Adding MOJO_HANDLE_SIGNAL_PEER_CLOSED to be notified when a peer is closed.

mojo/public/c/system/types.h

 // Copyright 2014 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.
 
 // This file contains types and constants/macros common to different Mojo system
 // APIs.
 //
 // Note: This header should be compilable as C.
 
 #ifndef MOJO_PUBLIC_C_SYSTEM_TYPES_H_
@@ skipping 131 matching lines @@
 #define MOJO_DEADLINE_INDEFINITE ((MojoDeadline) - 1)
 #endif
 
 // |MojoHandleSignals|: Used to specify signals that can be waited on for a
 // handle (and which can be triggered), e.g., the ability to read or write to
 // the handle.
 //   |MOJO_HANDLE_SIGNAL_NONE| - No flags. |MojoWait()|, etc. will return
 //       |MOJO_RESULT_FAILED_PRECONDITION| if you attempt to wait on this.
 //   |MOJO_HANDLE_SIGNAL_READABLE| - Can read (e.g., a message) from the handle.
 //   |MOJO_HANDLE_SIGNAL_WRITABLE| - Can write (e.g., a message) to the handle.
+//   |MOJO_HANDLE_SIGNAL_PEER_CLOSED| - The peer handle is closed.
 
 typedef uint32_t MojoHandleSignals;
 
 #ifdef __cplusplus
 const MojoHandleSignals MOJO_HANDLE_SIGNAL_NONE = 0;
 const MojoHandleSignals MOJO_HANDLE_SIGNAL_READABLE = 1 << 0;
 const MojoHandleSignals MOJO_HANDLE_SIGNAL_WRITABLE = 1 << 1;
+const MojoHandleSignals MOJO_HANDLE_SIGNAL_PEER_CLOSED = 1 << 2;
 #else
 #define MOJO_HANDLE_SIGNAL_NONE ((MojoHandleSignals)0)
 #define MOJO_HANDLE_SIGNAL_READABLE ((MojoHandleSignals)1 << 0)
 #define MOJO_HANDLE_SIGNAL_WRITABLE ((MojoHandleSignals)1 << 1)
+#define MOJO_HANDLE_SIGNAL_PEER_CLOSED ((MojoHandleSignals)1 << 2)
 #endif
 
 // TODO(vtl): Add out parameters with this to MojoWait/MojoWaitMany.
 // Note: This struct is not extensible (and only has 32-bit quantities), so it's
 // 32-bit-aligned.
 MOJO_STATIC_ASSERT(MOJO_ALIGNOF(int32_t) == 4, "int32_t has weird alignment");
 struct MOJO_ALIGNAS(4) MojoHandleSignalsState {
   MojoHandleSignals satisfied_signals;
   MojoHandleSignals satisfiable_signals;
 };
 MOJO_STATIC_ASSERT(sizeof(MojoHandleSignalsState) == 8,
                    "MojoHandleSignalsState has wrong size");
 
 #endif  // MOJO_PUBLIC_C_SYSTEM_TYPES_H_