/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8     -*-│
│ vi: set noet ft=asm ts=8 sw=8 fenc=utf-8                                 :vi │
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2022 Justine Alexandra Roberts Tunney                              │
│                                                                              │
│ Permission to use, copy, modify, and/or distribute this software for         │
│ any purpose with or without fee is hereby granted, provided that the         │
│ above copyright notice and this permission notice appear in all copies.      │
│                                                                              │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
│ PERFORMANCE OF THIS SOFTWARE.                                                │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/macros.h"

#define SYS___tfork 8

//	Creates thread on OpenBSD.
//
//	@param	rdi is params
//	@param	rsi is size of params
//	@param	rdx is start function
//	@param	rcx is start parameter
//	@return	thread id or negative errno
__tfork_thread:
	mov	%rdx,%r8
	mov	%rcx,%r9
	mov	$SYS___tfork,%eax
	syscall
	jc	2f
	test	%eax,%eax
	jz	1f
	ret
1:	xor	%ebp,%ebp
	mov	%r9,%rdi
	jmp	*%r8
	.unreachable
2:	neg	%eax
	ret
	.endfn	__tfork_thread,globl
