Permalink
Find file Copy path
Fetching contributors…
Cannot retrieve contributors at this time
111 lines (89 sloc) 2.76 KB
/*
* The MIT License (MIT)
*
* Copyright (c) 2014-2018, Erik Moqvist
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
* This file is part of the Simba project.
*/
#include "simba.h"
int sem_module_init(void)
{
return (0);
}
int sem_init(struct sem_t *self_p,
int count,
int count_max)
{
ASSERTN(self_p != NULL, EINVAL);
ASSERTN((count >= 0) && (count <= count_max), EINVAL);
ASSERTN(count_max > 0, EINVAL);
self_p->count = count;
self_p->count_max = count_max;
thrd_prio_list_init(&self_p->waiters);
return (0);
}
int sem_take(struct sem_t *self_p,
struct time_t *timeout_p)
{
ASSERTN(self_p != NULL, EINVAL);
int err = 0;
struct thrd_prio_list_elem_t elem;
sys_lock();
if (self_p->count == self_p->count_max) {
elem.thrd_p = thrd_self();
thrd_prio_list_push_isr(&self_p->waiters, &elem);
err = thrd_suspend_isr(timeout_p);
if (err == -ETIMEDOUT) {
thrd_prio_list_remove_isr(&self_p->waiters, &elem);
}
} else {
self_p->count++;
}
sys_unlock();
return (err);
}
int sem_give(struct sem_t *self_p,
int count)
{
ASSERTN(self_p != NULL, EINVAL);
ASSERTN(count >= 0, EINVAL);
sys_lock();
sem_give_isr(self_p, count);
sys_unlock();
return (0);
}
int sem_give_isr(struct sem_t *self_p,
int count)
{
struct thrd_prio_list_elem_t *elem_p;
self_p->count -= count;
if (self_p->count < 0) {
self_p->count = 0;
}
while ((self_p->count < self_p->count_max)
&& ((elem_p = thrd_prio_list_pop_isr(&self_p->waiters)) != NULL)) {
self_p->count++;
thrd_resume_isr(elem_p->thrd_p, 0);
}
return (0);
}