help :(
Dependencies: FFT
FATFileSystem/MemFileSystem.h
- Committer:
- annieluo2
- Date:
- 2020-12-02
- Revision:
- 0:d6c9b09b4042
File content as of revision 0:d6c9b09b4042:
/* mbed Microcontroller Library - MemFileSystem * Copyright (c) 2008, sford */ #ifndef MBED_MEMFILESYSTEM_H #define MBED_MEMFILESYSTEM_H #include "FATFileSystem.h" namespace mbed { class MemFileSystem : public FATFileSystem { public: // 2000 sectors, each 512 bytes (malloced as required) char *sectors[2000]; MemFileSystem(const char* name) : FATFileSystem(name) { memset(sectors, 0, sizeof(sectors)); } virtual ~MemFileSystem() { for(int i = 0; i < 2000; i++) { if(sectors[i]) { free(sectors[i]); } } } // read a sector in to the buffer, return 0 if ok virtual int disk_read(char *buffer, int sector) { if(sectors[sector] == 0) { // nothing allocated means sector is empty memset(buffer, 0, 512); } else { memcpy(buffer, sectors[sector], 512); } return 0; } // write a sector from the buffer, return 0 if ok virtual int disk_write(const char *buffer, int sector) { // if buffer is zero deallocate sector char zero[512]; memset(zero, 0, 512); if(memcmp(zero, buffer, 512)==0) { if(sectors[sector] != 0) { free(sectors[sector]); sectors[sector] = 0; } return 0; } // else allocate a sector if needed, and write if(sectors[sector] == 0) { char *sec = (char*)malloc(512); if(sec==0) { return 1; // out of memory } sectors[sector] = sec; } memcpy(sectors[sector], buffer, 512); return 0; } // return the number of sectors virtual int disk_sectors() { return sizeof(sectors)/sizeof(sectors[0]); } }; } #endif