""" Wrap C++ class methods and constructods. """ import warnings import traceback from copy import copy from typehandlers.base import ForwardWrapperBase, ReverseWrapperBase, \ join_ctype_and_name, CodeGenerationError from typehandlers.base import ReturnValue, Parameter from typehandlers import codesink import overloading import settings import utils from cppexception import CppException class CppMethod(ForwardWrapperBase): """ Class that generates a wrapper to a C++ class method """ def __init__(self, method_name, return_value, parameters, is_static=False, template_parameters=(), is_virtual=None, is_const=False, unblock_threads=None, is_pure_virtual=False, custom_template_method_name=None, visibility='public', custom_name=None, deprecated=False, docstring=None, throw=()): """ Create an object the generates code to wrap a C++ class method. :param return_value: the method return value :type return_value: L{ReturnValue} :param method_name: name of the method :param parameters: the method parameters :type parameters: list of :class:`pybindgen.typehandlers.base.Parameter` :param is_static: whether it is a static method :param template_parameters: optional list of template parameters needed to invoke the method :type template_parameters: list of strings, each element a template parameter expression :param is_virtual: whether the method is virtual (pure or not) :param is_const: whether the method has a const modifier on it :param unblock_threads: whether to release the Python GIL around the method call or not. If None or omitted, use global settings. Releasing the GIL has a small performance penalty, but is recommended if the method is expected to take considerable time to complete, because otherwise no other Python thread is allowed to run until the method completes. :param is_pure_virtual: whether the method is defined as "pure virtual", i.e. virtual method with no default implementation in the class being wrapped. :param custom_name: alternate name to give to the method, in python side. :param custom_template_method_name: (deprecated) same as parameter 'custom_name'. :param visibility: visibility of the method within the C++ class :type visibility: a string (allowed values are 'public', 'protected', 'private') :param deprecated: deprecation state for this API: - False: Not deprecated - True: Deprecated - "message": Deprecated, and deprecation warning contains the given message :param throw: list of C++ exceptions that the function may throw :type throw: list of L{CppException} """ self.stack_where_defined = traceback.extract_stack() ## backward compatibility check if isinstance(return_value, str) and isinstance(method_name, ReturnValue): warnings.warn("CppMethod has changed API; see the API documentation (but trying to correct...)", DeprecationWarning, stacklevel=2) method_name, return_value = return_value, method_name # bug 399870 if is_virtual is None: is_virtual = is_pure_virtual if return_value is None: return_value = ReturnValue.new('void') if unblock_threads is None: unblock_threads = settings.unblock_threads assert visibility in ['public', 'protected', 'private'] self.visibility = visibility self.method_name = method_name self.is_static = is_static self.is_virtual = is_virtual self.is_pure_virtual = is_pure_virtual self.is_const = is_const self.template_parameters = template_parameters self.custom_name = (custom_name or custom_template_method_name) #self.static_decl = True self._class = None self._helper_class = None self.docstring = docstring self.wrapper_base_name = None self.wrapper_actual_name = None self.return_value = None self.parameters = None return_value = utils.eval_retval(return_value, self) parameters = [utils.eval_param(param, self) for param in parameters] super(CppMethod, self).__init__( return_value, parameters, "return NULL;", "return NULL;", unblock_threads=unblock_threads) self.deprecated = deprecated for t in throw: assert isinstance(t, CppException) self.throw = list(throw) self.custodians_and_wards = [] # list of (custodian, ward, postcall) cppclass_typehandlers.scan_custodians_and_wards(self) def add_custodian_and_ward(self, custodian, ward, postcall=None): """Add a custodian/ward relationship to the method wrapper A custodian/ward relationship is one where one object (custodian) keeps a references to another object (ward), thus keeping it alive. When the custodian is destroyed, the reference to the ward is released, allowing the ward to be freed if no other reference to it is being kept by the user code. Please note that custodian/ward manages the lifecycle of Python wrappers, not the C/C++ objects referenced by the wrappers. In most cases, the wrapper owns the C/C++ object, and so the lifecycle of the C/C++ object is also managed by this. However, there are cases when a Python wrapper does not own the underlying C/C++ object, only references it. The custodian and ward objects are indicated by an integer with the following meaning: - C{-1}: the return value of the function - C{0}: the instance of the method (self) - value > 0: the nth parameter of the function, starting at 1 :parameter custodian: number of the object that assumes the role of custodian :parameter ward: number of the object that assumes the role of ward :parameter postcall: if True, the relationship is added after the C function call, if False it is added before the call. If not given, the value False is assumed if the return value is not involved, else postcall=True is used. """ if custodian == -1 or ward == -1: if postcall is None: postcall = True if not postcall: raise TypeConfigurationError("custodian/ward policy must be postcall " "when a return value is involved") else: if postcall is None: postcall = False self.custodians_and_wards.append((custodian, ward, postcall)) def set_helper_class(self, helper_class): "Set the C++ helper class, which is used for overriding virtual methods" self._helper_class = helper_class self.wrapper_base_name = "%s::_wrap_%s" % (self._helper_class.name, self.method_name) def get_helper_class(self): "Get the C++ helper class, which is used for overriding virtual methods" return self._helper_class helper_class = property(get_helper_class, set_helper_class) def matches_signature(self, other): if self.mangled_name != other.mangled_name: return False if len(self.parameters) != len(other.parameters): return False for param1, param2 in zip(self.parameters, other.parameters): if param1.ctype != param2.ctype: return False if bool(self.is_const) != bool(other.is_const): return False return True def set_custom_name(self, custom_name): if custom_name is None: self.mangled_name = utils.get_mangled_name(self.method_name, self.template_parameters) else: self.mangled_name = custom_name custom_name = property(None, set_custom_name) def clone(self): """Creates a semi-deep copy of this method wrapper. The returned method wrapper clone contains copies of all parameters, so they can be modified at will. """ meth = CppMethod(self.method_name, self.return_value, [copy(param) for param in self.parameters], is_static=self.is_static, template_parameters=self.template_parameters, is_virtual=self.is_virtual, is_pure_virtual=self.is_pure_virtual, is_const=self.is_const, visibility=self.visibility) meth._class = self._class meth.docstring = self.docstring meth.wrapper_base_name = self.wrapper_base_name meth.wrapper_actual_name = self.wrapper_actual_name return meth def set_class(self, class_): """set the class object this method belongs to""" self._class = class_ self.wrapper_base_name = "_wrap_%s_%s" % ( class_.pystruct, self.mangled_name) def get_class(self): """get the class object this method belongs to""" return self._class class_ = property(get_class, set_class) def generate_call(self, class_=None): "virtual method implementation; do not call" #assert isinstance(class_, CppClass) if class_ is None: class_ = self._class if self.template_parameters: template_params = '< %s >' % ', '.join(self.template_parameters) else: template_params = '' if self.return_value.ctype == 'void': retval_assign = '' else: if self.return_value.REQUIRES_ASSIGNMENT_CONSTRUCTOR: retval_assign = '%s retval = ' % (self.return_value.ctype,) else: retval_assign = 'retval = ' if class_.helper_class is not None and self.is_virtual and not self.is_pure_virtual\ and not settings._get_deprecated_virtuals(): helper = self.before_call.declare_variable(type_="%s *" % class_.helper_class.name, name="helper_class", initializer=( "dynamic_cast<%s*> (self->obj)" % class_.helper_class.name)) else: helper = None if self.is_static: method = '%s::%s%s' % (class_.full_name, self.method_name, template_params) else: method = 'self->obj->%s%s' % (self.method_name, template_params) if self.throw: self.before_call.write_code('try\n{') self.before_call.indent() if self.is_static: self.before_call.write_code(retval_assign + ( '%s::%s%s(%s);' % (class_.full_name, self.method_name, template_params, ", ".join(self.call_params)))) else: if helper is None: self.before_call.write_code(retval_assign + ( 'self->obj->%s%s(%s);' % (self.method_name, template_params, ", ".join(self.call_params)))) else: self.before_call.write_code(retval_assign + ( '(%s == NULL)? (self->obj->%s%s(%s)) : (self->obj->%s::%s%s(%s));' % (helper, self.method_name, template_params, ", ".join(self.call_params), class_.full_name, self.method_name, template_params, ", ".join(self.call_params) ))) if self.throw: for exc in self.throw: self.before_call.unindent() self.before_call.write_code('} catch (%s const &exc) {' % exc.full_name) self.before_call.indent() self.before_call.write_cleanup() exc.write_convert_to_python(self.before_call, 'exc') self.before_call.write_code('return NULL;') self.before_call.unindent() self.before_call.write_code('}') def _before_call_hook(self): "hook that post-processes parameters and check for custodian= CppClass parameters" cppclass_typehandlers.implement_parameter_custodians_precall(self) def _before_return_hook(self): """hook that post-processes parameters and check for custodian= CppClass parameters""" cppclass_typehandlers.implement_parameter_custodians_postcall(self) def _get_pystruct(self): # When a method is used in the context of a helper class, we # should use the pystruct of the helper class' class. # # self.class_: original base class where the method is defined # self._helper_class.class_: subclass that is inheriting the method # if self._helper_class is None: return self.class_.pystruct else: return self._helper_class.class_.pystruct def get_wrapper_signature(self, wrapper_name, extra_wrapper_params=()): flags = self.get_py_method_def_flags() self.wrapper_actual_name = wrapper_name self.wrapper_return = "PyObject *" if 'METH_STATIC' in flags: _self_name = 'PYBINDGEN_UNUSED(dummy)' else: _self_name = 'self' # if extra_wrapper_params: # extra = ', '.join([''] + list(extra_wrapper_params)) # else: # extra = '' if 'METH_VARARGS' in flags: if 'METH_KEYWORDS' in flags: self.wrapper_args = ["%s *%s" % (self._get_pystruct(), _self_name), "PyObject *args", "PyObject *kwargs"] else: assert not extra_wrapper_params, \ "extra_wrapper_params can only be used with"\ " full varargs/kwargs wrappers" self.wrapper_args = ["%s *%s" % (self._get_pystruct(), _self_name), "PyObject *args"] else: assert not extra_wrapper_params, \ "extra_wrapper_params can only be used with full varargs/kwargs wrappers" if 'METH_STATIC' in flags: self.wrapper_args = ['void'] else: self.wrapper_args = ["%s *%s" % (self._get_pystruct(), _self_name)] self.wrapper_args.extend(extra_wrapper_params) return self.wrapper_return, "%s(%s)" % (self.wrapper_actual_name, ', '.join(self.wrapper_args)) def generate(self, code_sink, wrapper_name=None, extra_wrapper_params=()): """ Generates the wrapper code code_sink -- a CodeSink instance that will receive the generated code method_name -- actual name the method will get extra_wrapper_params -- extra parameters the wrapper function should receive Returns the corresponding PyMethodDef entry string. """ if self.throw: # Bug #780945 self.return_value.REQUIRES_ASSIGNMENT_CONSTRUCTOR = False self.reset_code_generation_state() class_ = self.class_ #assert isinstance(class_, CppClass) tmp_sink = codesink.MemoryCodeSink() self.generate_body(tmp_sink, gen_call_params=[class_]) if wrapper_name is None: self.wrapper_actual_name = self.wrapper_base_name else: self.wrapper_actual_name = wrapper_name self.get_wrapper_signature(self.wrapper_actual_name, extra_wrapper_params) self.write_open_wrapper(code_sink)#, add_static=self.static_decl) tmp_sink.flush_to(code_sink) self.write_close_wrapper(code_sink) def get_py_method_def_flags(self): "Get the PyMethodDef flags suitable for this method" flags = super(CppMethod, self).get_py_method_def_flags() if self.is_static: flags.append('METH_STATIC') return flags def get_py_method_def(self, method_name): "Get the PyMethodDef entry suitable for this method" flags = self.get_py_method_def_flags() return "{(char *) \"%s\", (PyCFunction) %s, %s, %s }," % \ (method_name, self.wrapper_actual_name, '|'.join(flags), (self.docstring is None and "NULL" or ('"'+self.docstring+'"'))) def __str__(self): if self.class_ is None: cls_name = "???" else: cls_name = self.class_.full_name if self.is_const: const = ' const' else: const = '' if self.is_virtual: virtual = "virtual " else: virtual = '' if self.is_pure_virtual: pure_virtual = " = 0" else: pure_virtual = '' if self.return_value is None: retval = "retval?" else: retval = self.return_value.ctype if self.parameters is None: params = 'params?' else: params = ', '.join(["%s %s" % (param.ctype, param.name) for param in self.parameters]) return ("%s: %s%s %s::%s (%s)%s%s;" % (self.visibility, virtual, retval, cls_name, self.method_name, params, const, pure_virtual)) class CppOverloadedMethod(overloading.OverloadedWrapper): "Support class for overloaded methods" RETURN_TYPE = 'PyObject *' ERROR_RETURN = 'return NULL;' class DummyReturnValue(ReturnValue): CTYPES = [] """ A 'dummy' return value object used for modelling methods that have incomplete or incorrect parameters or return values. """ def __init__(self, arg): """ Accepts either a ReturnValue object or a tuple as sole parameter. In case it's a tuple, it is assumed to be a retval spec (\\*args, \\*\\*kwargs). """ if isinstance(arg, ReturnValue): super(DummyReturnValue, self).__init__(arg.ctype) else: args, kwargs = utils.parse_retval_spec(arg) super(DummyReturnValue, self).__init__(args[0]) def convert_c_to_python(self, wrapper): raise TypeError("this is a DummyReturnValue") def convert_python_to_c(self, wrapper): raise TypeError("this is a DummyReturnValue") def get_c_error_return(self): return '' class DummyParameter(Parameter): CTYPES = [] DIRECTIONS = [Parameter.DIRECTION_IN, Parameter.DIRECTION_OUT, Parameter.DIRECTION_INOUT] """ A 'dummy' parameter object used for modelling methods that have incomplete or incorrect parameters or return values. """ def __init__(self, arg): """ Accepts either a Parameter object or a tuple as sole parameter. In case it's a tuple, it is assumed to be a retval spec (\\*args, \\*\\*kwargs). """ if isinstance(arg, ReturnValue): super(DummyParameter, self).__init__(arg.ctype) else: args, kwargs = utils.parse_param_spec(arg) super(DummyParameter, self).__init__(args[0], args[1]) def convert_c_to_python(self, wrapper): raise TypeError("this is a DummyParameter") def convert_python_to_c(self, wrapper): raise TypeError("this is a DummyParameter") class CppDummyMethod(CppMethod): """ A 'dummy' method; cannot be generated due to incomple or incorrect parameters, but is added to the class to model the missing method. """ def __init__(self, method_name, return_value, parameters, *args, **kwargs): return_value = DummyReturnValue(return_value) parameters = [DummyParameter(p) for p in parameters] super(CppDummyMethod, self).__init__(method_name, return_value, parameters, *args, **kwargs) class CppConstructor(ForwardWrapperBase): """ Class that generates a wrapper to a C++ class constructor. Such wrapper is used as the python class __init__ method. """ def __init__(self, parameters, unblock_threads=None, visibility='public', deprecated=False, throw=()): """ :param parameters: the constructor parameters :param deprecated: deprecation state for this API: False=Not deprecated; True=Deprecated; "message"=Deprecated, and deprecation warning contains the given message :param throw: list of C++ exceptions that the constructor may throw :type throw: list of :class:`pybindgen.cppexception.CppException` """ self.stack_where_defined = traceback.extract_stack() if unblock_threads is None: unblock_threads = settings.unblock_threads parameters = [utils.eval_param(param, self) for param in parameters] super(CppConstructor, self).__init__( None, parameters, "return -1;", "return -1;", force_parse=ForwardWrapperBase.PARSE_TUPLE_AND_KEYWORDS, unblock_threads=unblock_threads) self.deprecated = deprecated assert visibility in ['public', 'protected', 'private'] self.visibility = visibility self.wrapper_base_name = None self.wrapper_actual_name = None self._class = None for t in throw: assert isinstance(t, CppException) self.throw = list(throw) self.custodians_and_wards = [] # list of (custodian, ward, postcall) cppclass_typehandlers.scan_custodians_and_wards(self) def add_custodian_and_ward(self, custodian, ward, postcall=None): """Add a custodian/ward relationship to the constructor wrapper A custodian/ward relationship is one where one object (custodian) keeps a references to another object (ward), thus keeping it alive. When the custodian is destroyed, the reference to the ward is released, allowing the ward to be freed if no other reference to it is being kept by the user code. Please note that custodian/ward manages the lifecycle of Python wrappers, not the C/C++ objects referenced by the wrappers. In most cases, the wrapper owns the C/C++ object, and so the lifecycle of the C/C++ object is also managed by this. However, there are cases when a Python wrapper does not own the underlying C/C++ object, only references it. The custodian and ward objects are indicated by an integer with the following meaning: - C{0}: the object being constructed (self) - value > 0: the nth parameter of the function, starting at 1 :parameter custodian: number of the object that assumes the role of custodian :parameter ward: number of the object that assumes the role of ward :parameter postcall: if True, the relationship is added after the C function call, if False it is added before the call. If not given, the value False is assumed if the return value is not involved, else postcall=True is used. """ if custodian == -1 or ward == -1: if postcall is None: postcall = True if not postcall: raise TypeConfigurationError("custodian/ward policy must be postcall " "when a return value is involved") else: if postcall is None: postcall = False self.custodians_and_wards.append((custodian, ward, postcall)) def clone(self): """ Creates a semi-deep copy of this constructor wrapper. The returned constructor wrapper clone contains copies of all parameters, so they can be modified at will. """ meth = type(self)([copy(param) for param in self.parameters]) meth._class = self._class meth.wrapper_base_name = self.wrapper_base_name meth.wrapper_actual_name = self.wrapper_actual_name return meth def set_class(self, class_): "Set the class wrapper object (CppClass)" self._class = class_ self.wrapper_base_name = "_wrap_%s__tp_init" % ( class_.pystruct,) def get_class(self): "Get the class wrapper object (CppClass)" return self._class class_ = property(get_class, set_class) def generate_call(self, class_=None): "virtual method implementation; do not call" if class_ is None: class_ = self._class if self.throw: self.before_call.write_code('try\n{') self.before_call.indent() #assert isinstance(class_, CppClass) if class_.helper_class is None: class_.write_create_instance(self.before_call, "self->obj", ", ".join(self.call_params)) class_.write_post_instance_creation_code(self.before_call, "self->obj", ", ".join(self.call_params)) self.before_call.write_code("self->flags = PYBINDGEN_WRAPPER_FLAG_NONE;") else: ## We should only create a helper class instance when ## being called from a user python subclass. self.before_call.write_code("if (self->ob_type != &%s)" % class_.pytypestruct) self.before_call.write_code("{") self.before_call.indent() class_.write_create_instance(self.before_call, "self->obj", ", ".join(self.call_params), class_.helper_class.name) self.before_call.write_code("self->flags = PYBINDGEN_WRAPPER_FLAG_NONE;") self.before_call.write_code('((%s*) self->obj)->set_pyobj((PyObject *)self);' % class_.helper_class.name) class_.write_post_instance_creation_code(self.before_call, "self->obj", ", ".join(self.call_params), class_.helper_class.name) self.before_call.unindent() self.before_call.write_code("} else {") self.before_call.indent() self.before_call.write_code("// visibility: %r" % self.visibility) try: if self.visibility not in ['public']: raise CodeGenerationError("private/protected constructor") class_.get_construct_name() except CodeGenerationError: self.before_call.write_code('PyErr_SetString(PyExc_TypeError, "class \'%s\' ' 'cannot be constructed");' % class_.name) self.before_call.write_code('return -1;') else: class_.write_create_instance(self.before_call, "self->obj", ", ".join(self.call_params)) self.before_call.write_code("self->flags = PYBINDGEN_WRAPPER_FLAG_NONE;") class_.write_post_instance_creation_code(self.before_call, "self->obj", ", ".join(self.call_params)) self.before_call.unindent() self.before_call.write_code("}") if self.throw: for exc in self.throw: self.before_call.unindent() self.before_call.write_code('} catch (%s const &exc) {' % exc.full_name) self.before_call.indent() self.before_call.write_cleanup() exc.write_convert_to_python(self.before_call, 'exc') self.before_call.write_code('return -1;') self.before_call.unindent() self.before_call.write_code('}') def _before_call_hook(self): "hook that post-processes parameters and check for custodian= CppClass parameters" cppclass_typehandlers.implement_parameter_custodians_precall(self) def _before_return_hook(self): "hook that post-processes parameters and check for custodian= CppClass parameters" cppclass_typehandlers.implement_parameter_custodians_postcall(self) def generate(self, code_sink, wrapper_name=None, extra_wrapper_params=()): """ Generates the wrapper code :param code_sink: a CodeSink instance that will receive the generated code :returns: the wrapper function name. """ if self.visibility == 'private': raise utils.SkipWrapper("Class %r has a private constructor ->" " cannot generate a constructor for it" % self._class.full_name) elif self.visibility == 'protected': if self._class.helper_class is None: raise utils.SkipWrapper("Class %r has a protected constructor and no helper class" " -> cannot generate a constructor for it" % self._class.full_name) #assert isinstance(class_, CppClass) tmp_sink = codesink.MemoryCodeSink() assert self._class is not None self.generate_body(tmp_sink, gen_call_params=[self._class]) assert ((self.parse_params.get_parameters() == ['""']) or self.parse_params.get_keywords() is not None), \ ("something went wrong with the type handlers;" " constructors need parameter names, " "yet no names were given for the class %s constructor" % self._class.name) if wrapper_name is None: self.wrapper_actual_name = self.wrapper_base_name else: self.wrapper_actual_name = wrapper_name self.wrapper_return = 'static int' self.wrapper_args = ["%s *self" % self._class.pystruct, "PyObject *args", "PyObject *kwargs"] self.wrapper_args.extend(extra_wrapper_params) self.write_open_wrapper(code_sink) tmp_sink.flush_to(code_sink) code_sink.writeln('return 0;') self.write_close_wrapper(code_sink) def __str__(self): if not hasattr(self, '_class'): return object.__str__(self) if self._class is None: cls_name = "???" else: cls_name = self._class.full_name if self.return_value is None: retval = "retval?" else: retval = self.return_value.ctype if self.parameters is None: params = 'params?' else: params = ', '.join(["%s %s" % (param.ctype, param.name) for param in self.parameters]) return ("%s: %s %s::%s (%s);" % (self.visibility, retval, cls_name, cls_name, params)) class CppFunctionAsConstructor(CppConstructor): """ Class that generates a wrapper to a C/C++ function that appears as a contructor. """ def __init__(self, c_function_name, return_value, parameters, unblock_threads=None): """ :param c_function_name: name of the C/C++ function; FIXME: for now it is implied that this function returns a pointer to the a class instance with caller_owns_return=True semantics. :param return_value: function return value type :type return_value: L{ReturnValue} :param parameters: the function/constructor parameters :type parameters: list of L{Parameter} """ self.stack_where_defined = traceback.extract_stack() if unblock_threads is None: unblock_threads = settings.unblock_threads parameters = [utils.eval_param(param, self) for param in parameters] super(CppFunctionAsConstructor, self).__init__(parameters) self.c_function_name = c_function_name self.function_return_value = return_value def generate_call(self, class_=None): "virtual method implementation; do not call" if class_ is None: class_ = self._class #assert isinstance(class_, CppClass) assert class_.helper_class is None ## FIXME: check caller_owns_return in self.function_return_value self.before_call.write_code("self->obj = %s(%s);" % (self.c_function_name, ", ".join(self.call_params))) self.before_call.write_code("self->flags = PYBINDGEN_WRAPPER_FLAG_NONE;") class CppOverloadedConstructor(overloading.OverloadedWrapper): "Support class for overloaded constructors" RETURN_TYPE = 'int' ERROR_RETURN = 'return -1;' class CppNoConstructor(ForwardWrapperBase): """ Class that generates a constructor that raises an exception saying that the class has no constructor. """ def __init__(self, reason): """ :param reason: string indicating reason why the class cannot be constructed. """ self.stack_where_defined = traceback.extract_stack() super(CppNoConstructor, self).__init__( None, [], "return -1;", "return -1;") self.reason = reason def generate_call(self): "dummy method, not really called" pass def generate(self, code_sink, class_): """ Generates the wrapper code :param code_sink: a CodeSink instance that will receive the generated code :param class_: the c++ class wrapper the method belongs to Returns the wrapper function name. """ #assert isinstance(class_, CppClass) self.wrapper_actual_name = "_wrap_%s__tp_init" % ( class_.pystruct,) self.wrapper_return = 'static int' self.wrapper_args = ["void"] self.write_open_wrapper(code_sink) code_sink.writeln('PyErr_SetString(PyExc_TypeError, "class \'%s\' ' 'cannot be constructed (%s)");' % (class_.name, self.reason)) code_sink.writeln('return -1;') self.write_close_wrapper(code_sink) class CppVirtualMethodParentCaller(CppMethod): """ Class that generates a wrapper that calls a virtual method default implementation in a parent base class. """ def __init__(self, method, unblock_threads=None): super(CppVirtualMethodParentCaller, self).__init__( method.method_name, method.return_value, method.parameters, unblock_threads=unblock_threads) #self.static_decl = False self.method = method def get_class(self): return self.method.class_ class_ = property(get_class) #def set_class(self, class_): # "Set the class wrapper object (CppClass)" # self._class = class_ def generate_declaration(self, code_sink, extra_wrapper_parameters=()): ## We need to fake generate the code (and throw away the ## result) only in order to obtain correct method signature. self.reset_code_generation_state() self.generate(codesink.NullCodeSink(), extra_wrapper_params=extra_wrapper_parameters) assert isinstance(self.wrapper_return, str) assert isinstance(self.wrapper_actual_name, str) assert isinstance(self.wrapper_args, list) code_sink.writeln('%s %s(%s);' % (self.wrapper_return, self.wrapper_actual_name, ', '.join(self.wrapper_args))) self.reset_code_generation_state() def generate_class_declaration(self, code_sink, extra_wrapper_parameters=()): ## We need to fake generate the code (and throw away the ## result) only in order to obtain correct method signature. self.reset_code_generation_state() self.generate(codesink.NullCodeSink(), extra_wrapper_params=extra_wrapper_parameters) assert isinstance(self.wrapper_return, str) assert isinstance(self.wrapper_actual_name, str) assert isinstance(self.wrapper_args, list) dummy_cls, name = self.wrapper_actual_name.split('::') code_sink.writeln('static %s %s(%s);' % (self.wrapper_return, name, ', '.join(self.wrapper_args))) self.reset_code_generation_state() def generate_parent_caller_method(self, code_sink): ## generate a '%s__parent_caller' method (static methods ## cannot "conquer" 'protected' access type, only regular ## instance methods). code_sink.writeln('inline %s %s__parent_caller(%s)' % ( self.return_value.ctype, self.method_name, ', '.join([join_ctype_and_name(param.ctype, param.name) for param in self.parameters]) )) if self.return_value.ctype == 'void': code_sink.writeln('{ %s::%s(%s); }' % (self.method.class_.full_name, self.method_name, ', '.join([param.name for param in self.parameters]))) else: code_sink.writeln('{ return %s::%s(%s); }' % (self.method.class_.full_name, self.method_name, ', '.join([param.name for param in self.parameters]))) def generate_call(self, class_=None): "virtual method implementation; do not call" class_ = self.class_ helper = self.before_call.declare_variable( type_=('%s*' % self._helper_class.name), name='helper', initializer=("dynamic_cast< %s* >(self->obj)" % self._helper_class.name)) method = '%s->%s__parent_caller' % (helper, self.method_name) self.before_call.write_error_check( "%s == NULL" % helper, 'PyErr_SetString(PyExc_TypeError, "Method %s of class %s is protected and can only be called by a subclass");' % (self.method_name, self.class_.name)) if self.return_value.ctype == 'void': self.before_call.write_code( '%s(%s);' % (method, ", ".join(self.call_params))) else: if self.return_value.REQUIRES_ASSIGNMENT_CONSTRUCTOR: self.before_call.write_code( '%s retval = %s(%s);' % (self.return_value.ctype, method, ", ".join(self.call_params))) else: self.before_call.write_code( 'retval = %s(%s);' % (method, ", ".join(self.call_params))) def get_py_method_def(self, method_name=None): "Get the PyMethodDef entry suitable for this method" assert self.wrapper_actual_name == self.wrapper_base_name, \ "wrapper_actual_name=%r but wrapper_base_name=%r" % \ (self.wrapper_actual_name, self.wrapper_base_name) assert self._helper_class is not None if method_name is None: method_name = self.method_name flags = self.get_py_method_def_flags() return "{(char *) \"%s\", (PyCFunction) %s, %s, %s }," % \ (method_name, self.wrapper_actual_name,#'::'.join((self._helper_class.name, self.wrapper_actual_name)), '|'.join(flags), (self.docstring is None and "NULL" or ('"'+self.docstring+'"'))) def clone(self): """ Creates a semi-deep copy of this method wrapper. The returned method wrapper clone contains copies of all parameters, so they can be modified at will. """ meth = CppVirtualMethodParentCaller( self.return_value, self.method_name, [copy(param) for param in self.parameters]) #meth._class = self._class meth.method = self.method meth._helper_class = self._helper_class meth.docstring = self.docstring meth.wrapper_base_name = self.wrapper_base_name meth.wrapper_actual_name = self.wrapper_actual_name return meth class CppVirtualMethodProxy(ReverseWrapperBase): """ Class that generates a proxy virtual method that calls a similarly named python method. """ def __init__(self, method): self.stack_where_defined = traceback.extract_stack() super(CppVirtualMethodProxy, self).__init__(method.return_value, method.parameters) self.method_name = method.method_name self.method = method self._helper_class = None def get_class(self): "Get the class wrapper object (CppClass)" return self.method.class_ class_ = property(get_class) def set_helper_class(self, helper_class): "Set the C++ helper class, which is used for overriding virtual methods" self._helper_class = helper_class self.wrapper_base_name = "_wrap_%s" % self.method_name def get_helper_class(self): "Get the C++ helper class, which is used for overriding virtual methods" return self._helper_class helper_class = property(get_helper_class, set_helper_class) def generate_python_call(self): """code to call the python method""" if settings._get_deprecated_virtuals(): params = ['m_pyself', '(char *) "_%s"' % self.method_name] else: params = ['m_pyself', '(char *) "%s"' % self.method_name] build_params = self.build_params.get_parameters() if build_params[0][0] == '"': build_params[0] = '(char *) ' + build_params[0] params.extend(build_params) self.before_call.write_code('py_retval = PyObject_CallMethod(%s);' % (', '.join(params),)) self.before_call.write_error_check('py_retval == NULL', failure_cleanup='PyErr_Print();') self.before_call.add_cleanup_code('Py_DECREF(py_retval);') def generate_declaration(self, code_sink): if self.method.is_const: decl_post_modifiers = ' const' else: decl_post_modifiers = '' if self.method.throw: decl_post_modifiers += " throw (%s)" % (', '.join([ex.full_name for ex in self.method.throw]),) params_list = ', '.join([join_ctype_and_name(param.ctype, param.name) for param in self.parameters]) code_sink.writeln("virtual %s %s(%s)%s;" % (self.return_value.ctype, self.method_name, params_list, decl_post_modifiers)) def generate(self, code_sink): """generates the proxy virtual method""" if self.method.is_const: decl_post_modifiers = ['const'] else: decl_post_modifiers = [] if self.method.throw: decl_post_modifiers.append("throw (%s)" % (', '.join([ex.full_name for ex in self.method.throw]),)) ## if the python subclass doesn't define a virtual method, ## just chain to parent class and don't do anything else call_params = ', '.join([param.name for param in self.parameters]) py_method = self.declarations.declare_variable('PyObject*', 'py_method') if settings._get_deprecated_virtuals(): self.before_call.write_code('%s = PyObject_GetAttrString(m_pyself, (char *) "_%s"); PyErr_Clear();' % (py_method, self.method_name)) else: self.before_call.write_code('%s = PyObject_GetAttrString(m_pyself, (char *) "%s"); PyErr_Clear();' % (py_method, self.method_name)) self.before_call.add_cleanup_code('Py_XDECREF(%s);' % py_method) self.before_call.write_code( r'if (%s == NULL || %s->ob_type == &PyCFunction_Type) {' % (py_method, py_method)) if self.return_value.ctype == 'void': if not (self.method.is_pure_virtual or self.method.visibility == 'private'): self.before_call.write_code(r' %s::%s(%s);' % (self.class_.full_name, self.method_name, call_params)) self.before_call.write_cleanup() self.before_call.write_code(r' return;') else: if self.method.is_pure_virtual or self.method.visibility == 'private': if isinstance(self.return_value, cppclass.CppClassReturnValue) \ and self.return_value.cpp_class.has_trivial_constructor: pass else: self.set_error_return(''' PyErr_Print(); Py_FatalError("Error detected, but parent virtual is pure virtual or private virtual, " "and return is a class without trival constructor");''') else: self.set_error_return("return %s::%s(%s);" % (self.class_.full_name, self.method_name, call_params)) self.before_call.indent() self.before_call.write_cleanup() self.before_call.write_code(self.error_return) self.before_call.unindent() self.before_call.write_code('}') ## Set "m_pyself->obj = this" around virtual method call invocation self_obj_before = self.declarations.declare_variable( '%s*' % self.class_.full_name, 'self_obj_before') self.before_call.write_code("%s = reinterpret_cast< %s* >(m_pyself)->obj;" % (self_obj_before, self.class_.pystruct)) if self.method.is_const: this_expression = ("const_cast< %s* >((const %s*) this)" % (self.class_.full_name, self.class_.full_name)) else: this_expression = "(%s*) this" % (self.class_.full_name) self.before_call.write_code("reinterpret_cast< %s* >(m_pyself)->obj = %s;" % (self.class_.pystruct, this_expression)) self.before_call.add_cleanup_code("reinterpret_cast< %s* >(m_pyself)->obj = %s;" % (self.class_.pystruct, self_obj_before)) super(CppVirtualMethodProxy, self).generate( code_sink, '::'.join((self._helper_class.name, self.method_name)), decl_modifiers=[], decl_post_modifiers=decl_post_modifiers) def __str__(self): return str(self.method) class CustomCppMethodWrapper(CppMethod): """ Adds a custom method wrapper. The custom wrapper must be prepared to support overloading, i.e. it must have an additional "PyObject \\*\\*return_exception" parameter, and raised exceptions must be returned by this parameter. """ NEEDS_OVERLOADING_INTERFACE = True def __init__(self, method_name, wrapper_name, wrapper_body=None, flags=('METH_VARARGS', 'METH_KEYWORDS')): super(CustomCppMethodWrapper, self).__init__(method_name, ReturnValue.new('void'), []) self.wrapper_base_name = wrapper_name self.wrapper_actual_name = wrapper_name self.meth_flags = list(flags) self.wrapper_body = wrapper_body def generate(self, code_sink, dummy_wrapper_name=None, extra_wrapper_params=()): assert extra_wrapper_params == ["PyObject **return_exception"] self.wrapper_args = ["%s *self" % self.class_.pystruct, "PyObject *args", "PyObject *kwargs", "PyObject **return_exception"] self.wrapper_return = "PyObject *" if self.wrapper_body is not None: code_sink.writeln(self.wrapper_body) else: self.generate_declaration(code_sink, extra_wrapper_parameters=extra_wrapper_params) def generate_declaration(self, code_sink, extra_wrapper_parameters=()): assert isinstance(self.wrapper_return, str) assert isinstance(self.wrapper_actual_name, str) assert isinstance(self.wrapper_args, list) code_sink.writeln('%s %s(%s);' % (self.wrapper_return, self.wrapper_actual_name, ', '.join(self.wrapper_args))) def generate_call(self, *args, **kwargs): pass class CustomCppConstructorWrapper(CppConstructor): """ Adds a custom constructor wrapper. The custom wrapper must be prepared to support overloading, i.e. it must have an additional \\"PyObject \\*\\*return_exception\\" parameter, and raised exceptions must be returned by this parameter. """ NEEDS_OVERLOADING_INTERFACE = True def __init__(self, wrapper_name, wrapper_body): super(CustomCppConstructorWrapper, self).__init__([]) self.wrapper_base_name = wrapper_name self.wrapper_actual_name = wrapper_name self.wrapper_body = wrapper_body def generate(self, code_sink, dummy_wrapper_name=None, extra_wrapper_params=()): assert extra_wrapper_params == ["PyObject **return_exception"] code_sink.writeln(self.wrapper_body) return ("int %s (%s *self, PyObject *args, PyObject *kwargs, PyObject **return_exception)" % (self.wrapper_actual_name, self.class_.pystruct)) def generate_call(self, *args, **kwargs): pass import cppclass import cppclass_typehandlers