cpython/Lib/plat-mac/argvemulator.py

"""argvemulator - create sys.argv from OSA events. Used by applets that
want unix-style arguments.
"""

import sys
import traceback
from Carbon import AE
from Carbon.AppleEvents import *
from Carbon import Evt
from Carbon.Events import *
import aetools

class ArgvCollector:

        """A minimal FrameWork.Application-like class"""

        def __init__(self):
                self.quitting = 0
                self.ae_handlers = {}
                # Remove the funny -psn_xxx_xxx argument
                if len(sys.argv) > 1 and sys.argv[1][:4] == '-psn':
                        del sys.argv[1]
                self.installaehandler('aevt', 'oapp', self.open_app)
                self.installaehandler('aevt', 'odoc', self.open_file)

        def installaehandler(self, classe, type, callback):
                AE.AEInstallEventHandler(classe, type, self.callback_wrapper)
                self.ae_handlers[(classe, type)] = callback

        def close(self):
                for classe, type in self.ae_handlers.keys():
                        AE.AERemoveEventHandler(classe, type)

        def mainloop(self, mask = highLevelEventMask, timeout = 1*60):
                stoptime = Evt.TickCount() + timeout
                while not self.quitting and Evt.TickCount() < stoptime:
                        self.dooneevent(mask, timeout)
                self.close()

        def _quit(self):
                self.quitting = 1

        def dooneevent(self, mask = highLevelEventMask, timeout = 1*60):
                got, event = Evt.WaitNextEvent(mask, timeout)
                if got:
                        self.lowlevelhandler(event)

        def lowlevelhandler(self, event):
                what, message, when, where, modifiers = event
                h, v = where
                if what == kHighLevelEvent:
                        try:
                                AE.AEProcessAppleEvent(event)
                        except AE.Error, err:
                                msg = "High Level Event: %s %s" % \
                                        (`hex(message)`, `hex(h | (v<<16))`)
                                print 'AE error: ', err
                                print 'in', msg
                                traceback.print_exc()
                        return
                else:
                        print "Unhandled event:", event

        def callback_wrapper(self, _request, _reply):
                _parameters, _attributes = aetools.unpackevent(_request)
                _class = _attributes['evcl'].type
                _type = _attributes['evid'].type

                if self.ae_handlers.has_key((_class, _type)):
                        _function = self.ae_handlers[(_class, _type)]
                elif self.ae_handlers.has_key((_class, '****')):
                        _function = self.ae_handlers[(_class, '****')]
                elif self.ae_handlers.has_key(('****', '****')):
                        _function = self.ae_handlers[('****', '****')]
                else:
                        raise 'Cannot happen: AE callback without handler', (_class, _type)

                # XXXX Do key-to-name mapping here

                _parameters['_attributes'] = _attributes
                _parameters['_class'] = _class
                _parameters['_type'] = _type
                if _parameters.has_key('----'):
                        _object = _parameters['----']
                        del _parameters['----']
                        # The try/except that used to be here can mask programmer errors.
                        # Let the program crash, the programmer can always add a **args
                        # to the formal parameter list.
                        rv = _function(_object, **_parameters)
                else:
                        #Same try/except comment as above
                        rv = _function(**_parameters)

                if rv == None:
                        aetools.packevent(_reply, {})
                else:
                        aetools.packevent(_reply, {'----':rv})

        def open_app(self, **args):
                self._quit()

        def open_file(self, _object=None, **args):
                for alias in _object:
                        fsr = alias.FSResolveAlias(None)[0]
                        pathname = fsr.as_pathname()
                        sys.argv.append(pathname)
                self._quit()

        def other(self, _object=None, _class=None, _type=None, **args):
                print 'Ignore AppleEvent', (_class, _type), 'for', _object, 'Other args:', args

if __name__ == '__main__':
        ArgvCollector().mainloop()
        print "sys.argv=", sys.argv