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/*
* ========================
* ===== ===============
* ====== ================
* ====== ================
* ====== ==== ==== ==
* ====== === == = =
* ====== === = == =
* = === === = == ====
* = === === = == = =
* == ===== ==== ==
* ========================
*
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 2020 Joe
* 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 organization 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 JOE ''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 JOE 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.
*
* bsdsetsid: src/c_bsdsetsid.S
* 2020-11-20 19:45
* Joe
*
* This is the entrypoint of the program.
*/
.data
status: .space 4, 0x0
.text
.globl main
c_hex_dec:
xor %r10, %r10
xor %r9, %r9
xor %r8, %r8
mov $0xa, %rbx
clc
.repeat:
xor %rdx, %rdx
idiv %rbx
or $0x0, %dl
mov $0x8, %rcx
.shift:
rcrb $0x1, %dl
rcr $0x1, %r10
rcr $0x1, %r9
rcr $0x1, %r8
dec %rcx
and %rcx, %rcx
jnz .shift
and %rax, %rax
jnz .repeat
jmp c_parent_next
main:
cmpb $0x1, %dil
jle e_noarg
xor %rax, %rax
movb $0x2, %al
push %rdi
push %rsi
push %rdx
syscall
test %rax, %rax
js e_fork
jz c_child
c_parent:
mov %rax, %rdi
lea status, %rsi
xor %rdx, %rdx
xor %rcx, %rcx
xor %rax, %rax
movb $0x7, %al /* SYS_wait4 */
syscall
movq (%rsi), %rax
and $0xff00, %rax
shr $0x8, %rax
push %rax
jmp c_hex_dec
c_parent_next:
pop %rdi
movb $0x7, %al
xor %rax, %rax
movb $0x1, %al /* SYS_exit */
syscall
c_child:
# xor %rax, %rax
# movb $0x93, %al /* SYS_setsid */
# syscall
# jc e_setsid
xor %rax, %rax
pop %rdx
pop %rsi
pop %rdi
mov $0x1, %rcx
mov (%rsi, %rcx, 8), %rdi
lea 0(%rsi, %rcx, 8), %rsi
movb $0x3b, %al /* SYS_execve */
syscall
jc e_execve
c_exit:
xor %rdi, %rdi
xor %rax, %rax
movb $0x1, %al /* SYS_exit */
syscall
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