Add OS X input hook

It almost works: not responsive due to input callback not waking app until window is interacted with

IPython/terminal/pt_inputhooks/osx.py

@@ -0,0 +1,104 b''
+
+# obj-c boilerplate from appnope, used under BSD 2-clause
+
+import ctypes
+import ctypes.util
+
+objc = ctypes.cdll.LoadLibrary(ctypes.util.find_library('objc'))
+CoreFoundation = ctypes.cdll.LoadLibrary(ctypes.util.find_library('CoreFoundation'))
+# Cocoa = ctypes.cdll.LoadLibrary(ctypes.util.find_library('Cocoa'))
+
+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 methods)"""
+    return objc.sel_registerName(_utf8(name))
+
+def C(classname):
+    """get an ObjC Class by name"""
+    return objc.objc_getClass(_utf8(classname))
+
+# CoreFoundation calls we will use:
+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 _input_callback(fdref, flags, info):
+    """Callback to fire when there's input to be read"""
+    CFFileDescriptorInvalidate(fdref)
+    CFRelease(fdref)
+    NSApp = _NSApp()
+    msg(NSApp, n('stop:'), NSApp)
+
+_c_callback_func_type = ctypes.CFUNCTYPE(None, void_p, void_p, void_p)
+_c_callback = _c_callback_func_type(_input_callback)
+
+def _stop_on_read(fd):
+    """Register callback to stop eventloop when there's data on fd"""
+    fdref = CFFileDescriptorCreate(None, fd, False, _c_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()
+    window_count = msg(
+        msg(NSApp, n('windows')),
+        n('count')
+    )
+    if not window_count:
+        return
+    _stop_on_read(context.fileno())
+    msg(NSApp, n('run'))

IPython/terminal/pt_inputhooks/__init__.py

@@ -12,6 +12,7 b' backends = ['
     'tk',
     'wx',
     'pyglet', 'glut',
+    'osx',
 ]
 
 class UnknownBackend(KeyError):