discardable_memory: Using mojo IPC to replace Chrome IPC

components/discardable_memory/client/client_discardable_shared_memory_manager.h

 // Copyright 2014 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.
 
 #ifndef COMPONENTS_DISCARDABLE_MEMORY_CLIENT_CLIENT_DISCARDABLE_SHARED_MEMORY_MANAGER_H_
 #define COMPONENTS_DISCARDABLE_MEMORY_CLIENT_CLIENT_DISCARDABLE_SHARED_MEMORY_MANAGER_H_
 
 #include <stddef.h>
 
+#include "base/callback_helpers.h"
 #include "base/macros.h"
 #include "base/memory/discardable_memory_allocator.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/shared_memory_handle.h"
 #include "base/synchronization/lock.h"
 #include "base/trace_event/memory_dump_provider.h"
 #include "components/discardable_memory/common/discardable_memory_export.h"
 #include "components/discardable_memory/common/discardable_shared_memory_heap.h"
-#include "components/discardable_memory/common/discardable_shared_memory_id.h"
+#include "components/discardable_memory/public/interfaces/discardable_shared_memory_manager.mojom.h"
+
+namespace base {
+class SingleThreadTaskRunner;
+}
 
 namespace discardable_memory {
 
 // Implementation of DiscardableMemoryAllocator that allocates
 // discardable memory segments through the browser process.
 class DISCARDABLE_MEMORY_EXPORT ClientDiscardableSharedMemoryManager
     : public base::DiscardableMemoryAllocator,
       public base::trace_event::MemoryDumpProvider {
  public:
-  class Delegate {
-   public:
-    virtual void AllocateLockedDiscardableSharedMemory(
-        size_t size,
-        DiscardableSharedMemoryId id,
-        base::SharedMemoryHandle* handle) = 0;
-    virtual void DeletedDiscardableSharedMemory(
-        DiscardableSharedMemoryId id) = 0;
-
-   protected:
-    virtual ~Delegate() {}
-  };
-
-  explicit ClientDiscardableSharedMemoryManager(Delegate* delegate);
+  ClientDiscardableSharedMemoryManager(
+      mojom::DiscardableSharedMemoryManagerPtr manager,
+      scoped_refptr<base::SingleThreadTaskRunner> io_task_runner);
   ~ClientDiscardableSharedMemoryManager() override;
 
   // Overridden from base::DiscardableMemoryAllocator:
   std::unique_ptr<base::DiscardableMemory> AllocateLockedDiscardableMemory(
       size_t size) override;
 
   // Overridden from base::trace_event::MemoryDumpProvider:
   bool OnMemoryDump(const base::trace_event::MemoryDumpArgs& args,
                     base::trace_event::ProcessMemoryDump* pmd) override;
 
@@ skipping 11 matching lines @@
 
   struct Statistics {
     size_t total_size;
     size_t freelist_size;
   };
 
   Statistics GetStatistics() const;
 
  private:
   std::unique_ptr<base::DiscardableSharedMemory>
-  AllocateLockedDiscardableSharedMemory(size_t size,
-                                        DiscardableSharedMemoryId id);
+  AllocateLockedDiscardableSharedMemory(size_t size, int32_t id);
+  void AllocateOnIO(size_t size,
+                    int32_t id,
+                    std::unique_ptr<base::DiscardableSharedMemory>* memory,
+                    base::ScopedClosureRunner closure_runner);
+  void AllocateCompletedOnIO(
+      std::unique_ptr<base::DiscardableSharedMemory>* memory,
+      base::ScopedClosureRunner closure_runner,
+      mojo::ScopedSharedBufferHandle mojo_handle);
+
+  void DeletedDiscardableSharedMemory(int32_t id);
   void MemoryUsageChanged(size_t new_bytes_allocated,
                           size_t new_bytes_free) const;
 
+  scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
+  // TODO(penghuang): Switch to ThreadSafeInterfacePtr when it starts supporting
+  // sync method call.
+  std::unique_ptr<mojom::DiscardableSharedMemoryManagerPtr> manager_mojo_;
+
   mutable base::Lock lock_;
-  DiscardableSharedMemoryHeap heap_;
-  Delegate* const delegate_;
+  std::unique_ptr<DiscardableSharedMemoryHeap> heap_;
 
   DISALLOW_COPY_AND_ASSIGN(ClientDiscardableSharedMemoryManager);
 };
 
 }  // namespace discardable_memory
 
 #endif  // COMPONENTS_DISCARDABLE_MEMORY_CLIENT_CLIENT_DISCARDABLE_SHARED_MEMORY_MANAGER_H_