Volodymyr Shymanskyy / Blynk Featured

Blynk library for embedded hardware. Works with Arduino, ESP8266, Raspberry Pi, Intel Edison/Galileo, LinkIt ONE, Particle Core/Photon, Energia, ARM mbed, etc. http://www.blynk.cc/

Dependents:   Blynk_RBL_BLE_Nano Blynk_MicroBit Blynk_Serial Blynk_RBL_BLE_Nano

utility/BlynkFifo.h@0:58b20b438383, 2016-05-07 (annotated)

Committer:
vshymanskyy
Date:
Sat May 07 08:02:50 2016 +0000
Revision:
0:58b20b438383
Child:
19:bae78e167b11
First commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
vshymanskyy 0:58b20b438383 1 /**
vshymanskyy 0:58b20b438383 2 * @file BlynkFifo.h
vshymanskyy 0:58b20b438383 3 * @author Volodymyr Shymanskyy
vshymanskyy 0:58b20b438383 4 * @license This project is released under the MIT License (MIT)
vshymanskyy 0:58b20b438383 5 * @copyright Copyright (c) 2015 Volodymyr Shymanskyy
vshymanskyy 0:58b20b438383 6 * @date Feb 2015
vshymanskyy 0:58b20b438383 7 * @brief FIFO implementation
vshymanskyy 0:58b20b438383 8 *
vshymanskyy 0:58b20b438383 9 */
vshymanskyy 0:58b20b438383 10
vshymanskyy 0:58b20b438383 11 #ifndef BlynkFifo_h
vshymanskyy 0:58b20b438383 12 #define BlynkFifo_h
vshymanskyy 0:58b20b438383 13
vshymanskyy 0:58b20b438383 14 #include <utility/BlynkUtility.h>
vshymanskyy 0:58b20b438383 15
vshymanskyy 0:58b20b438383 16 template<typename T, unsigned SIZE>
vshymanskyy 0:58b20b438383 17 class BlynkFifo {
vshymanskyy 0:58b20b438383 18
vshymanskyy 0:58b20b438383 19 BlynkFifo(const BlynkFifo<T, SIZE> & rb);
vshymanskyy 0:58b20b438383 20
vshymanskyy 0:58b20b438383 21 public:
vshymanskyy 0:58b20b438383 22
vshymanskyy 0:58b20b438383 23 BlynkFifo() : fst(0), lst(0), flag(0) {}
vshymanskyy 0:58b20b438383 24 ~BlynkFifo() {}
vshymanskyy 0:58b20b438383 25
vshymanskyy 0:58b20b438383 26 void clear() {
vshymanskyy 0:58b20b438383 27 fst = 0;
vshymanskyy 0:58b20b438383 28 lst = 0;
vshymanskyy 0:58b20b438383 29 flag = 0;
vshymanskyy 0:58b20b438383 30 }
vshymanskyy 0:58b20b438383 31
vshymanskyy 0:58b20b438383 32 size_t write(const T* data, size_t n)
vshymanskyy 0:58b20b438383 33 {
vshymanskyy 0:58b20b438383 34 if ((n = BlynkMin(n, getFree()))) {
vshymanskyy 0:58b20b438383 35 const size_t ch1 = BlynkMin(n, SIZE - lst);
vshymanskyy 0:58b20b438383 36 memcpy(buffer + lst, data, ch1 * sizeof(T));
vshymanskyy 0:58b20b438383 37 lst = (lst + ch1) % SIZE;
vshymanskyy 0:58b20b438383 38
vshymanskyy 0:58b20b438383 39 if (ch1 < n) {
vshymanskyy 0:58b20b438383 40 const size_t ch2 = n - ch1;
vshymanskyy 0:58b20b438383 41 memcpy(buffer + lst, data + ch1, ch2 * sizeof(T));
vshymanskyy 0:58b20b438383 42 lst = (lst + ch2) % SIZE;
vshymanskyy 0:58b20b438383 43 }
vshymanskyy 0:58b20b438383 44
vshymanskyy 0:58b20b438383 45 if (fst == lst) {
vshymanskyy 0:58b20b438383 46 flag = 1;
vshymanskyy 0:58b20b438383 47 }
vshymanskyy 0:58b20b438383 48 }
vshymanskyy 0:58b20b438383 49 return n;
vshymanskyy 0:58b20b438383 50 }
vshymanskyy 0:58b20b438383 51
vshymanskyy 0:58b20b438383 52 size_t read(T* dest, size_t n)
vshymanskyy 0:58b20b438383 53 {
vshymanskyy 0:58b20b438383 54 if ((n = BlynkMin(n, getOccupied()))) {
vshymanskyy 0:58b20b438383 55 flag = 0;
vshymanskyy 0:58b20b438383 56
vshymanskyy 0:58b20b438383 57 const size_t ch1 = BlynkMin(n, SIZE - fst);
vshymanskyy 0:58b20b438383 58 memcpy(dest, buffer + fst, ch1 * sizeof(T));
vshymanskyy 0:58b20b438383 59 fst = (fst + ch1) % SIZE;
vshymanskyy 0:58b20b438383 60
vshymanskyy 0:58b20b438383 61 if (ch1 < n) {
vshymanskyy 0:58b20b438383 62 const size_t ch2 = n - ch1;
vshymanskyy 0:58b20b438383 63 memcpy(dest + ch1, buffer + fst, ch2 * sizeof(T));
vshymanskyy 0:58b20b438383 64 fst = (fst + ch2) % SIZE;
vshymanskyy 0:58b20b438383 65 }
vshymanskyy 0:58b20b438383 66 }
vshymanskyy 0:58b20b438383 67 return n;
vshymanskyy 0:58b20b438383 68 }
vshymanskyy 0:58b20b438383 69
vshymanskyy 0:58b20b438383 70 bool push(const T& data) {
vshymanskyy 0:58b20b438383 71 return write(&data, 1) == 1;
vshymanskyy 0:58b20b438383 72 }
vshymanskyy 0:58b20b438383 73
vshymanskyy 0:58b20b438383 74 size_t getOccupied() const {
vshymanskyy 0:58b20b438383 75 if (lst == fst) {
vshymanskyy 0:58b20b438383 76 return flag ? SIZE : 0;
vshymanskyy 0:58b20b438383 77 } else if (lst > fst) {
vshymanskyy 0:58b20b438383 78 return lst - fst;
vshymanskyy 0:58b20b438383 79 } else {
vshymanskyy 0:58b20b438383 80 return SIZE + lst - fst;
vshymanskyy 0:58b20b438383 81 }
vshymanskyy 0:58b20b438383 82 }
vshymanskyy 0:58b20b438383 83
vshymanskyy 0:58b20b438383 84 size_t getFree() const {
vshymanskyy 0:58b20b438383 85 return SIZE - getOccupied();
vshymanskyy 0:58b20b438383 86 }
vshymanskyy 0:58b20b438383 87
vshymanskyy 0:58b20b438383 88 private:
vshymanskyy 0:58b20b438383 89 T buffer[SIZE];
vshymanskyy 0:58b20b438383 90 size_t fst;
vshymanskyy 0:58b20b438383 91 size_t lst;
vshymanskyy 0:58b20b438383 92 uint8_t flag;
vshymanskyy 0:58b20b438383 93 };
vshymanskyy 0:58b20b438383 94
vshymanskyy 0:58b20b438383 95 #endif