cosmopolitan/libc/intrin/exit.c
Justine Tunney 8f522cb702
Make improvements
This change progresses our AARCH64 support:

- The AARCH64 build and tests are now passing
- Add 128-bit floating-point support to printf()
- Fix clone() so it initializes cosmo's x28 TLS register
- Fix TLS memory layout issue with aarch64 _Alignas vars
- Revamp microbenchmarking tools so they work on aarch64
- Make some subtle improvements to aarch64 crash reporting
- Make kisdangerous() memory checks more accurate on aarch64
- Remove sys_open() since it's not available on Linux AARCH64

This change makes general improvements to Cosmo and Redbean:

- Introduce GetHostIsa() function in Redbean
- You can now feature check using pledge(0, 0)
- You can now feature check using unveil("",0)
- Refactor some more x86-specific asm comments
- Refactor and write docs for some libm functions
- Make the mmap() API behave more similar to Linux
- Fix WIFSIGNALED() which wrongly returned true for zero
- Rename some obscure cosmo keywords from noFOO to dontFOO
2023-06-03 08:12:22 -07:00

93 lines
4.1 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2021 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/dce.h"
#include "libc/intrin/promises.internal.h"
#include "libc/intrin/strace.internal.h"
#include "libc/nexgen32e/vendor.internal.h"
#include "libc/nt/runtime.h"
#include "libc/runtime/runtime.h"
#include "libc/sysv/consts/nr.h"
/**
* Terminates process, ignoring destructors and atexit() handlers.
*
* When running on bare metal, this function will reboot your computer
* by hosing the interrupt descriptors and triple faulting the system.
*
* @param exitcode is masked with 255 on unix (but not windows)
* @asyncsignalsafe
* @threadsafe
* @vforksafe
* @noreturn
*/
wontreturn void _Exit(int exitcode) {
int i;
STRACE("_Exit(%d)", exitcode);
if (!IsWindows() && !IsMetal()) {
// On Linux _Exit1 (exit) must be called in pledge("") mode. If we
// call _Exit (exit_group) when we haven't used pledge("stdio") then
// it'll terminate the process instead. On OpenBSD we must not call
// _Exit1 (__threxit) because only _Exit (exit) is whitelisted when
// operating in pledge("") mode.
if (!(IsLinux() && !PLEDGED(STDIO))) {
#ifdef __x86_64__
asm volatile("syscall"
: /* no outputs */
: "a"(__NR_exit_group), "D"(exitcode)
: "rcx", "r11", "memory");
#elif defined(__aarch64__)
register long x0 asm("x0") = exitcode;
asm volatile("mov\tx8,%0\n\t"
"mov\tx16,%1\n\t"
"svc\t0"
: /* no outputs */
: "i"(94), "i"(1), "r"(x0)
: "x8", "x16", "memory");
#else
#error "unsupported architecture"
#endif
}
// Inline _Exit1() just in case _Exit() isn't allowed by pledge()
#ifdef __x86_64__
asm volatile("syscall"
: /* no outputs */
: "a"(__NR_exit), "D"(exitcode)
: "rcx", "r11", "memory");
#else
register long r0 asm("x0") = exitcode;
asm volatile("mov\tx8,%0\n\t"
"mov\tx16,%1\n\t"
"svc\t0"
: /* no outputs */
: "i"(93), "i"(0x169), "r"(r0)
: "x8", "memory");
#endif
} else if (IsWindows()) {
ExitProcess(exitcode);
}
#ifdef __x86_64__
asm("push\t$0\n\t"
"push\t$0\n\t"
"cli\n\t"
"lidt\t(%rsp)");
for (;;) asm("ud2");
#else
unreachable;
#endif
}