Multi purpose buffer module.

Multipurpose ringbuffer

Since there weren't any ringbuffers available on the internet optimized for 32-Bit ARM operation without unix-calls and dynamic memory... I created one.

This module is a fixed ringbuffer, it does not allocate any memory, it can work as FIFO or LIFO or any other exotic mode depending on your imagination. With a fixed 32Bit element size it is optimized for 32 bit arm processors. Any smaller value will have overhead, any larger value will require a double entry. (not recommended)

I hope you can use it.

Information

This is not a C++ class, it is a C Module. It does work object oriented, however you cannot work on the object, you work with the object.

Import programxIFO_example

Small example for xIFO

Revision:
2:6013f6d867e5
Parent:
0:a04dc0c57d20
--- a/xIFO.h	Mon Oct 28 19:20:00 2013 +0000
+++ b/xIFO.h	Fri Apr 04 21:36:55 2014 +0000
@@ -1,92 +1,545 @@
- 
- /**
+/**
  * @file    xifo.h
- * @brief   xifo circular buffer
- * @details xifo supplies object oriented circular buffer with 32 bit size elements. \n
- *                     To use either as FIFO (First In First Out) or as FILO (First In Last Out)
+ * @brief   xifo circular buffer for all elements
+ * @details xifo supplies object oriented circular buffer with x bit size elements. \n
+ *          To use either as FIFO (First In First Out) or as FILO (First In Last Out)
+ *          Below are defines to disable or enable any xIFO type you like.
  *
- * @author    Jeroen Lodder
- * @date        April 2013
- * @version 2
+ * @author  Jeroen Lodder
+ * @date    March 2014
+ * @version 3
+ * 
+ * Copyright (c) 2014 Jeroen Lodder
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
  *
  * @{
  */
- 
- /**
- *    Code has been tested on Cortex M0 (LPC1114)
- *  Performance table, number of core clocks
- *    Measured with a timer before and after
- *    r1 = timer->TC
- *        test_function 
- *  r2 = timer->TC
- *
- *  Function    Speed        Worst Case
- *
- *  write            69            71
- *  read_mr        59      59
- *  read_lr        63      70
- *  pop_mr        76      78
- *    pop_lr        45      45
- *
- */
-
 #ifndef _xifo_H_
 #define _xifo_H_
-
+ 
 #include <inttypes.h>
 
-#if defined(__arm__)  || defined(__DOXYGEN__)
-#pragma anon_unions                /**< Allow unnamed unions */
+#if !defined(TRUE) || defined(__DOXYGEN__)
+#define TRUE    (1)
+#endif
+#if !defined(FALSE) || defined(__DOXYGEN__)
+#define FALSE   !(TRUE)
+#endif
+ 
+#ifdef __cplusplus
+#if !defined(xIFO_USE_CPP) || defined(__DOXYGEN__)
+#define xIFO_USE_CPP            TRUE
+#endif
+#endif
+
+#if !defined(xIFO_USE_64BIT) || defined(__DOXYGEN__)
+#define xIFO_USE_64BIT          TRUE
+#endif
+
+#if !defined(xIFO_USE_32BIT) || defined(__DOXYGEN__)
+#define xIFO_USE_32BIT          TRUE
+#endif
+
+#if !defined(xIFO_USE_16BIT) || defined(__DOXYGEN__)
+#define xIFO_USE_16BIT          TRUE
+#endif
+
+#if !defined(xIFO_USE_8BIT) || defined(__DOXYGEN__)
+#define xIFO_USE_8BIT           TRUE
 #endif
 
+
+#if xIFO_USE_CPP == TRUE
+/**
+ * @brief   Circular Buffer object.
+ * @details This class holds the object of a circular buffer
+ */
+template <class xifo_dtype>
+class Xifo
+{
+public:
+    /**
+     * @brief   Initialise xifo.
+     * @note    Does not clear memory pool.
+     * @param[in] Number of elements buffer can hold (size).
+     */
+    Xifo(uint32_t size)
+    {
+        startpool = new xifo_dtype[size];
+        endpool         = &startpool[size-1];
+        isize           = size;
+        ifull           = 0;
+        icount           = 0;
+        read            = startpool;
+        pwrite          = startpool;
+    }
+
+    /**
+     * @brief   Initialise xifo.
+     * @note    Does not clear memory pool.
+     * @param[in] Number of elements buffer can hold (size).
+     * @param[in] Start of pre-allocated memory pool.
+     */
+    Xifo(uint32_t size, xifo_dtype *sp)
+    {
+        startpool       = sp;
+        endpool         = &sp[size-1];
+        isize           = size;
+        ifull           = 0;
+        icount            = 0;
+        read            = sp;
+        pwrite          = sp;
+    }
+
+    /**
+     * @brief   Deinitialise (and deallocate) buffer xifo.
+     * @note    Does not clear memory pool.
+     */
+    ~Xifo(void)
+    {
+        if(dynamic){
+            delete startpool;
+        }
+    }
+
+    /**
+     * @brief   Clear buffer memory pool
+     * @note    Must be used on initialised buffer object.
+     * @param[in] c   Pointer to @p xifo_SIZETYPE_t object.
+     */
+    void clear(void)
+    {
+        register xifo_dtype *ptemp = startpool;
+        while(ptemp <= endpool){
+            *ptemp++ = 0;
+        }
+    }
+    
+     /**
+     * @brief   Reset buffer
+     * @note    Must be used on initialised buffer object.
+     * @param[in] c   Pointer to @p xifo_SIZETYPE_t object.
+     */
+    void reset(void)
+    {
+        register xifo_dtype *ptemp = startpool;
+        while(ptemp <= endpool){
+            *ptemp++ = 0;
+        }
+        ifull       = 0;
+        icount      = 0;
+        read        = startpool;
+        pwrite      = startpool;
+    }
+
+    /**
+     * @brief   Write to buffer
+     *
+     * @note    Readpointer is automatically set to the last added element.
+     *
+     * @warning Consider this opertaion as atomic!
+     *
+     * @details Adds a value to the buffer.
+     *                  Automatically overwrites oldest elements when full.
+     *
+     * @param[in] c         Pointer to @p xifo_SIZETYPE_t used for configuration.
+     * @param[in] data  Data to add to buffer
+     *
+     * @return  Number of free buffer elements
+     */
+    uint32_t write(xifo_dtype data)
+    {
+        /* Write data */
+        *pwrite = data;
+        /* Update read pointer to most recent element */
+        read = pwrite;
+        /* Write pointer increment */
+        pwrite += 1;
+        /* Validate pointer */
+        if( pwrite > endpool){
+            /* Exceeded pool boundaries */
+            pwrite = startpool;
+        }
+        /* Update count */
+        icount++;
+        /* Verify full */
+        if( icount >= isize ){
+            ifull = 1;
+            icount = isize;
+        }
+        /* return free elements count */
+        return isize - icount;
+    }
+
+    /**
+     * @brief   Read from buffer (lr) Least Recent oriented (fifo)
+     *
+     * @note    Buffer state will be preserved
+     *
+     * @warning Consider this opertaion as atomic!
+     *
+     * @details Read n elements from the oldest element to the most recent.
+     *                  As for index[0] the least recently added element is returned.
+     *                  And for index[count] the most recent element is returned.
+     *                  This makes it possible to peek in fifo.
+     *
+     * @param[in] c         Pointer to @p xifo_SIZETYPE_t used for configuration.
+     * @param[in] index   Index relative from least recent
+     *
+     * @return  Contents of element or 0 if failed (element can hold 0)
+     */
+    xifo_dtype read_lr(uint32_t index)
+    {
+        register xifo_dtype *ptemp;
+        /* Verify there is valid data to read */
+        if(index+1 > icount){
+            return 0;
+        }
+        /* Calculate index of oldest element */
+        index = (icount-1) - index;
+        /* Set pointer */
+        ptemp = (read) - index;
+        if(ptemp < startpool){
+            /* Exceeded pool boundaries */
+            /* Calculate overshoot (startpool - indexptr) and subtract from end */
+            /* Since one element of overshoot results in end - 1 you would miss the last value */
+            ptemp = (endpool+1) - (startpool - ptemp);
+        }
+        /* Read most recent */
+        return *ptemp;
+    }
+
+    /**
+     * @brief   Pop (lr) least recent from buffer (fifo)
+     *
+     * @note    Buffer state will be altered
+     *
+     * @warning Consider this opertaion as atomic!
+     *
+     * @details Read and remove the least recently added from the buffer.
+     *                  Using this results in a fifo type of buffer.
+     *
+     * @param[in] c Pointer to @p xifo_SIZETYPE_t used for configuration.
+     *
+     * @return  Contents of element or 0 if failed (element can hold 0)
+     */
+    xifo_dtype pop_lr()
+    {
+        register xifo_dtype *ptemp;
+        xifo_dtype temp;
+        /* Verify there is valid data read */
+        if(icount == 0){
+            return 0;
+        }
+        /* Derive least recent buffer element */
+        ptemp = read+1 - icount;
+        /* Validate pointer */
+        if(ptemp < startpool){
+            /* Exceeded pool boundaries */
+            /* Calculate overshoot (startpool - indexptr) and subtract from end */
+            /* Since one element of overshoot results in end - 1 you would miss the last value */
+            ptemp = (endpool+1) - (startpool - ptemp);
+        }
+        /* Read oldest buffer element */
+        /* Read to temp register */
+        temp = *ptemp;
+        /* Empty buffer element */
+        *ptemp = 0;
+        /* Reduce count */
+        icount--;
+        /* Check full flag */
+        if(icount < isize)
+            ifull = 0;
+        return temp;
+    }
+
+    /**
+     * @brief   Read from buffer (mr) Most Recent oriented (filo)
+     *
+     * @note    Buffer state will be preserved
+     *
+     * @warning Consider this opertaion as atomic!
+     *
+     * @details Read n elements back in time.
+     *                  As for index[0] the most recently added element is returned.
+     *                  And for index[count] the oldest element is returned.
+     *                  This makes it possible to keep history. For DSP application.
+     *
+     * @param[in] c         Pointer to @p xifo_SIZETYPE_t used for configuration.
+     * @param[in] index   Index relative from most recent
+     *
+     * @return  Contents of element or 0 if failed (element can hold 0)
+     */
+    xifo_dtype read_mr(uint32_t index)
+    {
+        register xifo_dtype *ptemp;
+        /* Verify there is valid data to read */
+        if(index+1 > icount){
+            return 0;
+        }
+        /* Set pointer */
+        ptemp = read - index;
+        /* Validate pointer */
+        if(ptemp < startpool){
+            /* Exceeded pool boundaries */
+            /* Calculate overshoot (startpool - indexptr) and subtract from end */
+            /* Since one element of overshoot results in end - 1 you would miss the last value */
+            ptemp = (endpool+1) - (startpool - ptemp);
+        }
+        /* Read most recent */
+        return *ptemp;
+    }
+
+    /**
+     * @brief   Pop (mr) most recent from buffer (filo)
+     *
+     * @note    Buffer state will be altered
+     *
+     * @warning Consider this opertaion as atomic!
+     *
+     * @details Read and remove the most recently added from the buffer.
+     *                  Using this results in a stack type of buffer.
+     *
+     * @param[in] c         Pointer to @p xifo_SIZETYPE_t used for configuration.
+     *
+     * @return  Contents of element or 0 if failed (element can hold 0)
+     */
+    xifo_dtype pop_mr()
+    {
+        register xifo_dtype temp;
+        /* Verify there is valid data read */
+        if(icount == 0){
+            return 0;
+        }
+        /* Read */
+        temp = *read;
+        /* Empty */
+        *read = 0;
+        /* Most recent element read, return write pointer */
+        pwrite = read;
+        /* Decrement read pointer */
+        read--;
+        /* Validate pointer */
+        if( read < startpool ){
+            /* Exceeded pool boundaries */
+            read = endpool;
+        }
+        /* Reduce count */
+        icount--;
+        if(icount < isize)
+            ifull = 0;
+        return temp;
+    }
+
+    /* Extractors */
+    uint32_t size(){ return isize; }         /**< @brief   Get buffer size */
+    uint32_t used(){ return icount; }        /**< @brief   Get number of used elements */
+    uint32_t full(){ return ifull; }         /**< @brief   Get full flag */
+    uint32_t free(){ return isize-icount; }   /**< @brief   Get number of free elements */
+private:
+    bool dynamic;
+    xifo_dtype *startpool;         /**< @brief First element in pool */
+    xifo_dtype *endpool;    /**< @brief Last element in pool */
+    xifo_dtype *read;       /**< @brief Read pointer */
+    xifo_dtype *pwrite;     /**< @brief Write pointer */
+    /* Variables: */
+    uint32_t ifull;          /**< @brief Flag indicating buffer is full */
+    uint32_t icount;         /**< @brief Number of elements used */
+    uint32_t isize;          /**< @brief Size of buffer */
+};
+#endif
+
+#if xIFO_USE_64BIT == TRUE
 /**
  * @brief   Circular Buffer object.
  * @details This struct holds the object of a circular buffer
  */
 typedef struct  {
-/* Pointers: */
-        uint32_t *startpool;  /**< @brief First element in pool */
-        uint32_t *endpool;        /**< @brief Last element in pool */
-        uint32_t *read;                /**< @brief Read pointer */
-        uint32_t *write;            /**< @brief Write pointer */
-/* Variables: */
-        uint32_t full;        /**< @brief Flag indicating buffer is full */
-    uint32_t elementcount;/**< @brief Number of elements used */
-        uint32_t size;                /**< @brief Size of buffer */
-/* Locally used in functions to prevent stack use: */
-        /**< @brief union to prevent lvalue typecasting */  
-        union {                         
-            uint32_t temp;            /**< @brief temp variable and padding for even sized block */
-            uint32_t *ptemp;         /**< @brief temp variable and padding for even sized block */
-        };
-}xifo_t;
+    /* Pointers: */
+    uint64_t *startpool;    /**< @brief First element in pool */
+    uint64_t *endpool;      /**< @brief Last element in pool */
+    uint64_t *read;         /**< @brief Read pointer */
+    uint64_t *write;        /**< @brief Write pointer */
+    /* Variables: */
+    uint32_t full;          /**< @brief Flag indicating buffer is full */
+    uint32_t count;         /**< @brief Number of elements used */
+    uint32_t size;          /**< @brief Size of buffer */
+}xifo64_t;
+
+/**< @brief   Circular Buffer memory pool type. */
+typedef uint64_t xifo64_pool_t;
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+/* xifo Common */
+void xifo64_init( xifo64_t *c, uint32_t size, uint64_t *startpool );
+void xifo64_clear( xifo64_t *c );
+uint32_t xifo64_write( xifo64_t *c, uint64_t data );
+/* FIFO use */
+uint64_t xifo64_read_lr( xifo64_t *c, uint32_t index );
+uint64_t xifo64_pop_lr( xifo64_t *c );
+/* LIFO use */
+uint64_t xifo64_read_mr( xifo64_t *c, uint32_t index );
+uint64_t xifo64_pop_mr( xifo64_t *c );
+/* Extractors */
+uint32_t xifo64_get_size( xifo64_t *c );
+uint32_t xifo64_get_used( xifo64_t *c );
+uint32_t xifo64_get_full( xifo64_t *c );
+uint32_t xifo64_get_free( xifo64_t *c );
+#ifdef __cplusplus
+}
+#endif
+#endif
+
+#if xIFO_USE_32BIT == TRUE
 /**
- * @brief   Circular Buffer memory pool type.
+ * @brief   Circular Buffer object.
+ * @details This struct holds the object of a circular buffer
  */
-typedef unsigned int xifo_pool_t;
+typedef struct  {
+    /* Pointers: */
+    uint32_t *startpool;    /**< @brief First element in pool */
+    uint32_t *endpool;      /**< @brief Last element in pool */
+    uint32_t *read;         /**< @brief Read pointer */
+    uint32_t *write;        /**< @brief Write pointer */
+    /* Variables: */
+    uint32_t full;          /**< @brief Flag indicating buffer is full */
+    uint32_t count;         /**< @brief Number of elements used */
+    uint32_t size;          /**< @brief Size of buffer */
+}xifo32_t;
+
+/**< @brief   Circular Buffer memory pool type. */
+typedef uint32_t xifo32_pool_t;
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 /* xifo Common */
-void xifo_init(xifo_t *c, uint32_t size, uint32_t *startpool);
-void xifo_clear(xifo_t *c);
-uint32_t xifo_write(xifo_t *c, uint32_t data);
+void xifo32_init( xifo32_t *c, uint32_t size, uint32_t *startpool );
+void xifo32_clear( xifo32_t *c );
+uint32_t xifo32_write( xifo32_t *c, uint32_t data );
 /* FIFO use */
-uint32_t xifo_read_lr(xifo_t *c, uint32_t index);
-uint32_t xifo_pop_lr(xifo_t *c);
+uint32_t xifo32_read_lr( xifo32_t *c, uint32_t index );
+uint32_t xifo32_pop_lr( xifo32_t *c );
 /* LIFO use */
-uint32_t xifo_read_mr(xifo_t *c, uint32_t index);
-uint32_t xifo_pop_mr(xifo_t *c);
+uint32_t xifo32_read_mr( xifo32_t *c, uint32_t index );
+uint32_t xifo32_pop_mr( xifo32_t *c );
 /* Extractors */
-uint32_t xifo_get_size(xifo_t *c);
-uint32_t xifo_get_used(xifo_t *c);
-uint32_t xifo_get_full(xifo_t *c);
-uint32_t xifo_get_free(xifo_t *c);
+uint32_t xifo32_get_size( xifo32_t *c );
+uint32_t xifo32_get_used( xifo32_t *c );
+uint32_t xifo32_get_full( xifo32_t *c );
+uint32_t xifo32_get_free( xifo32_t *c );
 #ifdef __cplusplus
 }
 #endif
+#endif
+
+#if xIFO_USE_16BIT == TRUE
+/**
+ * @brief   Circular Buffer object.
+ * @details This struct holds the object of a circular buffer
+ */
+typedef struct  {
+    /* Pointers: */
+    uint16_t *startpool;    /**< @brief First element in pool */
+    uint16_t *endpool;      /**< @brief Last element in pool */
+    uint16_t *read;         /**< @brief Read pointer */
+    uint16_t *write;        /**< @brief Write pointer */
+    /* Variables: */
+    uint32_t full;          /**< @brief Flag indicating buffer is full */
+    uint32_t count;         /**< @brief Number of elements used */
+    uint32_t size;          /**< @brief Size of buffer */
+}xifo16_t;
+
+/**
+ * @brief   Circular Buffer memory pool type.
+ */
+typedef uint16_t xifo16_pool_t;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+/* xifo Common */
+void xifo16_init( xifo16_t *c, uint32_t size, uint16_t *startpool);
+void xifo16_clear( xifo16_t *c);
+uint32_t xifo16_write( xifo16_t *c, uint16_t data);
+/* FIFO use */
+uint16_t xifo16_read_lr( xifo16_t *c, uint32_t index);
+uint16_t xifo16_pop_lr( xifo16_t *c);
+/* LIFO use */
+uint16_t xifo16_read_mr( xifo16_t *c, uint32_t index);
+uint16_t xifo16_pop_mr( xifo16_t *c);
+/* Extractors */
+uint32_t xifo16_get_size( xifo16_t *c);
+uint32_t xifo16_get_used( xifo16_t *c);
+uint32_t xifo16_get_full( xifo16_t *c);
+uint32_t xifo16_get_free( xifo16_t *c);
+#ifdef __cplusplus
+}
+#endif
+#endif
+
+#if xIFO_USE_8BIT == TRUE
+/**
+ * @brief   Circular Buffer object.
+ * @details This struct holds the object of a circular buffer
+ */
+typedef struct  {
+    /* Pointers: */
+    uint8_t *startpool;     /**< @brief First element in pool */
+    uint8_t *endpool;       /**< @brief Last element in pool */
+    uint8_t *read;          /**< @brief Read pointer */
+    uint8_t *write;         /**< @brief Write pointer */
+    /* Variables: */
+    uint32_t full;          /**< @brief Flag indicating buffer is full */
+    uint32_t count;         /**< @brief Number of elements used */
+    uint32_t size;          /**< @brief Size of buffer */
+}xifo8_t;
+
+/**< @brief   Circular Buffer memory pool type. */
+typedef uint8_t xifo8_pool_t;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+/* xifo Common */
+void xifo8_init(xifo8_t *c, uint32_t size, uint8_t *startpool );
+void xifo8_clear( xifo8_t *c );
+uint32_t xifo8_write( xifo8_t *c, uint8_t data );
+/* FIFO use */
+uint8_t xifo8_read_lr( xifo8_t *c, uint32_t index );
+uint8_t xifo8_pop_lr( xifo8_t *c );
+/* LIFO use */
+uint8_t xifo8_read_mr( xifo8_t *c, uint32_t index );
+uint8_t xifo8_pop_mr( xifo8_t *c );
+/* Extractors */
+uint32_t xifo8_get_size( xifo8_t *c );
+uint32_t xifo8_get_used( xifo8_t *c );
+uint32_t xifo8_get_full( xifo8_t *c );
+uint32_t xifo8_get_free( xifo8_t *c );
+#ifdef __cplusplus
+}
+#endif
+#endif
+
 #endif //_xifo_H_
 
 /** @} */