MultiTech / MTS-Utils

Utility library for MTS Socket Modem Arduino Shield devices from Multi-Tech Systems

Dependents:   mtsas mtsas thermostat_fan_demo--fan mtsas ... more

NOTE: MTS-Utils has moved to GitHub. This version will not be updated. For updates, go to the GitHub version.

MTSCircularBuffer.h@6:fca9bc67b15f, 2014-05-20 (annotated)

Committer:
Mike Fiore
Date:
Tue May 20 16:12:41 2014 -0500
Revision:
6:fca9bc67b15f
Parent:
5:48d0ea2fe332 
include mbed.h in cpp files

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Mike Fiore 3:08a693917d8c 1 #ifndef MTSCIRCULARBUFFER_H
Mike Fiore 3:08a693917d8c 2 #define MTSCIRCULARBUFFER_H
Mike Fiore 3:08a693917d8c 3
Mike Fiore 5:48d0ea2fe332 4 #include "Utils.h"
Mike Fiore 3:08a693917d8c 5
Mike Fiore 3:08a693917d8c 6 namespace mts
Mike Fiore 3:08a693917d8c 7 {
Mike Fiore 3:08a693917d8c 8
Mike Fiore 3:08a693917d8c 9 /** This class provides a circular byte buffer meant for temporary storage
Mike Fiore 3:08a693917d8c 10 * during IO transactions. It contains many of the common methods you
Mike Fiore 3:08a693917d8c 11 * would expect from a circular buffer like read, write, and various
Mike Fiore 3:08a693917d8c 12 * methods for checking the size or status. It should be noted that
Mike Fiore 3:08a693917d8c 13 * this class does not include any special code for thread safety like
Mike Fiore 3:08a693917d8c 14 * a lock. In most cases this is not problematic, but is something
Mike Fiore 3:08a693917d8c 15 * to be aware of.
Mike Fiore 3:08a693917d8c 16 */
Mike Fiore 3:08a693917d8c 17 class MTSCircularBuffer
Mike Fiore 3:08a693917d8c 18 {
Mike Fiore 3:08a693917d8c 19 public:
Mike Fiore 3:08a693917d8c 20 /** Creates an MTSCircularBuffer object with the specified static size.
Mike Fiore 3:08a693917d8c 21 *
Mike Fiore 3:08a693917d8c 22 * @prarm bufferSize size of the buffer in bytes.
Mike Fiore 3:08a693917d8c 23 */
Mike Fiore 3:08a693917d8c 24 MTSCircularBuffer(int bufferSize);
Mike Fiore 3:08a693917d8c 25
Mike Fiore 3:08a693917d8c 26 /** Destructs an MTSCircularBuffer object and frees all related resources.
Mike Fiore 3:08a693917d8c 27 */
Mike Fiore 3:08a693917d8c 28 ~MTSCircularBuffer();
Mike Fiore 3:08a693917d8c 29
Mike Fiore 3:08a693917d8c 30 /** This method enables bulk reads from the buffer. If more data is
Mike Fiore 3:08a693917d8c 31 * requested then available it simply returns all remaining data within the
Mike Fiore 3:08a693917d8c 32 * buffer.
Mike Fiore 3:08a693917d8c 33 *
Mike Fiore 3:08a693917d8c 34 * @param data the buffer where data read will be added to.
Mike Fiore 3:08a693917d8c 35 * @param length the amount of data in bytes to be read into the buffer.
Mike Fiore 3:08a693917d8c 36 * @returns the total number of bytes that were read.
Mike Fiore 3:08a693917d8c 37 */
Mike Fiore 3:08a693917d8c 38 int read(char* data, int length);
Mike Fiore 3:08a693917d8c 39
Mike Fiore 3:08a693917d8c 40 /** This method reads a single byte from the buffer.
Mike Fiore 3:08a693917d8c 41 *
Mike Fiore 3:08a693917d8c 42 * @param data char where the read byte will be stored.
Mike Fiore 3:08a693917d8c 43 * @returns 1 if byte is read or 0 if no bytes available.
Mike Fiore 3:08a693917d8c 44 */
Mike Fiore 3:08a693917d8c 45 int read(char& data);
Mike Fiore 3:08a693917d8c 46
Mike Fiore 3:08a693917d8c 47 /** This method enables bulk writes to the buffer. If more data
Mike Fiore 3:08a693917d8c 48 * is requested to be written then space available the method writes
Mike Fiore 3:08a693917d8c 49 * as much data as possible and returns the actual amount written.
Mike Fiore 3:08a693917d8c 50 *
Mike Fiore 3:08a693917d8c 51 * @param data the byte array to be written.
Mike Fiore 3:08a693917d8c 52 * @param length the length of data to be written from the data paramter.
Mike Fiore 3:08a693917d8c 53 * @returns the number of bytes written to the buffer, which is 0 if
Mike Fiore 3:08a693917d8c 54 * the buffer is full.
Mike Fiore 3:08a693917d8c 55 */
Mike Fiore 3:08a693917d8c 56 int write(const char* data, int length);
Mike Fiore 3:08a693917d8c 57
Mike Fiore 3:08a693917d8c 58 /** This method writes a signle byte as a char to the buffer.
Mike Fiore 3:08a693917d8c 59 *
Mike Fiore 3:08a693917d8c 60 * @param data the byte to be written as a char.
Mike Fiore 3:08a693917d8c 61 * @returns 1 if the byte was written or 0 if the buffer was full.
Mike Fiore 3:08a693917d8c 62 */
Mike Fiore 3:08a693917d8c 63 int write(char data);
Mike Fiore 3:08a693917d8c 64
Mike Fiore 3:08a693917d8c 65 /** This method is used to setup a callback funtion when the buffer reaches
Mike Fiore 3:08a693917d8c 66 * a certain threshold. The threshold condition is checked after every read
Mike Fiore 3:08a693917d8c 67 * and write call is completed. The condition is made up of both a threshold
Mike Fiore 3:08a693917d8c 68 * value and operator. An example that would trigger a callback is if the
Mike Fiore 3:08a693917d8c 69 * threshold was 10, the operator GREATER, and there were 12 bytes added to an
Mike Fiore 3:08a693917d8c 70 * empty buffer.
Mike Fiore 3:08a693917d8c 71 *
Mike Fiore 3:08a693917d8c 72 * @param tptr a pointer to the object to be called when the condition is met.
Mike Fiore 3:08a693917d8c 73 * @param mptr a pointer to the function within the object to be called when
Mike Fiore 3:08a693917d8c 74 * the condition is met.
Mike Fiore 3:08a693917d8c 75 * @param threshold the value in bytes to be used as part of the condition.
Mike Fiore 3:08a693917d8c 76 * @param op the operator to be used in conjunction with the threshold
Mike Fiore 3:08a693917d8c 77 * as part of the condition.
Mike Fiore 3:08a693917d8c 78 */
Mike Fiore 3:08a693917d8c 79 template<typename T>
Mike Fiore 3:08a693917d8c 80 void attach(T *tptr, void( T::*mptr)(void), int threshold, RelationalOperator op) {
Mike Fiore 3:08a693917d8c 81 _threshold = threshold;
Mike Fiore 3:08a693917d8c 82 _op = op;
Mike Fiore 3:08a693917d8c 83 notify.attach(tptr, mptr);
Mike Fiore 3:08a693917d8c 84 }
Mike Fiore 3:08a693917d8c 85
Mike Fiore 3:08a693917d8c 86 /** This method is used to setup a callback funtion when the buffer reaches
Mike Fiore 3:08a693917d8c 87 * a certain threshold. The threshold condition is checked after every read
Mike Fiore 3:08a693917d8c 88 * and write call is completed. The condition is made up of both a threshold
Mike Fiore 3:08a693917d8c 89 * value and operator. An example that would trigger a callback is if the
Mike Fiore 3:08a693917d8c 90 * threshold was 10, the operator GREATER, and there were 12 bytes added to an
Mike Fiore 3:08a693917d8c 91 * empty buffer.
Mike Fiore 3:08a693917d8c 92 *
Mike Fiore 3:08a693917d8c 93 * @param fptr a pointer to the static function to be called when the condition
Mike Fiore 3:08a693917d8c 94 * is met.
Mike Fiore 3:08a693917d8c 95 * @param threshold the value in bytes to be used as part of the condition.
Mike Fiore 3:08a693917d8c 96 * @param op the operator to be used in conjunction with the threshold
Mike Fiore 3:08a693917d8c 97 * as part of the condition.
Mike Fiore 3:08a693917d8c 98 */
Mike Fiore 3:08a693917d8c 99 void attach(void(*fptr)(void), int threshold, RelationalOperator op) {
Mike Fiore 3:08a693917d8c 100 _threshold = threshold;
Mike Fiore 3:08a693917d8c 101 _op = op;
Mike Fiore 3:08a693917d8c 102 notify.attach(fptr);
Mike Fiore 3:08a693917d8c 103 }
Mike Fiore 3:08a693917d8c 104
Mike Fiore 3:08a693917d8c 105 /** This method returns the size of the storage space currently allocated for
Mike Fiore 3:08a693917d8c 106 * the buffer. This value is equivalent to the one passed into the constructor.
Mike Fiore 3:08a693917d8c 107 * This value is equal or greater than the size() of the buffer.
Mike Fiore 3:08a693917d8c 108 *
Mike Fiore 3:08a693917d8c 109 * @returns the allocated size of the buffer in bytes.
Mike Fiore 3:08a693917d8c 110 */
Mike Fiore 3:08a693917d8c 111 int capacity();
Mike Fiore 3:08a693917d8c 112
Mike Fiore 3:08a693917d8c 113 /** This method returns the amount of space left for writing.
Mike Fiore 3:08a693917d8c 114 *
Mike Fiore 3:08a693917d8c 115 * @returns numbers of unused bytes in buffer.
Mike Fiore 3:08a693917d8c 116 */
Mike Fiore 3:08a693917d8c 117 int remaining();
Mike Fiore 3:08a693917d8c 118
Mike Fiore 3:08a693917d8c 119 /** This method returns the number of bytes available for reading.
Mike Fiore 3:08a693917d8c 120 *
Mike Fiore 3:08a693917d8c 121 * @returns number of bytes currently in buffer.
Mike Fiore 3:08a693917d8c 122 */
Mike Fiore 3:08a693917d8c 123 int size();
Mike Fiore 3:08a693917d8c 124
Mike Fiore 3:08a693917d8c 125 /** This method returns whether the buffer is full.
Mike Fiore 3:08a693917d8c 126 *
Mike Fiore 3:08a693917d8c 127 * @returns true if full, otherwise false.
Mike Fiore 3:08a693917d8c 128 */
Mike Fiore 3:08a693917d8c 129 bool isFull();
Mike Fiore 3:08a693917d8c 130
Mike Fiore 3:08a693917d8c 131 /** This method returns whether the buffer is empty.
Mike Fiore 3:08a693917d8c 132 *
Mike Fiore 3:08a693917d8c 133 * @returns true if empty, otherwise false.
Mike Fiore 3:08a693917d8c 134 */
Mike Fiore 3:08a693917d8c 135 bool isEmpty();
Mike Fiore 3:08a693917d8c 136
Mike Fiore 3:08a693917d8c 137 /** This method clears the buffer. This is done through
Mike Fiore 3:08a693917d8c 138 * setting the internal read and write indexes to the same
Mike Fiore 3:08a693917d8c 139 * value and is therefore not an expensive operation.
Mike Fiore 3:08a693917d8c 140 */
Mike Fiore 3:08a693917d8c 141 void clear();
Mike Fiore 3:08a693917d8c 142
Mike Fiore 3:08a693917d8c 143
Mike Fiore 3:08a693917d8c 144 private:
Mike Fiore 3:08a693917d8c 145 int bufferSize; // total size of the buffer
Mike Fiore 3:08a693917d8c 146 char* buffer; // internal byte buffer as a character buffer
Mike Fiore 3:08a693917d8c 147 int readIndex; // read index for circular buffer
Mike Fiore 3:08a693917d8c 148 int writeIndex; // write index for circular buffer
Mike Fiore 3:08a693917d8c 149 int bytes; // available data
Mike Fiore 3:08a693917d8c 150 FunctionPointer notify; // function pointer used for the internal callback notification
Mike Fiore 3:08a693917d8c 151 int _threshold; // threshold for the notification
Mike Fiore 3:08a693917d8c 152 RelationalOperator _op; // operator that determines the direction of the threshold
Mike Fiore 3:08a693917d8c 153 void checkThreshold(); // private function that checks thresholds and processes notifications
Mike Fiore 3:08a693917d8c 154 };
Mike Fiore 3:08a693917d8c 155
Mike Fiore 3:08a693917d8c 156 }
Mike Fiore 3:08a693917d8c 157
Mike Fiore 3:08a693917d8c 158 #endif /* MTSCIRCULARBUFFER_H */