IPC: Add MojoHandleAttachment

ipc/ipc_message_attachment_set.h

 // Copyright (c) 2011 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 IPC_IPC_MESSAGE_ATTACHMENT_SET_H_
 #define IPC_IPC_MESSAGE_ATTACHMENT_SET_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 17 matching lines @@
 // -----------------------------------------------------------------------------
 class IPC_EXPORT MessageAttachmentSet
     : public base::RefCountedThreadSafe<MessageAttachmentSet> {
  public:
   MessageAttachmentSet();
 
   // Return the number of attachments
   unsigned size() const;
   // Return the number of file descriptors
   unsigned num_descriptors() const;
+  // Return the number of mojo handles in the attachment set
+  unsigned num_mojo_handles() const;
+
   // Return true if no unconsumed descriptors remain
   bool empty() const { return 0 == size(); }
 
   bool AddAttachment(scoped_refptr<MessageAttachment> attachment);
 
   // Take the nth attachment from the beginning of the set, Code using this
   // /must/ access the attachments in order, and must do it at most once.
   //
   // This interface is designed for the deserialising code as it doesn't
   // support close flags.
   //   returns: an attachment, or nullptr on error
   scoped_refptr<MessageAttachment> GetAttachmentAt(unsigned index);
 
+  // This must be called after transmitting the descriptors returned by
+  // PeekDescriptors. It marks all the descriptors as consumed and closes those
+  // which are auto-close.
+  void CommitAll();
+
 #if defined(OS_POSIX)
   // This is the maximum number of descriptors per message. We need to know this
   // because the control message kernel interface has to be given a buffer which
   // is large enough to store all the descriptor numbers. Otherwise the kernel
   // tells us that it truncated the control data and the extra descriptors are
   // lost.
   //
   // In debugging mode, it's a fatal error to try and add more than this number
   // of descriptors to a MessageAttachmentSet.
   static const size_t kMaxDescriptorsPerMessage = 7;
 
   // ---------------------------------------------------------------------------
   // Interfaces for transmission...
 
   // Fill an array with file descriptors without 'consuming' them. CommitAll
   // must be called after these descriptors have been transmitted.
   //   buffer: (output) a buffer of, at least, size() integers.
   void PeekDescriptors(base::PlatformFile* buffer) const;
-  // This must be called after transmitting the descriptors returned by
-  // PeekDescriptors. It marks all the descriptors as consumed and closes those
-  // which are auto-close.
-  void CommitAll();
   // Returns true if any contained file descriptors appear to be handles to a
   // directory.
   bool ContainsDirectoryDescriptor() const;
   // Fetch all filedescriptors with the "auto close" property.
   // Used instead of CommitAll() when closing must be handled manually.
   void ReleaseFDsToClose(std::vector<base::PlatformFile>* fds);
 
   // ---------------------------------------------------------------------------
 
   // ---------------------------------------------------------------------------
@@ skipping 22 matching lines @@
   // all the descriptors have been read (with GetNthDescriptor). Secondly, we
   // can check that they are read in order.
   mutable unsigned consumed_descriptor_highwater_;
 
   DISALLOW_COPY_AND_ASSIGN(MessageAttachmentSet);
 };
 
 }  // namespace IPC
 
 #endif  // IPC_IPC_MESSAGE_ATTACHMENT_SET_H_