v8.h.svn-base

Google浏览器V8内核代码

 * the kind of cross-context access that should be allowed.
 */
enum AccessControl {
  DEFAULT         = 0,
  ALL_CAN_READ    = 1,
  ALL_CAN_WRITE   = 2
};


/**
 * Access type specification.
 */
enum AccessType {
  ACCESS_GET,
  ACCESS_SET,
  ACCESS_HAS,
  ACCESS_DELETE,
  ACCESS_KEYS
};


/**
 * Returns true if cross-context access should be allowed to the named
 * property with the given key on the global object.
 */
typedef bool (*NamedSecurityCallback)(Local<Object> global,
                                      Local<Value> key,
                                      AccessType type,
                                      Local<Value> data);


/**
 * Returns true if cross-context access should be allowed to the indexed
 * property with the given index on the global object.
 */
typedef bool (*IndexedSecurityCallback)(Local<Object> global,
                                        uint32_t index,
                                        AccessType type,
                                        Local<Value> data);


/**
 * A FunctionTemplate is used to create functions at runtime. There
 * can only be one function created from a FunctionTemplate in a
 * context.
 *
 * A FunctionTemplate can have properties, these properties are added to the
 * function object when it is created.
 *
 * A FunctionTemplate has a corresponding instance template which is
 * used to create object instances when the function is used as a
 * constructor. Properties added to the instance template are added to
 * each object instance.
 *
 * A FunctionTemplate can have a prototype template. The prototype template
 * is used to create the prototype object of the function.
 *
 * The following example shows how to use a FunctionTemplate:
 *
 * \code
 *    v8::Local<v8::FunctionTemplate> t = v8::FunctionTemplate::New();
 *    t->Set("func_property", v8::Number::New(1));
 *
 *    v8::Local<v8::Template> proto_t = t->PrototypeTemplate();
 *    proto_t->Set("proto_method", v8::FunctionTemplate::New(InvokeCallback));
 *    proto_t->Set("proto_const", v8::Number::New(2));
 *
 *    v8::Local<v8::ObjectTemplate> instance_t = t->InstanceTemplate();
 *    instance_t->SetAccessor("instance_accessor", InstanceAccessorCallback);
 *    instance_t->SetNamedPropertyHandler(PropertyHandlerCallback, ...);
 *    instance_t->Set("instance_property", Number::New(3));
 *
 *    v8::Local<v8::Function> function = t->GetFunction();
 *    v8::Local<v8::Object> instance = function->NewInstance();
 * \endcode
 *
 * Let's use "function" as the JS variable name of the function object
 * and "instance" for the instance object created above.  The function
 * and the instance will have the following properties:
 *
 * \code
 *   func_property in function == true;
 *   function.func_property == 1;
 *
 *   function.prototype.proto_method() invokes 'InvokeCallback'
 *   function.prototype.proto_const == 2;
 *
 *   instance instanceof function == true;
 *   instance.instance_accessor calls 'InstanceAccessorCallback'
 *   instance.instance_property == 3;
 * \endcode
 *
 * A FunctionTemplate can inherit from another one by calling the
 * FunctionTemplate::Inherit method.  The following graph illustrates
 * the semantics of inheritance:
 *
 * \code
 *   FunctionTemplate Parent  -> Parent() . prototype -> { }
 *     ^                                                  ^
 *     | Inherit(Parent)                                  | .__proto__
 *     |                                                  |
 *   FunctionTemplate Child   -> Child()  . prototype -> { }
 * \endcode
 *
 * A FunctionTemplate 'Child' inherits from 'Parent', the prototype
 * object of the Child() function has __proto__ pointing to the
 * Parent() function's prototype object. An instance of the Child
 * function has all properties on Parent's instance templates.
 *
 * Let Parent be the FunctionTemplate initialized in the previous
 * section and create a Child FunctionTemplate by:
 *
 * \code
 *   Local<FunctionTemplate> parent = t;
 *   Local<FunctionTemplate> child = FunctionTemplate::New();
 *   child->Inherit(parent);
 *
 *   Local<Function> child_function = child->GetFunction();
 *   Local<Object> child_instance = child_function->NewInstance();
 * \endcode
 *
 * The Child function and Child instance will have the following
 * properties:
 *
 * \code
 *   child_func.prototype.__proto__ == function.prototype;
 *   child_instance.instance_accessor calls 'InstanceAccessorCallback'
 *   child_instance.instance_property == 3;
 * \endcode
 */
class EXPORT FunctionTemplate : public Template {
 public:
  /** Creates a function template.*/
  static Local<FunctionTemplate> New(
      InvocationCallback callback = 0,
      Handle<Value> data = Handle<Value>(),
      Handle<Signature> signature = Handle<Signature>());
  /** Returns the unique function instance in the current execution context.*/
  Local<Function> GetFunction();

  /**
   * Set the call-handler callback for a FunctionTemplate.  This
   * callback is called whenever the function created from this
   * FunctionTemplate is called.
   */
  void SetCallHandler(InvocationCallback callback,
                      Handle<Value> data = Handle<Value>());

  /** Get the InstanceTemplate. */
  Local<ObjectTemplate> InstanceTemplate();

  /** Causes the function template to inherit from a parent function template.*/
  void Inherit(Handle<FunctionTemplate> parent);

  /**
   * A PrototypeTemplate is the template used to create the prototype object
   * of the function created by this template.
   */
  Local<ObjectTemplate> PrototypeTemplate();


  /**
   * Set the class name of the FunctionTemplate.  This is used for
   * printing objects created with the function created from the
   * FunctionTemplate as its constructor.
   */
  void SetClassName(Handle<String> name);

  /**
   * Determines whether the __proto__ accessor ignores instances of
   * the function template.  If instances of the function template are
   * ignored, __proto__ skips all instances and instead returns the
   * next object in the prototype chain.
   *
   * Call with a value of true to make the __proto__ accessor ignore
   * instances of the function template.  Call with a value of false
   * to make the __proto__ accessor not ignore instances of the
   * function template.  By default, instances of a function template
   * are not ignored.
   */
  void SetHiddenPrototype(bool value);

  /**
   * Returns true if the given object is an instance of this function
   * template.
   */
  bool HasInstance(Handle<Value> object);

 private:
  FunctionTemplate();
  void AddInstancePropertyAccessor(Handle<String> name,
                                   AccessorGetter getter,
                                   AccessorSetter setter,
                                   Handle<Value> data,
                                   AccessControl settings,
                                   PropertyAttribute attributes);
  void SetNamedInstancePropertyHandler(NamedPropertyGetter getter,
                                       NamedPropertySetter setter,
                                       NamedPropertyQuery query,
                                       NamedPropertyDeleter remover,
                                       NamedPropertyEnumerator enumerator,
                                       Handle<Value> data);
  void SetIndexedInstancePropertyHandler(IndexedPropertyGetter getter,
                                         IndexedPropertySetter setter,
                                         IndexedPropertyQuery query,
                                         IndexedPropertyDeleter remover,
                                         IndexedPropertyEnumerator enumerator,
                                         Handle<Value> data);
  void SetInstanceCallAsFunctionHandler(InvocationCallback callback,
                                        Handle<Value> data);

  friend class Context;
  friend class ObjectTemplate;
};


/**
 * An ObjectTemplate is used to create objects at runtime.
 *
 * Properties added to an ObjectTemplate are added to each object
 * created from the ObjectTemplate.
 */
class EXPORT ObjectTemplate : public Template {
 public:
  /** Creates an ObjectTemplate. */
  static Local<ObjectTemplate> New();

  /** Creates a new instance of this template.*/
  Local<Object> NewInstance();

  /**
   * Sets an accessor on the object template.
   *
   * Whenever the property with the given name is accessed on objects
   * created from this ObjectTemplate the getter and setter callbacks
   * are called instead of getting and setting the property directly
   * on the JavaScript object.
   *
   * \param name The name of the property for which an accessor is added.
   * \param getter The callback to invoke when getting the property.
   * \param setter The callback to invoke when setting the property.
   * \param data A piece of data that will be passed to the getter and setter
   *   callbacks whenever they are invoked.
   * \param settings Access control settings for the accessor. This is a bit
   *   field consisting of one of more of
   *   DEFAULT = 0, ALL_CAN_READ = 1, or ALL_CAN_WRITE = 2.
   *   The default is to not allow cross-context access.
   *   ALL_CAN_READ means that all cross-context reads are allowed.
   *   ALL_CAN_WRITE means that all cross-context writes are allowed.
   *   The combination ALL_CAN_READ | ALL_CAN_WRITE can be used to allow all
   *   cross-context access.
   * \param attribute The attributes of the property for which an accessor
   *   is added.
   */
  void SetAccessor(Handle<String> name,
                   AccessorGetter getter,
                   AccessorSetter setter = 0,
                   Handle<Value> data = Handle<Value>(),
                   AccessControl settings = DEFAULT,
                   PropertyAttribute attribute = None);

  /**
   * Sets a named property handler on the object template.
   *
   * Whenever a named property is accessed on objects created from
   * this object template, the provided callback is invoked instead of
   * accessing the property directly on the JavaScript object.
   *
   * \param getter The callback to invoke when getting a property.
   * \param setter The callback to invoke when setting a property.
   * \param query The callback to invoke to check is an object has a property.
   * \param deleter The callback to invoke when deleting a property.
   * \param enumerator The callback to invoke to enumerate all the named
   *   properties of an object.
   * \param data A piece of data that will be passed to the callbacks
   *   whenever they are invoked.
   */
  void SetNamedPropertyHandler(NamedPropertyGetter getter,
                               NamedPropertySetter setter = 0,
                               NamedPropertyQuery query = 0,
                               NamedPropertyDeleter deleter = 0,
                               NamedPropertyEnumerator enumerator = 0,
                               Handle<Value> data = Handle<Value>());

  /**
   * Sets an indexed property handler on the object template.
   *
   * Whenever an indexed property is accessed on objects created from
   * this object template, the provided callback is invoked instead of
   * accessing the property directly on the JavaScript object.
   *
   * \param getter The callback to invoke when getting a property.
   * \param setter The callback to invoke when setting a property.
   * \param query The callback to invoke to check is an object has a property.
   * \param deleter The callback to invoke when deleting a property.
   * \param enumerator The callback to invoke to enumerate all the indexed
   *   properties of an object.
   * \param data A piece of data that will be passed to the callbacks
   *   whenever they are invoked.
   */
  void SetIndexedPropertyHandler(IndexedPropertyGetter getter,
                                 IndexedPropertySetter setter = 0,
                                 IndexedPropertyQuery query = 0,
                                 IndexedPropertyDeleter deleter = 0,
                                 IndexedPropertyEnumerator enumerator = 0,
                                 Handle<Value> data = Handle<Value>());
  /**
   * Sets the callback to be used when calling instances created from
   * this template as a function.  If no callback is set, instances
   * behave like normal JavaScript objects that cannot be called as a
   * function.
   */
  void SetCallAsFunctionHandler(InvocationCallback callback,
                                Handle<Value> data = Handle<Value>());

  /**
   * Mark object instances of the template as undetectable.
   *
   * In many ways, undetectable objects behave as though they are not
   * there.  They behave like 'undefined' in conditionals and when
   * printed.  However, properties can be accessed and called as on
   * normal objects.
   */
  void MarkAsUndetectable();

  /**
   * Sets access check callbacks on the object template.
   *
   * When accessing properties on instances of this object template,
   * the access check callback will be called to determine whether or
   * not to allow cross-context access to the properties.
   */
  void SetAccessCheckCallbacks(NamedSecurityCallback named_handler,
                               IndexedSecurityCallback indexed_handler,
                               Handle<Value> data = Handle<Value>());

  /**
   * Gets the number of internal fields for objects generated from
   * this template.
   */
  int InternalFieldCount();

  /**
   * Sets the number of internal fields for objects generated from
   * this template.
   */
  void SetInternalFieldCount(int value);

 private:
  ObjectTemplate();
  static Local<ObjectTemplate> New(Handle<FunctionTemplate> constructor);
  friend class FunctionTemplate;
};


/**
 * A Signature specifies which receivers and arguments a function can
 * legally be called with.
 */
class EXPORT Signature : public Data {
 public:
  static Local<Signature> New(Handle<FunctionTemplate> receiver =
                                  Handle<FunctionTemplate>(),
                              int argc = 0,
                              Handle<FunctionTemplate> argv[] = 0);
 private:
  Signature();
};


/**
 * A utility for determining the type of objects based on the template
 * they were constructed from.
 */
class EXPORT TypeSwitch : public Data {
 public:
  static Local<TypeSwitch> New(Handle<FunctionTemplate> type);
  static Local<TypeSwitch> New(int argc, Handle<FunctionTemplate> types[]);
  int match(Handle<Value> value);
 private:
  TypeSwitch();
};


// --- E x t e n s i o n s ---


/**
 * Ignore
 */
class EXPORT Extension {  // NOLINT
 public:
  Extension(const char* name,
            const char* source = 0,
            int dep_count = 0,
            const char** deps = 0);
  virtual ~Extension() { }
  virtual v8::Handle<v8::FunctionTemplate>
      GetNativeFunction(v8::Handle<v8::String> name) {
    return v8::Handle<v8::FunctionTemplate>();
  }

  const char* name() { return name_; }
  const char* source() { return source_; }
  int dependency_count() { return dep_count_; }
  const char** dependencies() { return deps_; }
  void set_auto_enable(bool value) { auto_enable_ = value; }
  bool auto_enable() { return auto_enable_; }

 private:
  const char* name_;
  const char* source_;
  int dep_count_;
  const char** deps_;
  bool auto_enable_;
};


void EXPORT RegisterExtension(Extension* extension);


/**