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467 2 if (!move_window(scan->sect)) return NULL;
468 2 dptr = &(fs->win[(scan->index & 15) * 32]); /* Pointer to the directory entry */
469 2 c = *dptr;
470 2 if ((c == 0) || (c == 0xE5)) return dptr; /* Found an empty entry! */
471 2 } while (next_dir_entry(scan)); /* Next directory pointer */
472 1 /* Reached to end of the directory table */
473 1
474 1 /* Abort when static table or could not stretch dynamic table */
475 1 if ((!clust) || !(clust = create_chain(scan->clust))) return NULL;
476 1 if (!move_window(0)) return 0;
477 1
478 1 fs->winsect = sector = clust2sect(clust); /* Cleanup the expanded table */
479 1 memset(fs->win, 0, 512);
480 1 for (n = fs->sects_clust; n; n--) {
481 2 if (disk_write(fs->win, sector, 1) != RES_OK) return NULL;
482 2 sector++;
483 2 }
484 1 fs->winflag = 1;
485 1 return fs->win;
486 1 }
487 #endif /* _FS_READONLY */
488
C51 COMPILER V7.02b TFF 03/24/2008 15:52:29 PAGE 9
489
490
491 /*-----------------------------------------*/
492 /* Make Sure that the File System is Valid */
493
494 static
495 FRESULT check_mounted ()
496 {
497 1 FATFS *fs = FatFs;
498 1
499 1
500 1 if (!fs) return FR_NOT_ENABLED; /* Has the FatFs been enabled? */
501 1
502 1 if (disk_status() & STA_NOINIT) { /* The drive has not been initialized */
503 2 if (fs->files) /* Drive was uninitialized with any file left opend */
504 2 return FR_INCORRECT_DISK_CHANGE;
505 2 else
506 2 return f_mountdrv(); /* Initialize file system and return resulut */
507 2 } else { /* The drive has been initialized */
508 2 if (!fs->fs_type) /* But the file system has not been initialized */
509 2 return f_mountdrv(); /* Initialize file system and return resulut */
510 2 }
511 1 return FR_OK; /* File system is valid */
512 1 }
513
514
515
516
517
518 /*--------------------------------------------------------------------------*/
519 /* Public Funciotns */
520 /*--------------------------------------------------------------------------*/
521
522
523 /*--------------------------------------------------------*/
524 /* Load File System Information and Initialize the Module */
525
526 FRESULT f_mountdrv ()
527 {
528 1 BYTE fat;
529 1 DWORD sect, fatend, maxsect;
530 1 FATFS *fs = &fatfsentity;
531 1 FatFs = fs;
532 1
533 1 if (!fs) return FR_NOT_ENABLED;
534 1
535 1 /* Initialize file system object */
536 1 memset(fs, 0, sizeof(FATFS));
537 1
538 1 /* Initialize disk drive */
539 1 //if (disk_initialize() & STA_NOINIT) return FR_NOT_READY;
540 1
541 1 /* Search FAT partition */
542 1 fat = check_fs(sect = 0); /* Check sector 0 as an SFD format */
543 1 if (!fat) { /* Not a FAT boot record, it will be an FDISK format */
544 2 /* Check first pri-partition listed in the partition table */
545 2 if (fs->win[0x1C2]) { /* Is a partition existing? */
546 3 sect = LD_DWORD(&(fs->win[0x1C6])); /* Partition offset in LBA */
547 3 fat = check_fs(sect); /* Check the partition */
548 3 }
549 2 }
550 1 if (!fat) return FR_NO_FILESYSTEM; /* No FAT patition */
C51 COMPILER V7.02b TFF 03/24/2008 15:52:29 PAGE 10
551 1
552 1 /* Initialize file system object */
553 1 fs->fs_type = fat; /* FAT type */
554 1 fs->sects_fat = LD_WORD(&(fs->win[0x16])); /* Sectors per FAT */
555 1 fs->sects_clust = fs->win[0x0D]; /* Sectors per cluster */
556 1 fs->n_fats = fs->win[0x10]; /* Number of FAT copies */
557 1 fs->fatbase = sect + LD_WORD(&(fs->win[0x0E])); /* FAT start sector (physical) */
558 1 fs->n_rootdir = LD_WORD(&(fs->win[0x11])); /* Nmuber of root directory entries */
559 1
560 1 fatend = fs->sects_fat * fs->n_fats + fs->fatbase;
561 1 fs->dirbase = fatend; /* Directory start sector (physical) */
562 1 fs->database = fs->n_rootdir / 16 + fatend; /* Data start sector (physical) */
563 1
564 1 maxsect = LD_DWORD(&(fs->win[0x20])); /* Calculate maximum cluster number */
565 1 if (!maxsect) maxsect = LD_WORD(&(fs->win[0x13]));
566 1 fs->max_clust = (maxsect - fs->database + sect) / fs->sects_clust + 2;
567 1
568 1 fs->files = 0;
569 1 return FR_OK;
570 1 }
571
572
573 /*-----------------------------*/
574 /* Get Number of Free Clusters */
575 #if 0
FRESULT f_getfree (
DWORD *nclust /* Pointer to the double word to return number of free clusters */
)
{
DWORD n, sect;
WORD clust;
BYTE f, *p;
FRESULT res;
FATFS *fs = FatFs;
if ((res = check_mounted()) != FR_OK) return res;
/* Count number of free clusters */
n = 0;
if (fs->fs_type == FS_FAT12) {
clust = 2;
do {
if (get_cluster(clust) == 0) n++;
} while (++clust < fs->max_clust);
} else {
clust = fs->max_clust;
sect = fs->fatbase;
f = 0; p = 0;
do {
if (!f) {
if (!move_window(sect++)) return FR_RW_ERROR;
p = fs->win;
}
if (LD_WORD(p) == 0) n++;
p += 2; f += 1;
} while (--clust);
}
*nclust = n;
return FR_OK;
}
C51 COMPILER V7.02b TFF 03/24/2008 15:52:29 PAGE 11
#endif
615
616 /*---------------------*/
617 /* Open or Create File */
618
619 FRESULT f_open (
620 FIL *fp, /* Pointer to the buffer of new file object to create */
621 const char *path, /* Pointer to the file path */
622 BYTE mode /* Access mode and file open mode flags */
623 )
624 {
625 1 FRESULT res;
626 1 BYTE *dir;
627 1 DIR dirscan;
628 1 char fn[8+3+1];
629 1 FATFS *fs = FatFs;
630 1
631 1
632 1 if ((res = check_mounted()) != FR_OK) return res;
633 1 #ifndef _FS_READONLY
634 1 if ((mode & (FA_WRITE|FA_CREATE_ALWAYS|FA_OPEN_ALWAYS)) && (disk_status() & STA_PROTECT))
635 1 return FR_WRITE_PROTECTED;
636 1 #endif
637 1
638 1 res = trace_path(&dirscan, fn, path, &dir); /* Trace the file path */
639 1
640 1 #ifndef _FS_READONLY
641 1 /* Create or Open a File */
642 1 if (mode & (FA_CREATE_ALWAYS|FA_OPEN_ALWAYS)) {
643 2 DWORD dw;
644 2 if (res != FR_OK) { /* No file, create new */
645 3 mode |= FA_CREATE_ALWAYS;
646 3 //if (res != FR_NO_FILE) return res;
647 3 dir = reserve_direntry(&dirscan); /* Reserve a directory entry */
648 3 if (dir == NULL) return FR_DENIED;
649 3 memcpy(dir, fn, 8+3); /* Initialize the new entry */
650 3 *(dir+12) = fn[11];
651 3 memset(dir+13, 0, 32-13);
652 3 } else { /* File already exists */
653 3 if ((dir == NULL) || (*(dir+11) & (AM_RDO|AM_DIR))) /* Could not overwrite (R/O or DIR) */
654 3 return FR_DENIED;
655 3 if (mode & FA_CREATE_ALWAYS) { /* Resize it to zero */
656 4 dw = fs->winsect; /* Remove the cluster chain */
657 4 if (!remove_chain(LD_WORD(dir+26)) || !move_window(dw) )
658 4 return FR_RW_ERROR;
659 4 ST_WORD(dir+26, 0); /* cluster = 0 */
660 4 ST_DWORD(dir+28, 0); /* size = 0 */
661 4 }
662 3 }
663 2 if (mode & FA_CREATE_ALWAYS) {
664 3 *(dir+11) = AM_ARC;
665 3 // dw = get_fattime();
666 3 // ST_DWORD(dir+14, dw); /* Created time */
667 3 // ST_DWORD(dir+22, dw); /* Updated time */
668 3 fs->winflag = 1;
669 3 }
670 2 }
671 1 /* Open a File */
672 1 else {
673 2 #endif /* _FS_READONLY */
674 2 if (res != FR_OK) return res; /* Trace failed */
C51 COMPILER V7.02b TFF 03/24/2008 15:52:29 PAGE 12
675 2 if ((dir == NULL) || (*(dir+11) & AM_DIR)) /* It is a directory */
676 2 return FR_NO_FILE;
677 2 #ifndef _FS_READONLY
678 2 if ((mode & FA_WRITE) && (*(dir+11) & AM_RDO)) /* R/O violation */
679 2 return FR_DENIED;
680 2 }
681 1 #endif
682 1
683 1 #ifdef _FS_READONLY
fp->flag = mode & FA_READ;
#else
686 1 fp->flag = mode & (FA_WRITE|FA_READ);
687 1 fp->dir_sect = fs->winsect; /* Pointer to the directory entry */
688 1 fp->dir_ptr = dir;
689 1 #endif
690 1 fp->org_clust = LD_WORD(dir+26); /* File start cluster */
691 1 fp->fsize = LD_DWORD(dir+28); /* File size */
692 1 fp->fptr = 0; /* File ptr */
693 1 fp->sect_clust = 1; /* Sector counter */
694 1 fs->files++;
695 1 return FR_OK;
696 1 }
697
698
699
700 /*-----------*/
701 /* Read File */
702
703 FRESULT f_read (
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