Move ModuleSystem and NativeHandler to extensions/

chrome/renderer/module_system.cc

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "chrome/renderer/module_system.h"
-
-#include "base/bind.h"
-#include "third_party/WebKit/Source/WebKit/chromium/public/WebScopedMicrotaskSuppression.h"
-
-namespace {
-
-const char* kModuleSystem = "module_system";
-const char* kModuleName = "module_name";
-const char* kModuleField = "module_field";
-const char* kModulesField = "modules";
-
-} // namespace
-
-ModuleSystem::ModuleSystem(v8::Handle<v8::Context> context,
-                           SourceMap* source_map)
-    : context_(v8::Persistent<v8::Context>::New(context)),
-      source_map_(source_map),
-      natives_enabled_(0) {
-  RouteFunction("require",
-      base::Bind(&ModuleSystem::RequireForJs, base::Unretained(this)));
-  RouteFunction("requireNative",
-      base::Bind(&ModuleSystem::GetNative, base::Unretained(this)));
-
-  v8::Handle<v8::Object> global(context_->Global());
-  global->SetHiddenValue(v8::String::New(kModulesField), v8::Object::New());
-  global->SetHiddenValue(v8::String::New(kModuleSystem),
-                         v8::External::New(this));
-}
-
-ModuleSystem::~ModuleSystem() {
-  v8::HandleScope handle_scope;
-  // Deleting this value here prevents future lazy field accesses from
-  // referencing ModuleSystem after it has been freed.
-  context_->Global()->DeleteHiddenValue(v8::String::New(kModuleSystem));
-  context_.Dispose();
-}
-
-ModuleSystem::NativesEnabledScope::NativesEnabledScope(
-    ModuleSystem* module_system)
-    : module_system_(module_system) {
-  module_system_->natives_enabled_++;
-}
-
-ModuleSystem::NativesEnabledScope::~NativesEnabledScope() {
-  module_system_->natives_enabled_--;
-  CHECK_GE(module_system_->natives_enabled_, 0);
-}
-
-// static
-bool ModuleSystem::IsPresentInCurrentContext() {
-  v8::Handle<v8::Object> global(v8::Context::GetCurrent()->Global());
-  v8::Handle<v8::Value> module_system =
-      global->GetHiddenValue(v8::String::New(kModuleSystem));
-  return !module_system.IsEmpty() && !module_system->IsUndefined();
-}
-
-// static
-void ModuleSystem::DumpException(const v8::TryCatch& try_catch) {
-  v8::HandleScope handle_scope;
-
-  v8::Handle<v8::Message> message(try_catch.Message());
-  if (message.IsEmpty()) {
-    LOG(ERROR) << "try_catch has no message";
-    return;
-  }
-
-  std::string resource_name = "<unknown resource>";
-  if (!message->GetScriptResourceName().IsEmpty()) {
-    resource_name =
-        *v8::String::Utf8Value(message->GetScriptResourceName()->ToString());
-  }
-
-  std::string error_message = "<no error message>";
-  if (!message->Get().IsEmpty())
-    error_message = *v8::String::Utf8Value(message->Get());
-
-  std::string stack_trace = "<stack trace unavailable>";
-  if (!try_catch.StackTrace().IsEmpty()) {
-    v8::String::Utf8Value stack_value(try_catch.StackTrace());
-    if (*stack_value)
-      stack_trace.assign(*stack_value, stack_value.length());
-    else
-      stack_trace = "<could not convert stack trace to string>";
-  }
-
-  LOG(ERROR) << "[" << resource_name << "(" << message->GetLineNumber() << ")] "
-             << error_message
-             << "{" << stack_trace << "}";
-}
-
-void ModuleSystem::Require(const std::string& module_name) {
-  v8::HandleScope handle_scope;
-  RequireForJsInner(v8::String::New(module_name.c_str()));
-}
-
-v8::Handle<v8::Value> ModuleSystem::RequireForJs(const v8::Arguments& args) {
-  v8::HandleScope handle_scope;
-  v8::Handle<v8::String> module_name = args[0]->ToString();
-  return handle_scope.Close(RequireForJsInner(module_name));
-}
-
-v8::Handle<v8::Value> ModuleSystem::RequireForJsInner(
-    v8::Handle<v8::String> module_name) {
-  v8::HandleScope handle_scope;
-  v8::Handle<v8::Object> global(v8::Context::GetCurrent()->Global());
-  v8::Handle<v8::Object> modules(v8::Handle<v8::Object>::Cast(
-      global->GetHiddenValue(v8::String::New(kModulesField))));
-  v8::Handle<v8::Value> exports(modules->Get(module_name));
-  if (!exports->IsUndefined())
-    return handle_scope.Close(exports);
-
-  v8::Handle<v8::Value> source(GetSource(module_name));
-  if (source->IsUndefined())
-    return handle_scope.Close(v8::Undefined());
-  v8::Handle<v8::String> wrapped_source(WrapSource(
-      v8::Handle<v8::String>::Cast(source)));
-  v8::Handle<v8::Function> func =
-      v8::Handle<v8::Function>::Cast(RunString(wrapped_source, module_name));
-  if (func.IsEmpty()) {
-    return ThrowException(std::string(*v8::String::AsciiValue(module_name)) +
-        ": Bad source");
-  }
-
-  exports = v8::Object::New();
-  v8::Handle<v8::Object> natives(NewInstance());
-  v8::Handle<v8::Value> args[] = {
-    natives->Get(v8::String::NewSymbol("require")),
-    natives->Get(v8::String::NewSymbol("requireNative")),
-    exports,
-  };
-  {
-    WebKit::WebScopedMicrotaskSuppression suppression;
-    v8::TryCatch try_catch;
-    try_catch.SetCaptureMessage(true);
-    func->Call(global, 3, args);
-    if (try_catch.HasCaught()) {
-      DumpException(try_catch);
-      return v8::Undefined();
-    }
-  }
-  modules->Set(module_name, exports);
-  return handle_scope.Close(exports);
-}
-
-void ModuleSystem::RegisterNativeHandler(const std::string& name,
-    scoped_ptr<NativeHandler> native_handler) {
-  native_handler_map_[name] =
-      linked_ptr<NativeHandler>(native_handler.release());
-}
-
-void ModuleSystem::OverrideNativeHandler(const std::string& name) {
-  overridden_native_handlers_.insert(name);
-}
-
-void ModuleSystem::RunString(const std::string& code, const std::string& name) {
-  v8::HandleScope handle_scope;
-  RunString(v8::String::New(code.c_str()), v8::String::New(name.c_str()));
-}
-
-// static
-v8::Handle<v8::Value> ModuleSystem::LazyFieldGetter(
-    v8::Local<v8::String> property, const v8::AccessorInfo& info) {
-  CHECK(!info.Data().IsEmpty());
-  CHECK(info.Data()->IsObject());
-  v8::HandleScope handle_scope;
-  v8::Handle<v8::Object> parameters = v8::Handle<v8::Object>::Cast(info.Data());
-  v8::Handle<v8::Object> global(v8::Context::GetCurrent()->Global());
-  v8::Handle<v8::Value> module_system_value =
-      global->GetHiddenValue(v8::String::New(kModuleSystem));
-  if (module_system_value->IsUndefined()) {
-    // ModuleSystem has been deleted.
-    return v8::Undefined();
-  }
-  ModuleSystem* module_system = static_cast<ModuleSystem*>(
-      v8::Handle<v8::External>::Cast(module_system_value)->Value());
-
-  v8::Handle<v8::Object> module;
-  {
-    NativesEnabledScope scope(module_system);
-    module = v8::Handle<v8::Object>::Cast(module_system->RequireForJsInner(
-        parameters->Get(v8::String::New(kModuleName))->ToString()));
-  }
-  if (module.IsEmpty())
-    return handle_scope.Close(v8::Handle<v8::Value>());
-
-  v8::Handle<v8::String> field =
-      parameters->Get(v8::String::New(kModuleField))->ToString();
-
-  return handle_scope.Close(module->Get(field));
-}
-
-void ModuleSystem::SetLazyField(v8::Handle<v8::Object> object,
-                                const std::string& field,
-                                const std::string& module_name,
-                                const std::string& module_field) {
-  v8::HandleScope handle_scope;
-  v8::Handle<v8::Object> parameters = v8::Object::New();
-  parameters->Set(v8::String::New(kModuleName),
-                  v8::String::New(module_name.c_str()));
-  parameters->Set(v8::String::New(kModuleField),
-                  v8::String::New(module_field.c_str()));
-
-  object->SetAccessor(v8::String::New(field.c_str()),
-                      &ModuleSystem::LazyFieldGetter,
-                      NULL,
-                      parameters);
-}
-
-v8::Handle<v8::Value> ModuleSystem::RunString(v8::Handle<v8::String> code,
-                                              v8::Handle<v8::String> name) {
-  v8::HandleScope handle_scope;
-  WebKit::WebScopedMicrotaskSuppression suppression;
-  v8::Handle<v8::Value> result;
-  v8::TryCatch try_catch;
-  try_catch.SetCaptureMessage(true);
-  v8::Handle<v8::Script> script(v8::Script::New(code, name));
-  if (try_catch.HasCaught()) {
-    DumpException(try_catch);
-    return handle_scope.Close(result);
-  }
-
-  result = script->Run();
-  if (try_catch.HasCaught())
-    DumpException(try_catch);
-
-  return handle_scope.Close(result);
-}
-
-v8::Handle<v8::Value> ModuleSystem::GetSource(
-    v8::Handle<v8::String> source_name) {
-  v8::HandleScope handle_scope;
-  std::string module_name = *v8::String::AsciiValue(source_name);
-  if (!source_map_->Contains(module_name))
-    return v8::Undefined();
-  return handle_scope.Close(source_map_->GetSource(module_name));
-}
-
-v8::Handle<v8::Value> ModuleSystem::GetNative(const v8::Arguments& args) {
-  CHECK_EQ(1, args.Length());
-  if (natives_enabled_ == 0)
-    return ThrowException("Natives disabled");
-  std::string native_name = *v8::String::AsciiValue(args[0]->ToString());
-  if (overridden_native_handlers_.count(native_name) > 0u)
-    return RequireForJs(args);
-  NativeHandlerMap::iterator i = native_handler_map_.find(native_name);
-  if (i == native_handler_map_.end())
-    return v8::Undefined();
-  return i->second->NewInstance();
-}
-
-v8::Handle<v8::String> ModuleSystem::WrapSource(v8::Handle<v8::String> source) {
-  v8::HandleScope handle_scope;
-  v8::Handle<v8::String> left =
-      v8::String::New("(function(require, requireNative, exports) {");
-  v8::Handle<v8::String> right = v8::String::New("\n})");
-  return handle_scope.Close(
-      v8::String::Concat(left, v8::String::Concat(source, right)));
-}
-
-v8::Handle<v8::Value> ModuleSystem::ThrowException(const std::string& message) {
-  return v8::ThrowException(v8::String::New(message.c_str()));
-}