Fixed possible loss of reference to thread objects

Use of manual reference counting in order to prevent the freeing of a YtDlp objet with a running thread.

yt-dlp/downloader.gd

@@ -1,3 +1,4 @@
+# warning-ignore-all:return_value_discarded
 extends Reference
 
 signal download_completed
@@ -31,12 +32,10 @@ func download(url: String, file_path: String = "user://") -> void:
 	var http_client := HTTPClient.new()
 
 	print("[downloader] Connecting to %s" % host)
-	# warning-ignore:return_value_discarded
 	http_client.connect_to_host(host, -1, true)
 
 	# Connection to the host
 	while http_client.get_status() in [HTTPClient.STATUS_CONNECTING, HTTPClient.STATUS_RESOLVING]:
-		# warning-ignore:return_value_discarded
 		http_client.poll()
 		yield(Engine.get_main_loop(), "idle_frame")
 
@@ -47,12 +46,10 @@ func download(url: String, file_path: String = "user://") -> void:
 		return
 
 	print("[downloader] Requesting resource at %s" % path)
-	# warning-ignore:return_value_discarded
 	http_client.request(HTTPClient.METHOD_GET, path, _headers)
 
 	# Request the resource
 	while http_client.get_status() == HTTPClient.STATUS_REQUESTING:
-		# warning-ignore:return_value_discarded
 		http_client.poll()
 		yield(Engine.get_main_loop(), "idle_frame")
 
@@ -77,13 +74,11 @@ func download(url: String, file_path: String = "user://") -> void:
 
 func _store_body_to_file(http_client: HTTPClient, file_path: String) -> void:
 	var file: File = File.new()
-	# warning-ignore:return_value_discarded
 	file.open(file_path, File.WRITE)
 
 	var percentage_loaded: float = 0.0
 
 	while http_client.get_status() == HTTPClient.STATUS_BODY:
-		# warning-ignore:return_value_discarded
 		http_client.poll()
 		file.store_buffer(http_client.read_response_body_chunk())
 

yt-dlp/yt_dlp.gd

@@ -1,10 +1,11 @@
+# warning-ignore-all:return_value_discarded
 class_name YtDlp
 extends Reference
 
 
 signal ready
 signal download_completed
-signal _update_complete
+signal _update_completed
 
 enum Video {MP4, WEBM}
 enum Audio {AAC, FLAC, MP3, M4A, OPUS, VORBIS, WAV}
@@ -21,11 +22,11 @@ const ffmpeg_sources: Dictionary = {
 }
 
 var _downloader: Downloader
-var _thread: Thread
-var _ready: bool = false
+var _thread: Thread = Thread.new()
+var _is_ready: bool = false
 
 
-func _init():
+func _init() -> void:
 	print("[yt-dlp] Downloading the latest yt-dlp version")
 
 	_downloader = Downloader.new()
@@ -37,34 +38,34 @@ func _init():
 		_downloader.download(yt_dlp_sources[OS.get_name()], "user://%s" % executable_name)
 		yield(_downloader, "download_completed")
 	else:
-		_thread = Thread.new()
-		# warning-ignore:return_value_discarded
 		_thread.start(self, "_update_yt_dlp", [executable_name])
-		yield(self, "_update_complete")
+		yield(self, "_update_completed")
 		# Waits for the next idle frame to join thread
 		yield(Engine.get_main_loop(), "idle_frame") 
 		_thread.wait_to_finish()
 
 	if OS.get_name() == "Windows":
 		yield(_setup_ffmpeg(), "completed")
 	else:
-		# warning-ignore:return_value_discarded
 		OS.execute("chmod", PoolStringArray(["+x", OS.get_user_data_dir() + "/yt-dlp"]))
 
 	print("[yt-dlp] Ready!")
-	_ready = true
+	_is_ready = true
 	emit_signal("ready")
 
 
 func download(url: String, destination: String, file_name: String, convert_to_audio: bool = false,
-			video_format: int = Video.WEBM, audio_format: int = Audio.VORBIS) -> void:
+		video_format: int = Video.WEBM, audio_format: int = Audio.VORBIS) -> void:
 
 	if destination[-1] != '/':
 		destination += '/'
 
-	if _ready:
-		_thread = Thread.new()
-		# warning-ignore:return_value_discarded
+	if _is_ready:
+		_is_ready = false
+
+		# Increment the reference count while the thread is running
+		reference()
+
 		_thread.start(self, "_execute_on_thread",
 				[url, destination, file_name, convert_to_audio, video_format, audio_format])
 	else:
@@ -85,10 +86,8 @@ func _setup_ffmpeg() -> void:
 
 
 func _update_yt_dlp(arguments: Array) -> void:
-	# warning-ignore:return_value_discarded
 	OS.execute("%s/%s" % [OS.get_user_data_dir(), arguments[0]], ["--update"])
-	emit_signal("_update_complete")
-	return
+	emit_signal("_update_completed")
 
 
 func _execute_on_thread(arguments: Array) -> void:
@@ -127,7 +126,15 @@ func _execute_on_thread(arguments: Array) -> void:
 	options_and_arguments.append_array(["--no-continue", "-o", file_path, url])
 
 	var output: Array = []
-
-	# warning-ignore:return_value_discarded
 	OS.execute(executable, options_and_arguments, true, output)
+
+	call_deferred("_thread_finished")
+
+
+func _thread_finished():
 	emit_signal("download_completed")
+	_thread.wait_to_finish()
+	_is_ready = true
+
+	# Decrement the reference count once the thread is done
+	unreference()