init.c

   1 /*
   2  * Copyright (c) 2007, 2008, 2011 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 #include <TargetConditionals.h> // for TARGET_OS_EMBEDDED
  30
  31 #include <_libkernel_init.h>
  32 #include <dlfcn.h>
  33 #include <errno.h>
  34
  35 struct ProgramVars; /* forward reference */
  36
  37 // system library initialisers
  38 extern void bootstrap_init(void);               // from liblaunch.dylib
  39 extern void mach_init(void);                    // from libsystem_mach.dylib
  40 extern void pthread_init(void);                 // from libc.a
  41 extern void __libc_init(const struct ProgramVars *vars, void (*atfork_prepare)(void), void (*atfork_parent)(void), void (*atfork_child)(void), const char *apple[]);    // from libc.a
  42 extern void __keymgr_initializer(void);         // from libkeymgr.a
  43 extern void _dyld_initializer(void);            // from libdyld.a
  44 extern void libdispatch_init(void);             // from libdispatch.a
  45 extern void _libxpc_initializer(void);          // from libxpc
  46
  47 // signal malloc stack logging that initialisation has finished
  48 extern void __stack_logging_early_finished(void); // form libsystem_c.dylib
  49
  50 // system library atfork handlers
  51 extern void _cthread_fork_prepare(void);
  52 extern void _cthread_fork_parent(void);
  53 extern void _cthread_fork_child(void);
  54 extern void _cthread_fork_child_postinit(void);
  55
  56 extern void _mach_fork_child(void);
  57 extern void _cproc_fork_child(void);
  58 extern void _libc_fork_child(void);
  59 extern void _notify_fork_child(void);
  60 extern void _dyld_fork_child(void);
  61 extern void xpc_atfork_prepare(void);
  62 extern void xpc_atfork_parent(void);
  63 extern void xpc_atfork_child(void);
  64
  65 // advance decls for below;
  66 void libSystem_atfork_prepare(void);
  67 void libSystem_atfork_parent(void);
  68 void libSystem_atfork_child(void);
  69
  70 // from mig_support.c in libc
  71 mach_port_t _mig_get_reply_port(void);
  72 void _mig_set_reply_port(mach_port_t);
  73
  74 void cthread_set_errno_self(int);
  75
  76 /*
  77  * libsyscall_initializer() initializes all of libSystem.dylib <rdar://problem/4892197>
  78  */
  79 static __attribute__((constructor))
  80 void libSystem_initializer(int argc, const char* argv[], const char* envp[], const char* apple[], const struct ProgramVars* vars)
  81 {
  82         _libkernel_functions_t libkernel_funcs = {
  83                 .get_reply_port = _mig_get_reply_port,
  84                 .set_reply_port = _mig_set_reply_port,
  85                 .get_errno = __error,
  86                 .set_errno = cthread_set_errno_self,
  87                 .dlsym = dlsym,
  88         };
  89
  90         _libkernel_init(libkernel_funcs);
  91
  92         bootstrap_init();
  93         mach_init();
  94         pthread_init();
  95         __libc_init(vars, libSystem_atfork_prepare, libSystem_atfork_parent, libSystem_atfork_child, apple);
  96         __keymgr_initializer();
  97         _dyld_initializer();
  98         libdispatch_init();
  99         _libxpc_initializer();
 100
 101         __stack_logging_early_finished();
 102
 103         /* <rdar://problem/11588042>
 104          * C99 standard has the following in section 7.5(3):
 105          * "The value of errno is zero at program startup, but is never set
 106          * to zero by any library function."
 107          */
 108         errno = 0;
 109 }
 110
 111 /*
 112  * libSystem_atfork_{prepare,parent,child}() are called by libc when we fork, then we deal with running fork handlers
 113  * for everyone else.
 114  */
 115 void libSystem_atfork_prepare(void)
 116 {
 117         xpc_atfork_prepare();
 118         _cthread_fork_prepare();
 119 }
 120
 121 void libSystem_atfork_parent(void)
 122 {
 123         _cthread_fork_parent();
 124         xpc_atfork_parent();
 125 }
 126
 127 void libSystem_atfork_child(void)
 128 {
 129         _dyld_fork_child();
 130         _cthread_fork_child();
 131
 132         bootstrap_init();
 133         _mach_fork_child();
 134         _cproc_fork_child();
 135         _libc_fork_child();
 136         _notify_fork_child();
 137         xpc_atfork_child();
 138
 139         _cthread_fork_child_postinit();
 140 }
 141
 142 /*
 143  *  Old crt1.o glue used to call through mach_init_routine which was used to initialize libSystem.
 144  *  LibSystem now auto-initializes but mach_init_routine is left for binary compatibility.
 145  */
 146 static void mach_init_old(void) {}
 147 void (*mach_init_routine)(void) = &mach_init_old;
 148
 149 /*
 150  *      This __crashreporter_info__ symbol is for all non-dylib parts of libSystem.
 151  */
 152 const char *__crashreporter_info__;
 153 asm (".desc __crashreporter_info__, 0x10");