adjust root folder

2019-10-08 23:47:53 -05:00
parent b6fc50ddea
commit a42e8f507c
1258 changed files with 26 additions and 214 deletions
@@ -0,0 +1,96 @@
+/**
+* @file
+* @author Steve Karg
+* @date 2004
+*
+* Generic ring buffer library for deeply embedded system.
+* See the unit tests for usage examples.
+*/
+#ifndef RINGBUF_H
+#define RINGBUF_H
+
+#include <stdint.h>
+#include <stdbool.h>
+
+/**
+* ring buffer power of two alignment macro
+*
+* @{
+*/
+#ifndef NEXT_POWER_OF_2
+#define B2(x)    (   (x) | (   (x) >> 1) )
+#define B4(x)    ( B2(x) | ( B2(x) >> 2) )
+#define B8(x)    ( B4(x) | ( B4(x) >> 4) )
+#define B16(x)   ( B8(x) | ( B8(x) >> 8) )
+#define B32(x)   (B16(x) | (B16(x) >>16) )
+#define NEXT_POWER_OF_2(x) (B32((x)-1) + 1)
+#endif
+/** @} */
+
+/**
+* ring buffer data structure
+*
+* @{
+*/
+struct ring_buffer_t {
+    /** block of memory or array of data */
+    volatile uint8_t *buffer;
+    /** how many bytes for each chunk */
+    unsigned element_size;
+    /** number of chunks of data */
+    unsigned element_count;
+    /** where the writes go */
+    volatile unsigned head;
+    /** where the reads come from */
+    volatile unsigned tail;
+    /* maximum depth reached */
+    volatile unsigned depth;
+};
+typedef struct ring_buffer_t RING_BUFFER;
+/** @} */
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+    unsigned Ringbuf_Count(RING_BUFFER const *b);
+    unsigned Ringbuf_Depth(RING_BUFFER const *b);
+    unsigned Ringbuf_Depth_Reset(RING_BUFFER *b);
+    unsigned Ringbuf_Size(RING_BUFFER const *b);
+    bool Ringbuf_Full(RING_BUFFER const *b);
+    bool Ringbuf_Empty(RING_BUFFER const *b);
+    /* tail */
+    volatile uint8_t *Ringbuf_Peek(RING_BUFFER const *b);
+    bool Ringbuf_Pop(RING_BUFFER * b,
+        uint8_t * data_element);
+    bool Ringbuf_Pop_Element(RING_BUFFER * b,
+        uint8_t * this_element,
+        uint8_t * data_element);
+    bool Ringbuf_Put_Front(RING_BUFFER * b,
+        uint8_t * data_element);
+    /* head */
+    bool Ringbuf_Put(RING_BUFFER * b,
+        uint8_t * data_element);
+    /* pair of functions to use head memory directly */
+    volatile uint8_t *Ringbuf_Data_Peek(RING_BUFFER * b);
+    volatile uint8_t *Ringbuf_Peek_Next(RING_BUFFER const *b,
+        uint8_t * data_element);
+    bool Ringbuf_Data_Put(RING_BUFFER * b, volatile uint8_t *data_element);
+    /* Note: element_count must be a power of two */
+    bool Ringbuf_Init(RING_BUFFER * b,
+        volatile uint8_t * buffer,
+        unsigned element_size,
+        unsigned element_count);
+
+#ifdef TEST
+#include "ctest.h"
+    void testRingBufPowerOfTwo(Test * pTest);
+    void testRingBufSizeSmall(Test * pTest);
+    void testRingBufSizeLarge(Test * pTest);
+    void testRingBufSizeInvalid(Test * pTest);
+#endif
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+#endif