brk.S revision 15634 
193023Snsouch/*-
293023Snsouch * Copyright (c) 1990 The Regents of the University of California.
393023Snsouch * All rights reserved.
4116349Sjmg *
593023Snsouch * This code is derived from software contributed to Berkeley by
693023Snsouch * William Jolitz.
793023Snsouch *
893023Snsouch * 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 *	$Id: brk.S,v 1.2 1995/01/23 01:29:39 davidg Exp $
37 */
38
39#if defined(SYSLIBC_RCS) && !defined(lint)
40	.text
41	.asciz "$Id: brk.S,v 1.2 1995/01/23 01:29:39 davidg Exp $"
42#endif /* SYSLIBC_RCS and not lint */
43
44#include "SYS.h"
45
46	.globl	HIDENAME(curbrk)
47	.globl	HIDENAME(minbrk)
48ENTRY(_brk)
49	jmp	ok
50
51ENTRY(brk)
52#ifdef PIC
53	movl	4(%esp),%eax
54	PIC_PROLOGUE
55	movl	PIC_GOT(HIDENAME(curbrk)),%edx	# set up GOT addressing
56	movl	PIC_GOT(HIDENAME(minbrk)),%ecx	#
57	cmpl	%eax,(%ecx)
58	PIC_EPILOGUE
59	jl	ok
60	movl	(%ecx),%eax
61	movl	%eax,4(%esp)
62ok:
63	lea	SYS_break,%eax
64	KERNCALL
65	jb	err
66	movl	4(%esp),%eax
67	movl	%eax,(%edx)
68	movl	$0,%eax
69	ret
70err:
71	PIC_PROLOGUE
72	jmp	PIC_PLT(HIDENAME(cerror))
73
74#else
75
76	movl	4(%esp),%eax
77	cmpl	%eax,HIDENAME(minbrk)
78	jl	ok
79	movl	HIDENAME(minbrk),%eax
80	movl	%eax,4(%esp)
81ok:
82	lea	SYS_break,%eax
83	KERNCALL
84	jb	err
85	movl	4(%esp),%eax
86	movl	%eax,HIDENAME(curbrk)
87	movl	$0,%eax
88	ret
89err:
90	jmp	HIDENAME(cerror)
91#endif
92