Tried to fix the CTRL-C problem (https://github.com/ipython/ipython/pull/742) and take other comments/typos into account

IPython/lib/inputhook.py

@@ -1,522 +1,585 b''
 # coding: utf-8
 """
 Inputhook management for GUI event loop integration.
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2009  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import ctypes
 import sys
 import warnings
 
 #-----------------------------------------------------------------------------
 # Constants
 #-----------------------------------------------------------------------------
 
 # Constants for identifying the GUI toolkits.
 GUI_WX = 'wx'
 GUI_QT = 'qt'
 GUI_QT4 = 'qt4'
 GUI_GTK = 'gtk'
 GUI_TK = 'tk'
 GUI_OSX = 'osx'
 GUI_GLUT = 'glut'
 GUI_PYGLET = 'pyglet'
 
 #-----------------------------------------------------------------------------
 # Utility classes
 #-----------------------------------------------------------------------------
 
 
 #-----------------------------------------------------------------------------
 # Main InputHookManager class
 #-----------------------------------------------------------------------------
 
 
 class InputHookManager(object):
     """Manage PyOS_InputHook for different GUI toolkits.
 
     This class installs various hooks under ``PyOSInputHook`` to handle
     GUI event loop integration.
     """
     
     def __init__(self):
         self.PYFUNC = ctypes.PYFUNCTYPE(ctypes.c_int)
         self._apps = {}
         self._reset()
 
     def _reset(self):
         self._callback_pyfunctype = None
         self._callback = None
         self._installed = False
         self._current_gui = None
 
     def get_pyos_inputhook(self):
         """Return the current PyOS_InputHook as a ctypes.c_void_p."""
         return ctypes.c_void_p.in_dll(ctypes.pythonapi,"PyOS_InputHook")
 
     def get_pyos_inputhook_as_func(self):
         """Return the current PyOS_InputHook as a ctypes.PYFUNCYPE."""
         return self.PYFUNC.in_dll(ctypes.pythonapi,"PyOS_InputHook")
 
     def set_inputhook(self, callback):
         """Set PyOS_InputHook to callback and return the previous one."""
         self._callback = callback
         self._callback_pyfunctype = self.PYFUNC(callback)
         pyos_inputhook_ptr = self.get_pyos_inputhook()
         original = self.get_pyos_inputhook_as_func()
         pyos_inputhook_ptr.value = \
             ctypes.cast(self._callback_pyfunctype, ctypes.c_void_p).value
         self._installed = True
         return original
 
     def clear_inputhook(self, app=None):
         """Set PyOS_InputHook to NULL and return the previous one.
 
         Parameters
         ----------
         app : optional, ignored
           This parameter is allowed only so that clear_inputhook() can be
           called with a similar interface as all the ``enable_*`` methods.  But
           the actual value of the parameter is ignored.  This uniform interface
           makes it easier to have user-level entry points in the main IPython
           app like :meth:`enable_gui`."""
         pyos_inputhook_ptr = self.get_pyos_inputhook()
         original = self.get_pyos_inputhook_as_func()
         pyos_inputhook_ptr.value = ctypes.c_void_p(None).value
         self._reset()
         return original
 
     def clear_app_refs(self, gui=None):
         """Clear IPython's internal reference to an application instance.
 
         Whenever we create an app for a user on qt4 or wx, we hold a
         reference to the app.  This is needed because in some cases bad things
         can happen if a user doesn't hold a reference themselves.  This
         method is provided to clear the references we are holding.
 
         Parameters
         ----------
         gui : None or str
             If None, clear all app references.  If ('wx', 'qt4') clear
             the app for that toolkit.  References are not held for gtk or tk
             as those toolkits don't have the notion of an app.
         """
         if gui is None:
             self._apps = {}
         elif self._apps.has_key(gui):
             del self._apps[gui]
 
     def enable_wx(self, app=None):
         """Enable event loop integration with wxPython.
 
         Parameters
         ----------
         app : WX Application, optional.
             Running application to use.  If not given, we probe WX for an
             existing application object, and create a new one if none is found.
 
         Notes
         -----
         This methods sets the ``PyOS_InputHook`` for wxPython, which allows
         the wxPython to integrate with terminal based applications like
         IPython.
 
         If ``app`` is not given we probe for an existing one, and return it if
         found.  If no existing app is found, we create an :class:`wx.App` as
         follows::
 
             import wx
             app = wx.App(redirect=False, clearSigInt=False)
         """
         from IPython.lib.inputhookwx import inputhook_wx
         self.set_inputhook(inputhook_wx)
         self._current_gui = GUI_WX
         import wx
         if app is None:
             app = wx.GetApp()
         if app is None:
             app = wx.App(redirect=False, clearSigInt=False)
         app._in_event_loop = True
         self._apps[GUI_WX] = app
         return app
 
     def disable_wx(self):
         """Disable event loop integration with wxPython.
 
         This merely sets PyOS_InputHook to NULL.
         """
         if self._apps.has_key(GUI_WX):
             self._apps[GUI_WX]._in_event_loop = False
         self.clear_inputhook()
 
     def enable_qt4(self, app=None):
         """Enable event loop integration with PyQt4.
         
         Parameters
         ----------
         app : Qt Application, optional.
             Running application to use.  If not given, we probe Qt for an
             existing application object, and create a new one if none is found.
 
         Notes
         -----
         This methods sets the PyOS_InputHook for PyQt4, which allows
         the PyQt4 to integrate with terminal based applications like
         IPython.
 
         If ``app`` is not given we probe for an existing one, and return it if
         found.  If no existing app is found, we create an :class:`QApplication`
         as follows::
 
             from PyQt4 import QtCore
             app = QtGui.QApplication(sys.argv)
         """
         from IPython.external.qt_for_kernel import QtCore, QtGui
 
         if 'pyreadline' in sys.modules:
             # see IPython GitHub Issue #281 for more info on this issue
             # Similar intermittent behavior has been reported on OSX,
             # but not consistently reproducible
             warnings.warn("""PyReadline's inputhook can conflict with Qt, causing delays
             in interactive input. If you do see this issue, we recommend using another GUI
             toolkit if you can, or disable readline with the configuration option
             'TerminalInteractiveShell.readline_use=False', specified in a config file or
             at the command-line""",
             RuntimeWarning)
         
         # PyQt4 has had this since 4.3.1.  In version 4.2, PyOS_InputHook
         # was set when QtCore was imported, but if it ever got removed,
         # you couldn't reset it.  For earlier versions we can
         # probably implement a ctypes version.
         try:
             QtCore.pyqtRestoreInputHook()
         except AttributeError:
             pass
 
         self._current_gui = GUI_QT4
         if app is None:
             app = QtCore.QCoreApplication.instance()
         if app is None:
             app = QtGui.QApplication([" "])
         app._in_event_loop = True
         self._apps[GUI_QT4] = app
         return app
 
     def disable_qt4(self):
         """Disable event loop integration with PyQt4.
 
         This merely sets PyOS_InputHook to NULL.
         """
         if self._apps.has_key(GUI_QT4):
             self._apps[GUI_QT4]._in_event_loop = False
         self.clear_inputhook()
 
     def enable_gtk(self, app=None):
         """Enable event loop integration with PyGTK.
 
         Parameters
         ----------
         app : ignored
            Ignored, it's only a placeholder to keep the call signature of all
            gui activation methods consistent, which simplifies the logic of
            supporting magics.
 
         Notes
         -----
         This methods sets the PyOS_InputHook for PyGTK, which allows
         the PyGTK to integrate with terminal based applications like
         IPython.
         """
         import gtk
         try:
             gtk.set_interactive(True)
             self._current_gui = GUI_GTK
         except AttributeError:
             # For older versions of gtk, use our own ctypes version
             from IPython.lib.inputhookgtk import inputhook_gtk
             self.set_inputhook(inputhook_gtk)
             self._current_gui = GUI_GTK
 
     def disable_gtk(self):
         """Disable event loop integration with PyGTK.
         
         This merely sets PyOS_InputHook to NULL.
         """
         self.clear_inputhook()
 
     def enable_tk(self, app=None):
         """Enable event loop integration with Tk.
 
         Parameters
         ----------
         app : toplevel :class:`Tkinter.Tk` widget, optional.
             Running toplevel widget to use.  If not given, we probe Tk for an
             existing one, and create a new one if none is found.
 
         Notes
         -----
         If you have already created a :class:`Tkinter.Tk` object, the only
         thing done by this method is to register with the
         :class:`InputHookManager`, since creating that object automatically
         sets ``PyOS_InputHook``.
         """
         self._current_gui = GUI_TK
         if app is None:
             import Tkinter
             app = Tkinter.Tk()
             app.withdraw()
             self._apps[GUI_TK] = app
             return app
 
     def disable_tk(self):
         """Disable event loop integration with Tkinter.
         
         This merely sets PyOS_InputHook to NULL.
         """
         self.clear_inputhook()
 
-
-<<<<<<< HEAD
-
-    def enable_pyglet(self, app=None):
-        """Enable event loop integration with pyglet.
-=======
     def enable_glut(self, app=None):
         """Enable event loop integration with GLUT.
->>>>>>> Added code for the GLUT interactive session
 
         Parameters
         ----------
         app : ignored
            Ignored, it's only a placeholder to keep the call signature of all
            gui activation methods consistent, which simplifies the logic of
            supporting magics.
 
         Notes
         -----
-<<<<<<< HEAD
-        This methods sets the ``PyOS_InputHook`` for pyglet, which allows
-        pyglet to integrate with terminal based applications like
-        IPython.
-
-        """
-        import pyglet
-        from IPython.lib.inputhookpyglet import inputhook_pyglet
-        self.set_inputhook(inputhook_pyglet)
-        self._current_gui = GUI_PYGLET
-        return app
-
-    def disable_pyglet(self):
-        """Disable event loop integration with pyglet.
 
-        This merely sets PyOS_InputHook to NULL.
-        """
-=======
-        This methods sets the PyOS_InputHook for GLUT, which allows
-        the GLUT to integrate with terminal based applications like
-        IPython.
+        This methods sets the PyOS_InputHook for GLUT, which allows the GLUT to
+        integrate with terminal based applications like IPython. Due to GLUT
+        limitations, it is currently not possible to start the event loop
+        without first creating a window. You should thus not create another
+        window but use instead the created one. See 'gui-glut.py' in the
+        docs/examples/lib directory.
+        
+        The default screen mode is set to:
 
-        GLUT is quite an old library and it is difficult to ensure proper
-        integration within IPython since original GLUT does not allow to handle
-        events one by one. Instead, it requires for the mainloop to be entered
-        and never returned (there is not even a function to exit he
-        mainloop). Fortunately, there are alternatives such as freeglut
-        (available for linux and windows) and the OSX implementation gives
-        access to a glutCheckLoop() function that blocks itself until a new
-        event is received. This means we have to setup a default timer to
-        ensure we got at least one event that will unblock the function. We set
-        a default timer of 60fps.
-
-        Furthermore, it is not possible to install these handlers without a
-        window being first created. We choose to make this window invisible and
-        the user is supposed to make it visible when needed (see gui-glut.py in
-        the docs/examples/lib directory). This means that display mode options
-        are set at this level and user won't be able to change them later
-        without modifying the code. This should probably be made available via
-        IPython options system.
+          glut.GLUT_DOUBLE | glut.GLUT_RGBA | glut.GLUT_DEPTH
 
         Script integration
         ------------------
 
           if glut.glutGetWindow() > 0:
               interactive = True
               glut.glutShowWindow()
           else:
               interactive = False
               glut.glutInit(sys.argv)
               glut.glutInitDisplayMode( glut.GLUT_DOUBLE |
                                         glut.GLUT_RGBA   |
                                         glut.GLUT_DEPTH )
           ...
           if not interactive:
               glut.glutMainLoop()
         """
+        # GLUT is quite an old library and it is difficult to ensure proper
+        # integration within IPython since original GLUT does not allow to handle
+        # events one by one. Instead, it requires for the mainloop to be entered
+        # and never returned (there is not even a function to exit he
+        # mainloop). Fortunately, there are alternatives such as freeglut
+        # (available for linux and windows) and the OSX implementation gives
+        # access to a glutCheckLoop() function that blocks itself until a new
+        # event is received. This means we have to setup a default timer to
+        # ensure we got at least one event that will unblock the function. We set
+        # a default timer of 60fps.
+        #
+        # Furthermore, it is not possible to install these handlers without a
+        # window being first created. We choose to make this window invisible and
+        # the user is supposed to make it visible when needed (see gui-glut.py in
+        # the docs/examples/lib directory). This means that display mode options
+        # are set at this level and user won't be able to change them later
+        # without modifying the code. This should probably be made available via
+        # IPython options system.
+
+        import OpenGL
+        OpenGL.ERROR_CHECKING = False
         import OpenGL.GLUT as glut
         import OpenGL.platform as platform
+        import time
 
-        def timer_none(fps):
-            ''' Dummy timer function '''
-            pass
+
+        # Frame per second : 60
+        # Should probably be an IPython option
+        glut_fps = 60
+        
+
+        # Display mode : double buffeed + rgba + depth
+        # Should probably be an IPython option
+        glut_display_mode = (glut.GLUT_DOUBLE |
+                             glut.GLUT_RGBA   |
+                             glut.GLUT_DEPTH)
+
+        glut_interrupted = False
 
         def display():
             ''' Dummy display function '''
             pass
 
         def timer(fps):
             # We should normally set the active window to 1 and post a
             # redisplay for each window.  The problem is that we do not know
             # how much active windows we have and there is no function in glut
             # to get that number.
             # glut.glutSetWindow(1)
             glut.glutTimerFunc( int(1000.0/fps), timer, fps)
             glut.glutPostRedisplay()
 
+        def close():
+            glut.glutHideWindow()
+
         glutMainLoopEvent = None
         if sys.platform == 'darwin':
             try:
-                glutCheckLoop = platform.createBaseFunction(
-                    'glutCheckLoop', dll=platform.GLUT, resultType=None,
+                glutCheckLoop = platform.createBaseFunction( 
+                    'glutCheckLoop', dll=platform.GLUT, resultType=None, 
                     argTypes=[],
-                    doc='glutCheckLoop(  ) -> None',
+                    doc='glutCheckLoop(  ) -> None', 
                     argNames=(),
                     )
             except AttributeError:
                 raise RuntimeError(
                     '''Your glut implementation does not allow interactive sessions'''
                     '''Consider installing freeglut.''')
             glutMainLoopEvent = glutCheckLoop
         elif glut.HAVE_FREEGLUT:
             glutMainLoopEvent = glut.glutMainLoopEvent
         else:
             raise RuntimeError(
                 '''Your glut implementation does not allow interactive sessions. '''
                 '''Consider installing freeglut.''')
 
         def inputhook_glut():
-            """ Process pending GLUT events only. """
-            # We need to protect against a user pressing Control-C when IPython is
-            # idle and this is running. We trap KeyboardInterrupt and pass.
+            """ Process pending GLUT events only. """            
+
+            # We need to protect against a user pressing Control-C when IPython
+            # is idle and this is running. We should trap KeyboardInterrupt and
+            # pass but it does not seem to work with glutMainLoopEvent.
+            # Instead, we setup a signal handler on SIGINT and returns after
+            # having restored the default python SIGINT handler.
+            import signal
+            def handler(signum, frame):
+                signal.signal(signal.SIGINT, signal.default_int_handler)
+                print '\nKeyboardInterrupt'
+                # Need to reprint the prompt at this stage
+
+            signal.signal(signal.SIGINT, handler)
+
             try:
                 glutMainLoopEvent()
-            except KeyboardInterrupt:
+            except KeyboardInterrupt: # this catch doesn't work for some reasons...
                 pass
-            return 0
 
-        # Frame per second : 60
-        # Should be probably an IPython option
-        fps = 60
+            return 0
+            
         if not self._apps.has_key(GUI_GLUT):
             glut.glutInit(sys.argv)
-
-            # Display mode shoudl be also an Ipython option since user won't be able
+            # Display mode should be also an Ipython option since user won't be able
             # to change it later
-            glut.glutInitDisplayMode(glut.GLUT_DOUBLE | glut.GLUT_RGBA | glut.GLUT_DEPTH)
+            glut.glutInitDisplayMode(glut_display_mode)
             glut.glutCreateWindow(sys.argv[0])
-            # glut.glutReshapeWindow(1,1)
             glut.glutHideWindow()
+            glut.glutWMCloseFunc(close)
             glut.glutDisplayFunc(display)
-            glut.glutTimerFunc( int(1000.0/fps), timer, fps)
+            glut.glutTimerFunc( int(1000.0/glut_fps), timer, glut_fps)
         else:
+            glut.glutWMCloseFunc(close)
             glut.glutDisplayFunc(display)
-            glut.glutTimerFunc( int(1000.0/fps), timer, fps)
+            glut.glutTimerFunc( int(1000.0/glut_fps), timer, glut_fps)
 
         self.set_inputhook(inputhook_glut)
         self._current_gui = GUI_GLUT
         self._apps[GUI_GLUT] = True
 
-
     def disable_glut(self):
         """Disable event loop integration with glut.
-
+        
         This sets PyOS_InputHook to NULL and set the display function to a
         dummy one and set the timer to a dummy timer that will be triggered
         very far in the future.
         """
-        glut.HideWindow()
-        glut.glutTimerFunc( sys.maxint-1, null_timer_none, 0)
->>>>>>> Added code for the GLUT interactive session
+        import signal
+        import OpenGL
+        OpenGL.ERROR_CHECKING = False
+        import OpenGL.GLUT as glut
+        import OpenGL.platform as platform
+
+        def timer_none(fps):
+            ''' Dummy timer function '''
+            pass
+
+        glutMainLoopEvent = None
+        if sys.platform == 'darwin':
+            try:
+                glutCheckLoop = platform.createBaseFunction( 
+                    'glutCheckLoop', dll=platform.GLUT, resultType=None, 
+                    argTypes=[],
+                    doc='glutCheckLoop(  ) -> None', 
+                    argNames=(),
+                    )
+            except AttributeError:
+                raise RuntimeError(
+                    '''Your glut implementation does not allow interactive sessions'''
+                    '''Consider installing freeglut.''')
+            glutMainLoopEvent = glutCheckLoop
+        elif glut.HAVE_FREEGLUT:
+            glutMainLoopEvent = glut.glutMainLoopEvent
+        else:
+            raise RuntimeError(
+                '''Your glut implementation does not allow interactive sessions. '''
+                '''Consider installing freeglut.''')
+
+        glut.glutHideWindow() # This is an event to be processed below
+        glutMainLoopEvent()
+        #glut.glutTimerFunc( sys.maxint-1, timer_none, 0)
         self.clear_inputhook()
+        #signal.signal(signal.SIGINT, signal.default_int_handler)
+
+    def enable_pyglet(self, app=None):
+        """Enable event loop integration with pyglet.
+
+        Parameters
+        ----------
+        app : ignored
+           Ignored, it's only a placeholder to keep the call signature of all
+           gui activation methods consistent, which simplifies the logic of
+           supporting magics.
 
+        Notes
+        -----
+        This methods sets the ``PyOS_InputHook`` for pyglet, which allows
+        pyglet to integrate with terminal based applications like
+        IPython.
+
+        """
+        import pyglet
+        from IPython.lib.inputhookpyglet import inputhook_pyglet
+        self.set_inputhook(inputhook_pyglet)
+        self._current_gui = GUI_PYGLET
+        return app
+
+    def disable_pyglet(self):
+        """Disable event loop integration with pyglet.
+
+        This merely sets PyOS_InputHook to NULL.
+        """
+        self.clear_inputhook()
 
     def current_gui(self):
         """Return a string indicating the currently active GUI or None."""
         return self._current_gui
 
 inputhook_manager = InputHookManager()
 
 enable_wx = inputhook_manager.enable_wx
 disable_wx = inputhook_manager.disable_wx
 enable_qt4 = inputhook_manager.enable_qt4
 disable_qt4 = inputhook_manager.disable_qt4
 enable_gtk = inputhook_manager.enable_gtk
 disable_gtk = inputhook_manager.disable_gtk
 enable_tk = inputhook_manager.enable_tk
 disable_tk = inputhook_manager.disable_tk
-<<<<<<< HEAD
-enable_pyglet = inputhook_manager.enable_pyglet
-disable_pyglet = inputhook_manager.disable_pyglet
-=======
 enable_glut = inputhook_manager.enable_glut
 disable_glut = inputhook_manager.disable_glut
->>>>>>> Added code for the GLUT interactive session
+enable_pyglet = inputhook_manager.enable_pyglet
+disable_pyglet = inputhook_manager.disable_pyglet
 clear_inputhook = inputhook_manager.clear_inputhook
 set_inputhook = inputhook_manager.set_inputhook
 current_gui = inputhook_manager.current_gui
 clear_app_refs = inputhook_manager.clear_app_refs
 
 
 # Convenience function to switch amongst them
 def enable_gui(gui=None, app=None):
     """Switch amongst GUI input hooks by name.
 
     This is just a utility wrapper around the methods of the InputHookManager
     object.
 
     Parameters
     ----------
     gui : optional, string or None
       If None, clears input hook, otherwise it must be one of the recognized
       GUI names (see ``GUI_*`` constants in module).
 
     app : optional, existing application object.
       For toolkits that have the concept of a global app, you can supply an
       existing one.  If not given, the toolkit will be probed for one, and if
       none is found, a new one will be created.  Note that GTK does not have
       this concept, and passing an app if `gui`=="GTK" will raise an error.
 
     Returns
     -------
     The output of the underlying gui switch routine, typically the actual
     PyOS_InputHook wrapper object or the GUI toolkit app created, if there was
     one.
     """
     guis = {None: clear_inputhook,
             GUI_OSX: lambda app=False: None,
             GUI_TK: enable_tk,
             GUI_GTK: enable_gtk,
             GUI_WX: enable_wx,
             GUI_QT: enable_qt4, # qt3 not supported
             GUI_QT4: enable_qt4,
-<<<<<<< HEAD
+            GUI_GLUT: enable_glut,
             GUI_PYGLET: enable_pyglet,
             }
-=======
-            GUI_GLUT: enable_glut}
->>>>>>> Added code for the GLUT interactive session
     try:
         gui_hook = guis[gui]
     except KeyError:
         e = "Invalid GUI request %r, valid ones are:%s" % (gui, guis.keys())
         raise ValueError(e)
     return gui_hook(app)