Use timers for duplicate requests

Nothing was triggering request updates when timeouts expired. This is the simplest fix, no performance considered.

diff --git a/connection.go b/connection.go
index 54297b56f6e83f75ba857fbc7a3bb721d0ea4711..4195683e77267c82f96952ef19084c7d4d1b705c 100644 (file)
--- a/connection.go
+++ b/connection.go
@@ -512,7 +512,17 @@ func (cn *connection) request(r request, mw messageWriter) bool {
        }
        cn.validReceiveChunks[r] = struct{}{}
        cn.t.pendingRequests[r]++
-       cn.t.lastRequested[r] = time.Now()
+       cn.t.lastRequested[r] = time.AfterFunc(cn.t.duplicateRequestTimeout, func() {
+               torrent.Add("duplicate request timeouts", 1)
+               cn.mu().Lock()
+               defer cn.mu().Unlock()
+               delete(cn.t.lastRequested, r)
+               for cn := range cn.t.conns {
+                       if cn.PeerHasPiece(pieceIndex(r.Index)) {
+                               cn.updateRequests()
+                       }
+               }
+       })
        cn.updateExpectingChunks()
        return mw(pp.Message{
                Type:   pp.Request,
@@ -761,13 +771,10 @@ func (cn *connection) iterPendingRequests(piece int, f func(request) bool) bool
        return iterUndirtiedChunks(piece, cn.t, func(cs chunkSpec) bool {
                r := request{pp.Integer(piece), cs}
                if cn.t.requestStrategy == 3 {
-                       lr := cn.t.lastRequested[r]
-                       if !lr.IsZero() {
-                               if time.Since(lr) < cn.t.duplicateRequestTimeout {
-                                       return true
-                               } else {
-                                       torrent.Add("requests duplicated due to timeout", 1)
-                               }
+                       if _, ok := cn.t.lastRequested[r]; ok {
+                               // This piece has been requested on another connection, and
+                               // the duplicate request timer is still running.
+                               return true
                        }
                }
                return f(r)
@@ -1470,7 +1477,10 @@ func (c *connection) deleteRequest(r request) bool {
        }
        delete(c.requests, r)
        c.updateExpectingChunks()
-       delete(c.t.lastRequested, r)
+       if t, ok := c.t.lastRequested[r]; ok {
+               t.Stop()
+               delete(c.t.lastRequested, r)
+       }
        pr := c.t.pendingRequests
        pr[r]--
        n := pr[r]

diff --git a/torrent.go b/torrent.go
index d7bb2bdbac9bb1586182899f04056b9e7b9b433b..26da79c5917d579012f2bbe642073c394ca2a1ca 100644 (file)
--- a/torrent.go
+++ b/torrent.go
@@ -147,7 +147,7 @@ type Torrent struct {
        pendingRequests map[request]int
        // The last time we requested a chunk. Deleting the request from any
        // connection will clear this value.
-       lastRequested map[request]time.Time
+       lastRequested map[request]*time.Timer
 }
 
 func (t *Torrent) tickleReaders() {
@@ -407,7 +407,7 @@ func (t *Torrent) onSetInfo() {
        t.gotMetainfo.Set()
        t.updateWantPeersEvent()
        t.pendingRequests = make(map[request]int)
-       t.lastRequested = make(map[request]time.Time)
+       t.lastRequested = make(map[request]*time.Timer)
 }
 
 // Called when metadata for a torrent becomes available.
@@ -1240,6 +1240,9 @@ func (t *Torrent) assertNoPendingRequests() {
        if len(t.pendingRequests) != 0 {
                panic(t.pendingRequests)
        }
+       if len(t.lastRequested) != 0 {
+               panic(t.lastRequested)
+       }
 }
 
 func (t *Torrent) dropConnection(c *connection) {