GDB Cheatsheet

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class DebugPrintingBreakpoint(gdb.Breakpoint):
    debugging_IDs = frozenset({37, 153, 420})
    def stop(self):
        top = gdb.newest_frame()
        someVector = top.read_var('aVectorVar')
        # Access the begin() & end() pointer of std::vector in GNU Standard C++ lib
        first = someVector['_M_impl']['_M_start']
        last = someVector['_M_impl']['_M_finish']
        values = []
        while first != last:
            values.append(int(first.dereference()['intID']))
            first = first + 1
        if not set(values) & debugging_IDs:
            return False # skip: none of the items we're looking for can be found by ID in the vector on the stack
        print("Found other accompanying IDs: {}".format(values))
        return True # drop to gdb's prompt
# Ensure shared libraries are loaded already
gdb.execute("start")
# Set our breakpoint, which happens to reside in some shared lib, hence the "start" previously
DebugPrintingBreakpoint("source.cpp:42")
gdb.execute("continue")

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def exit_handler (event):
    print ("event type: exit")
    if hasattr (event, 'exit_code'):
        print ("exit code: %d" % (event.exit_code))
    else:
        print ("exit code not available")

gdb.events.exited.connect (exit_handler)

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def signal_stop_handler (event):
    if (isinstance (event, gdb.StopEvent)):
        print ("event type: stop")
        with open("gdb_status.txt", "w") as f:
            f.write("Stopped\n")
        f.close()
    if (isinstance (event, gdb.SignalEvent)):
        print ("stop reason: signal")
        print ("stop signal: %s" % (event.stop_signal))
        if ( event.inferior_thread is not None) :
            print ("thread num: %s" % (event.inferior_thread.num))

gdb.events.stop.connect(signal_stop_handler)