointerest;
 
     struct {
         uint32_t msg_len;

btpd/peer.c

@@ -250,6 +250,7 @@ peer_unwant(struct peer *p, uint32_t index)
     p->nwant--;
     if (p->nwant == 0) {
         p->flags &= ~PF_I_WANT;
+        p->t_nointerest = btpd_seconds;
         if (p->nreqs_out == 0)
             peer_send(p, nb_create_uninterest());
         else
@@ -265,6 +266,7 @@ peer_create_common(int sd)
     p->sd = sd;
     p->flags = PF_I_CHOKE | PF_P_CHOKE;
     p->t_created = btpd_seconds;
+    p->t_nointerest = btpd_seconds;
     BTPDQ_INIT(&p->my_reqs);
     BTPDQ_INIT(&p->outq);
 
@@ -416,6 +418,7 @@ peer_on_uninterest(struct peer *p)
         return;
     else {
         p->flags &= ~PF_P_WANT;
+        p->t_nointerest = btpd_seconds;
         ul_on_uninterest(p);
     }
 }
@@ -512,13 +515,23 @@ peer_on_cancel(struct peer *p, uint32_t index, uint32_t begin,
 void
 peer_on_tick(struct peer *p)
 {
-    if ((p->flags & PF_ATTACHED) == 0 && btpd_seconds - p->t_created >= 60) {
-        btpd_log(BTPD_L_CONN, "hand shake timed out.\n");
-        peer_kill(p);
-    } else if (!BTPDQ_EMPTY(&p->outq) && btpd_seconds - p->t_wantwrite >= 60) {
-        btpd_log(BTPD_L_CONN, "write attempt timed out.\n");
-        peer_kill(p);
+    if (p->flags & PF_ATTACHED) {
+        if (!BTPDQ_EMPTY(&p->outq) && btpd_seconds - p->t_wantwrite >= 60) {
+            btpd_log(BTPD_L_CONN, "write attempt timed out.\n");
+            goto kill;
+        }
+        if ((cm_full(p->n->tp) && !(p->flags & PF_P_WANT) &&
+                btpd_seconds - p->t_nointerest >= 600)) {
+            btpd_log(BTPD_L_CONN, "no interest for 10 minutes.\n");
+            goto kill;
+        }
+    } else if (btpd_seconds - p->t_created >= 60) {
+            btpd_log(BTPD_L_CONN, "hand shake timed out.\n");
+            goto kill;
     }
+    return;
+kill:
+    peer_kill(p);
 }
 
 int