diff -r 000000000000 -r 6474c204b198 js/xpconnect/src/event_impl_gen.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/xpconnect/src/event_impl_gen.py	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,744 @@
+#!/usr/bin/env python
+# header.py - Generate C++ header files from IDL.
+#
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import sys, os, xpidl, makeutils
+
+def strip_end(text, suffix):
+    if not text.endswith(suffix):
+        return text
+    return text[:-len(suffix)]
+
+def findIDL(includePath, interfaceFileName):
+    for d in includePath:
+        # Not os.path.join: we need a forward slash even on Windows because
+        # this filename ends up in makedepend output.
+        path = d + '/' + interfaceFileName
+        if os.path.exists(path):
+            return path
+    raise BaseException("No IDL file found for interface %s "
+                        "in include path %r"
+                        % (interfaceFileName, includePath))
+
+eventFileNameToIdl = {};
+
+def loadIDL(parser, includePath, filename):
+    global eventFileNameToIdl
+    if filename in eventFileNameToIdl:
+        return eventFileNameToIdl[filename]
+
+    idlFile = findIDL(includePath, filename)
+    if not idlFile in makeutils.dependencies:
+        makeutils.dependencies.append(idlFile)
+    idl = p.parse(open(idlFile).read(), idlFile)
+    idl.resolve(includePath, p)
+    eventFileNameToIdl[filename] = idl
+    return idl
+
+def loadEventIDL(parser, includePath, eventname):
+    eventidl = ("nsIDOM%s.idl" % eventname)
+    return loadIDL(parser, includePath, eventidl)
+
+class Configuration:
+    def __init__(self, filename):
+        config = {}
+        execfile(filename, config)
+        self.simple_events = config.get('simple_events', [])
+        self.special_includes = config.get('special_includes', [])
+        self.exclude_automatic_type_include = config.get('exclude_automatic_type_include', [])
+        self.xpidl_to_native = config.get('xpidl_to_native', [])
+
+def readConfigFile(filename):
+    return Configuration(filename)
+
+def firstCap(str):
+    return str[0].upper() + str[1:]
+
+def getBaseName(iface):
+    return ("%s" % iface.base[6:])
+
+def print_header_file(fd, conf):
+    fd.write("#ifndef _gen_mozilla_idl_generated_events_h_\n"
+             "#define _gen_mozilla_idl_generated_events_h_\n\n")
+    fd.write("/* THIS FILE IS AUTOGENERATED - DO NOT EDIT */\n")
+    fd.write("#include \"nscore.h\"\n")
+    fd.write("class nsIDOMEvent;\n")
+    fd.write("class nsPresContext;\n")
+    fd.write("namespace mozilla {\n");
+    fd.write("class WidgetEvent;\n")
+    fd.write("namespace dom {\n");
+    fd.write("class EventTarget;\n")
+    fd.write("}\n");
+    fd.write("}\n\n");
+    for e in conf.simple_events:
+        fd.write("nsresult\n")
+        fd.write("NS_NewDOM%s(nsIDOMEvent** aInstance, " % e)
+        fd.write("mozilla::dom::EventTarget* aOwner, ")
+        fd.write("nsPresContext* aPresContext, mozilla::WidgetEvent* aEvent);\n")
+
+    fd.write("\n#endif\n")
+
+def print_classes_file(fd, conf):
+    fd.write("#ifndef _gen_mozilla_idl_generated_event_declarations_h_\n")
+    fd.write("#define _gen_mozilla_idl_generated_event_declarations_h_\n\n")
+
+    fd.write("#include \"mozilla/dom/Event.h\"\n");
+    includes = []
+    for s in conf.special_includes:
+        if not s in includes:
+            includes.append(strip_end(s, ".h"))
+
+    for e in conf.simple_events:
+        if not e in includes:
+            includes.append(("nsIDOM%s" % e))
+
+    attrnames = []
+    for e in conf.simple_events:
+        idl = loadEventIDL(p, options.incdirs, e)
+        collect_names_and_non_primitive_attribute_types(idl, attrnames, includes)
+
+    for c in includes:
+      if not c in conf.exclude_automatic_type_include:
+            fd.write("#include \"%s.h\"\n" % c)
+
+    for e in conf.simple_events:
+        fd.write('#include "mozilla/dom/%sBinding.h"\n' % e);
+
+    fd.write("namespace mozilla {\n")
+    fd.write("namespace dom {\n")
+    for e in conf.simple_events:
+        idl = loadEventIDL(p, options.incdirs, e)
+        for pr in idl.productions:
+            if pr.kind == 'interface':
+                print_class_declaration(e, pr, fd, conf)
+    fd.write("} // namespace dom\n")
+    fd.write("} // namespace mozilla\n\n")
+    fd.write("#endif\n");
+
+def print_class_declaration(eventname, iface, fd, conf):
+    classname = ("%s" % eventname)
+    basename = getBaseName(iface)
+    attributes = []
+    ccattributes = []
+    for member in iface.members:
+        if isinstance(member, xpidl.Attribute):
+            attributes.append(member)
+            if (member.realtype.nativeType('in').endswith('*')):
+                ccattributes.append(member);
+
+    baseinterfaces = []
+    baseiface = iface.idl.getName(iface.base, iface.location)
+    while baseiface.name != "nsIDOMEvent":
+        baseinterfaces.append(baseiface)
+        baseiface = baseiface.idl.getName(baseiface.base, baseiface.location)
+    baseinterfaces.reverse()
+
+    allattributes = []
+    for baseiface in baseinterfaces:
+        for member in baseiface.members:
+            if isinstance(member, xpidl.Attribute):
+                allattributes.append(member)
+    allattributes.extend(attributes);
+
+    fd.write("\nclass %s MOZ_FINAL : public %s, public %s\n" % (classname, basename, iface.name))
+    fd.write("{\n")
+    fd.write("public:\n")
+    fd.write("  %s(mozilla::dom::EventTarget* aOwner, " % classname)
+    fd.write("nsPresContext* aPresContext = nullptr, mozilla::WidgetEvent* aEvent = nullptr);\n");
+    fd.write("  virtual ~%s();\n\n" % classname)
+    fd.write("  NS_DECL_ISUPPORTS_INHERITED\n")
+    fd.write("  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(%s, %s)\n" % (classname, basename))
+    fd.write("  NS_FORWARD_TO_EVENT\n")
+
+    for baseiface in baseinterfaces:
+        baseimpl = ("%s" % baseiface.name[6:])
+        fd.write("  NS_FORWARD_%s(%s::)\n" % (baseiface.name.upper(), baseimpl))
+
+    fd.write("  NS_DECL_%s\n" % iface.name.upper())
+
+    hasVariant = False
+    for a in allattributes:
+        if a.type == "nsIVariant":
+            hasVariant = True
+            break;
+    fd.write("  static already_AddRefed<%s> Constructor(const GlobalObject& aGlobal, " % eventname)
+    if hasVariant:
+        fd.write("JSContext* aCx, ")
+    fd.write("const nsAString& aType, ")
+    fd.write("const %sInit& aParam, " % eventname)
+    fd.write("ErrorResult& aRv);\n\n")
+
+    fd.write("  virtual JSObject* WrapObject(JSContext* aCx) MOZ_OVERRIDE\n")
+    fd.write("  {\n")
+    fd.write("    return mozilla::dom::%sBinding::Wrap(aCx, this);\n" % eventname)
+    fd.write("  }\n\n")
+
+    for a in attributes:
+        """xpidl methods take care of string member variables!"""
+        firstCapName = firstCap(a.name)
+        cleanNativeType = a.realtype.nativeType('in').strip('* ')
+        if a.realtype.nativeType('in').count("nsAString"):
+            continue
+        elif a.realtype.nativeType('in').count("nsIVariant"):
+            fd.write("  void Get%s(JSContext* aCx, JS::MutableHandle<JS::Value> aRetval, ErrorResult& aRv);\n\n" % firstCapName);
+        elif a.realtype.nativeType('in').endswith('*'):
+            fd.write("  already_AddRefed<%s> Get%s()\n" % (xpidl_to_native(cleanNativeType, conf), firstCapName))
+            fd.write("  {\n");
+            fd.write("    nsCOMPtr<%s> %s = do_QueryInterface(m%s);\n" % (xpidl_to_canonical(cleanNativeType, conf), a.name, firstCapName))
+            fd.write("    return %s.forget().downcast<%s>();\n" % (a.name, xpidl_to_native(cleanNativeType, conf)))
+            fd.write("  }\n\n");
+        else:
+            fd.write("  %s %s()\n" % (cleanNativeType, firstCapName))
+            fd.write("  {\n");
+            fd.write("    return m%s;\n" % firstCapName)
+            fd.write("  }\n\n");
+
+    fd.write("  void ")
+    fd.write("Init%s(" % eventname)
+    if hasVariant:
+        fd.write("JSContext* aCx, ")
+    fd.write("const nsAString& aType, bool aCanBubble, bool aCancelable")
+    for a in allattributes:
+        writeNativeAttributeParams(fd, a, conf)
+    fd.write(", ErrorResult& aRv);\n\n")
+
+    fd.write("protected:\n")
+    for a in attributes:
+        fd.write("  %s\n" % attributeVariableTypeAndName(a))
+    fd.write("};\n")
+
+def collect_names_and_non_primitive_attribute_types(idl, attrnames, forwards):
+    for p in idl.productions:
+        if p.kind == 'interface' or p.kind == 'dictionary':
+            interfaces = []
+            base = p.base
+            baseiface = p
+            while base is not None:
+                baseiface = baseiface.idl.getName(baseiface.base, baseiface.location)    
+                interfaces.append(baseiface)
+                base = baseiface.base
+
+            interfaces.reverse()
+            interfaces.append(p)
+
+            for iface in interfaces:
+                collect_names_and_non_primitive_attribute_types_from_interface(iface, attrnames, forwards)
+
+def collect_names_and_non_primitive_attribute_types_from_interface(iface, attrnames, forwards):
+    for member in iface.members:
+        if isinstance(member, xpidl.Attribute):
+            if not member.name in attrnames:
+                attrnames.append(member.name)
+            if member.realtype.nativeType('in').endswith('*'):
+                t = member.realtype.nativeType('in').strip('* ')
+                if not t in forwards:
+                    forwards.append(t)
+
+def print_cpp(idl, fd, conf, eventname):
+    for p in idl.productions:
+        if p.kind == 'interface':
+            write_cpp(eventname, p, fd, conf)
+
+def print_cpp_file(fd, conf):
+    fd.write("/* THIS FILE IS AUTOGENERATED - DO NOT EDIT */\n\n")
+    fd.write('#include "GeneratedEventClasses.h"\n')
+    fd.write('#include "xpcprivate.h"\n');
+    fd.write('#include "mozilla/dom/Event.h"\n');
+    fd.write('#include "mozilla/dom/EventTarget.h"\n');
+
+    for e in conf.simple_events:
+        idl = loadEventIDL(p, options.incdirs, e)
+        print_cpp(idl, fd, conf, e)
+
+def init_value(attribute):
+    realtype = attribute.realtype.nativeType('in')
+    realtype = realtype.strip(' ')
+    if realtype.endswith('*'):
+        return "nullptr"
+    if realtype == "bool":
+        return "false"
+    if realtype.count("nsAString"):
+        return ""
+    if realtype.count("nsACString"):
+        return ""
+    if realtype.count("JS::Value"):
+      raise BaseException("JS::Value not supported in simple events!")
+    return "0"
+
+def attributeVariableTypeAndName(a):
+    if a.realtype.nativeType('in').endswith('*'):
+        l = ["nsCOMPtr<%s> m%s;" % (a.realtype.nativeType('in').strip('* '),
+                   firstCap(a.name))]
+    elif a.realtype.nativeType('in').count("nsAString"):
+        l = ["nsString m%s;" % firstCap(a.name)]
+    elif a.realtype.nativeType('in').count("nsACString"):
+        l = ["nsCString m%s;" % firstCap(a.name)]
+    else:
+        l = ["%sm%s;" % (a.realtype.nativeType('in'),
+                       firstCap(a.name))]
+    return ", ".join(l)
+
+def writeAttributeGetter(fd, classname, a):
+    fd.write("NS_IMETHODIMP\n")
+    fd.write("%s::Get%s(" % (classname, firstCap(a.name)))
+    if a.realtype.nativeType('in').endswith('*'):
+        fd.write("%s** a%s" % (a.realtype.nativeType('in').strip('* '), firstCap(a.name)))
+    elif a.realtype.nativeType('in').count("nsAString"):
+        fd.write("nsAString& a%s" % firstCap(a.name))
+    elif a.realtype.nativeType('in').count("nsACString"):
+        fd.write("nsACString& a%s" % firstCap(a.name))
+    else:
+        fd.write("%s*a%s" % (a.realtype.nativeType('in'), firstCap(a.name)))
+    fd.write(")\n");
+    fd.write("{\n");
+    if a.realtype.nativeType('in').endswith('*'):
+        fd.write("  NS_IF_ADDREF(*a%s = m%s);\n" % (firstCap(a.name), firstCap(a.name)))
+    elif a.realtype.nativeType('in').count("nsAString"):
+        fd.write("  a%s = m%s;\n" % (firstCap(a.name), firstCap(a.name)))
+    elif a.realtype.nativeType('in').count("nsACString"):
+        fd.write("  a%s = m%s;\n" % (firstCap(a.name), firstCap(a.name)))
+    else:
+        fd.write("  *a%s = %s();\n" % (firstCap(a.name), firstCap(a.name)))
+    fd.write("  return NS_OK;\n");
+    fd.write("}\n\n");
+    if a.realtype.nativeType('in').count("nsIVariant"):
+        fd.write("void\n")
+        fd.write("%s::Get%s(JSContext* aCx, JS::MutableHandle<JS::Value> aRetval, ErrorResult& aRv)\n" % (classname, firstCap(a.name)))
+        fd.write("{\n")
+        fd.write("  nsresult rv = NS_ERROR_UNEXPECTED;\n")
+        fd.write("  if (!m%s) {\n" % firstCap(a.name))
+        fd.write("    aRetval.setNull();\n")
+        fd.write("  } else if (!XPCVariant::VariantDataToJS(m%s, &rv, aRetval)) {\n" % (firstCap(a.name)))
+        fd.write("    aRv.Throw(NS_ERROR_FAILURE);\n")
+        fd.write("  }\n")
+        fd.write("}\n\n")
+
+def writeAttributeParams(fd, a):
+    if a.realtype.nativeType('in').endswith('*'):
+        fd.write(", %s* a%s" % (a.realtype.nativeType('in').strip('* '), firstCap(a.name)))
+    elif a.realtype.nativeType('in').count("nsAString"):
+        fd.write(", const nsAString& a%s" % firstCap(a.name))
+    elif a.realtype.nativeType('in').count("nsACString"):
+        fd.write(", const nsACString& a%s" % firstCap(a.name))
+    else:
+        fd.write(", %s a%s" % (a.realtype.nativeType('in'), firstCap(a.name)))
+
+def writeNativeAttributeParams(fd, a, conf):
+    if a.type == "nsIVariant":
+        fd.write(", JS::Value a%s" % firstCap(a.name));
+    elif a.realtype.nativeType('in').endswith('*'):
+        fd.write(", %s* a%s" % (xpidl_to_native(a.realtype.nativeType('in').strip('* '), conf), firstCap(a.name)))
+    elif a.realtype.nativeType('in').count("nsAString"):
+        fd.write(", const nsAString& a%s" % firstCap(a.name))
+    elif a.realtype.nativeType('in').count("nsACString"):
+        fd.write(", const nsACString& a%s" % firstCap(a.name))
+    else:
+        fd.write(", %s a%s" % (a.realtype.nativeType('in'), firstCap(a.name)))
+
+def write_cpp(eventname, iface, fd, conf):
+    classname = ("%s" % eventname)
+    basename = getBaseName(iface)
+    attributes = []
+    ccattributes = []
+    for member in iface.members:
+        if isinstance(member, xpidl.Attribute):
+            attributes.append(member)
+            if (member.realtype.nativeType('in').endswith('*')):
+                ccattributes.append(member);
+
+    baseinterfaces = []
+    baseiface = iface.idl.getName(iface.base, iface.location)
+    while baseiface.name != "nsIDOMEvent":
+        baseinterfaces.append(baseiface)
+        baseiface = baseiface.idl.getName(baseiface.base, baseiface.location)
+    baseinterfaces.reverse()
+
+    baseattributes = []
+    for baseiface in baseinterfaces:
+        for member in baseiface.members:
+            if isinstance(member, xpidl.Attribute):
+                baseattributes.append(member)
+
+    allattributes = []
+    allattributes.extend(baseattributes);
+    allattributes.extend(attributes);
+
+    fd.write("namespace mozilla {\n")
+    fd.write("namespace dom {\n\n")
+
+    fd.write("%s::%s(mozilla::dom::EventTarget* aOwner, " % (classname, classname))
+    fd.write("nsPresContext* aPresContext, mozilla::WidgetEvent* aEvent)\n");
+    fd.write(": %s(aOwner, aPresContext, aEvent)" % basename)
+    for a in attributes:
+        fd.write(",\n  m%s(%s)" % (firstCap(a.name), init_value(a)))
+    fd.write("\n{\n")
+    fd.write("}\n\n")
+
+    fd.write("%s::~%s() {}\n\n" % (classname, classname))
+
+    fd.write("NS_IMPL_CYCLE_COLLECTION_CLASS(%s)\n" % (classname))
+    fd.write("NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(%s, %s)\n" % (classname, basename))
+    for c in ccattributes:
+        fd.write("  NS_IMPL_CYCLE_COLLECTION_UNLINK(m%s)\n" % firstCap(c.name))
+    fd.write("NS_IMPL_CYCLE_COLLECTION_UNLINK_END\n\n");
+    fd.write("NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(%s, %s)\n" % (classname, basename))
+    for c in ccattributes:
+        fd.write("  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(m%s)\n" % firstCap(c.name))
+    fd.write("NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END\n\n");
+
+    fd.write("NS_IMPL_ADDREF_INHERITED(%s, %s)\n" % (classname, basename))
+    fd.write("NS_IMPL_RELEASE_INHERITED(%s, %s)\n\n" % (classname, basename))
+
+    fd.write("NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(%s)\n" % classname)
+    fd.write("  NS_INTERFACE_MAP_ENTRY(nsIDOM%s)\n" % eventname)
+    fd.write("NS_INTERFACE_MAP_END_INHERITING(%s)\n\n" % basename)
+
+    hasVariant = False
+    for a in allattributes:
+        if a.type == "nsIVariant":
+            hasVariant = True
+            break;
+
+    fd.write("already_AddRefed<%s>\n" % eventname)
+    fd.write("%s::Constructor(const GlobalObject& aGlobal, " % eventname)
+    if hasVariant:
+        fd.write("JSContext* aCx, ");
+    fd.write("const nsAString& aType, ")
+    fd.write("const %sInit& aParam, " % eventname)
+    fd.write("ErrorResult& aRv)\n")
+    fd.write("{\n")
+    fd.write("  nsCOMPtr<mozilla::dom::EventTarget> t = do_QueryInterface(aGlobal.GetAsSupports());\n")
+    fd.write("  nsRefPtr<%s> e = new %s(t, nullptr, nullptr);\n" % (eventname, eventname))
+    fd.write("  bool trusted = e->Init(t);\n")
+    fd.write("  e->Init%s(" % eventname)
+    if hasVariant:
+        fd.write("aCx, ");
+    fd.write("aType, aParam.mBubbles, aParam.mCancelable")
+    for a in allattributes:
+        fd.write(", aParam.m%s" % firstCap(a.name))
+    fd.write(", aRv);\n")
+    fd.write("  e->SetTrusted(trusted);\n")
+    fd.write("  return e.forget();\n")
+    fd.write("}\n\n")
+
+    fd.write("NS_IMETHODIMP\n")
+    fd.write("%s::Init%s(" % (classname, eventname))
+    fd.write("const nsAString& aType, bool aCanBubble, bool aCancelable")
+    for a in allattributes:
+        writeAttributeParams(fd, a)
+    fd.write(")\n{\n")
+    fd.write("  nsresult rv = %s::Init%s(aType, aCanBubble, aCancelable" % (basename, ("%s" % iface.base[6:])))
+    for a in baseattributes:
+      fd.write(", a%s" % firstCap(a.name))
+    fd.write(");\n");
+    fd.write("  NS_ENSURE_SUCCESS(rv, rv);\n")
+    for a in attributes:
+        if a.realtype.nativeType("in").count("nsAString"):
+            fd.write("  if (!m%s.Assign(a%s, fallible_t())) {\n" % (firstCap(a.name), firstCap(a.name)))
+            fd.write("    return NS_ERROR_OUT_OF_MEMORY;\n")
+            fd.write("  }\n")
+        else:
+            fd.write("  m%s = a%s;\n" % (firstCap(a.name), firstCap(a.name)))
+    fd.write("  return NS_OK;\n")
+    fd.write("}\n\n")
+
+    fd.write("void\n")
+    fd.write("%s::Init%s(" % (classname, eventname))
+    if hasVariant:
+        fd.write("JSContext* aCx, ")
+    fd.write("const nsAString& aType, bool aCanBubble, bool aCancelable")
+    for a in allattributes:
+        writeNativeAttributeParams(fd, a, conf)
+    fd.write(", ErrorResult& aRv")
+    fd.write(")\n")
+    fd.write("{\n");
+    for a in allattributes:
+        if a.type == "nsIVariant":
+            fd.write("  nsCOMPtr<nsIVariant> %s = dont_AddRef(XPCVariant::newVariant(aCx, a%s));\n" % (a.name, firstCap(a.name)))
+            fd.write("  if (!%s) {\n" % a.name)
+            fd.write("    aRv.Throw(NS_ERROR_FAILURE);\n")
+            fd.write("    return;\n")
+            fd.write("  }\n")
+        elif a.realtype.nativeType('in').endswith('*'):
+            xpidl_t = a.realtype.nativeType('in').strip('* ')
+            native_t = xpidl_to_native(xpidl_t, conf)
+            if xpidl_t != native_t:
+                fd.write("  nsCOMPtr<%s> %s = do_QueryInterface(static_cast<%s*>(a%s));\n" % (xpidl_t, a.name, xpidl_to_canonical(xpidl_t, conf), firstCap(a.name)))
+    fd.write("  aRv = Init%s(" % classname);
+    fd.write("aType, aCanBubble, aCancelable")
+    for a in allattributes:
+        if a.realtype.nativeType('in').endswith('*'):
+            xpidl_t = a.realtype.nativeType('in').strip('* ')
+            native_t = xpidl_to_native(xpidl_t, conf)
+            if xpidl_t != native_t or a.type == "nsIVariant":
+                fd.write(", %s" % a.name)
+                continue
+        fd.write(", a%s" % firstCap(a.name))
+    fd.write(");\n}\n\n");
+
+    for a in attributes:
+        writeAttributeGetter(fd, classname, a)
+
+    fd.write("} // namespace dom\n")
+    fd.write("} // namespace mozilla\n\n")
+
+    fd.write("nsresult\n")
+    fd.write("NS_NewDOM%s(nsIDOMEvent** aInstance, "  % eventname)
+    fd.write("mozilla::dom::EventTarget* aOwner, nsPresContext* aPresContext = nullptr, mozilla::WidgetEvent* aEvent = nullptr)\n")
+    fd.write("{\n")
+    fd.write("  mozilla::dom::%s* it = new mozilla::dom::%s(aOwner, aPresContext, aEvent);\n" % (classname, classname))
+    fd.write("  NS_ADDREF(it);\n")
+    fd.write("  *aInstance = static_cast<mozilla::dom::Event*>(it);\n")
+    fd.write("  return NS_OK;\n");
+    fd.write("}\n\n")
+
+def toWebIDLType(attribute, inType=False, onlyInterface=False):
+    if attribute.type == "nsIVariant":
+        return "any";
+    if attribute.type == "nsISupports":
+        return "%s%s" % (attribute.type, "" if onlyInterface else "?")
+    if attribute.type.count("nsIDOM"):
+        return "%s%s" % (attribute.type[6:], "" if onlyInterface else "?")
+    if attribute.type.count("nsI"):
+        return "%s%s" % (attribute.type[3:], "" if onlyInterface else "?")
+    if attribute.realtype.nativeType('in').endswith('*') or attribute.realtype.nativeType('in').count("nsAString"):
+        return "%s%s" % (attribute.type, "" if onlyInterface else "?")
+    return attribute.type
+
+def write_webidl(eventname, iface, fd, conf, idl):
+    basename = ("%s" % iface.base[6:])
+    attributes = []
+    ccattributes = []
+    consts = []
+    hasInit = False
+    initMethod = "init%s" % eventname;
+    for member in iface.members:
+        if isinstance(member, xpidl.Attribute):
+            attributes.append(member)
+            if (member.realtype.nativeType('in').endswith('*')):
+                ccattributes.append(member);
+        elif isinstance(member, xpidl.Method) and member.name == initMethod:
+            if not member.noscript and not member.notxpcom:
+                hasInit = True
+        elif isinstance(member, xpidl.ConstMember):
+            consts.append(member);
+        else:
+            raise BaseException("Unsupported idl member %s::%s" % (eventname, member.name))
+
+    baseinterfaces = []
+    baseiface = iface.idl.getName(iface.base, iface.location)
+    while baseiface.name != "nsIDOMEvent":
+        baseinterfaces.append(baseiface)
+        baseiface = baseiface.idl.getName(baseiface.base, baseiface.location)
+    baseinterfaces.reverse()
+
+    allattributes = []
+    for baseiface in baseinterfaces:
+        for member in baseiface.members:
+            if isinstance(member, xpidl.Attribute):
+                allattributes.append(member)
+    allattributes.extend(attributes)
+
+    fd.write(
+"""/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+""")
+
+    neededInterfaces = []
+    for a in attributes:
+        if a.realtype.nativeType('in').endswith('*'):
+            nativeType = a.realtype.nativeType('in').strip('* ')
+            mappingForWebIDL = False
+            for xp in conf.xpidl_to_native:
+                if xp[0] == nativeType:
+                    mappingForWebIDL = True
+                    break;
+            if not mappingForWebIDL:
+                webidlType = toWebIDLType(a, False, True)
+                if (not webidlType in neededInterfaces and webidlType != "any"):
+                    neededInterfaces.append(webidlType);
+
+    for i in neededInterfaces:
+        fd.write("interface %s;\n" % i)
+
+    fd.write("\n");
+    fd.write("[Constructor(DOMString type, optional %sInit eventInitDict), HeaderFile=\"GeneratedEventClasses.h\"]\n" % eventname);
+    fd.write("interface %s : %s\n" % (eventname, basename))
+    fd.write("{\n")
+
+    for c in consts:
+        fd.write("  const %s %s = %s;\n" % (c.type, c.name, c.getValue()))
+    if len(consts):
+        fd.write("\n")
+
+    for a in attributes:
+        if a.realtype.nativeType('in').count("nsIVariant"):
+            fd.write("  [Throws]\n")
+            fd.write("  readonly attribute %s %s;\n" % (toWebIDLType(a), a.name))
+        elif a.realtype.nativeType('in').endswith('*') or a.realtype.nativeType('in').count("nsAString"):
+            fd.write("  readonly attribute %s %s;\n" % (toWebIDLType(a), a.name))
+        else:
+            fd.write("  readonly attribute %s %s;\n" % (a.type, a.name))
+    if hasInit:
+        fd.write("\n  [Throws]\n")
+        m = "  void %s(" % initMethod
+        fd.write(m)
+        indent = "".join(" " for i in range(len(m)))
+        indent = ",\n%s" % indent
+        fd.write("DOMString type")
+        fd.write(indent);
+        fd.write("boolean canBubble")
+        fd.write(indent);
+        fd.write("boolean cancelable")
+        for a in baseattributes + attributes:
+            fd.write(indent);
+            fd.write("%s %s" % (toWebIDLType(a, True), a.name))
+        fd.write(");\n");
+    fd.write("};\n\n")
+
+    dname = "%sInit" % eventname
+    for p in idl.productions:
+        if p.kind == "dictionary" and p.name == dname:
+            fd.write("dictionary %s : %sInit\n" % (dname, basename))
+            fd.write("{\n")
+            # We want to keep the same ordering what interface has.
+            for ifaceattribute in attributes:
+                for member in p.members:
+                    if member.name == ifaceattribute.name:
+                        a = member
+                        if a.realtype.nativeType('in').endswith('*'):
+                            fd.write("  %s %s = null;\n" % (toWebIDLType(a, True), a.name))
+                        elif a.realtype.nativeType('in').count("nsAString"):
+                            if a.defvalue is None:
+                                if a.nullable:
+                                    fd.write("  %s? %s = null;\n" % (a.type, a.name))
+                                else:
+                                    fd.write("  %s %s = \"\";\n" % (a.type, a.name))
+                            else:
+                                if a.nullable:
+                                    fd.write("  %s? %s = \"%s\";\n" % (a.type, a.name, a.defvalue))
+                                else:
+                                    fd.write("  %s %s = \"%s\";\n" % (a.type, a.name, a.defvalue))
+                        else:
+                            if a.defvalue is None:
+                                if a.type == "boolean":
+                                    fd.write("  %s %s = false;\n" % (a.type, a.name))
+                                else:
+                                    fd.write("  %s %s = 0;\n" % (a.type, a.name))
+                            # Infinity is not supported by all the types, but
+                            # WebIDL parser will then complain about the wrong values.
+                            elif a.defvalue == "Infinity":
+                                fd.write("  unrestricted %s %s = Infinity;\n" % (a.type, a.name))
+                            elif a.defvalue == "-Infinity":
+                                fd.write("  unrestricted %s %s = -Infinity;\n" % (a.type, a.name))
+                            else:
+                                fd.write("  %s %s = %s;\n" % (a.type, a.name, a.defvalue))
+                    continue
+            fd.write("};\n")
+            return
+
+    # There is no dictionary defined in the .idl file. Generate one based on
+    # the interface.
+    fd.write("dictionary %s : %sInit\n" % (dname, basename))
+    fd.write("{\n")
+    for a in attributes:
+        if a.realtype.nativeType('in').endswith('*'):
+            fd.write("  %s %s = null;\n" % (toWebIDLType(a, True), a.name))
+        elif a.realtype.nativeType('in').count("nsAString"):
+            fd.write("  %s? %s = \"\";\n" % (a.type, a.name))
+        elif a.type == "boolean":
+            fd.write("  %s %s = false;\n" % (a.type, a.name))
+        else:
+            fd.write("  %s %s = 0;\n" % (a.type, a.name))
+    fd.write("};\n")
+
+def print_webidl_file(idl, fd, conf, eventname):
+    for p in idl.productions:
+        if p.kind == 'interface':
+            write_webidl(eventname, p, fd, conf, idl)
+
+def xpidl_to_native(xpidl, conf):
+    for x in conf.xpidl_to_native:
+        if x[0] == xpidl:
+            return x[1]
+    return xpidl
+
+def xpidl_to_canonical(xpidl, conf):
+    for x in conf.xpidl_to_native:
+        if x[0] == xpidl:
+            return x[2]
+    return xpidl
+
+def native_to_xpidl(native, conf):
+    for x in conf.xpidl_to_native:
+        if x[1] == native:
+            return x[0]
+    return native
+
+def print_webidl_files(webidlDir, conf):
+    for e in conf.simple_events:
+        idl = loadEventIDL(p, options.incdirs, e)
+        webidl = "%s/%s.webidl" % (webidlDir, e)
+        if not os.path.exists(webidl):
+            fd = open(webidl, 'w')
+            print_webidl_file(idl, fd, conf, e)
+            fd.close();
+
+if __name__ == '__main__':
+    from optparse import OptionParser
+    o = OptionParser(usage="usage: %prog [options] configfile")
+    o.add_option('-I', action='append', dest='incdirs', default=['.'],
+                 help="Directory to search for imported files")
+    o.add_option('-o', "--stub-output",
+                 type='string', dest='stub_output', default=None,
+                 help="Quick stub C++ source output file", metavar="FILE")
+    o.add_option('--header-output', type='string', default=None,
+                 help="Quick stub header output file", metavar="FILE")
+    o.add_option('--makedepend-output', type='string', default=None,
+                 help="gnumake dependencies output file", metavar="FILE")
+    o.add_option('--cachedir', dest='cachedir', default=None,
+                 help="Directory in which to cache lex/parse tables.")
+    o.add_option('--class-declarations', type='string', default=None,
+                 help="Class declarations", metavar="FILE")
+    o.add_option('--webidltarget', dest='webidltarget', default=None,
+                 help="Directory in which to store generated WebIDL files.")
+    (options, filenames) = o.parse_args()
+    if len(filenames) != 1:
+        o.error("Exactly one config filename is needed.")
+    filename = filenames[0]
+
+    if options.cachedir is not None:
+        if not os.path.isdir(options.cachedir):
+            os.mkdir(options.cachedir)
+        sys.path.append(options.cachedir)
+
+    # Instantiate the parser.
+    p = xpidl.IDLParser(outputdir=options.cachedir)
+
+    conf = readConfigFile(filename)
+
+    if options.header_output is not None:
+        outfd = open(options.header_output, 'w')
+        print_header_file(outfd, conf)
+        outfd.close()
+    if options.class_declarations is not None:
+        outfd = open(options.class_declarations, 'w')
+        print_classes_file(outfd, conf)
+        outfd.close()
+    if options.stub_output is not None:
+        makeutils.targets.append(options.stub_output)
+        outfd = open(options.stub_output, 'w')
+        print_cpp_file(outfd, conf)
+        outfd.close()
+        if options.makedepend_output is not None:
+            makeutils.writeMakeDependOutput(options.makedepend_output)
+
+    if options.webidltarget is not None:
+        print_webidl_files(options.webidltarget, conf)
+