SyncSocket Transit Descriptor - refactoring

base/sync_socket.h

Index: base/sync_socket.h
diff --git a/base/sync_socket.h b/base/sync_socket.h
index 71addd1e163a9ab16d201a961ba3ae5b3ed6972f..1c3ac4fc2f20622f3fbb620ab6ea57a4f38b3fcd 100644
--- a/base/sync_socket.h
+++ b/base/sync_socket.h
@@ -17,17 +17,24 @@
 
 #include "base/base_export.h"
 #include "base/compiler_specific.h"
+#include "base/process/process_handle.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/time/time.h"
 
+#if defined(OS_POSIX)
+#include "base/file_descriptor_posix.h"
+#endif
+
 namespace base {
 
 class BASE_EXPORT SyncSocket {
  public:
 #if defined(OS_WIN)
   typedef HANDLE Handle;
+  typedef Handle TransitDescriptor;

[no longer working on chromium, 2014/09/01 14:56:18]

The existing sync socket code is dealing with "handle", how about using
TransitHandle instead of TransitDescriptor?
But I will defer the decision to Tommi, please check with him.

[burnik, 2014/09/01 15:08:02]

Both work good for me. Agreed. Tommi should have a say.
On 2014/09/01 14:56:18, xians1 wrote:

 #else
   typedef int Handle;
+  typedef FileDescriptor TransitDescriptor;
 #endif
   static const Handle kInvalidHandle;
 
@@ -42,6 +49,15 @@ class BASE_EXPORT SyncSocket {
   // return, the sockets will both be valid and connected.
   static bool CreatePair(SyncSocket* socket_a, SyncSocket* socket_b);
 
+  // Returns |Handle| wrapped in a |TransitDescriptor|.
+  static Handle UnwrapHandle(const TransitDescriptor& descriptor);
+
+  // Prepares a |TransitDescriptor| which wraps |Handle| used for transit.
+  // This is used to prepare the underlying shared resource before passing back
+  // the foreign handle to the peer process.

[no longer working on chromium, 2014/09/01 14:56:18]

s/foreign handle/transit handle/g

[burnik, 2014/09/01 15:08:02]

If we change to |TransitHandle| then agreed.
On 2014/09/01 14:56:18, xians1 wrote:

[no longer working on chromium, 2014/09/02 10:25:04]

There is no "foreign" concept in the code or comments of sync_socket.h, and in
real use case, clients are passing the TransmitDescript to the peer process.
I think you you need to change foreign to transit regardless the naming of
TransitHandle.

[burnik, 2014/09/02 15:01:34]

Done.

+  bool PrepareTransitDescriptor(ProcessHandle peer_process_handle,
+                                TransitDescriptor * descriptor);

[henrika (OOO until Aug 14), 2014/09/01 14:30:43]

nit, TransitDescriptor*

[burnik, 2014/09/01 14:59:33]

Done.

+
   // Closes the SyncSocket.  Returns true on success, false on failure.
   virtual bool Close();