ahmed ahmed / Ahmed_Embarq_Prog

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Dependencies:   C12832 LM75B mbed

_Log/FileSystem/FatFileSystem/MemFileSystem.h@0:05a20e3e3179, 2015-04-21 (annotated)

Committer:
pfe
Date:
Tue Apr 21 10:16:20 2015 +0000
Revision:
0:05a20e3e3179
dd

Who changed what in which revision?

UserRevisionLine numberNew contents of line
pfe 0:05a20e3e3179 1 /* mbed Microcontroller Library - MemFileSystem
pfe 0:05a20e3e3179 2 * Copyright (c) 2008, sford
pfe 0:05a20e3e3179 3 */
pfe 0:05a20e3e3179 4
pfe 0:05a20e3e3179 5
pfe 0:05a20e3e3179 6 #ifndef MBED_MEMFILESYSTEM_H
pfe 0:05a20e3e3179 7 #define MBED_MEMFILESYSTEM_H
pfe 0:05a20e3e3179 8
pfe 0:05a20e3e3179 9 #include "FATFileSystem.h"
pfe 0:05a20e3e3179 10
pfe 0:05a20e3e3179 11 namespace mbed {
pfe 0:05a20e3e3179 12
pfe 0:05a20e3e3179 13 class MemFileSystem : public FATFileSystem {
pfe 0:05a20e3e3179 14 public:
pfe 0:05a20e3e3179 15
pfe 0:05a20e3e3179 16 // 2000 sectors, each 512 bytes (malloced as required)
pfe 0:05a20e3e3179 17 char *sectors[2000];
pfe 0:05a20e3e3179 18
pfe 0:05a20e3e3179 19 MemFileSystem(const char* name) : FATFileSystem(name) {
pfe 0:05a20e3e3179 20 memset(sectors, 0, sizeof(sectors));
pfe 0:05a20e3e3179 21 }
pfe 0:05a20e3e3179 22
pfe 0:05a20e3e3179 23 virtual ~MemFileSystem() {
pfe 0:05a20e3e3179 24 for(int i = 0; i < 2000; i++) {
pfe 0:05a20e3e3179 25 if(sectors[i]) {
pfe 0:05a20e3e3179 26 free(sectors[i]);
pfe 0:05a20e3e3179 27 }
pfe 0:05a20e3e3179 28 }
pfe 0:05a20e3e3179 29 }
pfe 0:05a20e3e3179 30
pfe 0:05a20e3e3179 31 // read a sector in to the buffer, return 0 if ok
pfe 0:05a20e3e3179 32 virtual int disk_read(char *buffer, int sector) {
pfe 0:05a20e3e3179 33 if(sectors[sector] == 0) {
pfe 0:05a20e3e3179 34 // nothing allocated means sector is empty
pfe 0:05a20e3e3179 35 memset(buffer, 0, 512);
pfe 0:05a20e3e3179 36 } else {
pfe 0:05a20e3e3179 37 memcpy(buffer, sectors[sector], 512);
pfe 0:05a20e3e3179 38 }
pfe 0:05a20e3e3179 39 return 0;
pfe 0:05a20e3e3179 40 }
pfe 0:05a20e3e3179 41
pfe 0:05a20e3e3179 42 // write a sector from the buffer, return 0 if ok
pfe 0:05a20e3e3179 43 virtual int disk_write(const char *buffer, int sector) {
pfe 0:05a20e3e3179 44 // if buffer is zero deallocate sector
pfe 0:05a20e3e3179 45 char zero[512];
pfe 0:05a20e3e3179 46 memset(zero, 0, 512);
pfe 0:05a20e3e3179 47 if(memcmp(zero, buffer, 512)==0) {
pfe 0:05a20e3e3179 48 if(sectors[sector] != 0) {
pfe 0:05a20e3e3179 49 free(sectors[sector]);
pfe 0:05a20e3e3179 50 sectors[sector] = 0;
pfe 0:05a20e3e3179 51 }
pfe 0:05a20e3e3179 52 return 0;
pfe 0:05a20e3e3179 53 }
pfe 0:05a20e3e3179 54 // else allocate a sector if needed, and write
pfe 0:05a20e3e3179 55 if(sectors[sector] == 0) {
pfe 0:05a20e3e3179 56 char *sec = (char*)malloc(512);
pfe 0:05a20e3e3179 57 if(sec==0) {
pfe 0:05a20e3e3179 58 return 1; // out of memory
pfe 0:05a20e3e3179 59 }
pfe 0:05a20e3e3179 60 sectors[sector] = sec;
pfe 0:05a20e3e3179 61 }
pfe 0:05a20e3e3179 62 memcpy(sectors[sector], buffer, 512);
pfe 0:05a20e3e3179 63 return 0;
pfe 0:05a20e3e3179 64 }
pfe 0:05a20e3e3179 65
pfe 0:05a20e3e3179 66 // return the number of sectors
pfe 0:05a20e3e3179 67 virtual int disk_sectors() {
pfe 0:05a20e3e3179 68 return sizeof(sectors)/sizeof(sectors[0]);
pfe 0:05a20e3e3179 69 }
pfe 0:05a20e3e3179 70
pfe 0:05a20e3e3179 71 };
pfe 0:05a20e3e3179 72
pfe 0:05a20e3e3179 73 }
pfe 0:05a20e3e3179 74
pfe 0:05a20e3e3179 75 #endif