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 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 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 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 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 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 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