1 files changed, 46 insertions, 0 deletions
diff --git a/dom/canvas/CacheInvalidator.cpp b/dom/canvas/CacheInvalidator.cpp
new file mode 100644
index 0000000000..c796cfce6b
--- /dev/null
+++ b/dom/canvas/CacheInvalidator.cpp
@@ -0,0 +1,46 @@
+/* -*- Mode: C++; tab-width: 13; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=13 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 "CacheInvalidator.h"
+
+namespace mozilla {
+
+void CacheInvalidator::InvalidateCaches() const {
+  // The only sane approach is to require caches to remove invalidators.
+  while (!mCaches.empty()) {
+    const auto& itr = mCaches.begin();
+    const auto pEntry = *itr;
+    pEntry->OnInvalidate();
+    MOZ_ASSERT(mCaches.find(pEntry) == mCaches.end());
+  }
+}
+
+// -
+
+void AbstractCache::ResetInvalidators(InvalidatorListT&& newList) {
+  for (const auto& cur : mInvalidators) {
+    if (cur) {
+      (void)cur->mCaches.erase(this);
+    }
+  }
+
+  mInvalidators = std::move(newList);
+
+  for (const auto& cur : mInvalidators) {
+    // Don't assert that we insert, since there may be dupes in `invalidators`.
+    // (and it's not worth removing the dupes)
+    if (cur) {
+      (void)cur->mCaches.insert(this);
+    }
+  }
+}
+
+void AbstractCache::AddInvalidator(const CacheInvalidator& x) {
+  mInvalidators.push_back(&x);
+  x.mCaches.insert(this);
+}
+
+}  // namespace mozilla