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+/* 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)