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     return 999;
00019 }
00020 
00021 namespace mbed {
00022 
00023 #if FFSDEBUG_ENABLED
00024 static const char *FR_ERRORS[] = {
00025     "FR_OK = 0",
00026     "FR_NOT_READY",
00027     "FR_NO_FILE",
00028     "FR_NO_PATH",
00029     "FR_INVALID_NAME",
00030     "FR_INVALID_DRIVE",
00031     "FR_DENIED",
00032     "FR_EXIST",
00033     "FR_RW_ERROR",
00034     "FR_WRITE_PROTECTED",
00035     "FR_NOT_ENABLED",
00036     "FR_NO_FILESYSTEM",
00037     "FR_INVALID_OBJECT",
00038     "FR_MKFS_ABORTED"
00039 };
00040 #endif
00041 
00042 FATFileSystem *FATFileSystem::_ffs[_DRIVES] = {0};
00043 
00044 FATFileSystem::FATFileSystem(const char* n) : FileSystemLike(n) {
00045     FFSDEBUG("FATFileSystem(%s)\n", n);
00046     for(int i=0; i<_DRIVES; i++) {
00047         if(_ffs[i] == 0) {
00048             _ffs[i] = this;
00049             _fsid = i;
00050             FFSDEBUG("Mounting [%s] on ffs drive [%d]\n", _name, _fsid);
00051             f_mount(i, &_fs);
00052             return;
00053         }
00054     }
00055     error("Couldn't create %s in FATFileSystem::FATFileSystem\n",n);
00056 }
00057     
00058 FATFileSystem::~FATFileSystem() {
00059     for(int i=0; i<_DRIVES; i++) {
00060         if(_ffs[i] == this) {
00061             _ffs[i] = 0;
00062             f_mount(i, NULL);
00063         }
00064     }
00065 }
00066     
00067 FileHandle *FATFileSystem::open(const char* name, int flags) {
00068     FFSDEBUG("open(%s) on filesystem [%s], drv [%d]\n", name, _name, _fsid);
00069     char n[64];
00070     sprintf(n, "%d:/%s", _fsid, name);
00071 
00072     /* POSIX flags -> FatFS open mode */
00073     BYTE openmode;
00074     if(flags & O_RDWR) {
00075         openmode = FA_READ|FA_WRITE;
00076     } else if(flags & O_WRONLY) {
00077         openmode = FA_WRITE;
00078     } else {
00079         openmode = FA_READ;
00080     }
00081     if(flags & O_CREAT) {
00082         if(flags & O_TRUNC) {
00083             openmode |= FA_CREATE_ALWAYS;
00084         } else {
00085             openmode |= FA_OPEN_ALWAYS;
00086         }
00087     }
00088 
00089     FIL_t fh;
00090     FRESULT res = f_open(&fh, n, openmode);
00091     if(res) {
00092         FFSDEBUG("f_open('w') failed (%d, %s)\n", res, FR_ERRORS[res]);
00093         return NULL;
00094     }
00095     if(flags & O_APPEND) {
00096         f_lseek(&fh, fh.fsize);
00097     }
00098     return new FATFileHandle(fh);
00099 }
00100     
00101 int FATFileSystem::remove(const char *filename) {
00102     FRESULT res = f_unlink(filename);
00103     if(res) {
00104         FFSDEBUG("f_unlink() failed (%d, %s)\n", res, FR_ERRORS[res]);
00105         return -1;
00106     }
00107     return 0;
00108 }
00109 
00110 int FATFileSystem::format() {
00111     FFSDEBUG("format()\n");
00112     FRESULT res = f_mkfs(_fsid, 0, 512); // Logical drive number, Partitioning rule, Allocation unit size (bytes per cluster)
00113     if(res) {
00114         FFSDEBUG("f_mkfs() failed (%d, %s)\n", res, FR_ERRORS[res]);
00115         return -1;
00116     }
00117     return 0;
00118 }
00119 
00120 DirHandle *FATFileSystem::opendir(const char *name) {
00121     DIR_t dir;
00122     FRESULT res = f_opendir(&dir, name);
00123     if(res != 0) {
00124         return NULL;
00125     }
00126     return new FATDirHandle(dir);
00127 }
00128 
00129 int FATFileSystem::mkdir(const char *name, mode_t mode) {
00130     FRESULT res = f_mkdir(name);
00131     return res == 0 ? 0 : -1;
00132 }
00133 
00134 } // namespace mbed