Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 194 insertions, 0 deletions

diff --git a/security/sandbox/chromium/base/callback_internal.h b/security/sandbox/chromium/base/callback_internal.h
new file mode 100644
index 0000000000..fdfdf7f817
--- /dev/null
+++ b/security/sandbox/chromium/base/callback_internal.h
@@ -0,0 +1,194 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// This file contains utility functions and classes that help the
+// implementation, and management of the Callback objects.
+
+#ifndef BASE_CALLBACK_INTERNAL_H_
+#define BASE_CALLBACK_INTERNAL_H_
+
+#include "base/base_export.h"
+#include "base/callback_forward.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+
+namespace base {
+
+struct FakeBindState;
+
+namespace internal {
+
+class BindStateBase;
+class FinallyExecutorCommon;
+class ThenAndCatchExecutorCommon;
+
+template <typename ReturnType>
+class PostTaskExecutor;
+
+template <typename Functor, typename... BoundArgs>
+struct BindState;
+
+class CallbackBase;
+class CallbackBaseCopyable;
+
+struct BindStateBaseRefCountTraits {
+  static void Destruct(const BindStateBase*);
+};
+
+template <typename T>
+using PassingType = std::conditional_t<std::is_scalar<T>::value, T, T&&>;
+
+// BindStateBase is used to provide an opaque handle that the Callback
+// class can use to represent a function object with bound arguments.  It
+// behaves as an existential type that is used by a corresponding
+// DoInvoke function to perform the function execution.  This allows
+// us to shield the Callback class from the types of the bound argument via
+// "type erasure."
+// At the base level, the only task is to add reference counting data. Avoid
+// using or inheriting any virtual functions. Creating a vtable for every
+// BindState template instantiation results in a lot of bloat. Its only task is
+// to call the destructor which can be done with a function pointer.
+class BASE_EXPORT BindStateBase
+    : public RefCountedThreadSafe<BindStateBase, BindStateBaseRefCountTraits> {
+ public:
+  REQUIRE_ADOPTION_FOR_REFCOUNTED_TYPE();
+
+  enum CancellationQueryMode {
+    IS_CANCELLED,
+    MAYBE_VALID,
+  };
+
+  using InvokeFuncStorage = void(*)();
+
+ private:
+  BindStateBase(InvokeFuncStorage polymorphic_invoke,
+                void (*destructor)(const BindStateBase*));
+  BindStateBase(InvokeFuncStorage polymorphic_invoke,
+                void (*destructor)(const BindStateBase*),
+                bool (*query_cancellation_traits)(const BindStateBase*,
+                                                  CancellationQueryMode mode));
+
+  ~BindStateBase() = default;
+
+  friend struct BindStateBaseRefCountTraits;
+  friend class RefCountedThreadSafe<BindStateBase, BindStateBaseRefCountTraits>;
+
+  friend class CallbackBase;
+  friend class CallbackBaseCopyable;
+
+  // Whitelist subclasses that access the destructor of BindStateBase.
+  template <typename Functor, typename... BoundArgs>
+  friend struct BindState;
+  friend struct ::base::FakeBindState;
+
+  bool IsCancelled() const {
+    return query_cancellation_traits_(this, IS_CANCELLED);
+  }
+
+  bool MaybeValid() const {
+    return query_cancellation_traits_(this, MAYBE_VALID);
+  }
+
+  // In C++, it is safe to cast function pointers to function pointers of
+  // another type. It is not okay to use void*. We create a InvokeFuncStorage
+  // that that can store our function pointer, and then cast it back to
+  // the original type on usage.
+  InvokeFuncStorage polymorphic_invoke_;
+
+  // Pointer to a function that will properly destroy |this|.
+  void (*destructor_)(const BindStateBase*);
+  bool (*query_cancellation_traits_)(const BindStateBase*,
+                                     CancellationQueryMode mode);
+
+  DISALLOW_COPY_AND_ASSIGN(BindStateBase);
+};
+
+// Holds the Callback methods that don't require specialization to reduce
+// template bloat.
+// CallbackBase<MoveOnly> is a direct base class of MoveOnly callbacks, and
+// CallbackBase<Copyable> uses CallbackBase<MoveOnly> for its implementation.
+class BASE_EXPORT CallbackBase {
+ public:
+  inline CallbackBase(CallbackBase&& c) noexcept;
+  CallbackBase& operator=(CallbackBase&& c) noexcept;
+
+  explicit CallbackBase(const CallbackBaseCopyable& c);
+  CallbackBase& operator=(const CallbackBaseCopyable& c);
+
+  explicit CallbackBase(CallbackBaseCopyable&& c) noexcept;
+  CallbackBase& operator=(CallbackBaseCopyable&& c) noexcept;
+
+  // Returns true if Callback is null (doesn't refer to anything).
+  bool is_null() const { return !bind_state_; }
+  explicit operator bool() const { return !is_null(); }
+
+  // Returns true if the callback invocation will be nop due to an cancellation.
+  // It's invalid to call this on uninitialized callback.
+  //
+  // Must be called on the Callback's destination sequence.
+  bool IsCancelled() const;
+
+  // If this returns false, the callback invocation will be a nop due to a
+  // cancellation. This may(!) still return true, even on a cancelled callback.
+  //
+  // This function is thread-safe.
+  bool MaybeValid() const;
+
+  // Returns the Callback into an uninitialized state.
+  void Reset();
+
+ protected:
+  friend class FinallyExecutorCommon;
+  friend class ThenAndCatchExecutorCommon;
+
+  template <typename ReturnType>
+  friend class PostTaskExecutor;
+
+  using InvokeFuncStorage = BindStateBase::InvokeFuncStorage;
+
+  // Returns true if this callback equals |other|. |other| may be null.
+  bool EqualsInternal(const CallbackBase& other) const;
+
+  constexpr inline CallbackBase();
+
+  // Allow initializing of |bind_state_| via the constructor to avoid default
+  // initialization of the scoped_refptr.
+  explicit inline CallbackBase(BindStateBase* bind_state);
+
+  InvokeFuncStorage polymorphic_invoke() const {
+    return bind_state_->polymorphic_invoke_;
+  }
+
+  // Force the destructor to be instantiated inside this translation unit so
+  // that our subclasses will not get inlined versions.  Avoids more template
+  // bloat.
+  ~CallbackBase();
+
+  scoped_refptr<BindStateBase> bind_state_;
+};
+
+constexpr CallbackBase::CallbackBase() = default;
+CallbackBase::CallbackBase(CallbackBase&&) noexcept = default;
+CallbackBase::CallbackBase(BindStateBase* bind_state)
+    : bind_state_(AdoptRef(bind_state)) {}
+
+// CallbackBase<Copyable> is a direct base class of Copyable Callbacks.
+class BASE_EXPORT CallbackBaseCopyable : public CallbackBase {
+ public:
+  CallbackBaseCopyable(const CallbackBaseCopyable& c);
+  CallbackBaseCopyable(CallbackBaseCopyable&& c) noexcept = default;
+  CallbackBaseCopyable& operator=(const CallbackBaseCopyable& c);
+  CallbackBaseCopyable& operator=(CallbackBaseCopyable&& c) noexcept;
+
+ protected:
+  constexpr CallbackBaseCopyable() = default;
+  explicit CallbackBaseCopyable(BindStateBase* bind_state)
+      : CallbackBase(bind_state) {}
+  ~CallbackBaseCopyable() = default;
+};
+
+}  // namespace internal
+}  // namespace base
+
+#endif  // BASE_CALLBACK_INTERNAL_H_