los_sem.h

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/*
 * Copyright (c) 2013-2019 Huawei Technologies Co., Ltd. All rights reserved.
 * Copyright (c) 2020-2021 Huawei Device Co., Ltd. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this list of
 *    conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list
 *    of conditions and the following disclaimer in the documentation and/or other materials
 *    provided with the distribution.
 *
 * 3. Neither the name of the copyright holder nor the names of its contributors may be used
 *    to endorse or promote products derived from this software without specific prior written
 *    permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/**
 * @defgroup los_sem Semaphore
 * @ingroup kernel
 */
 
#ifndef _LOS_SEM_H
#define _LOS_SEM_H
 
#include "los_base.h"
#include "los_err.h"
#include "los_list.h"
#include "los_task.h"
 
#ifdef __cplusplus
#if __cplusplus
extern "C" {
#endif /* __cplusplus */
#endif /* __cplusplus */
 
/**
 * @ingroup los_sem
 * Semaphore error code: The memory is insufficient.
 *
 * Value: 0x02000700
 *
 * Solution: Allocate more memory.
 */
#define LOS_ERRNO_SEM_NO_MEMORY  LOS_ERRNO_OS_ERROR(LOS_MOD_SEM, 0x00)
 
/**
 * @ingroup los_sem
 * Semaphore error code: Invalid parameter.
 *
 * Value: 0x02000701
 *
 * Solution: Change the passed-in invalid parameter value to a valid value.
 */
#define LOS_ERRNO_SEM_INVALID      LOS_ERRNO_OS_ERROR(LOS_MOD_SEM, 0x01)
 
/**
 * @ingroup los_sem
 * Semaphore error code: Null pointer.
 *
 * Value: 0x02000702
 *
 * Solution: Change the passed-in null pointer to a valid non-null pointer.
 */
#define LOS_ERRNO_SEM_PTR_NULL     LOS_ERRNO_OS_ERROR(LOS_MOD_SEM, 0x02)
 
/**
 * @ingroup los_sem
 * Semaphore error code: No semaphore control structure is available.
 *
 * Value: 0x02000703
 *
 * Solution: Perform corresponding operations based on the requirements in the code context.
 */
#define LOS_ERRNO_SEM_ALL_BUSY     LOS_ERRNO_OS_ERROR(LOS_MOD_SEM, 0x03)
 
/**
 * @ingroup los_sem
 * Semaphore error code: Invalid parameter that specifies the timeout interval.
 *
 * Value: 0x02000704
 *
 *
 * Solution: Change the passed-in parameter value to a valid nonzero value.
 */
#define LOS_ERRNO_SEM_UNAVAILABLE  LOS_ERRNO_OS_ERROR(LOS_MOD_SEM, 0x04)
 
/**
 * @ingroup los_sem
 * Semaphore error code: The API is called during an interrupt, which is forbidden.
 *
 * Value: 0x02000705
 *
 * Solution: Do not call the API during an interrupt.
 */
#define LOS_ERRNO_SEM_PEND_INTERR  LOS_ERRNO_OS_ERROR(LOS_MOD_SEM, 0x05)
 
/**
 * @ingroup los_sem
 * Semaphore error code: The task is unable to request a semaphore because task scheduling is locked.
 *
 * Value: 0x02000706
 *
 * Solution: Do not call LOS_SemPend when task scheduling is locked.
 */
#define LOS_ERRNO_SEM_PEND_IN_LOCK LOS_ERRNO_OS_ERROR(LOS_MOD_SEM, 0x06)
 
/**
 * @ingroup los_sem
 * Semaphore error code: The request for a semaphore times out.
 *
 * Value: 0x02000707
 *
 * Solution: Change the passed-in parameter value to the value within the valid range.
 */
#define LOS_ERRNO_SEM_TIMEOUT      LOS_ERRNO_OS_ERROR(LOS_MOD_SEM, 0x07)
 
/**
 * @ingroup los_sem
 * Semaphore error code: The times of semaphore release exceed the maximum times permitted.
 *
 * Value: 0x02000708
 *
 * Solution: Perform corresponding operations based on the requirements in the code context.
 */
#define LOS_ERRNO_SEM_OVERFLOW     LOS_ERRNO_OS_ERROR(LOS_MOD_SEM, 0x08)
 
/**
 * @ingroup los_sem
 * Semaphore error code: The queue of the tasks that are waiting on the semaphore control structure is not null.
 *
 * Value: 0x02000709
 *
 * Solution: Delete the semaphore after awaking all tasks that are waiting on the semaphore.
 */
#define LOS_ERRNO_SEM_PENDED       LOS_ERRNO_OS_ERROR(LOS_MOD_SEM, 0x09)
 
/**
* @ingroup los_sem
* Semaphore error code: The API is called in system-level callback, which is forbidden.
*            old usage: The API is called in software timer callback, which is forbidden. (LOS_ERRNO_SEM_PEND_SWTERR)
* Value: 0x0200070A
*
* Solution: Do not call the API during an interrupt.
*/
#define LOS_ERRNO_SEM_PEND_IN_SYSTEM_TASK       LOS_ERRNO_OS_ERROR(LOS_MOD_SEM, 0x0A)
 
/**
 * @ingroup los_sem
 * Maximum number of binary semaphores.
 *
 */
#define OS_SEM_BINARY_COUNT_MAX                 1
 
/**
 * @ingroup los_sem
 * @brief Create a semaphore.
 *
 * @par Description:
 * This API is used to create a semaphore control structure according to the initial number of available semaphores
 * specified by count and return the ID of this semaphore control structure.
 * @attention
 * <ul>
 * <li>None.</li>
 * </ul>
 *
 * @param count       [IN] Initial number of available semaphores. The value range is [0, OS_SEM_COUNT_MAX].
 * @param semHandle   [OUT] ID of the semaphore control structure that is initialized.
 *
 * @retval #LOS_ERRNO_SEM_PTR_NULL  The passed-in semHandle value is NULL.
 * @retval #LOS_ERRNO_SEM_OVERFLOW  The passed-in count value is greater than the maximum number of available
 * semaphores.
 * @retval #LOS_ERRNO_SEM_ALL_BUSY  No semaphore control structure is available.
 * @retval #LOS_OK   The semaphore is successfully created.
 * @par Dependency:
 * <ul><li>los_sem.h: the header file that contains the API declaration.</li></ul>
 * @see LOS_SemDelete
 */
extern UINT32 LOS_SemCreate(UINT16 count, UINT32 *semHandle);
 
/**
 * @ingroup los_sem
 * @brief Create a binary semaphore.
 *
 * @par Description:
 * This API is used to create a binary semaphore control structure according to the initial number of
 * available semaphores specified by count and return the ID of this semaphore control structure.
 * @attention
 * <ul>
 * <li>None.</li>
 * </ul>
 *
 * @param count        [IN] Initial number of available semaphores. The value range is [0, 1].
 * @param semHandle    [OUT] ID of the semaphore control structure that is initialized.
 *
 * @retval #LOS_ERRNO_SEM_PTR_NULL     The passed-in semHandle value is NULL.
 * @retval #LOS_ERRNO_SEM_OVERFLOW     The passed-in count value is greater than the maximum number of
 *                                     available semaphores.
 * @retval #LOS_ERRNO_SEM_ALL_BUSY     No semaphore control structure is available.
 * @retval #LOS_OK   The semaphore is successfully created.
 * @par Dependency:
 * <ul><li>los_sem.h: the header file that contains the API declaration.</li></ul>
 * @see LOS_SemDelete
 */
extern UINT32 LOS_BinarySemCreate(UINT16 count, UINT32 *semHandle);
 
/**
 * @ingroup los_sem
 * @brief Delete a semaphore.
 *
 * @par Description:
 * This API is used to delete a semaphore control structure that has an ID specified by semHandle.
 * @attention
 * <ul>
 * <li>The specified sem id must be created first. </li>
 * </ul>
 *
 * @param semHandle   [IN] ID of the semaphore control structure to be deleted. The ID of the semaphore
 *                           control structure is obtained from semaphore creation.
 *
 * @retval #LOS_ERRNO_SEM_INVALID  The passed-in semHandle value is invalid.
 * @retval #LOS_ERRNO_SEM_PENDED   The queue of the tasks that are waiting on the semaphore control structure is
 * not null.
 * @retval #LOS_OK   The semaphore control structure is successfully deleted.
 * @par Dependency:
 * <ul><li>los_sem.h: the header file that contains the API declaration.</li></ul>
 * @see LOS_SemCreate
 */
extern UINT32 LOS_SemDelete(UINT32 semHandle);
 
/**
 * @ingroup los_sem
 * @brief Request a semaphore.
 *
 * @par Description:
 * This API is used to request a semaphore based on the semaphore control structure ID specified by semHandle and the
 * parameter that specifies the timeout period.
 * @attention
 * <ul>
 * <li>The specified sem id must be created first. </li>
 * <li>Do not call this API in software timer callback. </li>
 * </ul>
 *
 * @param semHandle [IN] ID of the semaphore control structure to be requested. The ID of the semaphore control
 *                         structure is obtained from semaphore creation.
 * @param timeout   [IN] Timeout interval for waiting on the semaphore. The value range is [0, 0xFFFFFFFF].
 *                         If the value is set to 0, the semaphore is not waited on. If the value is set to 0xFFFFFFFF,
 * the semaphore is waited on forever(unit: Tick).
 *
 * @retval #LOS_ERRNO_SEM_INVALID       The passed-in semHandle value is invalid.
 * @retval #LOS_ERRNO_SEM_UNAVAILABLE   There is no available semaphore resource.
 * @retval #LOS_ERRNO_SEM_PEND_INTERR   The API is called during an interrupt, which is forbidden.
 * @retval #LOS_ERRNO_SEM_PEND_IN_LOCK  The task is unable to request a semaphore because task scheduling is locked.
 * @retval #LOS_ERRNO_SEM_TIMEOUT       The request for the semaphore times out.
 * @retval #LOS_OK   The semaphore request succeeds.
 * @par Dependency:
 * <ul><li>los_sem.h: the header file that contains the API declaration.</li></ul>
 * @see LOS_SemPost | LOS_SemCreate
 */
extern UINT32 LOS_SemPend(UINT32 semHandle, UINT32 timeout);
 
/**
 * @ingroup los_sem
 * @brief Release a semaphore.
 *
 * @par Description:
 * This API is used to release a semaphore that has a semaphore control structure ID specified by semHandle.
 * @attention
 * <ul>
 * <li>The specified sem id must be created first. </li>
 * </ul>
 *
 * @param semHandle   [IN] ID of the semaphore control structure to be released.The ID of the semaphore control
 *                         structure is obtained from semaphore creation.
 *
 * @retval #LOS_ERRNO_SEM_INVALID      The passed-in semHandle value is invalid.
 * @retval #LOS_ERRNO_SEM_OVERFLOW     The times of semaphore release exceed the maximum times permitted.
 * @retval #LOS_OK                     The semaphore is successfully released.
 * @par Dependency:
 * <ul><li>los_sem.h: the header file that contains the API declaration.</li></ul>
 * @see LOS_SemPend | LOS_SemCreate
 */
extern UINT32 LOS_SemPost(UINT32 semHandle);
 
#ifdef __cplusplus
#if __cplusplus
}
#endif /* __cplusplus */
#endif /* __cplusplus */
 
#endif /* _LOS_SEM_H */