ChildPortHandshake: allow receive rights to be received

util/mach/mach_message.h

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 156 matching lines @@
 //!
 //! If the kernel is the message’s sender, a process ID of `0` will be returned.
 //!
 //! \param[in] trailer The trailer received with a Mach message.
 //!
 //! \return The process ID of the message’s sender, or `-1` on failure with a
 //!     message logged. It is considered a failure for \a trailer to not contain
 //!     audit information.
 pid_t AuditPIDFromMachMessageTrailer(const mach_msg_trailer_t* trailer);
 
+//! \brief Destroys or deallocates a Mach port received in a Mach message.
+//!
+//! This function disposes of port rights received in a Mach message. Receive
+//! rights will be destroyed with `mach_port_mod_refs()`. Send and send-once
+//! rights will be deallocated with `mach_port_deallocate()`.
+//!
+//! \param[in] port The port to destroy or deallocate.
+//! \param[in] port_right_type The right type held for \a port:
+//!     `MACH_MSG_TYPE_PORT_RECEIVE`, `MACH_MSG_TYPE_PORT_SEND`, or
+//!     `MACH_MSG_TYPE_PORT_SEND_ONCE`.
+//!
+//! \return `true` on success, or `false` on failure with a message logged.
+bool MachMessageDestroyReceivedPort(mach_port_t port,
+                                    mach_msg_type_name_t port_right_type);
+
 }  // namespace crashpad
 
 #endif  // CRASHPAD_UTIL_MACH_MACH_MESSAGE_H_