/Scripts/Marshall/StringMarshaller.py

"""

This source file is part of HGamer3D

(A project to enable 3D game development in Haskell)

For the latest info, see http://www.althainz.de/HGamer3D.html



(c) 2011 Peter Althainz



Licensed under the Apache License, Version 2.0 (the "License");

you may not use this file except in compliance with the License.

You may obtain a copy of the License at



    http://www.apache.org/licenses/LICENSE-2.0



Unless required by applicable law or agreed to in writing, software

distributed under the License is distributed on an "AS IS" BASIS,

WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

See the License for the specific language governing permissions and

limitations under the License.

"""



# StringMarshaller.py



import os, re, sys

import Config, BasicMarshaller



class StringMarshaller(BasicMarshaller.BasicMarshaller):

	"""

	marshalling of Simple c/Haskell types

	

	Transformation Table for "string" Types:

	----------------------------------------



	----------------+--------+-----------+------------------------------------------------------+-------+------------------------------------------+

	cpp-type        + In/Out + x_ctype   + CtoCpp                                               + vcpm  + CpptoC                                   +

	----------------+--------+-----------+------------------------------------------------------+-------+------------------------------------------+

	base *          | In     | ctype*    | base *name_cpp = (base *) in_name_c;                 | -     | -                                        |

	const base *    | In     | ctype*    | const base *name_cpp = (const base *) in_name_c;     | -     | -                                        |

	----------------+--------+-----------+------------------------------------------------------+-------+------------------------------------------+



	x_type is in/out c-type

	"""



	def getPossibleModifications(self):

		"""string types currently support only in and const out for overwriteOut"""

		return {

			# const, ref, pointer, doublepointer 

			"in" : (False, False, True, False),   # input, simple pointer

			"const" : (True, False, True, False), # input/output const pointer

		}

		

#

# here are coming the marshalling routines

#





	def vcpm(self):

		"""

		modifier before the variable name, for the invocation of the function,

		depends on the difference between the parameter type and the variable

		type.

		"""

		return ""





	def ctype(self, overwriteOut):

		"""

		type for C-function declaration, 

		overwriteIsOut: the parameter is an out parameter, independent

		of the mod function (its a function return value)

		"""

		return self.typeConfig.getProp("ctype") + "*"



			

	def fromCtoCpp(self, cname, cppname, overwriteOut):

		""" 

		returns lines of code, to create a cpp variable, transform the 

		input C value to this type. If it is a out variable, transformation

		of input variable not needed, but creation of cpp variable still needed.

		overwriteOut: if True, this is a out variable, independent of self.mod

		"""

		if overwriteOut and self.mod == "in":

			print "overwriteOut for string type:", self.cpptype()

			sys.exit(-1)

		

		if overwriteOut and self.mod == "const":

			return "const " + self.baseType + " *" + cppname + ";\n"

		else:

			return self.baseType + " *" + cppname + " = (" + self.baseType + "*) " + cname + ";\n"



			

	def fromCpptoC(self, cname, cppname, overwriteOut):

		"""

		returns lines of code, to transform the cpp value to the output

		c value, only needed in case of out variable.

		overwriteOut: if True, this is a out variable, independent of self.mod

		"""

		if overwriteOut and self.mod == "in":

			print "overwriteOut for string type", self.cpptype()

			sys.exit(-1)

		

		if overwriteOut and self.mod == "const":

			if (self.baseType == "wchar_t"):

				outtext = "if (wcslen( (" + self.baseType + "*) " + cppname + ") < (512 * 64 - 2))  { \n"

				outtext = outtext + "wcscpy(" + cname + ", (" + self.baseType + "*) " + cppname + "); } else {\n"

				outtext = outtext + "wcscpy(" + cname + ", L\"error: outstring larger then 64k\");};\n"

				return outtext

			else:

				outtext = "if (strlen( (" + self.baseType + "*) " + cppname + ") < (1024 * 64 - 1))  { \n"

				outtext = outtext + "strcpy(" + cname + ", (" + self.baseType + "*) " + cppname + "); } else {\n"

				outtext = outtext + "strcpy(" + cname + ", \"error: outstring larger then 64k\");};\n"

				return outtext

		else:

			return ""

					

	def chsFuncDefinition(self, overwriteOut):

		"""provides the marshalling string within the C2HS func definition"""

		if overwriteOut and self.mod == "in":

			print "overwriteOut for string type", self.cpptype()

			sys.exit(-1)

		

		conf = self.typeConfig

		if overwriteOut and self.mod == "const":

			return "alloc64k- `" + conf.getProp("htype") + "' " + conf.getProp("outmarsh") + "*"	

		else:

			return conf.getProp("inmarsh") + "* `" + conf.getProp("htype") + "' "