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-rw-r--r--js/src/vm/StringObject.h74
1 files changed, 74 insertions, 0 deletions
diff --git a/js/src/vm/StringObject.h b/js/src/vm/StringObject.h
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+/* -*- 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 NativeObject
+{
+ 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,
+ HandleObject proto = nullptr,
+ NewObjectKind newKind = GenericObject);
+
+ /*
+ * 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);
+
+ 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) {
+ MOZ_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, HandleObject global);
+};
+
+} // namespace js
+
+#endif /* vm_StringObject_h */