/***
  This file is part of libsydney.

  Copyright 2007-2008 Lennart Poettering

  libsydney is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as
  published by the Free Software Foundation, either version 2.1 of the
  License, or (at your option) any later version.

  libsydney is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with libsydney. If not, see
  <http://www.gnu.org/licenses/>.
***/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <pthread.h>
#include <errno.h>

#include "malloc.h"
#include "macro.h"
#include "mutex.h"

struct sa_mutex {
    pthread_mutex_t mutex;
};

struct sa_cond {
    pthread_cond_t cond;
};

sa_mutex* sa_mutex_new(sa_bool_t recursive, sa_bool_t inherit_priority) {
    sa_mutex *m;
    pthread_mutexattr_t attr;
    int r;

    sa_assert_se(pthread_mutexattr_init(&attr) == 0);

    if (recursive)
        sa_assert_se(pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE) == 0);

#ifdef HAVE_PTHREAD_PRIO_INHERIT
    if (inherit_priority)
        sa_assert_se(pthread_mutexattr_setprotocol(&attr, PTHREAD_PRIO_INHERIT) == 0);
#endif

    if (!(m = sa_new(sa_mutex, 1)))
        return NULL;

#ifndef HAVE_PTHREAD_PRIO_INHERIT
    sa_assert_se(pthread_mutex_init(&m->mutex, &attr) == 0);

#else
    if ((r = pthread_mutex_init(&m->mutex, &attr))) {

        /* If this failed, then this was probably due to non-available
         * priority inheritance. In which case we fall back to normal
         * mutexes. */
        sa_assert(r == ENOTSUP && inherit_priority);

        sa_assert_se(pthread_mutexattr_setprotocol(&attr, PTHREAD_PRIO_NONE) == 0);
        sa_assert_se(pthread_mutex_init(&m->mutex, &attr) == 0);
    }
#endif

    return m;
}

void sa_mutex_free(sa_mutex *m) {
    sa_assert(m);

    sa_assert_se(pthread_mutex_destroy(&m->mutex) == 0);
    sa_free(m);
}

void sa_mutex_lock(sa_mutex *m) {
    sa_assert(m);

    sa_assert_se(pthread_mutex_lock(&m->mutex) == 0);
}

void sa_mutex_unlock(sa_mutex *m) {
    sa_assert(m);

    sa_assert_se(pthread_mutex_unlock(&m->mutex) == 0);
}

sa_cond *sa_cond_new(void) {
    sa_cond *c;

    if (!(c = sa_new(sa_cond, 1)))
        return NULL;

    sa_assert_se(pthread_cond_init(&c->cond, NULL) == 0);
    return c;
}

void sa_cond_free(sa_cond *c) {
    sa_assert(c);

    sa_assert_se(pthread_cond_destroy(&c->cond) == 0);
    sa_free(c);
}

void sa_cond_signal(sa_cond *c, int broadcast) {
    sa_assert(c);

    if (broadcast)
        sa_assert_se(pthread_cond_broadcast(&c->cond) == 0);
    else
        sa_assert_se(pthread_cond_signal(&c->cond) == 0);
}

int sa_cond_wait(sa_cond *c, sa_mutex *m) {
    sa_assert(c);
    sa_assert(m);

    return pthread_cond_wait(&c->cond, &m->mutex);
}