split finalizer for stream and decoder

decoder.go

@@ -7,6 +7,7 @@ package rtsp
 import "C"
 import (
 	"fmt"
+	"runtime"
 	"unsafe"
 )
 
@@ -26,6 +27,8 @@ func decodeAVPacket(packet *C.AVPacket) (data []byte) {
 
 func newDecoder(cstream *C.AVStream) (*decoder, error) {
 	decoder := &decoder{index: int(cstream.index)}
+	runtime.SetFinalizer(decoder, freeDecoder)
+
 	decoder.swrContext = nil
 	decoder.codecCtx = C.avcodec_alloc_context3(nil)
 	C.avcodec_parameters_to_context(decoder.codecCtx, cstream.codecpar)
@@ -41,6 +44,21 @@ func newDecoder(cstream *C.AVStream) (*decoder, error) {
 	return decoder, nil
 }
 
+func freeDecoder(decoder *decoder) {
+	if decoder.codecCtx != nil {
+		C.avcodec_close(decoder.codecCtx)
+		C.av_free(unsafe.Pointer(decoder.codecCtx))
+		decoder.codecCtx = nil
+	}
+	if decoder.codec != nil {
+		decoder.codec = nil
+	}
+	if decoder.swrContext != nil {
+		C.swr_close(decoder.swrContext)
+		C.swr_free(&decoder.swrContext)
+	}
+}
+
 func (decoder *decoder) Decode(packet *C.AVPacket) (pkt *Packet, err error) {
 	pkt = &Packet{}
 

stream.go

@@ -41,34 +41,12 @@ func free(stream *Stream) {
 	if stream.formatCtx != nil {
 		C.avformat_free_context(stream.formatCtx)
 		stream.formatCtx = nil
-
 	}
 
 	if stream.dictionary != nil {
 		C.av_dict_free(&stream.dictionary)
 		stream.dictionary = nil
 	}
-
-	for _, decoder := range stream.decoders {
-		if decoder != nil {
-			if decoder.codecCtx != nil {
-				C.avcodec_close(decoder.codecCtx)
-				C.av_free(unsafe.Pointer(decoder.codecCtx))
-				decoder.codecCtx = nil
-			}
-			if decoder.codec != nil {
-				decoder.codec = nil
-			}
-
-			if decoder.swrContext != nil {
-				C.swr_close(decoder.swrContext)
-				C.swr_free(&decoder.swrContext)
-			}
-
-			decoder = nil
-		}
-	}
-	stream.decoders = nil
 }
 
 func (stream *Stream) Setup(t Type) (err error) {