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65 lines
2.0 KiB
65 lines
2.0 KiB
5 years ago
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/*
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* Implementation of a simple circular buffer data structure.
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* Based on the example and guide found here:
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* https://embeddedartistry.com/blog/2017/4/6/circular-buffers-in-cc
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*/
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#ifndef CIRC_BUFF_H_
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#define CIRC_BUFF_H_
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#include <stdbool.h>
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#include "message.h"
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// Circular buffer structure
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typedef struct circ_buf_t circ_buf_t;
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// and handle type
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typedef circ_buf_t *cbuf_handle_t;
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#ifdef TEST //This is a test build
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// Makes private functions reachable by the tester
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#define unit_static
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unit_static void advance_pointer(cbuf_handle_t cbuf);
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unit_static void retreat_pointer(cbuf_handle_t cbuf);
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#else
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#define unit_static static
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#endif
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// Initializes a circular buffer structure and returns the circular buffer handle.
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// Pass in a storage buffer and size.
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cbuf_handle_t circ_buf_init(message_handle_t *buffer, size_t size);
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// Frees a circular buffer structure. Does not free data buffer!
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void circ_buf_free(cbuf_handle_t cbuf);
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// Resets the circular buffer to empty, head == tail. Data not cleared!
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void circ_buf_reset(cbuf_handle_t cbuf);
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// Adds data to the end of the buffer, even if the buffer is full. Old data is overwritten.
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void circ_buf_put(cbuf_handle_t cbuf, const message_handle_t *data);
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// Retrieves a value from the buffer.
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int circ_buf_get(cbuf_handle_t cbuf, message_handle_t *data);
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// Reads a value from the buffer. Does NOT retrieve, size is not reduced!
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int circ_buf_read(cbuf_handle_t cbuf, size_t position, message_handle_t *data);
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// Checks if the buffer is empty.
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bool circ_buf_empty(cbuf_handle_t cbuf);
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// Checks if the buffer is full.
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bool circ_buf_full(cbuf_handle_t cbuf);
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// Returns the capacity of the buffer.
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size_t circ_buf_capacity(cbuf_handle_t cbuf);
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// Returns the number of elements stored in the buffer.
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size_t circ_buf_size(cbuf_handle_t cbuf);
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// Serializes the whole buffer to a single string
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// int circ_buf_serialize(cbuf_handle_t cbuf, char **serialized);
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// De-serializes a string to a buffer
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// int circ_buf_deserialize(cbuf_handle_t cbuf, const char *serialized);
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#endif //CIRC_BUFF_H_
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