python/lib/pyasn1/pyasn1/type/namedtype.py

   1 # NamedType specification for constructed types
   2 import sys
   3 from pyasn1.type import tagmap
   4 from pyasn1 import error
   5
   6 class NamedType:
   7     isOptional = 0
   8     isDefaulted = 0
   9     def __init__(self, name, t):
  10         self.__name = name; self.__type = t
  11     def __repr__(self): return '%s(%s, %s)' % (
  12         self.__class__.__name__, self.__name, self.__type
  13         )
  14     def getType(self): return self.__type
  15     def getName(self): return self.__name
  16     def __getitem__(self, idx):
  17         if idx == 0: return self.__name
  18         if idx == 1: return self.__type
  19         raise IndexError()
  20
  21 class OptionalNamedType(NamedType):
  22     isOptional = 1
  23 class DefaultedNamedType(NamedType):
  24     isDefaulted = 1
  25
  26 class NamedTypes:
  27     def __init__(self, *namedTypes):
  28         self.__namedTypes = namedTypes
  29         self.__namedTypesLen = len(self.__namedTypes)
  30         self.__minTagSet = None
  31         self.__tagToPosIdx = {}; self.__nameToPosIdx = {}
  32         self.__tagMap = { False: None, True: None }
  33         self.__ambigiousTypes = {}
  34
  35     def __repr__(self):
  36         r = '%s(' % self.__class__.__name__
  37         for n in self.__namedTypes:
  38             r = r + '%r, ' % (n,)
  39         return r + ')'
  40
  41     def __getitem__(self, idx): return self.__namedTypes[idx]
  42
  43     if sys.version_info[0] <= 2:
  44         def __nonzero__(self): return bool(self.__namedTypesLen)
  45     else:
  46         def __bool__(self): return bool(self.__namedTypesLen)
  47     def __len__(self): return self.__namedTypesLen
  48
  49     def getTypeByPosition(self, idx):
  50         if idx < 0 or idx >= self.__namedTypesLen:
  51             raise error.PyAsn1Error('Type position out of range')
  52         else:
  53             return self.__namedTypes[idx].getType()
  54
  55     def getPositionByType(self, tagSet):
  56         if not self.__tagToPosIdx:
  57             idx = self.__namedTypesLen
  58             while idx > 0:
  59                 idx = idx - 1
  60                 tagMap = self.__namedTypes[idx].getType().getTagMap()
  61                 for t in tagMap.getPosMap():
  62                     if t in self.__tagToPosIdx:
  63                         raise error.PyAsn1Error('Duplicate type %s' % (t,))
  64                     self.__tagToPosIdx[t] = idx
  65         try:
  66             return self.__tagToPosIdx[tagSet]
  67         except KeyError:
  68             raise error.PyAsn1Error('Type %s not found' % (tagSet,))
  69
  70     def getNameByPosition(self, idx):
  71         try:
  72             return self.__namedTypes[idx].getName()
  73         except IndexError:
  74             raise error.PyAsn1Error('Type position out of range')
  75     def getPositionByName(self, name):
  76         if not self.__nameToPosIdx:
  77             idx = self.__namedTypesLen
  78             while idx > 0:
  79                 idx = idx - 1
  80                 n = self.__namedTypes[idx].getName()
  81                 if n in self.__nameToPosIdx:
  82                     raise error.PyAsn1Error('Duplicate name %s' % (n,))
  83                 self.__nameToPosIdx[n] = idx
  84         try:
  85             return self.__nameToPosIdx[name]
  86         except KeyError:
  87             raise error.PyAsn1Error('Name %s not found' % (name,))
  88
  89     def __buildAmbigiousTagMap(self):
  90         ambigiousTypes = ()
  91         idx = self.__namedTypesLen
  92         while idx > 0:
  93             idx = idx - 1
  94             t = self.__namedTypes[idx]
  95             if t.isOptional or t.isDefaulted:
  96                 ambigiousTypes = (t, ) + ambigiousTypes
  97             else:
  98                 ambigiousTypes = (t, )
  99             self.__ambigiousTypes[idx] = NamedTypes(*ambigiousTypes)
 100
 101     def getTagMapNearPosition(self, idx):
 102         if not self.__ambigiousTypes: self.__buildAmbigiousTagMap()
 103         try:
 104             return self.__ambigiousTypes[idx].getTagMap()
 105         except KeyError:
 106             raise error.PyAsn1Error('Type position out of range')
 107
 108     def getPositionNearType(self, tagSet, idx):
 109         if not self.__ambigiousTypes: self.__buildAmbigiousTagMap()
 110         try:
 111             return idx+self.__ambigiousTypes[idx].getPositionByType(tagSet)
 112         except KeyError:
 113             raise error.PyAsn1Error('Type position out of range')
 114
 115     def genMinTagSet(self):
 116         if self.__minTagSet is None:
 117             for t in self.__namedTypes:
 118                 __type = t.getType()
 119                 tagSet = getattr(__type,'getMinTagSet',__type.getTagSet)()
 120                 if self.__minTagSet is None or tagSet < self.__minTagSet:
 121                     self.__minTagSet = tagSet
 122         return self.__minTagSet
 123
 124     def getTagMap(self, uniq=False):
 125         if self.__tagMap[uniq] is None:
 126             tagMap = tagmap.TagMap()
 127             for nt in self.__namedTypes:
 128                 tagMap = tagMap.clone(
 129                     nt.getType(), nt.getType().getTagMap(), uniq
 130                     )
 131             self.__tagMap[uniq] = tagMap
 132         return self.__tagMap[uniq]