1 /* $OpenBSD: crtbegin.c,v 1.17 2013/12/28 18:38:42 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 #include <stdlib.h> 43 44 #include "md_init.h" 45 #include "os-note-elf.h" 46 #include "extern.h" 47 48 struct dwarf2_eh_object { 49 void *space[8]; 50 }; 51 52 void __register_frame_info(const void *, struct dwarf2_eh_object *) 53 __attribute__((weak)); 54 55 void __register_frame_info(const void *begin, struct dwarf2_eh_object *ob) 56 { 57 } 58 59 static const char __EH_FRAME_BEGIN__[] 60 __attribute__((section(".eh_frame"), aligned(4))) = { }; 61 62 /* 63 * java class registration hooks 64 */ 65 66 #if (__GNUC__ > 2) 67 static void *__JCR_LIST__[] 68 __attribute__((section(".jcr"), aligned(sizeof(void*)))) = { }; 69 70 extern void _Jv_RegisterClasses (void *) 71 __attribute__((weak)); 72 #endif 73 74 /* 75 * Include support for the __cxa_atexit/__cxa_finalize C++ abi for 76 * gcc > 2.x. __dso_handle is NULL in the main program and a unique 77 * value for each C++ shared library. For more info on this API, see: 78 * 79 * http://www.codesourcery.com/cxx-abi/abi.html#dso-dtor 80 */ 81 82 #if (__GNUC__ > 2) 83 void *__dso_handle = NULL; 84 __asm(".hidden __dso_handle"); 85 86 long __guard_local __dso_hidden __attribute__((section(".openbsd.randomdata"))); 87 88 extern int __cxa_atexit(void (*)(void *), void *, void *) __attribute__((weak)); 89 90 int 91 atexit(void (*fn)(void)) 92 { 93 return (__cxa_atexit((void (*)(void *))fn, NULL, NULL)); 94 } 95 #endif 96 97 static const init_f __CTOR_LIST__[1] 98 __attribute__((section(".ctors"))) = { (void *)-1 }; /* XXX */ 99 static const init_f __DTOR_LIST__[1] 100 __attribute__((section(".dtors"))) = { (void *)-1 }; /* XXX */ 101 102 static void __dtors(void) __used; 103 static void __ctors(void) __used; 104 105 static void 106 __ctors() 107 { 108 unsigned long i = (unsigned long) __CTOR_LIST__[0]; 109 const init_f *p; 110 111 if (i == -1) { 112 for (i = 1; __CTOR_LIST__[i] != NULL; i++) 113 ; 114 i--; 115 } 116 p = __CTOR_LIST__ + i; 117 while (i--) 118 (**p--)(); 119 } 120 121 static void 122 __dtors() 123 { 124 const init_f *p = __DTOR_LIST__ + 1; 125 126 while (*p) 127 (**p++)(); 128 } 129 130 void __init(void); 131 void __fini(void); 132 static void __do_init(void) __used; 133 static void __do_fini(void) __used; 134 135 MD_SECTION_PROLOGUE(".init", __init); 136 137 MD_SECTION_PROLOGUE(".fini", __fini); 138 139 MD_SECT_CALL_FUNC(".init", __do_init); 140 MD_SECT_CALL_FUNC(".fini", __do_fini); 141 142 143 void 144 __do_init() 145 { 146 static int initialized = 0; 147 static struct dwarf2_eh_object object; 148 149 /* 150 * Call global constructors. 151 * Arrange to call global destructors at exit. 152 */ 153 if (!initialized) { 154 initialized = 1; 155 156 __register_frame_info(__EH_FRAME_BEGIN__, &object); 157 158 #if (__GNUC__ > 2) 159 if (__JCR_LIST__[0] && _Jv_RegisterClasses) 160 _Jv_RegisterClasses(__JCR_LIST__); 161 #endif 162 163 (__ctors)(); 164 165 atexit(__fini); 166 } 167 } 168 169 void 170 __do_fini() 171 { 172 static int finalized = 0; 173 174 if (!finalized) { 175 finalized = 1; 176 /* 177 * Call global destructors. 178 */ 179 (__dtors)(); 180 } 181 } 182 183