1/* $OpenBSD: sbrk.S,v 1.16 2023/12/10 16:45:51 deraadt Exp $ */ 2/*- 3 * Copyright (c) 1990 The Regents of the University of California. 4 * All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * William Jolitz. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34#include "SYS.h" 35 36 .globl _end 37 .globl __curbrk 38 .hidden __curbrk 39 40 .data 41__curbrk: .long _end 42 END(__curbrk) 43 .type __curbrk,@object 44 45ENTRY_NB(sbrk) 46#ifdef __PIC__ 47 movl 4(%esp),%ecx 48 PIC_PROLOGUE 49 movl PIC_GOT(__curbrk),%edx 50 PIC_EPILOGUE 51 movl (%edx),%eax 52 addl %eax,4(%esp) 53 movl $(SYS_break),%eax 5499: int $0x80 55 PINSYSCALL(SYS_break, 99b) 56 jc 2f 57 PIC_PROLOGUE 58 movl PIC_GOT(__curbrk),%edx 59 PIC_EPILOGUE 60 movl (%edx),%eax 61 addl %ecx,(%edx) 62 63#else 64 65 movl 4(%esp),%ecx 66 movl __curbrk,%eax 67 addl %eax,4(%esp) 68 movl $(SYS_break),%eax 6998: int $0x80 70 PINSYSCALL(SYS_break, 98b) 71 jc 2f 72 movl __curbrk,%eax 73 addl %ecx,__curbrk 74#endif 75 ret 762: 77 SET_ERRNO() 78 ret 79END(sbrk) 80 .weak sbrk 81