SystemConfiguration.fproj/SCDNotifierWait.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25
  26 /*
  27  * Modification History
  28  *
  29  * June 1, 2001                 Allan Nathanson <ajn@apple.com>
  30  * - public API conversion
  31  *
  32  * March 31, 2000               Allan Nathanson <ajn@apple.com>
  33  * - initial revision
  34  */
  35
  36 #include <mach/mach.h>
  37 #include <mach/mach_error.h>
  38
  39 #include <SystemConfiguration/SystemConfiguration.h>
  40 #include <SystemConfiguration/SCPrivate.h>
  41 #include "SCDynamicStoreInternal.h"
  42 #include "config.h"             /* MiG generated file */
  43
  44 static mach_msg_id_t
  45 waitForMachMessage(mach_port_t port)
  46 {
  47         kern_return_t           status;
  48         mach_msg_empty_rcv_t    *buf;
  49
  50         mach_msg_size_t         size = sizeof(mach_msg_empty_t) + MAX_TRAILER_SIZE;
  51
  52         status = vm_allocate(mach_task_self(), (vm_address_t *)&buf, size, TRUE);
  53         if (status != KERN_SUCCESS) {
  54                 SCLog(_sc_verbose, LOG_DEBUG, CFSTR("vm_allocate(): %s"), mach_error_string(status));
  55                 return -1;
  56         }
  57
  58         status = mach_msg(&buf->header,                 /* msg */
  59                           MACH_RCV_MSG,                 /* options */
  60                           0,                            /* send_size */
  61                           size,                         /* rcv_size */
  62                           port,                         /* rcv_name */
  63                           MACH_MSG_TIMEOUT_NONE,        /* timeout */
  64                           MACH_PORT_NULL);              /* notify */
  65         if (status != KERN_SUCCESS) {
  66                 SCLog(_sc_verbose, LOG_DEBUG, CFSTR("mach_msg(): %s"), mach_error_string(status));
  67                 return -1;
  68         }
  69
  70         return buf->header.msgh_id;
  71 }
  72
  73
  74 Boolean
  75 SCDynamicStoreNotifyWait(SCDynamicStoreRef store)
  76 {
  77         SCDynamicStorePrivateRef        storePrivate = (SCDynamicStorePrivateRef)store;
  78         kern_return_t                   status;
  79         mach_port_t                     port;
  80         mach_port_t                     oldNotify;
  81         int                             sc_status;
  82         mach_msg_id_t                   msgid;
  83
  84         SCLog(_sc_verbose, LOG_DEBUG, CFSTR("SCDynamicStoreNotifyWait:"));
  85
  86         if (!store) {
  87                 /* sorry, you must provide a session */
  88                 _SCErrorSet(kSCStatusNoStoreSession);
  89                 return FALSE;
  90         }
  91
  92         if (storePrivate->server == MACH_PORT_NULL) {
  93                 /* sorry, you must have an open session to play */
  94                 _SCErrorSet(kSCStatusNoStoreServer);
  95                 return FALSE;
  96         }
  97
  98         if (storePrivate->notifyStatus != NotifierNotRegistered) {
  99                 /* sorry, you can only have one notification registered at once */
 100                 _SCErrorSet(kSCStatusNotifierActive);
 101                 return FALSE;
 102         }
 103
 104         /* Allocating port (for server response) */
 105         status = mach_port_allocate(mach_task_self(), MACH_PORT_RIGHT_RECEIVE, &port);
 106         if (status != KERN_SUCCESS) {
 107                 SCLog(_sc_verbose, LOG_DEBUG, CFSTR("mach_port_allocate(): %s"), mach_error_string(status));
 108                 _SCErrorSet(status);
 109                 return FALSE;
 110         }
 111         SCLog(_sc_verbose, LOG_DEBUG, CFSTR("  port = %d"), port);
 112
 113         status = mach_port_insert_right(mach_task_self(),
 114                                         port,
 115                                         port,
 116                                         MACH_MSG_TYPE_MAKE_SEND);
 117         if (status != KERN_SUCCESS) {
 118                 SCLog(_sc_verbose, LOG_DEBUG, CFSTR("mach_port_insert_right(): %s"), mach_error_string(status));
 119                 (void) mach_port_destroy(mach_task_self(), port);
 120                 _SCErrorSet(status);
 121                 return FALSE;
 122         }
 123
 124         /* Request a notification when/if the server dies */
 125         status = mach_port_request_notification(mach_task_self(),
 126                                                 port,
 127                                                 MACH_NOTIFY_NO_SENDERS,
 128                                                 1,
 129                                                 port,
 130                                                 MACH_MSG_TYPE_MAKE_SEND_ONCE,
 131                                                 &oldNotify);
 132         if (status != KERN_SUCCESS) {
 133                 SCLog(_sc_verbose, LOG_DEBUG, CFSTR("mach_port_request_notification(): %s"), mach_error_string(status));
 134                 (void) mach_port_destroy(mach_task_self(), port);
 135                 _SCErrorSet(status);
 136                 return FALSE;
 137         }
 138
 139         if (oldNotify != MACH_PORT_NULL) {
 140                 SCLog(_sc_verbose, LOG_ERR, CFSTR("SCDynamicStoreNotifyWait(): why is oldNotify != MACH_PORT_NULL?"));
 141         }
 142
 143         SCLog(_sc_verbose, LOG_DEBUG, CFSTR("Requesting notification via mach port %d"), port);
 144         status = notifyviaport(storePrivate->server,
 145                                port,
 146                                0,
 147                                (int *)&sc_status);
 148
 149         if (status != KERN_SUCCESS) {
 150                 if (status != MACH_SEND_INVALID_DEST)
 151                         SCLog(_sc_verbose, LOG_DEBUG, CFSTR("notifyviaport(): %s"), mach_error_string(status));
 152                 (void) mach_port_destroy(mach_task_self(), storePrivate->server);
 153                 storePrivate->server = MACH_PORT_NULL;
 154                 _SCErrorSet(status);
 155                 return FALSE;
 156         }
 157
 158         if (sc_status != kSCStatusOK) {
 159                 _SCErrorSet(sc_status);
 160                 return FALSE;
 161         }
 162
 163         /* set notifier active */
 164         storePrivate->notifyStatus = Using_NotifierWait;
 165
 166         SCLog(_sc_verbose, LOG_DEBUG, CFSTR("Waiting..."));
 167
 168         msgid = waitForMachMessage(port);
 169
 170         /* set notifier inactive */
 171         storePrivate->notifyStatus = NotifierNotRegistered;
 172
 173         if (msgid == MACH_NOTIFY_NO_SENDERS) {
 174                 /* the server closed the notifier port */
 175                 SCLog(_sc_verbose, LOG_DEBUG, CFSTR("  notifier port closed, destroying port %d"), port);
 176                 _SCErrorSet(kSCStatusNoStoreServer);
 177                 return FALSE;
 178         }
 179
 180         if (msgid == -1) {
 181                 /* one of the mach routines returned an error */
 182                 SCLog(_sc_verbose, LOG_DEBUG, CFSTR("  communication with server failed, destroying port %d"), port);
 183                 (void) mach_port_destroy(mach_task_self(), port);
 184                 _SCErrorSet(kSCStatusNoStoreServer);
 185                 return FALSE;
 186         }
 187
 188         SCLog(_sc_verbose, LOG_DEBUG, CFSTR("Something changed, cancelling notification request"));
 189         status = notifycancel(storePrivate->server,
 190                               (int *)&sc_status);
 191
 192         if (status != KERN_SUCCESS) {
 193                 if (status != MACH_SEND_INVALID_DEST)
 194                         SCLog(_sc_verbose, LOG_DEBUG, CFSTR("notifycancel(): %s"), mach_error_string(status));
 195                 (void) mach_port_destroy(mach_task_self(), storePrivate->server);
 196                 storePrivate->server = MACH_PORT_NULL;
 197                 _SCErrorSet(status);
 198                 return FALSE;
 199         }
 200
 201         (void) mach_port_destroy(mach_task_self(), port);
 202
 203         return TRUE;
 204 }