Properly obtain threading debug information in TDE crash handler

Fix potential TDE crash handler lockup uncer certain circumstances
Enhance crashtest program with three threads

drkonqi/backtrace.cpp

@@ -176,8 +176,22 @@ void BackTrace::slotProcessExited(TDEProcess *proc)
 bool BackTrace::usefulBacktrace()
 {
   // remove crap
-  if( !m_krashconf->removeFromBacktraceRegExp().isEmpty())
+  if( !m_krashconf->removeFromBacktraceRegExp().isEmpty()) {
     m_strBt.replace(TQRegExp( m_krashconf->removeFromBacktraceRegExp()), TQString());
+  }
+
+  // fix threading info output
+  if( !m_krashconf->threadRegExp().isEmpty()) {
+    int pos = -1;
+    TQRegExp threadRegExpression( m_krashconf->threadRegExp());
+    do {
+      threadRegExpression.search(m_strBt);
+      pos = threadRegExpression.pos();
+      if (pos > -1) {
+        m_strBt.insert(threadRegExpression.pos()+1, "==== ");
+      }
+    } while (pos > -1);
+  }
 
   if( m_krashconf->disableChecks())
       return true;
@@ -204,20 +218,32 @@ void BackTrace::processBacktrace()
 {
 	if( !m_krashconf->kcrashRegExp().isEmpty()) {
 		TQRegExp kcrashregexp( m_krashconf->kcrashRegExp());
-		int pos = -1;
+		kcrashregexp.setMinimal(true);
-		while ((pos = kcrashregexp.search( m_strBt )) >= 0) {
+		int pos = 0;
-			pos = kcrashregexp.search( m_strBt );
+		int prevpos = 0;
+		while ((pos = kcrashregexp.search( m_strBt, pos )) >= 0) {
+			if (prevpos == pos) {
+				// Avoid infinite loop
+				// Shouldn't ever get here, but given that this is a crash handler, better safe than sorry!
+				break;
+			}
+			prevpos = pos;
 			if( pos >= 0 ) {
 				int len = kcrashregexp.matchedLength();
 				int nextinfochunkpos = m_strBt.find("====", pos);
 				if (nextinfochunkpos >= 0) {
 					// Trying to delete too much!
-					int chunkpos = pos;
+					int limitedlen = nextinfochunkpos - pos;
-					TQString limitedstrBt = m_strBt.mid(pos, nextinfochunkpos - pos);
+					TQString limitedstrBt = m_strBt.mid(pos, limitedlen);
-					pos = kcrashregexp.search( limitedstrBt ) + chunkpos;
+					int limitedpos = kcrashregexp.search( limitedstrBt );
-					len = kcrashregexp.matchedLength();
+					if (limitedpos >= 0) {
+						len = kcrashregexp.matchedLength();
+					}
+					else {
+						len = 0;
+					}
 				}
-				if (pos >= 0) {
+				if ((pos >= 0) && (len > 0)) {
 					if( m_strBt[ pos ] == '\n' ) {
 						++pos;
 						--len;
@@ -226,6 +252,17 @@ void BackTrace::processBacktrace()
 					m_strBt.insert( pos, TQString::fromLatin1( "[TDECrash handler]\n" ));
 				}
 			}
+			if (pos < 0) {
+				// Avoid infinite loop
+				// Shouldn't ever get here, but given that this is a crash handler, better safe than sorry!
+				break;
+			}
+			pos++;
+			if ((uint)pos >= m_strBt.length()) {
+				// Avoid infinite loop
+				// Shouldn't ever get here, but given that this is a crash handler, better safe than sorry!
+				break;
+			}
 		}
 	}
 	if( !m_krashconf->kcrashRegExpSingle().isEmpty()) {
@@ -242,7 +279,7 @@ void BackTrace::processBacktrace()
 	}
 
 	// Append potentially important hardware information
-	m_strBt.append("\n\n==== (tdehwlib) hardware information ====\n");
+	m_strBt.append("\n==== (tdehwlib) hardware information ====\n");
 	TDEHardwareDevices *hwdevices = TDEGlobal::hardwareDevices();
 	TDEGenericHardwareList hwlist = hwdevices->listAllPhysicalDevices();
 	TDEGenericDevice *hwdevice;
@@ -259,4 +296,14 @@ void BackTrace::processBacktrace()
 			m_strBt.append("\n");
 		}
 	}
+
+	{
+		// Clean up hard to read debug blocks
+		TQRegExp kcrashregexp( "[^\n]\n==== ");
+		kcrashregexp.setMinimal(true);
+		int pos = 0;
+		while ((pos = kcrashregexp.search( m_strBt, pos )) >= 0) {
+			m_strBt.insert(pos+1, "\n");
+		}
+	}
 }

drkonqi/crashtest.cpp

@@ -1,11 +1,28 @@
 // Let's crash.
+#include <unistd.h>
 #include <tdeapplication.h>
 #include <tdeaboutdata.h>
 #include <tdecmdlineargs.h>
+#include <tqthread.h>
+#include <tqtimer.h>
 #include <kdebug.h>
 #include <stdio.h>
 #include <assert.h>
 
+#include "crashtest.h"
+
+void WorkerObject::run()
+{
+	while (1) {
+		sleep(10000);
+	}
+}
+
+#define SET_UP_WORKER(x, y)												\
+	WorkerObject x;													\
+	x.moveToThread(&y);												\
+	TQTimer::singleShot(0, &x, SLOT(run()));
+
 static TDECmdLineOptions options[] =
 {
   { "+crash|malloc|div0|assert", "Type of crash.", 0 },
@@ -74,6 +91,17 @@ int main(int argc, char *argv[])
                        TDEAboutData::License_GPL,
                        "(c) 2000-2002 David Faure, Waldo Bastian");
 
+  // Start 3 threads
+  TQEventLoopThread workerthread0;
+  TQEventLoopThread workerthread1;
+  TQEventLoopThread workerthread2;
+  SET_UP_WORKER(worker0, workerthread0)
+  SET_UP_WORKER(worker1, workerthread1)
+  SET_UP_WORKER(worker2, workerthread2)
+  workerthread0.start();
+  workerthread1.start();
+  workerthread2.start();
+
   TDECmdLineArgs::init(argc, argv, &aboutData);
   TDECmdLineArgs::addCmdLineOptions(options);
 
@@ -90,3 +118,5 @@ int main(int argc, char *argv[])
   level1(crashtype);
   return app.exec();
 }
+
+#include "crashtest.moc"

drkonqi/crashtest.h

@@ -0,0 +1,40 @@
+/*****************************************************************
+ *
+ * Copyright (C) 2013 Timothy Pearson <kb9vqf@pearsoncomputing.net>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *****************************************************************/
+
+#ifndef CRASHTEST_H
+#define CRASHTEST_H
+
+#include <tqobject.h>
+
+class WorkerObject : public TQObject
+{
+	Q_OBJECT
+
+	public slots:
+		void run();
+};
+
+#endif // CRASHTEST_H

drkonqi/debuggers/gdbrc

@@ -158,10 +158,11 @@ Comment[zu]=Umcoshi wamaphutha osekelwe umbhalo osuka kwi-GNU kwikhonsoli
 Exec=konsole -e gdb -nw %execname %pid
 ExecBatch=gdb -nw -n -batch -x %tempfile %execname %pid
 TryExec=gdb
-BacktraceCommand=echo \\n\necho ==== (gdb) bt ====\\n\nbt\necho \\n\\n\necho ==== (gdb) bt full ====\\n\nbt full\necho\\n\\n\necho ==== (gdb) thread apply all bt ====\\n\nthread apply all bt
+BacktraceCommand=echo \\n\necho ==== (gdb) bt ====\\n\nbt\necho \\n\\n\necho ==== (gdb) bt full ====\\n\nbt full\necho\\n\\n\necho ==== (gdb) info thread ====\\n\ninfo thread\necho\\n\\n\necho ==== (gdb) thread apply all bt ====\\n\nthread apply all bt
 RemoveFromBacktraceRegExp=\(no debugging symbols found\)\.\.\.\\n?
 InvalidStackFrameRegExp=\\n#[0-9]+\\s+0x[0-9A-Fa-f]+ \w* \?\?
 FrameRegExp=\\n#[0-9]+\\s+0x[0-9A-Fa-f]+
 NeededInValidBacktraceRegExp=\\n#5
 TDECrashRegExp=\\n#0[ ]*0x[0123456789abcdefABCDEF]+.*<signal handler called>[ ]*\\n
 TDECrashRegExpSingle=\\n0x[0123456789abcdefABCDEF][^\\n]*\\n
+ThreadRegExp=\\nThread [0123456789]

drkonqi/krashconf.cpp

@@ -112,6 +112,7 @@ void KrashConfig :: readConfig()
   m_neededInValidBacktraceRegExp = debuggers.readEntry("NeededInValidBacktraceRegExp");
   m_kcrashRegExp = debuggers.readEntry("TDECrashRegExp");
   m_kcrashRegExpSingle = debuggers.readEntry("TDECrashRegExpSingle");
+  m_threadRegExp = debuggers.readEntry("ThreadRegExp");
 
   TDEConfig preset(TQString::fromLatin1("presets/%1rc").arg(configname),
                  true, false, "appdata");

drkonqi/krashconf.h

@@ -67,6 +67,7 @@ public:
   TQString neededInValidBacktraceRegExp() const { return m_neededInValidBacktraceRegExp; }
   TQString kcrashRegExp() const { return m_kcrashRegExp; }
   TQString kcrashRegExpSingle() const { return m_kcrashRegExpSingle; }
+  TQString threadRegExp() const { return m_threadRegExp; }
   bool showBacktrace() const { return m_showbacktrace; };
   bool showDebugger() const { return m_showdebugger && !m_debugger.isNull(); };
   bool showBugReport() const { return m_showbugreport; };
@@ -110,6 +111,7 @@ private:
   TQString m_neededInValidBacktraceRegExp;
   TQString m_kcrashRegExp;
   TQString m_kcrashRegExpSingle;
+  TQString m_threadRegExp;
 };
 
 #endif