Method get_context

pydevd_attach_to_process/winappdbg/thread.py:466–552

Retrieves the execution context (i.e. the registers values) for this thread. @type ContextFlags: int @param ContextFlags: Optional, specify which registers to retrieve. Defaults to C{win32.CONTEXT_ALL} which retrieves all registes for the cu

(self, ContextFlags=None, bSuspend=False)

    # TODO
    # A registers cache could be implemented here.
    def get_context(self, ContextFlags=None, bSuspend=False):
        """
        Retrieves the execution context (i.e. the registers values) for this
        thread.

        @type  ContextFlags: int
        @param ContextFlags: Optional, specify which registers to retrieve.
            Defaults to C{win32.CONTEXT_ALL} which retrieves all registes
            for the current platform.

        @type  bSuspend: bool
        @param bSuspend: C{True} to automatically suspend the thread before
            getting its context, C{False} otherwise.

            Defaults to C{False} because suspending the thread during some
            debug events (like thread creation or destruction) may lead to
            strange errors.

            Note that WinAppDbg 1.4 used to suspend the thread automatically
            always. This behavior was changed in version 1.5.

        @rtype:  dict( str S{->} int )
        @return: Dictionary mapping register names to their values.

        @see: L{set_context}
        """

        # Some words on the "strange errors" that lead to the bSuspend
        # parameter. Peter Van Eeckhoutte and I were working on a fix
        # for some bugs he found in the 1.5 betas when we stumbled upon
        # what seemed to be a deadlock in the debug API that caused the
        # GetThreadContext() call never to return. Since removing the
        # call to SuspendThread() solved the problem, and a few Google
        # searches showed a handful of problems related to these two
        # APIs and Wow64 environments, I decided to break compatibility.
        #
        # Here are some pages about the weird behavior of SuspendThread:
        # http://zachsaw.blogspot.com.es/2010/11/wow64-bug-getthreadcontext-may-return.html
        # http://stackoverflow.com/questions/3444190/windows-suspendthread-doesnt-getthreadcontext-fails

        # Get the thread handle.
        dwAccess = win32.THREAD_GET_CONTEXT
        if bSuspend:
            dwAccess = dwAccess | win32.THREAD_SUSPEND_RESUME
        hThread = self.get_handle(dwAccess)

        # Suspend the thread if requested.
        if bSuspend:
            try:
                self.suspend()
            except WindowsError:
                # Threads can't be suspended when the exit process event
                # arrives, but you can still get the context.
                bSuspend = False

        # If an exception is raised, make sure the thread execution is resumed.
        try:
            if win32.bits == self.get_bits():