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/* Copyright (C) 1999-2016 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
<http://www.gnu.org/licenses/>. */
/* 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>
#include <tcb-offsets.h>
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
pid_t *ptid, void *tls, pid_t *ctid); */
.text
ENTRY(__clone)
/* sanity check arguments. */
tst r4, r4
bt/s 0f
tst r5, r5
bf 1f
0:
bra .Lsyscall_error
mov #-EINVAL,r0
1:
/* insert the args onto the new stack */
mov.l r7, @-r5
/* save the function pointer as the 0th element */
mov.l r4, @-r5
/* do the system call */
mov r6, r4
mov.l @r15, r6
mov.l @(8,r15), r7
mov.l @(4,r15), r0
mov #+SYS_ify(clone), r3
trapa #0x15
mov r0, r1
mov #-12, r2
shad r2, r1
not r1, r1 // r1=0 means r0 = -1 to -4095
tst r1, r1 // i.e. error in linux
bf .Lclone_end
.Lsyscall_error:
SYSCALL_ERROR_HANDLER
.Lclone_end:
tst r0, r0
bt 2f
.Lpseudo_end:
rts
nop
2:
/* terminate the stack frame */
mov #0, r14
mov r4, r0
shlr16 r0
tst #1, r0 // CLONE_THREAD = (1 << 16)
bf/s 4f
mov r4, r0
/* new pid */
shlr8 r0
tst #1, r0 // CLONE_VM = (1 << 8)
bf/s 3f
mov #-1, r0
mov #+SYS_ify(getpid), r3
trapa #0x15
3:
stc gbr, r1
mov.w .Lpidoff, r2
add r1, r2
mov.l r0, @r2
mov.w .Ltidoff, r2
add r1, r2
mov.l r0, @r2
4:
/* thread starts */
mov.l @r15, r1
jsr @r1
mov.l @(4,r15), r4
/* we are done, passing the return value through r0 */
mov.l .L3, r1
#ifdef SHARED
mov.l r12, @-r15
sts.l pr, @-r15
mov r0, r4
mova .LG, r0
mov.l .LG, r12
add r0, r12
mova .L3, r0
add r0, r1
jsr @r1
nop
lds.l @r15+, pr
rts
mov.l @r15+, r12
#else
jmp @r1
mov r0, r4
#endif
.align 2
.LG:
.long _GLOBAL_OFFSET_TABLE_
.L3:
.long PLTJMP(C_SYMBOL_NAME(_exit))
.Lpidoff:
.word PID - TLS_PRE_TCB_SIZE
.Ltidoff:
.word TID - TLS_PRE_TCB_SIZE
PSEUDO_END (__clone)
libc_hidden_def (__clone)
weak_alias (__clone, clone)
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