xref: /netbsd-src/lib/libc/arch/i386/sys/sbrk.S (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
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 *	from: @(#)sbrk.s	5.1 (Berkeley) 4/23/90
37 *	$Id: sbrk.S,v 1.7 1994/10/26 19:49:49 mycroft Exp $
38 */
39
40#if defined(SYSLIBC_SCCS) && !defined(lint)
41	.text
42	.asciz "$Id: sbrk.S,v 1.7 1994/10/26 19:49:49 mycroft Exp $"
43#endif /* SYSLIBC_SCCS and not lint */
44
45#include "SYS.h"
46
47	.globl	_end
48	.globl	curbrk
49
50	.data
51curbrk:	.long	_end
52	.text
53
54ENTRY(sbrk)
55#ifdef PIC
56	movl	4(%esp),%ecx
57	PIC_PROLOGUE
58	movl	PIC_GOT(curbrk),%edx
59	PIC_EPILOGUE
60	movl	(%edx),%eax
61	addl	%eax,4(%esp)
62	movl	$(SYS_break),%eax
63	int	$0x80
64	jc	err
65	PIC_PROLOGUE
66	movl	PIC_GOT(curbrk),%edx
67	PIC_EPILOGUE
68	movl	(%edx),%eax
69	addl	%ecx,(%edx)
70	ret
71err:
72	jmp	PIC_PLT(cerror)
73
74#else
75
76	movl	4(%esp),%ecx
77	movl	curbrk,%eax
78	addl	%eax,4(%esp)
79	movl	$(SYS_break),%eax
80	int	$0x80
81	jc	err
82	movl	curbrk,%eax
83	addl	%ecx,curbrk
84	ret
85err:
86	jmp	cerror
87#endif
88