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#include <time.h>
#include <setjmp.h>
#include "pthread_impl.h"
struct ksigevent {
union sigval sigev_value;
int sigev_signo;
int sigev_notify;
int sigev_tid;
};
struct start_args {
pthread_barrier_t b;
struct sigevent *sev;
};
static void dummy_1(pthread_t self)
{
}
weak_alias(dummy_1, __pthread_tsd_run_dtors);
void __reset_tls();
static void cleanup_fromsig(void *p)
{
pthread_t self = __pthread_self();
__pthread_tsd_run_dtors(self);
self->cancel = 0;
self->cancelbuf = 0;
self->canceldisable = 0;
self->cancelasync = 0;
self->unblock_cancel = 0;
__reset_tls();
longjmp(p, 1);
}
static void timer_handler(int sig, siginfo_t *si, void *ctx)
{
pthread_t self = __pthread_self();
jmp_buf jb;
void (*notify)(union sigval) = (void (*)(union sigval))self->start;
union sigval val = { .sival_ptr = self->start_arg };
if (!setjmp(jb) && si->si_code == SI_TIMER) {
pthread_cleanup_push(cleanup_fromsig, jb);
notify(val);
pthread_cleanup_pop(1);
}
}
static void install_handler()
{
struct sigaction sa = {
.sa_sigaction = timer_handler,
.sa_flags = SA_SIGINFO | SA_RESTART
};
__libc_sigaction(SIGTIMER, &sa, 0);
}
static void *start(void *arg)
{
pthread_t self = __pthread_self();
struct start_args *args = arg;
int id;
/* Reuse no-longer-needed thread structure fields to avoid
* needing the timer address in the signal handler. */
self->start = (void *(*)(void *))args->sev->sigev_notify_function;
self->start_arg = args->sev->sigev_value.sival_ptr;
pthread_barrier_wait(&args->b);
if ((id = self->timer_id) >= 0) {
__syscall(SYS_rt_sigprocmask, SIG_UNBLOCK,
SIGTIMER_SET, 0, _NSIG/8);
__wait(&self->timer_id, 0, id, 1);
__syscall(SYS_timer_delete, id);
}
return 0;
}
int timer_create(clockid_t clk, struct sigevent *restrict evp, timer_t *restrict res)
{
static pthread_once_t once = PTHREAD_ONCE_INIT;
pthread_t td;
pthread_attr_t attr;
int r;
struct start_args args;
struct ksigevent ksev, *ksevp=0;
int timerid;
sigset_t set;
switch (evp ? evp->sigev_notify : SIGEV_SIGNAL) {
case SIGEV_NONE:
case SIGEV_SIGNAL:
if (evp) {
ksev.sigev_value = evp->sigev_value;
ksev.sigev_signo = evp->sigev_signo;
ksev.sigev_notify = evp->sigev_notify;
ksev.sigev_tid = 0;
ksevp = &ksev;
}
if (syscall(SYS_timer_create, clk, ksevp, &timerid) < 0)
return -1;
*res = (void *)(intptr_t)timerid;
break;
case SIGEV_THREAD:
pthread_once(&once, install_handler);
if (evp->sigev_notify_attributes)
attr = *evp->sigev_notify_attributes;
else
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
pthread_barrier_init(&args.b, 0, 2);
args.sev = evp;
__block_app_sigs(&set);
r = pthread_create(&td, &attr, start, &args);
__restore_sigs(&set);
if (r) {
errno = r;
return -1;
}
ksev.sigev_value.sival_ptr = 0;
ksev.sigev_signo = SIGTIMER;
ksev.sigev_notify = 4; /* SIGEV_THREAD_ID */
ksev.sigev_tid = td->tid;
if (syscall(SYS_timer_create, clk, &ksev, &timerid) < 0)
timerid = -1;
td->timer_id = timerid;
pthread_barrier_wait(&args.b);
if (timerid < 0) return -1;
*res = (void *)(INTPTR_MIN | (uintptr_t)td>>1);
break;
default:
errno = EINVAL;
return -1;
}
return 0;
}
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