aboutsummaryrefslogtreecommitdiffstats
path: root/os/rt/include/chsem.h
diff options
context:
space:
mode:
Diffstat (limited to 'os/rt/include/chsem.h')
-rw-r--r--os/rt/include/chsem.h154
1 files changed, 154 insertions, 0 deletions
diff --git a/os/rt/include/chsem.h b/os/rt/include/chsem.h
new file mode 100644
index 000000000..21ee14293
--- /dev/null
+++ b/os/rt/include/chsem.h
@@ -0,0 +1,154 @@
+/*
+ ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
+ 2011,2012,2013 Giovanni Di Sirio.
+
+ This file is part of ChibiOS/RT.
+
+ ChibiOS/RT 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/RT 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 chsem.h
+ * @brief Semaphores macros and structures.
+ *
+ * @addtogroup semaphores
+ * @{
+ */
+
+#ifndef _CHSEM_H_
+#define _CHSEM_H_
+
+#if CH_CFG_USE_SEMAPHORES || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Module constants. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module pre-compile time settings. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Derived constants and error checks. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module data structures and types. */
+/*===========================================================================*/
+
+/**
+ * @brief Semaphore structure.
+ */
+typedef struct semaphore {
+ threads_queue_t s_queue; /**< @brief Queue of the threads sleeping
+ on this semaphore. */
+ cnt_t s_cnt; /**< @brief The semaphore counter. */
+} semaphore_t;
+
+/*===========================================================================*/
+/* Module macros. */
+/*===========================================================================*/
+
+/**
+ * @brief Data part of a static semaphore initializer.
+ * @details This macro should be used when statically initializing a semaphore
+ * that is part of a bigger structure.
+ *
+ * @param[in] name the name of the semaphore variable
+ * @param[in] n the counter initial value, this value must be
+ * non-negative
+ */
+#define _SEMAPHORE_DATA(name, n) {_threads_queue_t_DATA(name.s_queue), n}
+
+/**
+ * @brief Static semaphore initializer.
+ * @details Statically initialized semaphores require no explicit
+ * initialization using @p chSemInit().
+ *
+ * @param[in] name the name of the semaphore variable
+ * @param[in] n the counter initial value, this value must be
+ * non-negative
+ */
+#define SEMAPHORE_DECL(name, n) semaphore_t name = _SEMAPHORE_DATA(name, n)
+
+/*===========================================================================*/
+/* External declarations. */
+/*===========================================================================*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+ void chSemObjectInit(semaphore_t *sp, cnt_t n);
+ void chSemReset(semaphore_t *sp, cnt_t n);
+ void chSemResetI(semaphore_t *sp, cnt_t n);
+ msg_t chSemWait(semaphore_t *sp);
+ msg_t chSemWaitS(semaphore_t *sp);
+ msg_t chSemWaitTimeout(semaphore_t *sp, systime_t time);
+ msg_t chSemWaitTimeoutS(semaphore_t *sp, systime_t time);
+ void chSemSignal(semaphore_t *sp);
+ void chSemSignalI(semaphore_t *sp);
+ void chSemAddCounterI(semaphore_t *sp, cnt_t n);
+ msg_t chSemSignalWait(semaphore_t *sps, semaphore_t *spw);
+#ifdef __cplusplus
+}
+#endif
+
+/*===========================================================================*/
+/* Module inline functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Decreases the semaphore counter.
+ * @details This macro can be used when the counter is known to be positive.
+ *
+ * @iclass
+ */
+static inline void chSemFastWaitI(semaphore_t *sp) {
+
+ chDbgCheckClassI();
+
+ sp->s_cnt--;
+}
+
+/**
+ * @brief Increases the semaphore counter.
+ * @details This macro can be used when the counter is known to be not
+ * negative.
+ *
+ * @iclass
+ */
+static inline void chSemFastSignalI(semaphore_t *sp) {
+
+ chDbgCheckClassI();
+
+ sp->s_cnt++;
+}
+
+/**
+ * @brief Returns the semaphore counter current value.
+ *
+ * @iclass
+ */
+static inline cnt_t chSemGetCounterI(semaphore_t *sp) {
+
+ chDbgCheckClassI();
+
+ return sp->s_cnt;
+}
+
+#endif /* CH_CFG_USE_SEMAPHORES */
+
+#endif /* _CHSEM_H_ */
+
+/** @} */