diff options
Diffstat (limited to 'lib/libc/i386/sys/brk.S')
-rw-r--r-- | lib/libc/i386/sys/brk.S | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/lib/libc/i386/sys/brk.S b/lib/libc/i386/sys/brk.S new file mode 100644 index 0000000..c8311bb --- /dev/null +++ b/lib/libc/i386/sys/brk.S @@ -0,0 +1,92 @@ +/*- + * Copyright (c) 1990 The Regents of the University of California. + * All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * William Jolitz. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $Id: brk.S,v 1.1 1994/08/05 01:18:39 wollman Exp $ + */ + +#if defined(SYSLIBC_RCS) && !defined(lint) + .text + .asciz "$Id$" +#endif /* SYSLIBC_RCS and not lint */ + +#include "SYS.h" + +#define SYS_brk 17 + + .globl curbrk + .globl minbrk +ENTRY(_brk) + jmp ok + +ENTRY(brk) +#ifdef PIC + movl 4(%esp),%eax + PIC_PROLOGUE + movl PIC_GOT(curbrk),%edx # set up GOT addressing + movl PIC_GOT(minbrk),%ecx # + cmpl %eax,(%ecx) + PIC_EPILOGUE + jl ok + movl (%ecx),%eax + movl %eax,4(%esp) +ok: + lea SYS_brk,%eax + LCALL(7,0) + jb err + movl 4(%esp),%eax + movl %eax,(%edx) + movl $0,%eax + ret +err: + jmp PIC_PLT(cerror) + +#else + + movl 4(%esp),%eax + cmpl %eax,minbrk + jl ok + movl minbrk,%eax + movl %eax,4(%esp) +ok: + lea SYS_brk,%eax + LCALL(7,0) + jb err + movl 4(%esp),%eax + movl %eax,curbrk + movl $0,%eax + ret +err: + jmp cerror +#endif |