From 016a5dc1925a66c7d1ffc14b862b1342f399cfda Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Thu, 14 Apr 2011 12:51:00 -0400 Subject: use a separate signal from SIGCANCEL for SIGEV_THREAD timers otherwise we cannot support an application's desire to use asynchronous cancellation within the callback function. this change also slightly debloats pthread_create.c. --- src/time/timer_create.c | 32 +++++++++++++++++++++++++------- 1 file changed, 25 insertions(+), 7 deletions(-) (limited to 'src/time') diff --git a/src/time/timer_create.c b/src/time/timer_create.c index c107e150..cc10bef0 100644 --- a/src/time/timer_create.c +++ b/src/time/timer_create.c @@ -21,22 +21,38 @@ weak_alias(dummy_1, __pthread_tsd_run_dtors); static void cleanup_fromsig(void *p) { pthread_t self = __pthread_self(); + __pthread_tsd_run_dtors(self); self->cancel = 0; self->cancelbuf = 0; - __pthread_tsd_run_dtors(self); + self->canceldisable = 0; + self->cancelasync = 0; + self->unblock_cancel = 0; longjmp(p, 1); } -void __sigtimer_handler(pthread_t self) +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)) return; - pthread_cleanup_push(cleanup_fromsig, jb); - notify(val); - pthread_cleanup_pop(0); + if (!setjmp(jb) && si->si_code == SI_TIMER) { + pthread_cleanup_push(cleanup_fromsig, jb); + notify(val); + pthread_cleanup_pop(0); + } +} + +static void install_handler() +{ + struct sigaction sa = { + .sa_sigaction = timer_handler, + .sa_flags = SA_SIGINFO | SA_RESTART + }; + __libc_sigaction(SIGTIMER, &sa, 0); + sigaddset(&sa.sa_mask, SIGTIMER); + __libc_sigprocmask(SIG_UNBLOCK, &sa.sa_mask, 0); } static void *start(void *arg) @@ -58,6 +74,7 @@ static void *start(void *arg) int timer_create(clockid_t clk, struct sigevent *evp, timer_t *res) { + static pthread_once_t once = PTHREAD_ONCE_INIT; pthread_t td; pthread_attr_t attr; int r; @@ -80,6 +97,7 @@ int timer_create(clockid_t clk, struct sigevent *evp, timer_t *res) *res = (void *)timerid; break; case SIGEV_THREAD: + pthread_once(&once, install_handler); if (evp->sigev_notify_attributes) attr = *evp->sigev_notify_attributes; else @@ -93,7 +111,7 @@ int timer_create(clockid_t clk, struct sigevent *evp, timer_t *res) return -1; } ksev.sigev_value.sival_ptr = 0; - ksev.sigev_signo = SIGCANCEL; + ksev.sigev_signo = SIGTIMER; ksev.sigev_notify = 4; /* SIGEV_THREAD_ID */ ksev.sigev_tid = td->tid; r = syscall(SYS_timer_create, clk, &ksev, &timerid); -- cgit v1.2.1