runtime/JSArrayIterator.h

   1 /*
   2  * Copyright (C) 2013 Apple, Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef JSArrayIterator_h
  27 #define JSArrayIterator_h
  28
  29 #include "JSObject.h"
  30
  31 namespace JSC {
  32
  33 enum ArrayIterationKind : uint32_t {
  34     ArrayIterateKey,
  35     ArrayIterateValue,
  36     ArrayIterateKeyValue,
  37     ArrayIterateSparseTag = 4,
  38     ArrayIterateSparseKey,
  39     ArrayIterateSparseValue,
  40     ArrayIterateSparseKeyValue
  41 };
  42
  43 class JSArrayIterator : public JSNonFinalObject {
  44 public:
  45     typedef JSNonFinalObject Base;
  46
  47     DECLARE_EXPORT_INFO;
  48
  49     static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
  50     {
  51         return Structure::create(vm, globalObject, prototype, TypeInfo(ObjectType, StructureFlags), info());
  52     }
  53
  54     static JSArrayIterator* create(ExecState* exec, Structure* structure, ArrayIterationKind kind, JSObject* iteratedObject)
  55     {
  56         VM& vm = exec->vm();
  57         JSArrayIterator* instance = new (NotNull, allocateCell<JSArrayIterator>(vm.heap)) JSArrayIterator(vm, structure);
  58         instance->finishCreation(vm, structure->globalObject(), kind, iteratedObject);
  59         return instance;
  60     }
  61
  62     ArrayIterationKind iterationKind() const { return m_iterationKind; }
  63     JSObject* iteratedObject() const { return m_iteratedObject.get(); }
  64     size_t nextIndex() const { return m_nextIndex; }
  65     void setNextIndex(size_t nextIndex) { m_nextIndex = nextIndex; }
  66     void finish() { m_nextIndex = std::numeric_limits<uint32_t>::max(); }
  67
  68     using JSNonFinalObject::arrayStorageOrNull;
  69     static ptrdiff_t offsetOfIterationKind() { return OBJECT_OFFSETOF(JSArrayIterator, m_iterationKind); }
  70     static ptrdiff_t offsetOfIteratedObject() { return OBJECT_OFFSETOF(JSArrayIterator, m_iteratedObject); }
  71     static ptrdiff_t offsetOfNextIndex() { return OBJECT_OFFSETOF(JSArrayIterator, m_nextIndex); }
  72
  73 private:
  74
  75     static const unsigned StructureFlags = Base::StructureFlags | OverridesVisitChildren;
  76
  77     JSArrayIterator(VM& vm, Structure* structure)
  78         : Base(vm, structure)
  79         , m_nextIndex(0)
  80     {
  81     }
  82
  83     void finishCreation(VM&, JSGlobalObject*, ArrayIterationKind, JSObject* iteratedObject);
  84     static void visitChildren(JSCell*, SlotVisitor&);
  85
  86     ArrayIterationKind m_iterationKind;
  87     WriteBarrier<JSObject> m_iteratedObject;
  88     uint32_t m_nextIndex;
  89 };
  90
  91 }
  92
  93 #endif // !defined(JSArrayIterator_h)