From 9ca1a491782257c97fc41f17119a2cdaac8bd7cf Mon Sep 17 00:00:00 2001
From: scruzin <anoble@gmail.com>
Date: Sun, 13 Jan 2019 07:46:47 +1030
Subject: [PATCH] Removed unused chunk type and associated unused code.

---
 rtmp/packet.go | 28 ++++++++--------------------
 1 file changed, 8 insertions(+), 20 deletions(-)

diff --git a/rtmp/packet.go b/rtmp/packet.go
index adbe32f3..70ead13a 100644
--- a/rtmp/packet.go
+++ b/rtmp/packet.go
@@ -91,19 +91,11 @@ type packet struct {
 	info            int32
 	bodySize        uint32
 	bytesRead       uint32
-	chunk           *chunk
 	header          []byte
 	body            []byte
 }
 
-// chunk defines an RTMP packet chunk.
-type chunk struct {
-	headerSize int32
-	data       []byte
-	header     [fullHeaderSize]byte
-}
-
-// read reads a packet.
+// read reads an RTMP packet.
 func (pkt *packet) read(s *Session) error {
 	var hbuf [fullHeaderSize]byte
 	header := hbuf[:]
@@ -222,13 +214,6 @@ func (pkt *packet) read(s *Session) error {
 		chunkSize = toRead
 	}
 
-	if pkt.chunk != nil {
-		panic("non-nil chunk")
-		pkt.chunk.headerSize = int32(hSize)
-		copy(pkt.chunk.header[:], hbuf[:hSize])
-		pkt.chunk.data = pkt.body[pkt.bytesRead : pkt.bytesRead+uint32(chunkSize)]
-	}
-
 	_, err = s.read(pkt.body[pkt.bytesRead:][:chunkSize])
 	if err != nil {
 		s.log(DebugLevel, pkg+"failed to read packet body", "error", err.Error())
@@ -237,7 +222,7 @@ func (pkt *packet) read(s *Session) error {
 
 	pkt.bytesRead += uint32(chunkSize)
 
-	// keep the packet as ref for other packets on this channel
+	// keep the packet as a reference for other packets on this channel
 	if s.channelsIn[pkt.channel] == nil {
 		s.channelsIn[pkt.channel] = &packet{}
 	}
@@ -264,6 +249,7 @@ func (pkt *packet) read(s *Session) error {
 }
 
 // resize adjusts the packet's storage to accommodate a body of the given size and header type.
+// When headerSizeAuto is specified, the header type is computed based on packet type.
 func (pkt *packet) resize(size uint32, ht uint8) {
 	buf := make([]byte, fullHeaderSize+size)
 	pkt.header = buf
@@ -287,7 +273,9 @@ func (pkt *packet) resize(size uint32, ht uint8) {
 	}
 }
 
-// write sends a packet.
+// write sends an RTMP packet.
+// Packets are written in chunks which are Session.chunkSize in length (128 bytes in length).
+// We defers sending small audio packets and combine consecutive small audio packets where possible to reduce I/O.
 // When queue is true, we expect a response to this request and cache the method on s.methodCalls.
 func (pkt *packet) write(s *Session, queue bool) error {
 	if pkt.body == nil {
@@ -438,7 +426,6 @@ func (pkt *packet) write(s *Session, queue bool) error {
 	}
 
 	// TODO(kortschak): Rewrite this horrific peice of premature optimisation.
-	// NB: RTMP wants packets in chunks which are 128 bytes by default, but the server may request a different size.
 	s.log(DebugLevel, pkg+"sending packet", "la", s.link.conn.LocalAddr(), "ra", s.link.conn.RemoteAddr(), "size", size)
 	for size+hSize != 0 {
 		if chunkSize > size {
@@ -461,6 +448,7 @@ func (pkt *packet) write(s *Session, queue bool) error {
 		hSize = 0
 
 		if size > 0 {
+			// We are writing the 2nd or subsequent chunk.
 			origIdx -= 1 + cSize
 			hSize = 1 + cSize
 
@@ -486,7 +474,7 @@ func (pkt *packet) write(s *Session, queue bool) error {
 		}
 	}
 
-	// We invoked a remote method
+	// We invoked a remote method,
 	if pkt.packetType == packetTypeInvoke {
 		buf := pkt.body[1:]
 		meth := amf.DecodeString(buf)