pthread_cancelable.c [plain text]
#include "resolver.h"
#include "internal.h"
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <signal.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/sysctl.h>
#include <sys/queue.h>
#include <machine/vmparam.h>
#include <mach/vm_statistics.h>
extern int __unix_conforming;
extern int _pthread_cond_wait(pthread_cond_t *cond,
pthread_mutex_t *mutex,
const struct timespec *abstime,
int isRelative,
int isconforming);
extern int __sigwait(const sigset_t *set, int *sig);
extern int __pthread_sigmask(int, const sigset_t *, sigset_t *);
extern int __pthread_markcancel(mach_port_t);
extern int __pthread_canceled(int);
#ifdef VARIANT_CANCELABLE
extern int __semwait_signal(int cond_sem, int mutex_sem, int timeout, int relative, __int64_t tv_sec, __int32_t tv_nsec);
#else
extern int __semwait_signal(int cond_sem, int mutex_sem, int timeout, int relative, __int64_t tv_sec, __int32_t tv_nsec) __asm__("___semwait_signal_nocancel");
#endif
PTHREAD_NOEXPORT
int _pthread_join(pthread_t thread, void **value_ptr, int conforming,
int (*_semwait_signal)(int, int, int, int, __int64_t, __int32_t));
#ifndef VARIANT_CANCELABLE
PTHREAD_ALWAYS_INLINE
static inline int
_pthread_update_cancel_state(pthread_t thread, int mask, int state)
{
int oldstate, newstate;
os_atomic_rmw_loop2o(thread, cancel_state, oldstate, newstate, seq_cst, {
newstate = oldstate;
newstate &= ~mask;
newstate |= state;
});
return oldstate;
}
PTHREAD_NOEXPORT_VARIANT
int
pthread_cancel(pthread_t thread)
{
#if __DARWIN_UNIX03
if (__unix_conforming == 0)
__unix_conforming = 1;
#endif
if (!_pthread_is_valid(thread, 0, NULL)) {
return(ESRCH);
}
if (thread->wqthread != 0) {
return(ENOTSUP);
}
#if __DARWIN_UNIX03
int state = os_atomic_or2o(thread, cancel_state, _PTHREAD_CANCEL_PENDING, relaxed);
if (state & PTHREAD_CANCEL_ENABLE) {
mach_port_t kport = _pthread_kernel_thread(thread);
if (kport) __pthread_markcancel(kport);
}
#else
thread->cancel_state |= _PTHREAD_CANCEL_PENDING;
#endif
return (0);
}
void
pthread_testcancel(void)
{
pthread_t self = pthread_self();
#if __DARWIN_UNIX03
if (__unix_conforming == 0)
__unix_conforming = 1;
_pthread_testcancel(self, 1);
#else
_pthread_testcancel(self, 0);
#endif
}
#ifndef BUILDING_VARIANT
PTHREAD_NOEXPORT_VARIANT
void
_pthread_exit_if_canceled(int error)
{
if (((error & 0xff) == EINTR) && __unix_conforming && (__pthread_canceled(0) == 0)) {
pthread_t self = pthread_self();
if (self != NULL) {
self->cancel_error = error;
}
pthread_exit(PTHREAD_CANCELED);
}
}
PTHREAD_NOEXPORT_VARIANT
void
_pthread_testcancel(pthread_t thread, int isconforming)
{
const int flags = (PTHREAD_CANCEL_ENABLE|_PTHREAD_CANCEL_PENDING);
int state = os_atomic_load2o(thread, cancel_state, seq_cst);
if ((state & flags) == flags) {
pthread_exit(isconforming ? PTHREAD_CANCELED : 0);
}
}
PTHREAD_NOEXPORT
void
_pthread_markcancel_if_canceled(pthread_t thread, mach_port_t kport)
{
const int flags = (PTHREAD_CANCEL_ENABLE|_PTHREAD_CANCEL_PENDING);
int state = os_atomic_or2o(thread, cancel_state,
_PTHREAD_CANCEL_INITIALIZED, relaxed);
if ((state & flags) == flags && __unix_conforming) {
__pthread_markcancel(kport);
}
}
PTHREAD_NOEXPORT
void *
_pthread_get_exit_value(pthread_t thread, int conforming)
{
const int flags = (PTHREAD_CANCEL_ENABLE|_PTHREAD_CANCEL_PENDING);
void *value = thread->exit_value;
if (conforming) {
int state = os_atomic_load2o(thread, cancel_state, seq_cst);
if ((state & flags) == flags) {
value = PTHREAD_CANCELED;
}
}
return value;
}
PTHREAD_NOEXPORT
void
_pthread_setcancelstate_exit(pthread_t thread, void *value_ptr, int conforming)
{
_pthread_update_cancel_state(thread,
_PTHREAD_CANCEL_STATE_MASK | _PTHREAD_CANCEL_TYPE_MASK,
PTHREAD_CANCEL_DISABLE | PTHREAD_CANCEL_DEFERRED);
if (value_ptr == PTHREAD_CANCELED) {
_PTHREAD_LOCK(thread->lock);
thread->detached |= _PTHREAD_WASCANCEL; _PTHREAD_UNLOCK(thread->lock);
}
}
#endif
PTHREAD_ALWAYS_INLINE
static inline int
_pthread_setcancelstate_internal(int state, int *oldstateptr, int conforming)
{
pthread_t self;
switch (state) {
case PTHREAD_CANCEL_ENABLE:
if (conforming) {
__pthread_canceled(1);
}
break;
case PTHREAD_CANCEL_DISABLE:
if (conforming) {
__pthread_canceled(2);
}
break;
default:
return EINVAL;
}
self = pthread_self();
int oldstate = _pthread_update_cancel_state(self, _PTHREAD_CANCEL_STATE_MASK, state);
if (oldstateptr) {
*oldstateptr = oldstate & _PTHREAD_CANCEL_STATE_MASK;
}
if (!conforming) {
_pthread_testcancel(self, 0);
}
return 0;
}
PTHREAD_NOEXPORT_VARIANT
int
pthread_setcancelstate(int state, int *oldstate)
{
#if __DARWIN_UNIX03
if (__unix_conforming == 0) {
__unix_conforming = 1;
}
return (_pthread_setcancelstate_internal(state, oldstate, 1));
#else
return (_pthread_setcancelstate_internal(state, oldstate, 0));
#endif
}
PTHREAD_NOEXPORT_VARIANT
int
pthread_setcanceltype(int type, int *oldtype)
{
pthread_t self;
#if __DARWIN_UNIX03
if (__unix_conforming == 0)
__unix_conforming = 1;
#endif
if ((type != PTHREAD_CANCEL_DEFERRED) &&
(type != PTHREAD_CANCEL_ASYNCHRONOUS))
return EINVAL;
self = pthread_self();
int oldstate = _pthread_update_cancel_state(self, _PTHREAD_CANCEL_TYPE_MASK, type);
if (oldtype) {
*oldtype = oldstate & _PTHREAD_CANCEL_TYPE_MASK;
}
#if !__DARWIN_UNIX03
_pthread_testcancel(self, 0);
#endif
return (0);
}
int
pthread_sigmask(int how, const sigset_t * set, sigset_t * oset)
{
#if __DARWIN_UNIX03
int err = 0;
if (__pthread_sigmask(how, set, oset) == -1) {
err = errno;
}
return(err);
#else
return(__pthread_sigmask(how, set, oset));
#endif
}
#ifndef BUILDING_VARIANT
static void
__posix_join_cleanup(void *arg)
{
pthread_t thread = (pthread_t)arg;
_PTHREAD_LOCK(thread->lock);
thread->joiner = (struct _pthread *)NULL;
_PTHREAD_UNLOCK(thread->lock);
}
PTHREAD_NOEXPORT PTHREAD_NOINLINE
int
_pthread_join(pthread_t thread, void **value_ptr, int conforming,
int (*_semwait_signal)(int, int, int, int, __int64_t, __int32_t))
{
int res = 0;
pthread_t self = pthread_self();
kern_return_t kern_res;
semaphore_t joinsem, death = (semaphore_t)os_get_cached_semaphore();
if (!_pthread_is_valid(thread, PTHREAD_IS_VALID_LOCK_THREAD, NULL)) {
res = ESRCH;
goto out;
}
if (thread->sig != _PTHREAD_SIG) {
res = ESRCH;
} else if ((thread->detached & PTHREAD_CREATE_DETACHED) ||
!(thread->detached & PTHREAD_CREATE_JOINABLE) ||
(thread->joiner != NULL)) {
res = EINVAL;
} else if (thread == self || (self != NULL && self->joiner == thread)) {
res = EDEADLK;
}
if (res != 0) {
_PTHREAD_UNLOCK(thread->lock);
goto out;
}
joinsem = thread->joiner_notify;
if (joinsem == SEMAPHORE_NULL) {
thread->joiner_notify = joinsem = death;
death = MACH_PORT_NULL;
}
thread->joiner = self;
_PTHREAD_UNLOCK(thread->lock);
if (conforming) {
pthread_cleanup_push(__posix_join_cleanup, (void *)thread);
do {
res = _semwait_signal(joinsem, 0, 0, 0, 0, 0);
} while ((res < 0) && (errno == EINTR));
pthread_cleanup_pop(0);
} else {
kern_return_t (*_semaphore_wait)(semaphore_t) =
(void*)_semwait_signal;
do {
kern_res = _semaphore_wait(joinsem);
} while (kern_res != KERN_SUCCESS);
}
os_put_cached_semaphore((os_semaphore_t)joinsem);
res = _pthread_join_cleanup(thread, value_ptr, conforming);
out:
if (death) {
os_put_cached_semaphore(death);
}
return res;
}
#endif
#endif
int
pthread_join(pthread_t thread, void **value_ptr)
{
#if __DARWIN_UNIX03
if (__unix_conforming == 0)
__unix_conforming = 1;
#ifdef VARIANT_CANCELABLE
_pthread_testcancel(pthread_self(), 1);
#endif
return _pthread_join(thread, value_ptr, 1, __semwait_signal);
#else
return _pthread_join(thread, value_ptr, 0, (void*)semaphore_wait);
#endif
}
int
pthread_cond_wait(pthread_cond_t *cond,
pthread_mutex_t *mutex)
{
int conforming;
#if __DARWIN_UNIX03
if (__unix_conforming == 0)
__unix_conforming = 1;
#ifdef VARIANT_CANCELABLE
conforming = 1;
#else
conforming = -1;
#endif
#else
conforming = 0;
#endif
return (_pthread_cond_wait(cond, mutex, (struct timespec *)NULL, 0, conforming));
}
int
pthread_cond_timedwait(pthread_cond_t *cond,
pthread_mutex_t *mutex,
const struct timespec *abstime)
{
int conforming;
#if __DARWIN_UNIX03
if (__unix_conforming == 0)
__unix_conforming = 1;
#ifdef VARIANT_CANCELABLE
conforming = 1;
#else
conforming = -1;
#endif
#else
conforming = 0;
#endif
return (_pthread_cond_wait(cond, mutex, abstime, 0, conforming));
}
int
sigwait(const sigset_t * set, int * sig)
{
#if __DARWIN_UNIX03
int err = 0;
if (__unix_conforming == 0)
__unix_conforming = 1;
#ifdef VARIANT_CANCELABLE
_pthread_testcancel(pthread_self(), 1);
#endif
if (__sigwait(set, sig) == -1) {
err = errno;
#ifdef VARIANT_CANCELABLE
_pthread_testcancel(pthread_self(), 1);
#endif
if (err == EINTR) {
err = 0;
}
}
return(err);
#else
if (__sigwait(set, sig) == -1) {
if (errno != EINTR) {
return -1;
}
}
return 0;
#endif
}