cosmopolitan/libc/calls/raise.c
2023-05-13 02:41:41 -07:00

80 lines
3.5 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 2020 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/calls.h"
#include "libc/calls/sig.internal.h"
#include "libc/calls/syscall-sysv.internal.h"
#include "libc/dce.h"
#include "libc/intrin/strace.internal.h"
#include "libc/runtime/internal.h"
#include "libc/sysv/consts/sicode.h"
#include "libc/sysv/consts/sig.h"
#include "libc/thread/tls.h"
#include "libc/thread/xnu.internal.h"
static textwindows inline bool HasWorkingConsole(void) {
return !!(__ntconsolemode[0] | __ntconsolemode[1] | __ntconsolemode[2]);
}
static noubsan void RaiseSigFpe(void) {
volatile int x = 0;
x = 1 / x;
}
/**
* Sends signal to self.
*
* This is basically the same as:
*
* tkill(gettid(), sig);
*
* Note `SIG_DFL` still results in process death for most signals.
*
* This function is not entirely equivalent to kill() or tkill(). For
* example, we raise `SIGTRAP` and `SIGFPE` the natural way, since that
* helps us support Windows. So if the raised signal has a signal
* handler, then the reported `si_code` might not be `SI_TKILL`.
*
* On Windows, if a signal results in the termination of the process
* then we use the convention `_Exit(128 + sig)` to notify the parent of
* the signal number.
*
* @param sig can be SIGALRM, SIGINT, SIGTERM, SIGKILL, etc.
* @return 0 if signal was delivered and returned, or -1 w/ errno
* @asyncsignalsafe
*/
int raise(int sig) {
int rc, tid, event;
STRACE("raise(%G) → ...", sig);
if (sig == SIGTRAP) {
DebugBreak();
rc = 0;
#ifndef __aarch64__
} else if (sig == SIGFPE) {
// TODO(jart): Why doesn't AARCH64 raise SIGFPE?
RaiseSigFpe();
rc = 0;
#endif
} else if (!IsWindows() && !IsMetal()) {
rc = sys_tkill(gettid(), sig, 0);
} else {
rc = __sig_raise(sig, SI_TKILL);
}
STRACE("...raise(%G) → %d% m", sig, rc);
return rc;
}