/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Copyright 2025 Oxide Computer Company
 */

#include "lint.h"
#include "thr_uberdata.h"
#include <pthread.h>

/*
 * pthread_mutexattr_init: allocates the mutex attribute object and
 * initializes it with the default values.
 */
#pragma weak _pthread_mutexattr_init = pthread_mutexattr_init
int
pthread_mutexattr_init(pthread_mutexattr_t *attr)
{
        mattr_t *ap;

        if ((ap = lmalloc(sizeof (mattr_t))) == NULL)
                return (ENOMEM);
        ap->pshared = PTHREAD_PROCESS_PRIVATE;
        ap->type = PTHREAD_MUTEX_DEFAULT;
        ap->protocol = PTHREAD_PRIO_NONE;
        ap->robustness = PTHREAD_MUTEX_STALLED;
        attr->__pthread_mutexattrp = ap;
        return (0);
}

/*
 * pthread_mutexattr_destroy: frees the mutex attribute object and
 * invalidates it with NULL value.
 */
int
pthread_mutexattr_destroy(pthread_mutexattr_t *attr)
{
        if (attr == NULL || attr->__pthread_mutexattrp == NULL)
                return (EINVAL);
        lfree(attr->__pthread_mutexattrp, sizeof (mattr_t));
        attr->__pthread_mutexattrp = NULL;
        return (0);
}

/*
 * pthread_mutexattr_setpshared: sets the shared attribute
 * to PTHREAD_PROCESS_PRIVATE or PTHREAD_PROCESS_SHARED.
 * This is equivalent to setting the USYNC_THREAD/USYNC_PROCESS
 * flag in mutex_init().
 */
int
pthread_mutexattr_setpshared(pthread_mutexattr_t *attr, int pshared)
{
        mattr_t *ap;

        if (attr == NULL || (ap = attr->__pthread_mutexattrp) == NULL ||
            (pshared != PTHREAD_PROCESS_PRIVATE &&
            pshared != PTHREAD_PROCESS_SHARED))
                return (EINVAL);
        ap->pshared = pshared;
        return (0);
}

/*
 * pthread_mutexattr_getpshared: gets the shared attribute.
 */
#pragma weak _pthread_mutexattr_getpshared = pthread_mutexattr_getpshared
int
pthread_mutexattr_getpshared(const pthread_mutexattr_t *attr, int *pshared)
{
        mattr_t *ap;

        if (attr == NULL || (ap = attr->__pthread_mutexattrp) == NULL ||
            pshared == NULL)
                return (EINVAL);
        *pshared = ap->pshared;
        return (0);
}

/*
 * pthread_mutexattr_setprioceiling: sets the prioceiling attribute.
 */
int
pthread_mutexattr_setprioceiling(pthread_mutexattr_t *attr, int prioceiling)
{
        const pcclass_t *pccp = get_info_by_policy(SCHED_FIFO);
        mattr_t *ap;

        if (attr == NULL || (ap = attr->__pthread_mutexattrp) == NULL ||
            prioceiling < pccp->pcc_primin || prioceiling > pccp->pcc_primax)
                return (EINVAL);
        ap->prioceiling = prioceiling;
        return (0);
}

/*
 * pthread_mutexattr_getprioceiling: gets the prioceiling attribute.
 */
#pragma weak _pthread_mutexattr_getprioceiling = \
                        pthread_mutexattr_getprioceiling
int
pthread_mutexattr_getprioceiling(const pthread_mutexattr_t *attr, int *ceiling)
{
        mattr_t *ap;

        if (attr == NULL || (ap = attr->__pthread_mutexattrp) == NULL ||
            ceiling == NULL)
                return (EINVAL);
        *ceiling = ap->prioceiling;
        return (0);
}

/*
 * pthread_mutexattr_setprotocol: sets the protocol attribute.
 */
int
pthread_mutexattr_setprotocol(pthread_mutexattr_t *attr, int protocol)
{
        mattr_t *ap;

        if (attr == NULL || (ap = attr->__pthread_mutexattrp) == NULL)
                return (EINVAL);
        if (protocol != PTHREAD_PRIO_NONE &&
            protocol != PTHREAD_PRIO_INHERIT &&
            protocol != PTHREAD_PRIO_PROTECT)
                return (ENOTSUP);
        ap->protocol = protocol;
        return (0);
}

/*
 * pthread_mutexattr_getprotocol: gets the protocol attribute.
 */
#pragma weak _pthread_mutexattr_getprotocol = pthread_mutexattr_getprotocol
int
pthread_mutexattr_getprotocol(const pthread_mutexattr_t *attr, int *protocol)
{
        mattr_t *ap;

        if (attr == NULL || (ap = attr->__pthread_mutexattrp) == NULL ||
            protocol == NULL)
                return (EINVAL);
        *protocol = ap->protocol;
        return (0);
}

/*
 * pthread_mutexattr_setrobust: set the mutex robust attribute.
 * pthread_mutexattr_setrobust_np: the historical name.
 */
#pragma weak pthread_mutexattr_setrobust_np = pthread_mutexattr_setrobust
int
pthread_mutexattr_setrobust(pthread_mutexattr_t *attr, int robust)
{
        mattr_t *ap;

        if (attr == NULL || (ap = attr->__pthread_mutexattrp) == NULL ||
            (robust != PTHREAD_MUTEX_ROBUST && robust != PTHREAD_MUTEX_STALLED))
                return (EINVAL);
        ap->robustness = robust;
        return (0);
}

/*
 * pthread_mutexattr_getrobust: get the mutex robust attribute.
 * pthread_mutexattr_getrobust_np: the historical name.
 */
#pragma weak pthread_mutexattr_getrobust_np = pthread_mutexattr_getrobust
int
pthread_mutexattr_getrobust(const pthread_mutexattr_t *attr, int *robust)
{
        mattr_t *ap;

        if (attr == NULL || (ap = attr->__pthread_mutexattrp) == NULL ||
            robust == NULL)
                return (EINVAL);
        *robust = ap->robustness;
        return (0);
}

/*
 * pthread_mutex_init: Initializes the mutex object.  It copies the various
 * attributes into one type argument and calls mutex_init().  Unlike other
 * values, the types that are used in the mutex attributes are not 1:1 mapped to
 * our underlying lock types at this time so we can properly honor the semantics
 * of someone asking for a PTHREAD_MUTEX_NORMAL lock that must deadlock. The
 * underlying threads implementation does not do this by default for
 * USYNC_THREAD and so we don't do this unless explicitly asked for it.
 */
#pragma weak _pthread_mutex_init = pthread_mutex_init
int
pthread_mutex_init(pthread_mutex_t *_RESTRICT_KYWD mutex,
    const pthread_mutexattr_t *_RESTRICT_KYWD attr)
{
        mattr_t         *ap;
        int             type, ret;
        int             prioceiling = 0;
        uint16_t        flags = 0;

        /*
         * All of the pshared, type, protocol, robust attributes
         * translate to bits in the mutex_type field.
         */
        if (attr != NULL) {
                if ((ap = attr->__pthread_mutexattrp) == NULL)
                        return (EINVAL);
                switch (ap->type) {
                case PTHREAD_MUTEX_NORMAL:
                        type = LOCK_NORMAL;
                        flags = LOCK_DEADLOCK;
                        break;
                case PTHREAD_MUTEX_ERRORCHECK:
                        type = LOCK_ERRORCHECK;
                        break;
                case PTHREAD_MUTEX_RECURSIVE:
                        type = LOCK_RECURSIVE | LOCK_ERRORCHECK;
                        break;
                default:
                        /*
                         * This covers PTHREAD_MUTEX_DEFAULT, which should be
                         * the only remaining valid value.
                         */
                        type = LOCK_NORMAL;
                        break;
                }

                type |= ap->pshared | ap->protocol | ap->robustness;
                if (ap->protocol == PTHREAD_PRIO_PROTECT)
                        prioceiling = ap->prioceiling;
        } else {
                type = PTHREAD_PROCESS_PRIVATE | LOCK_NORMAL |
                    PTHREAD_PRIO_NONE | PTHREAD_MUTEX_STALLED;
        }

        /*
         * POSIX mutexes (this interface) make no guarantee about the state of
         * the mutex before pthread_mutex_init(3C) is called.  Sun mutexes, upon
         * which these are built and which mutex_init(3C) below represents
         * require that a robust mutex be initialized to all 0s _prior_ to
         * mutex_init() being called, and that mutex_init() of an initialized
         * mutex return EBUSY.
         *
         * We respect both these behaviors by zeroing the mutex here in the
         * POSIX implementation if and only if the mutex magic is incorrect,
         * and the mutex is robust.
         */
        if (((type & PTHREAD_MUTEX_ROBUST) != 0) &&
            (((mutex_t *)mutex)->mutex_magic != MUTEX_MAGIC)) {
                (void) memset(mutex, 0, sizeof (*mutex));
        }

        ret = mutex_init((mutex_t *)mutex, type, &prioceiling);

        /*
         * If we have a normal mutex, we need to set that deadlock behavior is
         * required.
         */
        if (ret == 0 && flags != 0) {
                mutex_t *mp = (mutex_t *)mutex;
                mp->mutex_flag |= flags;
        }

        return (ret);
}

/*
 * pthread_mutex_setprioceiling: sets the prioceiling.
 * From the SUSv3 (POSIX) specification for pthread_mutex_setprioceiling():
 *      The process of locking the mutex need not
 *      adhere to the priority protect protocol.
 * We pass the MUTEX_NOCEIL flag to mutex_lock_internal() so that
 * a non-realtime thread can successfully execute this operation.
 */
int
pthread_mutex_setprioceiling(pthread_mutex_t *mutex, int ceil, int *oceil)
{
        mutex_t *mp = (mutex_t *)mutex;
        const pcclass_t *pccp = get_info_by_policy(SCHED_FIFO);
        int error;

        if (!(mp->mutex_type & PTHREAD_PRIO_PROTECT) ||
            ceil < pccp->pcc_primin || ceil > pccp->pcc_primax)
                return (EINVAL);
        error = mutex_lock_internal(mp, NULL, MUTEX_LOCK | MUTEX_NOCEIL);
        if (error == 0 || error == EOWNERDEAD || error == ELOCKUNMAPPED) {
                if (oceil)
                        *oceil = mp->mutex_ceiling;
                mp->mutex_ceiling = ceil;
                error = mutex_unlock_internal(mp, 1);
        }
        return (error);
}

/*
 * pthread_mutex_getprioceiling: gets the prioceiling.
 */
#pragma weak _pthread_mutex_getprioceiling = pthread_mutex_getprioceiling
int
pthread_mutex_getprioceiling(const pthread_mutex_t *mp, int *ceiling)
{
        *ceiling = ((mutex_t *)mp)->mutex_ceiling;
        return (0);
}

/*
 * UNIX98
 * pthread_mutexattr_settype: sets the type attribute
 *
 * Type attributes are kept in terms of POSIX mutex types until the mutex is
 * initialized, after which it is translated into the corresponding underlying
 * lock type.
 */
int
pthread_mutexattr_settype(pthread_mutexattr_t *attr, int type)
{
        mattr_t *ap;

        if (attr == NULL || (ap = attr->__pthread_mutexattrp) == NULL)
                return (EINVAL);
        switch (type) {
        case PTHREAD_MUTEX_NORMAL:
        case PTHREAD_MUTEX_ERRORCHECK:
        case PTHREAD_MUTEX_RECURSIVE:
        case PTHREAD_MUTEX_DEFAULT:
                break;
        default:
                return (EINVAL);
        }
        ap->type = type;
        return (0);
}

/*
 * UNIX98
 * pthread_mutexattr_gettype: gets the type attribute.
 */
int
pthread_mutexattr_gettype(const pthread_mutexattr_t *attr, int *typep)
{
        mattr_t *ap;

        if (attr == NULL || (ap = attr->__pthread_mutexattrp) == NULL ||
            typep == NULL)
                return (EINVAL);
        *typep = ap->type;
        return (0);
}