ringbuf.h

/*####COPYRIGHTBEGIN####
 -------------------------------------------
 Copyright (C) 2004 by Steve Karg

 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License
 as published by the Free Software Foundation; either version 2
 of the License, or (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

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 along with this program; if not, write to:
 The Free Software Foundation, Inc.
 59 Temple Place - Suite 330
 Boston, MA  02111-1307
 USA.

 As a special exception, if other files instantiate templates or
 use macros or inline functions from this file, or you compile
 this file and link it with other works to produce a work based
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 work to be covered by the GNU General Public License. However
 the source code for this file must still be made available in
 accordance with section (3) of the GNU General Public License.

 This exception does not invalidate any other reasons why a work
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####COPYRIGHTEND####*/

/* Functional Description: 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>

struct ring_buffer_t {
    uint8_t *data; /* block of memory or array of data */
    unsigned element_size;      /* how many bytes for each chunk */
    unsigned element_count;     /* number of chunks of data */
    unsigned head; /* where the writes go */
    unsigned tail; /* where the reads come from */
};
typedef struct ring_buffer_t RING_BUFFER;

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

    bool Ringbuf_Empty(
        RING_BUFFER const *b);
    uint8_t *Ringbuf_Get_Front(
        RING_BUFFER const *b);
    uint8_t *Ringbuf_Pop_Front(
        RING_BUFFER * b);
    bool Ringbuf_Put(
        RING_BUFFER * b,        /* ring buffer structure */
        uint8_t *data_element);    /* one element to add to the ring */
    /* Note: element_count should be a power of two,
       or it will only use the next lower power of two */
    void Ringbuf_Init(
        RING_BUFFER * b,        /* ring buffer structure */
        uint8_t *data,     /* data block or array of data */
        unsigned element_size,  /* size of one element in the data block */
        unsigned element_count);        /* number of elements in the data block */

#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif