From a00550b63862de26ae4d0d8d71172845ba1731d5 Mon Sep 17 00:00:00 2001
From: Jake Lane <me@jakelane.me>
Date: Wed, 18 Jul 2018 13:27:40 +0930
Subject: [PATCH] rtmp: Implemented afmDecodeInt24 and afmDecodeString

---
 rtmp/rtmp.go | 30 +++++++++++++++++++++++-------
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/rtmp/rtmp.go b/rtmp/rtmp.go
index 1d6bcd67..015f9d60 100644
--- a/rtmp/rtmp.go
+++ b/rtmp/rtmp.go
@@ -8,6 +8,7 @@ DESCRIPTION
 AUTHOR
   Saxon Nelson-Milton <saxon@ausocean.org>
   Dan Kortschak <dan@ausocean.org>
+  Jake Lane <jake@ausocean.org>
 
 LICENSE
   rtmp.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean)
@@ -199,11 +200,9 @@ func rtmpWrite(r *C.RTMP, data []byte) int {
 
 			pkt.m_packetType = C.uint8_t(*indxBytePtr(buf, 0))
 			buf = incBytePtr(buf, 1)
-			// TODO: port this
-			pkt.m_nBodySize = C.uint32_t(C.AMF_DecodeInt24((*C.char)(buf)))
+			pkt.m_nBodySize = C.uint32_t(afmDecodeInt24((*byte)(buf)))
 			buf = incBytePtr(buf, 3)
-			// TODO: replace with ported version
-			pkt.m_nTimeStamp = C.uint32_t(C.AMF_DecodeInt24((*C.char)(buf)))
+			pkt.m_nTimeStamp = C.uint32_t(afmDecodeInt24((*byte)(buf)))
 			buf = incBytePtr(buf, 3)
 			pkt.m_nTimeStamp |= C.uint32_t(*indxBytePtr(buf, 0)) << 24
 			buf = incBytePtr(buf, 4)
@@ -231,7 +230,6 @@ func rtmpWrite(r *C.RTMP, data []byte) int {
 			pend = incBytePtr(enc, int(pkt.m_nBodySize))
 
 			if pkt.m_packetType == RTMP_PACKET_TYPE_INFO {
-				// TODO: Port this
 				enc = unsafe.Pointer(afmEncodeString((*byte)(enc), (*byte)(pend), &setDataFrame))
 				pkt.m_nBytesRead = C.uint32_t(math.Abs(float64(uintptr(enc) -
 					uintptr(unsafe.Pointer(pkt.m_body)))))
@@ -269,6 +267,13 @@ func rtmpWrite(r *C.RTMP, data []byte) int {
 	return size + s2
 }
 
+// afmDecodeInt24 decodes data into an unsigned int
+func afmDecodeInt24(data *byte) uint32 {
+	dataPtr := unsafe.Pointer(data)
+
+	return (uint32)(*data)<<16 | *(*uint32)(incBytePtr(dataPtr, 1))<<8 | *(*uint32)(incBytePtr(dataPtr, 2))
+}
+
 func afmEncodeString(output *byte, outend *byte, bv *C.AVal) *byte {
 	outputPtr := unsafe.Pointer(output)
 	outendPtr := unsafe.Pointer(outend)
@@ -533,8 +538,7 @@ func sendPacket(r *C.RTMP, packet *C.RTMPPacket, queue int) int {
 		var method C.AVal
 		var ptr unsafe.Pointer
 		ptr = incBytePtr(unsafe.Pointer(packet.m_body), 1)
-		// TODO: port this
-		C.AMF_DecodeString((*C.char)(ptr), &method)
+		afmDecodeString((*byte)(ptr), &method)
 
 		if debugMode {
 			log.Printf("Invoking %v", method.av_val)
@@ -566,6 +570,18 @@ func sendPacket(r *C.RTMP, packet *C.RTMPPacket, queue int) int {
 	return 1
 }
 
+// afmDecodeString decodes data into a string inside a AVal
+func afmDecodeString(data *byte, bv *C.AVal) {
+	dataPtr := unsafe.Pointer(data)
+	bv.av_len = C.int(C.AMF_DecodeInt16((*C.char)(dataPtr)))
+
+	if bv.av_len > 0 {
+		bv.av_val = (*C.char)(incBytePtr(dataPtr, 2))
+	} else {
+		bv.av_val = nil
+	}
+}
+
 func writeN(r *C.RTMP, buffer unsafe.Pointer, n int) int {
 	ptr := buffer
 	for n > 0 {