WTF NPAPI extension. Early draft.

tools/nixysa/nixysa/nullable_binding.py

Index: tools/nixysa/nixysa/nullable_binding.py
===================================================================
--- tools/nixysa/nixysa/nullable_binding.py	(revision 0)
+++ tools/nixysa/nixysa/nullable_binding.py	(revision 0)
@@ -0,0 +1,533 @@
+#!/usr/bin/python2.4
+#
+# Copyright 2008 Google Inc.
+#
+# 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.
+
+"""nullable binding model module.
+
+This module implements the glue functions for the nullable binding model,
+used for nullable types.
+
+In C++, objects using this binding model are represented by a pointer.
+For JS bindings, the nullable type is represented by a JavaScript reference.
+"""
+
+import by_pointer_binding
+import string
+
+
+class InvalidNullableUsage(Exception):
+  """Raised when a nullable is used in conjuction with a type that is not a
+  pointer pointer binding."""
+  pass
+
+
+def JavaMemberString(scope, type_defn):
+  """Gets the representation of a member name in Java.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition for the type.
+
+  Returns:
+    a string representing the type
+  """
+  data_type = type_defn.GetFinalType().data_type
+  data_type_bm = data_type.binding_model
+  return data_type_bm.JavaMemberString(scope, data_type)
+
+
+def CppTypedefString(scope, type_defn):
+  """Gets the representation of a type when used in a C++ typedef.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition for the type.
+
+  Returns:
+    a (string, boolean) pair, the first element being the representation of
+    the type, the second element indicating whether or not the definition of
+    the type is needed for the expression to be valid.
+  """
+  data_type = type_defn.GetFinalType().data_type
+  data_type_bm = data_type.binding_model
+  return data_type_bm.CppTypedefString(scope, data_type)
+
+
+def CppMemberString(scope, type_defn):
+  """Gets the representation of a type when used as a C++ class member.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition for the type.
+
+  Returns:
+    a (string, boolean) pair, the first element being the representation of
+    the type, the second element indicating whether or not the definition of
+    the type is needed for the expression to be valid.
+  """
+  data_type = type_defn.GetFinalType().data_type
+  data_type_bm = data_type.binding_model
+  return data_type_bm.CppMemberString(scope, data_type)
+
+
+def CppReturnValueString(scope, type_defn):
+  """Gets the representation of a type when used as a C++ function return value.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition for the type.
+
+  Returns:
+    a (string, boolean) pair, the first element being the representation of
+    the type, the second element indicating whether or not the definition of
+    the type is needed for the expression to be valid.
+  """
+  data_type = type_defn.GetFinalType().data_type
+  data_type_bm = data_type.binding_model
+  return data_type_bm.CppReturnValueString(scope, data_type)
+
+
+def CppParameterString(scope, type_defn):
+  """Gets the representation of a type when used for a function parameter.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition for the type.
+
+  Returns:
+    a (string, boolean) pair, the first element being the representation of
+    the type, the second element indicating whether or not the definition of
+    the type is needed for the expression to be valid.
+  """
+  data_type = type_defn.GetFinalType().data_type
+  data_type_bm = data_type.binding_model
+  return data_type_bm.CppParameterString(scope, data_type)
+
+
+def CppMutableParameterString(scope, type_defn):
+  """Gets the representation of a type for a mutable function parameter.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition for the type.
+
+  Returns:
+    a (string, boolean) pair, the first element being the string representing
+    the type, the second element indicating whether or not the definition of
+    the type is needed for the expression to be valid.
+  """
+  data_type = type_defn.GetFinalType().data_type
+  data_type_bm = data_type.binding_model
+  return data_type_bm.CppMutableParameterString(scope, data_type)
+
+
+def CppMutableToNonMutable(scope, type_defn, expr):
+  """Gets the string converting a mutable expression to a non-mutable one.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition for the type.
+    expr: a string for the mutable expression.
+
+  Returns:
+    a string, which is the non-mutable expression.
+  """
+  data_type = type_defn.GetFinalType().data_type
+  data_type_bm = data_type.binding_model
+  return data_type_bm.CppMutableToNonMutable(scope, data_type, expr)
+
+
+def CppBaseClassString(scope, type_defn):
+  """Gets the representation of a type for a base class.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition for the type.
+
+  Returns:
+    a (string, boolean) pair, the first element being the string representing
+    the type, the second element indicating whether or not the definition of
+    the type is needed for the expression to be valid.
+
+  Raises:
+    InvalidNullableUsage: always. This function should not be called on a
+      nullable.
+  """
+  raise InvalidNullableUsage
+
+
+def CppCallMethod(scope, type_defn, object_expr, mutable, method, param_exprs):
+  """Gets the representation of a member function call.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition, representing the type of the object being called.
+    object_expr: a string, which is the expression for the object being called.
+    mutable: a boolean, whether or not the 'object_expr' expression is mutable
+      or not
+    method: a Function, representing the function to call.
+    param_exprs: a list of strings, each being the expression for the value of
+      each parameter.
+
+  Returns:
+    a string, which is the expression for the function call.
+
+  Raises:
+    InvalidNullableUsage: always. This function should not be called on a
+      nullable.
+  """
+  return InvalidNullableUsage
+
+
+def CppCallStaticMethod(scope, type_defn, method, param_exprs):
+  """Gets the representation of a static function call.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition, representing the type of the object being called.
+    method: a Function, representing the function to call.
+    param_exprs: a list of strings, each being the expression for the value of
+      each parameter.
+
+  Returns:
+    a string, which is the expression for the function call.
+
+  Raises:
+    InvalidNullableUsage: always. This function should not be called on a
+      nullable.
+  """
+  return InvalidNullableUsage
+
+
+def CppCallConstructor(scope, type_defn, method, param_exprs):
+  """Gets the representation of a constructor call.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition, representing the type of the object being called.
+    method: a Function, representing the constructor to call.
+    param_exprs: a list of strings, each being the expression for the value of
+      each parameter.
+
+  Returns:
+    a string, which is the expression for the constructor call.
+
+  Raises:
+    InvalidNullableUsage: always. This function should not be called on a
+      nullable.
+  """
+  return InvalidNullableUsage
+
+
+def CppSetField(scope, type_defn, object_expr, field, param_expr):
+  """Gets the representation of an expression setting a field in an object.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition, representing the type of the object containing the
+      field being set.
+    object_expr: a string, which is the expression for the object containing
+      the field being set.
+    field: a string, the name of the field to be set.
+    param_expr: a strings, being the expression for the value to be set.
+
+  Returns:
+    a string, which is the expression for setting the field.
+
+  Raises:
+    InvalidNullableUsage: always. This function should not be called on a
+      nullable.
+  """
+  return InvalidNullableUsage
+
+
+def CppGetField(scope, type_defn, object_expr, field):
+  """Gets the representation of an expression getting a field in an object.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition, representing the type of the object containing the
+      field being retrieved.
+    object_expr: a string, which is the expression for the object containing
+      the field being retrieved.
+    field: a string, the name of the field to be retrieved.
+
+  Returns:
+    a string, which is the expression for getting the field.
+
+  Raises:
+    InvalidNullableUsage: always. This function should not be called on a
+      nullable.
+  """
+  return InvalidNullableUsage
+
+
+def CppSetStatic(scope, type_defn, field, param_expr):
+  """Gets the representation of an expression setting a static field.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition, representing the type of the object containing the
+      field being set.
+    field: a string, the name of the field to be set.
+    param_expr: a strings, being the expression for the value to be set.
+
+  Returns:
+    a string, which is the expression for setting the field.
+
+  Raises:
+    InvalidNullableUsage: always. This function should not be called on a
+      nullable.
+  """
+  return InvalidNullableUsage
+
+
+def CppGetStatic(scope, type_defn, field):
+  """Gets the representation of an expression getting a static field.
+
+  Args:
+    scope: a Definition for the scope in which the expression will be written.
+    type_defn: a Definition, representing the type of the object containing the
+      field being retrieved.
+    field: a string, the name of the field to be retrieved.
+
+  Returns:
+    a string, which is the expression for getting the field.
+
+  Raises:
+    InvalidNullableUsage: always. This function should not be called on a
+      nullable.
+  """
+  return InvalidNullableUsage
+
+
+def JSDocTypeString(type_defn):
+  """Gets the representation of a type in JSDoc notation.
+
+  Args:
+    type_defn: a Definition for the type.
+
+  Returns:
+    a string that is the JSDoc notation of type_defn.
+  """
+  type_defn = type_defn.GetFinalType()
+  element_type_defn = type_defn.data_type.GetFinalType()
+  type = element_type_defn.binding_model.JSDocTypeString(element_type_defn)
+  if type[0] == '!':
+    type = type[1:]
+  return type
+
+
+def NpapiBindingGlueHeader(scope, type_defn):
+  """Gets the NPAPI glue header for a given type.
+
+  Args:
+    scope: a Definition for the scope in which the glue will be written.
+    type_defn: a Definition, representing the type.
+
+  Returns:
+    a string, the glue header.
+
+  Raises:
+    InvalidNullableUsage: always. This function should not be called on a
+      nullable.
+  """
+  return InvalidNullableUsage
+
+
+def NpapiBindingGlueCpp(scope, type_defn):
+  """Gets the NPAPI glue implementation for a given type.
+
+  Args:
+    scope: a Definition for the scope in which the glue will be written.
+    type_defn: a Definition, representing the type.
+
+  Returns:
+    a string, the glue implementation.
+
+  Raises:
+    InvalidNullableUsage: always. This function should not be called on a
+      nullable.
+  """
+  return InvalidNullableUsage
+
+
+def NpapiDispatchFunctionHeader(scope, type_defn, variable, npp, success):
+  """Gets a header for NPAPI glue dispatch functions.
+
+  This function creates a string containing a C++ code snippet that should be
+  included at the beginning of NPAPI glue dispatch functions like Invoke or
+  GetProperty. This code snippet will declare and initialize certain variables
+  that will be used in the dispatch functions, like the NPObject representing
+  the object, or a pointer to the NPP instance.
+
+  First it checks whether the NPVariant is null. If so it simply sets the value
+  to null. It relies on the later compilation of the glue to detect when it is
+  used with a binding model that cannot be used with nthe value null. It is
+  binding model independent.
+
+  Args:
+    scope: a Definition for the scope in which the glue will be written.
+    type_defn: a Definition, representing the type.
+    variable: a string, representing a name of a variable that can be used to
+      store a reference to the object.
+    npp: a string, representing the name of the variable that holds the pointer
+      to the NPP instance. Will be declared by the code snippet.
+    success: the name of a bool variable containing the current success status.
+      (is not declared by the code snippet).
+
+  Returns:
+    a (string, string) pair, the first string being the code snippet, and the
+    second string being an expression to access the object.
+
+  Raises:
+    InvalidNullableUsage: always. This function should not be called on a
+      nullable.
+  """
+  return InvalidNullableUsage
+
+_from_npvariant_template = string.Template("""
+${Type} ${variable};
+if (NPVARIANT_IS_NULL(${input})) {
+  ${variable} = NULL;
+} else {
+  ${text}
+  ${variable} = ${value};
+}
+""")
+
+
+def NpapiFromNPVariant(scope, type_defn, input_expr, variable, success,
+    exception_context, npp):
+  """Gets the string to get a value from a NPVariant.
+
+  This function creates a string containing a C++ code snippet that is used to
+  retrieve a value from a NPVariant. If an error occurs, like if the NPVariant
+  is not of the correct type, the snippet will set the success status variable
+  to false.
+
+  Args:
+    scope: a Definition for the scope in which the glue will be written.
+    type_defn: a Definition, representing the type of the value.
+    input_expr: an expression representing the NPVariant to get the value from.
+    variable: a string, representing a name of a variable that can be used to
+      store a reference to the value.
+    success: the name of a bool variable containing the current success status.
+    exception_context: the name of a string containing context information, for
+      use in exception reporting.
+    npp: a string, representing the name of the variable that holds the pointer
+      to the NPP instance.
+
+  Returns:
+    a (string, string) pair, the first string being the code snippet and the
+    second one being the expression to access that value.
+  """
+  data_type = type_defn.GetFinalType().data_type
+  data_type_bm = data_type.binding_model
+  text, value = data_type_bm.NpapiFromNPVariant(
+      scope,
+      data_type,
+      input_expr,
+      variable + '_nullable',
+      success,
+      exception_context,
+      npp);
+
+  data_type_name, dummy = data_type_bm.CppMemberString(scope, data_type)
+  nullable_text = _from_npvariant_template.substitute(
+      Type=data_type_name,
+      variable=variable,
+      text=text,
+      input=input_expr,
+      value=value)
+
+  return (nullable_text, variable)
+
+
+_to_npvariant_pre_template = string.Template("""
+${pre_text}
+if (!${variable}) {
+  success = true;
+}
+""")
+
+
+_to_npvariant_post_template = string.Template("""
+if (${variable}) {
+  ${post_text}
+} else {
+  NULL_TO_NPVARIANT(*${output});
+}
+""")
+
+
+def NpapiExprToNPVariant(scope, type_defn, variable, expression, output,
+                         success, npp):
+  """Gets the string to store a value into a NPVariant.
+
+  This function creates a string containing a C++ code snippet that is used to
+  store a value into a NPVariant. That operation takes two phases, one that
+  allocates necessary NPAPI resources, and that can fail, and one that actually
+  sets the NPVariant (that can't fail). If an error occurs, the snippet will
+  set the success status variable to false.
+
+  Args:
+    scope: a Definition for the scope in which the glue will be written.
+    type_defn: a Definition, representing the type of the value.
+    variable: a string, representing a name of a variable that can be used to
+      store a reference to the value.
+    expression: a string representing the expression that yields the value to
+      be stored.
+    output: an expression representing a pointer to the NPVariant to store the
+      value into.
+    success: the name of a bool variable containing the current success status.
+    npp: a string, representing the name of the variable that holds the pointer
+      to the NPP instance.
+
+  Returns:
+    a (string, string) pair, the first string being the code snippet for the
+    first phase, and the second one being the code snippet for the second phase.
+  """
+  data_type = type_defn.GetFinalType().data_type
+  data_type_bm = data_type.binding_model
+  pre_text, post_text = data_type_bm.NpapiExprToNPVariant(
+      scope,
+      data_type,
+      variable,
+      expression,
+      output,
+      success,
+      npp)
+
+  nullable_pre_text = _to_npvariant_pre_template.substitute(
+      variable=variable,
+      npp=npp,
+      pre_text=pre_text,
+      success=success)
+
+  nullable_post_text = _to_npvariant_post_template.substitute(
+      variable=variable,
+      output=output,
+      npp=npp,
+      post_text=post_text,
+      success=success)
+
+  return nullable_pre_text, nullable_post_text
+
+def main():
+  pass
+
+if __name__ == '__main__':
+  main()
Property changes on: tools/nixysa/nixysa/nullable_binding.py
___________________________________________________________________
Added: svn:eol-style
   + LF