Misc debug status, pex conn tracking improvements

[btrtrc.git] / peer_protocol / handshake.go

diff --git a/peer_protocol/handshake.go b/peer_protocol/handshake.go
index acdc3da58faa2af1cb3e1bce906488751edaf148..76dc2b05d250f422b7dfd6d9bbbfcc5b985181a6 100644 (file)
--- a/peer_protocol/handshake.go
+++ b/peer_protocol/handshake.go
@@ -5,7 +5,10 @@ import (
        "errors"
        "fmt"
        "io"
+       "math/bits"
        "strconv"
+       "strings"
+       "unsafe"
 
        "github.com/anacrolix/torrent/metainfo"
 )
@@ -33,8 +36,31 @@ type (
        PeerExtensionBits [8]byte
 )
 
+var bitTags = []struct {
+       bit ExtensionBit
+       tag string
+}{
+       // Ordered by their base protocol type values (PORT, fast.., EXTENDED)
+       {ExtensionBitDHT, "dht"},
+       {ExtensionBitFast, "fast"},
+       {ExtensionBitExtended, "ext"},
+}
+
 func (pex PeerExtensionBits) String() string {
-       return hex.EncodeToString(pex[:])
+       pexHex := hex.EncodeToString(pex[:])
+       tags := make([]string, 0, len(bitTags)+1)
+       for _, bitTag := range bitTags {
+               if pex.GetBit(bitTag.bit) {
+                       tags = append(tags, bitTag.tag)
+                       pex.SetBit(bitTag.bit, false)
+               }
+       }
+       unknownCount := bits.OnesCount64(*(*uint64)((unsafe.Pointer(unsafe.SliceData(pex[:])))))
+       if unknownCount != 0 {
+               tags = append(tags, fmt.Sprintf("%v unknown", unknownCount))
+       }
+       return fmt.Sprintf("%v (%s)", pexHex, strings.Join(tags, ", "))
+
 }
 
 func NewPeerExtensionBytes(bits ...ExtensionBit) (ret PeerExtensionBits) {