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// Copyright 2014 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 "extensions/renderer/binding_generating_native_handler.h"
#include "base/macros.h"
#include "base/metrics/histogram_macros.h"
#include "base/timer/elapsed_timer.h"
#include "extensions/renderer/script_context.h"
#include "extensions/renderer/v8_helpers.h"
namespace extensions {
using namespace v8_helpers;
BindingGeneratingNativeHandler::BindingGeneratingNativeHandler(
ScriptContext* context,
const std::string& api_name,
const std::string& bind_to)
: context_(context), api_name_(api_name), bind_to_(bind_to) {}
v8::Local<v8::Object> BindingGeneratingNativeHandler::NewInstance() {
base::ElapsedTimer timer;
// This long sequence of commands effectively runs the JavaScript code,
// such that result[bind_to] is the compiled schema for |api_name|:
//
// var result = {};
// result[bind_to] = require('binding').Binding.create(api_name).generate();
// return result;
//
// Unfortunately using the v8 APIs makes that quite verbose.
// Each stage is marked with the code it executes.
v8::Isolate* isolate = context_->isolate();
v8::EscapableHandleScope scope(isolate);
// Convert |api_name| and |bind_to| into their v8::Strings to pass
// through the v8 APIs.
v8::Local<v8::String> v8_api_name;
v8::Local<v8::String> v8_bind_to;
if (!ToV8String(isolate, api_name_, &v8_api_name) ||
!ToV8String(isolate, bind_to_, &v8_bind_to)) {
NOTREACHED();
return v8::Local<v8::Object>();
}
v8::Local<v8::Context> v8_context = context_->v8_context();
// require('binding');
v8::Local<v8::Object> binding_module;
if (!context_->module_system()->Require("binding").ToLocal(&binding_module)) {
NOTREACHED();
return v8::Local<v8::Object>();
}
// require('binding').Binding;
v8::Local<v8::Value> binding_value;
v8::Local<v8::Object> binding;
if (!GetProperty(v8_context, binding_module, "Binding", &binding_value) ||
!binding_value->ToObject(v8_context).ToLocal(&binding)) {
NOTREACHED();
return v8::Local<v8::Object>();
}
// require('binding').Binding.create;
v8::Local<v8::Value> create_binding_value;
if (!GetProperty(v8_context, binding, "create", &create_binding_value) ||
!create_binding_value->IsFunction()) {
NOTREACHED();
return v8::Local<v8::Object>();
}
v8::Local<v8::Function> create_binding =
create_binding_value.As<v8::Function>();
// require('Binding').Binding.create(api_name);
v8::Local<v8::Value> argv[] = {v8_api_name};
v8::Local<v8::Value> binding_instance_value;
v8::Local<v8::Object> binding_instance;
if (!CallFunction(v8_context, create_binding, binding, arraysize(argv), argv,
&binding_instance_value) ||
!binding_instance_value->ToObject(v8_context)
.ToLocal(&binding_instance)) {
NOTREACHED();
return v8::Local<v8::Object>();
}
// require('binding').Binding.create(api_name).generate;
v8::Local<v8::Value> generate_value;
if (!GetProperty(v8_context, binding_instance, "generate", &generate_value) ||
!generate_value->IsFunction()) {
NOTREACHED();
return v8::Local<v8::Object>();
}
v8::Local<v8::Function> generate = generate_value.As<v8::Function>();
// require('binding').Binding.create(api_name).generate();
v8::Local<v8::Object> object = v8::Object::New(isolate);
v8::Local<v8::Value> compiled_schema;
if (!CallFunction(v8_context, generate, binding_instance, 0, nullptr,
&compiled_schema)) {
NOTREACHED();
return v8::Local<v8::Object>();
}
// var result = {};
// result[bind_to] = ...;
if (!SetProperty(v8_context, object, v8_bind_to, compiled_schema)) {
NOTREACHED();
return v8::Local<v8::Object>();
}
// Log UMA with microsecond accuracy*; maxes at 10 seconds.
// *Obviously, limited by our TimeTicks implementation, but as close as
// possible.
UMA_HISTOGRAM_CUSTOM_COUNTS("Extensions.ApiBindingObjectGenerationTime",
timer.Elapsed().InMicroseconds(),
1, 10000000, 100);
// return result;
return scope.Escape(object);
}
} // namespace extensions
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