mach/msg-destroy.c

   1 /*
   2  * Mach Operating System
   3  * Copyright (c) 1991,1990 Carnegie Mellon University
   4  * All Rights Reserved.
   5  *
   6  * Permission to use, copy, modify and distribute this software and its
   7  * documentation is hereby granted, provided that both the copyright
   8  * notice and this permission notice appear in all copies of the
   9  * software, derivative works or modified versions, and any portions
  10  * thereof, and that both notices appear in supporting documentation.
  11  *
  12  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  13  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  14  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  15  *
  16  * Carnegie Mellon requests users of this software to return to
  17  *
  18  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  19  *  School of Computer Science
  20  *  Carnegie Mellon University
  21  *  Pittsburgh PA 15213-3890
  22  *
  23  * any improvements or extensions that they make and grant Carnegie Mellon
  24  * the rights to redistribute these changes.
  25  */
  26 /*
  27  * (pre-GNU) HISTORY
  28  *
  29  * Revision 2.4  91/05/14  17:53:15  mrt
  30  *      Correcting copyright
  31  *
  32  * Revision 2.3  91/02/14  14:17:43  mrt
  33  *      Added new Mach copyright
  34  *      [91/02/13  12:44:15  mrt]
  35  *
  36  * Revision 2.2  90/08/06  17:24:22  rpd
  37  *      Created.
  38  *
  39  */
  40
  41 #include <libc-pointer-arith.h>
  42 #if 1
  43 #include <mach.h>
  44 #else
  45 /* This is what CMU did, but that fails to declare some used functions.  */
  46 #include <mach/port.h>
  47 #include <mach/message.h>
  48 #include <mach_init.h>
  49 #endif
  50
  51 static void mach_msg_destroy_port(mach_port_t, mach_msg_type_name_t);
  52 static void mach_msg_destroy_memory(vm_offset_t, vm_size_t);
  53
  54 /*
  55  *      Routine:        mach_msg_destroy
  56  *      Purpose:
  57  *              Deallocates all port rights and out-of-line memory
  58  *              found in a received message.
  59  */
  60
  61 void
  62 __mach_msg_destroy (mach_msg_header_t *msg)
  63 {
  64     mach_msg_bits_t mbits = msg->msgh_bits;
  65
  66     /*
  67      *  The msgh_local_port field doesn't hold a port right.
  68      *  The receive operation consumes the destination port right.
  69      */
  70
  71     mach_msg_destroy_port(msg->msgh_remote_port, MACH_MSGH_BITS_REMOTE(mbits));
  72
  73     if (mbits & MACH_MSGH_BITS_COMPLEX) {
  74         vm_offset_t saddr;
  75         vm_offset_t eaddr;
  76
  77         saddr = (vm_offset_t) (msg + 1);
  78         eaddr = (vm_offset_t) msg + msg->msgh_size;
  79
  80         while (saddr < eaddr) {
  81             mach_msg_type_long_t *type;
  82             mach_msg_type_name_t name;
  83             mach_msg_type_size_t size;
  84             mach_msg_type_number_t number;
  85             boolean_t is_inline;
  86             vm_size_t length;
  87             vm_offset_t addr;
  88
  89             type = (mach_msg_type_long_t *) saddr;
  90             is_inline = type->msgtl_header.msgt_inline;
  91             if (type->msgtl_header.msgt_longform) {
  92                     name = type->msgtl_name;
  93                     size = type->msgtl_size;
  94                     number = type->msgtl_number;
  95                     saddr += sizeof(mach_msg_type_long_t);
  96             } else {
  97                     name = type->msgtl_header.msgt_name;
  98                     size = type->msgtl_header.msgt_size;
  99                     number = type->msgtl_header.msgt_number;
 100                     saddr += sizeof(mach_msg_type_t);
 101             }
 102
 103             /* Calculate length of data in bytes... */
 104             length = ((number * size) + 7) >> 3;
 105             /* ... and round up using uintptr_t alignment */
 106             length = ALIGN_UP (length, __alignof__ (uintptr_t));
 107
 108             addr = is_inline ? saddr : * (vm_offset_t *) saddr;
 109
 110             if (MACH_MSG_TYPE_PORT_ANY(name)) {
 111                 mach_port_t *ports = (mach_port_t *) addr;
 112                 mach_msg_type_number_t i;
 113
 114                 for (i = 0; i < number; i++)
 115                     mach_msg_destroy_port(*ports++, name);
 116             }
 117
 118             if (is_inline) {
 119                 saddr += length;
 120             } else {
 121                 mach_msg_destroy_memory(addr, length);
 122                 saddr += sizeof(vm_offset_t);
 123             }
 124         }
 125     }
 126 }
 127
 128 weak_alias (__mach_msg_destroy, mach_msg_destroy)
 129 libc_hidden_def (__mach_msg_destroy)
 130
 131 static void
 132 mach_msg_destroy_port (mach_port_t port, mach_msg_type_name_t type)
 133 {
 134     if (MACH_PORT_VALID(port)) switch (type) {
 135       case MACH_MSG_TYPE_MOVE_SEND:
 136       case MACH_MSG_TYPE_MOVE_SEND_ONCE:
 137         /* destroy the send/send-once right */
 138         (void) __mach_port_deallocate(mach_task_self(), port);
 139         break;
 140
 141       case MACH_MSG_TYPE_MOVE_RECEIVE:
 142         /* destroy the receive right */
 143         (void) __mach_port_mod_refs(mach_task_self(), port,
 144                                     MACH_PORT_RIGHT_RECEIVE, -1);
 145         break;
 146
 147       case MACH_MSG_TYPE_MAKE_SEND:
 148         /* create a send right and then destroy it */
 149         (void) __mach_port_insert_right(mach_task_self(), port,
 150                                         port, MACH_MSG_TYPE_MAKE_SEND);
 151         (void) __mach_port_deallocate(mach_task_self(), port);
 152         break;
 153
 154       case MACH_MSG_TYPE_MAKE_SEND_ONCE:
 155         /* create a send-once right and then destroy it */
 156         (void) __mach_port_extract_right(mach_task_self(), port,
 157                                          MACH_MSG_TYPE_MAKE_SEND_ONCE,
 158                                          &port, &type);
 159         (void) __mach_port_deallocate(mach_task_self(), port);
 160         break;
 161     }
 162 }
 163
 164 static void
 165 mach_msg_destroy_memory (vm_offset_t addr, vm_size_t size)
 166 {
 167     if (size > 0)
 168         (void) __vm_deallocate(__mach_task_self(), addr, size);
 169 }