Libretro fixes (#211)

libretro/libretro.go

@@ -317,6 +317,14 @@ func (core *Core) APIVersion() uint {
 // Deinit takes care of the library global deinitialization
 func (core *Core) Deinit() {
 	C.bridge_retro_deinit(core.symRetroDeinit)
+	environment = nil
+	videoRefresh = nil
+	audioSample = nil
+	audioSampleBatch = nil
+	inputPoll = nil
+	inputState = nil
+	log = nil
+	getTimeUsec = nil
 }
 
 // Run runs the game for one video frame.
@@ -520,16 +528,22 @@ func coreAudioSampleBatch(buf unsafe.Pointer, frames C.size_t) C.size_t {
 	if audioSampleBatch == nil {
 		return 0
 	}
-	return C.size_t(audioSampleBatch(C.GoBytes(buf, C.int(4096)), int32(frames)))
+	return C.size_t(audioSampleBatch(C.GoBytes(buf, C.int(4*int(frames))), int32(frames)))
 }
 
 //export coreLog
 func coreLog(level C.enum_retro_log_level, msg *C.char) {
+	if log == nil {
+		return
+	}
 	log(uint32(level), C.GoString(msg))
 }
 
 //export coreGetTimeUsec
 func coreGetTimeUsec() C.uint64_t {
+	if getTimeUsec == nil {
+		return 0
+	}
 	return C.uint64_t(getTimeUsec())
 }