Staging
v0.5.1
v0.5.1
aepack.py
"""Tools for use in AppleEvent clients and servers:
conversion between AE types and python types
pack(x) converts a Python object to an AEDesc object
unpack(desc) does the reverse
coerce(x, wanted_sample) coerces a python object to another python object
"""
#
# This code was originally written by Guido, and modified/extended by Jack
# to include the various types that were missing. The reference used is
# Apple Event Registry, chapter 9.
#
import struct
from Carbon import AE
from Carbon.AppleEvents import *
import MacOS
import Carbon.File
import io
import aetypes
from aetypes import mkenum, ObjectSpecifier
import os
# These ones seem to be missing from AppleEvents
# (they're in AERegistry.h)
#typeColorTable = b'clrt'
#typeDrawingArea = b'cdrw'
#typePixelMap = b'cpix'
#typePixelMapMinus = b'tpmm'
#typeRotation = b'trot'
#typeTextStyles = b'tsty'
#typeStyledText = b'STXT'
#typeAEText = b'tTXT'
#typeEnumeration = b'enum'
def b2i(byte_string):
result = 0
for byte in byte_string:
result <<= 8
result += byte
return result
#
# Some AE types are immedeately coerced into something
# we like better (and which is equivalent)
#
unpacker_coercions = {
b2i(typeComp) : typeFloat,
b2i(typeColorTable) : typeAEList,
b2i(typeDrawingArea) : typeAERecord,
b2i(typeFixed) : typeFloat,
b2i(typeExtended) : typeFloat,
b2i(typePixelMap) : typeAERecord,
b2i(typeRotation) : typeAERecord,
b2i(typeStyledText) : typeAERecord,
b2i(typeTextStyles) : typeAERecord,
};
#
# Some python types we need in the packer:
#
AEDescType = AE.AEDescType
FSSType = Carbon.File.FSSpecType
FSRefType = Carbon.File.FSRefType
AliasType = Carbon.File.AliasType
def packkey(ae, key, value):
if hasattr(key, 'which'):
keystr = key.which
elif hasattr(key, 'want'):
keystr = key.want
else:
keystr = key
ae.AEPutParamDesc(keystr, pack(value))
def pack(x, forcetype = None):
"""Pack a python object into an AE descriptor"""
if forcetype:
if isinstance(x, bytes):
return AE.AECreateDesc(forcetype, x)
else:
return pack(x).AECoerceDesc(forcetype)
if x == None:
return AE.AECreateDesc(b'null', '')
if isinstance(x, AEDescType):
return x
if isinstance(x, FSSType):
return AE.AECreateDesc(b'fss ', x.data)
if isinstance(x, FSRefType):
return AE.AECreateDesc(b'fsrf', x.data)
if isinstance(x, AliasType):
return AE.AECreateDesc(b'alis', x.data)
if isinstance(x, int):
return AE.AECreateDesc(b'long', struct.pack('l', x))
if isinstance(x, float):
return AE.AECreateDesc(b'doub', struct.pack('d', x))
if isinstance(x, (bytes, bytearray)):
return AE.AECreateDesc(b'TEXT', x)
if isinstance(x, str):
# See http://developer.apple.com/documentation/Carbon/Reference/Apple_Event_Manager/Reference/reference.html#//apple_ref/doc/constant_group/typeUnicodeText
# for the possible encodings.
data = x.encode('utf16')
if data[:2] == b'\xfe\xff':
data = data[2:]
return AE.AECreateDesc(b'utxt', data)
if isinstance(x, list):
lst = AE.AECreateList('', 0)
for item in x:
lst.AEPutDesc(0, pack(item))
return lst
if isinstance(x, dict):
record = AE.AECreateList('', 1)
for key, value in x.items():
packkey(record, key, value)
#record.AEPutParamDesc(key, pack(value))
return record
if isinstance(x, type) and issubclass(x, ObjectSpecifier):
# Note: we are getting a class object here, not an instance
return AE.AECreateDesc(b'type', x.want)
if hasattr(x, '__aepack__'):
return x.__aepack__()
if hasattr(x, 'which'):
return AE.AECreateDesc(b'TEXT', x.which)
if hasattr(x, 'want'):
return AE.AECreateDesc(b'TEXT', x.want)
return AE.AECreateDesc(b'TEXT', repr(x)) # Copout
def unpack(desc, formodulename=""):
"""Unpack an AE descriptor to a python object"""
t = desc.type
if b2i(t) in unpacker_coercions:
desc = desc.AECoerceDesc(unpacker_coercions[b2i(t)])
t = desc.type # This is a guess by Jack....
if t == typeAEList:
l = []
for i in range(desc.AECountItems()):
keyword, item = desc.AEGetNthDesc(i+1, b'****')
l.append(unpack(item, formodulename))
return l
if t == typeAERecord:
d = {}
for i in range(desc.AECountItems()):
keyword, item = desc.AEGetNthDesc(i+1, b'****')
d[b2i(keyword)] = unpack(item, formodulename)
return d
if t == typeAEText:
record = desc.AECoerceDesc(b'reco')
return mkaetext(unpack(record, formodulename))
if t == typeAlias:
return Carbon.File.Alias(rawdata=desc.data)
# typeAppleEvent returned as unknown
if t == typeBoolean:
return struct.unpack('b', desc.data)[0]
if t == typeChar:
return desc.data
if t == typeUnicodeText:
return str(desc.data, 'utf16')
# typeColorTable coerced to typeAEList
# typeComp coerced to extended
# typeData returned as unknown
# typeDrawingArea coerced to typeAERecord
if t == typeEnumeration:
return mkenum(desc.data)
# typeEPS returned as unknown
if t == typeFalse:
return 0
if t == typeFloat:
data = desc.data
return struct.unpack('d', data)[0]
if t == typeFSS:
return Carbon.File.FSSpec(rawdata=desc.data)
if t == typeFSRef:
return Carbon.File.FSRef(rawdata=desc.data)
if t == typeInsertionLoc:
record = desc.AECoerceDesc(b'reco')
return mkinsertionloc(unpack(record, formodulename))
# typeInteger equal to typeLongInteger
if t == typeIntlText:
script, language = struct.unpack('hh', desc.data[:4])
return aetypes.IntlText(script, language, desc.data[4:])
if t == typeIntlWritingCode:
script, language = struct.unpack('hh', desc.data)
return aetypes.IntlWritingCode(script, language)
if t == typeKeyword:
return mkkeyword(desc.data)
if t == typeLongInteger:
return struct.unpack('l', desc.data)[0]
if t == typeLongDateTime:
a, b = struct.unpack('lL', desc.data)
return (int(a) << 32) + b
if t == typeNull:
return None
if t == typeMagnitude:
v = struct.unpack('l', desc.data)
if v < 0:
v = 0x100000000 + v
return v
if t == typeObjectSpecifier:
record = desc.AECoerceDesc(b'reco')
# If we have been told the name of the module we are unpacking aedescs for,
# we can attempt to create the right type of python object from that module.
if formodulename:
return mkobjectfrommodule(unpack(record, formodulename), formodulename)
return mkobject(unpack(record, formodulename))
# typePict returned as unknown
# typePixelMap coerced to typeAERecord
# typePixelMapMinus returned as unknown
# typeProcessSerialNumber returned as unknown
if t == typeQDPoint:
v, h = struct.unpack('hh', desc.data)
return aetypes.QDPoint(v, h)
if t == typeQDRectangle:
v0, h0, v1, h1 = struct.unpack('hhhh', desc.data)
return aetypes.QDRectangle(v0, h0, v1, h1)
if t == typeRGBColor:
r, g, b = struct.unpack('hhh', desc.data)
return aetypes.RGBColor(r, g, b)
# typeRotation coerced to typeAERecord
# typeScrapStyles returned as unknown
# typeSessionID returned as unknown
if t == typeShortFloat:
return struct.unpack('f', desc.data)[0]
if t == typeShortInteger:
return struct.unpack('h', desc.data)[0]
# typeSMFloat identical to typeShortFloat
# typeSMInt indetical to typeShortInt
# typeStyledText coerced to typeAERecord
if t == typeTargetID:
return mktargetid(desc.data)
# typeTextStyles coerced to typeAERecord
# typeTIFF returned as unknown
if t == typeTrue:
return 1
if t == typeType:
return mktype(desc.data, formodulename)
#
# The following are special
#
if t == b'rang':
record = desc.AECoerceDesc(b'reco')
return mkrange(unpack(record, formodulename))
if t == b'cmpd':
record = desc.AECoerceDesc(b'reco')
return mkcomparison(unpack(record, formodulename))
if t == b'logi':
record = desc.AECoerceDesc(b'reco')
return mklogical(unpack(record, formodulename))
return mkunknown(desc.type, desc.data)
def coerce(data, egdata):
"""Coerce a python object to another type using the AE coercers"""
pdata = pack(data)
pegdata = pack(egdata)
pdata = pdata.AECoerceDesc(pegdata.type)
return unpack(pdata)
#
# Helper routines for unpack
#
def mktargetid(data):
sessionID = getlong(data[:4])
name = mkppcportrec(data[4:4+72])
location = mklocationnamerec(data[76:76+36])
rcvrName = mkppcportrec(data[112:112+72])
return sessionID, name, location, rcvrName
def mkppcportrec(rec):
namescript = getword(rec[:2])
name = getpstr(rec[2:2+33])
portkind = getword(rec[36:38])
if portkind == 1:
ctor = rec[38:42]
type = rec[42:46]
identity = (ctor, type)
else:
identity = getpstr(rec[38:38+33])
return namescript, name, portkind, identity
def mklocationnamerec(rec):
kind = getword(rec[:2])
stuff = rec[2:]
if kind == 0: stuff = None
if kind == 2: stuff = getpstr(stuff)
return kind, stuff
def mkunknown(type, data):
return aetypes.Unknown(type, data)
def getpstr(s):
return s[1:1+ord(s[0])]
def getlong(s):
return (ord(s[0])<<24) | (ord(s[1])<<16) | (ord(s[2])<<8) | ord(s[3])
def getword(s):
return (ord(s[0])<<8) | (ord(s[1])<<0)
def mkkeyword(keyword):
return aetypes.Keyword(keyword)
def mkrange(dict):
return aetypes.Range(dict[b2i(b'star')], dict[b2i(b'stop')])
def mkcomparison(dict):
return aetypes.Comparison(dict[b2i(b'obj1')],
dict[b2i(b'relo')].enum,
dict[b2i(b'obj2')])
def mklogical(dict):
return aetypes.Logical(dict[b2i(b'logc')], dict[b2i(b'term')])
def mkstyledtext(dict):
return aetypes.StyledText(dict[b2i(b'ksty')], dict[b2i(b'ktxt')])
def mkaetext(dict):
return aetypes.AEText(dict[b2i(keyAEScriptTag)],
dict[b2i(keyAEStyles)],
dict[b2i(keyAEText)])
def mkinsertionloc(dict):
return aetypes.InsertionLoc(dict[b2i(keyAEObject)],
dict[b2i(keyAEPosition)])
def mkobject(dict):
want = dict[b2i(b'want')].type
form = dict[b2i(b'form')].enum
seld = dict[b2i(b'seld')]
fr = dict[b2i(b'from')]
if form in (b'name', b'indx', b'rang', b'test'):
if want == b'text': return aetypes.Text(seld, fr)
if want == b'cha ': return aetypes.Character(seld, fr)
if want == b'cwor': return aetypes.Word(seld, fr)
if want == b'clin': return aetypes.Line(seld, fr)
if want == b'cpar': return aetypes.Paragraph(seld, fr)
if want == b'cwin': return aetypes.Window(seld, fr)
if want == b'docu': return aetypes.Document(seld, fr)
if want == b'file': return aetypes.File(seld, fr)
if want == b'cins': return aetypes.InsertionPoint(seld, fr)
if want == b'prop' and form == b'prop' and aetypes.IsType(seld):
return aetypes.Property(seld.type, fr)
return aetypes.ObjectSpecifier(want, form, seld, fr)
# Note by Jack: I'm not 100% sure of the following code. This was
# provided by Donovan Preston, but I wonder whether the assignment
# to __class__ is safe. Moreover, shouldn't there be a better
# initializer for the classes in the suites?
def mkobjectfrommodule(dict, modulename):
if (isinstance(dict[b2i(b'want')], type) and
issubclass(dict[b2i(b'want')], ObjectSpecifier)):
# The type has already been converted to Python. Convert back:-(
classtype = dict[b2i(b'want')]
dict[b2i(b'want')] = aetypes.mktype(classtype.want)
want = dict[b2i(b'want')].type
module = __import__(modulename)
codenamemapper = module._classdeclarations
classtype = codenamemapper.get(b2i(want), None)
newobj = mkobject(dict)
if classtype:
assert issubclass(classtype, ObjectSpecifier)
newobj.__class__ = classtype
return newobj
def mktype(typecode, modulename=None):
if modulename:
module = __import__(modulename)
codenamemapper = module._classdeclarations
classtype = codenamemapper.get(b2i(typecode), None)
if classtype:
return classtype
return aetypes.mktype(typecode)
