Revised to support ability to have both SD and USB drives mounted.
Dependents: Multi-FileSystem Multi-FileSystem
Fork of FATFileSystem by
MemFileSystem.h@12:d816f503fc6f, 2017-07-29 (annotated)
- Committer:
- WiredHome
- Date:
- Sat Jul 29 12:39:03 2017 +0000
- Revision:
- 12:d816f503fc6f
- Parent:
- 11:2f7ad4af3ec1
Reduce the number of sectors definition
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
screamer | 3:e960e2b81a3c | 1 | /* mbed Microcontroller Library - MemFileSystem |
screamer | 3:e960e2b81a3c | 2 | * Copyright (c) 2008, sford |
screamer | 3:e960e2b81a3c | 3 | */ |
screamer | 3:e960e2b81a3c | 4 | |
screamer | 3:e960e2b81a3c | 5 | |
screamer | 3:e960e2b81a3c | 6 | #ifndef MBED_MEMFILESYSTEM_H |
screamer | 3:e960e2b81a3c | 7 | #define MBED_MEMFILESYSTEM_H |
screamer | 3:e960e2b81a3c | 8 | |
screamer | 3:e960e2b81a3c | 9 | #include "FATFileSystem.h" |
screamer | 3:e960e2b81a3c | 10 | |
WiredHome | 11:2f7ad4af3ec1 | 11 | // 4 Bytes / Sector, each 512 Bytes - malloc'd as required |
WiredHome | 11:2f7ad4af3ec1 | 12 | // Value was 2000 (8K) |
WiredHome | 12:d816f503fc6f | 13 | #define NUM_SECTORS 100 |
WiredHome | 11:2f7ad4af3ec1 | 14 | #define SECTOR_SIZE 512 |
WiredHome | 11:2f7ad4af3ec1 | 15 | |
WiredHome | 11:2f7ad4af3ec1 | 16 | // moved the zeroed RAM buffer to flash, |
WiredHome | 11:2f7ad4af3ec1 | 17 | // so it doesn't waste precious RAM |
WiredHome | 11:2f7ad4af3ec1 | 18 | static const char zero[SECTOR_SIZE] = {0}; |
WiredHome | 11:2f7ad4af3ec1 | 19 | |
screamer | 3:e960e2b81a3c | 20 | namespace mbed |
screamer | 3:e960e2b81a3c | 21 | { |
screamer | 3:e960e2b81a3c | 22 | class MemFileSystem : public FATFileSystem |
screamer | 3:e960e2b81a3c | 23 | { |
screamer | 3:e960e2b81a3c | 24 | public: |
WiredHome | 11:2f7ad4af3ec1 | 25 | // NUM_SECTORS sectors, each 512 bytes (malloced as required) |
WiredHome | 11:2f7ad4af3ec1 | 26 | char *sectors[NUM_SECTORS]; |
screamer | 3:e960e2b81a3c | 27 | |
screamer | 3:e960e2b81a3c | 28 | MemFileSystem(const char* name) : FATFileSystem(name) { |
screamer | 3:e960e2b81a3c | 29 | memset(sectors, 0, sizeof(sectors)); |
screamer | 3:e960e2b81a3c | 30 | } |
WiredHome | 11:2f7ad4af3ec1 | 31 | |
screamer | 3:e960e2b81a3c | 32 | virtual ~MemFileSystem() { |
WiredHome | 11:2f7ad4af3ec1 | 33 | for(int i = 0; i < NUM_SECTORS; i++) { |
screamer | 3:e960e2b81a3c | 34 | if(sectors[i]) { |
screamer | 3:e960e2b81a3c | 35 | free(sectors[i]); |
screamer | 3:e960e2b81a3c | 36 | } |
screamer | 3:e960e2b81a3c | 37 | } |
screamer | 3:e960e2b81a3c | 38 | } |
WiredHome | 11:2f7ad4af3ec1 | 39 | |
screamer | 3:e960e2b81a3c | 40 | // read a sector in to the buffer, return 0 if ok |
screamer | 3:e960e2b81a3c | 41 | virtual int disk_read(char *buffer, int sector) { |
screamer | 3:e960e2b81a3c | 42 | if(sectors[sector] == 0) { |
screamer | 3:e960e2b81a3c | 43 | // nothing allocated means sector is empty |
WiredHome | 11:2f7ad4af3ec1 | 44 | memset(buffer, 0, SECTOR_SIZE); |
screamer | 3:e960e2b81a3c | 45 | } else { |
WiredHome | 11:2f7ad4af3ec1 | 46 | memcpy(buffer, sectors[sector], SECTOR_SIZE); |
screamer | 3:e960e2b81a3c | 47 | } |
screamer | 3:e960e2b81a3c | 48 | return 0; |
screamer | 3:e960e2b81a3c | 49 | } |
WiredHome | 11:2f7ad4af3ec1 | 50 | |
screamer | 3:e960e2b81a3c | 51 | // write a sector from the buffer, return 0 if ok |
screamer | 3:e960e2b81a3c | 52 | virtual int disk_write(const char *buffer, int sector) { |
screamer | 3:e960e2b81a3c | 53 | // if buffer is zero deallocate sector |
WiredHome | 11:2f7ad4af3ec1 | 54 | //char zero[SECTOR_SIZE] = {0}; // DS this used to be a ram buffer |
WiredHome | 11:2f7ad4af3ec1 | 55 | //memset(zero, 0, SECTOR_SIZE); |
WiredHome | 11:2f7ad4af3ec1 | 56 | if(memcmp(zero, buffer, SECTOR_SIZE)==0) { |
screamer | 3:e960e2b81a3c | 57 | if(sectors[sector] != 0) { |
screamer | 3:e960e2b81a3c | 58 | free(sectors[sector]); |
screamer | 3:e960e2b81a3c | 59 | sectors[sector] = 0; |
screamer | 3:e960e2b81a3c | 60 | } |
screamer | 3:e960e2b81a3c | 61 | return 0; |
screamer | 3:e960e2b81a3c | 62 | } |
screamer | 3:e960e2b81a3c | 63 | // else allocate a sector if needed, and write |
screamer | 3:e960e2b81a3c | 64 | if(sectors[sector] == 0) { |
WiredHome | 11:2f7ad4af3ec1 | 65 | char *sec = (char*)malloc(SECTOR_SIZE); |
screamer | 3:e960e2b81a3c | 66 | if(sec==0) { |
screamer | 3:e960e2b81a3c | 67 | return 1; // out of memory |
screamer | 3:e960e2b81a3c | 68 | } |
screamer | 3:e960e2b81a3c | 69 | sectors[sector] = sec; |
screamer | 3:e960e2b81a3c | 70 | } |
WiredHome | 11:2f7ad4af3ec1 | 71 | memcpy(sectors[sector], buffer, SECTOR_SIZE); |
screamer | 3:e960e2b81a3c | 72 | return 0; |
screamer | 3:e960e2b81a3c | 73 | } |
WiredHome | 11:2f7ad4af3ec1 | 74 | |
screamer | 3:e960e2b81a3c | 75 | // return the number of sectors |
screamer | 3:e960e2b81a3c | 76 | virtual int disk_sectors() { |
screamer | 3:e960e2b81a3c | 77 | return sizeof(sectors)/sizeof(sectors[0]); |
screamer | 3:e960e2b81a3c | 78 | } |
screamer | 3:e960e2b81a3c | 79 | }; |
screamer | 3:e960e2b81a3c | 80 | } |
screamer | 3:e960e2b81a3c | 81 | |
screamer | 3:e960e2b81a3c | 82 | #endif |