Factor out begin_monitoring_file_size()

[srec] / srec.py

diff --git a/srec.py b/srec.py
index bacc1df5654fbffd2c8a8b4765abcc87e420f0b8..64f2d07e89d4c98c1e93d06892cdc89a035da929 100644 (file)
--- a/srec.py
+++ b/srec.py
@@ -4,10 +4,13 @@
 # under the terms of the GNU General Public License as published by the
 # Free Software Foundation, version 3.
 
+from __future__ import annotations
+
 from dataclasses import dataclass
 from datetime import datetime
 import os
 import subprocess
+import sys
 from typing import Any, Callable
 
 import gi
@@ -19,12 +22,26 @@ from gi.repository import GLib  # nopep8 pylint: disable=wrong-import-position
 
 
 @dataclass
-class Recording:
-    filename: str
+class Stream:
     process: subprocess.Popen[bytes]
 
+    @staticmethod
+    def start(command: list[str]) -> Stream:
+        # pylint: disable=consider-using-with
+        return Stream(process=subprocess.Popen(command, stdin=subprocess.PIPE))
+
+    def stop(self) -> None:
+        stdin = self.process.stdin
+        assert stdin is not None
+        try:
+            stdin.write(b'q')
+            stdin.flush()
+        except BrokenPipeError:
+            print("Stream already stopped?", file=sys.stderr)
+        self.process.wait()
 
-recording: Recording | None = None
+
+recording: Stream | None = None
 
 
 def make_filename() -> str:
@@ -57,13 +74,7 @@ def summarize_size(n: int) -> str:
     return str(n)
 
 
-def on_start_recording(_: Gtk.Button, stack: Gtk.Stack) -> None:
-    global recording  # pylint: disable=global-statement
-    assert recording is None
-
-    filename = make_filename()
-    size_display = find_size_display(stack)
-
+def begin_monitoring_file_size(size_display: Gtk.Label, filename: str) -> None:
     def update_size_display() -> Any:
         try:
             size = summarize_size(os.stat(filename).st_size)
@@ -73,23 +84,24 @@ def on_start_recording(_: Gtk.Button, stack: Gtk.Stack) -> None:
         return GLib.SOURCE_REMOVE if recording is None else GLib.SOURCE_CONTINUE
     GLib.timeout_add_seconds(1, update_size_display)
 
-    command = (['ffmpeg', '-framerate', '25'] + video_source(stack) +
-               ['-f', 'pulse', '-ac', '2', '-i', 'default', filename])
-    # pylint: disable=consider-using-with
-    recording = Recording(
-        filename=filename,
-        process=subprocess.Popen(command, stdin=subprocess.PIPE))
+
+def on_start_recording(_: Gtk.Button, stack: Gtk.Stack) -> None:
+    global recording  # pylint: disable=global-statement
+    assert recording is None
+
+    filename = make_filename()
+    begin_monitoring_file_size(find_size_display(stack), filename)
+
+    recording = Stream.start(
+        ['ffmpeg', '-framerate', '25'] + video_source(stack) +
+        ['-f', 'pulse', '-ac', '2', '-i', 'default', filename])
     stack.set_visible_child_name("recording")
 
 
 def on_stop_recording(_: Gtk.Button, stack: Gtk.Stack) -> None:
     global recording  # pylint: disable=global-statement
     assert recording is not None
-    stdin = recording.process.stdin
-    assert stdin is not None
-    stdin.write(b'q')
-    stdin.flush()
-    recording.process.wait()
+    recording.stop()
     recording = None
     stack.set_visible_child_name("not_recording")
 
@@ -106,7 +118,7 @@ def make_button(label: str, action: Callable[[
 
 
 def make_share_control() -> Gtk.CheckButton:
-    can_share = os.path.exists('/sys/module/v4l2looback')
+    can_share = os.path.exists('/sys/module/v4l2loopback')
     control = Gtk.CheckButton(
         label='Share Webcam', sensitive=can_share, active=can_share)
     control.set_margin_start(20)