[mojo] Add Mojo bindings support for IPC::ParamTraits

mojo/public/tools/bindings/generators/mojom_cpp_generator.py

Index: mojo/public/tools/bindings/generators/mojom_cpp_generator.py
diff --git a/mojo/public/tools/bindings/generators/mojom_cpp_generator.py b/mojo/public/tools/bindings/generators/mojom_cpp_generator.py
index f5219a3a3e1cf07e5b20428dabad720fff4cc4b7..6b2322eaf54b64544701bb682f243caba16a92dd 100644
--- a/mojo/public/tools/bindings/generators/mojom_cpp_generator.py
+++ b/mojo/public/tools/bindings/generators/mojom_cpp_generator.py
@@ -42,9 +42,25 @@ _kind_to_cpp_literal_suffix = {
   mojom.UINT64:       "ULL",
 }
 
+
 _current_variant = None
 
 
+_variant_metadata_attributes = {
+  "chromium": {
+    "typename": "ChromiumType",
+    "headers": "ChromiumHeaders",
+  },
+  "blink": {
+    "typename": "BlinkType",
+    "headers": "BlinkHeaders",
+  }
+}
+
+
+_variant_typemap = {}
+
+
 def ConstantValue(constant):
   return ExpressionToText(constant.value, kind=constant.kind)
 
@@ -56,6 +72,13 @@ def DefaultValue(field):
     return ExpressionToText(field.default, kind=field.kind)
   return ""
 
+def IsNativeKind(kind):
+  if hasattr(kind, "name") and kind.name in _variant_typemap:
+    return True
+
+def GetNativeTypeName(kind):
+  return _variant_typemap[kind.name]
+
 def NamespaceToArray(namespace):
   return namespace.split(".") if namespace else []
 
@@ -72,6 +95,11 @@ def GetNameForKind(kind, internal = False):
   parts.append(kind.name)
   return "::".join(parts)
 
+def GetQualifiedGenericInterfaceName(interface_kind):
+  parts = NamespaceToArray(interface_kind.module.namespace)
+  parts.append(interface_kind.name)
+  return "::".join(parts)
+
 def GetCppType(kind):
   if mojom.IsArrayKind(kind):
     return "mojo::internal::Array_Data<%s>*" % GetCppType(kind.kind)
@@ -135,6 +163,8 @@ def GetCppArrayArgWrapperType(kind):
   return _kind_to_cpp_type[kind]
 
 def GetCppResultWrapperType(kind):
+  if IsNativeKind(kind):
+    return "const %s&" % GetNativeTypeName(kind)
   if mojom.IsEnumKind(kind):
     return GetNameForKind(kind)
   if mojom.IsStructKind(kind) or mojom.IsUnionKind(kind):
@@ -173,6 +203,8 @@ def GetCppResultWrapperType(kind):
   raise Exception("Unrecognized kind %s" % kind.spec)
 
 def GetCppWrapperType(kind):
+  if IsNativeKind(kind):
+    return GetNativeTypeName(kind)
   if mojom.IsEnumKind(kind):
     return GetNameForKind(kind)
   if mojom.IsStructKind(kind) or mojom.IsUnionKind(kind):
@@ -205,6 +237,8 @@ def GetCppWrapperType(kind):
   return _kind_to_cpp_type.get(kind)
 
 def GetCppConstWrapperType(kind):
+  if IsNativeKind(kind):
+    return "const %s&" % GetNativeTypeName(kind)
   if mojom.IsStructKind(kind) or mojom.IsUnionKind(kind):
     return "%sPtr" % GetNameForKind(kind)
   if mojom.IsArrayKind(kind):
@@ -239,6 +273,8 @@ def GetCppConstWrapperType(kind):
   return _kind_to_cpp_type[kind]
 
 def GetCppFieldType(kind):
+  if IsNativeKind(kind):
+    return "mojo::internal::NativePointer<%s>" % GetNativeTypeName(kind)
   if mojom.IsStructKind(kind):
     return ("mojo::internal::StructPointer<%s_Data>" %
         GetNameForKind(kind, internal=True))
@@ -397,6 +433,7 @@ class Generator(generator.Generator):
     "get_map_validate_params_ctor_args": GetMapValidateParamsCtorArgs,
     "get_name_for_kind": GetNameForKind,
     "get_pad": pack.GetPad,
+    "get_qualified_generic_interface_name": GetQualifiedGenericInterfaceName,
     "has_callbacks": mojom.HasCallbacks,
     "should_inline": ShouldInlineStruct,
     "should_inline_union": ShouldInlineUnion,
@@ -405,6 +442,7 @@ class Generator(generator.Generator):
     "is_enum_kind": mojom.IsEnumKind,
     "is_integral_kind": mojom.IsIntegralKind,
     "is_move_only_kind": mojom.IsMoveOnlyKind,
+    "is_native_kind": IsNativeKind,
     "is_any_handle_kind": mojom.IsAnyHandleKind,
     "is_interface_kind": mojom.IsInterfaceKind,
     "is_interface_request_kind": mojom.IsInterfaceRequestKind,
@@ -428,7 +466,30 @@ class Generator(generator.Generator):
   chromium_cpp_filters = dict(cpp_filters)
   blink_cpp_filters = dict(cpp_filters)
 
+  def GetExtraHeaders(self):
+    if not _current_variant:
+      return []
+    extra_headers = []
+    headers_attribute = \
+        _variant_metadata_attributes[_current_variant]["headers"]
+    for struct in self.GetStructs():
+      if struct.attributes:
+        headers = struct.attributes.get(headers_attribute, [])
+        extra_headers.extend(headers)
+    return extra_headers
+
   def GetJinjaExports(self):
+    global _variant_typemap
+    _variant_typemap = {}
+    if _current_variant:
+      typename_attribute = \
+          _variant_metadata_attributes[_current_variant]["typename"]
+      for struct in self.GetStructs():
+        if struct.attributes:
+          typename = struct.attributes.get(typename_attribute)
+          if typename:
+            _variant_typemap[struct.name] = typename
+
     return {
       "module": self.module,
       "namespace": self.module.namespace,
@@ -440,6 +501,7 @@ class Generator(generator.Generator):
       "unions": self.GetUnions(),
       "interfaces": self.GetInterfaces(),
       "variant": _current_variant,
+      "extra_headers": self.GetExtraHeaders(),
     }
 
   @UseJinja("cpp_templates/module.h.tmpl", filters=cpp_filters)