1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22/* 23 * Copyright (c) 1988 AT&T 24 * All Rights Reserved 25 * 26 * 27 * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 28 * Use is subject to license terms. 29 */ 30 31/* 32 * Bootstrap routine for run-time linker. 33 * We get control from exec which has loaded our text and 34 * data into the process' address space and created the process 35 * stack. 36 * 37 * On entry, the process stack looks like this: 38 * 39 * # # <- %esp 40 * #_______________________# high addresses 41 * # strings # 42 * #_______________________# 43 * # 0 word # 44 * #_______________________# 45 * # Auxiliary # 46 * # entries # 47 * # ... # 48 * # (size varies) # 49 * #_______________________# 50 * # 0 word # 51 * #_______________________# 52 * # Environment # 53 * # pointers # 54 * # ... # 55 * # (one word each) # 56 * #_______________________# 57 * # 0 word # 58 * #_______________________# 59 * # Argument # low addresses 60 * # pointers # 61 * # Argc words # 62 * #_______________________# 63 * # argc # 64 * #_______________________# <- %ebp 65 * 66 * 67 * We must calculate the address at which ld.so was loaded, 68 * find the addr of the dynamic section of ld.so, of argv[0], and of 69 * the process' environment pointers - and pass the thing to _setup 70 * to handle. We then call _rtld - on return we jump to the entry 71 * point for the a.out. 72 */ 73 74#if defined(lint) 75 76extern unsigned long _setup(); 77extern void atexit_fini(); 78void 79main() 80{ 81 (void) _setup(); 82 atexit_fini(); 83} 84 85#else 86 87#include <link.h> 88 89 .file "boot.s" 90 .text 91 .globl _rt_boot 92 .globl _setup 93 .globl _GLOBAL_OFFSET_TABLE_ 94 .type _rt_boot,@function 95 .align 4 96 97 / init is called from the _init symbol in the CRT, however .init_array 98 / are called "naturally" from call_init. Because of that, we need the 99 / stack aligned here so that initializers called via _array sections may 100 / safely use SIMD instructions. 101_rt_alias: 102 jmp .get_ip / in case we were invoked from libc.so 103_rt_boot: 104 movl %esp,%ebp / save for referencing args 105 subl $EB_MAX_SIZE32,%esp / make room for a max sized boot vector 106 andl $-16,%esp 107 subl $8,%esp 108 movl %esp,%esi / use esi as a pointer to &eb[0] 109 movl $EB_ARGV,0(%esi) / set up tag for argv 110 leal 4(%ebp),%eax / get address of argv 111 movl %eax,4(%esi) / put after tag 112 movl $EB_ENVP,8(%esi) / set up tag for envp 113 movl (%ebp),%eax / get # of args 114 addl $2,%eax / one for the zero & one for argc 115 leal (%ebp,%eax,4),%edi / now points past args & @ envp 116 movl %edi,12(%esi) / set envp 117.L0: addl $4,%edi / next 118 cmpl $0,-4(%edi) / search for 0 at end of env 119 jne .L0 120 movl $EB_AUXV,16(%esi) / set up tag for auxv 121 movl %edi,20(%esi) / point to auxv 122 movl $EB_NULL,24(%esi) / set up NULL tag 123.get_ip: 124 call .L1 / only way to get IP into a register 125.L1: 126 popl %ebx / pop the IP we just "pushed" 127 addl $_GLOBAL_OFFSET_TABLE_+[.-.L1],%ebx 128 pushl (%ebx) / address of dynamic structure 129 pushl %esi / push &eb[0] 130 131 call _setup@PLT / _setup(&eb[0], _DYNAMIC) 132 movl %ebp,%esp / release stack frame 133 134 movl atexit_fini@GOT(%ebx), %edx 135 jmp *%eax / transfer control to a.out 136 .size _rt_boot,.-_rt_boot 137 138#endif 139