Mojo: Add the beginnings of a proper embedder API.

mojo/system/core_impl.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_SYSTEM_CORE_IMPL_H_
 #define MOJO_SYSTEM_CORE_IMPL_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/containers/hash_tables.h"
 #include "base/memory/ref_counted.h"
 #include "base/synchronization/lock.h"
 #include "mojo/public/system/core_private.h"
 #include "mojo/system/system_impl_export.h"
 
 namespace mojo {
+
+namespace embedder {
+void Init();  // So it can be friended.
+}
+
 namespace system {
 
 class CoreImpl;
 class Dispatcher;
 
 namespace test {
 class CoreTestBase;
 }
 
-// |CoreImpl| is a singleton object that implements the Mojo system calls. With
-// the (obvious) exception of |Init()|, which must be called first (and the call
-// completed) before making any other calls, all the public methods are
-// thread-safe.
+// |CoreImpl| is a singleton object that implements the Mojo system calls. All
+// public methods are thread-safe.
 class MOJO_SYSTEM_IMPL_EXPORT CoreImpl : public Core {
  public:
   static void Init();
 
   // |CorePrivate| implementation:
   virtual MojoTimeTicks GetTimeTicksNow() OVERRIDE;
   virtual MojoResult Close(MojoHandle handle) OVERRIDE;
   virtual MojoResult Wait(MojoHandle handle,
                           MojoWaitFlags flags,
                           MojoDeadline deadline) OVERRIDE;
@@ skipping 35 matching lines @@
                               uint32_t* num_bytes,
                               MojoReadDataFlags flags) OVERRIDE;
   virtual MojoResult BeginReadData(MojoHandle data_pipe_consumer_handle,
                                    const void** buffer,
                                    uint32_t* buffer_num_bytes,
                                    MojoReadDataFlags flags) OVERRIDE;
   virtual MojoResult EndReadData(MojoHandle data_pipe_consumer_handle,
                                  uint32_t num_bytes_read) OVERRIDE;
 
  private:
+  friend void ::mojo::embedder::Init();

[darin (slow to review), 2014/01/10 22:48:54]

it doesn't work to just say "embedder::Init()" here?

[viettrungluu, 2014/01/11 00:30:38]

Done.

   friend class test::CoreTestBase;
 
   // The |busy| member is used only to deal with functions (in particular
   // |WriteMessage()|) that want to hold on to a dispatcher and later remove it
   // from the handle table, without holding on to the handle table lock.
   //
   // For example, if |WriteMessage()| is called with a handle to be sent, (under
   // the handle table lock) it must first check that that handle is not busy (if
   // it is busy, then it fails with |MOJO_RESULT_BUSY|) and then marks it as
   // busy. To avoid deadlock, it should also try to acquire the locks for all
@@ skipping 50 matching lines @@
   base::Lock handle_table_lock_;  // Protects the immediately-following members.
   HandleTableMap handle_table_;
   MojoHandle next_handle_;  // Invariant: never |MOJO_HANDLE_INVALID|.
 
   // ---------------------------------------------------------------------------
 
   DISALLOW_COPY_AND_ASSIGN(CoreImpl);
 };
 
 }  // namespace system
+
 }  // namespace mojo
 
 #endif  // MOJO_SYSTEM_CORE_IMPL_H_