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/* The clone3 syscall wrapper.
Copyright (C) 2022-2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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, see
<https://www.gnu.org/licenses/>. */
/* clone3() is even more special than fork() as it mucks with stacks
and invokes a function in the right context after its all over. */
#include <sys/asm.h>
#include <sysdep.h>
#define _ERRNO_H 1
#include <bits/errno.h>
#include <tls.h>
#include "tcb-offsets.h"
/* int clone3(struct clone_args *cl_args, size_t size,
int (*func)(void *arg), void *arg); */
ENTRY (__clone3)
/* Sanity check arguments. */
beqz a0, L (invalid) /* No NULL cl_args pointer. */
beqz a2, L (invalid) /* No NULL function pointer. */
/* Do the system call. */
LI a7, __NR_clone3
syscall 0
blt a0, zero ,L (error)
beqz a0, L (thread_start3)
/* Successful return from the parent. */
ret
L (invalid):
LI a0, -EINVAL
/* Something bad happened -- no child created. */
L (error):
b __syscall_error
END (__clone3)
/* Load up the arguments to the function. Put this block of code in
its own function so that we can terminate the stack trace with our
debug info. */
ENTRY (__thread_start3)
L (thread_start3):
/* Terminate call stack by noting ra is undefined. Use a dummy
.cfi_label to force starting the FDE. */
.cfi_label .Ldummy
cfi_undefined (1)
/* Align stack to 16. */
BSTRINS sp, zero, 3, 0
/* Set up arguments for the function call. */
move a0, a3 /* Argument. */
jirl ra, a2, 0 /* Call function. */
/* Call exit with the function's return value. */
LI a7, __NR_exit
syscall 0
END (__thread_start3)
libc_hidden_def (__clone3)
weak_alias (__clone3, clone3)
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