inputhooks

packages/python/yap_kernel/yap_ipython/terminal/pt_inputhooks/__init__.py

@@ -0,0 +1,49 @@
+import importlib
+import os
+
+aliases = {
+    'qt4': 'qt',
+    'gtk2': 'gtk',
+}
+
+backends = [
+    'qt', 'qt4', 'qt5',
+    'gtk', 'gtk2', 'gtk3',
+    'tk',
+    'wx',
+    'pyglet', 'glut',
+    'osx',
+]
+
+registered = {}
+
+def register(name, inputhook):
+    """Register the function *inputhook* as an event loop integration."""
+    registered[name] = inputhook
+
+class UnknownBackend(KeyError):
+    def __init__(self, name):
+        self.name = name
+
+    def __str__(self):
+        return ("No event loop integration for {!r}. "
+                "Supported event loops are: {}").format(self.name,
+                                    ', '.join(backends + sorted(registered)))
+
+def get_inputhook_name_and_func(gui):
+    if gui in registered:
+        return gui, registered[gui]
+
+    if gui not in backends:
+        raise UnknownBackend(gui)
+
+    if gui in aliases:
+        return get_inputhook_name_and_func(aliases[gui])
+
+    gui_mod = gui
+    if gui == 'qt5':
+        os.environ['QT_API'] = 'pyqt5'
+        gui_mod = 'qt'
+
+    mod = importlib.import_module('yap_ipython.terminal.pt_inputhooks.'+gui_mod)
+    return gui, mod.inputhook

packages/python/yap_kernel/yap_ipython/terminal/pt_inputhooks/glut.py

@@ -0,0 +1,140 @@
+"""GLUT Input hook for interactive use with prompt_toolkit
+"""
+
+
+# GLUT is quite an old library and it is difficult to ensure proper
+# integration within yap_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 the idle callback to
+# ensure we got at least one event that will unblock the function.
+#
+# Furthermore, it is not possible to install these handlers without a window
+# being first created. We choose to make this window invisible. 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 yap_ipython options system.
+
+import sys
+import time
+import signal
+import OpenGL.GLUT as glut
+import OpenGL.platform as platform
+from timeit import default_timer as clock
+
+# Frame per second : 60
+# Should probably be an yap_ipython option
+glut_fps = 60
+
+# Display mode : double buffeed + rgba + depth
+# Should probably be an yap_ipython option
+glut_display_mode = (glut.GLUT_DOUBLE |
+                     glut.GLUT_RGBA   |
+                     glut.GLUT_DEPTH)
+
+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.''')
+
+
+def glut_display():
+    # Dummy display function
+    pass
+
+def glut_idle():
+    # Dummy idle function
+    pass
+
+def glut_close():
+    # Close function only hides the current window
+    glut.glutHideWindow()
+    glutMainLoopEvent()
+
+def glut_int_handler(signum, frame):
+    # Catch sigint and print the defaultipyt   message
+    signal.signal(signal.SIGINT, signal.default_int_handler)
+    print('\nKeyboardInterrupt')
+    # Need to reprint the prompt at this stage
+
+# Initialisation code
+glut.glutInit( sys.argv )
+glut.glutInitDisplayMode( glut_display_mode )
+# This is specific to freeglut
+if bool(glut.glutSetOption):
+    glut.glutSetOption( glut.GLUT_ACTION_ON_WINDOW_CLOSE,
+                        glut.GLUT_ACTION_GLUTMAINLOOP_RETURNS )
+glut.glutCreateWindow( b'ipython' )
+glut.glutReshapeWindow( 1, 1 )
+glut.glutHideWindow( )
+glut.glutWMCloseFunc( glut_close )
+glut.glutDisplayFunc( glut_display )
+glut.glutIdleFunc( glut_idle )
+
+
+def inputhook(context):
+    """Run the pyglet event loop by processing pending events only.
+
+    This keeps processing pending events until stdin is ready.  After
+    processing all pending events, a call to time.sleep is inserted.  This is
+    needed, otherwise, CPU usage is at 100%.  This sleep time should be tuned
+    though for best performance.
+    """
+    # We need to protect against a user pressing Control-C when yap_ipython is
+    # idle and this is running. We trap KeyboardInterrupt and pass.
+
+    signal.signal(signal.SIGINT, glut_int_handler)
+
+    try:
+        t = clock()
+
+        # Make sure the default window is set after a window has been closed
+        if glut.glutGetWindow() == 0:
+            glut.glutSetWindow( 1 )
+            glutMainLoopEvent()
+            return 0
+
+        while not context.input_is_ready():
+            glutMainLoopEvent()
+            # We need to sleep at this point to keep the idle CPU load
+            # low.  However, if sleep to long, GUI response is poor.  As
+            # a compromise, we watch how often GUI events are being processed
+            # and switch between a short and long sleep time.  Here are some
+            # stats useful in helping to tune this.
+            # time    CPU load
+            # 0.001   13%
+            # 0.005   3%
+            # 0.01    1.5%
+            # 0.05    0.5%
+            used_time = clock() - t
+            if used_time > 10.0:
+                # print 'Sleep for 1 s'  # dbg
+                time.sleep(1.0)
+            elif used_time > 0.1:
+                # Few GUI events coming in, so we can sleep longer
+                # print 'Sleep for 0.05 s'  # dbg
+                time.sleep(0.05)
+            else:
+                # Many GUI events coming in, so sleep only very little
+                time.sleep(0.001)
+    except KeyboardInterrupt:
+        pass

packages/python/yap_kernel/yap_ipython/terminal/pt_inputhooks/gtk.py

@@ -0,0 +1,58 @@
+# Code borrowed from python-prompt-toolkit examples
+# https://github.com/jonathanslenders/python-prompt-toolkit/blob/77cdcfbc7f4b4c34a9d2f9a34d422d7152f16209/examples/inputhook.py
+
+# Copyright (c) 2014, Jonathan Slenders
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without modification,
+# are permitted provided that the following conditions are met:
+#
+# * Redistributions of source code must retain the above copyright notice, this
+#   list of conditions and the following disclaimer.
+#
+# * 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.
+#
+# * Neither the name of the {organization} nor the names of its
+#   contributors may be used to endorse or promote products derived from
+#   this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER OR CONTRIBUTORS 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.
+
+"""
+PyGTK input hook for prompt_toolkit.
+
+Listens on the pipe prompt_toolkit sets up for a notification that it should
+return control to the terminal event loop.
+"""
+
+import gtk, gobject
+
+# Enable threading in GTK. (Otherwise, GTK will keep the GIL.)
+gtk.gdk.threads_init()
+
+def inputhook(context):
+    """
+    When the eventloop of prompt-toolkit is idle, call this inputhook.
+
+    This will run the GTK main loop until the file descriptor
+    `context.fileno()` becomes ready.
+
+    :param context: An `InputHookContext` instance.
+    """
+    def _main_quit(*a, **kw):
+        gtk.main_quit()
+        return False
+
+    gobject.io_add_watch(context.fileno(), gobject.IO_IN, _main_quit)
+    gtk.main()

packages/python/yap_kernel/yap_ipython/terminal/pt_inputhooks/gtk3.py

@@ -0,0 +1,12 @@
+"""prompt_toolkit input hook for GTK 3
+"""
+
+from gi.repository import Gtk, GLib
+
+def _main_quit(*args, **kwargs):
+    Gtk.main_quit()
+    return False
+
+def inputhook(context):
+    GLib.io_add_watch(context.fileno(), GLib.PRIORITY_DEFAULT, GLib.IO_IN, _main_quit)
+    Gtk.main()

packages/python/yap_kernel/yap_ipython/terminal/pt_inputhooks/osx.py

@@ -0,0 +1,137 @@
+"""Inputhook for OS X
+
+Calls NSApp / CoreFoundation APIs via ctypes.
+"""
+
+# obj-c boilerplate from appnope, used under BSD 2-clause
+
+import ctypes
+import ctypes.util
+from threading import Event
+
+objc = ctypes.cdll.LoadLibrary(ctypes.util.find_library('objc'))
+
+void_p = ctypes.c_void_p
+
+objc.objc_getClass.restype = void_p
+objc.sel_registerName.restype = void_p
+objc.objc_msgSend.restype = void_p
+objc.objc_msgSend.argtypes = [void_p, void_p]
+
+msg = objc.objc_msgSend
+
+def _utf8(s):
+    """ensure utf8 bytes"""
+    if not isinstance(s, bytes):
+        s = s.encode('utf8')
+    return s
+
+def n(name):
+    """create a selector name (for ObjC methods)"""
+    return objc.sel_registerName(_utf8(name))
+
+def C(classname):
+    """get an ObjC Class by name"""
+    return objc.objc_getClass(_utf8(classname))
+
+# end obj-c boilerplate from appnope
+
+# CoreFoundation C-API calls we will use:
+CoreFoundation = ctypes.cdll.LoadLibrary(ctypes.util.find_library('CoreFoundation'))
+
+CFFileDescriptorCreate = CoreFoundation.CFFileDescriptorCreate
+CFFileDescriptorCreate.restype = void_p
+CFFileDescriptorCreate.argtypes = [void_p, ctypes.c_int, ctypes.c_bool, void_p]
+
+CFFileDescriptorGetNativeDescriptor = CoreFoundation.CFFileDescriptorGetNativeDescriptor
+CFFileDescriptorGetNativeDescriptor.restype = ctypes.c_int
+CFFileDescriptorGetNativeDescriptor.argtypes = [void_p]
+
+CFFileDescriptorEnableCallBacks = CoreFoundation.CFFileDescriptorEnableCallBacks
+CFFileDescriptorEnableCallBacks.restype = None
+CFFileDescriptorEnableCallBacks.argtypes = [void_p, ctypes.c_ulong]
+
+CFFileDescriptorCreateRunLoopSource = CoreFoundation.CFFileDescriptorCreateRunLoopSource
+CFFileDescriptorCreateRunLoopSource.restype = void_p
+CFFileDescriptorCreateRunLoopSource.argtypes = [void_p, void_p, void_p]
+
+CFRunLoopGetCurrent = CoreFoundation.CFRunLoopGetCurrent
+CFRunLoopGetCurrent.restype = void_p
+
+CFRunLoopAddSource = CoreFoundation.CFRunLoopAddSource
+CFRunLoopAddSource.restype = None
+CFRunLoopAddSource.argtypes = [void_p, void_p, void_p]
+
+CFRelease = CoreFoundation.CFRelease
+CFRelease.restype = None
+CFRelease.argtypes = [void_p]
+
+CFFileDescriptorInvalidate = CoreFoundation.CFFileDescriptorInvalidate
+CFFileDescriptorInvalidate.restype = None
+CFFileDescriptorInvalidate.argtypes = [void_p]
+
+# From CFFileDescriptor.h
+kCFFileDescriptorReadCallBack = 1
+kCFRunLoopCommonModes = void_p.in_dll(CoreFoundation, 'kCFRunLoopCommonModes')
+
+
+def _NSApp():
+    """Return the global NSApplication instance (NSApp)"""
+    return msg(C('NSApplication'), n('sharedApplication'))
+
+
+def _wake(NSApp):
+    """Wake the Application"""
+    event = msg(C('NSEvent'),
+        n('otherEventWithType:location:modifierFlags:'
+          'timestamp:windowNumber:context:subtype:data1:data2:'),
+        15, # Type
+        0, # location
+        0, # flags
+        0, # timestamp
+        0, # window
+        None, # context
+        0, # subtype
+        0, # data1
+        0, # data2
+    )
+    msg(NSApp, n('postEvent:atStart:'), void_p(event), True)
+
+
+_triggered = Event()
+
+def _input_callback(fdref, flags, info):
+    """Callback to fire when there's input to be read"""
+    _triggered.set()
+    CFFileDescriptorInvalidate(fdref)
+    CFRelease(fdref)
+    NSApp = _NSApp()
+    msg(NSApp, n('stop:'), NSApp)
+    _wake(NSApp)
+
+_c_callback_func_type = ctypes.CFUNCTYPE(None, void_p, void_p, void_p)
+_c_input_callback = _c_callback_func_type(_input_callback)
+
+
+def _stop_on_read(fd):
+    """Register callback to stop eventloop when there's data on fd"""
+    _triggered.clear()
+    fdref = CFFileDescriptorCreate(None, fd, False, _c_input_callback, None)
+    CFFileDescriptorEnableCallBacks(fdref, kCFFileDescriptorReadCallBack)
+    source = CFFileDescriptorCreateRunLoopSource(None, fdref, 0)
+    loop = CFRunLoopGetCurrent()
+    CFRunLoopAddSource(loop, source, kCFRunLoopCommonModes)
+    CFRelease(source)
+
+
+def inputhook(context):
+    """Inputhook for Cocoa (NSApp)"""
+    NSApp = _NSApp()
+    _stop_on_read(context.fileno())
+    msg(NSApp, n('run'))
+    if not _triggered.is_set():
+        # app closed without firing callback,
+        # probably due to last window being closed.
+        # Run the loop manually in this case,
+        # since there may be events still to process (#9734)
+        CoreFoundation.CFRunLoopRun()

packages/python/yap_kernel/yap_ipython/terminal/pt_inputhooks/pyglet.py

@@ -0,0 +1,66 @@
+"""Enable pyglet to be used interacively with prompt_toolkit
+"""
+
+import sys
+import time
+from timeit import default_timer as clock
+import pyglet
+
+# On linux only, window.flip() has a bug that causes an AttributeError on
+# window close.  For details, see:
+# http://groups.google.com/group/pyglet-users/browse_thread/thread/47c1aab9aa4a3d23/c22f9e819826799e?#c22f9e819826799e
+
+if sys.platform.startswith('linux'):
+    def flip(window):
+        try:
+            window.flip()
+        except AttributeError:
+            pass
+else:
+    def flip(window):
+        window.flip()
+
+
+def inputhook(context):
+    """Run the pyglet event loop by processing pending events only.
+
+    This keeps processing pending events until stdin is ready.  After
+    processing all pending events, a call to time.sleep is inserted.  This is
+    needed, otherwise, CPU usage is at 100%.  This sleep time should be tuned
+    though for best performance.
+    """
+    # We need to protect against a user pressing Control-C when yap_ipython is
+    # idle and this is running. We trap KeyboardInterrupt and pass.
+    try:
+        t = clock()
+        while not context.input_is_ready():
+            pyglet.clock.tick()
+            for window in pyglet.app.windows:
+                window.switch_to()
+                window.dispatch_events()
+                window.dispatch_event('on_draw')
+                flip(window)
+
+            # We need to sleep at this point to keep the idle CPU load
+            # low.  However, if sleep to long, GUI response is poor.  As
+            # a compromise, we watch how often GUI events are being processed
+            # and switch between a short and long sleep time.  Here are some
+            # stats useful in helping to tune this.
+            # time    CPU load
+            # 0.001   13%
+            # 0.005   3%
+            # 0.01    1.5%
+            # 0.05    0.5%
+            used_time = clock() - t
+            if used_time > 10.0:
+                # print 'Sleep for 1 s'  # dbg
+                time.sleep(1.0)
+            elif used_time > 0.1:
+                # Few GUI events coming in, so we can sleep longer
+                # print 'Sleep for 0.05 s'  # dbg
+                time.sleep(0.05)
+            else:
+                # Many GUI events coming in, so sleep only very little
+                time.sleep(0.001)
+    except KeyboardInterrupt:
+        pass

packages/python/yap_kernel/yap_ipython/terminal/pt_inputhooks/qt.py

@@ -0,0 +1,35 @@
+import sys
+from yap_ipython.external.qt_for_kernel import QtCore, QtGui
+
+# If we create a QApplication, keep a reference to it so that it doesn't get
+# garbage collected.
+_appref = None
+
+
+def inputhook(context):
+    global _appref
+    app = QtCore.QCoreApplication.instance()
+    if not app:
+        _appref = app = QtGui.QApplication([" "])
+    event_loop = QtCore.QEventLoop(app)
+
+    if sys.platform == 'win32':
+        # The QSocketNotifier method doesn't appear to work on Windows.
+        # Use polling instead.
+        timer = QtCore.QTimer()
+        timer.timeout.connect(event_loop.quit)
+        while not context.input_is_ready():
+            timer.start(50)  # 50 ms
+            event_loop.exec_()
+            timer.stop()
+    else:
+        # On POSIX platforms, we can use a file descriptor to quit the event
+        # loop when there is input ready to read.
+        notifier = QtCore.QSocketNotifier(context.fileno(),
+                                          QtCore.QSocketNotifier.Read)
+        # connect the callback we care about before we turn it on
+        notifier.activated.connect(event_loop.exit)
+        notifier.setEnabled(True)
+        # only start the event loop we are not already flipped
+        if not context.input_is_ready():
+            event_loop.exec_()

packages/python/yap_kernel/yap_ipython/terminal/pt_inputhooks/tk.py

@@ -0,0 +1,90 @@
+# Code borrowed from ptpython
+# https://github.com/jonathanslenders/ptpython/blob/86b71a89626114b18898a0af463978bdb32eeb70/ptpython/eventloop.py
+
+# Copyright (c) 2015, Jonathan Slenders
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without modification,
+# are permitted provided that the following conditions are met:
+#
+# * Redistributions of source code must retain the above copyright notice, this
+#   list of conditions and the following disclaimer.
+#
+# * 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.
+#
+# * Neither the name of the {organization} nor the names of its
+#   contributors may be used to endorse or promote products derived from
+#   this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER OR CONTRIBUTORS 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.
+
+"""
+Wrapper around the eventloop that gives some time to the Tkinter GUI to process
+events when it's loaded and while we are waiting for input at the REPL. This
+way we don't block the UI of for instance ``turtle`` and other Tk libraries.
+
+(Normally Tkinter registers it's callbacks in ``PyOS_InputHook`` to integrate
+in readline. ``prompt-toolkit`` doesn't understand that input hook, but this
+will fix it for Tk.)
+"""
+import time
+
+import _tkinter
+import tkinter
+
+def inputhook(inputhook_context):
+    """
+    Inputhook for Tk.
+    Run the Tk eventloop until prompt-toolkit needs to process the next input.
+    """
+    # Get the current TK application.
+    root = tkinter._default_root
+
+    def wait_using_filehandler():
+        """
+        Run the TK eventloop until the file handler that we got from the
+        inputhook becomes readable.
+        """
+        # Add a handler that sets the stop flag when `prompt-toolkit` has input
+        # to process.
+        stop = [False]
+        def done(*a):
+            stop[0] = True
+
+        root.createfilehandler(inputhook_context.fileno(), _tkinter.READABLE, done)
+
+        # Run the TK event loop as long as we don't receive input.
+        while root.dooneevent(_tkinter.ALL_EVENTS):
+            if stop[0]:
+                break
+
+        root.deletefilehandler(inputhook_context.fileno())
+
+    def wait_using_polling():
+        """
+        Windows TK doesn't support 'createfilehandler'.
+        So, run the TK eventloop and poll until input is ready.
+        """
+        while not inputhook_context.input_is_ready():
+            while root.dooneevent(_tkinter.ALL_EVENTS | _tkinter.DONT_WAIT):
+                 pass
+            # Sleep to make the CPU idle, but not too long, so that the UI
+            # stays responsive.
+            time.sleep(.01)
+
+    if root is not None:
+        if hasattr(root, 'createfilehandler'):
+            wait_using_filehandler()
+        else:
+            wait_using_polling()

packages/python/yap_kernel/yap_ipython/terminal/pt_inputhooks/wx.py

@@ -0,0 +1,147 @@
+"""Enable wxPython to be used interacively in prompt_toolkit
+"""
+
+import sys
+import signal
+import time
+from timeit import default_timer as clock
+import wx
+
+
+def inputhook_wx1(context):
+    """Run the wx event loop by processing pending events only.
+
+    This approach seems to work, but its performance is not great as it
+    relies on having PyOS_InputHook called regularly.
+    """
+    try:
+        app = wx.GetApp()
+        if app is not None:
+            assert wx.Thread_IsMain()
+
+            # Make a temporary event loop and process system events until
+            # there are no more waiting, then allow idle events (which
+            # will also deal with pending or posted wx events.)
+            evtloop = wx.EventLoop()
+            ea = wx.EventLoopActivator(evtloop)
+            while evtloop.Pending():
+                evtloop.Dispatch()
+            app.ProcessIdle()
+            del ea
+    except KeyboardInterrupt:
+        pass
+    return 0
+
+class EventLoopTimer(wx.Timer):
+
+    def __init__(self, func):
+        self.func = func
+        wx.Timer.__init__(self)
+
+    def Notify(self):
+        self.func()
+
+class EventLoopRunner(object):
+
+    def Run(self, time, input_is_ready):
+        self.input_is_ready = input_is_ready
+        self.evtloop = wx.EventLoop()
+        self.timer = EventLoopTimer(self.check_stdin)
+        self.timer.Start(time)
+        self.evtloop.Run()
+
+    def check_stdin(self):
+        if self.input_is_ready():
+            self.timer.Stop()
+            self.evtloop.Exit()
+
+def inputhook_wx2(context):
+    """Run the wx event loop, polling for stdin.
+
+    This version runs the wx eventloop for an undetermined amount of time,
+    during which it periodically checks to see if anything is ready on
+    stdin.  If anything is ready on stdin, the event loop exits.
+
+    The argument to elr.Run controls how often the event loop looks at stdin.
+    This determines the responsiveness at the keyboard.  A setting of 1000
+    enables a user to type at most 1 char per second.  I have found that a
+    setting of 10 gives good keyboard response.  We can shorten it further,
+    but eventually performance would suffer from calling select/kbhit too
+    often.
+    """
+    try:
+        app = wx.GetApp()
+        if app is not None:
+            assert wx.Thread_IsMain()
+            elr = EventLoopRunner()
+            # As this time is made shorter, keyboard response improves, but idle
+            # CPU load goes up.  10 ms seems like a good compromise.
+            elr.Run(time=10,  # CHANGE time here to control polling interval
+                    input_is_ready=context.input_is_ready)
+    except KeyboardInterrupt:
+        pass
+    return 0
+
+def inputhook_wx3(context):
+    """Run the wx event loop by processing pending events only.
+
+    This is like inputhook_wx1, but it keeps processing pending events
+    until stdin is ready.  After processing all pending events, a call to
+    time.sleep is inserted.  This is needed, otherwise, CPU usage is at 100%.
+    This sleep time should be tuned though for best performance.
+    """
+    # We need to protect against a user pressing Control-C when yap_ipython is
+    # idle and this is running. We trap KeyboardInterrupt and pass.
+    try:
+        app = wx.GetApp()
+        if app is not None:
+            assert wx.Thread_IsMain()
+
+            # The import of wx on Linux sets the handler for signal.SIGINT
+            # to 0.  This is a bug in wx or gtk.  We fix by just setting it
+            # back to the Python default.
+            if not callable(signal.getsignal(signal.SIGINT)):
+                signal.signal(signal.SIGINT, signal.default_int_handler)
+
+            evtloop = wx.EventLoop()
+            ea = wx.EventLoopActivator(evtloop)
+            t = clock()
+            while not context.input_is_ready():
+                while evtloop.Pending():
+                    t = clock()
+                    evtloop.Dispatch()
+                app.ProcessIdle()
+                # We need to sleep at this point to keep the idle CPU load
+                # low.  However, if sleep to long, GUI response is poor.  As
+                # a compromise, we watch how often GUI events are being processed
+                # and switch between a short and long sleep time.  Here are some
+                # stats useful in helping to tune this.
+                # time    CPU load
+                # 0.001   13%
+                # 0.005   3%
+                # 0.01    1.5%
+                # 0.05    0.5%
+                used_time = clock() - t
+                if used_time > 10.0:
+                    # print 'Sleep for 1 s'  # dbg
+                    time.sleep(1.0)
+                elif used_time > 0.1:
+                    # Few GUI events coming in, so we can sleep longer
+                    # print 'Sleep for 0.05 s'  # dbg
+                    time.sleep(0.05)
+                else:
+                    # Many GUI events coming in, so sleep only very little
+                    time.sleep(0.001)
+            del ea
+    except KeyboardInterrupt:
+        pass
+    return 0
+
+if sys.platform == 'darwin':
+    # On OSX, evtloop.Pending() always returns True, regardless of there being
+    # any events pending. As such we can't use implementations 1 or 3 of the
+    # inputhook as those depend on a pending/dispatch loop.
+    inputhook = inputhook_wx2
+else:
+    # This is our default implementation
+    inputhook = inputhook_wx3