#include <sys/condvar.h>
#include <sys/spinlock2.h>
#include <sys/systm.h>
#include <sys/lock.h>

void
cv_init(struct cv *c, const char *desc)
{
        c->cv_desc = desc;
        c->cv_waiters = 0;
        spin_init(&c->cv_lock, "cvinit");
}

void
cv_destroy(struct cv *c)
{
        spin_uninit(&c->cv_lock);
}

int
_cv_timedwait(struct cv *c, struct lock *lk, int timo, int wakesig)
{
        int flags = wakesig ? PCATCH : 0;
        int error;

        /*
         * Can interlock without critical section/spinlock as long
         * as we don't block before calling *sleep().  PINTERLOCKED
         * must be passed to the *sleep() to use the manual interlock
         * (else a new one is created which opens a timing race).
         */
        tsleep_interlock(c, flags);

        spin_lock(&c->cv_lock);
        c->cv_waiters++;
        spin_unlock(&c->cv_lock);

        if (lk)
                error = lksleep(c, lk, flags | PINTERLOCKED, c->cv_desc, timo);
        else
                error = tsleep(c, flags | PINTERLOCKED, c->cv_desc, timo);

        return (error);
}

/*
 * _cv_timedwait() implementation using mtx.
 */
int
_cv_mtx_timedwait(struct cv *c, struct mtx *mtx, int timo, int wakesig)
{
        int flags = wakesig ? PCATCH : 0;
        int error;

        /*
         * Can interlock without critical section/spinlock as long
         * as we don't block before calling *sleep().  PINTERLOCKED
         * must be passed to the *sleep() to use the manual interlock
         * (else a new one is created which opens a timing race).
         */
        tsleep_interlock(c, flags);

        spin_lock(&c->cv_lock);
        c->cv_waiters++;
        spin_unlock(&c->cv_lock);

        if (mtx)
                error = mtxsleep(c, mtx, flags | PINTERLOCKED, c->cv_desc, timo);
        else
                error = tsleep(c, flags | PINTERLOCKED, c->cv_desc, timo);

        return (error);
}

void
_cv_signal(struct cv *c, int broadcast)
{
        spin_lock(&c->cv_lock);
        if (c->cv_waiters == 0) {
                spin_unlock(&c->cv_lock);
        } else if (broadcast) {
                c->cv_waiters = 0;
                spin_unlock(&c->cv_lock);       /* must unlock first */
                wakeup(c);
        } else {
                c->cv_waiters--;
                spin_unlock(&c->cv_lock);       /* must unlock first */
                wakeup_one(c);
        }
}

int
cv_has_waiters(const struct cv *c)
{
        return (c->cv_waiters);
}