Diff: nordic/nrf-sdk/app_common/app_fifo.h

Revision:

0:eff01767de02

Child:

37:c29c330d942c

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nordic/nrf-sdk/app_common/app_fifo.h	Wed Mar 26 14:38:17 2014 +0000
@@ -0,0 +1,84 @@
+/* Copyright (c) 2013 Nordic Semiconductor. All Rights Reserved.
+ *
+ * The information contained herein is property of Nordic Semiconductor ASA.
+ * Terms and conditions of usage are described in detail in NORDIC
+ * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
+ *
+ * Licensees are granted free, non-transferable use of the information. NO
+ * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
+ * the file.
+ *
+ */
+
+/**@file
+ *
+ * @defgroup app_fifo FIFO implementation
+ * @{
+ * @ingroup app_common
+ *
+ * @brief FIFO implementation.
+ */
+
+#ifndef APP_FIFO_H__
+#define APP_FIFO_H__
+
+#include <stdint.h>
+#include <stdlib.h>
+#include "nordic_global.h"
+#include "nrf_error.h"
+
+/**@brief A FIFO instance structure. Keeps track of which bytes to read and write next.
+ *        Also it keeps the information about which memory is allocated for the buffer
+ *        and its size. This needs to be initialized by app_fifo_init() before use.
+ */
+typedef struct
+{
+    uint8_t *          p_buf;           /**< Pointer to FIFO buffer memory.                      */
+    uint16_t           buf_size_mask;   /**< Read/write index mask. Also used for size checking. */
+    volatile uint32_t  read_pos;        /**< Next read position in the FIFO buffer.              */
+    volatile uint32_t  write_pos;       /**< Next write position in the FIFO buffer.             */
+} app_fifo_t;
+
+/**@brief Function for initializing the FIFO.
+ *
+ * @param[out] p_fifo   FIFO object.
+ * @param[in]  p_buf    FIFO buffer for storing data. The buffer size has to be a power of two.
+ * @param[in]  buf_size Size of the FIFO buffer provided, has to be a power of 2.
+ *
+ * @retval     NRF_SUCCESS              If initialization was successful.
+ * @retval     NRF_ERROR_NULL           If a NULL pointer is provided as buffer.
+ * @retval     NRF_ERROR_INVALID_LENGTH If size of buffer provided is not a power of two.
+ */
+uint32_t app_fifo_init(app_fifo_t * p_fifo, uint8_t * p_buf, uint16_t buf_size);
+
+/**@brief Function for adding an element to the FIFO.
+ *
+ * @param[in]  p_fifo   Pointer to the FIFO.
+ * @param[in]  byte     Data byte to add to the FIFO.
+ *
+ * @retval     NRF_SUCCESS              If an element has been successfully added to the FIFO.
+ * @retval     NRF_ERROR_NO_MEM         If the FIFO is full.
+ */
+uint32_t app_fifo_put(app_fifo_t * p_fifo, uint8_t byte);
+
+/**@brief Function for getting the next element from the FIFO.
+ *
+ * @param[in]  p_fifo   Pointer to the FIFO.
+ * @param[out] p_byte   Byte fetched from the FIFO.
+ *
+ * @retval     NRF_SUCCESS              If an element was returned.
+ * @retval     NRF_ERROR_NOT_FOUND      If there is no more elements in the queue.
+ */
+uint32_t app_fifo_get(app_fifo_t * p_fifo, uint8_t * p_byte);
+
+/**@brief Function for flushing the FIFO.
+ *
+ * @param[in]  p_fifo   Pointer to the FIFO.
+ *
+ * @retval     NRF_SUCCESS              If the FIFO flushed successfully.
+ */
+uint32_t app_fifo_flush(app_fifo_t * p_fifo);
+
+#endif // APP_FIFO_H__
+
+/** @} */