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/*----------------------------------------------------------------------------/
/  FatFs - FAT file system module  R0.06                     (C)ChaN, 2008
/-----------------------------------------------------------------------------/
/ The FatFs module is an experimenal project to implement FAT file system to
/ cheap microcontrollers. This is a free software and is opened for education,
/ research and development under license policy of following trems.
/
/  Copyright (C) 2008, ChaN, all right reserved.
/
/ * The FatFs module is a free software and there is no warranty.
/ * You can use, modify and/or redistribute it for personal, non-profit or
/   commercial use without restriction under your responsibility.
/ * Redistributions of source code must retain the above copyright notice.
/
/-----------------------------------------------------------------------------/
/ Feb 26,'06 R0.00  Prototype.
/
/ Apr 29,'06 R0.01  First stable version.
/
/ Jun 01,'06 R0.02  Added FAT12 support.
/                   Removed unbuffered mode.
/                   Fixed a problem on small (<32M) patition.
/ Jun 10,'06 R0.02a Added a configuration option (_FS_MINIMUM).
/
/ Sep 22,'06 R0.03  Added f_rename().
/                   Changed option _FS_MINIMUM to _FS_MINIMIZE.
/ Dec 11,'06 R0.03a Improved cluster scan algolithm to write files fast.
/                   Fixed f_mkdir() creates incorrect directory on FAT32.
/
/ Feb 04,'07 R0.04  Supported multiple drive system.
/                   Changed some interfaces for multiple drive system.
/                   Changed f_mountdrv() to f_mount().
/                   Added f_mkfs().
/ Apr 01,'07 R0.04a Supported multiple partitions on a plysical drive.
/                   Added a capability of extending file size to f_lseek().
/                   Added minimization level 3.
/                   Fixed an endian sensitive code in f_mkfs().
/ May 05,'07 R0.04b Added a configuration option _USE_NTFLAG.
/                   Added FSInfo support.
/                   Fixed DBCS name can result FR_INVALID_NAME.
/                   Fixed short seek (<= csize) collapses the file object.
/
/ Aug 25,'07 R0.05  Changed arguments of f_read(), f_write() and f_mkfs().
/                   Fixed f_mkfs() on FAT32 creates incorrect FSInfo.
/                   Fixed f_mkdir() on FAT32 creates incorrect directory.
/ Feb 03,'08 R0.05a Added f_truncate() and f_utime().
/                   Fixed off by one error at FAT sub-type determination.
/                   Fixed btr in f_read() can be mistruncated.
/                   Fixed cached sector is not flushed when create and close
/                   without write.
/
/ Apr 01,'08 R0.06  Added fputc(), fputs(), fprintf() and fgets().
/                   Improved performance of f_lseek() on moving to the same
/                   or following cluster.
/---------------------------------------------------------------------------*/

#include <string.h>
#include "ff.h"                 /* FatFs declarations */
#include "diskio.h"             /* Include file for user provided disk functions */


/*--------------------------------------------------------------------------

   Module Private Functions

---------------------------------------------------------------------------*/

static
FATFS *FatFs[_DRIVES];  /* Pointer to the file system objects (logical drives) */
static
WORD fsid;                              /* File system mount ID */



/*-----------------------------------------------------------------------*/
/* Change window offset                                                  */
/*-----------------------------------------------------------------------*/

static
BOOL move_window (      /* TRUE: successful, FALSE: failed */
        FATFS *fs,              /* File system object */
        DWORD sector    /* Sector number to make apperance in the fs->win[] */
)                                       /* Move to zero only writes back dirty window */
{
        DWORD wsect;


        wsect = fs->winsect;
        if (wsect != sector) {  /* Changed current window */
#if !_FS_READONLY
                BYTE n;
                if (fs->winflag) {      /* Write back dirty window if needed */
                        if (disk_write(fs->drive, fs->win, wsect, 1) != RES_OK)
                                return FALSE;
                        fs->winflag = 0;
                        if (wsect < (fs->fatbase + fs->sects_fat)) {    /* In FAT area */
                                for (n = fs->n_fats; n >= 2; n--) {     /* Refrect the change to FAT copy */
                                        wsect += fs->sects_fat;
                                        disk_write(fs->drive, fs->win, wsect, 1);
                                }
                        }
                }
#endif
                if (sector) {
                        if (disk_read(fs->drive, fs->win, sector, 1) != RES_OK)
                                return FALSE;
                        fs->winsect = sector;
                }
        }
        return TRUE;
}




/*-----------------------------------------------------------------------*/
/* Clean-up cached data                                                  */
/*-----------------------------------------------------------------------*/

#if !_FS_READONLY
static
FRESULT sync (  /* FR_OK: successful, FR_RW_ERROR: failed */
        FATFS *fs       /* File system object */
)
{
        fs->winflag = 1;
        if (!move_window(fs, 0)) return FR_RW_ERROR;
#if _USE_FSINFO
        /* Update FSInfo sector if needed */
        if (fs->fs_type == FS_FAT32 && fs->fsi_flag) {
                fs->winsect = 0;
                memset(fs->win, 0, 512);
                ST_WORD(&fs->win[BS_55AA], 0xAA55);
                ST_DWORD(&fs->win[FSI_LeadSig], 0x41615252);
                ST_DWORD(&fs->win[FSI_StrucSig], 0x61417272);
                ST_DWORD(&fs->win[FSI_Free_Count], fs->free_clust);
                ST_DWORD(&fs->win[FSI_Nxt_Free], fs->last_clust);
                disk_write(fs->drive, fs->win, fs->fsi_sector, 1);
                fs->fsi_flag = 0;
        }
#endif
        /* Make sure that no pending write process in the physical drive */
        if (disk_ioctl(fs->drive, CTRL_SYNC, NULL) != RES_OK)
                return FR_RW_ERROR;
        return FR_OK;
}
#endif




/*-----------------------------------------------------------------------*/
/* Get a cluster status                                                  */
/*-----------------------------------------------------------------------*/

static
DWORD get_cluster (     /* 0,>=2: successful, 1: failed */
        FATFS *fs,              /* File system object */
        DWORD clust             /* Cluster# to get the link information */
)
{
        WORD wc, bc;
        DWORD fatsect;


        if (clust >= 2 && clust < fs->max_clust) {              /* Is it a valid cluster#? */
                fatsect = fs->fatbase;
                switch (fs->fs_type) {
                case FS_FAT12 :
                        bc = (WORD)clust * 3 / 2;
                        if (!move_window(fs, fatsect + (bc / SS(fs)))) break;
                        wc = fs->win[bc & (SS(fs) - 1)]; bc++;
                        if (!move_window(fs, fatsect + (bc / SS(fs)))) break;
                        wc |= (WORD)fs->win[bc & (SS(fs) - 1)] << 8;
                        return (clust & 1) ? (wc >> 4) : (wc & 0xFFF);

                case FS_FAT16 :
                        if (!move_window(fs, fatsect + (clust / (SS(fs) / 2)))) break;
                        return LD_WORD(&fs->win[((WORD)clust * 2) & (SS(fs) - 1)]);

                case FS_FAT32 :
                        if (!move_window(fs, fatsect + (clust / (SS(fs) / 4)))) break;
                        return LD_DWORD(&fs->win[((WORD)clust * 4) & (SS(fs) - 1)]) & 0x0FFFFFFF;
                }
        }

        return 1;       /* Out of cluster range, or an error occured */
}




/*-----------------------------------------------------------------------*/
/* Change a cluster status                                               */
/*-----------------------------------------------------------------------*/

#if !_FS_READONLY
static
BOOL put_cluster (      /* TRUE: successful, FALSE: failed */
        FATFS *fs,              /* File system object */
        DWORD clust,    /* Cluster# to change (must be 2 to fs->max_clust-1) */
        DWORD val               /* New value to mark the cluster */
)
{
        WORD bc;
        BYTE *p;
        DWORD fatsect;


        fatsect = fs->fatbase;
        switch (fs->fs_type) {
        case FS_FAT12 :
                bc = (WORD)clust * 3 / 2;
                if (!move_window(fs, fatsect + (bc / SS(fs)))) return FALSE;
                p = &fs->win[bc & (SS(fs) - 1)];
                *p = (clust & 1) ? ((*p & 0x0F) | ((BYTE)val << 4)) : (BYTE)val;
                bc++;
                fs->winflag = 1;
                if (!move_window(fs, fatsect + (bc / SS(fs)))) return FALSE;
                p = &fs->win[bc & (SS(fs) - 1)];
                *p = (clust & 1) ? (BYTE)(val >> 4) : ((*p & 0xF0) | ((BYTE)(val >> 8) & 0x0F));
                break;

        case FS_FAT16 :
                if (!move_window(fs, fatsect + (clust / (SS(fs) / 2)))) return FALSE;
                ST_WORD(&fs->win[((WORD)clust * 2) & (SS(fs) - 1)], (WORD)val);
                break;

        case FS_FAT32 :
                if (!move_window(fs, fatsect + (clust / (SS(fs) / 4)))) return FALSE;
                ST_DWORD(&fs->win[((WORD)clust * 4) & (SS(fs) - 1)], val);
                break;

        default :
                return FALSE;
        }
        fs->winflag = 1;
        return TRUE;
}
#endif /* !_FS_READONLY */




/*-----------------------------------------------------------------------*/
/* Remove a cluster chain                                                */
/*-----------------------------------------------------------------------*/

#if !_FS_READONLY
static
BOOL remove_chain (     /* TRUE: successful, FALSE: failed */
        FATFS *fs,              /* File system object */
        DWORD clust             /* Cluster# to remove chain from */
)
{
        DWORD nxt;


        while (clust >= 2 && clust < fs->max_clust) {
                nxt = get_cluster(fs, clust);
                if (nxt == 1) return FALSE;
                if (!put_cluster(fs, clust, 0)) return FALSE;
                if (fs->free_clust != 0xFFFFFFFF) {
                        fs->free_clust++;
#if _USE_FSINFO
                        fs->fsi_flag = 1;
#endif
                }
                clust = nxt;
        }
        return TRUE;
}
#endif




/*-----------------------------------------------------------------------*/
/* Stretch or create a cluster chain                                     */
/*-----------------------------------------------------------------------*/

#if !_FS_READONLY
static
DWORD create_chain (    /* 0: No free cluster, 1: Error, >=2: New cluster number */
        FATFS *fs,                      /* File system object */
        DWORD clust                     /* Cluster# to stretch, 0 means create new */
)
{
        DWORD cstat, ncl, scl, mcl = fs->max_clust;


        if (clust == 0) {               /* Create new chain */
                scl = fs->last_clust;                   /* Get suggested start point */
                if (scl == 0 || scl >= mcl) scl = 1;
        }
        else {                                  /* Stretch existing chain */
                cstat = get_cluster(fs, clust); /* Check the cluster status */
                if (cstat < 2) return 1;                /* It is an invalid cluster */
                if (cstat < mcl) return cstat;  /* It is already followed by next cluster */
                scl = clust;
        }

        ncl = scl;                              /* Start cluster */
        for (;;) {
                ncl++;                                                  /* Next cluster */
                if (ncl >= mcl) {                               /* Wrap around */
                        ncl = 2;
                        if (ncl > scl) return 0;        /* No free custer */
                }
                cstat = get_cluster(fs, ncl);   /* Get the cluster status */
                if (cstat == 0) break;                  /* Found a free cluster */
                if (cstat == 1) return 1;               /* Any error occured */
                if (ncl == scl) return 0;               /* No free custer */
        }

        if (!put_cluster(fs, ncl, 0x0FFFFFFF)) return 1;                        /* Mark the new cluster "in use" */
        if (clust != 0 && !put_cluster(fs, clust, ncl)) return 1;       /* Link it to previous one if needed */

        fs->last_clust = ncl;                           /* Update fsinfo */
        if (fs->free_clust != 0xFFFFFFFF) {
                fs->free_clust--;
#if _USE_FSINFO
                fs->fsi_flag = 1;
#endif
        }

        return ncl;             /* Return new cluster number */
}
#endif /* !_FS_READONLY */




/*-----------------------------------------------------------------------*/
/* Get sector# from cluster#                                             */
/*-----------------------------------------------------------------------*/

static
DWORD clust2sect (      /* !=0: sector number, 0: failed - invalid cluster# */
        FATFS *fs,              /* File system object */
        DWORD clust             /* Cluster# to be converted */
)
{
        clust -= 2;
        if (clust >= (fs->max_clust - 2)) return 0;             /* Invalid cluster# */
        return clust * fs->csize + fs->database;
}




/*-----------------------------------------------------------------------*/
/* Move directory pointer to next                                        */
/*-----------------------------------------------------------------------*/

static
BOOL next_dir_entry (   /* TRUE: successful, FALSE: could not move next */
        DIR *dj                         /* Pointer to directory object */
)
{
        DWORD clust;
        WORD idx;


        idx = dj->index + 1;
        if ((idx & ((SS(dj->fs) - 1) / 32)) == 0) {             /* Table sector changed? */
                dj->sect++;                             /* Next sector */
                if (dj->clust == 0) {   /* In static table */
                        if (idx >= dj->fs->n_rootdir) return FALSE;     /* Reached to end of table */
                } else {                                        /* In dynamic table */
                        if (((idx / (SS(dj->fs) / 32)) & (dj->fs->csize - 1)) == 0) {   /* Cluster changed? */
                                clust = get_cluster(dj->fs, dj->clust);                 /* Get next cluster */
                                if (clust < 2 || clust >= dj->fs->max_clust)    /* Reached to end of table */
                                        return FALSE;
                                dj->clust = clust;                              /* Initialize for new cluster */
                                dj->sect = clust2sect(dj->fs, clust);
                        }
                }
        }
        dj->index = idx;        /* Lower several bits of dj->index indicates offset in dj->sect */
        return TRUE;
}




/*-----------------------------------------------------------------------*/
/* Get file status from directory entry                                  */
/*-----------------------------------------------------------------------*/

#if _FS_MINIMIZE <= 1
static
void get_fileinfo (     /* No return code */
        FILINFO *finfo, /* Ptr to store the file information */
        const BYTE *dir /* Ptr to the directory entry */
)
{
        BYTE n, c, a;
        char *p;


        p = &finfo->fname[0];
        a = _USE_NTFLAG ? dir[DIR_NTres] : 0;           /* NT flag */
        for (n = 0; n < 8; n++) {       /* Convert file name (body) */
                c = dir[n];
                if (c == ' ') break;
                if (c == 0x05) c = 0xE5;
                if (a & 0x08 && c >= 'A' && c <= 'Z') c += 0x20;
                *p++ = c;
        }
        if (dir[8] != ' ') {            /* Convert file name (extension) */
                *p++ = '.';
                for (n = 8; n < 11; n++) {
                        c = dir[n];
                        if (c == ' ') break;
                        if (a & 0x10 && c >= 'A' && c <= 'Z') c += 0x20;
                        *p++ = c;
                }
        }
        *p = '\0';

        finfo->fattrib = dir[DIR_Attr];                                 /* Attribute */
        finfo->fsize = LD_DWORD(&dir[DIR_FileSize]);    /* Size */
        finfo->fdate = LD_WORD(&dir[DIR_WrtDate]);              /* Date */
        finfo->ftime = LD_WORD(&dir[DIR_WrtTime]);              /* Time */
}
#endif /* _FS_MINIMIZE <= 1 */




/*-----------------------------------------------------------------------*/
/* Pick a paragraph and create the name in format of directory entry     */
/*-----------------------------------------------------------------------*/

static
char make_dirfile (             /* 1: error - detected an invalid format, '\0'or'/': next character */
        const char **path,      /* Pointer to the file path pointer */
        char *dirname           /* Pointer to directory name buffer {Name(8), Ext(3), NT flag(1)} */
)
{
        BYTE n, t, c, a, b;


        memset(dirname, ' ', 8+3);      /* Fill buffer with spaces */
        a = 0; b = 0x18;        /* NT flag */
        n = 0; t = 8;
        for (;;) {
                c = *(*path)++;
                if (c == '\0' || c == '/') {            /* Reached to end of str or directory separator */
                        if (n == 0) break;
                        dirname[11] = _USE_NTFLAG ? (a & b) : 0;
                        return c;
                }
                if (c <= ' ' || c == 0x7F) break;               /* Reject invisible chars */
                if (c == '.') {
                        if (!(a & 1) && n >= 1 && n <= 8) {     /* Enter extension part */
                                n = 8; t = 11; continue;
                        }
                        break;
                }
                if (_USE_SJIS &&
                        ((c >= 0x81 && c <= 0x9F) ||    /* Accept S-JIS code */
                    (c >= 0xE0 && c <= 0xFC))) {
                        if (n == 0 && c == 0xE5)                /* Change heading \xE5 to \x05 */
                                c = 0x05;
                        a ^= 0x01; goto md_l2;
                }
                if (c == '"') break;                            /* Reject " */
                if (c <= ')') goto md_l1;                       /* Accept ! # $ % & ' ( ) */
                if (c <= ',') break;                            /* Reject * + , */
                if (c <= '9') goto md_l1;                       /* Accept - 0-9 */
                if (c <= '?') break;                            /* Reject : ; < = > ? */
                if (!(a & 1)) { /* These checks are not applied to S-JIS 2nd byte */
                        if (c == '|') break;                    /* Reject | */
                        if (c >= '[' && c <= ']') break;/* Reject [ \ ] */
                        if (_USE_NTFLAG && c >= 'A' && c <= 'Z')
                                (t == 8) ? (b &= 0xF7) : (b &= 0xEF);
                        if (c >= 'a' && c <= 'z') {             /* Convert to upper case */
                                c -= 0x20;
                                if (_USE_NTFLAG) (t == 8) ? (a |= 0x08) : (a |= 0x10);
                        }
                }
        md_l1:
                a &= 0xFE;
        md_l2:
                if (n >= t) break;
                dirname[n++] = c;
        }
        return 1;
}




/*-----------------------------------------------------------------------*/
/* Trace a file path                                                     */
/*-----------------------------------------------------------------------*/

static
FRESULT trace_path (    /* FR_OK(0): successful, !=0: error code */
        DIR *dj,                        /* Pointer to directory object to return last directory */
        char *fn,                       /* Pointer to last segment name to return {file(8),ext(3),attr(1)} */
        const char *path,       /* Full-path string to trace a file or directory */
        BYTE **dir                      /* Pointer to pointer to found entry to retutn */
)
{
        DWORD clust;
        char ds;
        BYTE *dptr = NULL;
        FATFS *fs = dj->fs;


        /* Initialize directory object */
        clust = fs->dirbase;
        if (fs->fs_type == FS_FAT32) {
                dj->clust = dj->sclust = clust;
                dj->sect = clust2sect(fs, clust);
        } else {
                dj->clust = dj->sclust = 0;
                dj->sect = clust;
        }
        dj->index = 0;

        if (*path == '\0') {                                    /* Null path means the root directory */
                *dir = NULL; return FR_OK;
        }

        for (;;) {
                ds = make_dirfile(&path, fn);                   /* Get a paragraph into fn[] */
                if (ds == 1) return FR_INVALID_NAME;
                for (;;) {
                        if (!move_window(fs, dj->sect)) return FR_RW_ERROR;
                        dptr = &fs->win[(dj->index & ((SS(fs) - 1) / 32)) * 32];        /* Pointer to the directory entry */
                        if (dptr[DIR_Name] == 0)                                                /* Has it reached to end of dir? */
                                return !ds ? FR_NO_FILE : FR_NO_PATH;
                        if (dptr[DIR_Name] != 0xE5                                              /* Matched? */
                                && !(dptr[DIR_Attr] & AM_VOL)
                                && !memcmp(&dptr[DIR_Name], fn, 8+3) ) break;
                        if (!next_dir_entry(dj))                                                /* Next directory pointer */
                                return !ds ? FR_NO_FILE : FR_NO_PATH;
                }
                if (!ds) { *dir = dptr; return FR_OK; }                         /* Matched with end of path */
                if (!(dptr[DIR_Attr] & AM_DIR)) return FR_NO_PATH;      /* Cannot trace because it is a file */
                clust = ((DWORD)LD_WORD(&dptr[DIR_FstClusHI]) << 16) | LD_WORD(&dptr[DIR_FstClusLO]); /* Get cluster# of the directory */
                dj->clust = dj->sclust = clust;                         /* Restart scanning at the new directory */
                dj->sect = clust2sect(fs, clust);
                dj->index = 2;
        }
}




/*-----------------------------------------------------------------------*/
/* Reserve a directory entry                                             */
/*-----------------------------------------------------------------------*/

#if !_FS_READONLY
static
FRESULT reserve_direntry (      /* FR_OK: successful, FR_DENIED: no free entry, FR_RW_ERROR: a disk error occured */
        DIR *dj,                                /* Target directory to create new entry */
        BYTE **dir                              /* Pointer to pointer to created entry to retutn */
)
{
        DWORD clust, sector;
        BYTE c, n, *dptr;
        FATFS *fs = dj->fs;


        /* Re-initialize directory object */
        clust = dj->sclust;
        if (clust != 0) {       /* Dyanmic directory table */
                dj->clust = clust;
                dj->sect = clust2sect(fs, clust);
        } else {                        /* Static directory table */
                dj->sect = fs->dirbase;
        }
        dj->index = 0;

        do {
                if (!move_window(fs, dj->sect)) return FR_RW_ERROR;
                dptr = &fs->win[(dj->index & ((SS(dj->fs) - 1) / 32)) * 32];    /* Pointer to the directory entry */
                c = dptr[DIR_Name];
                if (c == 0 || c == 0xE5) {              /* Found an empty entry */
                        *dir = dptr; return FR_OK;
                }
        } while (next_dir_entry(dj));           /* Next directory pointer */
        /* Reached to end of the directory table */

        /* Abort when it is a static table or could not stretch dynamic table */
        if (clust == 0 || !(clust = create_chain(fs, dj->clust))) return FR_DENIED;
        if (clust == 1 || !move_window(fs, 0)) return FR_RW_ERROR;

        /* Cleanup the expanded table */
        fs->winsect = sector = clust2sect(fs, clust);
        memset(fs->win, 0, SS(fs));
        for (n = fs->csize; n; n--) {
                if (disk_write(fs->drive, fs->win, sector, 1) != RES_OK)
                        return FR_RW_ERROR;
                sector++;
        }
        fs->winflag = 1;
        *dir = fs->win;

        return FR_OK;
}
#endif /* !_FS_READONLY */




/*-----------------------------------------------------------------------*/
/* Load boot record and check if it is an FAT boot record                */
/*-----------------------------------------------------------------------*/

static
BYTE check_fs ( /* 0:The FAT boot record, 1:Valid boot record but not an FAT, 2:Not a boot record or error */
        FATFS *fs,      /* File system object */
        DWORD sect      /* Sector# (lba) to check if it is an FAT boot record or not */
)
{
        if (disk_read(fs->drive, fs->win, sect, 1) != RES_OK)   /* Load boot record */
                return 2;
        if (LD_WORD(&fs->win[BS_55AA]) != 0xAA55)                               /* Check record signature (always placed at offset 510 even if the sector size is >512) */
                return 2;

        if (!memcmp(&fs->win[BS_FilSysType], "FAT", 3))                 /* Check FAT signature */
                return 0;
        if (!memcmp(&fs->win[BS_FilSysType32], "FAT32", 5) && !(fs->win[BPB_ExtFlags] & 0x80))
                return 0;

        return 1;
}




/*-----------------------------------------------------------------------*/
/* Make sure that the file system is valid                               */
/*-----------------------------------------------------------------------*/

static
FRESULT auto_mount (    /* FR_OK(0): successful, !=0: any error occured */
        const char **path,      /* Pointer to pointer to the path name (drive number) */
        FATFS **rfs,            /* Pointer to pointer to the found file system object */
        BYTE chk_wp                     /* !=0: Check media write protection for write access */
)
{
        BYTE drv, fmt, *tbl;
        DSTATUS stat;
        DWORD bootsect, fatsize, totalsect, maxclust;
        const char *p = *path;
        FATFS *fs;


        /* Get drive number from the path name */
        while (*p == ' ') p++;          /* Strip leading spaces */
        drv = p[0] - '0';                        /* Is there a drive number? */
        if (drv <= 9 && p[1] == ':')
                p += 2;                         /* Found a drive number, get and strip it */
        else
                drv = 0;                        /* No drive number is given, use drive number 0 as default */
        if (*p == '/') p++;             /* Strip heading slash */
        *path = p;                              /* Return pointer to the path name */

        /* Check if the drive number is valid or not */
        if (drv >= _DRIVES) return FR_INVALID_DRIVE;    /* Is the drive number valid? */
        *rfs = fs = FatFs[drv];                                 /* Returen pointer to the corresponding file system object */
        if (!fs) return FR_NOT_ENABLED;                 /* Is the file system object registered? */

        if (fs->fs_type) {                                              /* If the logical drive has been mounted */
                stat = disk_status(fs->drive);
                if (!(stat & STA_NOINIT)) {                     /* and physical drive is kept initialized (has not been changed), */
#if !_FS_READONLY
                        if (chk_wp && (stat & STA_PROTECT))     /* Check write protection if needed */
                                return FR_WRITE_PROTECTED;
#endif
                        return FR_OK;                                   /* The file system object is valid */
                }
        }

        /* The logical drive must be re-mounted. Following code attempts to mount the logical drive */

        memset(fs, 0, sizeof(FATFS));           /* Clean-up the file system object */
        fs->drive = LD2PD(drv);                         /* Bind the logical drive and a physical drive */
        stat = disk_initialize(fs->drive);      /* Initialize low level disk I/O layer */
        if (stat & STA_NOINIT)                          /* Check if the drive is ready */
                return FR_NOT_READY;
#if S_MAX_SIZ > 512                                             /* Get disk sector size if needed */
        if (disk_ioctl(drv, GET_SECTOR_SIZE, &SS(fs)) != RES_OK || SS(fs) > S_MAX_SIZ)
                return FR_NO_FILESYSTEM;
#endif
#if !_FS_READONLY
        if (chk_wp && (stat & STA_PROTECT))     /* Check write protection if needed */
                return FR_WRITE_PROTECTED;
#endif
        /* Search FAT partition on the drive */
        fmt = check_fs(fs, bootsect = 0);       /* Check sector 0 as an SFD format */
        if (fmt == 1) {                                         /* Not an FAT boot record, it may be patitioned */
                /* Check a partition listed in top of the partition table */
                tbl = &fs->win[MBR_Table + LD2PT(drv) * 16];    /* Partition table */
                if (tbl[4]) {                                                                   /* Is the partition existing? */
                        bootsect = LD_DWORD(&tbl[8]);                           /* Partition offset in LBA */
                        fmt = check_fs(fs, bootsect);                           /* Check the partition */
                }
        }
        if (fmt || LD_WORD(&fs->win[BPB_BytsPerSec]) != SS(fs)) /* No valid FAT patition is found */
                return FR_NO_FILESYSTEM;

        /* Initialize the file system object */
        fatsize = LD_WORD(&fs->win[BPB_FATSz16]);                       /* Number of sectors per FAT */
        if (!fatsize) fatsize = LD_DWORD(&fs->win[BPB_FATSz32]);
        fs->sects_fat = fatsize;
        fs->n_fats = fs->win[BPB_NumFATs];                                      /* Number of FAT copies */
        fatsize *= fs->n_fats;                                                          /* (Number of sectors in FAT area) */
        fs->fatbase = bootsect + LD_WORD(&fs->win[BPB_RsvdSecCnt]); /* FAT start sector (lba) */
        fs->csize = fs->win[BPB_SecPerClus];                            /* Number of sectors per cluster */
        fs->n_rootdir = LD_WORD(&fs->win[BPB_RootEntCnt]);      /* Nmuber of root directory entries */
        totalsect = LD_WORD(&fs->win[BPB_TotSec16]);            /* Number of sectors on the file system */
        if (!totalsect) totalsect = LD_DWORD(&fs->win[BPB_TotSec32]);
        fs->max_clust = maxclust = (totalsect                           /* max_clust = Last cluster# + 1 */
                - LD_WORD(&fs->win[BPB_RsvdSecCnt]) - fatsize - fs->n_rootdir / (SS(fs)/32)
                ) / fs->csize + 2;

        fmt = FS_FAT12;                                                                         /* Determine the FAT sub type */
        if (maxclust >= 0xFF7) fmt = FS_FAT16;
        if (maxclust >= 0xFFF7) fmt = FS_FAT32;

        if (fmt == FS_FAT32)
                fs->dirbase = LD_DWORD(&fs->win[BPB_RootClus]); /* Root directory start cluster */
        else
                fs->dirbase = fs->fatbase + fatsize;                    /* Root directory start sector (lba) */
        fs->database = fs->fatbase + fatsize + fs->n_rootdir / (SS(fs)/32);     /* Data start sector (lba) */

#if !_FS_READONLY
        /* Initialize allocation information */
        fs->free_clust = 0xFFFFFFFF;
#if _USE_FSINFO
        /* Get fsinfo if needed */
        if (fmt == FS_FAT32) {
                fs->fsi_sector = bootsect + LD_WORD(&fs->win[BPB_FSInfo]);
                if (disk_read(fs->drive, fs->win, fs->fsi_sector, 1) == RES_OK &&
                        LD_WORD(&fs->win[BS_55AA]) == 0xAA55 &&
                        LD_DWORD(&fs->win[FSI_LeadSig]) == 0x41615252 &&
                        LD_DWORD(&fs->win[FSI_StrucSig]) == 0x61417272) {
                        fs->last_clust = LD_DWORD(&fs->win[FSI_Nxt_Free]);
                        fs->free_clust = LD_DWORD(&fs->win[FSI_Free_Count]);
                }
        }
#endif
#endif

        fs->fs_type = fmt;                      /* FAT syb-type */
        fs->id = ++fsid;                        /* File system mount ID */
        return FR_OK;
}




/*-----------------------------------------------------------------------*/
/* Check if the file/dir object is valid or not                          */
/*-----------------------------------------------------------------------*/

static
FRESULT validate (              /* FR_OK(0): The object is valid, !=0: Invalid */
        const FATFS *fs,        /* Pointer to the file system object */
        WORD id                         /* Member id of the target object to be checked */
)
{
        if (!fs || !fs->fs_type || fs->id != id)
                return FR_INVALID_OBJECT;
        if (disk_status(fs->drive) & STA_NOINIT)
                return FR_NOT_READY;

        return FR_OK;
}




/*--------------------------------------------------------------------------

   Public Functions

--------------------------------------------------------------------------*/



/*-----------------------------------------------------------------------*/
/* Mount/Unmount a Locical Drive                                         */
/*-----------------------------------------------------------------------*/

FRESULT f_mount (
        BYTE drv,               /* Logical drive number to be mounted/unmounted */
        FATFS *fs               /* Pointer to new file system object (NULL for unmount)*/
)
{
        if (drv >= _DRIVES) return FR_INVALID_DRIVE;

        if (FatFs[drv]) FatFs[drv]->fs_type = 0;        /* Clear old object */

        FatFs[drv] = fs;                        /* Register and clear new object */
        if (fs) fs->fs_type = 0;

        return FR_OK;
}




/*-----------------------------------------------------------------------*/
/* Open or Create a File                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_open (
        FIL *fp,                        /* Pointer to the blank file object */
        const char *path,       /* Pointer to the file name */
        BYTE mode                       /* Access mode and file open mode flags */
)
{
        FRESULT res;
        DIR dj;
        BYTE *dir;
        char fn[8+3+1];


        fp->fs = NULL;          /* Clear file object */
#if !_FS_READONLY
        mode &= (FA_READ|FA_WRITE|FA_CREATE_ALWAYS|FA_OPEN_ALWAYS|FA_CREATE_NEW);
        res = auto_mount(&path, &dj.fs, (BYTE)(mode & (FA_WRITE|FA_CREATE_ALWAYS|FA_OPEN_ALWAYS|FA_CREATE_NEW)));
#else
        mode &= FA_READ;
        res = auto_mount(&path, &dj.fs, 0);
#endif
        if (res != FR_OK) return res;
        res = trace_path(&dj, fn, path, &dir);  /* Trace the file path */

#if !_FS_READONLY
        /* Create or Open a file */
        if (mode & (FA_CREATE_ALWAYS|FA_OPEN_ALWAYS|FA_CREATE_NEW)) {
                DWORD ps, rs;
                if (res != FR_OK) {             /* No file, create new */
                        if (res != FR_NO_FILE) return res;
                        res = reserve_direntry(&dj, &dir);
                        if (res != FR_OK) return res;
                        memset(dir, 0, 32);             /* Initialize the new entry with open name */
                        memcpy(&dir[DIR_Name], fn, 8+3);
                        dir[DIR_NTres] = fn[11];
                        mode |= FA_CREATE_ALWAYS;
                }
                else {                                  /* Any object is already existing */
                        if (mode & FA_CREATE_NEW)                       /* Cannot create new */
                                return FR_EXIST;
                        if (!dir || (dir[DIR_Attr] & (AM_RDO|AM_DIR)))  /* Cannot overwrite it (R/O or DIR) */
                                return FR_DENIED;
                        if (mode & FA_CREATE_ALWAYS) {          /* Resize it to zero if needed */
                                rs = ((DWORD)LD_WORD(&dir[DIR_FstClusHI]) << 16) | LD_WORD(&dir[DIR_FstClusLO]);        /* Get start cluster */
                                ST_WORD(&dir[DIR_FstClusHI], 0);        /* cluster = 0 */
                                ST_WORD(&dir[DIR_FstClusLO], 0);
                                ST_DWORD(&dir[DIR_FileSize], 0);        /* size = 0 */
                                dj.fs->winflag = 1;
                                ps = dj.fs->winsect;                    /* Remove the cluster chain */
                                if (!remove_chain(dj.fs, rs) || !move_window(dj.fs, ps))
                                        return FR_RW_ERROR;
                                dj.fs->last_clust = rs - 1;             /* Reuse the cluster hole */
                        }
                }
                if (mode & FA_CREATE_ALWAYS) {
                        dir[DIR_Attr] = 0;                                      /* Reset attribute */
                        ps = get_fattime();
                        ST_DWORD(&dir[DIR_CrtTime], ps);        /* Created time */
                        dj.fs->winflag = 1;
                        mode |= FA__WRITTEN;                            /* Set file changed flag */
                }
        }
        /* Open an existing file */
        else {
#endif /* !_FS_READONLY */
                if (res != FR_OK) return res;                   /* Trace failed */
                if (!dir || (dir[DIR_Attr] & AM_DIR))   /* It is a directory */
                        return FR_NO_FILE;
#if !_FS_READONLY
                if ((mode & FA_WRITE) && (dir[DIR_Attr] & AM_RDO)) /* R/O violation */
                        return FR_DENIED;
        }
        fp->dir_sect = dj.fs->winsect;          /* Pointer to the directory entry */
        fp->dir_ptr = dir;
#endif
        fp->flag = mode;                                        /* File access mode */
        fp->org_clust =                                         /* File start cluster */
                ((DWORD)LD_WORD(&dir[DIR_FstClusHI]) << 16) | LD_WORD(&dir[DIR_FstClusLO]);
        fp->fsize = LD_DWORD(&dir[DIR_FileSize]);       /* File size */
        fp->fptr = 0; fp->csect = 255;          /* File pointer */
        fp->curr_sect = 0;
        fp->fs = dj.fs; fp->id = dj.fs->id;     /* Owner file system object of the file */

        return FR_OK;
}




/*-----------------------------------------------------------------------*/
/* Read File                                                             */
/*-----------------------------------------------------------------------*/

FRESULT f_read (
        FIL *fp,                /* Pointer to the file object */
        void *buff,             /* Pointer to data buffer */
        UINT btr,               /* Number of bytes to read */
        UINT *br                /* Pointer to number of bytes read */
)
{
        FRESULT res;
        DWORD clust, sect, remain;
        UINT rcnt, cc;
        BYTE *rbuff = buff;


        *br = 0;
        res = validate(fp->fs, fp->id);                                 /* Check validity of the object */
        if (res != FR_OK) return res;
        if (fp->flag & FA__ERROR) return FR_RW_ERROR;   /* Check error flag */
        if (!(fp->flag & FA_READ)) return FR_DENIED;    /* Check access mode */
        remain = fp->fsize - fp->fptr;
        if (btr > remain) btr = (UINT)remain;                   /* Truncate btr by remaining bytes */

        for ( ;  btr;                                                                   /* Repeat until all data transferred */
                rbuff += rcnt, fp->fptr += rcnt, *br += rcnt, btr -= rcnt) {
                if ((fp->fptr % SS(fp->fs)) == 0) {                     /* On the sector boundary? */
                        if (fp->csect >= fp->fs->csize) {               /* On the cluster boundary? */
                                clust = (fp->fptr == 0) ?                       /* On the top of the file? */
                                        fp->org_clust : get_cluster(fp->fs, fp->curr_clust);
                                if (clust < 2 || clust >= fp->fs->max_clust) goto fr_error;
                                fp->curr_clust = clust;                         /* Update current cluster */
                                fp->csect = 0;                                          /* Reset sector address in the cluster */
                        }
                        sect = clust2sect(fp->fs, fp->curr_clust) + fp->csect;  /* Get current sector */
                        cc = btr / SS(fp->fs);                                  /* When remaining bytes >= sector size, */
                        if (cc) {                                                               /* Read maximum contiguous sectors directly */
                                if (fp->csect + cc > fp->fs->csize)     /* Clip at cluster boundary */
                                        cc = fp->fs->csize - fp->csect;
                                if (disk_read(fp->fs->drive, rbuff, sect, (BYTE)cc) != RES_OK)
                                        goto fr_error;
                                fp->csect += (BYTE)cc;                          /* Next sector address in the cluster */
                                rcnt = SS(fp->fs) * cc;                         /* Number of bytes transferred */
                                continue;
                        }
                        if (sect != fp->curr_sect) {                    /* Is window offset changed? */
#if !_FS_READONLY
                                if (fp->flag & FA__DIRTY) {                     /* Write back file I/O buffer if needed */
                                        if (disk_write(fp->fs->drive, fp->buffer, fp->curr_sect, 1) != RES_OK)
                                                goto fr_error;
                                        fp->flag &= (BYTE)~FA__DIRTY;
                                }
#endif
                                if (disk_read(fp->fs->drive, fp->buffer, sect, 1) != RES_OK)    /* Fill file I/O buffer with file data */
                                        goto fr_error;
                                fp->curr_sect = sect;
                        }
                        fp->csect++;                                                    /* Next sector address in the cluster */
                }
                rcnt = SS(fp->fs) - (fp->fptr % SS(fp->fs));    /* Get partial sector from file I/O buffer */
                if (rcnt > btr) rcnt = btr;
                memcpy(rbuff, &fp->buffer[fp->fptr % SS(fp->fs)], rcnt);
        }

        return FR_OK;

fr_error:       /* Abort this file due to an unrecoverable error */
        fp->flag |= FA__ERROR;
        return FR_RW_ERROR;
}




#if !_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Write File                                                            */
/*-----------------------------------------------------------------------*/

FRESULT f_write (
        FIL *fp,                        /* Pointer to the file object */
        const void *buff,       /* Pointer to the data to be written */
        UINT btw,                       /* Number of bytes to write */
        UINT *bw                        /* Pointer to number of bytes written */
)
{
        FRESULT res;
        DWORD clust, sect;
        UINT wcnt, cc;
        const BYTE *wbuff = buff;


        *bw = 0;
        res = validate(fp->fs, fp->id);                                 /* Check validity of the object */
        if (res != FR_OK) return res;
        if (fp->flag & FA__ERROR) return FR_RW_ERROR;   /* Check error flag */
        if (!(fp->flag & FA_WRITE)) return FR_DENIED;   /* Check access mode */
        if (fp->fsize + btw < fp->fsize) return FR_OK;  /* File size cannot reach 4GB */

        for ( ;  btw;                                                                   /* Repeat until all data transferred */
                wbuff += wcnt, fp->fptr += wcnt, *bw += wcnt, btw -= wcnt) {
                if ((fp->fptr % SS(fp->fs)) == 0) {                     /* On the sector boundary? */
                        if (fp->csect >= fp->fs->csize) {               /* On the cluster boundary? */
                                if (fp->fptr == 0) {                            /* On the top of the file? */
                                        clust = fp->org_clust;                  /* Follow from the origin */
                                        if (clust == 0)                                 /* When there is no cluster chain, */
                                                fp->org_clust = clust = create_chain(fp->fs, 0);        /* Create a new cluster chain */
                                } else {                                                        /* Middle or end of the file */
                                        clust = create_chain(fp->fs, fp->curr_clust);                   /* Trace or streach cluster chain */
                                }
                                if (clust == 0) break;                          /* Could not allocate a new cluster (disk full) */
                                if (clust == 1 || clust >= fp->fs->max_clust) goto fw_error;
                                fp->curr_clust = clust;                         /* Update current cluster */
                                fp->csect = 0;                                          /* Reset sector address in the cluster */
                        }
                        sect = clust2sect(fp->fs, fp->curr_clust) + fp->csect;  /* Get current sector */
                        cc = btw / SS(fp->fs);                                  /* When remaining bytes >= sector size, */
                        if (cc) {                                                               /* Write maximum contiguous sectors directly */
                                if (fp->csect + cc > fp->fs->csize)     /* Clip at cluster boundary */
                                        cc = fp->fs->csize - fp->csect;
                                if (disk_write(fp->fs->drive, wbuff, sect, (BYTE)cc) != RES_OK)
                                        goto fw_error;
                                fp->csect += (BYTE)cc;                          /* Next sector address in the cluster */
                                wcnt = SS(fp->fs) * cc;                         /* Number of bytes transferred */
                                continue;
                        }
                        if (sect != fp->curr_sect) {                    /* Is window offset changed? */
                                if (fp->flag & FA__DIRTY) {                     /* Write back file I/O buffer if needed */
                                        if (disk_write(fp->fs->drive, fp->buffer, fp->curr_sect, 1) != RES_OK)
                                                goto fw_error;
                                        fp->flag &= (BYTE)~FA__DIRTY;
                                }
                                if (fp->fptr < fp->fsize &&             /* Fill file I/O buffer with file data */
                                        disk_read(fp->fs->drive, fp->buffer, sect, 1) != RES_OK)
                                                goto fw_error;
                                fp->curr_sect = sect;
                        }
                        fp->csect++;                                                    /* Next sector address in the cluster */
                }
                wcnt = SS(fp->fs) - (fp->fptr % SS(fp->fs));    /* Put partial sector into file I/O buffer */
                if (wcnt > btw) wcnt = btw;
                memcpy(&fp->buffer[fp->fptr % SS(fp->fs)], wbuff, wcnt);
                fp->flag |= FA__DIRTY;
        }

        if (fp->fptr > fp->fsize) fp->fsize = fp->fptr; /* Update file size if needed */
        fp->flag |= FA__WRITTEN;                                                /* Set file changed flag */
        return FR_OK;

fw_error:       /* Abort this file due to an unrecoverable error */
        fp->flag |= FA__ERROR;
        return FR_RW_ERROR;
}




/*-----------------------------------------------------------------------*/
/* Synchronize the file object                                           */
/*-----------------------------------------------------------------------*/

FRESULT f_sync (
        FIL *fp         /* Pointer to the file object */
)
{
        FRESULT res;
        DWORD tim;
        BYTE *dir;


        res = validate(fp->fs, fp->id);         /* Check validity of the object */
        if (res == FR_OK) {
                if (fp->flag & FA__WRITTEN) {   /* Has the file been written? */
                        /* Write back data buffer if needed */
                        if (fp->flag & FA__DIRTY) {
                                if (disk_write(fp->fs->drive, fp->buffer, fp->curr_sect, 1) != RES_OK)
                                        return FR_RW_ERROR;
                                fp->flag &= (BYTE)~FA__DIRTY;
                        }
                        /* Update the directory entry */
                        if (!move_window(fp->fs, fp->dir_sect))
                                return FR_RW_ERROR;
                        dir = fp->dir_ptr;
                        dir[DIR_Attr] |= AM_ARC;                                                /* Set archive bit */
                        ST_DWORD(&dir[DIR_FileSize], fp->fsize);                /* Update file size */
                        ST_WORD(&dir[DIR_FstClusLO], fp->org_clust);    /* Update start cluster */
                        ST_WORD(&dir[DIR_FstClusHI], fp->org_clust >> 16);
                        tim = get_fattime();                                    /* Updated time */
                        ST_DWORD(&dir[DIR_WrtTime], tim);
                        fp->flag &= (BYTE)~FA__WRITTEN;
                        res = sync(fp->fs);
                }
        }
        return res;
}

#endif /* !_FS_READONLY */




/*-----------------------------------------------------------------------*/
/* Close File                                                            */
/*-----------------------------------------------------------------------*/

FRESULT f_close (
        FIL *fp         /* Pointer to the file object to be closed */
)
{
        FRESULT res;


#if !_FS_READONLY
        res = f_sync(fp);
#else
        res = validate(fp->fs, fp->id);
#endif
        if (res == FR_OK) fp->fs = NULL;
        return res;
}




#if _FS_MINIMIZE <= 2
/*-----------------------------------------------------------------------*/
/* Seek File R/W Pointer                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_lseek (
        FIL *fp,                /* Pointer to the file object */
        DWORD ofs               /* File pointer from top of file */
)
{
        FRESULT res;
        DWORD clust, csize, nsect, ifptr;


        res = validate(fp->fs, fp->id);         /* Check validity of the object */
        if (res != FR_OK) return res;
        if (fp->flag & FA__ERROR) return FR_RW_ERROR;
        if (ofs > fp->fsize                                     /* In read-only mode, clip offset with the file size */
#if !_FS_READONLY
                 && !(fp->flag & FA_WRITE)
#endif
                ) ofs = fp->fsize;

        ifptr = fp->fptr;
        fp->fptr = 0; fp->csect = 255;
        nsect = 0;
        if (ofs > 0) {
                csize = (DWORD)fp->fs->csize * SS(fp->fs);      /* Cluster size (byte) */
                if (ifptr > 0 &&
                        (ofs - 1) / csize >= (ifptr - 1) / csize) {/* When seek to same or following cluster, */
                        fp->fptr = (ifptr - 1) & ~(csize - 1);  /* start from the current cluster */
                        ofs -= fp->fptr;
                        clust = fp->curr_clust;
                } else {                                                                        /* When seek to back cluster, */
                        clust = fp->org_clust;                                  /* start from the first cluster */
#if !_FS_READONLY
                        if (clust == 0) {                                               /* If no cluster chain, create a new chain */
                                clust = create_chain(fp->fs, 0);
                                if (clust == 1) goto fk_error;
                                fp->org_clust = clust;
                        }
#endif
                        fp->curr_clust = clust;
                }
                if (clust != 0) {
                        while (ofs > csize) {                                   /* Cluster following loop */
#if !_FS_READONLY
                                if (fp->flag & FA_WRITE) {                      /* Check if in write mode or not */
                                        clust = create_chain(fp->fs, clust);    /* Force streached if in write mode */
                                        if (clust == 0) {                               /* When disk gets full, clip file size */
                                                ofs = csize; break;
                                        }
                                } else
#endif
                                        clust = get_cluster(fp->fs, clust);     /* Follow cluster chain if not in write mode */
                                if (clust < 2 || clust >= fp->fs->max_clust) goto fk_error;
                                fp->curr_clust = clust;
                                fp->fptr += csize;
                                ofs -= csize;
                        }
                        fp->fptr += ofs;
                        fp->csect = (BYTE)(ofs / SS(fp->fs));   /* Sector offset in the cluster */
                        if (ofs & (SS(fp->fs) - 1)) {
                                nsect = clust2sect(fp->fs, clust) + fp->csect;  /* Current sector */
                                fp->csect++;
                        }
                }
        }
        if (nsect && nsect != fp->curr_sect) {
#if !_FS_READONLY
                if (fp->flag & FA__DIRTY) {                     /* Write-back dirty buffer if needed */
                        if (disk_write(fp->fs->drive, fp->buffer, fp->curr_sect, 1) != RES_OK)
                                goto fk_error;
                        fp->flag &= (BYTE)~FA__DIRTY;
                }
#endif
                if (disk_read(fp->fs->drive, fp->buffer, nsect, 1) != RES_OK)
                        goto fk_error;
                fp->curr_sect = nsect;
        }

#if !_FS_READONLY
        if (fp->fptr > fp->fsize) {                     /* Set changed flag if the file was extended */
                fp->fsize = fp->fptr;
                fp->flag |= FA__WRITTEN;
        }
#endif

        return FR_OK;

fk_error:       /* Abort this file due to an unrecoverable error */
        fp->flag |= FA__ERROR;
        return FR_RW_ERROR;
}




#if _FS_MINIMIZE <= 1
/*-----------------------------------------------------------------------*/
/* Create a directroy object                                             */
/*-----------------------------------------------------------------------*/

FRESULT f_opendir (
        DIR *dj,                        /* Pointer to directory object to create */
        const char *path        /* Pointer to the directory path */
)
{
        FRESULT res;
        BYTE *dir;
        char fn[8+3+1];


        res = auto_mount(&path, &dj->fs, 0);
        if (res == FR_OK) {
                res = trace_path(dj, fn, path, &dir);   /* Trace the directory path */
                if (res == FR_OK) {                                             /* Trace completed */
                        if (dir) {                                                      /* It is not the root dir */
                                if (dir[DIR_Attr] & AM_DIR) {   /* The entry is a directory */
                                        dj->clust = ((DWORD)LD_WORD(&dir[DIR_FstClusHI]) << 16) | LD_WORD(&dir[DIR_FstClusLO]);
                                        dj->sect = clust2sect(dj->fs, dj->clust);
                                        dj->index = 2;
                                } else {                                                /* The entry is not a directory */
                                        res = FR_NO_FILE;
                                }
                        }
                        dj->id = dj->fs->id;
                }
        }

        return res;
}




/*-----------------------------------------------------------------------*/
/* Read Directory Entry in Sequense                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_readdir (
        DIR *dj,                        /* Pointer to the directory object */
        FILINFO *finfo          /* Pointer to file information to return */
)
{
        BYTE *dir, c, res;


        res = validate(dj->fs, dj->id);                 /* Check validity of the object */
        if (res != FR_OK) return res;

        finfo->fname[0] = 0;
        while (dj->sect) {
                if (!move_window(dj->fs, dj->sect))
                        return FR_RW_ERROR;
                dir = &dj->fs->win[(dj->index & ((SS(dj->fs) - 1) >> 5)) * 32]; /* pointer to the directory entry */
                c = dir[DIR_Name];
                if (c == 0) break;                                                      /* Has it reached to end of dir? */
                if (c != 0xE5 && !(dir[DIR_Attr] & AM_VOL))     /* Is it a valid entry? */
                        get_fileinfo(finfo, dir);
                if (!next_dir_entry(dj)) dj->sect = 0;          /* Next entry */
                if (finfo->fname[0]) break;                                     /* Found valid entry */
        }

        return FR_OK;
}




#if _FS_MINIMIZE == 0
/*-----------------------------------------------------------------------*/
/* Get File Status                                                       */
/*-----------------------------------------------------------------------*/

FRESULT f_stat (
        const char *path,       /* Pointer to the file path */
        FILINFO *finfo          /* Pointer to file information to return */
)
{
        FRESULT res;
        DIR dj;
        BYTE *dir;
        char fn[8+3+1];


        res = auto_mount(&path, &dj.fs, 0);
        if (res == FR_OK) {
                res = trace_path(&dj, fn, path, &dir);  /* Trace the file path */
                if (res == FR_OK) {                                             /* Trace completed */
                        if (dir)        /* Found an object */
                                get_fileinfo(finfo, dir);
                        else            /* It is root dir */
                                res = FR_INVALID_NAME;
                }
        }

        return res;
}



#if !_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Truncate File                                                         */
/*-----------------------------------------------------------------------*/

FRESULT f_truncate (
        FIL *fp         /* Pointer to the file object */
)
{
        FRESULT res;
        DWORD ncl;


        res = validate(fp->fs, fp->id);         /* Check validity of the object */
        if (res != FR_OK) return res;
        if (fp->flag & FA__ERROR) return FR_RW_ERROR;   /* Check error flag */
        if (!(fp->flag & FA_WRITE)) return FR_DENIED;   /* Check access mode */

        if (fp->fsize > fp->fptr) {
                fp->fsize = fp->fptr;   /* Set file size to current R/W point */
                fp->flag |= FA__WRITTEN;
                if (fp->fptr == 0) {    /* When set file size to zero, remove entire cluster chain */
                        if (!remove_chain(fp->fs, fp->org_clust)) goto ft_error;
                        fp->org_clust = 0;
                } else {                                /* When truncate a part of the file, remove remaining clusters */
                        ncl = get_cluster(fp->fs, fp->curr_clust);
                        if (ncl < 2) goto ft_error;
                        if (ncl < fp->fs->max_clust) {
                                if (!put_cluster(fp->fs, fp->curr_clust, 0x0FFFFFFF)) goto ft_error;
                                if (!remove_chain(fp->fs, ncl)) goto ft_error;
                        }
                }
        }

        return FR_OK;

ft_error:       /* Abort this file due to an unrecoverable error */
        fp->flag |= FA__ERROR;
        return FR_RW_ERROR;
}




/*-----------------------------------------------------------------------*/
/* Get Number of Free Clusters                                           */
/*-----------------------------------------------------------------------*/

FRESULT f_getfree (
        const char *drv,        /* Pointer to the logical drive number (root dir) */
        DWORD *nclust,          /* Pointer to the variable to return number of free clusters */
        FATFS **fatfs           /* Pointer to pointer to corresponding file system object to return */
)
{
        FRESULT res;
        DWORD n, clust, sect;
        BYTE fat, f, *p;


        /* Get drive number */
        res = auto_mount(&drv, fatfs, 0);
        if (res != FR_OK) return res;

        /* If number of free cluster is valid, return it without cluster scan. */
        if ((*fatfs)->free_clust <= (*fatfs)->max_clust - 2) {
                *nclust = (*fatfs)->free_clust;
                return FR_OK;
        }

        /* Get number of free clusters */
        fat = (*fatfs)->fs_type;
        n = 0;
        if (fat == FS_FAT12) {
                clust = 2;
                do {
                        if ((WORD)get_cluster(*fatfs, clust) == 0) n++;
                } while (++clust < (*fatfs)->max_clust);
        } else {
                clust = (*fatfs)->max_clust;
                sect = (*fatfs)->fatbase;
                f = 0; p = 0;
                do {
                        if (!f) {
                                if (!move_window(*fatfs, sect++)) return FR_RW_ERROR;
                                p = (*fatfs)->win;
                        }
                        if (fat == FS_FAT16) {
                                if (LD_WORD(p) == 0) n++;
                                p += 2; f += 1;
                        } else {
                                if (LD_DWORD(p) == 0) n++;
                                p += 4; f += 2;
                        }
                } while (--clust);
        }
        (*fatfs)->free_clust = n;
#if _USE_FSINFO
        if (fat == FS_FAT32) (*fatfs)->fsi_flag = 1;
#endif

        *nclust = n;
        return FR_OK;
}




/*-----------------------------------------------------------------------*/
/* Delete a File or Directory                                            */
/*-----------------------------------------------------------------------*/

FRESULT f_unlink (
        const char *path                /* Pointer to the file or directory path */
)
{
        FRESULT res;
        DIR dj;
        BYTE *dir, *sdir;
        DWORD dclust, dsect;
        char fn[8+3+1];


        res = auto_mount(&path, &dj.fs, 1);
        if (res != FR_OK) return res;
        res = trace_path(&dj, fn, path, &dir);  /* Trace the file path */
        if (res != FR_OK) return res;                   /* Trace failed */
        if (!dir) return FR_INVALID_NAME;               /* It is the root directory */
        if (dir[DIR_Attr] & AM_RDO) return FR_DENIED;   /* It is a R/O object */
        dsect = dj.fs->winsect;
        dclust = ((DWORD)LD_WORD(&dir[DIR_FstClusHI]) << 16) | LD_WORD(&dir[DIR_FstClusLO]);

        if (dir[DIR_Attr] & AM_DIR) {                   /* It is a sub-directory */
                dj.clust = dclust;                                      /* Check if the sub-dir is empty or not */
                dj.sect = clust2sect(dj.fs, dclust);
                dj.index = 2;
                do {
                        if (!move_window(dj.fs, dj.sect)) return FR_RW_ERROR;
                        sdir = &dj.fs->win[(dj.index & ((SS(dj.fs) - 1) >> 5)) * 32];
                        if (sdir[DIR_Name] == 0) break;
                        if (sdir[DIR_Name] != 0xE5 && !(sdir[DIR_Attr] & AM_VOL))
                                return FR_DENIED;       /* The directory is not empty */
                } while (next_dir_entry(&dj));
        }

        if (!move_window(dj.fs, dsect)) return FR_RW_ERROR;     /* Mark the directory entry 'deleted' */
        dir[DIR_Name] = 0xE5;
        dj.fs->winflag = 1;
        if (!remove_chain(dj.fs, dclust)) return FR_RW_ERROR;   /* Remove the cluster chain */

        return sync(dj.fs);
}




/*-----------------------------------------------------------------------*/
/* Create a Directory                                                    */
/*-----------------------------------------------------------------------*/

FRESULT f_mkdir (
        const char *path                /* Pointer to the directory path */
)
{
        FRESULT res;
        DIR dj;
        BYTE *dir, *fw, n;
        char fn[8+3+1];
        DWORD sect, dsect, dclust, pclust, tim;


        res = auto_mount(&path, &dj.fs, 1);
        if (res != FR_OK) return res;
        res = trace_path(&dj, fn, path, &dir);  /* Trace the file path */
        if (res == FR_OK) return FR_EXIST;              /* Any file or directory is already existing */
        if (res != FR_NO_FILE) return res;

        res = reserve_direntry(&dj, &dir);              /* Reserve a directory entry */
        if (res != FR_OK) return res;
        sect = dj.fs->winsect;
        dclust = create_chain(dj.fs, 0);                /* Allocate a cluster for new directory table */
        if (dclust == 1) return FR_RW_ERROR;
        dsect = clust2sect(dj.fs, dclust);
        if (!dsect) return FR_DENIED;
        if (!move_window(dj.fs, dsect)) return FR_RW_ERROR;

        fw = dj.fs->win;
        memset(fw, 0, SS(dj.fs));                               /* Clear the new directory table */
        for (n = 1; n < dj.fs->csize; n++) {
                if (disk_write(dj.fs->drive, fw, ++dsect, 1) != RES_OK)
                        return FR_RW_ERROR;
        }
        memset(&fw[DIR_Name], ' ', 8+3);                /* Create "." entry */
        fw[DIR_Name] = '.';
        fw[DIR_Attr] = AM_DIR;
        tim = get_fattime();
        ST_DWORD(&fw[DIR_WrtTime], tim);
        memcpy(&fw[32], &fw[0], 32); fw[33] = '.';      /* Create ".." entry */
        ST_WORD(&fw[   DIR_FstClusLO], dclust);
        ST_WORD(&fw[   DIR_FstClusHI], dclust >> 16);
        pclust = dj.sclust;
        if (dj.fs->fs_type == FS_FAT32 && pclust == dj.fs->dirbase) pclust = 0;
        ST_WORD(&fw[32+DIR_FstClusLO], pclust);
        ST_WORD(&fw[32+DIR_FstClusHI], pclust >> 16);
        dj.fs->winflag = 1;

        if (!move_window(dj.fs, sect)) return FR_RW_ERROR;
        memset(&dir[0], 0, 32);                                         /* Initialize the new entry */
        memcpy(&dir[DIR_Name], fn, 8+3);                        /* Name */
        dir[DIR_NTres] = fn[11];
        dir[DIR_Attr] = AM_DIR;                                         /* Attribute */
        ST_DWORD(&dir[DIR_WrtTime], tim);                       /* Crated time */
        ST_WORD(&dir[DIR_FstClusLO], dclust);           /* Table start cluster */
        ST_WORD(&dir[DIR_FstClusHI], dclust >> 16);

        return sync(dj.fs);
}




/*-----------------------------------------------------------------------*/
/* Change File Attribute                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_chmod (
        const char *path,       /* Pointer to the file path */
        BYTE value,                     /* Attribute bits */
        BYTE mask                       /* Attribute mask to change */
)
{
        FRESULT res;
        DIR dj;
        BYTE *dir;
        char fn[8+3+1];


        res = auto_mount(&path, &dj.fs, 1);
        if (res == FR_OK) {
                res = trace_path(&dj, fn, path, &dir);  /* Trace the file path */
                if (res == FR_OK) {                             /* Trace completed */
                        if (!dir) {
                                res = FR_INVALID_NAME;  /* Root directory */
                        } else {
                                mask &= AM_RDO|AM_HID|AM_SYS|AM_ARC;    /* Valid attribute mask */
                                dir[DIR_Attr] = (value & mask) | (dir[DIR_Attr] & (BYTE)~mask); /* Apply attribute change */
                                res = sync(dj.fs);
                        }
                }
        }
        return res;
}




/*-----------------------------------------------------------------------*/
/* Change Timestamp                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_utime (
        const char *path,               /* Pointer to the file/directory name */
        const FILINFO *finfo    /* Pointer to the timestamp to be set */
)
{
        FRESULT res;
        DIR dj;
        BYTE *dir;
        char fn[8+3+1];


        res = auto_mount(&path, &dj.fs, 1);
        if (res == FR_OK) {
                res = trace_path(&dj, fn, path, &dir);  /* Trace the file path */
                if (res == FR_OK) {                             /* Trace completed */
                        if (!dir) {
                                res = FR_INVALID_NAME;  /* Root directory */
                        } else {
                                ST_WORD(&dir[DIR_WrtTime], finfo->ftime);
                                ST_WORD(&dir[DIR_WrtDate], finfo->fdate);
                                res = sync(dj.fs);
                        }
                }
        }
        return res;
}




/*-----------------------------------------------------------------------*/
/* Rename File/Directory                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_rename (
        const char *path_old,   /* Pointer to the old name */
        const char *path_new    /* Pointer to the new name */
)
{
        FRESULT res;
        DIR dj;
        DWORD sect_old;
        BYTE *dir_old, *dir_new, direntry[32-11];
        char fn[8+3+1];


        res = auto_mount(&path_old, &dj.fs, 1);
        if (res != FR_OK) return res;

        res = trace_path(&dj, fn, path_old, &dir_old);  /* Check old object */
        if (res != FR_OK) return res;                           /* The old object is not found */
        if (!dir_old) return FR_NO_FILE;
        sect_old = dj.fs->winsect;                                      /* Save the object information */
        memcpy(direntry, &dir_old[DIR_Attr], 32-11);

        res = trace_path(&dj, fn, path_new, &dir_new);  /* Check new object */
        if (res == FR_OK) return FR_EXIST;                      /* The new object name is already existing */
        if (res != FR_NO_FILE) return res;                      /* Is there no old name? */
        res = reserve_direntry(&dj, &dir_new);          /* Reserve a directory entry */
        if (res != FR_OK) return res;

        memcpy(&dir_new[DIR_Attr], direntry, 32-11);    /* Create new entry */
        memcpy(&dir_new[DIR_Name], fn, 8+3);
        dir_new[DIR_NTres] = fn[11];
        dj.fs->winflag = 1;

        if (!move_window(dj.fs, sect_old)) return FR_RW_ERROR;  /* Delete old entry */
        dir_old[DIR_Name] = 0xE5;

        return sync(dj.fs);
}

#endif /* !_FS_READONLY */
#endif /* _FS_MINIMIZE == 0 */
#endif /* _FS_MINIMIZE <= 1 */
#endif /* _FS_MINIMIZE <= 2 */



#if _USE_MKFS && !_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Create File System on the Drive                                       */
/*-----------------------------------------------------------------------*/
#define N_ROOTDIR       512                     /* Multiple of 32 and <= 2048 */
#define N_FATS          1                       /* 1 or 2 */
#define MAX_SECTOR      64000000UL      /* Maximum partition size */
#define MIN_SECTOR      2000UL          /* Minimum partition size */



FRESULT f_mkfs (
        BYTE drv,                       /* Logical drive number */
        BYTE partition,         /* Partitioning rule 0:FDISK, 1:SFD */
        WORD allocsize          /* Allocation unit size [bytes] */
)
{
        BYTE fmt, m, *tbl;
        DWORD b_part, b_fat, b_dir, b_data;             /* Area offset (LBA) */
        DWORD n_part, n_rsv, n_fat, n_dir;              /* Area size */
        DWORD n_clust, n;
        FATFS *fs;
        DSTATUS stat;


        /* Check validity of the parameters */
        if (drv >= _DRIVES) return FR_INVALID_DRIVE;
        if (partition >= 2) return FR_MKFS_ABORTED;
        for (n = 512; n <= 32768U && n != allocsize; n <<= 1);
        if (n != allocsize) return FR_MKFS_ABORTED;

        /* Check mounted drive and clear work area */
        fs = FatFs[drv];
        if (!fs) return FR_NOT_ENABLED;
        fs->fs_type = 0;
        drv = LD2PD(drv);

        /* Get disk statics */
        stat = disk_initialize(drv);
        if (stat & STA_NOINIT) return FR_NOT_READY;
        if (stat & STA_PROTECT) return FR_WRITE_PROTECTED;
        if (disk_ioctl(drv, GET_SECTOR_COUNT, &n_part) != RES_OK || n_part < MIN_SECTOR)
                return FR_MKFS_ABORTED;
        if (n_part > MAX_SECTOR) n_part = MAX_SECTOR;
        b_part = (!partition) ? 63 : 0;         /* Boot sector */
        n_part -= b_part;
#if S_MAX_SIZ > 512                                             /* Check disk sector size */
        if (disk_ioctl(drv, GET_SECTOR_SIZE, &SS(fs)) != RES_OK
                || SS(fs) > S_MAX_SIZ
                || SS(fs) > allocsize)
                return FR_MKFS_ABORTED;
#endif
        allocsize /= SS(fs);            /* Number of sectors per cluster */

        /* Pre-compute number of clusters and FAT type */
        n_clust = n_part / allocsize;
        fmt = FS_FAT12;
        if (n_clust >= 0xFF5) fmt = FS_FAT16;
        if (n_clust >= 0xFFF5) fmt = FS_FAT32;

        /* Determine offset and size of FAT structure */
        switch (fmt) {
        case FS_FAT12:
                n_fat = ((n_clust * 3 + 1) / 2 + 3 + SS(fs) - 1) / SS(fs);
                n_rsv = 1 + partition;
                n_dir = N_ROOTDIR * 32 / SS(fs);
                break;
        case FS_FAT16:
                n_fat = ((n_clust * 2) + 4 + SS(fs) - 1) / SS(fs);
                n_rsv = 1 + partition;
                n_dir = N_ROOTDIR * 32 / SS(fs);
                break;
        default:
                n_fat = ((n_clust * 4) + 8 + SS(fs) - 1) / SS(fs);
                n_rsv = 33 - partition;
                n_dir = 0;
        }
        b_fat = b_part + n_rsv;                 /* FATs start sector */
        b_dir = b_fat + n_fat * N_FATS; /* Directory start sector */
        b_data = b_dir + n_dir;                 /* Data start sector */

        /* Align data start sector to erase block boundary (for flash memory media) */
        if (disk_ioctl(drv, GET_BLOCK_SIZE, &n) != RES_OK) return FR_MKFS_ABORTED;
        n = (b_data + n - 1) & ~(n - 1);
        n_fat += (n - b_data) / N_FATS;
        /* b_dir and b_data are no longer used below */

        /* Determine number of cluster and final check of validity of the FAT type */
        n_clust = (n_part - n_rsv - n_fat * N_FATS - n_dir) / allocsize;
        if (   (fmt == FS_FAT16 && n_clust < 0xFF5)
                || (fmt == FS_FAT32 && n_clust < 0xFFF5))
                return FR_MKFS_ABORTED;

        /* Create partition table if needed */
        if (!partition) {
                DWORD n_disk = b_part + n_part;

                tbl = &fs->win[MBR_Table];
                ST_DWORD(&tbl[0], 0x00010180);  /* Partition start in CHS */
                if (n_disk < 63UL * 255 * 1024) {       /* Partition end in CHS */
                        n_disk = n_disk / 63 / 255;
                        tbl[7] = (BYTE)n_disk;
                        tbl[6] = (BYTE)((n_disk >> 2) | 63);
                } else {
                        ST_WORD(&tbl[6], 0xFFFF);
                }
                tbl[5] = 254;
                if (fmt != FS_FAT32)                    /* System ID */
                        tbl[4] = (n_part < 0x10000) ? 0x04 : 0x06;
                else
                        tbl[4] = 0x0c;
                ST_DWORD(&tbl[8], 63);                  /* Partition start in LBA */
                ST_DWORD(&tbl[12], n_part);             /* Partition size in LBA */
                ST_WORD(&tbl[64], 0xAA55);              /* Signature */
                if (disk_write(drv, fs->win, 0, 1) != RES_OK)
                        return FR_RW_ERROR;
        }

        /* Create boot record */
        tbl = fs->win;                                                          /* Clear buffer */
        memset(tbl, 0, SS(fs));
        ST_DWORD(&tbl[BS_jmpBoot], 0x90FEEB);           /* Boot code (jmp $, nop) */
        ST_WORD(&tbl[BPB_BytsPerSec], SS(fs));          /* Sector size */
        tbl[BPB_SecPerClus] = (BYTE)allocsize;          /* Sectors per cluster */
        ST_WORD(&tbl[BPB_RsvdSecCnt], n_rsv);           /* Reserved sectors */
        tbl[BPB_NumFATs] = N_FATS;                                      /* Number of FATs */
        ST_WORD(&tbl[BPB_RootEntCnt], SS(fs) / 32 * n_dir); /* Number of rootdir entries */
        if (n_part < 0x10000) {                                         /* Number of total sectors */
                ST_WORD(&tbl[BPB_TotSec16], n_part);
        } else {
                ST_DWORD(&tbl[BPB_TotSec32], n_part);
        }
        tbl[BPB_Media] = 0xF8;                                          /* Media descripter */
        ST_WORD(&tbl[BPB_SecPerTrk], 63);                       /* Number of sectors per track */
        ST_WORD(&tbl[BPB_NumHeads], 255);                       /* Number of heads */
        ST_DWORD(&tbl[BPB_HiddSec], b_part);            /* Hidden sectors */
        n = get_fattime();                                                      /* Use current time as a VSN */
        if (fmt != FS_FAT32) {
                ST_DWORD(&tbl[BS_VolID], n);                    /* Volume serial number */
                ST_WORD(&tbl[BPB_FATSz16], n_fat);              /* Number of secters per FAT */
                tbl[BS_DrvNum] = 0x80;                                  /* Drive number */
                tbl[BS_BootSig] = 0x29;                                 /* Extended boot signature */
                memcpy(&tbl[BS_VolLab], "NO NAME    FAT     ", 19);     /* Volume lavel, FAT signature */
        } else {
                ST_DWORD(&tbl[BS_VolID32], n);                  /* Volume serial number */
                ST_DWORD(&tbl[BPB_FATSz32], n_fat);             /* Number of secters per FAT */
                ST_DWORD(&tbl[BPB_RootClus], 2);                /* Root directory cluster (2) */
                ST_WORD(&tbl[BPB_FSInfo], 1);                   /* FSInfo record (bs+1) */
                ST_WORD(&tbl[BPB_BkBootSec], 6);                /* Backup boot record (bs+6) */
                tbl[BS_DrvNum32] = 0x80;                                /* Drive number */
                tbl[BS_BootSig32] = 0x29;                               /* Extended boot signature */
                memcpy(&tbl[BS_VolLab32], "NO NAME    FAT32   ", 19);   /* Volume lavel, FAT signature */
        }
        ST_WORD(&tbl[BS_55AA], 0xAA55);                 /* Signature */
        if (disk_write(drv, tbl, b_part+0, 1) != RES_OK)
                return FR_RW_ERROR;
        if (fmt == FS_FAT32)
                disk_write(drv, tbl, b_part+6, 1);

        /* Initialize FAT area */
        for (m = 0; m < N_FATS; m++) {
                memset(tbl, 0, SS(fs));         /* 1st sector of the FAT  */
                if (fmt != FS_FAT32) {
                        n = (fmt == FS_FAT12) ? 0x00FFFFF8 : 0xFFFFFFF8;
                        ST_DWORD(&tbl[0], n);                   /* Reserve cluster #0-1 (FAT12/16) */
                } else {
                        ST_DWORD(&tbl[0], 0xFFFFFFF8);  /* Reserve cluster #0-1 (FAT32) */
                        ST_DWORD(&tbl[4], 0xFFFFFFFF);
                        ST_DWORD(&tbl[8], 0x0FFFFFFF);  /* Reserve cluster #2 for root dir */
                }
                if (disk_write(drv, tbl, b_fat++, 1) != RES_OK)
                        return FR_RW_ERROR;
                memset(tbl, 0, SS(fs));         /* Following FAT entries are filled by zero */
                for (n = 1; n < n_fat; n++) {
                        if (disk_write(drv, tbl, b_fat++, 1) != RES_OK)
                                return FR_RW_ERROR;
                }
        }

        /* Initialize Root directory */
        m = (BYTE)((fmt == FS_FAT32) ? allocsize : n_dir);
        do {
                if (disk_write(drv, tbl, b_fat++, 1) != RES_OK)
                        return FR_RW_ERROR;
        } while (--m);

        /* Create FSInfo record if needed */
        if (fmt == FS_FAT32) {
                ST_WORD(&tbl[BS_55AA], 0xAA55);
                ST_DWORD(&tbl[FSI_LeadSig], 0x41615252);
                ST_DWORD(&tbl[FSI_StrucSig], 0x61417272);
                ST_DWORD(&tbl[FSI_Free_Count], n_clust - 1);
                ST_DWORD(&tbl[FSI_Nxt_Free], 0xFFFFFFFF);
                disk_write(drv, tbl, b_part+1, 1);
                disk_write(drv, tbl, b_part+7, 1);
        }

        return (disk_ioctl(drv, CTRL_SYNC, NULL) == RES_OK) ? FR_OK : FR_RW_ERROR;
}

#endif /* _USE_MKFS && !_FS_READONLY */




#if _USE_STRFUNC >= 1
/*-----------------------------------------------------------------------*/
/* Get a string from the file                                            */
/*-----------------------------------------------------------------------*/
char* fgets (
        char* buff,     /* Pointer to the string buffer to read */
        int len,        /* Size of string buffer */
        FIL* fil        /* Pointer to the file object */
)
{
        int i = 0;
        char *p = buff;
        UINT rc;


        while (i < len - 1) {                   /* Read bytes until buffer gets filled */
                f_read(fil, p, 1, &rc);
                if (rc != 1) break;                     /* Break when no data to read */
#if _USE_STRFUNC >= 2
                if (*p == '\r') continue;       /* Strip '\r' */
#endif
                i++;
                if (*p++ == '\n') break;        /* Break when reached end of line */
        }
        *p = 0;
        return i ? buff : 0;                    /* When no data read (eof or error), return with error. */
}



#if !_FS_READONLY
#include <stdarg.h>
/*-----------------------------------------------------------------------*/
/* Put a character to the file                                           */
/*-----------------------------------------------------------------------*/
int fputc (
        int chr,        /* A character to be output */
        FIL* fil        /* Ponter to the file object */
)
{
        UINT bw;
        char c;


#if _USE_STRFUNC >= 2
        if (chr == '\n') fputc ('\r', fil);     /* LF -> CRLF conversion */
#endif
        if (!fil) {     /* Special value may be used to switch the destination to any other device */
        /*      put_console(chr);       */
                return chr;
        }
        c = (char)chr;
        f_write(fil, &c, 1, &bw);       /* Write a byte to the file */
        return bw ? chr : EOF;          /* Return the resulut */
}




/*-----------------------------------------------------------------------*/
/* Put a string to the file                                              */
/*-----------------------------------------------------------------------*/
int fputs (
        const char* str,        /* Pointer to the string to be output */
        FIL* fil                        /* Pointer to the file object */
)
{
        int n;


        for (n = 0; *str; str++, n++) {
                if (fputc(*str, fil) == EOF) return EOF;
        }
        return n;
}




/*-----------------------------------------------------------------------*/
/* Put a formatted string to the file                                    */
/*-----------------------------------------------------------------------*/
int fprintf (
        FIL* fil,                       /* Pointer to the file object */
        const char* str,        /* Pointer to the format string */
        ...                                     /* Optional arguments... */
)
{
        va_list arp;
        UCHAR c, f, r;
        ULONG val;
        char s[16];
        int i, w, res, cc;


        va_start(arp, str);

        for (cc = res = 0; cc != EOF; res += cc) {
                c = *str++;
                if (c == 0) break;                      /* End of string */
                if (c != '%') {                         /* Non escape cahracter */
                        cc = fputc(c, fil);
                        if (cc != EOF) cc = 1;
                        continue;
                }
                w = f = 0;
                c = *str++;
                if (c == '0') {                          /* Flag: '0' padding */
                        f = 1; c = *str++;
                }
                while (c >= '0' && c <= '9') {   /* Precision */
                        w = w * 10 + (c - '0');
                        c = *str++;
                }
                if (c == 'l') {                         /* Prefix: Size is long int */
                        f |= 2; c = *str++;
                }
                if (c == 's') {                         /* Type is string */
                        cc = fputs(va_arg(arp, char*), fil);
                        continue;
                }
                if (c == 'c') {                         /* Type is character */
                        cc = fputc(va_arg(arp, char), fil);
                        if (cc != EOF) cc = 1;
                        continue;
                }
                r = 0;
                if (c == 'd') r = 10;           /* Type is signed decimal */
                if (c == 'u') r = 10;           /* Type is unsigned decimal */
                if (c == 'X') r = 16;           /* Type is unsigned hexdecimal */
                if (r == 0) break;                      /* Unknown type */
                if (f & 2) {                            /* Get the value */
                        val = (ULONG)va_arg(arp, long);
                } else {
                        val = (c == 'd') ? (ULONG)(long)va_arg(arp, int) : (ULONG)va_arg(arp, unsigned int);
                }
                /* Put numeral string */
                if (c == 'd') {
                        if (val >= 0x80000000) {
                                val = 0 - val;
                                f |= 4;
                        }
                }
                i = sizeof(s) - 1; s[i] = 0;
                do {
                        c = (UCHAR)(val % r + '0');
                        if (c > '9') c += 7;
                        s[--i] = c;
                        val /= r;
                } while (i && val);
                if (i && (f & 4)) s[--i] = '-';
                w = sizeof(s) - 1 - w;
                while (i && i > w) s[--i] = (f & 1) ? '0' : ' ';
                cc = fputs(&s[i], fil);
        }

        va_end(arp);
        return (cc == EOF) ? cc : res;
}

#endif /* !_FS_READONLY */
#endif /* _USE_STRFUNC >= 1*/