1 /* $OpenBSD: crtbeginS.c,v 1.21 2021/12/17 12:03:16 jca 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 #include <stdlib.h>
43
44 #include "md_init.h"
45 #include "os-note-elf.h"
46 #include "extern.h"
47
48 /*
49 * java class registration hooks
50 */
51
52 MD_DATA_SECTION_FLAGS_SYMBOL(".jcr", "aw", void *, __JCR_LIST__);
53
54 extern void _Jv_RegisterClasses (void *)
55 __attribute__((weak));
56
57
58 /*
59 * Include support for the __cxa_atexit/__cxa_finalize C++ abi for
60 * gcc > 2.x. __dso_handle is NULL in the main program and a unique
61 * value for each C++ shared library. For more info on this API, see:
62 *
63 * http://www.codesourcery.com/cxx-abi/abi.html#dso-dtor
64 */
65
66 void *__dso_handle = &__dso_handle;
67 __asm(".hidden __dso_handle");
68
69 long __guard_local __dso_hidden __attribute__((section(".openbsd.randomdata")));
70
71 extern int __cxa_atexit(void (*)(void *), void *, void *) __attribute__((weak));
72 extern void __cxa_finalize(void *) __attribute__((weak));
73
74 int
atexit(void (* fn)(void))75 atexit(void (*fn)(void))
76 {
77 return (__cxa_atexit((void (*)(void *))fn, NULL, &__dso_handle));
78 }
79 asm(".hidden atexit");
80
81 /*
82 * Ditto for pthread_atfork()
83 */
84 int _thread_atfork(void (*)(void), void (*)(void), void (*)(void), void *)
85 __attribute__((weak));
86 int pthread_atfork(void (*)(void), void (*)(void), void (*)(void))
87 __attribute__((weak));
88
89 int
pthread_atfork(void (* prep)(void),void (* parent)(void),void (* child)(void))90 pthread_atfork(void (*prep)(void), void (*parent)(void), void (*child)(void))
91 {
92 return (_thread_atfork(prep, parent, child, &__dso_handle));
93 }
94 /* hppa doesn't permit directives in first column, so space after newline */
95 asm(".hidden pthread_atfork\n .weak pthread_atfork");
96
97 MD_DATA_SECTION_SYMBOL_VALUE(".ctors", init_f, __CTOR_LIST__, -1);
98 MD_DATA_SECTION_SYMBOL_VALUE(".dtors", init_f, __DTOR_LIST__, -1);
99
100
101 static void
__ctors(void)102 __ctors(void)
103 {
104 unsigned long i = (unsigned long) __CTOR_LIST__[0];
105 const init_f *p;
106
107 if (i == -1) {
108 for (i = 1; __CTOR_LIST__[i] != NULL; i++)
109 ;
110 i--;
111 }
112 p = __CTOR_LIST__ + i;
113 while (i--)
114 (**p--)();
115 }
116
117 static void
__dtors(void)118 __dtors(void)
119 {
120 const init_f *p = __DTOR_LIST__ + 1;
121
122 while (*p)
123 (**p++)();
124 }
125
126 void _init(void);
127 void _fini(void);
128 static void _do_init(void) __used;
129 static void _do_fini(void) __used;
130
131 MD_SECTION_PROLOGUE(".init", _init);
132
133 MD_SECTION_PROLOGUE(".fini", _fini);
134
135 MD_SECT_CALL_FUNC(".init", _do_init);
136 MD_SECT_CALL_FUNC(".fini", _do_fini);
137
138
139 static void
_do_init(void)140 _do_init(void)
141 {
142 static int initialized;
143
144 /*
145 * Call global constructors.
146 * Arrange to call global destructors at exit.
147 */
148 if (!initialized) {
149 initialized = 1;
150
151 if (__JCR_LIST__[0] && _Jv_RegisterClasses)
152 _Jv_RegisterClasses(__JCR_LIST__);
153 __ctors();
154 }
155 }
156
157 static void
_do_fini(void)158 _do_fini(void)
159 {
160 static int finalized;
161
162 if (!finalized) {
163 finalized = 1;
164
165 if (__cxa_finalize != NULL)
166 __cxa_finalize(__dso_handle);
167
168 /*
169 * since the _init() function sets up the destructors to
170 * be called by atexit, do not call the destructors here.
171 */
172 __dtors();
173 }
174 }
175