diff options
Diffstat (limited to 'lib/libc/arm/sys/fork.S')
-rw-r--r-- | lib/libc/arm/sys/fork.S | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/lib/libc/arm/sys/fork.S b/lib/libc/arm/sys/fork.S new file mode 100644 index 0000000..fb07c87 --- /dev/null +++ b/lib/libc/arm/sys/fork.S @@ -0,0 +1,49 @@ +/* $NetBSD: fork.S,v 1.5 2003/08/07 16:42:04 agc Exp $ */ + +/*- + * Copyright (c) 1990 The Regents of the University of California. + * All rights reserved. + * + * 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. 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. + * + * from: @(#)fork.s 5.1 (Berkeley) 4/23/90 + */ + +#include <machine/asm.h> +__FBSDID("$FreeBSD$"); +#include "SYS.h" + +/* + * pid = fork(); + * + * On return from the SWI: + * r1 == 0 in parent process, r1 == 1 in child process. + * r0 == pid of child in parent, r0 == pid of parent in child. + */ + +_SYSCALL(fork) + sub r1, r1, #1 /* r1 == 0xffffffff if parent, 0 if child */ + and r0, r0, r1 /* r0 == 0 if child, else unchanged */ + mov r15, r14 |