sbrk.S revision 87006
1/*- 2 * Copyright (c) 1990 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * William Jolitz. 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 the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37#if defined(SYSLIBC_RCS) && !defined(lint) 38 .text 39 .asciz "$FreeBSD: head/lib/libc/i386/sys/sbrk.S 87006 2001-11-27 20:51:26Z jhb $" 40#endif /* SYSLIBC_RCS and not lint */ 41 42#include "SYS.h" 43 44 .globl CNAME(end) 45 .globl HIDENAME(minbrk) 46 .globl HIDENAME(curbrk) 47 48 .data 49HIDENAME(minbrk): .long CNAME(end) 50HIDENAME(curbrk): .long CNAME(end) 51 .text 52 53ENTRY(sbrk) 54#ifdef PIC 55 movl 4(%esp),%ecx 56 PIC_PROLOGUE 57 movl PIC_GOT(HIDENAME(curbrk)),%edx 58 movl (%edx),%eax 59 PIC_EPILOGUE 60 testl %ecx,%ecx 61 jz back 62 addl %eax,4(%esp) 63 mov $SYS_break,%eax 64 KERNCALL 65 jb err 66 PIC_PROLOGUE 67 movl PIC_GOT(HIDENAME(curbrk)),%edx 68 movl (%edx),%eax 69 addl %ecx,(%edx) 70 PIC_EPILOGUE 71back: 72 ret 73err: 74 PIC_PROLOGUE 75 jmp PIC_PLT(HIDENAME(cerror)) 76 77#else /* !PIC */ 78 79 movl 4(%esp),%ecx 80 movl HIDENAME(curbrk),%eax 81 testl %ecx,%ecx 82 jz back 83 addl %eax,4(%esp) 84 mov $SYS_break,%eax 85 KERNCALL 86 jb err 87 movl HIDENAME(curbrk),%eax 88 addl %ecx,HIDENAME(curbrk) 89back: 90 ret 91err: 92 jmp HIDENAME(cerror) 93#endif /* PIC */ 94