1 files changed, 131 insertions, 0 deletions
diff --git a/dom/svg/SVGTransformList.h b/dom/svg/SVGTransformList.h
new file mode 100644
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+++ b/dom/svg/SVGTransformList.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 DOM_SVG_SVGTRANSFORMLIST_H_
+#define DOM_SVG_SVGTRANSFORMLIST_H_
+
+#include "gfxMatrix.h"
+#include "SVGTransform.h"
+#include "nsTArray.h"
+
+namespace mozilla {
+
+namespace dom {
+class DOMSVGTransform;
+class DOMSVGTransformList;
+}  // namespace dom
+
+/**
+ * ATTENTION! WARNING! WATCH OUT!!
+ *
+ * Consumers that modify objects of this type absolutely MUST keep the DOM
+ * wrappers for those lists (if any) in sync!! That's why this class is so
+ * locked down.
+ *
+ * The DOM wrapper class for this class is DOMSVGTransformList.
+ */
+class SVGTransformList {
+  friend class SVGAnimatedTransformList;
+  friend class dom::DOMSVGTransform;
+  friend class dom::DOMSVGTransformList;
+
+ public:
+  SVGTransformList() = default;
+  ~SVGTransformList() = default;
+
+  // Only methods that don't make/permit modification to this list are public.
+  // Only our friend classes can access methods that may change us.
+
+  /// This may return an incomplete string on OOM, but that's acceptable.
+  void GetValueAsString(nsAString& aValue) const;
+
+  bool IsEmpty() const { return mItems.IsEmpty(); }
+
+  uint32_t Length() const { return mItems.Length(); }
+
+  const SVGTransform& operator[](uint32_t aIndex) const {
+    return mItems[aIndex];
+  }
+
+  bool operator==(const SVGTransformList& rhs) const {
+    return mItems == rhs.mItems;
+  }
+
+  bool SetCapacity(uint32_t size) { return mItems.SetCapacity(size, fallible); }
+
+  void Compact() { mItems.Compact(); }
+
+  gfxMatrix GetConsolidationMatrix() const;
+
+  // Access to methods that can modify objects of this type is deliberately
+  // limited. This is to reduce the chances of someone modifying objects of
+  // this type without taking the necessary steps to keep DOM wrappers in sync.
+  // If you need wider access to these methods, consider adding a method to
+  // DOMSVGAnimatedTransformList and having that class act as an intermediary so
+  // it can take care of keeping DOM wrappers in sync.
+
+ protected:
+  /**
+   * These may fail on OOM if the internal capacity needs to be increased, in
+   * which case the list will be left unmodified.
+   */
+  nsresult CopyFrom(const SVGTransformList& rhs);
+  nsresult CopyFrom(const nsTArray<SVGTransform>& aTransformArray);
+
+  SVGTransform& operator[](uint32_t aIndex) { return mItems[aIndex]; }
+
+  /**
+   * This may fail (return false) on OOM if the internal capacity is being
+   * increased, in which case the list will be left unmodified.
+   */
+  bool SetLength(uint32_t aNumberOfItems) {
+    return mItems.SetLength(aNumberOfItems, fallible);
+  }
+
+ private:
+  // Marking the following private only serves to show which methods are only
+  // used by our friend classes (as opposed to our subclasses) - it doesn't
+  // really provide additional safety.
+
+  nsresult SetValueFromString(const nsAString& aValue);
+
+  void Clear() { mItems.Clear(); }
+
+  bool InsertItem(uint32_t aIndex, const SVGTransform& aTransform) {
+    if (aIndex >= mItems.Length()) {
+      aIndex = mItems.Length();
+    }
+    return !!mItems.InsertElementAt(aIndex, aTransform, fallible);
+  }
+
+  void ReplaceItem(uint32_t aIndex, const SVGTransform& aTransform) {
+    MOZ_ASSERT(aIndex < mItems.Length(),
+               "DOM wrapper caller should have raised INDEX_SIZE_ERR");
+    mItems[aIndex] = aTransform;
+  }
+
+  void RemoveItem(uint32_t aIndex) {
+    MOZ_ASSERT(aIndex < mItems.Length(),
+               "DOM wrapper caller should have raised INDEX_SIZE_ERR");
+    mItems.RemoveElementAt(aIndex);
+  }
+
+  bool AppendItem(const SVGTransform& aTransform) {
+    return !!mItems.AppendElement(aTransform, fallible);
+  }
+
+ protected:
+  /*
+   * See SVGLengthList for the rationale for using
+   * FallibleTArray<SVGTransform> instead of FallibleTArray<SVGTransform,
+   * 1>.
+   */
+  FallibleTArray<SVGTransform> mItems;
+};
+
+}  // namespace mozilla
+
+#endif  // DOM_SVG_SVGTRANSFORMLIST_H_