text: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
   * vim: set ts=8 sts=4 et sw=4 tw=99:
   * This Source Code Form is subject to the terms of the Mozilla Public
   * License, v. 2.0. If a copy of the MPL was not distributed with this
   * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
  
  #ifndef vm_StringObject_h
  #define vm_StringObject_h
  
  #include "jsobj.h"
  #include "jsstr.h"
  
  #include "vm/Shape.h"
  
  namespace js {
  
  class StringObject : public JSObject
  {
      static const unsigned PRIMITIVE_VALUE_SLOT = 0;
      static const unsigned LENGTH_SLOT = 1;
  
    public:
      static const unsigned RESERVED_SLOTS = 2;
  
      static const Class class_;
  
      /*
       * Creates a new String object boxing the given string.  The object's
       * [[Prototype]] is determined from context.
       */
      static inline StringObject *create(JSContext *cx, HandleString str,
                                         NewObjectKind newKind = GenericObject);
  
      JSString *unbox() const {
          return getFixedSlot(PRIMITIVE_VALUE_SLOT).toString();
      }
  
      inline size_t length() const {
          return size_t(getFixedSlot(LENGTH_SLOT).toInt32());
      }
  
      static size_t offsetOfPrimitiveValue() {
          return getFixedSlotOffset(PRIMITIVE_VALUE_SLOT);
      }
      static size_t offsetOfLength() {
          return getFixedSlotOffset(LENGTH_SLOT);
      }
  
    private:
      inline bool init(JSContext *cx, HandleString str);
  
      void setStringThis(JSString *str) {
          JS_ASSERT(getReservedSlot(PRIMITIVE_VALUE_SLOT).isUndefined());
          setFixedSlot(PRIMITIVE_VALUE_SLOT, StringValue(str));
          setFixedSlot(LENGTH_SLOT, Int32Value(int32_t(str->length())));
      }
  
      /* For access to init, as String.prototype is special. */
      friend JSObject *
      ::js_InitStringClass(JSContext *cx, js::HandleObject global);
  
      /* For access to assignInitialShape. */
      friend bool
      EmptyShape::ensureInitialCustomShape<StringObject>(ExclusiveContext *cx,
                                                         Handle<StringObject*> obj);
  
      /*
       * Compute the initial shape to associate with fresh String objects, which
       * encodes the initial length property. Return the shape after changing
       * |obj|'s last property to it.
       */
      static Shape *
      assignInitialShape(ExclusiveContext *cx, Handle<StringObject*> obj);
  };
  
  } // namespace js
  
  #endif /* vm_StringObject_h */
  