Mac/Lib/lib-toolbox/aepack.py

   1 """Tools for use in AppleEvent clients and servers:
   2 conversion between AE types and python types
   3
   4 pack(x) converts a Python object to an AEDesc object
   5 unpack(desc) does the reverse
   6 coerce(x, wanted_sample) coerces a python object to another python object
   7 """
   8
   9 #
  10 # This code was originally written by Guido, and modified/extended by Jack
  11 # to include the various types that were missing. The reference used is
  12 # Apple Event Registry, chapter 9.
  13 #
  14
  15 import struct
  16 import string
  17 import types
  18 from string import strip
  19 from types import *
  20 import AE
  21 from AppleEvents import *
  22 from AERegistry import *
  23 from AEObjects import *
  24 import MacOS
  25 import macfs
  26 import StringIO
  27 import aetypes
  28 from aetypes import mkenum, mktype
  29
  30 # These ones seem to be missing from AppleEvents
  31 # (they're in AERegistry.h)
  32
  33 #typeColorTable = 'clrt'
  34 #typeDrawingArea = 'cdrw'
  35 #typePixelMap = 'cpix'
  36 #typePixelMapMinus = 'tpmm'
  37 #typeRotation = 'trot'
  38 #typeTextStyles = 'tsty'
  39 #typeStyledText = 'STXT'
  40 #typeAEText = 'tTXT'
  41 #typeEnumeration = 'enum'
  42
  43 #
  44 # Some AE types are immedeately coerced into something
  45 # we like better (and which is equivalent)
  46 #
  47 unpacker_coercions = {
  48         typeComp : typeFloat,
  49         typeColorTable : typeAEList,
  50         typeDrawingArea : typeAERecord,
  51         typeFixed : typeFloat,
  52         typeExtended : typeFloat,
  53         typePixelMap : typeAERecord,
  54         typeRotation : typeAERecord,
  55         typeStyledText : typeAERecord,
  56         typeTextStyles : typeAERecord,
  57 };
  58
  59 #
  60 # Some python types we need in the packer:
  61 #
  62 AEDescType = type(AE.AECreateDesc('TEXT', ''))
  63 _sample_fss = macfs.FSSpec(':')
  64 _sample_alias = _sample_fss.NewAliasMinimal()
  65 FSSType = type(_sample_fss)
  66 AliasType = type(_sample_alias)
  67
  68 def pack(x, forcetype = None):
  69         """Pack a python object into an AE descriptor"""
  70
  71         if forcetype:
  72                 if type(x) is StringType:
  73                         return AE.AECreateDesc(forcetype, x)
  74                 else:
  75                         return pack(x).AECoerceDesc(forcetype)
  76
  77         if x == None:
  78                 return AE.AECreateDesc('null', '')
  79
  80         t = type(x)
  81         if t == AEDescType:
  82                 return x
  83         if t == FSSType:
  84                 return AE.AECreateDesc('fss ', x.data)
  85         if t == AliasType:
  86                 return AE.AECreateDesc('alis', x.data)
  87         if t == IntType:
  88                 return AE.AECreateDesc('long', struct.pack('l', x))
  89         if t == FloatType:
  90                 return AE.AECreateDesc('doub', struct.pack('d', x))
  91         if t == StringType:
  92                 return AE.AECreateDesc('TEXT', x)
  93         if t == ListType:
  94                 list = AE.AECreateList('', 0)
  95                 for item in x:
  96                         list.AEPutDesc(0, pack(item))
  97                 return list
  98         if t == DictionaryType:
  99                 record = AE.AECreateList('', 1)
 100                 for key, value in x.items():
 101                         record.AEPutParamDesc(key, pack(value))
 102                 return record
 103         if t == InstanceType and hasattr(x, '__aepack__'):
 104                 return x.__aepack__()
 105         return AE.AECreateDesc('TEXT', repr(x)) # Copout
 106
 107 def unpack(desc):
 108         """Unpack an AE descriptor to a python object"""
 109         t = desc.type
 110
 111         if unpacker_coercions.has_key(t):
 112                 desc = desc.AECoerceDesc(unpacker_coercions[t])
 113                 t = desc.type # This is a guess by Jack....
 114
 115         if t == typeAEList:
 116                 l = []
 117                 for i in range(desc.AECountItems()):
 118                         keyword, item = desc.AEGetNthDesc(i+1, '****')
 119                         l.append(unpack(item))
 120                 return l
 121         if t == typeAERecord:
 122                 d = {}
 123                 for i in range(desc.AECountItems()):
 124                         keyword, item = desc.AEGetNthDesc(i+1, '****')
 125                         d[keyword] = unpack(item)
 126                 return d
 127         if t == typeAEText:
 128                 record = desc.AECoerceDesc('reco')
 129                 return mkaetext(unpack(record))
 130         if t == typeAlias:
 131                 return macfs.RawAlias(desc.data)
 132         # typeAppleEvent returned as unknown
 133         if t == typeBoolean:
 134                 return struct.unpack('b', desc.data)[0]
 135         if t == typeChar:
 136                 return desc.data
 137         # typeColorTable coerced to typeAEList
 138         # typeComp coerced to extended
 139         # typeData returned as unknown
 140         # typeDrawingArea coerced to typeAERecord
 141         if t == typeEnumeration:
 142                 return mkenum(desc.data)
 143         # typeEPS returned as unknown
 144         if t == typeFalse:
 145                 return 0
 146         if t == typeFloat:
 147                 data = desc.data
 148                 return struct.unpack('d', data)[0]
 149         if t == typeFSS:
 150                 return macfs.RawFSSpec(desc.data)
 151         if t == typeInsertionLoc:
 152                 record = desc.AECoerceDesc('reco')
 153                 return mkinsertionloc(unpack(record))
 154         # typeInteger equal to typeLongInteger
 155         if t == typeIntlText:
 156                 script, language = struct.unpack('hh', desc.data[:4])
 157                 return aetypes.IntlText(script, language, desc.data[4:])
 158         if t == typeIntlWritingCode:
 159                 script, language = struct.unpack('hh', desc.data)
 160                 return aetypes.IntlWritingCode(script, language)
 161         if t == typeKeyword:
 162                 return mkkeyword(desc.data)
 163         if t == typeLongInteger:
 164                 return struct.unpack('l', desc.data)[0]
 165         if t == typeLongDateTime:
 166                 a, b = struct.unpack('lL', desc.data)
 167                 return (long(a) << 32) + b
 168         if t == typeNull:
 169                 return None
 170         if t == typeMagnitude:
 171                 v = struct.unpack('l', desc.data)
 172                 if v < 0:
 173                         v = 0x100000000L + v
 174                 return v
 175         if t == typeObjectSpecifier:
 176                 record = desc.AECoerceDesc('reco')
 177                 return mkobject(unpack(record))
 178         # typePict returned as unknown
 179         # typePixelMap coerced to typeAERecord
 180         # typePixelMapMinus returned as unknown
 181         # typeProcessSerialNumber returned as unknown
 182         if t == typeQDPoint:
 183                 v, h = struct.unpack('hh', desc.data)
 184                 return aetypes.QDPoint(v, h)
 185         if t == typeQDRectangle:
 186                 v0, h0, v1, h1 = struct.unpack('hhhh', desc.data)
 187                 return aetypes.QDRectangle(v0, h0, v1, h1)
 188         if t == typeRGBColor:
 189                 r, g, b = struct.unpack('hhh', desc.data)
 190                 return aetypes.RGBColor(r, g, b)
 191         # typeRotation coerced to typeAERecord
 192         # typeScrapStyles returned as unknown
 193         # typeSessionID returned as unknown
 194         if t == typeShortFloat:
 195                 return struct.unpack('f', desc.data)[0]
 196         if t == typeShortInteger:
 197                 return struct.unpack('h', desc.data)[0]
 198         # typeSMFloat identical to typeShortFloat
 199         # typeSMInt     indetical to typeShortInt
 200         # typeStyledText coerced to typeAERecord
 201         if t == typeTargetID:
 202                 return mktargetid(desc.data)
 203         # typeTextStyles coerced to typeAERecord
 204         # typeTIFF returned as unknown
 205         if t == typeTrue:
 206                 return 1
 207         if t == typeType:
 208                 return mktype(desc.data)
 209         #
 210         # The following are special
 211         #
 212         if t == 'rang':
 213                 record = desc.AECoerceDesc('reco')
 214                 return mkrange(unpack(record))
 215         if t == 'cmpd':
 216                 record = desc.AECoerceDesc('reco')
 217                 return mkcomparison(unpack(record))
 218         if t == 'logi':
 219                 record = desc.AECoerceDesc('reco')
 220                 return mklogical(unpack(record))
 221         return mkunknown(desc.type, desc.data)
 222
 223 def coerce(data, egdata):
 224         """Coerce a python object to another type using the AE coercers"""
 225         pdata = pack(data)
 226         pegdata = pack(egdata)
 227         pdata = pdata.AECoerceDesc(pegdata.type)
 228         return unpack(pdata)
 229
 230 #
 231 # Helper routines for unpack
 232 #
 233 def mktargetid(data):
 234         sessionID = getlong(data[:4])
 235         name = mkppcportrec(data[4:4+72])
 236         location = mklocationnamerec(data[76:76+36])
 237         rcvrName = mkppcportrec(data[112:112+72])
 238         return sessionID, name, location, rcvrName
 239
 240 def mkppcportrec(rec):
 241         namescript = getword(rec[:2])
 242         name = getpstr(rec[2:2+33])
 243         portkind = getword(rec[36:38])
 244         if portkind == 1:
 245                 ctor = rec[38:42]
 246                 type = rec[42:46]
 247                 identity = (ctor, type)
 248         else:
 249                 identity = getpstr(rec[38:38+33])
 250         return namescript, name, portkind, identity
 251
 252 def mklocationnamerec(rec):
 253         kind = getword(rec[:2])
 254         stuff = rec[2:]
 255         if kind == 0: stuff = None
 256         if kind == 2: stuff = getpstr(stuff)
 257         return kind, stuff
 258
 259 def mkunknown(type, data):
 260         return aetypes.Unknown(type, data)
 261
 262 def getpstr(s):
 263         return s[1:1+ord(s[0])]
 264
 265 def getlong(s):
 266         return (ord(s[0])<<24) | (ord(s[1])<<16) | (ord(s[2])<<8) | ord(s[3])
 267
 268 def getword(s):
 269         return (ord(s[0])<<8) | (ord(s[1])<<0)
 270
 271 def mkkeyword(keyword):
 272         return aetypes.Keyword(keyword)
 273
 274 def mkrange(dict):
 275         return aetypes.Range(dict['star'], dict['stop'])
 276
 277 def mkcomparison(dict):
 278         return aetypes.Comparison(dict['obj1'], dict['relo'].enum, dict['obj2'])
 279
 280 def mklogical(dict):
 281         return aetypes.Logical(dict['logc'], dict['term'])
 282
 283 def mkstyledtext(dict):
 284         return aetypes.StyledText(dict['ksty'], dict['ktxt'])
 285
 286 def mkaetext(dict):
 287         return aetypes.AEText(dict[keyAEScriptTag], dict[keyAEStyles], dict[keyAEText])
 288
 289 def mkinsertionloc(dict):
 290         return aetypes.InsertionLoc(dict[keyAEObject], dict[keyAEPosition])
 291
 292 def mkobject(dict):
 293         want = dict['want'].type
 294         form = dict['form'].enum
 295         seld = dict['seld']
 296         fr   = dict['from']
 297         if form in ('name', 'indx', 'rang', 'test'):
 298                 if want == 'text': return aetypes.Text(seld, fr)
 299                 if want == 'cha ': return aetypes.Character(seld, fr)
 300                 if want == 'cwor': return aetypes.Word(seld, fr)
 301                 if want == 'clin': return aetypes.Line(seld, fr)
 302                 if want == 'cpar': return aetypes.Paragraph(seld, fr)
 303                 if want == 'cwin': return aetypes.Window(seld, fr)
 304                 if want == 'docu': return aetypes.Document(seld, fr)
 305                 if want == 'file': return aetypes.File(seld, fr)
 306                 if want == 'cins': return aetypes.InsertionPoint(seld, fr)
 307         if want == 'prop' and form == 'prop' and aetypes.IsType(seld):
 308                 return aetypes.Property(seld.type, fr)
 309         return aetypes.ObjectSpecifier(want, form, seld, fr)
 310
 311 def _test():
 312         """Test program. Pack and unpack various things"""
 313         objs = [
 314                 'a string',
 315                 12,
 316                 12.0,
 317                 None,
 318                 ['a', 'list', 'of', 'strings'],
 319                 {'key1': 'value1', 'key2':'value2'},
 320                 macfs.FSSpec(':'),
 321                 macfs.FSSpec(':').NewAliasMinimal(),
 322                 aetypes.Enum('enum'),
 323                 aetypes.Type('type'),
 324                 aetypes.Keyword('kwrd'),
 325                 aetypes.Range(1, 10),
 326                 aetypes.Comparison(1, '<   ', 10),
 327                 aetypes.Logical('not ', 1),
 328                 # Cannot do StyledText
 329                 # Cannot do AEText
 330                 aetypes.IntlText(0, 0, 'international text'),
 331                 aetypes.IntlWritingCode(0,0),
 332                 aetypes.QDPoint(50,100),
 333                 aetypes.QDRectangle(50,100,150,200),
 334                 aetypes.RGBColor(0x7000, 0x6000, 0x5000),
 335                 aetypes.Unknown('xxxx', 'unknown type data'),
 336                 aetypes.Character(1),
 337                 aetypes.Character(2, aetypes.Line(2)),
 338         ]
 339         for o in objs:
 340                 print 'BEFORE', o, `o`
 341                 packed = pack(o)
 342                 unpacked = unpack(packed)
 343                 print 'AFTER ', unpacked, `unpacked`
 344         import sys
 345         sys.exit(1)
 346
 347 if __name__ == '__main__':
 348         _test()
 349