Tom Bloor / FatFileSystem

Some library needed for things? Licence unknown

Dependents:   LEDSign_SimpleSD

MemFileSystem.h@0:e4324838bc6f, 2012-07-29 (annotated)

Committer:
TBSliver
Date:
Sun Jul 29 10:07:38 2012 +0000
Revision:
0:e4324838bc6f
[mbed] converted /LEDSign_SimpleSD/FatFileSystem

Who changed what in which revision?

UserRevisionLine numberNew contents of line
TBSliver 0:e4324838bc6f 1 /* mbed Microcontroller Library - MemFileSystem
TBSliver 0:e4324838bc6f 2 * Copyright (c) 2008, sford
TBSliver 0:e4324838bc6f 3 */
TBSliver 0:e4324838bc6f 4
TBSliver 0:e4324838bc6f 5
TBSliver 0:e4324838bc6f 6 #ifndef MBED_MEMFILESYSTEM_H
TBSliver 0:e4324838bc6f 7 #define MBED_MEMFILESYSTEM_H
TBSliver 0:e4324838bc6f 8
TBSliver 0:e4324838bc6f 9 #include "FATFileSystem.h"
TBSliver 0:e4324838bc6f 10
TBSliver 0:e4324838bc6f 11 namespace mbed {
TBSliver 0:e4324838bc6f 12
TBSliver 0:e4324838bc6f 13 class MemFileSystem : public FATFileSystem {
TBSliver 0:e4324838bc6f 14 public:
TBSliver 0:e4324838bc6f 15
TBSliver 0:e4324838bc6f 16 // 2000 sectors, each 512 bytes (malloced as required)
TBSliver 0:e4324838bc6f 17 char *sectors[2000];
TBSliver 0:e4324838bc6f 18
TBSliver 0:e4324838bc6f 19 MemFileSystem(const char* name) : FATFileSystem(name) {
TBSliver 0:e4324838bc6f 20 memset(sectors, 0, sizeof(sectors));
TBSliver 0:e4324838bc6f 21 }
TBSliver 0:e4324838bc6f 22
TBSliver 0:e4324838bc6f 23 virtual ~MemFileSystem() {
TBSliver 0:e4324838bc6f 24 for(int i = 0; i < 2000; i++) {
TBSliver 0:e4324838bc6f 25 if(sectors[i]) {
TBSliver 0:e4324838bc6f 26 free(sectors[i]);
TBSliver 0:e4324838bc6f 27 }
TBSliver 0:e4324838bc6f 28 }
TBSliver 0:e4324838bc6f 29 }
TBSliver 0:e4324838bc6f 30
TBSliver 0:e4324838bc6f 31 // read a sector in to the buffer, return 0 if ok
TBSliver 0:e4324838bc6f 32 virtual int disk_read(char *buffer, int sector) {
TBSliver 0:e4324838bc6f 33 if(sectors[sector] == 0) {
TBSliver 0:e4324838bc6f 34 // nothing allocated means sector is empty
TBSliver 0:e4324838bc6f 35 memset(buffer, 0, 512);
TBSliver 0:e4324838bc6f 36 } else {
TBSliver 0:e4324838bc6f 37 memcpy(buffer, sectors[sector], 512);
TBSliver 0:e4324838bc6f 38 }
TBSliver 0:e4324838bc6f 39 return 0;
TBSliver 0:e4324838bc6f 40 }
TBSliver 0:e4324838bc6f 41
TBSliver 0:e4324838bc6f 42 // write a sector from the buffer, return 0 if ok
TBSliver 0:e4324838bc6f 43 virtual int disk_write(const char *buffer, int sector) {
TBSliver 0:e4324838bc6f 44 // if buffer is zero deallocate sector
TBSliver 0:e4324838bc6f 45 char zero[512];
TBSliver 0:e4324838bc6f 46 memset(zero, 0, 512);
TBSliver 0:e4324838bc6f 47 if(memcmp(zero, buffer, 512)==0) {
TBSliver 0:e4324838bc6f 48 if(sectors[sector] != 0) {
TBSliver 0:e4324838bc6f 49 free(sectors[sector]);
TBSliver 0:e4324838bc6f 50 sectors[sector] = 0;
TBSliver 0:e4324838bc6f 51 }
TBSliver 0:e4324838bc6f 52 return 0;
TBSliver 0:e4324838bc6f 53 }
TBSliver 0:e4324838bc6f 54 // else allocate a sector if needed, and write
TBSliver 0:e4324838bc6f 55 if(sectors[sector] == 0) {
TBSliver 0:e4324838bc6f 56 char *sec = (char*)malloc(512);
TBSliver 0:e4324838bc6f 57 if(sec==0) {
TBSliver 0:e4324838bc6f 58 return 1; // out of memory
TBSliver 0:e4324838bc6f 59 }
TBSliver 0:e4324838bc6f 60 sectors[sector] = sec;
TBSliver 0:e4324838bc6f 61 }
TBSliver 0:e4324838bc6f 62 memcpy(sectors[sector], buffer, 512);
TBSliver 0:e4324838bc6f 63 return 0;
TBSliver 0:e4324838bc6f 64 }
TBSliver 0:e4324838bc6f 65
TBSliver 0:e4324838bc6f 66 // return the number of sectors
TBSliver 0:e4324838bc6f 67 virtual int disk_sectors() {
TBSliver 0:e4324838bc6f 68 return sizeof(sectors)/sizeof(sectors[0]);
TBSliver 0:e4324838bc6f 69 }
TBSliver 0:e4324838bc6f 70
TBSliver 0:e4324838bc6f 71 };
TBSliver 0:e4324838bc6f 72
TBSliver 0:e4324838bc6f 73 }
TBSliver 0:e4324838bc6f 74
TBSliver 0:e4324838bc6f 75 #endif