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Diffstat (limited to 'os/various/tribuf.c')
| -rw-r--r-- | os/various/tribuf.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/os/various/tribuf.c b/os/various/tribuf.c new file mode 100644 index 0000000..80eb258 --- /dev/null +++ b/os/various/tribuf.c @@ -0,0 +1,214 @@ +/*
+ 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.
+*/
+
+#include "osal.h"
+#include "tribuf.h"
+
+/**
+ * @file tribuf.c
+ * @brief Triple buffer handler source.
+ *
+ * @addtogroup TriBuf
+ * @{
+ */
+
+/*===========================================================================*/
+/* Driver local definitions. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver exported variables. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver local variables and types. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver local functions. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver interrupt handlers. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver exported functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Initializes the tribuf handler object.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ * @param[in] front Pointer to the initial front buffer.
+ * @param[in] back Pointer to the initial back buffer.
+ * @param[in] orphan Pointer to the initial orphan buffer.
+ *
+ * @init
+ */
+void tribufObjectInit(tribuf_t *handler, void *front, void *back, void *orphan) {
+
+ handler->front = front;
+ handler->back = back;
+ handler->orphan = orphan;
+#if (TRIBUF_USE_WAIT == TRUE)
+ chSemObjectInit(&handler->ready, (cnt_t)0);
+#else
+ handler->ready = false;
+#endif
+}
+
+/**
+ * @brief Gets the current front buffer.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ * @return Pointer to the current front buffer.
+ *
+ * @api
+ */
+void *tribufGetFront(tribuf_t *handler) {
+
+ void *front;
+
+ osalSysLock();
+ front = tribufGetFrontI(handler);
+ osalSysUnlock();
+ return front;
+}
+
+/**
+ * @brief Swaps the current front buffer.
+ *
+ * @details Exchanges the pointer of the current front buffer, which will be
+ * dismissed, with the pointer of the current orphan buffer, which
+ * holds the content of the new front buffer.
+ *
+ * @pre The orphan buffer holds new data, swapped by the back buffer.
+ * @pre The fron buffer is ready for swap.
+ * @post The orphan buffer can be used as new back buffer in the future.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ *
+ * @iclass
+ */
+void tribufSwapFrontI(tribuf_t *handler) {
+
+ void *front;
+
+ osalDbgCheckClassI();
+
+ front = handler->orphan;
+ handler->orphan = handler->front;
+ handler->front = front;
+}
+
+/**
+ * @brief Swaps the current front buffer.
+ *
+ * @details Exchanges the pointer of the current front buffer, which will be
+ * dismissed, with the pointer of the current orphan buffer, which
+ * holds the content of the new front buffer.
+ *
+ * @pre The orphan buffer holds new data, swapped by the back buffer.
+ * @pre The fron buffer is ready for swap.
+ * @post The orphan buffer can be used as new back buffer in the future.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ *
+ * @api
+ */
+void tribufSwapFront(tribuf_t *handler) {
+
+ osalSysLock();
+ tribufSwapFrontI(handler);
+ osalSysUnlock();
+}
+
+/**
+ * @brief Gets the current back buffer.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ * @return Pointer to the current back buffer.
+ *
+ * @api
+ */
+void *tribufGetBack(tribuf_t *handler) {
+
+ void *back;
+
+ osalSysLock();
+ back = tribufGetBackI(handler);
+ osalSysUnlock();
+ return back;
+}
+
+/**
+ * @brief Swaps the current back buffer.
+ *
+ * @details Exchanges the pointer of the current back buffer, which holds new
+ * useful data, with the pointer of the current orphan buffer.
+ *
+ * @pre The orphan buffer holds no meaningful data.
+ * @post The orphan buffer is candidate for new front buffer.
+ * @post A new front buffer is ready and signaled.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ *
+ * @iclass
+ */
+void tribufSwapBackI(tribuf_t *handler) {
+
+ void *back;
+
+ osalDbgCheckClassI();
+
+ back = handler->orphan;
+ handler->orphan = handler->back;
+ handler->back = back;
+
+#if (TRIBUF_USE_WAIT == TRUE)
+ if (chSemGetCounterI(&handler->ready) < (cnt_t)1)
+ chSemSignalI(&handler->ready);
+#else
+ handler->ready = true;
+#endif
+}
+
+/**
+ * @brief Swaps the current back buffer.
+ *
+ * @details Exchanges the pointer of the current back buffer, which holds new
+ * useful data, with the pointer of the current orphan buffer.
+ *
+ * @pre The orphan buffer holds no meaningful data.
+ * @post The orphan buffer is candidate for new front buffer.
+ * @post A new front buffer is ready and signaled.
+ *
+ * @param[in] handler Pointer to the tribuf handler object.
+ *
+ * @api
+ */
+void tribufSwapBack(tribuf_t *handler) {
+
+ osalSysLock();
+ tribufSwapBackI(handler);
+#if (TRIBUF_USE_WAIT == TRUE)
+ osalOsRescheduleS();
+#endif
+ osalSysUnlock();
+}
+
+/** @} */
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