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Diffstat (limited to 'os/various/tribuf.h')
| -rw-r--r-- | os/various/tribuf.h | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/os/various/tribuf.h b/os/various/tribuf.h new file mode 100644 index 0000000..4ba3f25 --- /dev/null +++ b/os/various/tribuf.h @@ -0,0 +1,225 @@ +/*
+ Copyright (C) 2014..2015 Andrea Zoppi
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+/**
+ * @file tribuf.h
+ * @brief Triple buffer handler header.
+ *
+ * @addtogroup TriBuf
+ * @{
+ */
+
+#ifndef _TRIBUF_H_
+#define _TRIBUF_H_
+
+/*===========================================================================*/
+/* Driver constants. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver pre-compile time settings. */
+/*===========================================================================*/
+
+/**
+ * @name Triple buffer configuration options
+ * @{
+ */
+
+/**
+ * @brief Triple buffers use blocking functions.
+ */
+#if !defined(TRIBUF_USE_WAIT) || defined(__DOXYGEN__)
+#define TRIBUF_USE_WAIT TRUE
+#endif
+
+/** @} */
+
+/*===========================================================================*/
+/* Derived constants and error checks. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver data structures and types. */
+/*===========================================================================*/
+
+/**
+ * @brief Triple buffer handler object.
+ */
+typedef struct {
+ void *front; /**< @brief Current front buffer pointer.*/
+ void *back; /**< @brief Current back buffer pointer.*/
+ void *orphan; /**< @brief Current orphan buffer pointer.*/
+#if (TRIBUF_USE_WAIT == TRUE)
+ semaphore_t ready; /**< @brief A new front buffer is ready.*/
+#else
+ bool ready; /**< @brief A new front buffer is ready.*/
+#endif
+} tribuf_t;
+
+/*===========================================================================*/
+/* Driver macros. */
+/*===========================================================================*/
+
+/**
+ * @brief Checks if a new front buffer is ready.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ * @return Availability of a new front buffer.
+ *
+ * @iclass
+ */
+static inline
+bool tribufIsReadyI(tribuf_t *handler)
+{
+ osalDbgCheckClassI();
+
+#if (TRIBUF_USE_WAIT == TRUE)
+ return (0 != chSemGetCounterI(&handler->ready));
+#else
+ return handler->ready;
+#endif
+}
+
+#if (TRIBUF_USE_WAIT == TRUE) || defined(__DOXYGEN__)
+
+/**
+ * @brief Waits until a new front buffer is ready, with timeout.
+ *
+ * @post The ready signal, result of the back buffer swap, is consumed.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ * @param[in] timeout Timeout of the wait operation.
+ * @return Timeout error code, as from @p chSemWaitTimeoutS.
+ *
+ * @see chSemWaitTimeoutS
+ * @sclass
+ */
+static inline
+msg_t tribufWaitReadyTimeoutS(tribuf_t *handler, systime_t timeout)
+{
+ osalDbgCheckClassS();
+
+ return chSemWaitTimeoutS(&handler->ready, timeout);
+}
+
+/**
+ * @brief Waits until a new front buffer is ready, with timeout.
+ *
+ * @post The ready signal, result of the back buffer swap, is consumed.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ * @param[in] timeout Timeout of the wait operation.
+ * @return Timeout error code, as from @p chSemWaitTimeout.
+ *
+ * @see chSemWaitTimeout
+ * @api
+ */
+static inline
+msg_t tribufWaitReadyTimeout(tribuf_t *handler, systime_t timeout)
+{
+ return chSemWaitTimeout(&handler->ready, timeout);
+}
+
+/**
+ * @brief Waits until a new front buffer is ready.
+ *
+ * @post The ready signal, result of the back buffer swap, is consumed.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ * @return Timeout error code, as from @p chSemWaitS.
+ *
+ * @see chSemWaitS
+ * @sclass
+ */
+static inline
+void tribufWaitReadyS(tribuf_t *handler)
+{
+ osalDbgCheckClassS();
+
+ chSemWaitS(&handler->ready);
+}
+
+/**
+ * @brief Waits until a new front buffer is ready.
+ *
+ * @post The ready signal, result of the back buffer swap, is consumed.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ * @return Timeout error code, as from @p chSemWait.
+ *
+ * @see chSemWait
+ * @api
+ */
+static inline
+void tribufWaitReady(tribuf_t *handler)
+{
+ chSemWait(&handler->ready);
+}
+
+#endif /* (TRIBUF_USE_WAIT == TRUE) || defined(__DOXYGEN__) */
+
+/**
+ * @brief Gets the current front buffer.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ * @return Pointer to the current front buffer.
+ *
+ * @iclass
+ */
+static inline
+void *tribufGetFrontI(tribuf_t *handler) {
+
+ osalDbgCheckClassI();
+
+ return handler->front;
+}
+
+/**
+ * @brief Gets the current back buffer.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ * @return Pointer to the current back buffer.
+ *
+ * @iclass
+ */
+static inline
+void *tribufGetBackI(tribuf_t *handler) {
+
+ osalDbgCheckClassI();
+
+ return handler->back;
+}
+
+/*===========================================================================*/
+/* External declarations. */
+/*===========================================================================*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+ void tribufObjectInit(tribuf_t *handler, void *front, void *back, void *orphan);
+ void *tribufGetFront(tribuf_t *handler);
+ void tribufSwapFrontI(tribuf_t *handler);
+ void tribufSwapFront(tribuf_t *handler);
+ void *tribufGetBack(tribuf_t *handler);
+ void tribufSwapBackI(tribuf_t *handler);
+ void tribufSwapBack(tribuf_t *handler);
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _TRIBUF_H_ */
+/** @} */
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