xref: /dragonfly/lib/libc/gen/_thread_init.c (revision abf903a5)
1 /*
2  * Copyright (c) 2001 Daniel Eischen <deischen@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Neither the name of the author nor the names of any co-contributors
11  *    may be used to endorse or promote products derived from this software
12  *    without specific prior written permission.
13  *
14  * THIS SOFTWARE IS PROVIDED BY DANIEL EISCHEN AND CONTRIBUTORS ``AS IS''
15  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  */
27 
28 #include <sys/cdefs.h>
29 #include <sys/types.h>
30 #include "libc_private.h"
31 
32 void	_thread_init_stub(void);
33 void	_nmalloc_thr_init(void);
34 void	_upmap_thr_init(void);
35 
36 int	_thread_autoinit_dummy_decl_stub = 0;
37 
38 /*
39  * This stub is overridden when libpthreads is linked in.  However,
40  * we can apply the constructor to the weak reference.  Instead the
41  * constructor is applied to the stub and we do a run-time check to
42  * see if the stub has been overridden by pthreads.
43  */
44 void _thread_init_stub(void) __attribute__ ((constructor));
45 __weak_reference(_thread_init_stub, _thread_init);
46 
47 void
48 _thread_init_stub(void)
49 {
50 	/*
51 	 * Only run libc related pthreads initialization from here
52 	 * if pthreads did not override the weak reference.  Otherwise
53 	 * pthreads will do it after setting up a real thread context.
54 	 */
55 	if (_thread_init == _thread_init_stub) {
56 		_libc_thr_init();
57 	}
58 }
59 
60 /*
61  * Pre-initialization prior to thread startup to avoid certain
62  * chicken-and-egg issues with low-level allocations.
63  */
64 void
65 _libc_thr_init(void)
66 {
67 	_nmalloc_thr_init();
68 	_upmap_thr_init();
69 }
70 
71 __weak_reference(_thread_autoinit_dummy_decl_stub, _thread_autoinit_dummy_decl);
72