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    /*	$OpenBSD: rthread_fork.c,v 1.23 2017/10/29 08:45:53 mpi Exp $ */  | 
    
    
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    /*  | 
    
    
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     * Copyright (c) 2008 Kurt Miller <kurt@openbsd.org>  | 
    
    
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     * Copyright (c) 2008 Philip Guenther <guenther@openbsd.org>  | 
    
    
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     * Copyright (c) 2003 Daniel Eischen <deischen@freebsd.org>  | 
    
    
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     * All rights reserved.  | 
    
    
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     *  | 
    
    
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     * Redistribution and use in source and binary forms, with or without  | 
    
    
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     * modification, are permitted provided that the following conditions  | 
    
    
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     * are met:  | 
    
    
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     * 1. Redistributions of source code must retain the above copyright  | 
    
    
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     *    notice, this list of conditions and the following disclaimer.  | 
    
    
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     * 2. Neither the name of the author nor the names of any co-contributors  | 
    
    
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     *    may be used to endorse or promote products derived from this software  | 
    
    
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     *    without specific prior written permission.  | 
    
    
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     *  | 
    
    
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     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND  | 
    
    
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     * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE  | 
    
    
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     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE  | 
    
    
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     * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE  | 
    
    
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     * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL  | 
    
    
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     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS  | 
    
    
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     * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)  | 
    
    
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     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT  | 
    
    
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     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY  | 
    
    
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     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF  | 
    
    
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     * SUCH DAMAGE.  | 
    
    
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     *  | 
    
    
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     * $FreeBSD: /repoman/r/ncvs/src/lib/libc_r/uthread/uthread_atfork.c,v 1.1 2004/12/10 03:36:45 grog Exp $  | 
    
    
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     */  | 
    
    
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    #ifndef NO_PIC  | 
    
    
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    #include <sys/types.h>  | 
    
    
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    #include <elf.h>  | 
    
    
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    #pragma weak _DYNAMIC  | 
    
    
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    #endif  | 
    
    
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    #include <errno.h>  | 
    
    
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    #include <pthread.h>  | 
    
    
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    #include <stdio.h>  | 
    
    
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    #include <stdlib.h>  | 
    
    
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    #include <tib.h>  | 
    
    
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    #include <unistd.h>  | 
    
    
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    #include "rthread.h"  | 
    
    
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    #include "rthread_cb.h"  | 
    
    
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    /* make {fork,vfork,getthrid} call _thread_sys_{fork,vfork,getthrid} */ | 
    
    
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    REDIRECT_SYSCALL(fork);  | 
    
    
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    REDIRECT_SYSCALL(vfork);  | 
    
    
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    REDIRECT_SYSCALL(getthrid);  | 
    
    
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    static pid_t  | 
    
    
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    _dofork(pid_t (*sys_fork)(void))  | 
    
    
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    { | 
    
    
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    	pthread_t me;  | 
    
    
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    	pid_t newid;  | 
    
    
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    	extern int _post_threaded;  | 
    
    
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    ✗✓ | 
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    	if (!_threads_ready)  | 
    
    
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    		return sys_fork();  | 
    
    
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    	me = pthread_self();  | 
    
    
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    	/*  | 
    
    
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    	 * Protect important libc/ld.so critical areas across the fork call.  | 
    
    
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    	 * dlclose() will grab the atexit lock via __cxa_finalize() so lock  | 
    
    
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    	 * the dl_lock first. malloc()/free() can use arc4random(), so lock  | 
    
    
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    	 * malloc_lock before arc4_lock  | 
    
    
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    	 */  | 
    
    
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    #ifndef NO_PIC  | 
    
    
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    ✓✗ | 
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    	if (_DYNAMIC)  | 
    
    
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    		_rthread_dl_lock(0);  | 
    
    
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    #endif  | 
    
    
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    	newid = _thread_dofork(sys_fork);  | 
    
    
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    ✗✓ | 
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    	if (newid == 0) { | 
    
    
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    		struct tib *tib = me->tib;  | 
    
    
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    #ifndef NO_PIC  | 
    
    
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    		/* reinitialize the lock in the child */  | 
    
    
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    		if (_DYNAMIC)  | 
    
    
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    			_rthread_dl_lock(2);  | 
    
    
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    #endif  | 
    
    
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    		/* update this thread's structure */  | 
    
    
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    		tib->tib_tid = getthrid();  | 
    
    
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    		me->donesem.lock = _SPINLOCK_UNLOCKED;  | 
    
    
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    		me->flags_lock = _SPINLOCK_UNLOCKED;  | 
    
    
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    		/* reinit the thread list */  | 
    
    
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    		LIST_INIT(&_thread_list);  | 
    
    
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    		LIST_INSERT_HEAD(&_thread_list, me, threads);  | 
    
    
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    		_thread_lock = _SPINLOCK_UNLOCKED;  | 
    
    
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    		/* single threaded now */  | 
    
    
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    		__isthreaded = 0;  | 
    
    
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    		_post_threaded = 0; /* notyet... */  | 
    
    
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    	}  | 
    
    
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    #ifndef NO_PIC  | 
    
    
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    ✓✗ | 
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    	else if (_DYNAMIC)  | 
    
    
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    		_rthread_dl_lock(1);  | 
    
    
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    #endif  | 
    
    
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    	return newid;  | 
    
    
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    }  | 
    
    
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    pid_t  | 
    
    
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    _thread_fork(void)  | 
    
    
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    { | 
    
    
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    	return _dofork(&fork);  | 
    
    
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    }  | 
    
    
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    pid_t  | 
    
    
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    _thread_vfork(void)  | 
    
    
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    { | 
    
    
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    	return _dofork(&vfork);  | 
    
    
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    }  |