Refactor all of the threading.Threads into QThreads, and quit them all when canceling the server. When canceling the compression thread, specifically mass a cancel message into the Web and ZipWriter objects to make the bail out on compression early

onionshare_gui/share_mode/__init__.py

@@ -17,7 +17,6 @@ GNU General Public License for more details.
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 """
-import threading
 import os
 from PyQt5 import QtCore, QtWidgets, QtGui
 
@@ -28,6 +27,7 @@ from onionshare.web import Web
 
 from .file_selection import FileSelection
 from .downloads import Downloads
+from .threads import CompressThread
 from ..mode import Mode
 from ..widgets import Alert
 
@@ -39,6 +39,9 @@ class ShareMode(Mode):
         """
         Custom initialization for ReceiveMode.
         """
+        # Threads start out as None
+        self.compress_thread = None
+
         # Create the Web object
         self.web = Web(self.common, True, False)
 
@@ -161,28 +164,13 @@ class ShareMode(Mode):
         self._zip_progress_bar.total_files_size = ShareMode._compute_total_size(self.filenames)
         self.status_bar.insertWidget(0, self._zip_progress_bar)
 
-        # Prepare the files for sending in a new thread
-        def finish_starting_server(self):
-            # Prepare files to share
-            def _set_processed_size(x):
-                if self._zip_progress_bar != None:
-                    self._zip_progress_bar.update_processed_size_signal.emit(x)
-
-            try:
-                self.web.set_file_info(self.filenames, processed_size_callback=_set_processed_size)
-                self.app.cleanup_filenames.append(self.web.zip_filename)
-
-                # Only continue if the server hasn't been canceled
-                if self.server_status.status != self.server_status.STATUS_STOPPED:
-                    self.starting_server_step3.emit()
-                    self.start_server_finished.emit()
-            except OSError as e:
-                self.starting_server_error.emit(e.strerror)
-                return
-
-        t = threading.Thread(target=finish_starting_server, kwargs={'self': self})
-        t.daemon = True
-        t.start()
+        # prepare the files for sending in a new thread
+        self.compress_thread = CompressThread(self)
+        self.compress_thread.success.connect(self.starting_server_step3.emit)
+        self.compress_thread.success.connect(self.start_server_finished.emit)
+        self.compress_thread.error.connect(self.starting_server_error.emit)
+        self.server_status.server_canceled.connect(self.compress_thread.cancel)
+        self.compress_thread.start()
 
     def start_server_step3_custom(self):
         """
@@ -222,6 +210,15 @@ class ShareMode(Mode):
         self.update_downloads_in_progress()
         self.file_selection.file_list.adjustSize()
 
+    def cancel_server_custom(self):
+        """
+        Stop the compression thread on cancel
+        """
+        if self.compress_thread:
+            self.common.log('OnionShareGui', 'cancel_server: quitting compress thread')
+            self.compress_thread.cancel()
+            self.compress_thread.quit()
+
     def handle_tor_broke_custom(self):
         """
         Connection to Tor broke.

onionshare_gui/share_mode/threads.py

@@ -0,0 +1,60 @@
+# -*- coding: utf-8 -*-
+"""
+OnionShare | https://onionshare.org/
+
+Copyright (C) 2014-2018 Micah Lee <micah@micahflee.com>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+from PyQt5 import QtCore
+
+
+class CompressThread(QtCore.QThread):
+    """
+    Compresses files to be shared
+    """
+    success = QtCore.pyqtSignal()
+    error = QtCore.pyqtSignal(str)
+
+    def __init__(self, mode):
+        super(CompressThread, self).__init__()
+        self.mode = mode
+        self.mode.common.log('CompressThread', '__init__')
+
+    # prepare files to share
+    def set_processed_size(self, x):
+        if self.mode._zip_progress_bar != None:
+            self.mode._zip_progress_bar.update_processed_size_signal.emit(x)
+
+    def run(self):
+        self.mode.common.log('CompressThread', 'run')
+
+        try:
+            if self.mode.web.set_file_info(self.mode.filenames, processed_size_callback=self.set_processed_size):
+                self.success.emit()
+            else:
+                # Cancelled
+                pass
+
+            self.mode.app.cleanup_filenames.append(self.mode.web.zip_filename)
+        except OSError as e:
+            self.error.emit(e.strerror)
+
+    def cancel(self):
+        self.mode.common.log('CompressThread', 'cancel')
+
+        # Let the Web and ZipWriter objects know that we're canceling compression early
+        self.mode.web.cancel_compression = True
+        if self.mode.web.zip_writer:
+            self.mode.web.zip_writer.cancel_compression = True