ELEC2645 (2019/20) / Mbed 2 deprecated ELEC2645_PROJECT_EL18KK

Kaif Kutchwala 201267448 ELEC2645 Project

Dependencies:   mbed

SDFileSystem/FATFileSystem/MemFileSystem.h@31:e1f80d181779, 2020-05-26 (annotated)

Committer:
KaifK
Date:
Tue May 26 15:50:46 2020 +0000
Revision:
31:e1f80d181779
Parent:
21:d5b1160f349f 
Final Submission. I have read and agreed with Statement of Academic Integrity.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
KaifK 21:d5b1160f349f 1 /* mbed Microcontroller Library - MemFileSystem
KaifK 21:d5b1160f349f 2 * Copyright (c) 2008, sford
KaifK 21:d5b1160f349f 3 */
KaifK 21:d5b1160f349f 4
KaifK 21:d5b1160f349f 5
KaifK 21:d5b1160f349f 6 #ifndef MBED_MEMFILESYSTEM_H
KaifK 21:d5b1160f349f 7 #define MBED_MEMFILESYSTEM_H
KaifK 21:d5b1160f349f 8
KaifK 21:d5b1160f349f 9 #include "FATFileSystem.h"
KaifK 21:d5b1160f349f 10
KaifK 21:d5b1160f349f 11 namespace mbed
KaifK 21:d5b1160f349f 12 {
KaifK 21:d5b1160f349f 13
KaifK 21:d5b1160f349f 14 class MemFileSystem : public FATFileSystem
KaifK 21:d5b1160f349f 15 {
KaifK 21:d5b1160f349f 16 public:
KaifK 21:d5b1160f349f 17
KaifK 21:d5b1160f349f 18 // 2000 sectors, each 512 bytes (malloced as required)
KaifK 21:d5b1160f349f 19 char *sectors[2000];
KaifK 21:d5b1160f349f 20
KaifK 21:d5b1160f349f 21 MemFileSystem(const char* name) : FATFileSystem(name) {
KaifK 21:d5b1160f349f 22 memset(sectors, 0, sizeof(sectors));
KaifK 21:d5b1160f349f 23 }
KaifK 21:d5b1160f349f 24
KaifK 21:d5b1160f349f 25 virtual ~MemFileSystem() {
KaifK 21:d5b1160f349f 26 for(int i = 0; i < 2000; i++) {
KaifK 21:d5b1160f349f 27 if(sectors[i]) {
KaifK 21:d5b1160f349f 28 free(sectors[i]);
KaifK 21:d5b1160f349f 29 }
KaifK 21:d5b1160f349f 30 }
KaifK 21:d5b1160f349f 31 }
KaifK 21:d5b1160f349f 32
KaifK 21:d5b1160f349f 33 // read a sector in to the buffer, return 0 if ok
KaifK 21:d5b1160f349f 34 virtual int disk_read(char *buffer, int sector) {
KaifK 21:d5b1160f349f 35 if(sectors[sector] == 0) {
KaifK 21:d5b1160f349f 36 // nothing allocated means sector is empty
KaifK 21:d5b1160f349f 37 memset(buffer, 0, 512);
KaifK 21:d5b1160f349f 38 } else {
KaifK 21:d5b1160f349f 39 memcpy(buffer, sectors[sector], 512);
KaifK 21:d5b1160f349f 40 }
KaifK 21:d5b1160f349f 41 return 0;
KaifK 21:d5b1160f349f 42 }
KaifK 21:d5b1160f349f 43
KaifK 21:d5b1160f349f 44 // write a sector from the buffer, return 0 if ok
KaifK 21:d5b1160f349f 45 virtual int disk_write(const char *buffer, int sector) {
KaifK 21:d5b1160f349f 46 // if buffer is zero deallocate sector
KaifK 21:d5b1160f349f 47 char zero[512];
KaifK 21:d5b1160f349f 48 memset(zero, 0, 512);
KaifK 21:d5b1160f349f 49 if(memcmp(zero, buffer, 512)==0) {
KaifK 21:d5b1160f349f 50 if(sectors[sector] != 0) {
KaifK 21:d5b1160f349f 51 free(sectors[sector]);
KaifK 21:d5b1160f349f 52 sectors[sector] = 0;
KaifK 21:d5b1160f349f 53 }
KaifK 21:d5b1160f349f 54 return 0;
KaifK 21:d5b1160f349f 55 }
KaifK 21:d5b1160f349f 56 // else allocate a sector if needed, and write
KaifK 21:d5b1160f349f 57 if(sectors[sector] == 0) {
KaifK 21:d5b1160f349f 58 char *sec = (char*)malloc(512);
KaifK 21:d5b1160f349f 59 if(sec==0) {
KaifK 21:d5b1160f349f 60 return 1; // out of memory
KaifK 21:d5b1160f349f 61 }
KaifK 21:d5b1160f349f 62 sectors[sector] = sec;
KaifK 21:d5b1160f349f 63 }
KaifK 21:d5b1160f349f 64 memcpy(sectors[sector], buffer, 512);
KaifK 21:d5b1160f349f 65 return 0;
KaifK 21:d5b1160f349f 66 }
KaifK 21:d5b1160f349f 67
KaifK 21:d5b1160f349f 68 // return the number of sectors
KaifK 21:d5b1160f349f 69 virtual int disk_sectors() {
KaifK 21:d5b1160f349f 70 return sizeof(sectors)/sizeof(sectors[0]);
KaifK 21:d5b1160f349f 71 }
KaifK 21:d5b1160f349f 72
KaifK 21:d5b1160f349f 73 };
KaifK 21:d5b1160f349f 74
KaifK 21:d5b1160f349f 75 }
KaifK 21:d5b1160f349f 76
KaifK 21:d5b1160f349f 77 #endif