cosmopolitan/libc/proc/fork-sysv.c
Jōshin e16a7d8f3b
flip et / noet in modelines
`et` means `expandtab`.

```sh
rg 'vi: .* :vi' -l -0 | \
  xargs -0 sed -i '' 's/vi: \(.*\) et\(.*\)  :vi/vi: \1 xoet\2:vi/'
rg 'vi: .*  :vi' -l -0 | \
  xargs -0 sed -i '' 's/vi: \(.*\)noet\(.*\):vi/vi: \1et\2  :vi/'
rg 'vi: .*  :vi' -l -0 | \
  xargs -0 sed -i '' 's/vi: \(.*\)xoet\(.*\):vi/vi: \1noet\2:vi/'
```
2023-12-07 22:17:11 -05:00

71 lines
3.1 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│ vi: set et ft=c ts=2 sts=2 sw=2 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/calls/syscall-sysv.internal.h"
#include "libc/dce.h"
#include "libc/runtime/syslib.internal.h"
#include "libc/sysv/consts/sig.h"
#include "libc/sysv/errfuns.h"
int sys_fork(void) {
#ifdef __x86_64__
axdx_t ad;
int ax, dx;
ad = __sys_fork();
ax = ad.ax;
dx = ad.dx;
if (IsXnu() && ax != -1) {
// eax always returned with childs pid
// edx is 0 for parent and 1 for child
ax &= dx - 1;
}
return ax;
#elif defined(__aarch64__)
if (IsLinux()) {
int flags = 17; // SIGCHLD
void *child_stack = 0;
void *parent_tidptr = 0;
void *newtls = 0;
void *child_tidptr = 0;
register long r0 asm("x0") = (long)flags;
register long r1 asm("x1") = (long)child_stack;
register long r2 asm("x2") = (long)parent_tidptr;
register long r3 asm("x3") = (long)newtls;
register long r4 asm("x4") = (long)child_tidptr;
register int res_x0 asm("x0");
asm volatile("mov\tx8,%1\n\t"
"svc\t0"
: "=r"(res_x0)
: "i"(220), "r"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4)
: "x8", "x16", "memory");
return _sysret(res_x0);
} else if (__syslib) {
return _sysret(__syslib->__fork());
} else {
return enosys();
}
#else
return enosys();
#endif
}