content: Pass IOSurface references using Mach IPC.

content/browser/browser_io_surface_manager_mac.h

+// Copyright 2015 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 CONTENT_BROWSER_BROWSER_IO_SURFACE_MANAGER_MAC_H_
+#define CONTENT_BROWSER_BROWSER_IO_SURFACE_MANAGER_MAC_H_
+
+#include <mach/mach.h>
+
+#include <map>
+#include <utility>
+
+#include "base/containers/scoped_ptr_hash_map.h"
+#include "base/mac/dispatch_source_mach.h"
+#include "base/mac/scoped_mach_port.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/singleton.h"
+#include "base/synchronization/lock.h"
+#include "content/common/mac/io_surface_manager.h"
+#include "content/common/mac/io_surface_manager_messages.h"
+#include "content/common/mac/io_surface_manager_token.h"
+
+namespace content {
+
+// Implementation of IOSurfaceManager that provides a mechanism for child
+// processes to register and acquire IOSurfaces through a Mach service.
+class CONTENT_EXPORT BrowserIOSurfaceManager : public IOSurfaceManager {
+ public:
+  // Returns the global BrowserIOSurfaceManager.
+  static BrowserIOSurfaceManager* GetInstance();
+
+  // Look up the IOSurfaceManager service port that's been registered with
+  // the bootstrap server. |pid| is the process ID of the service.
+  static base::mac::ScopedMachSendRight LookupServicePort(pid_t pid);
+
+  // Overridden from IOSurfaceManager:
+  bool RegisterIOSurface(int io_surface_id,
+                         int client_id,
+                         IOSurfaceRef io_surface) override;
+  void UnregisterIOSurface(int io_surface_id, int client_id) override;
+  IOSurfaceRef AcquireIOSurface(int io_surface_id) override;
+
+  // Performs any necessary setup that cannot happen in the constructor.
+  void EnsureRunning();
+
+  // Get the unique unguessable token that the GPU process can use to
+  // register/unregister IOSurface for use by clients.
+  IOSurfaceManagerToken GetGpuProcessToken() const;
+
+  // Generate a unique unguessable token that the child process associated
+  // |child_process_id| can use to acquire IOSurface references.
+  IOSurfaceManagerToken GenerateChildProcessToken(int child_process_id);
+
+  // Invalidate a previously generated token.
+  void InvalidateChildProcessToken(const IOSurfaceManagerToken& token);
+
+ private:
+  friend class BrowserIOSurfaceManagerTest;
+  friend struct DefaultSingletonTraits<BrowserIOSurfaceManager>;
+
+  BrowserIOSurfaceManager();
+  ~BrowserIOSurfaceManager() override;
+
+  // Performs any initialization work.
+  bool Initialize();
+
+  // Message handler that is invoked on |dispatch_source_| when an
+  // incoming message needs to be received.
+  void HandleRequest();
+
+  // Message handlers that are invoked from HandleRequest.
+  bool HandleRegisterIOSurfaceRequest(
+      const IOSurfaceManagerHostMsg_RegisterIOSurface& request,
+      IOSurfaceManagerMsg_RegisterIOSurfaceReply* reply);
+  bool HandleUnregisterIOSurfaceRequest(
+      const IOSurfaceManagerHostMsg_UnregisterIOSurface& request);
+  bool HandleAcquireIOSurfaceRequest(
+      const IOSurfaceManagerHostMsg_AcquireIOSurface& request,
+      IOSurfaceManagerMsg_AcquireIOSurfaceReply* reply);
+
+  // Whether or not the class has been initialized.
+  bool initialized_;
+
+  // The Mach port on which the server listens.
+  base::mac::ScopedMachReceiveRight server_port_;
+
+  // The dispatch source and queue on which Mach messages will be received.
+  scoped_ptr<base::DispatchSourceMach> dispatch_source_;
+
+  // Stores the IOSurfaces for all GPU clients. The key contains the IOSurface
+  // id and the Child process unique id of the owner.
+  using IOSurfaceMapKey = std::pair<int, int>;
+  using IOSurfaceMap =
+      base::ScopedPtrHashMap<IOSurfaceMapKey,
+                             scoped_ptr<base::mac::ScopedMachSendRight>>;
+  IOSurfaceMap io_surfaces_;
+
+  // Stores the Child process unique id (RenderProcessHost ID) for every
+  // token.
+  using ChildProcessIdMap = std::map<IOSurfaceManagerToken, int>;
+  ChildProcessIdMap child_process_ids_;
+
+  // Stores the GPU process token.
+  const IOSurfaceManagerToken gpu_process_token_;
+
+  // Mutex that guards |initialized_|, |io_surfaces_| and |child_process_ids_|.
+  mutable base::Lock lock_;
+
+  DISALLOW_COPY_AND_ASSIGN(BrowserIOSurfaceManager);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_BROWSER_IO_SURFACE_MANAGER_MAC_H_