xref: /openbsd-src/lib/csu/crtbeginS.c (revision d13be5d47e4149db2549a9828e244d59dbc43f15)
1 /*	$OpenBSD: crtbeginS.c,v 1.11 2010/05/01 11:32:43 kettenis Exp $	*/
2 /*	$NetBSD: crtbegin.c,v 1.1 1996/09/12 16:59:03 cgd Exp $	*/
3 
4 /*
5  * Copyright (c) 1993 Paul Kranenburg
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *      This product includes software developed by Paul Kranenburg.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * Run-time module for GNU C++ compiled shared libraries.
36  *
37  * The linker constructs the following arrays of pointers to global
38  * constructors and destructors. The first element contains the
39  * number of pointers in each.
40  * The tables are also null-terminated.
41 
42  */
43 #include <stdlib.h>
44 
45 #include "md_init.h"
46 #include "os-note-elf.h"
47 #include "extern.h"
48 
49 /*
50  * java class registration hooks
51  */
52 
53 #if (__GNUC__ > 2)
54 static void *__JCR_LIST__[]
55     __attribute__((section(".jcr"), aligned(sizeof(void*)))) = { };
56 
57 extern void _Jv_RegisterClasses (void *)
58     __attribute__((weak));
59 #endif
60 
61 /*
62  * Include support for the __cxa_atexit/__cxa_finalize C++ abi for
63  * gcc > 2.x. __dso_handle is NULL in the main program and a unique
64  * value for each C++ shared library. For more info on this API, see:
65  *
66  *     http://www.codesourcery.com/cxx-abi/abi.html#dso-dtor
67  */
68 
69 #if (__GNUC__ > 2)
70 void *__dso_handle = &__dso_handle;
71 __asm(".hidden  __dso_handle");
72 
73 extern void __cxa_finalize(void *) __attribute__((weak));
74 #endif
75 
76 static init_f __CTOR_LIST__[1]
77     __attribute__((section(".ctors"))) = { (void *)-1 };	/* XXX */
78 static init_f __DTOR_LIST__[1]
79     __attribute__((section(".dtors"))) = { (void *)-1 };	/* XXX */
80 
81 static void	__dtors(void) __used;
82 static void	__ctors(void) __used;
83 
84 void
85 __dtors(void)
86 {
87 	unsigned long i = (unsigned long) __DTOR_LIST__[0];
88 	init_f *p;
89 
90 	if (i == -1)  {
91 		for (i = 1; __DTOR_LIST__[i] != NULL; i++)
92 			;
93 		i--;
94 	}
95 	p = __DTOR_LIST__ + i;
96 	while (i--) {
97 		(**p--)();
98 	}
99 }
100 
101 static void
102 __ctors(void)
103 {
104 	init_f *p = __CTOR_LIST__ + 1;
105 
106 	while (*p) {
107 		(**p++)();
108 	}
109 }
110 void _init(void);
111 void _fini(void);
112 static void _do_init(void) __used;
113 static void _do_fini(void) __used;
114 
115 MD_SECTION_PROLOGUE(".init", _init);
116 
117 MD_SECTION_PROLOGUE(".fini", _fini);
118 
119 MD_SECT_CALL_FUNC(".init", _do_init);
120 MD_SECT_CALL_FUNC(".fini", _do_fini);
121 
122 void
123 _do_init(void)
124 {
125 	static int initialized = 0;
126 
127 	/*
128 	 * Call global constructors.
129 	 * Arrange to call global destructors at exit.
130 	 */
131 	if (!initialized) {
132 		initialized = 1;
133 
134 #if (__GNUC__ > 2)
135 		if (__JCR_LIST__[0] && _Jv_RegisterClasses)
136 			_Jv_RegisterClasses(__JCR_LIST__);
137 #endif
138 
139 		__ctors();
140 	}
141 }
142 
143 void
144 _do_fini(void)
145 {
146 	static int finalized = 0;
147 	if (!finalized) {
148 		finalized = 1;
149 
150 #if (__GNUC__ > 2)
151 		if (__cxa_finalize != NULL)
152 			__cxa_finalize(__dso_handle);
153 #endif
154 
155 		/*
156 		 * since the _init() function sets up the destructors to
157 		 * be called by atexit, do not call the destructors here.
158 		 */
159 		__dtors();
160 	}
161 }
162