cosmopolitan/libc/thread/itimer.c
Justine Tunney a15958edc6
Remove some legacy cruft
Function trace logs will report stack usage accurately. It won't include
the argv/environ block. Our clone() polyfill is now simpler and does not
use as much stack memory. Function call tracing on x86 is now faster too
2025-01-02 18:44:07 -08:00

123 lines
5.2 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 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/sysv/consts/itimer.h"
#include "libc/calls/sig.internal.h"
#include "libc/calls/state.internal.h"
#include "libc/calls/struct/itimerval.h"
#include "libc/calls/struct/itimerval.internal.h"
#include "libc/calls/struct/sigset.internal.h"
#include "libc/calls/struct/timeval.h"
#include "libc/cosmo.h"
#include "libc/intrin/maps.h"
#include "libc/intrin/strace.h"
#include "libc/nt/enum/processcreationflags.h"
#include "libc/nt/thread.h"
#include "libc/runtime/runtime.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/clock.h"
#include "libc/sysv/consts/map.h"
#include "libc/sysv/consts/prot.h"
#include "libc/sysv/consts/sicode.h"
#include "libc/sysv/consts/sig.h"
#include "libc/sysv/errfuns.h"
#include "libc/thread/itimer.h"
#include "libc/thread/posixthread.internal.h"
#include "libc/thread/thread2.h"
#include "libc/thread/tls.h"
#ifdef __x86_64__
#define STACK_SIZE 65536
textwindows dontinstrument static uint32_t __itimer_worker(void *arg) {
struct CosmoTib tls;
char *sp = __builtin_frame_address(0);
__bootstrap_tls(&tls, sp);
__maps_track(
(char *)(((uintptr_t)sp + __pagesize - 1) & -__pagesize) - STACK_SIZE,
STACK_SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_NOFORK);
for (;;) {
bool dosignal = false;
struct timeval now, waituntil;
__itimer_lock();
now = timeval_real();
if (timeval_iszero(__itimer.it.it_value)) {
waituntil = timeval_max;
} else {
if (timeval_cmp(now, __itimer.it.it_value) < 0) {
waituntil = __itimer.it.it_value;
} else {
if (timeval_iszero(__itimer.it.it_interval)) {
__itimer.it.it_value = timeval_zero;
waituntil = timeval_max;
} else {
do {
__itimer.it.it_value =
timeval_add(__itimer.it.it_value, __itimer.it.it_interval);
} while (timeval_cmp(now, __itimer.it.it_value) > 0);
waituntil = __itimer.it.it_value;
}
dosignal = true;
}
}
__itimer_unlock();
if (dosignal)
__sig_generate(SIGALRM, SI_TIMER);
__itimer_lock();
struct timespec deadline = timeval_totimespec(waituntil);
_pthread_cond_timedwait(&__itimer.cond, &__itimer.lock, &deadline);
__itimer_unlock();
}
return 0;
}
textwindows static void __itimer_setup(void) {
__itimer.thread = CreateThread(0, STACK_SIZE, __itimer_worker, 0,
kNtStackSizeParamIsAReservation, 0);
}
textwindows int sys_setitimer_nt(int which, const struct itimerval *neu,
struct itimerval *old) {
struct itimerval config;
cosmo_once(&__itimer.once, __itimer_setup);
if (which != ITIMER_REAL || (neu && (!timeval_isvalid(neu->it_value) ||
!timeval_isvalid(neu->it_interval))))
return einval();
if (neu)
// POSIX defines setitimer() with the restrict keyword but let's
// accommodate the usage setitimer(ITIMER_REAL, &it, &it) anyway
config = *neu;
BLOCK_SIGNALS;
__itimer_lock();
if (old) {
old->it_interval = __itimer.it.it_interval;
old->it_value = timeval_subz(__itimer.it.it_value, timeval_real());
}
if (neu) {
if (!timeval_iszero(config.it_value))
config.it_value = timeval_add(config.it_value, timeval_real());
__itimer.it = config;
_pthread_cond_signal(&__itimer.cond);
}
__itimer_unlock();
ALLOW_SIGNALS;
return 0;
}
#endif /* __x86_64__ */