libsyscall/mach/mach_init.c

   1 /*
   2  * Copyright (c) 1999-2010 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * Mach Operating System
  30  * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
  31  * All Rights Reserved.
  32  *
  33  * Permission to use, copy, modify and distribute this software and its
  34  * documentation is hereby granted, provided that both the copyright
  35  * notice and this permission notice appear in all copies of the
  36  * software, derivative works or modified versions, and any portions
  37  * thereof, and that both notices appear in supporting documentation.
  38  *
  39  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  40  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  41  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  42  *
  43  * Carnegie Mellon requests users of this software to return to
  44  *
  45  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  46  *  School of Computer Science
  47  *  Carnegie Mellon University
  48  *  Pittsburgh PA 15213-3890
  49  *
  50  * any improvements or extensions that they make and grant Carnegie Mellon
  51  * the rights to redistribute these changes.
  52  */
  53
  54 #include <mach/mach.h>
  55 #include <mach/boolean.h>
  56 #include <mach/machine/ndr_def.h>
  57 #include <mach/mach_traps.h>
  58 #include <mach/mach_host.h>
  59 #include <mach/mach_init.h>
  60 #include <mach/vm_param.h>
  61 #include <stdbool.h>
  62 #include "externs.h"
  63 #include "mig_reply_port.h"
  64
  65 mach_port_t     mach_task_self_ = MACH_PORT_NULL;
  66 #ifdef __i386__
  67 mach_port_t     mach_host_self_ = MACH_PORT_NULL;
  68 #endif
  69
  70 vm_size_t vm_page_size  = PAGE_SIZE;
  71 vm_size_t vm_page_mask  = PAGE_MASK;
  72 int vm_page_shift               = PAGE_SHIFT;
  73
  74 int mach_init(void);
  75 int _mach_fork_child(void);
  76
  77 static int mach_init_doit(bool forkchild);
  78
  79 extern void _pthread_set_self(void *);
  80 extern void cthread_set_self(void *);
  81
  82 kern_return_t
  83 host_page_size(__unused host_t host, vm_size_t *out_page_size)
  84 {
  85         *out_page_size = PAGE_SIZE;
  86         return KERN_SUCCESS;
  87 }
  88
  89 /*
  90  * mach_init() must be called explicitly in static executables (including dyld).
  91  * called by libSystem_initializer() in dynamic executables
  92  */
  93 int
  94 mach_init(void)
  95 {
  96         static bool mach_init_inited = false;
  97
  98         if (mach_init_inited) {
  99                 return 0;
 100         }
 101         mach_init_inited = true;
 102
 103         return mach_init_doit(false);
 104 }
 105
 106 // called by libSystem_atfork_child()
 107 int
 108 _mach_fork_child(void)
 109 {
 110         return mach_init_doit(true);
 111 }
 112
 113 int
 114 mach_init_doit(bool forkchild)
 115 {
 116         /*
 117          *      Get the important ports into the cached values,
 118          *      as required by "mach_init.h".
 119          */
 120         mach_task_self_ = task_self_trap();
 121
 122         /*
 123          *      Initialize the single mig reply port
 124          */
 125
 126         _pthread_set_self(0);
 127         _mig_init(0);
 128
 129 #if WE_REALLY_NEED_THIS_GDB_HACK
 130         /*
 131          * Check to see if GDB wants us to stop
 132          */
 133         {
 134         task_user_data_data_t   user_data;
 135         mach_msg_type_number_t  user_data_count = TASK_USER_DATA_COUNT;
 136
 137         user_data.user_data = 0;
 138         (void)task_info(mach_task_self_, TASK_USER_DATA,
 139                 (task_info_t)&user_data, &user_data_count);
 140 #define MACH_GDB_RUN_MAGIC_NUMBER 1
 141 #ifdef  MACH_GDB_RUN_MAGIC_NUMBER
 142         /* This magic number is set in mach-aware gdb
 143          *  for RUN command to allow us to suspend user's
 144          *  executable (linked with this libmach!)
 145          *  with the code below.
 146          * This hack should disappear when gdb improves.
 147          */
 148         if ((int)user_data.user_data == MACH_GDB_RUN_MAGIC_NUMBER) {
 149             kern_return_t ret;
 150             user_data.user_data = 0;
 151
 152             ret = task_suspend(mach_task_self_);
 153             if (ret != KERN_SUCCESS) {
 154                         while (1) {
 155                                 (void)task_terminate(mach_task_self_);
 156                         }
 157             }
 158         }
 159 #undef MACH_GDB_RUN_MAGIC_NUMBER
 160 #endif /* MACH_GDB_RUN_MAGIC_NUMBER */
 161         }
 162 #endif /* WE_REALLY_NEED_THIS_GDB_HACK */
 163
 164         return 0;
 165 }