"""Buffers used to hold null-terminated strings."""from bgenBuffer import FixedOutputBufferTypefrom bgenStackBuffer import StackOutputBufferTypefrom bgenHeapBuffer import HeapOutputBufferTypeclass StringBufferMixIn:	"""Mix-in class to create various string buffer types.	Strings are character arrays terminated by a null byte.	(For input, this is also covered by stringptr.)	For output, there are again three variants:	- Fixed: size is a constant given in the documentation; or	- Stack: size is passed to the C function but we decide on a size at	  code generation time so we can still allocate on the heap); or	- Heap: size is passed to the C function and we let the Python caller	  pass a size.	(Note that this doesn't cover output parameters in which a string	pointer is returned.  These are actually easier (no allocation) but far	less common.  I'll write the classes when there is demand.)	"""		def declareSize(self, name):		pass		def getargsFormat(self):		return "s"		def getargsArgs(self, name):		return "&%s__in__" % name	def mkvalueFormat(self):		return "s"	def mkvalueArgs(self, name):		return "%s__out__" % nameclass FixedOutputStringType(StringBufferMixIn, FixedOutputBufferType):	"""Null-terminated output string -- passed without size.	Instantiate with buffer size as parameter.	"""class StackOutputStringType(StringBufferMixIn, StackOutputBufferType):	"""Null-terminated output string -- passed as (buffer, size).	Instantiate with buffer size as parameter.	"""class HeapOutputStringType(StringBufferMixIn, HeapOutputBufferType):	"""Null-terminated output string -- passed as (buffer, size).	Instantiate without parameters.	Call from Python with buffer size.	"""