Bug 128567

Created attachment 16445 [details]
adds a try - catch statement and displays a KMessageBox::error

I'm gonna deal with this in a different way and on a different place.

SVN commit 547838 by guisson:

Fixed bug with uncaught exception during startup of torrent.

BUG: 128567



 M  +35 -8     queuemanager.cpp  
 M  +11 -1     torrentcontrol.cpp  


--- trunk/extragear/network/ktorrent/libktorrent/torrent/queuemanager.cpp #547837:547838
@@ -162,18 +162,26 @@
 		while (i != downloads.end())
 		{
 			kt::TorrentInterface* tc = *i;
+			const TorrentStats & s = tc->getStats();
 			if (tc->getStats().running)
 			{
-				if(type >= 3)
-					tc->stop(true);
-				else
+				try
 				{
-					if( (tc->getStats().completed && type == 2) || (!tc->getStats().completed && type == 1) )
+					if(type >= 3)
 						tc->stop(true);
+					else if( (s.completed && type == 2) || (!s.completed && type == 1) )
+						tc->stop(true);
 				}
+				catch (bt::Error & err)
+				{
+					QString msg =
+							i18n("Error stopping torrent %1 : %2")
+							.arg(s.torrent_name).arg(err.toString());
+					KMessageBox::error(0,msg,i18n("Error"));
+				}
 			}
 			else //if torrent is not running but it is queued we need to make it user controlled
-				if( (tc->getStats().completed && type == 2) || (!tc->getStats().completed && type == 1) || (type == 3) )
+				if( (s.completed && type == 2) || (!s.completed && type == 1) || (type == 3) )
 					tc->setPriority(0); 
 			i++;
 		}
@@ -441,8 +449,17 @@
 			{
 				TorrentInterface* tc = *it;
 				const TorrentStats & s = tc->getStats();
-				
-				tc->start();
+				try
+				{
+					tc->start();
+				}
+				catch (bt::Error & err)
+				{
+					QString msg =
+							i18n("Error starting torrent %1 : %2")
+							.arg(s.torrent_name).arg(err.toString());
+					KMessageBox::error(0,msg,i18n("Error"));
+				}
 			}
 			
 			delete paused_torrents;
@@ -461,7 +478,17 @@
 				if(s.running)
 				{
 					paused_torrents->append(tc);
-					tc->stop(false);
+					try
+					{
+						tc->stop(false);
+					}
+					catch (bt::Error & err)
+					{
+						QString msg =
+								i18n("Error stopping torrent %1 : %2")
+								.arg(s.torrent_name).arg(err.toString());
+						KMessageBox::error(0,msg,i18n("Error"));
+					}
 				}
 			}
 		}
--- trunk/extragear/network/ktorrent/libktorrent/torrent/torrentcontrol.cpp #547837:547838
@@ -233,10 +233,20 @@
 		if (stats.running)
 			return;
 
-		aboutToBeStarted(this);
 		stats.stopped_by_error = false;
 		io_error = false;
+		try
+		{
+			aboutToBeStarted(this);
+		}
+		catch (Error & err)
+		{
+			// something went wrong when files were recreated, set error and rethrow
+			onIOError(err.toString());
+			throw;
+		}
 		
+		
 		// if the torrent has DHT nodes add them as potential peers to the PeerManager
 		if (tor->getNumDHTNodes() > 0)
 		{

ok, just to inform you, now it crashes again.


Using host libthread_db library "/lib/libthread_db.so.1".
`system-supplied DSO at 0xffffe000' has disappeared; keeping its symbols.
[Thread debugging using libthread_db enabled]
[New Thread 16384 (LWP 20063)]
[KCrash handler]
#6  0xb66ea3e1 in kill () from /lib/libc.so.6
#7  0xb69d9131 in pthread_kill () from /lib/libpthread.so.0
#8  0xb69d94ab in raise () from /lib/libpthread.so.0
#9  0xb66ea174 in raise () from /lib/libc.so.6
#10 0xb66eb64d in abort () from /lib/libc.so.6
#11 0xb688cd97 in __cxa_call_unexpected ()
   from /usr/lib/gcc-lib/i686-pc-linux-gnu/3.3.5-20050130/libstdc++.so.5
#12 0xb688cdd4 in std::terminate ()
   from /usr/lib/gcc-lib/i686-pc-linux-gnu/3.3.5-20050130/libstdc++.so.5
#13 0xb688cf46 in __cxa_throw ()
   from /usr/lib/gcc-lib/i686-pc-linux-gnu/3.3.5-20050130/libstdc++.so.5
#14 0xb7e0f529 in bt::Touch (url=@0xbfc055e0, nothrow=false)
    at /home/jonas/src/ktorrent-svn/libktorrent/util/fileops.cpp:215
#15 0xb7e55920 in bt::MultiFileCache::touch (this=0x84430f8, fpath=
      {static null = {static null = <same as static member of an already seen type>, d = 0x80c0e00, static shared_null = 0x80c0e00}, d = 0x8483fd8, static shared_null = 0x80c0e00}, dnd=false)
    at /home/jonas/src/ktorrent-svn/libktorrent/torrent/multifilecache.cpp:178
#16 0xb7e553ab in bt::MultiFileCache::create (this=0x84430f8)
    at /home/jonas/src/ktorrent-svn/libktorrent/torrent/multifilecache.cpp:144
#17 0xb7e1fa4c in bt::ChunkManager::createFiles (this=0x84833e0)
    at /home/jonas/src/ktorrent-svn/libktorrent/torrent/chunkmanager.cpp:203
#18 0xb7e21eed in bt::ChunkManager::dndMissingFiles (this=0x84833e0)
    at /home/jonas/src/ktorrent-svn/libktorrent/torrent/chunkmanager.cpp:841
#19 0xb7e3bcd7 in bt::TorrentControl::dndMissingFiles (this=0x843a058)
    at /home/jonas/src/ktorrent-svn/libktorrent/torrent/torrentcontrol.cpp:1131
#20 0x08077ba6 in KTorrentCore::aboutToBeStarted (this=0x8289d40, 
    tc=0x843a058)
    at /home/jonas/src/ktorrent-svn/apps/ktorrent/ktorrentcore.cpp:775
#21 0x0807866b in KTorrentCore::qt_invoke (this=0x8289d40, _id=9, 
    _o=0xbfc058e0) at ktorrentcore.moc:233
#22 0xb6e62545 in QObject::activate_signal (this=0x843a058, clist=0x8483bb8, 
    o=0xbfc058e0) at qobject.cpp:2356
#23 0xb7e94866 in kt::TorrentInterface::aboutToBeStarted (this=0x843a058, 
    t0=0x843a058) at torrentinterface.moc:174
#24 0xb7e35f04 in bt::TorrentControl::start (this=0x843a058)
    at /home/jonas/src/ktorrent-svn/libktorrent/torrent/torrentcontrol.cpp:240
#25 0xb7e6a78a in bt::QueueManager::start (this=0x832d4c8, tc=0x843a058, 
    user=true)
    at /home/jonas/src/ktorrent-svn/libktorrent/torrent/queuemanager.cpp:107
#26 0xb7e6b9b1 in bt::QueueManager::orderQueue (this=0x832d4c8)
    at /home/jonas/src/ktorrent-svn/libktorrent/torrent/queuemanager.cpp:398
#27 0x08075b79 in KTorrentCore::loadTorrents (this=0x8289d40)
    at /home/jonas/src/ktorrent-svn/apps/ktorrent/ktorrentcore.cpp:304
#28 0x08061f70 in KTorrent (this=0x80cbff0)
    at /home/jonas/src/ktorrent-svn/apps/ktorrent/ktorrent.cpp:195
#29 0x0807c734 in KTorrentApp::newInstance (this=0xbfc065e0)
    at /home/jonas/src/ktorrent-svn/apps/ktorrent/ktorrentapp.cpp:66
#30 0xb75ab308 in KUniqueApplication::processDelayed (this=0xbfc065e0)
    at /home/jonas/kdesvn/kdelibs/kdecore/kuniqueapplication.cpp:444
#31 0xb75ab74c in KUniqueApplication::qt_invoke (this=0xbfc065e0, _id=18, 
    _o=0x0) at kuniqueapplication.moc:86
#32 0x0807c9f5 in KTorrentApp::qt_invoke (this=0xbfc065e0, _id=18, 
    _o=0xbfc06010) at ktorrentapp.moc:77
#33 0xb6e62545 in QObject::activate_signal (this=0x82324d8, clist=0x81d4d58, 
    o=0xbfc06010) at qobject.cpp:2356
#34 0xb71cb663 in QSignal::signal (this=0x82324d8, t0=@0x8232500)
    at moc_qsignal.cpp:100
#35 0xb6e7fad2 in QSignal::activate (this=0x82324d8) at qsignal.cpp:212
#36 0xb6e87438 in QSingleShotTimer::event (this=0x82324b0) at qtimer.cpp:286
#37 0xb6dfe7a7 in QApplication::internalNotify (this=0xbfc065e0, 
    receiver=0x82324b0, e=0xbfc06340) at qapplication.cpp:2635
#38 0xb6dfdcde in QApplication::notify (this=0xbfc065e0, receiver=0x82324b0, 
    e=0xbfc06340) at qapplication.cpp:2358
#39 0xb74fddfd in KApplication::notify (this=0xbfc065e0, receiver=0x82324b0, 
    event=0xbfc06340)
    at /home/jonas/kdesvn/kdelibs/kdecore/kapplication.cpp:550
#40 0xb7d380a3 in QApplication::sendEvent (receiver=0x0, event=0x6)
    at qapplication.h:496
#41 0xb6deceae in QEventLoop::activateTimers (this=0x81d4eb8)
    at qeventloop_unix.cpp:556
#42 0xb6da3ca1 in QEventLoop::processEvents (this=0x81d4eb8, flags=4)
    at qeventloop_x11.cpp:389
#43 0xb6e12dfd in QEventLoop::enterLoop (this=0x81d4eb8) at qeventloop.cpp:198
#44 0xb6e12d16 in QEventLoop::exec (this=0x81d4eb8) at qeventloop.cpp:145
#45 0xb6dfe913 in QApplication::exec (this=0xbfc065e0)
    at qapplication.cpp:2758
#46 0x0805fe0d in main (argc=7, argv=0xbfc06764)
    at /home/jonas/src/ktorrent-svn/apps/ktorrent/main.cpp:113

Are you sure you have the latest ? It should eventually get caught in queuemanager.cpp around line 107 (#25 in the backtrace)

Yes I am sure, I have revision 547889

I believe the problem is that the exception is thrown from #14 which is inside a slot #20 KTorrentCore::aboutToBeStarted.
Qt3 isn't compiled with exceptions here, and from all I've heard on kde-devel this is normal. This means the exception will never reach the point you want it to be catched at. It just aborts here.

Crap, I was hoping it would work even if Qt was compiled without exception support.

SVN commit 547968 by guisson:

Catch exceptions at a different place, apparently Qt without exception support will make exceptions not work when we hit a stack frame with Qt code.

BUG: 128567



 M  +35 -12    ktorrentcore.cpp  


--- trunk/extragear/network/ktorrent/apps/ktorrent/ktorrentcore.cpp #547967:547968
@@ -756,35 +756,58 @@
 void KTorrentCore::aboutToBeStarted(kt::TorrentInterface* tc)
 {
 	QStringList missing;
-	if (tc->hasMissingFiles(missing))
+	if (!tc->hasMissingFiles(missing))
+		return;
+	
+	
+	if (tc->getStats().multi_file_torrent)
 	{
-		if (tc->getStats().multi_file_torrent)
+		QString msg = i18n("Several data files of the torrent \"%1\" are missing, do you want to recreate them, or do you want to not download them ?").arg(tc->getStats().torrent_name);
+					
+		int ret = KMessageBox::warningYesNoList(0,msg,missing,QString::null,
+				KGuiItem(i18n("Recreate")),KGuiItem(i18n("Do not download")));
+		if (ret == KMessageBox::Yes)
 		{
-			QString msg = i18n("Several data files of the torrent \"%1\" are missing, do you want to recreate them, or do you want to not download them ?").arg(tc->getStats().torrent_name);
-					
-			int ret = KMessageBox::warningYesNoList(0,msg,missing,QString::null,
-					KGuiItem(i18n("Recreate")),KGuiItem(i18n("Do not download")));
-			if (ret == KMessageBox::Yes)
+			try
 			{
 				// recreate them
 				tc->recreateMissingFiles();
 			}
-			else
+			catch (bt::Error & e)
 			{
+				KMessageBox::error(0,i18n("Cannot recreate missing files : %1").arg(e.toString()));
+			}
+		}
+		else
+		{
+			try
+			{
 				// mark them as do not download
 				tc->dndMissingFiles();
 			}
+			catch (bt::Error & e)
+			{
+				KMessageBox::error(0,i18n("Cannot deselect missing files : %1").arg(e.toString()));
+			}
 		}
-		else
+	}
+	else
+	{
+		QString msg = i18n("The file where the data is saved of the torrent \"%1\" is missing, do you want to recreate it ?").arg(tc->getStats().torrent_name);
+		int ret = KMessageBox::warningYesNo(0,msg);
+		if (ret == KMessageBox::Yes)
 		{
-			QString msg = i18n("The file where the data is saved of the torrent \"%1\" is missing, do you want to recreate it ?").arg(tc->getStats().torrent_name);
-			int ret = KMessageBox::warningYesNo(0,msg);
-			if (ret == KMessageBox::Yes)
+			try
 			{
 				tc->recreateMissingFiles();
 			}
+			catch (bt::Error & e)
+			{
+				KMessageBox::error(0,i18n("Cannot recreate data file : %1").arg(e.toString()));
+			}
 		}
 	}
+	
 }
 
 void KTorrentCore::connectSignals(kt::TorrentInterface* tc)

Created attachment 17050 [details]
backtrace when answering "no"

I'm using Ktorrent 2.0rc1, KDE 3.5.3. I am able to consistently crash Ktorrent
by doing the following;

1. Download a file.
2. Remove file using anything but Ktorrent. (konqueror for example)
3. Restart the Ktorrent.
4. You get a dialog asking if you want to recreate the file. If answered "no"
the application crashes. (If answered yes, the file seems to be properly
re-created.)

I decided that this might be a seperate bug on it's own. Filed here; http://bugs.kde.org/show_bug.cgi?id=131142