diff options
Diffstat (limited to 'lib/libc/amd64/sys/vfork.S')
-rw-r--r-- | lib/libc/amd64/sys/vfork.S | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/lib/libc/amd64/sys/vfork.S b/lib/libc/amd64/sys/vfork.S new file mode 100644 index 0000000..181dae5 --- /dev/null +++ b/lib/libc/amd64/sys/vfork.S @@ -0,0 +1,80 @@ +/*- + * 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: Ovfork.S,v 1.3 1994/02/21 05:19:08 rgrimes Exp $ + */ + +#if defined(SYSLIBC_SCCS) && !defined(lint) + .asciz "@(#)Ovfork.s 5.1 (Berkeley) 4/23/90" +#endif /* SYSLIBC_SCCS and not lint */ + +#include "SYS.h" + +/* + * pid = vfork(); + * + * %edx == 0 in parent process, %edx == 1 in child process. + * %eax == pid of child in parent, %eax == pid of parent in child. + * + */ + .set vfork,66 +.globl _vfork +.type _vfork,@function + +_vfork: + popl %ecx /* my rta into ecx */ + movl $vfork, %eax + LCALL(7,0) + jb verror +vforkok: + cmpl $0,%edx /* child process? */ + jne child /* yes */ + jmp parent +.globl _errno +verror: +#ifdef PIC + PIC_PROLOGUE + movl PIC_GOT(_errno), %edx + movl %eax,(%edx) + PIC_EPILOGUE +#else + movl %eax,_errno +#endif + movl $-1,%eax + jmp %ecx +child: + movl $0,%eax +parent: + jmp %ecx |