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