Li Weiyi / Blynk

Work on LPC824. 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:   ESP8266BlynkWeatherStation TEST123

Fork of Blynk by Volodymyr Shymanskyy

utility/BlynkFifo2.h@2:1538810a5d87, 2016-06-16 (annotated)

Committer:
lixianyu
Date:
Thu Jun 16 08:06:28 2016 +0000
Revision:
2:1538810a5d87
Parent:
0:58b20b438383 
?9600?????ESP8266????????115200??ESP8266???????9600?????????????????Timer?????

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 <class T, unsigned N>
vshymanskyy 0:58b20b438383 17 class BlynkFifo
vshymanskyy 0:58b20b438383 18 {
vshymanskyy 0:58b20b438383 19 public:
vshymanskyy 0:58b20b438383 20 BlynkFifo()
vshymanskyy 0:58b20b438383 21 {
vshymanskyy 0:58b20b438383 22 clear();
vshymanskyy 0:58b20b438383 23 }
vshymanskyy 0:58b20b438383 24
vshymanskyy 0:58b20b438383 25 void clear()
vshymanskyy 0:58b20b438383 26 {
vshymanskyy 0:58b20b438383 27 _r = 0;
vshymanskyy 0:58b20b438383 28 _w = 0;
vshymanskyy 0:58b20b438383 29 }
vshymanskyy 0:58b20b438383 30
vshymanskyy 0:58b20b438383 31 ~BlynkFifo(void)
vshymanskyy 0:58b20b438383 32 {}
vshymanskyy 0:58b20b438383 33
vshymanskyy 0:58b20b438383 34 // writing thread/context API
vshymanskyy 0:58b20b438383 35 //-------------------------------------------------------------
vshymanskyy 0:58b20b438383 36
vshymanskyy 0:58b20b438383 37 bool writeable(void)
vshymanskyy 0:58b20b438383 38 {
vshymanskyy 0:58b20b438383 39 return free() > 0;
vshymanskyy 0:58b20b438383 40 }
vshymanskyy 0:58b20b438383 41
vshymanskyy 0:58b20b438383 42 int free(void)
vshymanskyy 0:58b20b438383 43 {
vshymanskyy 0:58b20b438383 44 int s = _r - _w;
vshymanskyy 0:58b20b438383 45 if (s <= 0)
vshymanskyy 0:58b20b438383 46 s += N;
vshymanskyy 0:58b20b438383 47 return s - 1;
vshymanskyy 0:58b20b438383 48 }
vshymanskyy 0:58b20b438383 49
vshymanskyy 0:58b20b438383 50 T put(const T& c)
vshymanskyy 0:58b20b438383 51 {
vshymanskyy 0:58b20b438383 52 int i = _w;
vshymanskyy 0:58b20b438383 53 int j = i;
vshymanskyy 0:58b20b438383 54 i = _inc(i);
vshymanskyy 0:58b20b438383 55 while (i == _r) // = !writeable()
vshymanskyy 0:58b20b438383 56 /* nothing / just wait */;
vshymanskyy 0:58b20b438383 57 _b[j] = c;
vshymanskyy 0:58b20b438383 58 _w = i;
vshymanskyy 0:58b20b438383 59 return c;
vshymanskyy 0:58b20b438383 60 }
vshymanskyy 0:58b20b438383 61
vshymanskyy 0:58b20b438383 62 int put(const T* p, int n, bool t = false)
vshymanskyy 0:58b20b438383 63 {
vshymanskyy 0:58b20b438383 64 int c = n;
vshymanskyy 0:58b20b438383 65 while (c)
vshymanskyy 0:58b20b438383 66 {
vshymanskyy 0:58b20b438383 67 int f;
vshymanskyy 0:58b20b438383 68 while ((f = free()) == 0) // wait for space
vshymanskyy 0:58b20b438383 69 {
vshymanskyy 0:58b20b438383 70 if (!t) return n - c; // no more space and not blocking
vshymanskyy 0:58b20b438383 71 /* nothing / just wait */;
vshymanskyy 0:58b20b438383 72 }
vshymanskyy 0:58b20b438383 73 // check free space
vshymanskyy 0:58b20b438383 74 if (c < f) f = c;
vshymanskyy 0:58b20b438383 75 int w = _w;
vshymanskyy 0:58b20b438383 76 int m = N - w;
vshymanskyy 0:58b20b438383 77 // check wrap
vshymanskyy 0:58b20b438383 78 if (f > m) f = m;
vshymanskyy 0:58b20b438383 79 memcpy(&_b[w], p, f);
vshymanskyy 0:58b20b438383 80 _w = _inc(w, f);
vshymanskyy 0:58b20b438383 81 c -= f;
vshymanskyy 0:58b20b438383 82 p += f;
vshymanskyy 0:58b20b438383 83 }
vshymanskyy 0:58b20b438383 84 return n - c;
vshymanskyy 0:58b20b438383 85 }
vshymanskyy 0:58b20b438383 86
vshymanskyy 0:58b20b438383 87 // reading thread/context API
vshymanskyy 0:58b20b438383 88 // --------------------------------------------------------
vshymanskyy 0:58b20b438383 89
vshymanskyy 0:58b20b438383 90 bool readable(void)
vshymanskyy 0:58b20b438383 91 {
vshymanskyy 0:58b20b438383 92 return (_r != _w);
vshymanskyy 0:58b20b438383 93 }
vshymanskyy 0:58b20b438383 94
vshymanskyy 0:58b20b438383 95 size_t size(void)
vshymanskyy 0:58b20b438383 96 {
vshymanskyy 0:58b20b438383 97 int s = _w - _r;
vshymanskyy 0:58b20b438383 98 if (s < 0)
vshymanskyy 0:58b20b438383 99 s += N;
vshymanskyy 0:58b20b438383 100 return s;
vshymanskyy 0:58b20b438383 101 }
vshymanskyy 0:58b20b438383 102
vshymanskyy 0:58b20b438383 103 T get(void)
vshymanskyy 0:58b20b438383 104 {
vshymanskyy 0:58b20b438383 105 int r = _r;
vshymanskyy 0:58b20b438383 106 while (r == _w) // = !readable()
vshymanskyy 0:58b20b438383 107 /* nothing / just wait */;
vshymanskyy 0:58b20b438383 108 T t = _b[r];
vshymanskyy 0:58b20b438383 109 _r = _inc(r);
vshymanskyy 0:58b20b438383 110 return t;
vshymanskyy 0:58b20b438383 111 }
vshymanskyy 0:58b20b438383 112
vshymanskyy 0:58b20b438383 113 int get(T* p, int n, bool t = false)
vshymanskyy 0:58b20b438383 114 {
vshymanskyy 0:58b20b438383 115 int c = n;
vshymanskyy 0:58b20b438383 116 while (c)
vshymanskyy 0:58b20b438383 117 {
vshymanskyy 0:58b20b438383 118 int f;
vshymanskyy 0:58b20b438383 119 for (;;) // wait for data
vshymanskyy 0:58b20b438383 120 {
vshymanskyy 0:58b20b438383 121 f = size();
vshymanskyy 0:58b20b438383 122 if (f) break; // free space
vshymanskyy 0:58b20b438383 123 if (!t) return n - c; // no space and not blocking
vshymanskyy 0:58b20b438383 124 /* nothing / just wait */;
vshymanskyy 0:58b20b438383 125 }
vshymanskyy 0:58b20b438383 126 // check available data
vshymanskyy 0:58b20b438383 127 if (c < f) f = c;
vshymanskyy 0:58b20b438383 128 int r = _r;
vshymanskyy 0:58b20b438383 129 int m = N - r;
vshymanskyy 0:58b20b438383 130 // check wrap
vshymanskyy 0:58b20b438383 131 if (f > m) f = m;
vshymanskyy 0:58b20b438383 132 memcpy(p, &_b[r], f);
vshymanskyy 0:58b20b438383 133 _r = _inc(r, f);
vshymanskyy 0:58b20b438383 134 c -= f;
vshymanskyy 0:58b20b438383 135 p += f;
vshymanskyy 0:58b20b438383 136 }
vshymanskyy 0:58b20b438383 137 return n - c;
vshymanskyy 0:58b20b438383 138 }
vshymanskyy 0:58b20b438383 139
vshymanskyy 0:58b20b438383 140 private:
vshymanskyy 0:58b20b438383 141 inline int _inc(int i, int n = 1)
vshymanskyy 0:58b20b438383 142 {
vshymanskyy 0:58b20b438383 143 return (i + n) % N;
vshymanskyy 0:58b20b438383 144 }
vshymanskyy 0:58b20b438383 145
vshymanskyy 0:58b20b438383 146 T _b[N];
vshymanskyy 0:58b20b438383 147 volatile int _w;
vshymanskyy 0:58b20b438383 148 volatile int _r;
vshymanskyy 0:58b20b438383 149 };
vshymanskyy 0:58b20b438383 150
vshymanskyy 0:58b20b438383 151 #endif