Merge pull request #248 from perkeep/packetwrite
Write packet length header & payload together on the wire.
diff --git a/packet.go b/packet.go
index 4eec06d..e2dec7a 100644
--- a/packet.go
+++ b/packet.go
@@ -125,15 +125,14 @@
} else if debugDumpTxPacket {
debug("send packet: %s %d bytes", fxp(bb[0]), len(bb))
}
- l := uint32(len(bb))
- hdr := []byte{byte(l >> 24), byte(l >> 16), byte(l >> 8), byte(l)}
- _, err = w.Write(hdr)
+ // Slide packet down 4 bytes to make room for length header.
+ packet := append(bb, make([]byte, 4)...) // optimistically assume bb has capacity
+ copy(packet[4:], bb)
+ binary.BigEndian.PutUint32(packet[:4], uint32(len(bb)))
+
+ _, err = w.Write(packet)
if err != nil {
- return errors.Errorf("failed to send packet header: %v", err)
- }
- _, err = w.Write(bb)
- if err != nil {
- return errors.Errorf("failed to send packet body: %v", err)
+ return errors.Errorf("failed to send packet: %v", err)
}
return nil
}
