Jon Freeman / circular_buffer

circular_buffer.cpp@3:7ef4c240d5e3, 2012-01-31 (annotated)

Committer:
JonFreeman
Date:
Tue Jan 31 09:56:38 2012 +0000
Revision:
3:7ef4c240d5e3
Parent:
0:2c2b17c7b7a8 
Rev3a, still learning how to document nicely

Who changed what in which revision?

UserRevisionLine numberNew contents of line
JonFreeman 0:2c2b17c7b7a8 1 #include "circular_buffer.h"
JonFreeman 0:2c2b17c7b7a8 2 #include "mbed.h"
JonFreeman 0:2c2b17c7b7a8 3
JonFreeman 0:2c2b17c7b7a8 4 using namespace std;
JonFreeman 0:2c2b17c7b7a8 5
JonFreeman 0:2c2b17c7b7a8 6 bool circular_buffer_f::seek (int distance_back) { // Assumes at least that much has been written to buff beforehand
JonFreeman 0:2c2b17c7b7a8 7 if(!seek_enable) return false;
JonFreeman 0:2c2b17c7b7a8 8 if(buffsize <= distance_back) return false;
JonFreeman 0:2c2b17c7b7a8 9 Offbuff = Onbuff - distance_back; // Setup to enable read of most recent 'distance_back' samples
JonFreeman 0:2c2b17c7b7a8 10 if(Offbuff < buffbase) Offbuff += buffsize;
JonFreeman 0:2c2b17c7b7a8 11 emptyf = false;
JonFreeman 0:2c2b17c7b7a8 12 return true;
JonFreeman 0:2c2b17c7b7a8 13 }
JonFreeman 0:2c2b17c7b7a8 14 void circular_buffer_f::init (int size, float *buffstart, int flags) { // Size and address of buffer to work with
JonFreeman 0:2c2b17c7b7a8 15 buffsize = size;
JonFreeman 0:2c2b17c7b7a8 16 Onbuff = Offbuff = buffend = buffbase = buffstart;
JonFreeman 0:2c2b17c7b7a8 17 buffend += (size - 1);
JonFreeman 0:2c2b17c7b7a8 18 emptyf = true; fullf = false;
JonFreeman 0:2c2b17c7b7a8 19 if (flags & OVERWRITE_ENABLE) overwrite_enable = true;
JonFreeman 0:2c2b17c7b7a8 20 else overwrite_enable = false;
JonFreeman 0:2c2b17c7b7a8 21 if (flags & SEEK_ENABLE) seek_enable = true;
JonFreeman 0:2c2b17c7b7a8 22 else seek_enable = false;
JonFreeman 0:2c2b17c7b7a8 23 }
JonFreeman 0:2c2b17c7b7a8 24 bool circular_buffer_f::read (float *rd) {
JonFreeman 0:2c2b17c7b7a8 25 if(!readable()) return false;
JonFreeman 0:2c2b17c7b7a8 26 *rd = *Offbuff++;
JonFreeman 0:2c2b17c7b7a8 27 if(Offbuff > buffend) Offbuff = buffbase;
JonFreeman 0:2c2b17c7b7a8 28 if(Onbuff == Offbuff) emptyf = true;
JonFreeman 0:2c2b17c7b7a8 29 fullf = false;
JonFreeman 0:2c2b17c7b7a8 30 return true;
JonFreeman 0:2c2b17c7b7a8 31 }
JonFreeman 0:2c2b17c7b7a8 32 bool circular_buffer_f::write (float a) { // Put value into circular buffer
JonFreeman 0:2c2b17c7b7a8 33 if (overwrite_enable) {
JonFreeman 0:2c2b17c7b7a8 34 *Onbuff++ = a; // post increment pointer
JonFreeman 0:2c2b17c7b7a8 35 if(Onbuff > buffend) Onbuff = buffbase;
JonFreeman 0:2c2b17c7b7a8 36 fullf = false;
JonFreeman 0:2c2b17c7b7a8 37 }
JonFreeman 0:2c2b17c7b7a8 38 else {
JonFreeman 0:2c2b17c7b7a8 39 if(fullf) return false; // Fail if buffer already full
JonFreeman 0:2c2b17c7b7a8 40 *Onbuff++ = a; // post increment pointer
JonFreeman 0:2c2b17c7b7a8 41 if(Onbuff > buffend) Onbuff = buffbase;
JonFreeman 0:2c2b17c7b7a8 42 if(Onbuff == Offbuff) fullf = true;
JonFreeman 0:2c2b17c7b7a8 43 }
JonFreeman 0:2c2b17c7b7a8 44 emptyf = false;
JonFreeman 0:2c2b17c7b7a8 45 return true;
JonFreeman 0:2c2b17c7b7a8 46 }
JonFreeman 0:2c2b17c7b7a8 47 bool circular_buffer_f::get_samps (float *dest, int len) {
JonFreeman 0:2c2b17c7b7a8 48 for (int i = 0; i < len; i++) {
JonFreeman 0:2c2b17c7b7a8 49 if (!read(dest++))
JonFreeman 0:2c2b17c7b7a8 50 return false;
JonFreeman 0:2c2b17c7b7a8 51 }
JonFreeman 0:2c2b17c7b7a8 52 return true;
JonFreeman 0:2c2b17c7b7a8 53 }
JonFreeman 0:2c2b17c7b7a8 54
JonFreeman 0:2c2b17c7b7a8 55 //////////////////////////
JonFreeman 0:2c2b17c7b7a8 56
JonFreeman 0:2c2b17c7b7a8 57 bool circular_buffer_c::seek (int distance_back) { // Assumes at least that much has been written to buff beforehand
JonFreeman 0:2c2b17c7b7a8 58 if(!seek_enable) return false;
JonFreeman 0:2c2b17c7b7a8 59 if(buffsize <= distance_back) return false;
JonFreeman 0:2c2b17c7b7a8 60 Offbuff = Onbuff - distance_back; // Setup to enable read of most recent 'distance_back' samples
JonFreeman 0:2c2b17c7b7a8 61 if(Offbuff < buffbase) Offbuff += buffsize;
JonFreeman 0:2c2b17c7b7a8 62 emptyf = false;
JonFreeman 0:2c2b17c7b7a8 63 return true;
JonFreeman 0:2c2b17c7b7a8 64 }
JonFreeman 0:2c2b17c7b7a8 65 void circular_buffer_c::init (int size, char *buffstart, int flags) { // Size and address of buffer to work with
JonFreeman 0:2c2b17c7b7a8 66 buffsize = size;
JonFreeman 0:2c2b17c7b7a8 67 Onbuff = Offbuff = buffend = buffbase = buffstart;
JonFreeman 0:2c2b17c7b7a8 68 buffend += (size - 1);
JonFreeman 0:2c2b17c7b7a8 69 emptyf = true; fullf = false;
JonFreeman 0:2c2b17c7b7a8 70 if (flags & OVERWRITE_ENABLE) overwrite_enable = true;
JonFreeman 0:2c2b17c7b7a8 71 else overwrite_enable = false;
JonFreeman 0:2c2b17c7b7a8 72 if (flags & SEEK_ENABLE) seek_enable = true;
JonFreeman 0:2c2b17c7b7a8 73 else seek_enable = false;
JonFreeman 0:2c2b17c7b7a8 74 }
JonFreeman 0:2c2b17c7b7a8 75 bool circular_buffer_c::read (char *rd) {
JonFreeman 0:2c2b17c7b7a8 76 if(!readable()) return false;
JonFreeman 0:2c2b17c7b7a8 77 *rd = *Offbuff++;
JonFreeman 0:2c2b17c7b7a8 78 if(Offbuff > buffend) Offbuff = buffbase;
JonFreeman 0:2c2b17c7b7a8 79 if(Onbuff == Offbuff) emptyf = true;
JonFreeman 0:2c2b17c7b7a8 80 fullf = false;
JonFreeman 0:2c2b17c7b7a8 81 return true;
JonFreeman 0:2c2b17c7b7a8 82 }
JonFreeman 0:2c2b17c7b7a8 83 bool circular_buffer_c::write (char a) { // Put value into circular buffer
JonFreeman 0:2c2b17c7b7a8 84 if (overwrite_enable) {
JonFreeman 0:2c2b17c7b7a8 85 *Onbuff++ = a; // post increment pointer
JonFreeman 0:2c2b17c7b7a8 86 if(Onbuff > buffend) Onbuff = buffbase;
JonFreeman 0:2c2b17c7b7a8 87 fullf = false;
JonFreeman 0:2c2b17c7b7a8 88 }
JonFreeman 0:2c2b17c7b7a8 89 else {
JonFreeman 0:2c2b17c7b7a8 90 if(fullf) return false; // Fail if buffer already full
JonFreeman 0:2c2b17c7b7a8 91 *Onbuff++ = a; // post increment pointer
JonFreeman 0:2c2b17c7b7a8 92 if(Onbuff > buffend) Onbuff = buffbase;
JonFreeman 0:2c2b17c7b7a8 93 if(Onbuff == Offbuff) fullf = true;
JonFreeman 0:2c2b17c7b7a8 94 }
JonFreeman 0:2c2b17c7b7a8 95 emptyf = false;
JonFreeman 0:2c2b17c7b7a8 96 return true;
JonFreeman 0:2c2b17c7b7a8 97 }
JonFreeman 0:2c2b17c7b7a8 98 bool circular_buffer_c::get_samps (char *dest, int len) {
JonFreeman 0:2c2b17c7b7a8 99 for (int i = 0; i < len; i++) {
JonFreeman 0:2c2b17c7b7a8 100 if (!read(dest++))
JonFreeman 0:2c2b17c7b7a8 101 return false;
JonFreeman 0:2c2b17c7b7a8 102 }
JonFreeman 0:2c2b17c7b7a8 103 return true;
JonFreeman 0:2c2b17c7b7a8 104 }
JonFreeman 0:2c2b17c7b7a8 105