Jonne Valola
PokittoLib is the library needed for programming the Pokitto DIY game console (www.pokitto.com)
Dependents: YATTT sd_map_test cPong SnowDemo ... more
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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 00024 #include "pff.h" /* Petit FatFs configurations and declarations */ 00025 #include "diskio.h" /* Declarations of low level disk I/O functions */ 00026 00027 namespace PFFS { 00028 00029 /*-------------------------------------------------------------------------- 00030 00031 Private Functions 00032 00033 ---------------------------------------------------------------------------*/ 00034 00035 static 00036 FATFS *FatFs; /* Pointer to the file system object (logical drive) */ 00037 00038 00039 00040 /*-----------------------------------------------------------------------*/ 00041 /* String functions */ 00042 /*-----------------------------------------------------------------------*/ 00043 00044 /* Fill memory */ 00045 static 00046 void mem_set (void* dst, int val, int cnt) { 00047 char *d = (char*)dst; 00048 while (cnt--) *d++ = (char)val; 00049 } 00050 00051 /* Compare memory to memory */ 00052 static 00053 int mem_cmp (const void* dst, const void* src, int cnt) { 00054 const char *d = (const char *)dst, *s = (const char *)src; 00055 int r = 0; 00056 while (cnt-- && (r = *d++ - *s++) == 0) ; 00057 return r; 00058 } 00059 00060 00061 00062 /*-----------------------------------------------------------------------*/ 00063 /* FAT access - Read value of a FAT entry */ 00064 /*-----------------------------------------------------------------------*/ 00065 00066 static 00067 CLUST get_fat ( /* 1:IO error, Else:Cluster status */ 00068 CLUST clst /* Cluster# to get the link information */ 00069 ) { 00070 WORD wc, bc, ofs; 00071 BYTE buf[4]; 00072 FATFS *fs = FatFs; 00073 00074 00075 if (clst < 2 || clst >= fs->max_clust) /* Range check */ 00076 return 1; 00077 00078 switch (fs->fs_type) { 00079 case FS_FAT12 : 00080 bc = (WORD)clst; 00081 bc += bc / 2; 00082 ofs = bc % 512; 00083 bc /= 512; 00084 if (ofs != 511) { 00085 if (disk_readp(buf, fs->fatbase + bc, ofs, 2)) break; 00086 } else { 00087 if (disk_readp(buf, fs->fatbase + bc, 511, 1)) break; 00088 if (disk_readp(buf+1, fs->fatbase + bc + 1, 0, 1)) break; 00089 } 00090 wc = LD_WORD(buf); 00091 return (clst & 1) ? (wc >> 4) : (wc & 0xFFF); 00092 00093 case FS_FAT16 : 00094 if (disk_readp(buf, fs->fatbase + clst / 256, (WORD)(((WORD)clst % 256) * 2), 2)) break; 00095 return LD_WORD(buf); 00096 #if _FS_FAT32 00097 case FS_FAT32 : 00098 if (disk_readp(buf, fs->fatbase + clst / 128, (WORD)(((WORD)clst % 128) * 4), 4)) break; 00099 return ((WORD)(((WORD)*(BYTE*)((buf)+1)<<8)|(WORD)*(BYTE*)(buf))) & 0x0FFFFFFF; //return LD_DWORD(buf) & 0x0FFFFFFF; //get rid of out of bounds warning in online IDE 00100 #endif 00101 } 00102 00103 return 1; /* An error occured at the disk I/O layer */ 00104 } 00105 00106 00107 00108 00109 /*-----------------------------------------------------------------------*/ 00110 /* Get sector# from cluster# */ 00111 /*-----------------------------------------------------------------------*/ 00112 00113 static 00114 DWORD clust2sect ( /* !=0: Sector number, 0: Failed - invalid cluster# */ 00115 CLUST clst /* Cluster# to be converted */ 00116 ) { 00117 FATFS *fs = FatFs; 00118 00119 00120 clst -= 2; 00121 if (clst >= (fs->max_clust - 2)) return 0; /* Invalid cluster# */ 00122 return (DWORD)clst * fs->csize + fs->database; 00123 } 00124 00125 00126 00127 00128 /*-----------------------------------------------------------------------*/ 00129 /* Directory handling - Rewind directory index */ 00130 /*-----------------------------------------------------------------------*/ 00131 00132 static 00133 FRESULT dir_rewind ( 00134 FATDIR *dj /* Pointer to directory object */ 00135 ) { 00136 CLUST clst; 00137 FATFS *fs = FatFs; 00138 00139 00140 dj->index = 0; 00141 clst = dj->sclust; 00142 if (clst == 1 || clst >= fs->max_clust) /* Check start cluster range */ 00143 return FR_DISK_ERR; 00144 #if _FS_FAT32 00145 if (!clst && fs->fs_type == FS_FAT32) /* Replace cluster# 0 with root cluster# if in FAT32 */ 00146 clst = fs->dirbase; 00147 #endif 00148 dj->clust = clst; /* Current cluster */ 00149 dj->sect = clst ? clust2sect(clst) : fs->dirbase; /* Current sector */ 00150 00151 return FR_OK; /* Seek succeeded */ 00152 } 00153 00154 00155 00156 00157 /*-----------------------------------------------------------------------*/ 00158 /* Directory handling - Move directory index next */ 00159 /*-----------------------------------------------------------------------*/ 00160 00161 static 00162 FRESULT dir_next ( /* FR_OK:Succeeded, FR_NO_FILE:End of table */ 00163 FATDIR *dj /* Pointer to directory object */ 00164 ) { 00165 CLUST clst; 00166 WORD i; 00167 FATFS *fs = FatFs; 00168 00169 00170 i = dj->index + 1; 00171 if (!i || !dj->sect) /* Report EOT when index has reached 65535 */ 00172 return FR_NO_FILE; 00173 00174 if (!(i & (16-1))) { /* Sector changed? */ 00175 dj->sect++; /* Next sector */ 00176 00177 if (dj->clust == 0) { /* Static table */ 00178 if (i >= fs->n_rootdir) /* Report EOT when end of table */ 00179 return FR_NO_FILE; 00180 } else { /* Dynamic table */ 00181 if (((i / 16) & (fs->csize-1)) == 0) { /* Cluster changed? */ 00182 clst = get_fat(dj->clust); /* Get next cluster */ 00183 if (clst <= 1) return FR_DISK_ERR; 00184 if (clst >= fs->max_clust) /* When it reached end of dynamic table */ 00185 return FR_NO_FILE; /* Report EOT */ 00186 dj->clust = clst; /* Initialize data for new cluster */ 00187 dj->sect = clust2sect(clst); 00188 } 00189 } 00190 } 00191 00192 dj->index = i; 00193 00194 return FR_OK; 00195 } 00196 00197 00198 00199 00200 /*-----------------------------------------------------------------------*/ 00201 /* Directory handling - Find an object in the directory */ 00202 /*-----------------------------------------------------------------------*/ 00203 00204 static 00205 FRESULT dir_find ( 00206 FATDIR *dj /* Pointer to the directory object linked to the file name */ 00207 ) { 00208 FRESULT res; 00209 BYTE c, *dir; 00210 00211 00212 res = dir_rewind(dj); /* Rewind directory object */ 00213 if (res != FR_OK) return res; 00214 00215 dir = FatFs->buf; 00216 do { 00217 res = disk_readp(dir, dj->sect, (WORD)((dj->index % 16) * 32), 32) /* Read an entry */ 00218 ? FR_DISK_ERR : FR_OK; 00219 if (res != FR_OK) break; 00220 c = dir[DIR_Name]; /* First character */ 00221 if (c == 0) { 00222 res = FR_NO_FILE; /* Reached to end of table */ 00223 break; 00224 } 00225 if (!(dir[DIR_Attr] & AM_VOL) && !mem_cmp(dir, dj->fn, 11)) /* Is it a valid entry? */ 00226 break; 00227 res = dir_next(dj); /* Next entry */ 00228 } while (res == FR_OK); 00229 00230 return res; 00231 } 00232 00233 00234 00235 00236 /*-----------------------------------------------------------------------*/ 00237 /* Read an object from the directory */ 00238 /*-----------------------------------------------------------------------*/ 00239 #if _USE_DIR 00240 static 00241 FRESULT dir_read ( 00242 FATDIR *dj /* Pointer to the directory object to store read object name */ 00243 ) { 00244 FRESULT res; 00245 BYTE a, c, *dir; 00246 00247 00248 res = FR_NO_FILE; 00249 dir = FatFs->buf; 00250 while (dj->sect) { 00251 res = disk_readp(dir, dj->sect, (WORD)((dj->index % 16) * 32), 32) /* Read an entry */ 00252 ? FR_DISK_ERR : FR_OK; 00253 if (res != FR_OK) break; 00254 c = dir[DIR_Name]; 00255 if (c == 0) { 00256 res = FR_NO_FILE; /* Reached to end of table */ 00257 break; 00258 } 00259 a = dir[DIR_Attr] & AM_MASK; 00260 if (c != 0xE5 && c != '.' && !(a & AM_VOL)) /* Is it a valid entry? */ 00261 break; 00262 res = dir_next(dj); /* Next entry */ 00263 if (res != FR_OK) break; 00264 } 00265 00266 if (res != FR_OK) dj->sect = 0; 00267 00268 return res; 00269 } 00270 #endif 00271 00272 00273 00274 /*-----------------------------------------------------------------------*/ 00275 /* Pick a segment and create the object name in directory form */ 00276 /*-----------------------------------------------------------------------*/ 00277 00278 #ifdef _EXCVT 00279 static const BYTE cvt[] = _EXCVT; 00280 #endif 00281 00282 static 00283 FRESULT create_name ( 00284 FATDIR *dj, /* Pointer to the directory object */ 00285 const char **path /* Pointer to pointer to the segment in the path string */ 00286 ) { 00287 BYTE c, d, ni, si, i, *sfn; 00288 const char *p; 00289 00290 /* Create file name in directory form */ 00291 sfn = dj->fn; 00292 mem_set(sfn, ' ', 11); 00293 si = i = 0; 00294 ni = 8; 00295 p = *path; 00296 for (;;) { 00297 c = p[si++]; 00298 if (c <= ' ' || c == '/') break; /* Break on end of segment */ 00299 if (c == '.' || i >= ni) { 00300 if (ni != 8 || c != '.') break; 00301 i = 8; 00302 ni = 11; 00303 continue; 00304 } 00305 #ifdef _EXCVT 00306 if (c >= 0x80) /* To upper extended char (SBCS) */ 00307 c = cvt[c - 0x80]; 00308 #endif 00309 if (IsDBCS1(c) && i >= ni - 1) { /* DBC 1st byte? */ 00310 d = p[si++]; /* Get 2nd byte */ 00311 sfn[i++] = c; 00312 sfn[i++] = d; 00313 } else { /* Single byte code */ 00314 if (IsLower(c)) c -= 0x20; /* toupper */ 00315 sfn[i++] = c; 00316 } 00317 } 00318 *path = &p[si]; /* Rerurn pointer to the next segment */ 00319 00320 sfn[11] = (c <= ' ') ? 1 : 0; /* Set last segment flag if end of path */ 00321 00322 return FR_OK; 00323 } 00324 00325 00326 00327 00328 /*-----------------------------------------------------------------------*/ 00329 /* Get file information from directory entry */ 00330 /*-----------------------------------------------------------------------*/ 00331 #if _USE_DIR 00332 static 00333 void get_fileinfo ( /* No return code */ 00334 FATDIR *dj, /* Pointer to the directory object */ 00335 FILINFO *fno /* Pointer to store the file information */ 00336 ) { 00337 BYTE i, c, *dir; 00338 char *p; 00339 00340 00341 p = fno->fname; 00342 if (dj->sect) { 00343 dir = FatFs->buf; 00344 for (i = 0; i < 8; i++) { /* Copy file name body */ 00345 c = dir[i]; 00346 if (c == ' ') break; 00347 if (c == 0x05) c = 0xE5; 00348 *p++ = c; 00349 } 00350 if (dir[8] != ' ') { /* Copy file name extension */ 00351 *p++ = '.'; 00352 for (i = 8; i < 11; i++) { 00353 c = dir[i]; 00354 if (c == ' ') break; 00355 *p++ = c; 00356 } 00357 } 00358 fno->fattrib = dir[DIR_Attr]; /* Attribute */ 00359 fno->fsize = LD_DWORD(dir+DIR_FileSize); /* Size */ 00360 fno->fdate = LD_WORD(dir+DIR_WrtDate); /* Date */ 00361 fno->ftime = LD_WORD(dir+DIR_WrtTime); /* Time */ 00362 } 00363 *p = 0; 00364 } 00365 #endif /* _USE_DIR */ 00366 00367 00368 00369 /*-----------------------------------------------------------------------*/ 00370 /* Follow a file path */ 00371 /*-----------------------------------------------------------------------*/ 00372 00373 static 00374 FRESULT follow_path ( /* FR_OK(0): successful, !=0: error code */ 00375 FATDIR *dj, /* Directory object to return last directory and found object */ 00376 const char *path /* Full-path string to find a file or directory */ 00377 ) { 00378 FRESULT res; 00379 BYTE *dir; 00380 00381 00382 while (*path == ' ') path++; /* Skip leading spaces */ 00383 if (*path == '/') path++; /* Strip heading separator */ 00384 dj->sclust = 0; /* Set start directory (always root dir) */ 00385 00386 if ((BYTE)*path <= ' ') { /* Null path means the root directory */ 00387 res = dir_rewind(dj); 00388 FatFs->buf[0] = 0; 00389 00390 } else { /* Follow path */ 00391 for (;;) { 00392 res = create_name(dj, &path); /* Get a segment */ 00393 if (res != FR_OK) break; 00394 res = dir_find(dj); /* Find it */ 00395 if (res != FR_OK) { /* Could not find the object */ 00396 if (res == FR_NO_FILE && !*(dj->fn+11)) 00397 res = FR_NO_PATH; 00398 break; 00399 } 00400 if (*(dj->fn+11)) break; /* Last segment match. Function completed. */ 00401 dir = FatFs->buf; /* There is next segment. Follow the sub directory */ 00402 if (!(dir[DIR_Attr] & AM_DIR)) { /* Cannot follow because it is a file */ 00403 res = FR_NO_PATH; 00404 break; 00405 } 00406 dj->sclust = 00407 #if _FS_FAT32 00408 ((DWORD)LD_WORD(dir+DIR_FstClusHI) << 16) | 00409 #endif 00410 LD_WORD(dir+DIR_FstClusLO); 00411 } 00412 } 00413 00414 return res; 00415 } 00416 00417 00418 00419 00420 /*-----------------------------------------------------------------------*/ 00421 /* Check a sector if it is an FAT boot record */ 00422 /*-----------------------------------------------------------------------*/ 00423 00424 static 00425 __attribute__((section(".SD_Code"))) BYTE check_fs ( /* 0:The FAT boot record, 1:Valid boot record but not an FAT, 2:Not a boot record, 3:Error */ 00426 BYTE *buf, /* Working buffer */ 00427 DWORD sect /* Sector# (lba) to check if it is an FAT boot record or not */ 00428 ) { 00429 if (disk_readp(buf, sect, 510, 2)) /* Read the boot sector */ 00430 return 3; 00431 if (LD_WORD(buf) != 0xAA55) /* Check record signature */ 00432 return 2; 00433 00434 if (!disk_readp(buf, sect, BS_FilSysType, 2) && LD_WORD(buf) == 0x4146) /* Check FAT12/16 */ 00435 return 0; 00436 #if _FS_FAT32 00437 if (!disk_readp(buf, sect, BS_FilSysType32, 2) && LD_WORD(buf) == 0x4146) /* Check FAT32 */ 00438 return 0; 00439 #endif 00440 return 1; 00441 } 00442 00443 00444 00445 00446 /*-------------------------------------------------------------------------- 00447 00448 Public Functions 00449 00450 --------------------------------------------------------------------------*/ 00451 00452 00453 00454 /*-----------------------------------------------------------------------*/ 00455 /* Mount/Unmount a Locical Drive */ 00456 /*-----------------------------------------------------------------------*/ 00457 00458 __attribute__((section(".SD_Code"))) FRESULT pf_mount ( 00459 FATFS *fs /* Pointer to new file system object (NULL: Unmount) */ 00460 ) { 00461 BYTE fmt, buf[36]; 00462 DWORD bsect, fsize, tsect, mclst; 00463 00464 00465 FatFs = 0; 00466 if (!fs) return FR_OK; /* Unregister fs object */ 00467 00468 if (disk_initialize() & STA_NOINIT) /* Check if the drive is ready or not */ 00469 return FR_NOT_READY; 00470 00471 /* Search FAT partition on the drive */ 00472 bsect = 0; 00473 fmt = check_fs(buf, bsect); /* Check sector 0 as an SFD format */ 00474 if (fmt == 1) { /* Not an FAT boot record, it may be FDISK format */ 00475 /* Check a partition listed in top of the partition table */ 00476 if (disk_readp(buf, bsect, MBR_Table, 16)) { /* 1st partition entry */ 00477 fmt = 3; 00478 } else { 00479 if (buf[4]) { /* Is the partition existing? */ 00480 bsect = LD_DWORD(&buf[8]); /* Partition offset in LBA */ 00481 fmt = check_fs(buf, bsect); /* Check the partition */ 00482 } 00483 } 00484 } 00485 if (fmt == 3) return FR_DISK_ERR; 00486 if (fmt) return FR_NO_FILESYSTEM; /* No valid FAT patition is found */ 00487 00488 /* Initialize the file system object */ 00489 if (disk_readp(buf, bsect, 13, sizeof(buf))) return FR_DISK_ERR; 00490 00491 fsize = LD_WORD(buf+BPB_FATSz16-13); /* Number of sectors per FAT */ 00492 if (!fsize) fsize = LD_DWORD(buf+BPB_FATSz32-13); 00493 00494 fsize *= buf[BPB_NumFATs-13]; /* Number of sectors in FAT area */ 00495 fs->fatbase = bsect + LD_WORD(buf+BPB_RsvdSecCnt-13); /* FAT start sector (lba) */ 00496 fs->csize = buf[BPB_SecPerClus-13]; /* Number of sectors per cluster */ 00497 fs->n_rootdir = LD_WORD(buf+BPB_RootEntCnt-13); /* Nmuber of root directory entries */ 00498 tsect = LD_WORD(buf+BPB_TotSec16-13); /* Number of sectors on the file system */ 00499 if (!tsect) tsect = LD_DWORD(buf+BPB_TotSec32-13); 00500 mclst = (tsect /* Last cluster# + 1 */ 00501 - LD_WORD(buf+BPB_RsvdSecCnt-13) - fsize - fs->n_rootdir / 16 00502 ) / fs->csize + 2; 00503 fs->max_clust = (CLUST)mclst; 00504 00505 fmt = FS_FAT12; /* Determine the FAT sub type */ 00506 if (mclst >= 0xFF7) fmt = FS_FAT16; /* Number of clusters >= 0xFF5 */ 00507 if (mclst >= 0xFFF7) /* Number of clusters >= 0xFFF5 */ 00508 #if _FS_FAT32 00509 fmt = FS_FAT32; 00510 #else 00511 return FR_NO_FILESYSTEM; 00512 #endif 00513 00514 fs->fs_type = fmt; /* FAT sub-type */ 00515 #if _FS_FAT32 00516 if (fmt == FS_FAT32) 00517 fs->dirbase = LD_DWORD(buf+(BPB_RootClus-13)); /* Root directory start cluster */ 00518 else 00519 #endif 00520 fs->dirbase = fs->fatbase + fsize; /* Root directory start sector (lba) */ 00521 fs->database = fs->fatbase + fsize + fs->n_rootdir / 16; /* Data start sector (lba) */ 00522 00523 fs->flag = 0; 00524 FatFs = fs; 00525 00526 return FR_OK; 00527 } 00528 00529 00530 00531 00532 /*-----------------------------------------------------------------------*/ 00533 /* Open or Create a File */ 00534 /*-----------------------------------------------------------------------*/ 00535 00536 FRESULT pf_open ( 00537 const char *path /* Pointer to the file name */ 00538 ) { 00539 FRESULT res; 00540 FATDIR dj; 00541 BYTE sp[12], dir[32]; 00542 FATFS *fs = FatFs; 00543 00544 00545 if (!fs) /* Check file system */ 00546 return FR_NOT_ENABLED; 00547 00548 fs->flag = 0; 00549 fs->buf = dir; 00550 dj.fn = sp; 00551 res = follow_path(&dj, path); /* Follow the file path */ 00552 if (res != FR_OK) return res; /* Follow failed */ 00553 if (!dir[0] || (dir[DIR_Attr] & AM_DIR)) /* It is a directory */ 00554 return FR_NO_FILE; 00555 00556 fs->org_clust = /* File start cluster */ 00557 #if _FS_FAT32 00558 ((DWORD)LD_WORD(dir+DIR_FstClusHI) << 16) | 00559 #endif 00560 LD_WORD(dir+DIR_FstClusLO); 00561 fs->fsize = LD_DWORD(dir+DIR_FileSize); /* File size */ 00562 fs->fptr = 0; /* File pointer */ 00563 fs->flag = FA_OPENED; 00564 00565 return FR_OK; 00566 } 00567 00568 00569 00570 00571 /*-----------------------------------------------------------------------*/ 00572 /* Read File */ 00573 /*-----------------------------------------------------------------------*/ 00574 #if _USE_READ 00575 00576 FRESULT pf_read ( 00577 void* buff, /* Pointer to the read buffer (NULL:Forward data to the stream)*/ 00578 WORD btr, /* Number of bytes to read */ 00579 WORD* br /* Pointer to number of bytes read */ 00580 ) { 00581 DRESULT dr; 00582 CLUST clst; 00583 DWORD sect, remain; 00584 BYTE *rbuff = (BYTE *)buff; 00585 WORD rcnt; 00586 FATFS *fs = FatFs; 00587 00588 00589 *br = 0; 00590 if (!fs) return FR_NOT_ENABLED; /* Check file system */ 00591 if (!(fs->flag & FA_OPENED)) /* Check if opened */ 00592 return FR_NOT_OPENED; 00593 00594 remain = fs->fsize - fs->fptr; 00595 if (btr > remain) btr = (WORD)remain; /* Truncate btr by remaining bytes */ 00596 00597 while (btr) { /* Repeat until all data transferred */ 00598 if ((fs->fptr % 512) == 0) { /* On the sector boundary? */ 00599 if ((fs->fptr / 512 % fs->csize) == 0) { /* On the cluster boundary? */ 00600 clst = (fs->fptr == 0) ? /* On the top of the file? */ 00601 fs->org_clust : get_fat(fs->curr_clust); 00602 if (clst <= 1) goto fr_abort; 00603 fs->curr_clust = clst; /* Update current cluster */ 00604 fs->csect = 0; /* Reset sector offset in the cluster */ 00605 } 00606 sect = clust2sect(fs->curr_clust); /* Get current sector */ 00607 if (!sect) goto fr_abort; 00608 fs->dsect = sect + fs->csect++; 00609 } 00610 rcnt = 512 - ((WORD)fs->fptr % 512); /* Get partial sector data from sector buffer */ 00611 if (rcnt > btr) rcnt = btr; 00612 dr = disk_readp(!buff ? 0 : rbuff, fs->dsect, (WORD)(fs->fptr % 512), rcnt); 00613 if (dr) goto fr_abort; 00614 fs->fptr += rcnt; 00615 rbuff += rcnt; /* Update pointers and counters */ 00616 btr -= rcnt; 00617 *br += rcnt; 00618 } 00619 00620 return FR_OK; 00621 00622 fr_abort: 00623 fs->flag = 0; 00624 return FR_DISK_ERR; 00625 } 00626 #endif 00627 00628 00629 00630 /*-----------------------------------------------------------------------*/ 00631 /* Write File */ 00632 /*-----------------------------------------------------------------------*/ 00633 #if _USE_WRITE 00634 00635 FRESULT pf_write ( 00636 const void* buff, /* Pointer to the data to be written */ 00637 WORD btw, /* Number of bytes to write (0:Finalize the current write operation) */ 00638 WORD* bw /* Pointer to number of bytes written */ 00639 ) { 00640 CLUST clst; 00641 DWORD sect, remain; 00642 const BYTE *p = (const BYTE *)buff; 00643 WORD wcnt; 00644 FATFS *fs = FatFs; 00645 00646 00647 *bw = 0; 00648 if (!fs) return FR_NOT_ENABLED; /* Check file system */ 00649 if (!(fs->flag & FA_OPENED)) /* Check if opened */ 00650 return FR_NOT_OPENED; 00651 00652 if (!btw) { /* Finalize request */ 00653 if ((fs->flag & FA__WIP) && disk_writep(0, 0)) goto fw_abort; 00654 fs->flag &= ~FA__WIP; 00655 return FR_OK; 00656 } else { /* Write data request */ 00657 if (!(fs->flag & FA__WIP)) /* Round down fptr to the sector boundary */ 00658 fs->fptr &= 0xFFFFFE00; 00659 } 00660 remain = fs->fsize - fs->fptr; 00661 if (btw > remain) btw = (WORD)remain; /* Truncate btw by remaining bytes */ 00662 00663 while (btw) { /* Repeat until all data transferred */ 00664 if (((WORD)fs->fptr % 512) == 0) { /* On the sector boundary? */ 00665 if ((fs->fptr / 512 % fs->csize) == 0) { /* On the cluster boundary? */ 00666 clst = (fs->fptr == 0) ? /* On the top of the file? */ 00667 fs->org_clust : get_fat(fs->curr_clust); 00668 if (clst <= 1) goto fw_abort; 00669 fs->curr_clust = clst; /* Update current cluster */ 00670 fs->csect = 0; /* Reset sector offset in the cluster */ 00671 } 00672 sect = clust2sect(fs->curr_clust); /* Get current sector */ 00673 if (!sect) goto fw_abort; 00674 fs->dsect = sect + fs->csect++; 00675 if (disk_writep(0, fs->dsect)) goto fw_abort; /* Initiate a sector write operation */ 00676 fs->flag |= FA__WIP; 00677 } 00678 wcnt = 512 - ((WORD)fs->fptr % 512); /* Number of bytes to write to the sector */ 00679 if (wcnt > btw) wcnt = btw; 00680 if (disk_writep(p, wcnt)) goto fw_abort; /* Send data to the sector */ 00681 fs->fptr += wcnt; 00682 p += wcnt; /* Update pointers and counters */ 00683 btw -= wcnt; 00684 *bw += wcnt; 00685 if (((WORD)fs->fptr % 512) == 0) { 00686 if (disk_writep(0, 0)) goto fw_abort; /* Finalize the currtent secter write operation */ 00687 fs->flag &= ~FA__WIP; 00688 } 00689 } 00690 00691 return FR_OK; 00692 00693 fw_abort: 00694 fs->flag = 0; 00695 return FR_DISK_ERR; 00696 } 00697 #endif 00698 00699 00700 00701 /*-----------------------------------------------------------------------*/ 00702 /* Seek File R/W Pointer */ 00703 /*-----------------------------------------------------------------------*/ 00704 #if _USE_LSEEK 00705 00706 FRESULT pf_lseek ( 00707 DWORD ofs /* File pointer from top of file */ 00708 ) { 00709 CLUST clst; 00710 DWORD bcs, sect, ifptr; 00711 FATFS *fs = FatFs; 00712 00713 00714 if (!fs) return FR_NOT_ENABLED; /* Check file system */ 00715 if (!(fs->flag & FA_OPENED)) /* Check if opened */ 00716 return FR_NOT_OPENED; 00717 00718 if (ofs > fs->fsize) ofs = fs->fsize; /* Clip offset with the file size */ 00719 ifptr = fs->fptr; 00720 fs->fptr = 0; 00721 if (ofs > 0) { 00722 bcs = (DWORD)fs->csize * 512; /* Cluster size (byte) */ 00723 if (ifptr > 0 && 00724 (ofs - 1) / bcs >= (ifptr - 1) / bcs) { /* When seek to same or following cluster, */ 00725 fs->fptr = (ifptr - 1) & ~(bcs - 1); /* start from the current cluster */ 00726 ofs -= fs->fptr; 00727 clst = fs->curr_clust; 00728 } else { /* When seek to back cluster, */ 00729 clst = fs->org_clust; /* start from the first cluster */ 00730 fs->curr_clust = clst; 00731 } 00732 while (ofs > bcs) { /* Cluster following loop */ 00733 clst = get_fat(clst); /* Follow cluster chain */ 00734 if (clst <= 1 || clst >= fs->max_clust) goto fe_abort; 00735 fs->curr_clust = clst; 00736 fs->fptr += bcs; 00737 ofs -= bcs; 00738 } 00739 fs->fptr += ofs; 00740 sect = clust2sect(clst); /* Current sector */ 00741 if (!sect) goto fe_abort; 00742 fs->csect = (BYTE)(ofs / 512); /* Sector offset in the cluster */ 00743 if (ofs % 512) 00744 fs->dsect = sect + fs->csect++; 00745 } 00746 00747 return FR_OK; 00748 00749 fe_abort: 00750 fs->flag = 0; 00751 return FR_DISK_ERR; 00752 } 00753 #endif 00754 00755 00756 00757 /*-----------------------------------------------------------------------*/ 00758 /* Create a Directroy Object */ 00759 /*-----------------------------------------------------------------------*/ 00760 #if _USE_DIR 00761 00762 FRESULT pf_opendir ( 00763 FATDIR *dj, /* Pointer to directory object to create */ 00764 const char *path /* Pointer to the directory path */ 00765 ) { 00766 FRESULT res; 00767 BYTE sp[12], dir[32]; 00768 FATFS *fs = FatFs; 00769 00770 00771 if (!fs) { /* Check file system */ 00772 res = FR_NOT_ENABLED; 00773 } else { 00774 fs->buf = dir; 00775 dj->fn = sp; 00776 res = follow_path(dj, path); /* Follow the path to the directory */ 00777 if (res == FR_OK) { /* Follow completed */ 00778 if (dir[0]) { /* It is not the root dir */ 00779 if (dir[DIR_Attr] & AM_DIR) { /* The object is a directory */ 00780 dj->sclust = 00781 #if _FS_FAT32 00782 ((DWORD)LD_WORD(dir+DIR_FstClusHI) << 16) | 00783 #endif 00784 LD_WORD(dir+DIR_FstClusLO); 00785 } else { /* The object is not a directory */ 00786 res = FR_NO_PATH; 00787 } 00788 } 00789 if (res == FR_OK) 00790 res = dir_rewind(dj); /* Rewind dir */ 00791 } 00792 if (res == FR_NO_FILE) res = FR_NO_PATH; 00793 } 00794 00795 return res; 00796 } 00797 00798 00799 00800 00801 /*-----------------------------------------------------------------------*/ 00802 /* Read Directory Entry in Sequense */ 00803 /*-----------------------------------------------------------------------*/ 00804 00805 FRESULT pf_readdir ( 00806 FATDIR *dj, /* Pointer to the open directory object */ 00807 FILINFO *fno /* Pointer to file information to return */ 00808 ) { 00809 FRESULT res; 00810 BYTE sp[12], dir[32]; 00811 FATFS *fs = FatFs; 00812 00813 00814 if (!fs) { /* Check file system */ 00815 res = FR_NOT_ENABLED; 00816 } else { 00817 fs->buf = dir; 00818 dj->fn = sp; 00819 if (!fno) { 00820 res = dir_rewind(dj); 00821 } else { 00822 res = dir_read(dj); 00823 if (res == FR_NO_FILE) { 00824 dj->sect = 0; 00825 res = FR_OK; 00826 } 00827 if (res == FR_OK) { /* A valid entry is found */ 00828 get_fileinfo(dj, fno); /* Get the object information */ 00829 res = dir_next(dj); /* Increment index for next */ 00830 if (res == FR_NO_FILE) { 00831 dj->sect = 0; 00832 res = FR_OK; 00833 } 00834 } 00835 } 00836 } 00837 00838 return res; 00839 } 00840 00841 #endif /* _USE_DIR */ 00842 00843 } // namespace PFFS 00844 00845
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