Mojo: add support for disallowing sync calls for a process.

mojo/edk/system/core.h

 // Copyright 2013 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_CORE_H_
 #define MOJO_EDK_SYSTEM_CORE_H_
 
 #include <memory>
 #include <vector>
 
@@ skipping 106 matching lines @@
   void RequestShutdown(const base::Closure& callback);
 
   // Watches on the given handle for the given signals, calling |callback| when
   // a signal is satisfied or when all signals become unsatisfiable. |callback|
   // must satisfy stringent requirements -- see |Awakable::Awake()| in
   // awakable.h. In particular, it must not call any Mojo system functions.
   MojoResult AsyncWait(MojoHandle handle,
                        MojoHandleSignals signals,
                        const base::Callback<void(MojoResult)>& callback);
 
+  MojoResult SetProperty(MojoPropertyType type, const void* value);
+
   // ---------------------------------------------------------------------------
 
   // The following methods are essentially implementations of the Mojo Core
   // functions of the Mojo API, with the C interface translated to C++ by
   // "mojo/edk/embedder/entrypoints.cc". The best way to understand the contract
   // of these methods is to look at the header files defining the corresponding
   // API functions, referenced below.
 
   // These methods correspond to the API functions defined in
   // "mojo/public/c/system/functions.h":
@@ skipping 14 matching lines @@
                    MojoWatchCallback callback,
                    uintptr_t context);
   MojoResult CancelWatch(MojoHandle handle, uintptr_t context);
   MojoResult AllocMessage(uint32_t num_bytes,
                           const MojoHandle* handles,
                           uint32_t num_handles,
                           MojoAllocMessageFlags flags,
                           MojoMessageHandle* message);
   MojoResult FreeMessage(MojoMessageHandle message);
   MojoResult GetMessageBuffer(MojoMessageHandle message, void** buffer);
+  MojoResult GetProperty(MojoPropertyType type, void* value);
 
   // These methods correspond to the API functions defined in
   // "mojo/public/c/system/wait_set.h":
   MojoResult CreateWaitSet(MojoHandle* wait_set_handle);
   MojoResult AddHandle(MojoHandle wait_set_handle,
                        MojoHandle handle,
                        MojoHandleSignals signals);
   MojoResult RemoveHandle(MojoHandle wait_set_handle,
                           MojoHandle handle);
   MojoResult GetReadyHandles(MojoHandle wait_set_handle,
@@ skipping 123 matching lines @@
   // This is lazily initialized on first access. Always use GetNodeController()
   // to access it.
   std::unique_ptr<NodeController> node_controller_;
 
   base::Lock handles_lock_;
   HandleTable handles_;
 
   base::Lock mapping_table_lock_;  // Protects |mapping_table_|.
   MappingTable mapping_table_;
 
+  base::Lock property_lock_;
+  // Properties that can be read using the MojoGetProperty() API.
+  bool property_sync_call_allowed_ = true;
+
   DISALLOW_COPY_AND_ASSIGN(Core);
 };
 
 }  // namespace edk
 }  // namespace mojo
 
 #endif  // MOJO_EDK_SYSTEM_CORE_H_