1 /* $OpenBSD: crtbeginS.c,v 1.16 2015/04/07 01:27:06 guenther 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 static void *__JCR_LIST__[] 54 __attribute__((section(".jcr"), aligned(sizeof(void*)))) = { }; 55 56 extern void _Jv_RegisterClasses (void *) 57 __attribute__((weak)); 58 59 60 /* 61 * Include support for the __cxa_atexit/__cxa_finalize C++ abi for 62 * gcc > 2.x. __dso_handle is NULL in the main program and a unique 63 * value for each C++ shared library. For more info on this API, see: 64 * 65 * http://www.codesourcery.com/cxx-abi/abi.html#dso-dtor 66 */ 67 68 void *__dso_handle = &__dso_handle; 69 __asm(".hidden __dso_handle"); 70 71 long __guard_local __dso_hidden __attribute__((section(".openbsd.randomdata"))); 72 73 extern int __cxa_atexit(void (*)(void *), void *, void *) __attribute__((weak)); 74 extern void __cxa_finalize(void *) __attribute__((weak)); 75 76 int 77 atexit(void (*fn)(void)) 78 { 79 return (__cxa_atexit((void (*)(void *))fn, NULL, &__dso_handle)); 80 } 81 asm(".hidden atexit"); 82 83 /* 84 * Ditto for pthread_atfork() 85 */ 86 int _thread_atfork(void (*)(void), void (*)(void), void (*)(void), void *) 87 __attribute__((weak)); 88 89 int 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 98 static init_f __CTOR_LIST__[1] 99 __attribute__((section(".ctors"))) = { (void *)-1 }; /* XXX */ 100 static init_f __DTOR_LIST__[1] 101 __attribute__((section(".dtors"))) = { (void *)-1 }; /* XXX */ 102 103 static void __dtors(void) __used; 104 static void __ctors(void) __used; 105 106 void 107 __ctors(void) 108 { 109 unsigned long i = (unsigned long) __CTOR_LIST__[0]; 110 init_f *p; 111 112 if (i == -1) { 113 for (i = 1; __CTOR_LIST__[i] != NULL; i++) 114 ; 115 i--; 116 } 117 p = __CTOR_LIST__ + i; 118 while (i--) { 119 (**p--)(); 120 } 121 } 122 123 static void 124 __dtors(void) 125 { 126 init_f *p = __DTOR_LIST__ + 1; 127 128 while (*p) { 129 (**p++)(); 130 } 131 } 132 void _init(void); 133 void _fini(void); 134 static void _do_init(void) __used; 135 static void _do_fini(void) __used; 136 137 MD_SECTION_PROLOGUE(".init", _init); 138 139 MD_SECTION_PROLOGUE(".fini", _fini); 140 141 MD_SECT_CALL_FUNC(".init", _do_init); 142 MD_SECT_CALL_FUNC(".fini", _do_fini); 143 144 void 145 _do_init(void) 146 { 147 static int initialized = 0; 148 149 /* 150 * Call global constructors. 151 * Arrange to call global destructors at exit. 152 */ 153 if (!initialized) { 154 initialized = 1; 155 156 if (__JCR_LIST__[0] && _Jv_RegisterClasses) 157 _Jv_RegisterClasses(__JCR_LIST__); 158 __ctors(); 159 } 160 } 161 162 void 163 _do_fini(void) 164 { 165 static int finalized = 0; 166 if (!finalized) { 167 finalized = 1; 168 169 if (__cxa_finalize != NULL) 170 __cxa_finalize(__dso_handle); 171 172 /* 173 * since the _init() function sets up the destructors to 174 * be called by atexit, do not call the destructors here. 175 */ 176 __dtors(); 177 } 178 } 179