Detect when a daemon is already running in the same config folder.

When the gtkui is run in classic mode with an already running daemon 
process, prompt the user to turn off classic mode or exit.

deluge/core/daemon.py

@@ -1,7 +1,7 @@
 #
 # daemon.py
 #
-# Copyright (C) 2007 Andrew Resch <andrewresch@gmail.com>
+# Copyright (C) 2007-2009 Andrew Resch <andrewresch@gmail.com>
 #
 # Deluge is free software.
 #
@@ -31,8 +31,8 @@
 #    this exception statement from your version. If you delete this exception
 #    statement from all source files in the program, then also delete it here.
 #
-#
 
+import os
 import gettext
 import locale
 import pkg_resources
@@ -44,9 +44,50 @@ import deluge.configmanager
 import deluge.common
 from deluge.core.rpcserver import RPCServer, export
 from deluge.log import LOG as log
+import deluge.error
 
 class Daemon(object):
     def __init__(self, options=None, args=None, classic=False):
+        # Check for another running instance of the daemon
+        if os.path.isfile(deluge.configmanager.get_config_dir("deluged.pid")):
+            # Get the PID and the port of the supposedly running daemon
+            (pid, port) = open(deluge.configmanager.get_config_dir("deluged.pid")).read().strip().split(";")
+            pid = int(pid)
+            port = int(port)
+
+            def process_running(pid):
+                if deluge.common.windows_check():
+                    # Do some fancy WMI junk to see if the PID exists in Windows
+                    from win32com.client import GetObject
+                    def get_proclist():
+                        WMI = GetObject('winmgmts:')
+                        processes = WMI.InstancesOf('Win32_Process')
+                        return [process.Properties_('ProcessID').Value for process in processes]
+                    return pid in get_proclist()
+                else:
+                    # We can just use os.kill on UNIX to test if the process is running
+                    try:
+                        os.kill(pid, 0)
+                    except OSError:
+                        return False
+                    else:
+                        return True
+
+            if process_running(pid):
+                # Ok, so a process is running with this PID, let's make doubly-sure
+                # it's a deluged process by trying to open a socket to it's port.
+                import socket
+                s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+                try:
+                    s.connect(("127.0.0.1", port))
+                except socket.error:
+                    # Can't connect, so it must not be a deluged process..
+                    pass
+                else:
+                    # This is a deluged!
+                    s.close()
+                    raise deluge.error.DaemonRunningError("There is a deluge daemon running with this config directory!")
+
         # Initialize gettext
         try:
             locale.setlocale(locale.LC_ALL, '')
@@ -77,8 +118,6 @@ class Daemon(object):
             SetConsoleCtrlHandler(win_handler)
 
         version = deluge.common.get_version()
-        if deluge.common.get_revision():
-            version = version + "r" + deluge.common.get_revision()
 
         log.info("Deluge daemon %s", version)
         log.debug("options: %s", options)
@@ -108,6 +147,11 @@ class Daemon(object):
         # Make sure we start the PreferencesManager first
         component.start("PreferencesManager")
 
+        # Write out a pid file all the time, we use this to see if a deluged is running
+        # We also include the running port number to do an additional test
+        open(deluge.configmanager.get_config_dir("deluged.pid"), "wb").write(
+            "%s;%s\n" % (os.getpid(), options.port if options.port else 58846))
+
         if not classic:
             component.start()
             try:
@@ -117,6 +161,12 @@ class Daemon(object):
 
     @export()
     def shutdown(self, *args, **kwargs):
+        try:
+            os.remove(deluge.configmanager.get_config_dir("deluged.pid"))
+        except Exception, e:
+            log.exception(e)
+            log.error("Error removing deluged.pid!")
+
         component.shutdown()
         try:
             reactor.stop()

deluge/error.py

@@ -43,3 +43,5 @@ class DelugeError(Exception):
 class NoCoreError(DelugeError):
     pass
 
+class DaemonRunningError(DelugeError):
+    pass

deluge/ui/gtkui/dialogs.py

@@ -0,0 +1,85 @@
+#
+# dialogs.py
+#
+# Copyright (C) 2009 Andrew Resch <andrewresch@gmail.com>
+#
+# Deluge is free software.
+#
+# You may 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.
+#
+# deluge 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 deluge.    If not, write to:
+# 	The Free Software Foundation, Inc.,
+# 	51 Franklin Street, Fifth Floor
+# 	Boston, MA  02110-1301, USA.
+#
+#    In addition, as a special exception, the copyright holders give
+#    permission to link the code of portions of this program with the OpenSSL
+#    library.
+#    You must obey the GNU General Public License in all respects for all of
+#    the code used other than OpenSSL. If you modify file(s) with this
+#    exception, you may extend this exception to your version of the file(s),
+#    but you are not obligated to do so. If you do not wish to do so, delete
+#    this exception statement from your version. If you delete this exception
+#    statement from all source files in the program, then also delete it here.
+#
+
+import gtk
+import deluge.component as component
+
+class YesNoDialog(gtk.Dialog):
+    """
+    Displays a dialog asking the user to select Yes or No to a question.
+
+    When run(), it will return either a gtk.RESPONSE_YES or a gtk.RESPONSE_NO.
+
+    """
+    def __init__(self, header, text, parent=None):
+        """
+        :param header: str, the header portion of the dialog, try to keep it short and to the point
+        :param text: str, the body of the dialog, this can be longer with a more
+            thorough explanation of the question
+        :param parent: gtkWindow, the parent window, if None it will default to the
+            MainWindow
+        """
+        super(YesNoDialog, self).__init__(
+            title="",
+            parent=parent if parent else component.get("MainWindow").window,
+            flags=gtk.DIALOG_MODAL | gtk.DIALOG_DESTROY_WITH_PARENT | gtk.DIALOG_NO_SEPARATOR,
+            buttons=(gtk.STOCK_YES, gtk.RESPONSE_YES, gtk.STOCK_NO, gtk.RESPONSE_NO))
+
+        # XXX: All of this stuff should be moved to a base dialog class..
+        self.set_border_width(5)
+        self.set_default_size(200, 100)
+        hbox = gtk.HBox(spacing=5)
+        image = gtk.Image()
+        image.set_from_stock(gtk.STOCK_DIALOG_QUESTION, gtk.ICON_SIZE_DIALOG)
+        image.set_alignment(0.5, 0.0)
+        hbox.pack_start(image, False, False)
+        vbox = gtk.VBox(spacing=5)
+        label = gtk.Label("<b><big>" + header + "</big></b>")
+        label.set_use_markup(True)
+        label.set_alignment(0.0, 0.5)
+        label.set_line_wrap(True)
+        vbox.pack_start(label, False, False)
+        tlabel = gtk.Label(text)
+        tlabel.set_use_markup(True)
+        tlabel.set_line_wrap(True)
+        tlabel.set_alignment(0.0, 0.5)
+        vbox.pack_start(tlabel, False, False)
+        hbox.pack_start(vbox, False, False)
+        self.vbox.pack_start(hbox, False, False)
+        self.vbox.show_all()
+
+    def run(self):
+        response = super(YesNoDialog, self).run()
+        self.destroy()
+        return response

deluge/ui/gtkui/gtkui.py

@@ -1,7 +1,7 @@
 #
 # gtkui.py
 #
-# Copyright (C) 2007 Andrew Resch <andrewresch@gmail.com>
+# Copyright (C) 2007-2009 Andrew Resch <andrewresch@gmail.com>
 #
 # Deluge is free software.
 #
@@ -62,11 +62,13 @@ from connectionmanager import ConnectionManager
 from pluginmanager import PluginManager
 from ipcinterface import IPCInterface
 from deluge.ui.tracker_icons import TrackerIcons
-
 from queuedtorrents import QueuedTorrents
 from addtorrentdialog import AddTorrentDialog
+import dialogs
+
 import deluge.configmanager
 import deluge.common
+import deluge.error
 
 DEFAULT_PREFS = {
     "classic_mode": True,
@@ -232,9 +234,24 @@ class GtkUI:
     def _on_reactor_start(self):
         log.debug("_on_reactor_start")
         if self.config["classic_mode"]:
-            client.start_classic_mode()
+            try:
-            component.start()
+                client.start_classic_mode()
-            return
+            except deluge.error.DaemonRunningError:
+                response = dialogs.YesNoDialog(
+                    "Turn off Classic Mode?",
+                    "It appears that a Deluge daemon process (deluged) is already running.\n\n\
+You will either need to stop the daemon or turn off Classic Mode to continue.").run()
+
+                self.started_in_classic = False
+                if response != gtk.RESPONSE_YES:
+                    # The user does not want to turn Classic Mode off, so just quit
+                    reactor.stop()
+                    return
+                # Turning off classic_mode
+                self.config["classic_mode"] = False
+            else:
+                component.start()
+                return
 
         # Autoconnect to a host
         if self.config["autoconnect"]:
@@ -250,7 +267,6 @@ class GtkUI:
             self.connectionmanager.show()
 
 
-
     def __on_disconnect(self):
         """
         Called when disconnected from the daemon.  We basically just stop all