atom_api_v8_util.cc

// Copyright (c) 2013 GitHub, Inc.
// Use of this source code is governed by the MIT license that can be
// found in the LICENSE file.

#include <string>
#include <utility>

#include "atom/common/api/atom_api_key_weak_map.h"
#include "atom/common/api/remote_callback_freer.h"
#include "atom/common/api/remote_object_freer.h"
#include "atom/common/native_mate_converters/content_converter.h"
#include "atom/common/native_mate_converters/gurl_converter.h"
#include "atom/common/node_includes.h"
#include "base/hash.h"
#include "base/process/process_handle.h"
#include "base/strings/stringprintf.h"
#include "native_mate/dictionary.h"
#include "url/origin.h"
#include "v8/include/v8-profiler.h"

// This is defined in later versions of Chromium, remove this if you see
// compiler complaining duplicate defines.
#if defined(OS_WIN) || defined(OS_FUCHSIA)
#define CrPRIdPid "ld"
#else
#define CrPRIdPid "d"
#endif

namespace std {

// The hash function used by DoubleIDWeakMap.
template <typename Type1, typename Type2>
struct hash<std::pair<Type1, Type2>> {
  std::size_t operator()(std::pair<Type1, Type2> value) const {
    return base::HashInts(base::Hash(value.first), value.second);
  }
};

}  // namespace std

namespace mate {

template <typename Type1, typename Type2>
struct Converter<std::pair<Type1, Type2>> {
  static bool FromV8(v8::Isolate* isolate,
                     v8::Local<v8::Value> val,
                     std::pair<Type1, Type2>* out) {
    if (!val->IsArray())
      return false;

    v8::Local<v8::Array> array(v8::Local<v8::Array>::Cast(val));
    if (array->Length() != 2)
      return false;
    return Converter<Type1>::FromV8(isolate, array->Get(0), &out->first) &&
           Converter<Type2>::FromV8(isolate, array->Get(1), &out->second);
  }
};

}  // namespace mate

namespace {

v8::Local<v8::Value> GetHiddenValue(v8::Isolate* isolate,
                                    v8::Local<v8::Object> object,
                                    v8::Local<v8::String> key) {
  v8::Local<v8::Context> context = isolate->GetCurrentContext();
  v8::Local<v8::Private> privateKey = v8::Private::ForApi(isolate, key);
  v8::Local<v8::Value> value;
  v8::Maybe<bool> result = object->HasPrivate(context, privateKey);
  if (!(result.IsJust() && result.FromJust()))
    return v8::Local<v8::Value>();
  if (object->GetPrivate(context, privateKey).ToLocal(&value))
    return value;
  return v8::Local<v8::Value>();
}

void SetHiddenValue(v8::Isolate* isolate,
                    v8::Local<v8::Object> object,
                    v8::Local<v8::String> key,
                    v8::Local<v8::Value> value) {
  if (value.IsEmpty())
    return;
  v8::Local<v8::Context> context = isolate->GetCurrentContext();
  v8::Local<v8::Private> privateKey = v8::Private::ForApi(isolate, key);
  object->SetPrivate(context, privateKey, value);
}

void DeleteHiddenValue(v8::Isolate* isolate,
                       v8::Local<v8::Object> object,
                       v8::Local<v8::String> key) {
  v8::Local<v8::Context> context = isolate->GetCurrentContext();
  v8::Local<v8::Private> privateKey = v8::Private::ForApi(isolate, key);
  // Actually deleting the value would make force the object into
  // dictionary mode which is unnecessarily slow. Instead, we replace
  // the hidden value with "undefined".
  object->SetPrivate(context, privateKey, v8::Undefined(isolate));
}

int32_t GetObjectHash(v8::Local<v8::Object> object) {
  return object->GetIdentityHash();
}

std::string GetContextID(v8::Isolate* isolate) {
  // When a page is reloaded, V8 and blink may have optimizations that do not
  // free blink::WebLocalFrame and v8::Context and reuse them for the new page,
  // while we always recreate node::Environment when a page is loaded.
  // So the only reliable way to return an identity for a page, is to return the
  // address of the node::Environment instance.
  node::Environment* env = node::Environment::GetCurrent(isolate);
  return base::StringPrintf("%" CrPRIdPid "-%p", base::GetCurrentProcId(), env);
}

void TakeHeapSnapshot(v8::Isolate* isolate) {
  isolate->GetHeapProfiler()->TakeHeapSnapshot();
}

void RequestGarbageCollectionForTesting(v8::Isolate* isolate) {
  isolate->RequestGarbageCollectionForTesting(
      v8::Isolate::GarbageCollectionType::kFullGarbageCollection);
}

bool IsSameOrigin(const GURL& l, const GURL& r) {
  return url::Origin::Create(l).IsSameOriginWith(url::Origin::Create(r));
}

void Initialize(v8::Local<v8::Object> exports,
                v8::Local<v8::Value> unused,
                v8::Local<v8::Context> context,
                void* priv) {
  mate::Dictionary dict(context->GetIsolate(), exports);
  dict.SetMethod("getHiddenValue", &GetHiddenValue);
  dict.SetMethod("setHiddenValue", &SetHiddenValue);
  dict.SetMethod("deleteHiddenValue", &DeleteHiddenValue);
  dict.SetMethod("getObjectHash", &GetObjectHash);
  dict.SetMethod("getContextId", &GetContextID);
  dict.SetMethod("takeHeapSnapshot", &TakeHeapSnapshot);
  dict.SetMethod("setRemoteCallbackFreer", &atom::RemoteCallbackFreer::BindTo);
  dict.SetMethod("setRemoteObjectFreer", &atom::RemoteObjectFreer::BindTo);
  dict.SetMethod("createIDWeakMap", &atom::api::KeyWeakMap<int32_t>::Create);
  dict.SetMethod(
      "createDoubleIDWeakMap",
      &atom::api::KeyWeakMap<std::pair<std::string, int32_t>>::Create);
  dict.SetMethod("requestGarbageCollectionForTesting",
                 &RequestGarbageCollectionForTesting);
  dict.SetMethod("isSameOrigin", &IsSameOrigin);
}

}  // namespace

NODE_BUILTIN_MODULE_CONTEXT_AWARE(atom_common_v8_util, Initialize)