1 files changed, 252 insertions, 0 deletions
diff --git a/xpcom/ds/nsCOMArray.cpp b/xpcom/ds/nsCOMArray.cpp
new file mode 100644
index 0000000000..d388857573
--- /dev/null
+++ b/xpcom/ds/nsCOMArray.cpp
@@ -0,0 +1,252 @@
+/* -*- 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/. */
+
+#include "nsCOMArray.h"
+
+#include "mozilla/MemoryReporting.h"
+#include "mozilla/OperatorNewExtensions.h"
+#include "nsQuickSort.h"
+
+#include "nsCOMPtr.h"
+
+// This specialization is private to nsCOMArray.
+// It exists solely to automatically zero-out newly created array elements.
+template <>
+class nsTArrayElementTraits<nsISupports*> {
+  typedef nsISupports* E;
+
+ public:
+  // Zero out the value
+  static inline void Construct(E* aE) {
+    new (mozilla::KnownNotNull, static_cast<void*>(aE)) E();
+  }
+  // Invoke the copy-constructor in place.
+  template <class A>
+  static inline void Construct(E* aE, const A& aArg) {
+    new (mozilla::KnownNotNull, static_cast<void*>(aE)) E(aArg);
+  }
+  // Construct in place.
+  template <class... Args>
+  static inline void Emplace(E* aE, Args&&... aArgs) {
+    new (mozilla::KnownNotNull, static_cast<void*>(aE))
+        E(std::forward<Args>(aArgs)...);
+  }
+  // Invoke the destructor in place.
+  static inline void Destruct(E* aE) { aE->~E(); }
+};
+
+static void ReleaseObjects(nsTArray<nsISupports*>& aArray);
+
+// implementations of non-trivial methods in nsCOMArray_base
+
+nsCOMArray_base::nsCOMArray_base(const nsCOMArray_base& aOther) {
+  // make sure we do only one allocation
+  mArray.SetCapacity(aOther.Count());
+  AppendObjects(aOther);
+}
+
+nsCOMArray_base::~nsCOMArray_base() { Clear(); }
+
+int32_t nsCOMArray_base::IndexOf(nsISupports* aObject,
+                                 uint32_t aStartIndex) const {
+  return mArray.IndexOf(aObject, aStartIndex);
+}
+
+int32_t nsCOMArray_base::IndexOfObject(nsISupports* aObject) const {
+  nsCOMPtr<nsISupports> supports = do_QueryInterface(aObject);
+  if (NS_WARN_IF(!supports)) {
+    return -1;
+  }
+
+  uint32_t i, count;
+  int32_t retval = -1;
+  count = mArray.Length();
+  for (i = 0; i < count; ++i) {
+    nsCOMPtr<nsISupports> arrayItem = do_QueryInterface(mArray[i]);
+    if (arrayItem == supports) {
+      retval = i;
+      break;
+    }
+  }
+  return retval;
+}
+
+bool nsCOMArray_base::EnumerateForwards(nsBaseArrayEnumFunc aFunc,
+                                        void* aData) const {
+  for (uint32_t index = 0; index < mArray.Length(); ++index) {
+    if (!(*aFunc)(mArray[index], aData)) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+bool nsCOMArray_base::EnumerateBackwards(nsBaseArrayEnumFunc aFunc,
+                                         void* aData) const {
+  for (uint32_t index = mArray.Length(); index--;) {
+    if (!(*aFunc)(mArray[index], aData)) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+int nsCOMArray_base::VoidStarComparator(const void* aElement1,
+                                        const void* aElement2, void* aData) {
+  auto ctx = static_cast<nsISupportsComparatorContext*>(aData);
+  return (*ctx->mComparatorFunc)(*static_cast<nsISupports* const*>(aElement1),
+                                 *static_cast<nsISupports* const*>(aElement2),
+                                 ctx->mData);
+}
+
+void nsCOMArray_base::Sort(nsISupportsComparatorFunc aFunc, void* aData) {
+  if (mArray.Length() > 1) {
+    nsISupportsComparatorContext ctx = {aFunc, aData};
+    NS_QuickSort(mArray.Elements(), mArray.Length(), sizeof(nsISupports*),
+                 VoidStarComparator, &ctx);
+  }
+}
+
+bool nsCOMArray_base::InsertObjectAt(nsISupports* aObject, int32_t aIndex) {
+  if ((uint32_t)aIndex > mArray.Length()) {
+    return false;
+  }
+
+  mArray.InsertElementAt(aIndex, aObject);
+
+  NS_IF_ADDREF(aObject);
+  return true;
+}
+
+void nsCOMArray_base::InsertElementAt(uint32_t aIndex, nsISupports* aElement) {
+  mArray.InsertElementAt(aIndex, aElement);
+  NS_IF_ADDREF(aElement);
+}
+
+void nsCOMArray_base::InsertElementAt(uint32_t aIndex,
+                                      already_AddRefed<nsISupports> aElement) {
+  mArray.InsertElementAt(aIndex, aElement.take());
+}
+
+bool nsCOMArray_base::InsertObjectsAt(const nsCOMArray_base& aObjects,
+                                      int32_t aIndex) {
+  if ((uint32_t)aIndex > mArray.Length()) {
+    return false;
+  }
+
+  mArray.InsertElementsAt(aIndex, aObjects.mArray);
+
+  // need to addref all these
+  uint32_t count = aObjects.Length();
+  for (uint32_t i = 0; i < count; ++i) {
+    NS_IF_ADDREF(aObjects[i]);
+  }
+
+  return true;
+}
+
+void nsCOMArray_base::InsertElementsAt(uint32_t aIndex,
+                                       const nsCOMArray_base& aElements) {
+  mArray.InsertElementsAt(aIndex, aElements.mArray);
+
+  // need to addref all these
+  uint32_t count = aElements.Length();
+  for (uint32_t i = 0; i < count; ++i) {
+    NS_IF_ADDREF(aElements[i]);
+  }
+}
+
+void nsCOMArray_base::InsertElementsAt(uint32_t aIndex,
+                                       nsISupports* const* aElements,
+                                       uint32_t aCount) {
+  mArray.InsertElementsAt(aIndex, aElements, aCount);
+
+  // need to addref all these
+  for (uint32_t i = 0; i < aCount; ++i) {
+    NS_IF_ADDREF(aElements[i]);
+  }
+}
+
+void nsCOMArray_base::ReplaceObjectAt(nsISupports* aObject, int32_t aIndex) {
+  mArray.EnsureLengthAtLeast(aIndex + 1);
+  nsISupports* oldObject = mArray[aIndex];
+  // Make sure to addref first, in case aObject == oldObject
+  NS_IF_ADDREF(mArray[aIndex] = aObject);
+  NS_IF_RELEASE(oldObject);
+}
+
+bool nsCOMArray_base::RemoveObject(nsISupports* aObject) {
+  bool result = mArray.RemoveElement(aObject);
+  if (result) {
+    NS_IF_RELEASE(aObject);
+  }
+  return result;
+}
+
+bool nsCOMArray_base::RemoveObjectAt(int32_t aIndex) {
+  if (uint32_t(aIndex) < mArray.Length()) {
+    nsISupports* element = mArray[aIndex];
+
+    mArray.RemoveElementAt(aIndex);
+    NS_IF_RELEASE(element);
+    return true;
+  }
+
+  return false;
+}
+
+void nsCOMArray_base::RemoveElementAt(uint32_t aIndex) {
+  nsISupports* element = mArray[aIndex];
+  mArray.RemoveElementAt(aIndex);
+  NS_IF_RELEASE(element);
+}
+
+bool nsCOMArray_base::RemoveObjectsAt(int32_t aIndex, int32_t aCount) {
+  if (uint32_t(aIndex) + uint32_t(aCount) <= mArray.Length()) {
+    nsTArray<nsISupports*> elementsToDestroy(aCount);
+    elementsToDestroy.AppendElements(mArray.Elements() + aIndex, aCount);
+    mArray.RemoveElementsAt(aIndex, aCount);
+    ReleaseObjects(elementsToDestroy);
+    return true;
+  }
+
+  return false;
+}
+
+void nsCOMArray_base::RemoveElementsAt(uint32_t aIndex, uint32_t aCount) {
+  nsTArray<nsISupports*> elementsToDestroy(aCount);
+  elementsToDestroy.AppendElements(mArray.Elements() + aIndex, aCount);
+  mArray.RemoveElementsAt(aIndex, aCount);
+  ReleaseObjects(elementsToDestroy);
+}
+
+// useful for destructors
+void ReleaseObjects(nsTArray<nsISupports*>& aArray) {
+  for (uint32_t i = 0; i < aArray.Length(); ++i) {
+    NS_IF_RELEASE(aArray[i]);
+  }
+}
+
+void nsCOMArray_base::Clear() {
+  nsTArray<nsISupports*> objects = std::move(mArray);
+  ReleaseObjects(objects);
+}
+
+bool nsCOMArray_base::SetCount(int32_t aNewCount) {
+  NS_ASSERTION(aNewCount >= 0, "SetCount(negative index)");
+  if (aNewCount < 0) {
+    return false;
+  }
+
+  int32_t count = mArray.Length();
+  if (count > aNewCount) {
+    RemoveObjectsAt(aNewCount, mArray.Length() - aNewCount);
+  }
+  mArray.SetLength(aNewCount);
+  return true;
+}