rt-thread-official/components/libc/posix/pthreads/pthread_tls.c

/*
 * Copyright (c) 2006-2021, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2010-10-26     Bernard      the first version
 */

#include <pthread.h>
#include "pthread_internal.h"

_pthread_key_data_t _thread_keys[PTHREAD_KEY_MAX];

/* initialize key area */
static int pthread_key_system_init(void)
{
    rt_memset(&_thread_keys[0], 0, sizeof(_thread_keys));
    return 0;
}
INIT_COMPONENT_EXPORT(pthread_key_system_init);

void *pthread_getspecific(pthread_key_t key)
{
    struct _pthread_data* ptd;

    if (rt_thread_self() == NULL) return NULL;

    /* get pthread data from user data of thread */
    ptd = (_pthread_data_t *)rt_thread_self()->user_data;
    RT_ASSERT(ptd != NULL);

    if (ptd->tls == NULL)
        return NULL;

    if ((key < PTHREAD_KEY_MAX) && (_thread_keys[key].is_used))
        return ptd->tls[key];

    return NULL;
}
RTM_EXPORT(pthread_getspecific);

int pthread_setspecific(pthread_key_t key, const void *value)
{
    struct _pthread_data* ptd;

    if (rt_thread_self() == NULL) return EINVAL;

    /* get pthread data from user data of thread */
    ptd = (_pthread_data_t *)rt_thread_self()->user_data;
    RT_ASSERT(ptd != NULL);

    /* check tls area */
    if (ptd->tls == NULL)
    {
        ptd->tls = (void**)rt_malloc(sizeof(void*) * PTHREAD_KEY_MAX);
    }

    if ((key < PTHREAD_KEY_MAX) && _thread_keys[key].is_used)
    {
        ptd->tls[key] = (void *)value;

        return 0;
    }

    return EINVAL;
}
RTM_EXPORT(pthread_setspecific);

int pthread_key_create(pthread_key_t *key, void (*destructor)(void*))
{
    rt_uint32_t index;

    rt_enter_critical();
    for (index = 0; index < PTHREAD_KEY_MAX; index ++)
    {
        if (_thread_keys[index].is_used == 0)
        {
            _thread_keys[index].is_used = 1;
            _thread_keys[index].destructor = destructor;

            *key = index;

            rt_exit_critical();

            return 0;
        }
    }

    rt_exit_critical();

    return EAGAIN;
}
RTM_EXPORT(pthread_key_create);

int pthread_key_delete(pthread_key_t key)
{
    if (key >= PTHREAD_KEY_MAX)
        return EINVAL;

    rt_enter_critical();
    _thread_keys[key].is_used = 0;
    _thread_keys[key].destructor = 0;
    rt_exit_critical();

    return 0;
}
RTM_EXPORT(pthread_key_delete);