Rename prioritized_peers go files

[btrtrc.git] / prioritized-peers.go

diff --git a/prioritized-peers.go b/prioritized-peers.go
new file mode 100644 (file)
index 0000000..443d720
--- /dev/null
+++ b/prioritized-peers.go
@@ -0,0 +1,82 @@
+package torrent
+
+import (
+       "hash/maphash"
+
+       "github.com/anacrolix/multiless"
+       "github.com/google/btree"
+)
+
+// Peers are stored with their priority at insertion. Their priority may
+// change if our apparent IP changes, we don't currently handle that.
+type prioritizedPeersItem struct {
+       prio peerPriority
+       p    PeerInfo
+}
+
+var hashSeed = maphash.MakeSeed()
+
+func (me prioritizedPeersItem) addrHash() int64 {
+       var h maphash.Hash
+       h.SetSeed(hashSeed)
+       h.WriteString(me.p.Addr.String())
+       return int64(h.Sum64())
+}
+
+func (me prioritizedPeersItem) Less(than btree.Item) bool {
+       other := than.(prioritizedPeersItem)
+       return multiless.New().Bool(
+               me.p.Trusted, other.p.Trusted).Uint32(
+               me.prio, other.prio).Int64(
+               me.addrHash(), other.addrHash(),
+       ).Less()
+}
+
+type prioritizedPeers struct {
+       om      *btree.BTree
+       getPrio func(PeerInfo) peerPriority
+}
+
+func (me *prioritizedPeers) Each(f func(PeerInfo)) {
+       me.om.Ascend(func(i btree.Item) bool {
+               f(i.(prioritizedPeersItem).p)
+               return true
+       })
+}
+
+func (me *prioritizedPeers) Len() int {
+       if me == nil || me.om == nil {
+               return 0
+       }
+       return me.om.Len()
+}
+
+// Returns true if a peer is replaced.
+func (me *prioritizedPeers) Add(p PeerInfo) bool {
+       return me.om.ReplaceOrInsert(prioritizedPeersItem{me.getPrio(p), p}) != nil
+}
+
+// Returns true if a peer is replaced.
+func (me *prioritizedPeers) AddReturningReplacedPeer(p PeerInfo) (ret PeerInfo, ok bool) {
+       item := me.om.ReplaceOrInsert(prioritizedPeersItem{me.getPrio(p), p})
+       if item == nil {
+               return
+       }
+       ret = item.(prioritizedPeersItem).p
+       ok = true
+       return
+}
+
+func (me *prioritizedPeers) DeleteMin() (ret prioritizedPeersItem, ok bool) {
+       i := me.om.DeleteMin()
+       if i == nil {
+               return
+       }
+       ret = i.(prioritizedPeersItem)
+       ok = true
+       return
+}
+
+func (me *prioritizedPeers) PopMax() PeerInfo {
+       return me.om.DeleteMax().(prioritizedPeersItem).p
+}