FATFileSystem.cpp

00001 /* mbed Microcontroller Library - FATFileSystem
00002  * Copyright (c) 2008, sford
00003  */
00004 
00005 #include "FATFileSystem.h"
00006 
00007 #include "mbed.h"
00008 
00009 #include "FileSystemLike.h"
00010 #include "FATFileHandle.h"
00011 #include "FATDirHandle.h"
00012 #include "ff.h"
00013 //#include "Debug.h"
00014 #include <stdio.h>
00015 #include <stdlib.h>
00016 
00017 DWORD get_fattime (void) {
00018     DWORD retval = 0;
00019     time_t seconds = time(NULL); // RTC time.
00020     if(seconds <=  0)
00021         seconds = 999;
00022     struct tm *t = localtime(&seconds);
00023     retval = 0;
00024     retval |= (t->tm_year - 80) << 25;
00025     retval |= (t->tm_mon + 1) << 21;
00026     retval |= (t->tm_mday) << 16;
00027     retval |= (t->tm_hour) << 11;
00028     retval |= (t->tm_min) << 5;
00029     retval |= (t->tm_sec) << 0;
00030     return retval;
00031 }
00032 
00033 namespace mbed {
00034 
00035 #if FFSDEBUG_ENABLED
00036 static const char *FR_ERRORS[] = {
00037     "FR_OK = 0", 
00038     "FR_NOT_READY",          
00039     "FR_NO_FILE",              
00040     "FR_NO_PATH",             
00041     "FR_INVALID_NAME",     
00042     "FR_INVALID_DRIVE",      
00043     "FR_DENIED",              
00044     "FR_EXIST",              
00045     "FR_RW_ERROR",          
00046     "FR_WRITE_PROTECTED", 
00047     "FR_NOT_ENABLED",    
00048     "FR_NO_FILESYSTEM",    
00049     "FR_INVALID_OBJECT",    
00050     "FR_MKFS_ABORTED"    
00051 };
00052 #endif
00053 
00054 FATFileSystem *FATFileSystem::_ffs[_DRIVES] = {0};
00055 
00056 FATFileSystem::FATFileSystem(const char* n) : FileSystemLike(n) {
00057     FFSDEBUG("FATFileSystem(%s)\n", n);
00058     for(int i=0; i<_DRIVES; i++) {
00059         if(_ffs[i] == 0) {
00060             _ffs[i] = this;
00061             _fsid = i;
00062             FFSDEBUG("Mounting [%s] on ffs drive [%d]\n", _name, _fsid);
00063             f_mount(i, &_fs);
00064             return;
00065         }
00066     }
00067     error("Couldn't create %s in FATFileSystem::FATFileSystem\n",n);
00068 }
00069     
00070 FATFileSystem::~FATFileSystem() {
00071     for(int i=0; i<_DRIVES; i++) {
00072         if(_ffs[i] == this) {
00073             _ffs[i] = 0;
00074             f_mount(i, NULL);
00075         }
00076     }
00077 }
00078     
00079 FileHandle *FATFileSystem::open(const char* name, int flags) {
00080     FFSDEBUG("open(%s) on filesystem [%s], drv [%d]\n", name, _name, _fsid);
00081     char n[64];
00082     sprintf(n, "%d:/%s", _fsid, name);
00083 
00084     /* POSIX flags -> FatFS open mode */
00085     BYTE openmode;
00086     if(flags & O_RDWR) {
00087         openmode = FA_READ|FA_WRITE;
00088     } else if(flags & O_WRONLY) {
00089         openmode = FA_WRITE;
00090     } else {
00091         openmode = FA_READ;
00092     }
00093     if(flags & O_CREAT) {
00094         if(flags & O_TRUNC) {
00095             openmode |= FA_CREATE_ALWAYS;
00096         } else {
00097             openmode |= FA_OPEN_ALWAYS;
00098         }
00099     }
00100 
00101     FIL_t fh;
00102     FRESULT res = f_open(&fh, n, openmode);
00103     if(res) { 
00104         FFSDEBUG("f_open('w') failed (%d, %s)\n", res, FR_ERRORS[res]);
00105         return NULL;
00106     }
00107     if(flags & O_APPEND) {
00108         f_lseek(&fh, fh.fsize);
00109     }
00110     return new FATFileHandle(fh);
00111 }
00112     
00113 int FATFileSystem::remove(const char *filename) {
00114     FRESULT res = f_unlink(filename);
00115     if(res) { 
00116         FFSDEBUG("f_unlink() failed (%d, %s)\n", res, FR_ERRORS[res]);
00117         return -1;
00118     }
00119     return 0;
00120 }
00121 
00122 int FATFileSystem::format() {
00123     FFSDEBUG("format()\n");
00124     FRESULT res = f_mkfs(_fsid, 0, 512); // Logical drive number, Partitioning rule, Allocation unit size (bytes per cluster)
00125     if(res) {
00126         FFSDEBUG("f_mkfs() failed (%d, %s)\n", res, FR_ERRORS[res]);
00127         return -1;
00128     }
00129     return 0;
00130 }
00131 
00132 DirHandle *FATFileSystem::opendir(const char *name) {
00133     DIR_t dir;
00134     FRESULT res = f_opendir(&dir, name);
00135     if(res != 0) {
00136         return NULL;
00137     }
00138     return new FATDirHandle(dir);
00139 }
00140 
00141 int FATFileSystem::mkdir(const char *name, mode_t mode) {
00142     FRESULT res = f_mkdir(name);
00143     return res == 0 ? 0 : -1;
00144 }
00145 
00146 } // namespace mbed