node/src/util-inl.h

// Copyright Joyent, Inc. and other Node contributors.
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//
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// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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#ifndef SRC_UTIL_INL_H_
#define SRC_UTIL_INL_H_

#include "util.h"

#include <assert.h>

namespace node {

template <typename Inner, typename Outer>
ContainerOfHelper<Inner, Outer>::ContainerOfHelper(Inner Outer::*field,
                                                   Inner* pointer)
    : pointer_(reinterpret_cast<Outer*>(
          reinterpret_cast<uintptr_t>(pointer) -
          reinterpret_cast<uintptr_t>(&(static_cast<Outer*>(0)->*field)))) {
}

template <typename Inner, typename Outer>
template <typename TypeName>
ContainerOfHelper<Inner, Outer>::operator TypeName*() const {
  return static_cast<TypeName*>(pointer_);
}

template <typename Inner, typename Outer>
inline ContainerOfHelper<Inner, Outer> ContainerOf(Inner Outer::*field,
                                                   Inner* pointer) {
  return ContainerOfHelper<Inner, Outer>(field, pointer);
}

template <class TypeName>
inline v8::Local<TypeName> PersistentToLocal(
    v8::Isolate* isolate,
    const v8::Persistent<TypeName>& persistent) {
  if (persistent.IsWeak()) {
    return WeakPersistentToLocal(isolate, persistent);
  } else {
    return StrongPersistentToLocal(persistent);
  }
}

template <class TypeName>
inline v8::Local<TypeName> StrongPersistentToLocal(
    const v8::Persistent<TypeName>& persistent) {
  return *reinterpret_cast<v8::Local<TypeName>*>(
      const_cast<v8::Persistent<TypeName>*>(&persistent));
}

template <class TypeName>
inline v8::Local<TypeName> WeakPersistentToLocal(
    v8::Isolate* isolate,
    const v8::Persistent<TypeName>& persistent) {
  return v8::Local<TypeName>::New(isolate, persistent);
}

inline v8::Local<v8::String> OneByteString(v8::Isolate* isolate,
                                           const char* data,
                                           int length) {
  return v8::String::NewFromOneByte(isolate,
                                    reinterpret_cast<const uint8_t*>(data),
                                    v8::String::kNormalString,
                                    length);
}

inline v8::Local<v8::String> OneByteString(v8::Isolate* isolate,
                                           const signed char* data,
                                           int length) {
  return v8::String::NewFromOneByte(isolate,
                                    reinterpret_cast<const uint8_t*>(data),
                                    v8::String::kNormalString,
                                    length);
}

inline v8::Local<v8::String> OneByteString(v8::Isolate* isolate,
                                           const unsigned char* data,
                                           int length) {
  return v8::String::NewFromOneByte(isolate,
                                    reinterpret_cast<const uint8_t*>(data),
                                    v8::String::kNormalString,
                                    length);
}

template <typename TypeName>
void Wrap(v8::Local<v8::Object> object, TypeName* pointer) {
  assert(!object.IsEmpty());
  assert(object->InternalFieldCount() > 0);
  object->SetAlignedPointerInInternalField(0, pointer);
}

void ClearWrap(v8::Local<v8::Object> object) {
  Wrap<void>(object, NULL);
}

template <typename TypeName>
TypeName* Unwrap(v8::Local<v8::Object> object) {
  assert(!object.IsEmpty());
  assert(object->InternalFieldCount() > 0);
  void* pointer = object->GetAlignedPointerFromInternalField(0);
  return static_cast<TypeName*>(pointer);
}

}  // namespace node

#endif  // SRC_UTIL_INL_H_