| // Copyright 2016 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 MOJO_EDK_SYSTEM_BROKER_H_ |
| #define MOJO_EDK_SYSTEM_BROKER_H_ |
| |
| #include "base/macros.h" |
| #include "base/memory/ref_counted.h" |
| #include "base/memory/writable_shared_memory_region.h" |
| #include "base/synchronization/lock.h" |
| #include "mojo/edk/embedder/scoped_platform_handle.h" |
| |
| namespace mojo { |
| namespace edk { |
| |
| // The Broker is a channel to the broker process, which allows synchronous IPCs |
| // to fulfill shared memory allocation requests on some platforms. |
| class Broker { |
| public: |
| // Note: This is blocking, and will wait for the first message over |
| // |platform_handle|. |
| explicit Broker(ScopedInternalPlatformHandle platform_handle); |
| ~Broker(); |
| |
| // Returns the platform handle that should be used to establish a NodeChannel |
| // to the process which is inviting us to join its network. This is the first |
| // handle read off the Broker channel upon construction. |
| ScopedInternalPlatformHandle GetInviterInternalPlatformHandle(); |
| |
| // Request a shared buffer from the broker process. Blocks the current thread. |
| base::WritableSharedMemoryRegion GetWritableSharedMemoryRegion( |
| size_t num_bytes); |
| |
| private: |
| // Handle to the broker process, used for synchronous IPCs. |
| ScopedInternalPlatformHandle sync_channel_; |
| |
| // Handle to the inviter process which is recieved in the first first message |
| // over |sync_channel_|. |
| ScopedInternalPlatformHandle inviter_channel_; |
| |
| // Lock to only allow one sync message at a time. This avoids having to deal |
| // with message ordering since we can only have one request at a time |
| // in-flight. |
| base::Lock lock_; |
| |
| DISALLOW_COPY_AND_ASSIGN(Broker); |
| }; |
| |
| } // namespace edk |
| } // namespace mojo |
| |
| #endif // MOJO_EDK_SYSTEM_BROKER_H_ |