From 48026bb824fd2d9cfb00ecd040db6ef3a416bae9 Mon Sep 17 00:00:00 2001 From: Clyne Sullivan Date: Fri, 22 Jan 2021 21:43:36 -0500 Subject: upload initial port --- ChibiOS_20.3.2/os/rt/src/chmsg.c | 221 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 221 insertions(+) create mode 100644 ChibiOS_20.3.2/os/rt/src/chmsg.c (limited to 'ChibiOS_20.3.2/os/rt/src/chmsg.c') diff --git a/ChibiOS_20.3.2/os/rt/src/chmsg.c b/ChibiOS_20.3.2/os/rt/src/chmsg.c new file mode 100644 index 0000000..2003dd0 --- /dev/null +++ b/ChibiOS_20.3.2/os/rt/src/chmsg.c @@ -0,0 +1,221 @@ +/* + 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 . +*/ + +/** + * @file rt/src/chmsg.c + * @brief Messages code. + * + * @addtogroup messages + * @details Synchronous inter-thread messages APIs and services. + *

Operation Mode

+ * Synchronous messages are an easy to use and fast IPC mechanism, + * threads can both act as message servers and/or message clients, + * the mechanism allows data to be carried in both directions. Note + * that messages are not copied between the client and server threads + * but just a pointer passed so the exchange is very time + * efficient.
+ * Messages are scalar data types of type @p msg_t that are guaranteed + * to be size compatible with data pointers. Note that on some + * architectures function pointers can be larger that @p msg_t.
+ * Messages are usually processed in FIFO order but it is possible to + * process them in priority order by enabling the + * @p CH_CFG_USE_MESSAGES_PRIORITY option in @p chconf.h.
+ * @pre In order to use the message APIs the @p CH_CFG_USE_MESSAGES option + * must be enabled in @p chconf.h. + * @post Enabling messages requires 6-12 (depending on the architecture) + * extra bytes in the @p thread_t structure. + * @{ + */ + +#include "ch.h" + +#if (CH_CFG_USE_MESSAGES == TRUE) || defined(__DOXYGEN__) + +/*===========================================================================*/ +/* Module exported variables. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Module local types. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Module local variables. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Module local functions. */ +/*===========================================================================*/ + +#if CH_CFG_USE_MESSAGES_PRIORITY == TRUE +#define msg_insert(tp, qp) queue_prio_insert(tp, qp) +#else +#define msg_insert(tp, qp) queue_insert(tp, qp) +#endif + +/*===========================================================================*/ +/* Module exported functions. */ +/*===========================================================================*/ + +/** + * @brief Sends a message to the specified thread. + * @details The sender is stopped until the receiver executes a + * @p chMsgRelease()after receiving the message. + * + * @param[in] tp the pointer to the thread + * @param[in] msg the message + * @return The answer message from @p chMsgRelease(). + * + * @api + */ +msg_t chMsgSend(thread_t *tp, msg_t msg) { + thread_t *ctp = currp; + + chDbgCheck(tp != NULL); + + chSysLock(); + ctp->u.sentmsg = msg; + msg_insert(ctp, &tp->msgqueue); + if (tp->state == CH_STATE_WTMSG) { + (void) chSchReadyI(tp); + } + chSchGoSleepS(CH_STATE_SNDMSGQ); + msg = ctp->u.rdymsg; + chSysUnlock(); + + return msg; +} + +/** + * @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 + */ +thread_t *chMsgWaitS(void) { + thread_t *tp; + + chDbgCheckClassS(); + + if (!chMsgIsPendingI(currp)) { + chSchGoSleepS(CH_STATE_WTMSG); + } + tp = queue_fifo_remove(&currp->msgqueue); + tp->state = CH_STATE_SNDMSG; + + return tp; +} + +/** + * @brief Suspends the thread and waits for an incoming message or a + * timeout to occur. + * @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. + * + * @param[in] timeout the number of ticks before the operation timeouts, + * the following special values are allowed: + * - @a TIME_INFINITE no timeout. + * . + * @return A pointer to the thread carrying the message. + * @retval NULL if a timeout occurred. + * + * @sclass + */ +thread_t *chMsgWaitTimeoutS(sysinterval_t timeout) { + thread_t *tp; + + chDbgCheckClassS(); + + if (!chMsgIsPendingI(currp)) { + if (chSchGoSleepTimeoutS(CH_STATE_WTMSG, timeout) != MSG_OK) { + return NULL; + } + } + tp = queue_fifo_remove(&currp->msgqueue); + tp->state = CH_STATE_SNDMSG; + + return tp; +} + +/** + * @brief Poll to check for an incoming message. + * @post If a message is available 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 Result of the poll. + * @retval NULL if no incoming message waiting. + * + * @sclass + */ +thread_t *chMsgPollS(void) { + thread_t *tp = NULL; + + if (chMsgIsPendingI(currp)) { + tp = queue_fifo_remove(&currp->msgqueue); + tp->state = CH_STATE_SNDMSG; + } + + return tp; +} + +/** + * @brief Releases a sender thread specifying a response message. + * @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 + * + * @api + */ +void chMsgRelease(thread_t *tp, msg_t msg) { + + chSysLock(); + chDbgAssert(tp->state == CH_STATE_SNDMSG, "invalid state"); + chMsgReleaseS(tp, msg); + chSysUnlock(); +} + +#endif /* CH_CFG_USE_MESSAGES == TRUE */ + +/** @} */ -- cgit v1.2.3