[wasi-libc.git] / libc-top-half / musl / src / thread / pthread_mutex_unlock.c

#include "pthread_impl.h"

int __pthread_mutex_unlock(pthread_mutex_t *m)
{
	pthread_t self;
	int waiters = m->_m_waiters;
	int cont;
	int type = m->_m_type & 15;
	int priv = (m->_m_type & 128) ^ 128;
	int new = 0;
	int old;

	if (type != PTHREAD_MUTEX_NORMAL) {
		self = __pthread_self();
		old = m->_m_lock;
		int own = old & 0x3fffffff;
		if (own != self->tid)
			return EPERM;
		if ((type&3) == PTHREAD_MUTEX_RECURSIVE && m->_m_count)
			return m->_m_count--, 0;
		if ((type&4) && (old&0x40000000))
			new = 0x7fffffff;
		if (!priv) {
			self->robust_list.pending = &m->_m_next;
#ifdef __wasilibc_unmodified_upstream
			__vm_lock();
#endif
		}
		volatile void *prev = m->_m_prev;
		volatile void *next = m->_m_next;
		*(volatile void *volatile *)prev = next;
		if (next != &self->robust_list.head) *(volatile void *volatile *)
			((char *)next - sizeof(void *)) = prev;
	}
#ifdef __wasilibc_unmodified_upstream
	if (type&8) {
		if (old<0 || a_cas(&m->_m_lock, old, new)!=old) {
			if (new) a_store(&m->_m_waiters, -1);
			__syscall(SYS_futex, &m->_m_lock, FUTEX_UNLOCK_PI|priv);
		}
		cont = 0;
		waiters = 0;
	} else {
		cont = a_swap(&m->_m_lock, new);
	}
#else
		cont = a_swap(&m->_m_lock, new);
#endif
	if (type != PTHREAD_MUTEX_NORMAL && !priv) {
		self->robust_list.pending = 0;
#ifdef __wasilibc_unmodified_upstream
		__vm_unlock();
#endif
	}
	if (waiters || cont<0)
		__wake(&m->_m_lock, 1, priv);
	return 0;
}

weak_alias(__pthread_mutex_unlock, pthread_mutex_unlock);
Commit	Line	Data
320054e8 DG	1	#include "pthread_impl.h"
	2
	3	int __pthread_mutex_unlock(pthread_mutex_t *m)
	4	{
	5	pthread_t self;
	6	int waiters = m->_m_waiters;
	7	int cont;
	8	int type = m->_m_type & 15;
	9	int priv = (m->_m_type & 128) ^ 128;
f41256b6 DG	10	int new = 0;
f41256b6 DG	11	int old;
320054e8 DG	12
	13	if (type != PTHREAD_MUTEX_NORMAL) {
	14	self = __pthread_self();
f41256b6 DG	15	old = m->_m_lock;
	16	int own = old & 0x3fffffff;
	17	if (own != self->tid)
320054e8 DG	18	return EPERM;
	19	if ((type&3) == PTHREAD_MUTEX_RECURSIVE && m->_m_count)
	20	return m->_m_count--, 0;
f41256b6 DG	21	if ((type&4) && (old&0x40000000))
f41256b6 DG	22	new = 0x7fffffff;
320054e8 DG	23	if (!priv) {
320054e8 DG	24	self->robust_list.pending = &m->_m_next;
33c3753c	25	#ifdef __wasilibc_unmodified_upstream
320054e8	26	__vm_lock();
33c3753c	27	#endif
320054e8 DG	28	}
	29	volatile void *prev = m->_m_prev;
	30	volatile void *next = m->_m_next;
	31	(volatile void volatile *)prev = next;
	32	if (next != &self->robust_list.head) (volatile void volatile *)
	33	((char )next - sizeof(void )) = prev;
	34	}
33c3753c	35	#ifdef __wasilibc_unmodified_upstream
f41256b6 DG	36	if (type&8) {
	37	if (old<0 \|\| a_cas(&m->_m_lock, old, new)!=old) {
	38	if (new) a_store(&m->_m_waiters, -1);
	39	__syscall(SYS_futex, &m->_m_lock, FUTEX_UNLOCK_PI\|priv);
	40	}
	41	cont = 0;
	42	waiters = 0;
	43	} else {
	44	cont = a_swap(&m->_m_lock, new);
	45	}
33c3753c AB	46	#else
	47	cont = a_swap(&m->_m_lock, new);
	48	#endif
320054e8 DG	49	if (type != PTHREAD_MUTEX_NORMAL && !priv) {
320054e8 DG	50	self->robust_list.pending = 0;
33c3753c	51	#ifdef __wasilibc_unmodified_upstream
320054e8	52	__vm_unlock();
33c3753c	53	#endif
320054e8 DG	54	}
	55	if (waiters \|\| cont<0)
	56	__wake(&m->_m_lock, 1, priv);
	57	return 0;
	58	}
	59
	60	weak_alias(__pthread_mutex_unlock, pthread_mutex_unlock);