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C

/*
ChibiOS - Copyright (C) 2006..2018 Giovanni Di Sirio.
This file is part of ChibiOS.
ChibiOS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file nil/include/chmsg.h
* @brief Nil RTOS synchronous messages header file.
*
* @addtogroup NIL_MESSAGES
* @{
*/
#ifndef CHMSG_H
#define CHMSG_H
#if (CH_CFG_USE_MESSAGES == TRUE) || defined(__DOXYGEN__)
/*===========================================================================*/
/* Module constants. */
/*===========================================================================*/
/*===========================================================================*/
/* Module pre-compile time settings. */
/*===========================================================================*/
/*===========================================================================*/
/* Derived constants and error checks. */
/*===========================================================================*/
/*===========================================================================*/
/* Module data structures and types. */
/*===========================================================================*/
/*===========================================================================*/
/* Module macros. */
/*===========================================================================*/
/**
* @name Macro Functions
* @{
*/
/**
* @brief Suspends the thread and waits for an incoming message.
* @post After receiving a message the function @p chMsgGet() must be
* called in order to retrieve the message and then @p chMsgRelease()
* must be invoked in order to acknowledge the reception and send
* the answer.
* @note If the message is a pointer then you can assume that the data
* pointed by the message is stable until you invoke @p chMsgRelease()
* because the sending thread is suspended until then.
* @note The reference counter of the sender thread is not increased, the
* returned pointer is a temporary reference.
*
* @return A pointer to the thread carrying the message.
*
* @sclass
*/
#define chMsgWaitS() chMsgWaitTimeoutS(TIME_INFINITE)
/**
* @brief Returns the message carried by the specified thread.
* @pre This function must be invoked immediately after exiting a call
* to @p chMsgWait().
*
* @param[in] tp pointer to the thread
* @return The message carried by the sender.
*
* @api
*/
#define chMsgGet(tp) ((tp)->sntmsg)
/**
* @brief Releases the thread waiting on top of the messages queue.
* @pre Invoke this function only after a message has been received
* using @p chMsgWait().
*
* @param[in] tp pointer to the thread
* @param[in] msg message to be returned to the sender
*
* @sclass
*/
#define chMsgReleaseS(tp, msg) do { \
(void) chSchReadyI(tp, msg); \
chSchRescheduleS(); \
} while (false)
/** @} */
/*===========================================================================*/
/* External declarations. */
/*===========================================================================*/
#ifdef __cplusplus
extern "C" {
#endif
msg_t chMsgSend(thread_t *tp, msg_t msg);
thread_t *chMsgWait(void);
thread_t *chMsgWaitTimeout(sysinterval_t timeout);
thread_t *chMsgWaitTimeoutS(sysinterval_t timeout);
void chMsgRelease(thread_t *tp, msg_t msg);
#ifdef __cplusplus
}
#endif
#endif /* CH_CFG_USE_MESSAGES == TRUE */
#endif /* CHMSG_H */
/** @} */