MachMessageServer: eliminate argument redundancy

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,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
 #ifndef CRASHPAD_UTIL_MACH_MACH_MESSAGE_H_
 #define CRASHPAD_UTIL_MACH_MACH_MESSAGE_H_
 
 #include <mach/mach.h>
 #include <stdint.h>
 
 namespace crashpad {
 
+//! \brief Special constants used as `mach_msg_timeout_t` values.
+enum : mach_msg_timeout_t {
+  //! \brief When passed to MachMessageDeadlineFromTimeout(), that function will
+  //!     return #kMachMessageDeadlineNonblocking.
+  kMachMessageTimeoutNonblocking = 0,
+
+  //! \brief When passed to MachMessageDeadlineFromTimeout(), that function will
+  //!     return #kMachMessageDeadlineWaitIndefinitely.
+  kMachMessageTimeoutWaitIndefinitely = 0xffffffff,
+};
+
 //! \brief The time before which a MachMessageWithDeadline() call should
 //!     complete.
 //!
 //! A value of this type may be one of the special constants
-//! #kMachMessageNonblocking or #kMachMessageWaitIndefinitely. Any other values
-//! should be produced by calling MachMessageDeadlineFromTimeout().
+//! #kMachMessageDeadlineNonblocking or #kMachMessageDeadlineWaitIndefinitely.
+//! Any other values should be produced by calling
+//! MachMessageDeadlineFromTimeout().
 //!
 //! Internally, these are currently specified on the same time base as
 //! ClockMonotonicNanoseconds(), although this is an implementation detail.
 using MachMessageDeadline = uint64_t;
 
 //! \brief Special constants used as \ref MachMessageDeadline values.
 enum : MachMessageDeadline {
   //! \brief MachMessageWithDeadline() should not block at all in its operation.
-  kMachMessageNonblocking = 0,
+  kMachMessageDeadlineNonblocking = 0,
 
   //! \brief MachMessageWithDeadline() should wait indefinitely for the
   //!     requested operation to complete.
-  kMachMessageWaitIndefinitely = 0xffffffffffffffff,
+  kMachMessageDeadlineWaitIndefinitely = 0xffffffffffffffff,
 };
 
 //! \brief Computes the deadline for a specified timeout value.
 //!
 //! While deadlines exist on an absolute time scale, timeouts are relative. This
 //! function calculates the deadline as \a timeout_ms milliseconds after it
 //! executes.
 //!
-//! If \a timeout_ms is `0`, this function will return #kMachMessageNonblocking.
+//! If \a timeout_ms is #kMachMessageDeadlineNonblocking, this function will
+//! return #kMachMessageDeadlineNonblocking. If \a timeout_ms is
+//! #kMachMessageTimeoutWaitIndefinitely, this function will return
+//! #kMachMessageDeadlineWaitIndefinitely.
 MachMessageDeadline MachMessageDeadlineFromTimeout(
     mach_msg_timeout_t timeout_ms);
 
 //! \brief Runs `mach_msg()` with a deadline, as opposed to a timeout.
 //!
 //! This function is similar to `mach_msg()`, with the following differences:
 //!  - The `timeout` parameter has been replaced by \a deadline. The deadline
 //!    applies uniformly to a call that is requested to both send and receive
 //!    a message.
 //!  - The `MACH_SEND_TIMEOUT` and `MACH_RCV_TIMEOUT` bits in \a options are
@@ skipping 10 matching lines @@
 //! user-specified \a deadline.
 //!
 //! Except as noted, the parameters and return value are identical to those of
 //! `mach_msg()`.
 //!
 //! \param[in] deadline The time by which this call should complete. If the
 //!     deadline is exceeded, this call will return `MACH_SEND_TIMED_OUT` or
 //!     `MACH_RCV_TIMED_OUT`.
 //! \param[in] run_even_if_expired If `true`, a deadline that is expired when
 //!     this function is called will be treated as though a deadline of
-//!     #kMachMessageNonblocking had been specified. When `false`, an expired
-//!     deadline will result in a `MACH_SEND_TIMED_OUT` or `MACH_RCV_TIMED_OUT`
-//!     return value, even if the deadline is already expired when the function
-//!     is called.
+//!     #kMachMessageDeadlineNonblocking had been specified. When `false`, an
+//!     expired deadline will result in a `MACH_SEND_TIMED_OUT` or
+//!     `MACH_RCV_TIMED_OUT` return value, even if the deadline is already
+//!     expired when the function is called.
 mach_msg_return_t MachMessageWithDeadline(mach_msg_header_t* message,
                                           mach_msg_option_t options,
                                           mach_msg_size_t receive_size,
                                           mach_port_name_t receive_port,
                                           MachMessageDeadline deadline,
                                           mach_port_name_t notify_port,
                                           bool run_even_if_expired);
 
 //! \brief Initializes a reply message for a MIG server routine based on its
 //!     corresponding request.
@@ skipping 34 matching lines @@
 //!
 //! \return A pointer to the trailer following the received Mach message’s body.
 //!     The contents of the trailer depend on the options provided to
 //!     `mach_msg()` or a similar function when the message was received.
 const mach_msg_trailer_t* MachMessageTrailerFromHeader(
     const mach_msg_header_t* header);
 
 }  // namespace crashpad
 
 #endif  // CRASHPAD_UTIL_MACH_MACH_MESSAGE_H_