1 files changed, 47 insertions, 0 deletions
diff --git a/chromium/v8/src/heap/cppgc/task-handle.h b/chromium/v8/src/heap/cppgc/task-handle.h
new file mode 100644
index 00000000000..cbd8cc4a61f
--- /dev/null
+++ b/chromium/v8/src/heap/cppgc/task-handle.h
@@ -0,0 +1,47 @@
+// Copyright 2020 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef V8_HEAP_CPPGC_TASK_HANDLE_H_
+#define V8_HEAP_CPPGC_TASK_HANDLE_H_
+
+#include <memory>
+
+#include "src/base/logging.h"
+
+namespace cppgc {
+namespace internal {
+
+// A handle that is used for cancelling individual tasks.
+struct SingleThreadedHandle {
+  struct NonEmptyTag {};
+
+  // Default construction results in empty handle.
+  SingleThreadedHandle() = default;
+
+  explicit SingleThreadedHandle(NonEmptyTag)
+      : is_cancelled_(std::make_shared<bool>(false)) {}
+
+  void Cancel() {
+    DCHECK(is_cancelled_);
+    *is_cancelled_ = true;
+  }
+
+  bool IsCanceled() const {
+    DCHECK(is_cancelled_);
+    return *is_cancelled_;
+  }
+
+  // A handle is active if it is non-empty and not cancelled.
+  explicit operator bool() const {
+    return is_cancelled_.get() && !*is_cancelled_.get();
+  }
+
+ private:
+  std::shared_ptr<bool> is_cancelled_;
+};
+
+}  // namespace internal
+}  // namespace cppgc
+
+#endif  // V8_HEAP_CPPGC_TASK_HANDLE_H_