pff.cpp

00001 /*----------------------------------------------------------------------------/
00002 /  Petit FatFs - FAT file system module  R0.02                 (C)ChaN, 2009
00003 /-----------------------------------------------------------------------------/
00004 / Petit FatFs module is an open source software to implement FAT file system to
00005 / small embedded systems. This is a free software and is opened for education,
00006 / research and commercial developments under license policy of following trems.
00007 /
00008 /  Copyright (C) 2009, ChaN, all right reserved.
00009 /
00010 / * The Petit FatFs module is a free software and there is NO WARRANTY.
00011 / * No restriction on use. You can use, modify and redistribute it for
00012 /   personal, non-profit or commercial use UNDER YOUR RESPONSIBILITY.
00013 / * Redistributions of source code must retain the above copyright notice.
00014 /
00015 /-----------------------------------------------------------------------------/
00016 / Jun 15,'09  R0.01a  First release. (Branched from FatFs R0.07b.)
00017 /
00018 / Dec 14,'09  R0.02   Added multiple code page support.
00019 /                     Added write funciton.
00020 /                     Changed stream read mode interface.
00021 /----------------------------------------------------------------------------*/
00022 
00023 #include "pff.h"        /* Petit FatFs configurations and declarations */
00024 #include "diskio.h"        /* Declarations of low level disk I/O functions */
00025 
00026 
00027 /*--------------------------------------------------------------------------
00028 
00029    Private Functions
00030 
00031 ---------------------------------------------------------------------------*/
00032 
00033 
00034 
00035 /*-----------------------------------------------------------------------*/
00036 /* String functions                                                      */
00037 /*-----------------------------------------------------------------------*/
00038 
00039 /* Fill memory */
00040 void PetitFileSystem::mem_set (void* dst, int val, int cnt) {
00041     char *d = (char*)dst;
00042     while (cnt--) *d++ = (char)val;
00043 }
00044 
00045 /* Compare memory to memory */
00046 int PetitFileSystem::mem_cmp (const void* dst, const void* src, int cnt) {
00047     const char *d = (const char *)dst, *s = (const char *)src;
00048     int r = 0;
00049     while (cnt-- && (r = *d++ - *s++) == 0) ;
00050     return r;
00051 }
00052 
00053 
00054 
00055 /*-----------------------------------------------------------------------*/
00056 /* FAT access - Read value of a FAT entry                                */
00057 /*-----------------------------------------------------------------------*/
00058 
00059 CLUST PetitFileSystem::get_fat (    /* 1:IO error, Else:Cluster status */
00060     FATFS *fs,
00061     CLUST clst    /* Cluster# to get the link information */
00062 ) {
00063     WORD wc, bc, ofs;
00064     BYTE buf[4];
00065 
00066     if (clst < 2 || clst >= fs->max_clust)    /* Range check */
00067         return 1;
00068 
00069     switch (fs->fs_type) {
00070         case FS_FAT12 :
00071             bc = (WORD)clst;
00072             bc += bc / 2;
00073             ofs = bc % 512;
00074             bc /= 512;
00075             if (ofs != 511) {
00076                 if (disk_readp(buf, fs->fatbase + bc, ofs, 2)) break;
00077             } else {
00078                 if (disk_readp(buf, fs->fatbase + bc, 511, 1)) break;
00079                 if (disk_readp(buf+1, fs->fatbase + bc + 1, 0, 1)) break;
00080             }
00081             wc = LD_WORD(buf);
00082             return (clst & 1) ? (wc >> 4) : (wc & 0xFFF);
00083 
00084         case FS_FAT16 :
00085             if (disk_readp(buf, fs->fatbase + clst / 256, (WORD)(((WORD)clst % 256) * 2), 2)) break;
00086             return LD_WORD(buf);
00087 #if _FS_FAT32
00088         case FS_FAT32 :
00089             if (disk_readp(buf, fs->fatbase + clst / 128, (WORD)(((WORD)clst % 128) * 4), 4)) break;
00090             return LD_DWORD(buf) & 0x0FFFFFFF;
00091 #endif
00092     }
00093 
00094     return 1;    /* An error occured at the disk I/O layer */
00095 }
00096 
00097 
00098 
00099 
00100 /*-----------------------------------------------------------------------*/
00101 /* Get sector# from cluster#                                             */
00102 /*-----------------------------------------------------------------------*/
00103 
00104 DWORD PetitFileSystem::clust2sect (    /* !=0: Sector number, 0: Failed - invalid cluster# */
00105     FATFS *fs, CLUST clst        /* Cluster# to be converted */
00106 ) {
00107 
00108     clst -= 2;
00109     if (clst >= (fs->max_clust - 2)) return 0;        /* Invalid cluster# */
00110     return (DWORD)clst * fs->csize + fs->database;
00111 }
00112 
00113 
00114 
00115 
00116 /*-----------------------------------------------------------------------*/
00117 /* Directory handling - Rewind directory index                           */
00118 /*-----------------------------------------------------------------------*/
00119 
00120 PetitFileSystem::FRESULT PetitFileSystem::dir_rewind ( FATFS *fs,
00121         FATDIR *dj            /* Pointer to directory object */
00122                                                      ) {
00123     CLUST clst;
00124 
00125 
00126 
00127     dj->index = 0;
00128     clst = dj->sclust;
00129     if (clst == 1 || clst >= fs->max_clust)    /* Check start cluster range */
00130         return FR_DISK_ERR;
00131 #if _FS_FAT32
00132     if (!clst && fs->fs_type == FS_FAT32)    /* Replace cluster# 0 with root cluster# if in FAT32 */
00133         clst = fs->dirbase;
00134 #endif
00135     dj->clust = clst;                        /* Current cluster */
00136     dj->sect = clst ? clust2sect(fs, clst) : fs->dirbase;    /* Current sector */
00137 
00138     return FR_OK;    /* Seek succeeded */
00139 }
00140 
00141 
00142 
00143 
00144 /*-----------------------------------------------------------------------*/
00145 /* Directory handling - Move directory index next                        */
00146 /*-----------------------------------------------------------------------*/
00147 
00148 PetitFileSystem::FRESULT PetitFileSystem::dir_next (    /* FR_OK:Succeeded, FR_NO_FILE:End of table */
00149     FATFS *fs,
00150     FATDIR *dj            /* Pointer to directory object */
00151 ) {
00152     CLUST clst;
00153     WORD i;
00154 
00155 
00156     i = dj->index + 1;
00157     if (!i || !dj->sect)    /* Report EOT when index has reached 65535 */
00158         return FR_NO_FILE;
00159 
00160     if (!(i & (16-1))) {    /* Sector changed? */
00161         dj->sect++;            /* Next sector */
00162 
00163         if (dj->clust == 0) {    /* Static table */
00164             if (i >= fs->n_rootdir)    /* Report EOT when end of table */
00165                 return FR_NO_FILE;
00166         } else {                   /* Dynamic table */
00167             if (((i / 16) & (fs->csize-1)) == 0) {    /* Cluster changed? */
00168                 clst = get_fat(fs, dj->clust);        /* Get next cluster */
00169                 if (clst <= 1) return FR_DISK_ERR;
00170                 if (clst >= fs->max_clust)        /* When it reached end of dynamic table */
00171                     return FR_NO_FILE;            /* Report EOT */
00172                 dj->clust = clst;                /* Initialize data for new cluster */
00173                 dj->sect = clust2sect(fs, clst);
00174             }
00175         }
00176     }
00177 
00178     dj->index = i;
00179 
00180     return FR_OK;
00181 }
00182 
00183 
00184 
00185 
00186 /*-----------------------------------------------------------------------*/
00187 /* Directory handling - Find an object in the directory                  */
00188 /*-----------------------------------------------------------------------*/
00189 
00190 PetitFileSystem::FRESULT PetitFileSystem::dir_find (
00191     FATFS *fs,
00192     FATDIR *dj            /* Pointer to the directory object linked to the file name */
00193 ) {
00194     FRESULT res;
00195     BYTE c, *dir;
00196 
00197 
00198     res = dir_rewind(fs, dj);            /* Rewind directory object */
00199     if (res != FR_OK) return res;
00200 
00201     dir = fs->buf;
00202     do {
00203         res = disk_readp(dir, dj->sect, (WORD)((dj->index % 16) * 32), 32)    /* Read an entry */
00204               ? FR_DISK_ERR : FR_OK;
00205         if (res != FR_OK) break;
00206         c = dir[DIR_Name];    /* First character */
00207         if (c == 0) {
00208             res = FR_NO_FILE;    /* Reached to end of table */
00209             break;
00210         }
00211         if (!(dir[DIR_Attr] & AM_VOL) && !mem_cmp(dir, dj->fn, 11)) /* Is it a valid entry? */
00212             break;
00213         res = dir_next(fs, dj);                            /* Next entry */
00214     } while (res == FR_OK);
00215 
00216     return res;
00217 }
00218 
00219 
00220 
00221 
00222 /*-----------------------------------------------------------------------*/
00223 /* Read an object from the directory                                     */
00224 /*-----------------------------------------------------------------------*/
00225 #if _USE_DIR
00226 PetitFileSystem::FRESULT PetitFileSystem::dir_read (
00227     FATFS *fs,
00228     FATDIR *dj            /* Pointer to the directory object to store read object name */
00229 ) {
00230     FRESULT res;
00231     BYTE a, c, *dir;
00232 
00233 
00234     res = FR_NO_FILE;
00235     dir = fs->buf;
00236     while (dj->sect) {
00237         res = disk_readp(dir, dj->sect, (WORD)((dj->index % 16) * 32), 32)    /* Read an entry */
00238               ? FR_DISK_ERR : FR_OK;
00239         if (res != FR_OK) break;
00240         c = dir[DIR_Name];
00241         if (c == 0) {
00242             res = FR_NO_FILE;    /* Reached to end of table */
00243             break;
00244         }
00245         a = dir[DIR_Attr] & AM_MASK;
00246         if (c != 0xE5 && c != '.' && !(a & AM_VOL))    /* Is it a valid entry? */
00247             break;
00248         res = dir_next(fs, dj);                /* Next entry */
00249         if (res != FR_OK) break;
00250     }
00251 
00252     if (res != FR_OK) dj->sect = 0;
00253 
00254     return res;
00255 }
00256 #endif
00257 
00258 
00259 
00260 /*-----------------------------------------------------------------------*/
00261 /* Pick a segment and create the object name in directory form           */
00262 /*-----------------------------------------------------------------------*/
00263 
00264 #ifdef _EXCVT
00265 static const BYTE cvt[] = _EXCVT;
00266 #endif
00267 
00268 PetitFileSystem::FRESULT PetitFileSystem::create_name (
00269     FATDIR *dj,            /* Pointer to the directory object */
00270     const char **path    /* Pointer to pointer to the segment in the path string */
00271 ) {
00272     BYTE c, d, ni, si, i, *sfn;
00273     const char *p;
00274 
00275     /* Create file name in directory form */
00276     sfn = dj->fn;
00277     mem_set(sfn, ' ', 11);
00278     si = i = 0;
00279     ni = 8;
00280     p = *path;
00281     for (;;) {
00282         c = p[si++];
00283         if (c <= ' ' || c == '/') break;    /* Break on end of segment */
00284         if (c == '.' || i >= ni) {
00285             if (ni != 8 || c != '.') break;
00286             i = 8;
00287             ni = 11;
00288             continue;
00289         }
00290 #ifdef _EXCVT
00291         if (c >= 0x80)                    /* To upper extended char (SBCS) */
00292             c = cvt[c - 0x80];
00293 #endif
00294         if (IsDBCS1(c) && i >= ni - 1) {    /* DBC 1st byte? */
00295             d = p[si++];                    /* Get 2nd byte */
00296             sfn[i++] = c;
00297             sfn[i++] = d;
00298         } else {                        /* Single byte code */
00299             if (IsLower(c)) c -= 0x20;    /* toupper */
00300             sfn[i++] = c;
00301         }
00302     }
00303     *path = &p[si];                        /* Rerurn pointer to the next segment */
00304 
00305     sfn[11] = (c <= ' ') ? 1 : 0;        /* Set last segment flag if end of path */
00306 
00307     return FR_OK;
00308 }
00309 
00310 
00311 
00312 
00313 /*-----------------------------------------------------------------------*/
00314 /* Get file information from directory entry                             */
00315 /*-----------------------------------------------------------------------*/
00316 #if _USE_DIR
00317 void PetitFileSystem::get_fileinfo (        /* No return code */
00318     FATFS *fs,
00319     FATDIR *dj,            /* Pointer to the directory object */
00320     FILINFO *fno         /* Pointer to store the file information */
00321 ) {
00322     BYTE i, c, *dir;
00323     char *p;
00324 
00325 
00326     p = fno->fname;
00327     if (dj->sect) {
00328         dir = fs->buf;
00329         for (i = 0; i < 8; i++) {    /* Copy file name body */
00330             c = dir[i];
00331             if (c == ' ') break;
00332             if (c == 0x05) c = 0xE5;
00333             *p++ = c;
00334         }
00335         if (dir[8] != ' ') {        /* Copy file name extension */
00336             *p++ = '.';
00337             for (i = 8; i < 11; i++) {
00338                 c = dir[i];
00339                 if (c == ' ') break;
00340                 *p++ = c;
00341             }
00342         }
00343         fno->fattrib = dir[DIR_Attr];                /* Attribute */
00344         fno->fsize = LD_DWORD(dir+DIR_FileSize);    /* Size */
00345         fno->fdate = LD_WORD(dir+DIR_WrtDate);        /* Date */
00346         fno->ftime = LD_WORD(dir+DIR_WrtTime);        /* Time */
00347     }
00348     *p = 0;
00349 }
00350 #endif /* _USE_DIR */
00351 
00352 
00353 
00354 /*-----------------------------------------------------------------------*/
00355 /* Follow a file path                                                    */
00356 /*-----------------------------------------------------------------------*/
00357 
00358 PetitFileSystem::FRESULT PetitFileSystem::follow_path (    /* FR_OK(0): successful, !=0: error code */
00359     FATFS *fs,
00360     FATDIR *dj,            /* Directory object to return last directory and found object */
00361     const char *path    /* Full-path string to find a file or directory */
00362 ) {
00363     FRESULT res;
00364     BYTE *dir;
00365 
00366 
00367     while (*path == ' ') path++;        /* Skip leading spaces */
00368     if (*path == '/') path++;            /* Strip heading separator */
00369     dj->sclust = 0;                        /* Set start directory (always root dir) */
00370 
00371     if ((BYTE)*path <= ' ') {            /* Null path means the root directory */
00372         res = dir_rewind(fs, dj);
00373         fs->buf[0] = 0;
00374 
00375     } else {                            /* Follow path */
00376         for (;;) {
00377             res = create_name(dj, &path);    /* Get a segment */
00378             if (res != FR_OK) break;
00379             res = dir_find(fs, dj);                /* Find it */
00380             if (res != FR_OK) {                /* Could not find the object */
00381                 if (res == FR_NO_FILE && !*(dj->fn+11))
00382                     res = FR_NO_PATH;
00383                 break;
00384             }
00385             if (*(dj->fn+11)) break;        /* Last segment match. Function completed. */
00386             dir = fs->buf;                /* There is next segment. Follow the sub directory */
00387             if (!(dir[DIR_Attr] & AM_DIR)) { /* Cannot follow because it is a file */
00388                 res = FR_NO_PATH;
00389                 break;
00390             }
00391             dj->sclust =
00392 #if _FS_FAT32
00393                 ((DWORD)LD_WORD(dir+DIR_FstClusHI) << 16) |
00394 #endif
00395                 LD_WORD(dir+DIR_FstClusLO);
00396         }
00397     }
00398 
00399     return res;
00400 }
00401 
00402 
00403 
00404 
00405 /*-----------------------------------------------------------------------*/
00406 /* Check a sector if it is an FAT boot record                            */
00407 /*-----------------------------------------------------------------------*/
00408 
00409 BYTE PetitFileSystem::check_fs (    /* 0:The FAT boot record, 1:Valid boot record but not an FAT, 2:Not a boot record, 3:Error */
00410     BYTE *buf,    /* Working buffer */
00411     DWORD sect    /* Sector# (lba) to check if it is an FAT boot record or not */
00412 ) {
00413     if (disk_readp(buf, sect, 510, 2))        /* Read the boot sector */
00414         return 3;
00415     if (LD_WORD(buf) != 0xAA55)                /* Check record signature */
00416         return 2;
00417 
00418     if (!disk_readp(buf, sect, BS_FilSysType, 2) && LD_WORD(buf) == 0x4146)    /* Check FAT12/16 */
00419         return 0;
00420 #if _FS_FAT32
00421     if (!disk_readp(buf, sect, BS_FilSysType32, 2) && LD_WORD(buf) == 0x4146)    /* Check FAT32 */
00422         return 0;
00423 #endif
00424     return 1;
00425 }
00426 
00427 
00428 
00429 
00430 /*--------------------------------------------------------------------------
00431 
00432    Public Functions
00433 
00434 --------------------------------------------------------------------------*/
00435 
00436 
00437 
00438 /*-----------------------------------------------------------------------*/
00439 /* Mount/Unmount a Locical Drive                                         */
00440 /*-----------------------------------------------------------------------*/
00441 
00442 PetitFileSystem::FRESULT PetitFileSystem::unmount () {
00443     FatFs = 0;
00444     return FR_OK;                /* Unregister fs object */
00445 }
00446 
00447 PetitFileSystem::FRESULT PetitFileSystem::mount () {
00448     BYTE fmt, buf[36];
00449     DWORD bsect, fsize, tsect, mclst;
00450     FATFS *fs = &FileSystemObject;
00451 
00452     if (disk_initialize() & STA_NOINIT)    /* Check if the drive is ready or not */
00453         return FR_NOT_READY;
00454 
00455     /* Search FAT partition on the drive */
00456     bsect = 0;
00457     fmt = check_fs(buf, bsect);            /* Check sector 0 as an SFD format */
00458     if (fmt == 1) {                        /* Not an FAT boot record, it may be FDISK format */
00459         /* Check a partition listed in top of the partition table */
00460         if (disk_readp(buf, bsect, MBR_Table, 16)) {    /* 1st partition entry */
00461             fmt = 3;
00462         } else {
00463             if (buf[4]) {                    /* Is the partition existing? */
00464                 bsect = LD_DWORD(&buf[8]);    /* Partition offset in LBA */
00465                 fmt = check_fs(buf, bsect);    /* Check the partition */
00466             }
00467         }
00468     }
00469     if (fmt == 3) return FR_DISK_ERR;
00470     if (fmt) return FR_NO_FILESYSTEM;    /* No valid FAT patition is found */
00471 
00472     /* Initialize the file system object */
00473     if (disk_readp(buf, bsect, 13, sizeof(buf))) return FR_DISK_ERR;
00474 
00475     fsize = LD_WORD(buf+BPB_FATSz16-13);                /* Number of sectors per FAT */
00476     if (!fsize) fsize = LD_DWORD(buf+BPB_FATSz32-13);
00477 
00478     fsize *= buf[BPB_NumFATs-13];                        /* Number of sectors in FAT area */
00479     fs->fatbase = bsect + LD_WORD(buf+BPB_RsvdSecCnt-13); /* FAT start sector (lba) */
00480     fs->csize = buf[BPB_SecPerClus-13];                    /* Number of sectors per cluster */
00481     fs->n_rootdir = LD_WORD(buf+BPB_RootEntCnt-13);        /* Nmuber of root directory entries */
00482     tsect = LD_WORD(buf+BPB_TotSec16-13);                /* Number of sectors on the file system */
00483     if (!tsect) tsect = LD_DWORD(buf+BPB_TotSec32-13);
00484     mclst = (tsect                        /* Last cluster# + 1 */
00485              - LD_WORD(buf+BPB_RsvdSecCnt-13) - fsize - fs->n_rootdir / 16
00486             ) / fs->csize + 2;
00487     fs->max_clust = (CLUST)mclst;
00488 
00489     fmt = FS_FAT12;                            /* Determine the FAT sub type */
00490     if (mclst >= 0xFF7) fmt = FS_FAT16;        /* Number of clusters >= 0xFF5 */
00491     if (mclst >= 0xFFF7)                    /* Number of clusters >= 0xFFF5 */
00492 #if _FS_FAT32
00493         fmt = FS_FAT32;
00494 #else
00495         return FR_NO_FILESYSTEM;
00496 #endif
00497 
00498     fs->fs_type = fmt;        /* FAT sub-type */
00499 #if _FS_FAT32
00500     if (fmt == FS_FAT32)
00501         fs->dirbase = LD_DWORD(buf+(BPB_RootClus-13));    /* Root directory start cluster */
00502     else
00503 #endif
00504         fs->dirbase = fs->fatbase + fsize;                /* Root directory start sector (lba) */
00505     fs->database = fs->fatbase + fsize + fs->n_rootdir / 16;    /* Data start sector (lba) */
00506 
00507     fs->flag = 0;
00508     FatFs = fs;
00509 
00510     return FR_OK;
00511 }
00512 
00513 
00514 
00515 
00516 /*-----------------------------------------------------------------------*/
00517 /* Open or Create a File                                                 */
00518 /*-----------------------------------------------------------------------*/
00519 
00520 PetitFileSystem::FRESULT PetitFileSystem::open (
00521     const char *path    /* Pointer to the file name */
00522 ) {
00523     FRESULT res;
00524     FATDIR dj;
00525     BYTE sp[12], dir[32];
00526 
00527 
00528     if (!FatFs)                        /* Check file system */
00529         return FR_NOT_ENABLED;
00530 
00531     FatFs->flag = 0;
00532     FatFs->buf = dir;
00533     dj.fn = sp;
00534     res = follow_path(FatFs, &dj, path);    /* Follow the file path */
00535     if (res != FR_OK) return res;    /* Follow failed */
00536     if (!dir[0] || (dir[DIR_Attr] & AM_DIR))    /* It is a directory */
00537         return FR_NO_FILE;
00538 
00539     FatFs->org_clust =                        /* File start cluster */
00540 #if _FS_FAT32
00541         ((DWORD)LD_WORD(dir+DIR_FstClusHI) << 16) |
00542 #endif
00543         LD_WORD(dir+DIR_FstClusLO);
00544     FatFs->fsize = LD_DWORD(dir+DIR_FileSize);    /* File size */
00545     FatFs->fptr = 0;                        /* File pointer */
00546     FatFs->flag = FA_OPENED;
00547 
00548     return FR_OK;
00549 }
00550 
00551 
00552 
00553 
00554 /*-----------------------------------------------------------------------*/
00555 /* Read File                                                             */
00556 /*-----------------------------------------------------------------------*/
00557 #if _USE_READ
00558 
00559 PetitFileSystem::FRESULT PetitFileSystem::read (
00560     void* buff,        /* Pointer to the read buffer (NULL:Forward data to the stream)*/
00561     WORD btr,        /* Number of bytes to read */
00562     WORD* br        /* Pointer to number of bytes read */
00563 ) {
00564     DRESULT dr;
00565     CLUST clst;
00566     DWORD sect, remain;
00567     BYTE *rbuff = (BYTE *)buff;
00568     WORD rcnt;
00569     FATFS *fs = FatFs;
00570 
00571 
00572     *br = 0;
00573     if (!fs) return FR_NOT_ENABLED;        /* Check file system */
00574     if (!(fs->flag & FA_OPENED))        /* Check if opened */
00575         return FR_NOT_OPENED;
00576 
00577     remain = fs->fsize - fs->fptr;
00578     if (btr > remain) btr = (WORD)remain;            /* Truncate btr by remaining bytes */
00579 
00580     while (btr)    {                                    /* Repeat until all data transferred */
00581         if ((fs->fptr % 512) == 0) {                /* On the sector boundary? */
00582             if ((fs->fptr / 512 % fs->csize) == 0) {    /* On the cluster boundary? */
00583                 clst = (fs->fptr == 0) ?            /* On the top of the file? */
00584                        fs->org_clust : get_fat(fs, fs->curr_clust);
00585                 if (clst <= 1) goto fr_abort;
00586                 fs->curr_clust = clst;                /* Update current cluster */
00587                 fs->csect = 0;                        /* Reset sector offset in the cluster */
00588             }
00589             sect = clust2sect(fs, fs->curr_clust);        /* Get current sector */
00590             if (!sect) goto fr_abort;
00591             fs->dsect = sect + fs->csect++;
00592         }
00593         rcnt = 512 - ((WORD)fs->fptr % 512);        /* Get partial sector data from sector buffer */
00594         if (rcnt > btr) rcnt = btr;
00595         dr = disk_readp(!buff ? 0 : rbuff, fs->dsect, (WORD)(fs->fptr % 512), rcnt);
00596         if (dr) goto fr_abort;
00597         fs->fptr += rcnt;
00598         rbuff += rcnt;            /* Update pointers and counters */
00599         btr -= rcnt;
00600         *br += rcnt;
00601     }
00602 
00603     return FR_OK;
00604 
00605 fr_abort:
00606     fs->flag = 0;
00607     return FR_DISK_ERR;
00608 }
00609 #endif
00610 
00611 
00612 
00613 /*-----------------------------------------------------------------------*/
00614 /* Write File                                                            */
00615 /*-----------------------------------------------------------------------*/
00616 #if _USE_WRITE
00617 
00618 PetitFileSystem::FRESULT PetitFileSystem::write (
00619     const void* buff,    /* Pointer to the data to be written */
00620     WORD btw,            /* Number of bytes to write (0:Finalize the current write operation) */
00621     WORD* bw            /* Pointer to number of bytes written */
00622 ) {
00623     CLUST clst;
00624     DWORD sect, remain;
00625     const BYTE *p = (const BYTE *)buff;
00626     WORD wcnt;
00627     FATFS *fs = FatFs;
00628 
00629 
00630     *bw = 0;
00631     if (!fs) return FR_NOT_ENABLED;        /* Check file system */
00632     if (!(fs->flag & FA_OPENED))        /* Check if opened */
00633         return FR_NOT_OPENED;
00634 
00635     if (!btw) {        /* Finalize request */
00636         if ((fs->flag & FA__WIP) && disk_writep(0, 0)) goto fw_abort;
00637         fs->flag &= ~FA__WIP;
00638         return FR_OK;
00639     } else {        /* Write data request */
00640         if (!(fs->flag & FA__WIP))        /* Round down fptr to the sector boundary */
00641             fs->fptr &= 0xFFFFFE00;
00642     }
00643     remain = fs->fsize - fs->fptr;
00644     if (btw > remain) btw = (WORD)remain;            /* Truncate btw by remaining bytes */
00645 
00646     while (btw)    {                                    /* Repeat until all data transferred */
00647         if (((WORD)fs->fptr % 512) == 0) {                /* On the sector boundary? */
00648             if ((fs->fptr / 512 % fs->csize) == 0) {    /* On the cluster boundary? */
00649                 clst = (fs->fptr == 0) ?            /* On the top of the file? */
00650                        fs->org_clust : get_fat(fs, fs->curr_clust);
00651                 if (clst <= 1) goto fw_abort;
00652                 fs->curr_clust = clst;                /* Update current cluster */
00653                 fs->csect = 0;                        /* Reset sector offset in the cluster */
00654             }
00655             sect = clust2sect(fs, fs->curr_clust);        /* Get current sector */
00656             if (!sect) goto fw_abort;
00657             fs->dsect = sect + fs->csect++;
00658             if (disk_writep(0, fs->dsect)) goto fw_abort;    /* Initiate a sector write operation */
00659             fs->flag |= FA__WIP;
00660         }
00661         wcnt = 512 - ((WORD)fs->fptr % 512);        /* Number of bytes to write to the sector */
00662         if (wcnt > btw) wcnt = btw;
00663         if (disk_writep(p, wcnt)) goto fw_abort;    /* Send data to the sector */
00664         fs->fptr += wcnt;
00665         p += wcnt;                /* Update pointers and counters */
00666         btw -= wcnt;
00667         *bw += wcnt;
00668         if (((WORD)fs->fptr % 512) == 0) {
00669             if (disk_writep(0, 0)) goto fw_abort;    /* Finalize the currtent secter write operation */
00670             fs->flag &= ~FA__WIP;
00671         }
00672     }
00673 
00674     return FR_OK;
00675 
00676 fw_abort:
00677     fs->flag = 0;
00678     return FR_DISK_ERR;
00679 }
00680 #endif
00681 
00682 
00683 
00684 /*-----------------------------------------------------------------------*/
00685 /* Seek File R/W Pointer                                                 */
00686 /*-----------------------------------------------------------------------*/
00687 #if _USE_LSEEK
00688 
00689 PetitFileSystem::FRESULT PetitFileSystem::lseek (
00690     DWORD ofs        /* File pointer from top of file */
00691 ) {
00692     CLUST clst;
00693     DWORD bcs, sect, ifptr;
00694     FATFS *fs = FatFs;
00695 
00696 
00697     if (!fs) return FR_NOT_ENABLED;        /* Check file system */
00698     if (!(fs->flag & FA_OPENED))        /* Check if opened */
00699         return FR_NOT_OPENED;
00700 
00701     if (ofs > fs->fsize) ofs = fs->fsize;    /* Clip offset with the file size */
00702     ifptr = fs->fptr;
00703     fs->fptr = 0;
00704     if (ofs > 0) {
00705         bcs = (DWORD)fs->csize * 512;    /* Cluster size (byte) */
00706         if (ifptr > 0 &&
00707                 (ofs - 1) / bcs >= (ifptr - 1) / bcs) {    /* When seek to same or following cluster, */
00708             fs->fptr = (ifptr - 1) & ~(bcs - 1);    /* start from the current cluster */
00709             ofs -= fs->fptr;
00710             clst = fs->curr_clust;
00711         } else {                            /* When seek to back cluster, */
00712             clst = fs->org_clust;            /* start from the first cluster */
00713             fs->curr_clust = clst;
00714         }
00715         while (ofs > bcs) {                /* Cluster following loop */
00716             clst = get_fat(fs, clst);        /* Follow cluster chain */
00717             if (clst <= 1 || clst >= fs->max_clust) goto fe_abort;
00718             fs->curr_clust = clst;
00719             fs->fptr += bcs;
00720             ofs -= bcs;
00721         }
00722         fs->fptr += ofs;
00723         sect = clust2sect(fs, clst);        /* Current sector */
00724         if (!sect) goto fe_abort;
00725         fs->csect = (BYTE)(ofs / 512);    /* Sector offset in the cluster */
00726         if (ofs % 512)
00727             fs->dsect = sect + fs->csect++;
00728     }
00729 
00730     return FR_OK;
00731 
00732 fe_abort:
00733     fs->flag = 0;
00734     return FR_DISK_ERR;
00735 }
00736 #endif
00737 
00738 
00739 
00740 /*-----------------------------------------------------------------------*/
00741 /* Create a Directroy Object                                             */
00742 /*-----------------------------------------------------------------------*/
00743 #if _USE_DIR
00744 
00745 PetitFileSystem::FRESULT PetitFileSystem::opendir (
00746     const char *path    /* Pointer to the directory path */
00747 ) {
00748     FRESULT res;
00749     BYTE sp[12], dir[32];
00750     FATDIR *dj = &DirectoryObject;
00751 
00752     if (!FatFs) {                /* Check file system */
00753         res = FR_NOT_ENABLED;
00754     } else {
00755         FatFs->buf = dir;
00756         dj->fn = sp;
00757         res = follow_path(FatFs, dj, path);            /* Follow the path to the directory */
00758         if (res == FR_OK) {                        /* Follow completed */
00759             if (dir[0]) {                        /* It is not the root dir */
00760                 if (dir[DIR_Attr] & AM_DIR) {    /* The object is a directory */
00761                     dj->sclust =
00762 #if _FS_FAT32
00763                         ((DWORD)LD_WORD(dir+DIR_FstClusHI) << 16) |
00764 #endif
00765                         LD_WORD(dir+DIR_FstClusLO);
00766                 } else {                        /* The object is not a directory */
00767                     res = FR_NO_PATH;
00768                 }
00769             }
00770             if (res == FR_OK)
00771                 res = dir_rewind(FatFs, dj);            /* Rewind dir */
00772         }
00773         if (res == FR_NO_FILE) res = FR_NO_PATH;
00774     }
00775 
00776     return res;
00777 }
00778 
00779 
00780 
00781 
00782 /*-----------------------------------------------------------------------*/
00783 /* Read Directory Entry in Sequense                                      */
00784 /*-----------------------------------------------------------------------*/
00785 
00786 PetitFileSystem::FRESULT PetitFileSystem::readdir (
00787     FILINFO *fno        /* Pointer to file information to return */
00788 ) {
00789     FRESULT res;
00790     BYTE sp[12], dir[32];
00791     FATDIR *dj = &DirectoryObject;
00792 
00793     if (!FatFs) {                /* Check file system */
00794         res = FR_NOT_ENABLED;
00795     } else {
00796         FatFs->buf = dir;
00797         dj->fn = sp;
00798         if (!fno) {
00799             res = dir_rewind(FatFs, dj);
00800         } else {
00801             res = dir_read(FatFs, dj);
00802             if (res == FR_NO_FILE) {
00803                 dj->sect = 0;
00804                 res = FR_OK;
00805             }
00806             if (res == FR_OK) {                /* A valid entry is found */
00807                 get_fileinfo(FatFs, dj, fno);        /* Get the object information */
00808                 res = dir_next(FatFs, dj);            /* Increment index for next */
00809                 if (res == FR_NO_FILE) {
00810                     dj->sect = 0;
00811                     res = FR_OK;
00812                 }
00813             }
00814         }
00815     }
00816 
00817     return res;
00818 }
00819 
00820 #endif /* _USE_DIR */
00821