X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/0c530ab8987f0ae6a1a3d9284f40182b88852816..2d21ac55c334faf3a56e5634905ed6987fc787d4:/libsyscall/mach/mach_init.c diff --git a/libsyscall/mach/mach_init.c b/libsyscall/mach/mach_init.c new file mode 100644 index 000000000..ce2eeed8c --- /dev/null +++ b/libsyscall/mach/mach_init.c @@ -0,0 +1,268 @@ +/* + * Copyright (c) 1999 Apple Computer, Inc. All rights reserved. + * + * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ + * + * This file contains Original Code and/or Modifications of Original Code + * as defined in and that are subject to the Apple Public Source License + * Version 2.0 (the 'License'). You may not use this file except in + * compliance with the License. The rights granted to you under the License + * may not be used to create, or enable the creation or redistribution of, + * unlawful or unlicensed copies of an Apple operating system, or to + * circumvent, violate, or enable the circumvention or violation of, any + * terms of an Apple operating system software license agreement. + * + * Please obtain a copy of the License at + * http://www.opensource.apple.com/apsl/ and read it before using this file. + * + * The Original Code and all software distributed under the License are + * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER + * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, + * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. + * Please see the License for the specific language governing rights and + * limitations under the License. + * + * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ + */ +/* + * Mach Operating System + * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University + * All Rights Reserved. + * + * Permission to use, copy, modify and distribute this software and its + * documentation is hereby granted, provided that both the copyright + * notice and this permission notice appear in all copies of the + * software, derivative works or modified versions, and any portions + * thereof, and that both notices appear in supporting documentation. + * + * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" + * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR + * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. + * + * Carnegie Mellon requests users of this software to return to + * + * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU + * School of Computer Science + * Carnegie Mellon University + * Pittsburgh PA 15213-3890 + * + * any improvements or extensions that they make and grant Carnegie Mellon + * the rights to redistribute these changes. + */ + +#include +#include +#include +#include +#include +#include +#include +#include "externs.h" + +mach_port_t mach_task_self_ = MACH_PORT_NULL; +mach_port_t mach_host_self_ = MACH_PORT_NULL; + +__private_extern__ kern_return_t _host_mach_msg_trap_return_; + +vm_size_t vm_page_size; +vm_size_t vm_page_mask; +int vm_page_shift; + +/* + * Forward internal declarations for automatic mach_init during + * fork() implementation. + */ +/* fork() calls through atfork_child_routine */ +void (*_atfork_child_routine)(void); + +static void mach_atfork_child_routine(void); +static boolean_t first = TRUE; +static void (*previous_atfork_child_routine)(void); +static boolean_t mach_init_inited = FALSE; +extern int mach_init(void); +extern void _pthread_set_self(void *); +extern void cthread_set_self(void *); +extern void __libc_init(void); /* Libc initialization routine */ + +kern_return_t +host_page_size(__unused host_t host, vm_size_t *out_page_size) +{ + *out_page_size = PAGE_SIZE; + return KERN_SUCCESS; +} + +static void mach_atfork_child_routine(void) +{ + /* + * If an (*_atfork_child_routine)() was registered when + * mach_init was first called, then call that routine + * prior to performing our re-initialization. This ensures + * that the post-fork handlers are called in exactly the + * same order as the crt0 (exec) handlers. Any library + * that makes use of the _atfork_child_routine must follow + * the same technique. + */ + if (previous_atfork_child_routine) { + (*previous_atfork_child_routine)(); + } + mach_init_inited = FALSE; + mach_init(); +} + +mach_port_t +mach_host_self(void) +{ + return(host_self_trap()); +} + +int mach_init_doit(int forkchild) +{ + host_t host; + + /* + * Get the important ports into the cached values, + * as required by "mach_init.h". + */ + + mach_task_self_ = task_self_trap(); + host = host_self_trap(); + + + if (!forkchild) { + /* + * Set up the post-fork child handler in the libc stub + * to invoke this routine if this process forks. Save the + * previous value in order that we can call that handler + * prior to performing our postfork work. + */ + + first = FALSE; + previous_atfork_child_routine = _atfork_child_routine; + _atfork_child_routine = mach_atfork_child_routine; + _pthread_set_self(0); + cthread_set_self(0); + } + + /* + * Initialize the single mig reply port + */ + + mig_init(0); + + /* + * Cache some other valuable system constants + */ + + (void)host_page_size(host, &vm_page_size); + vm_page_mask = vm_page_size - 1; + if (vm_page_size == 0) { + /* guard against unlikely craziness */ + vm_page_shift = 0; + } else { + /* + * Unfortunately there's no kernel interface to get the + * vm_page_shift, but it's easy enough to calculate. + */ + for (vm_page_shift = 0; + (vm_page_size & (1 << vm_page_shift)) == 0; + vm_page_shift++) + continue; + } + + mach_port_deallocate(mach_task_self_, host); + + mach_init_ports(); + +#if WE_REALLY_NEED_THIS_GDB_HACK + /* + * Check to see if GDB wants us to stop + */ + { + task_user_data_data_t user_data; + mach_msg_type_number_t user_data_count = TASK_USER_DATA_COUNT; + + user_data.user_data = 0; + (void)task_info(mach_task_self_, TASK_USER_DATA, + (task_info_t)&user_data, &user_data_count); +#define MACH_GDB_RUN_MAGIC_NUMBER 1 +#ifdef MACH_GDB_RUN_MAGIC_NUMBER + /* This magic number is set in mach-aware gdb + * for RUN command to allow us to suspend user's + * executable (linked with this libmach!) + * with the code below. + * This hack should disappear when gdb improves. + */ + if ((int)user_data.user_data == MACH_GDB_RUN_MAGIC_NUMBER) { + kern_return_t ret; + user_data.user_data = 0; + + ret = task_suspend (mach_task_self_); + if (ret != KERN_SUCCESS) { + while(1) (void)task_terminate(mach_task_self_); + } + } +#undef MACH_GDB_RUN_MAGIC_NUMBER +#endif /* MACH_GDB_RUN_MAGIC_NUMBER */ + } +#endif /* WE_REALLY_NEED_THIS_GDB_HACK */ + + /* + * Reserve page 0 so that the program doesn't get it as + * the result of a vm_allocate() or whatever. + */ + { + vm_offset_t zero_page_start; + + zero_page_start = 0; + (void)vm_map(mach_task_self_, &zero_page_start, vm_page_size, + 0, FALSE, MEMORY_OBJECT_NULL, 0, TRUE, + VM_PROT_NONE, VM_PROT_NONE, VM_INHERIT_COPY); + /* ignore result, we don't care if it failed */ + } + + return(0); +} + + + + +/* + * mach_init() is called explicitly in static executables (including dyld) + * It is called implicitly by libSystem_initializer() in dynamic executables + */ +int mach_init(void) +{ + int ret; + + if (mach_init_inited) + return(0); + mach_init_inited = TRUE; + ret = mach_init_doit(0); + + return ret; +} + + + + +/* called by _cthread_fork_child() */ +int fork_mach_init(void) +{ + /* called only from child */ + return(mach_init_doit(1)); +} + +#undef mach_task_self + +mach_port_t +mach_task_self(void) +{ + return(task_self_trap()); +} + +mach_port_t +mach_thread_self(void) +{ + return(thread_self_trap()); +}