diff options
Diffstat (limited to 'libc/sysdeps/linux')
| -rw-r--r-- | libc/sysdeps/linux/arm/clone.S | 62 | 
1 files changed, 62 insertions, 0 deletions
| diff --git a/libc/sysdeps/linux/arm/clone.S b/libc/sysdeps/linux/arm/clone.S new file mode 100644 index 000000000..c9a1ec23a --- /dev/null +++ b/libc/sysdeps/linux/arm/clone.S @@ -0,0 +1,62 @@ +/* Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc. +   This file is part of the GNU C Library. +   Contributed by Pat Beirne <patb@corelcomputer.com> + +   The GNU C Library is free software; you can redistribute it and/or +   modify it under the terms of the GNU Lesser General Public +   License as published by the Free Software Foundation; either +   version 2.1 of the License, or (at your option) any later version. + +   The GNU C Library is distributed in the hope that it will be useful, +   but WITHOUT ANY WARRANTY; without even the implied warranty of +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU +   Lesser General Public License for more details. + +   You should have received a copy of the GNU Lesser General Public +   License along with the GNU C Library; if not, write to the Free +   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA +   02111-1307 USA.  */ + +/* clone() is even more special than fork() as it mucks with stacks +   and invokes a function in the right context after its all over.  */ + +#include <sysdep.h> +#define _ERRNO_H	1 +#include <bits/errno.h> + +/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg); */ + +        .text +ENTRY(__clone) +	@ sanity check args +	cmp	r0, #0 +	cmpne	r1, #0 +	moveq	r0, #-EINVAL +	beq	PLTJMP(syscall_error) + +	@ insert the args onto the new stack +	sub	r1, r1, #8 +	str	r3, [r1, #4] +	@ save the function pointer as the 0th element +	str	r0, [r1] + +	@ do the system call +	@ get flags +	mov	r0, r2 +	@ new sp is already in r1 +	swi	SYS_ify(clone) +	movs	a1, a1 +	blt	PLTJMP(C_SYMBOL_NAME(__syscall_error)) +	RETINSTR(movne, pc, lr) + +	@ pick the function arg and call address off the stack and execute +	ldr	r0, [sp, #4] +	mov	lr, pc +	ldr 	pc, [sp] + +	@ and we are done, passing the return value through r0 +	b	PLTJMP(_exit) + +PSEUDO_END (__clone) + +weak_alias (__clone, clone) | 
