mach.subproj/mach_msg.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Mach Operating System
  24  * Copyright (c) 1991,1990,1989 Carnegie Mellon University
  25  * All Rights Reserved.
  26  *
  27  * Permission to use, copy, modify and distribute this software and its
  28  * documentation is hereby granted, provided that both the copyright
  29  * notice and this permission notice appear in all copies of the
  30  * software, derivative works or modified versions, and any portions
  31  * thereof, and that both notices appear in supporting documentation.
  32  *
  33  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  34  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  35  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  36  *
  37  * Carnegie Mellon requests users of this software to return to
  38  *
  39  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  40  *  School of Computer Science
  41  *  Carnegie Mellon University
  42  *  Pittsburgh PA 15213-3890
  43  *
  44  * any improvements or extensions that they make and grant Carnegie Mellon
  45  * the rights to redistribute these changes.
  46  */
  47
  48 #include <mach/port.h>
  49 #include <mach/message.h>
  50
  51 #define LIBMACH_OPTIONS (MACH_SEND_INTERRUPT|MACH_RCV_INTERRUPT)
  52
  53 mach_msg_return_t
  54 mach_msg(msg, option, send_size, rcv_size, rcv_name, timeout, notify)
  55         mach_msg_header_t *msg;
  56         mach_msg_option_t option;
  57         mach_msg_size_t send_size;
  58         mach_msg_size_t rcv_size;
  59         mach_port_t rcv_name;
  60         mach_msg_timeout_t timeout;
  61         mach_port_t notify;
  62 {
  63         mach_msg_return_t mr;
  64
  65         /*
  66          * Consider the following cases:
  67          *      1) Errors in pseudo-receive (eg, MACH_SEND_INTERRUPTED
  68          *      plus special bits).
  69          *      2) Use of MACH_SEND_INTERRUPT/MACH_RCV_INTERRUPT options.
  70          *      3) RPC calls with interruptions in one/both halves.
  71          *
  72          * We refrain from passing the option bits that we implement
  73          * to the kernel.  This prevents their presence from inhibiting
  74          * the kernel's fast paths (when it checks the option value).
  75          */
  76
  77         mr = mach_msg_overwrite_trap(msg, option &~ LIBMACH_OPTIONS,
  78                            send_size, rcv_size, rcv_name,
  79                            timeout, notify, MACH_MSG_NULL, 0);
  80         if (mr == MACH_MSG_SUCCESS)
  81                 return MACH_MSG_SUCCESS;
  82
  83         if ((option & MACH_SEND_INTERRUPT) == 0)
  84                 while (mr == MACH_SEND_INTERRUPTED)
  85                         mr = mach_msg_overwrite_trap(msg,
  86                                 option &~ LIBMACH_OPTIONS,
  87                                 send_size, rcv_size, rcv_name,
  88                                 timeout, notify, MACH_MSG_NULL, 0);
  89
  90         if ((option & MACH_RCV_INTERRUPT) == 0)
  91                 while (mr == MACH_RCV_INTERRUPTED)
  92                         mr = mach_msg_overwrite_trap(msg,
  93                                 option &~ (LIBMACH_OPTIONS|MACH_SEND_MSG),
  94                                 0, rcv_size, rcv_name,
  95                                 timeout, notify, MACH_MSG_NULL, 0);
  96
  97         return mr;
  98 }
  99
 100 mach_msg_return_t
 101 mach_msg_overwrite(msg, option, send_size, rcv_limit, rcv_name, timeout,
 102                    notify, rcv_msg, rcv_msg_size)
 103         mach_msg_header_t *msg;
 104         mach_msg_option_t option;
 105         mach_msg_size_t send_size;
 106         mach_msg_size_t rcv_limit;
 107         mach_port_t rcv_name;
 108         mach_msg_timeout_t timeout;
 109         mach_port_t notify;
 110         mach_msg_header_t *rcv_msg;
 111         mach_msg_size_t rcv_msg_size;
 112 {
 113         mach_msg_return_t mr;
 114
 115         /*
 116          * Consider the following cases:
 117          *      1) Errors in pseudo-receive (eg, MACH_SEND_INTERRUPTED
 118          *      plus special bits).
 119          *      2) Use of MACH_SEND_INTERRUPT/MACH_RCV_INTERRUPT options.
 120          *      3) RPC calls with interruptions in one/both halves.
 121          *
 122          * We refrain from passing the option bits that we implement
 123          * to the kernel.  This prevents their presence from inhibiting
 124          * the kernel's fast paths (when it checks the option value).
 125          */
 126
 127         mr = mach_msg_overwrite_trap(msg, option &~ LIBMACH_OPTIONS,
 128                            send_size, rcv_limit, rcv_name,
 129                            timeout, notify, rcv_msg, rcv_msg_size);
 130         if (mr == MACH_MSG_SUCCESS)
 131                 return MACH_MSG_SUCCESS;
 132
 133         if ((option & MACH_SEND_INTERRUPT) == 0)
 134                 while (mr == MACH_SEND_INTERRUPTED)
 135                         mr = mach_msg_overwrite_trap(msg,
 136                                 option &~ LIBMACH_OPTIONS,
 137                                 send_size, rcv_limit, rcv_name,
 138                                 timeout, notify, rcv_msg, rcv_msg_size);
 139
 140         if ((option & MACH_RCV_INTERRUPT) == 0)
 141                 while (mr == MACH_RCV_INTERRUPTED)
 142                         mr = mach_msg_overwrite_trap(msg,
 143                                 option &~ (LIBMACH_OPTIONS|MACH_SEND_MSG),
 144                                 0, rcv_limit, rcv_name,
 145                                 timeout, notify, rcv_msg, rcv_msg_size);
 146
 147         return mr;
 148 }