/*----------------------------------------------------------------------------/
/  FatFs - FAT file system module  R0.07e                    (C)ChaN, 2009
/-----------------------------------------------------------------------------/
/ FatFs module is a generic FAT file system module for small embedded systems.
/ This is a free software that opened for education, research and commercial
/ developments under license policy of following terms.
/
/  Copyright (C) 2009, ChaN, all right reserved.
/
/ * The FatFs module is a free software and there is NO WARRANTY.
/ * No restriction on use. You can use, modify and redistribute it for
/   personal, non-profit or commercial products 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) partition.
/ 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 algorithm 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 physical 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.
/
/ Apr 01,'09 R0.07  Merged Tiny-FatFs as a buffer configuration option.
/                   Added long file name support.
/                   Added multiple code page support.
/                   Added re-entrancy for multitask operation.
/                   Added auto cluster size selection to f_mkfs().
/                   Added rewind option to f_readdir().
/                   Changed result code of critical errors.
/                   Renamed string functions to avoid name collision.
/ Apr 14,'09 R0.07a Separated out OS dependent code on reentrant cfg.
/                   Added multiple sector size support.
/ Jun 21,'09 R0.07c Fixed f_unlink() can return FR_OK on error.
/                   Fixed wrong cache control in f_lseek().
/                   Added relative path feature.
/                   Added f_chdir() and f_chdrive().
/                   Added proper case conversion to extended char.
/ Nov 03,'09 R0.07e Separated out configuration options from ff.h to ffconf.h.
/                   Fixed f_unlink() fails to remove a sub-dir on _FS_RPATH.
/                   Fixed name matching error on the 13 char boundary.
/                   Added a configuration option, _LFN_UNICODE.
/                   Changed f_readdir() to return the SFN with always upper
/                   case on non-LFN cfg.
/---------------------------------------------------------------------------*/

#include "ff.h"     /* FatFs configurations and declarations */
#include "diskio.h"   /* Declarations of low level disk I/O functions */
#include "includes.h"           // Testing only!

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

   Module Private Definitions

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

#if _FATFS != 0x007E
#error Wrong include file (ff.h).
#endif

#if _FS_REENTRANT
#if _USE_LFN == 1
#error Static LFN work area must not be used in re-entrant configuration.
#endif
#define ENTER_FF(fs)    { if (!lock_fs(fs)) return FR_TIMEOUT; }
#define LEAVE_FF(fs, res) { unlock_fs(fs, res); return res; }

#else
#define ENTER_FF(fs)
#define LEAVE_FF(fs, res) return res

#endif

#define ABORT(fs, res)    { fp->flag |= FA__ERROR; LEAVE_FF(fs, res); }

#ifndef NULL
#define NULL  0
#endif

/* Name status flags */
#define NS      11    /* Offset of name status byte */
#define NS_LOSS   0x01  /* Out of 8.3 format */
#define NS_LFN    0x02  /* Force to create LFN entry */
#define NS_LAST   0x04  /* Last segment */
#define NS_BODY   0x08  /* Lower case flag (body) */
#define NS_EXT    0x10  /* Lower case flag (ext) */
#define NS_DOT    0x20  /* Dot entry */




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

   Private Work Area

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

#if _DRIVES < 1 || _DRIVES > 9
#error Number of drives must be 1-9.
#endif
static
FATFS *FatFs[_DRIVES] __attribute__((section(".xdata")));  /* Pointer to the file system objects (logical drives) */

static
WORD Fsid;        /* File system mount ID */

#if _FS_RPATH
static
BYTE Drive;       /* Current drive */
#endif


#if _USE_LFN == 1 /* LFN with static LFN working buffer */
static
WCHAR LfnBuf[_MAX_LFN + 1];
#define NAMEBUF(sp,lp)  BYTE sp[12]; WCHAR *lp = LfnBuf
#define INITBUF(dj,sp,lp) dj.fn = sp; dj.lfn = lp

#elif _USE_LFN > 1  /* LFN with dynamic LFN working buffer */
#define NAMEBUF(sp,lp)  BYTE sp[12]; WCHAR lbuf[_MAX_LFN + 1], *lp = lbuf
#define INITBUF(dj,sp,lp) dj.fn = sp; dj.lfn = lp

#else       /* No LFN */
#define NAMEBUF(sp,lp)  BYTE sp[12]
#define INITBUF(dj,sp,lp) dj.fn = sp

#endif




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

   Module Private Functions

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


/*-----------------------------------------------------------------------*/
/* String functions                                                      */
/*-----------------------------------------------------------------------*/

/* Copy memory to memory */
static
void mem_cpy (void* dst, const void* src, int cnt) {
  char *d = (char*)dst;
  const char *s = (const char *)src;
  while (cnt--) *d++ = *s++;
}

/* Fill memory */
static
void mem_set (void* dst, int val, int cnt) {
  char *d = (char*)dst;
  while (cnt--) *d++ = (char)val;
}

/* Compare memory to memory */
static
int mem_cmp (const void* dst, const void* src, int cnt) {
  const char *d = (const char *)dst, *s = (const char *)src;
  int r = 0;
  while (cnt-- && (r = *d++ - *s++) == 0) ;
  return r;
}

/* Check if chr is contained in the string */
static
int chk_chr (const char* str, int chr) {
  while (*str && *str != chr) str++;
  return *str;
}



/*-----------------------------------------------------------------------*/
/* Request/Release grant to access the volume                            */
/*-----------------------------------------------------------------------*/
#if _FS_REENTRANT

static
BOOL lock_fs (
  FATFS *fs   /* File system object */
)
{
  return ff_req_grant(fs->sobj);
}


static
void unlock_fs (
  FATFS *fs,    /* File system object */
  FRESULT res   /* Result code to be returned */
)
{
  if (res != FR_NOT_ENABLED &&
    res != FR_INVALID_DRIVE &&
    res != FR_INVALID_OBJECT &&
    res != FR_TIMEOUT) {
    ff_rel_grant(fs->sobj);
  }
}
#endif



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

static
FRESULT move_window (
  FATFS *fs,    /* File system object */
  DWORD sector  /* Sector number to make appearance 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
    if (fs->wflag) {  /* Write back dirty window if needed */
      if (disk_write(fs->drive, fs->win, wsect, 1) != RES_OK)
        return FR_DISK_ERR;
      fs->wflag = 0;
      if (wsect < (fs->fatbase + fs->sects_fat)) {  /* In FAT area */
        BYTE nf;
        for (nf = fs->n_fats; nf > 1; nf--) { /* Reflect the change to all FAT copies */
          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 FR_DISK_ERR;
      fs->winsect = sector;
    }
  }

  return FR_OK;
}




/*-----------------------------------------------------------------------*/
/* Clean-up cached data                                                  */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static
FRESULT sync (  /* FR_OK: successful, FR_DISK_ERR: failed */
  FATFS *fs /* File system object */
)
{
  FRESULT res;


  res = move_window(fs, 0);
  if (res == FR_OK) {
    /* Update FSInfo sector if needed */
    if (fs->fs_type == FS_FAT32 && fs->fsi_flag) {
      fs->winsect = 0;
      mem_set(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;
    }
    /* Make sure that no pending write process in the physical drive */
    if (disk_ioctl(fs->drive, CTRL_SYNC, (void*)NULL) != RES_OK)
      res = FR_DISK_ERR;
  }

  return res;
}
#endif




/*-----------------------------------------------------------------------*/
/* FAT access - Read value of a FAT entry                                */
/*-----------------------------------------------------------------------*/


DWORD get_fat ( /* 0xFFFFFFFF:Disk error, 1:Internal error, Else:Cluster status */
  FATFS *fs,  /* File system object */
  DWORD clst  /* Cluster# to get the link information */
)
{
  UINT wc, bc;
  DWORD fsect;


  if (clst < 2 || clst >= fs->max_clust)  /* Range check */
    return 1;

  fsect = fs->fatbase;
  switch (fs->fs_type) {
  case FS_FAT12 :
    bc = clst; bc += bc / 2;
    if (move_window(fs, fsect + (bc / SS(fs)))) break;
    wc = fs->win[bc & (SS(fs) - 1)]; bc++;
    if (move_window(fs, fsect + (bc / SS(fs)))) break;
    wc |= (WORD)fs->win[bc & (SS(fs) - 1)] << 8;
    return (clst & 1) ? (wc >> 4) : (wc & 0xFFF);

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

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

  return 0xFFFFFFFF;  /* An error occurred at the disk I/O layer */
}




/*-----------------------------------------------------------------------*/
/* FAT access - Change value of a FAT entry                              */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY

FRESULT put_fat (
  FATFS *fs,  /* File system object */
  DWORD clst, /* Cluster# to be changed in range of 2 to fs->max_clust - 1 */
  DWORD val /* New value to mark the cluster */
)
{
  UINT bc;
  BYTE *p;
  DWORD fsect;
  FRESULT res;


  if (clst < 2 || clst >= fs->max_clust) {  /* Range check */
    res = FR_INT_ERR;

  } else {
    fsect = fs->fatbase;
    switch (fs->fs_type) {
    case FS_FAT12 :
      bc = clst; bc += bc / 2;
      res = move_window(fs, fsect + (bc / SS(fs)));
      if (res != FR_OK) break;
      p = &fs->win[bc & (SS(fs) - 1)];
      *p = (clst & 1) ? ((*p & 0x0F) | ((BYTE)val << 4)) : (BYTE)val;
      bc++;
      fs->wflag = 1;
      res = move_window(fs, fsect + (bc / SS(fs)));
      if (res != FR_OK) break;
      p = &fs->win[bc & (SS(fs) - 1)];
      *p = (clst & 1) ? (BYTE)(val >> 4) : ((*p & 0xF0) | ((BYTE)(val >> 8) & 0x0F));
      break;

    case FS_FAT16 :
      res = move_window(fs, fsect + (clst / (SS(fs) / 2)));
      if (res != FR_OK) break;
      ST_WORD(&fs->win[((WORD)clst * 2) & (SS(fs) - 1)], (WORD)val);
      break;

    case FS_FAT32 :
      res = move_window(fs, fsect + (clst / (SS(fs) / 4)));
      if (res != FR_OK) break;
      ST_DWORD(&fs->win[((WORD)clst * 4) & (SS(fs) - 1)], val);
      break;

    default :
      res = FR_INT_ERR;
    }
    fs->wflag = 1;
  }

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




/*-----------------------------------------------------------------------*/
/* FAT handling - Remove a cluster chain                                 */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static
FRESULT remove_chain (
  FATFS *fs,      /* File system object */
  DWORD clst      /* Cluster# to remove a chain from */
)
{
  FRESULT res;
  DWORD nxt;


  if (clst < 2 || clst >= fs->max_clust) {  /* Check the range of cluster# */
    res = FR_INT_ERR;

  } else {
    res = FR_OK;
    while (clst < fs->max_clust) {      /* Not a last link? */
      nxt = get_fat(fs, clst);      /* Get cluster status */
      if (nxt == 0) break;        /* Empty cluster? */
      if (nxt == 1) { res = FR_INT_ERR; break; }  /* Internal error? */
      if (nxt == 0xFFFFFFFF) { res = FR_DISK_ERR; break; }  /* Disk error? */
      res = put_fat(fs, clst, 0);     /* Mark the cluster "empty" */
      if (res != FR_OK) break;
      if (fs->free_clust != 0xFFFFFFFF) { /* Update FSInfo */
        fs->free_clust++;
        fs->fsi_flag = 1;
      }
      clst = nxt; /* Next cluster */
    }
  }

  return res;
}
#endif




/*-----------------------------------------------------------------------*/
/* FAT handling - Stretch or Create a cluster chain                      */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static
DWORD create_chain (  /* 0:No free cluster, 1:Internal error, 0xFFFFFFFF:Disk error, >=2:New cluster# */
  FATFS *fs,      /* File system object */
  DWORD clst      /* Cluster# to stretch. 0 means create a new chain. */
)
{
  DWORD cs, ncl, scl, mcl;


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

  ncl = scl;        /* Start cluster */
  for (;;) {
    ncl++;              /* Next cluster */
    if (ncl >= mcl) {       /* Wrap around */
      ncl = 2;
      if (ncl > scl) return 0;  /* No free cluster */
    }
    cs = get_fat(fs, ncl);      /* Get the cluster status */
    if (cs == 0) break;       /* Found a free cluster */
    if (cs == 0xFFFFFFFF || cs == 1)/* An error occurred */
      return cs;
    if (ncl == scl) return 0;   /* No free cluster */
  }

  if (put_fat(fs, ncl, 0x0FFFFFFF)) /* Mark the new cluster "in use" */
    return 0xFFFFFFFF;
  if (clst != 0) {          /* Link it to the previous one if needed */
    if (put_fat(fs, clst, ncl))
      return 0xFFFFFFFF;
  }

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

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




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


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




/*-----------------------------------------------------------------------*/
/* Directory handling - Seek directory index                             */
/*-----------------------------------------------------------------------*/

static
FRESULT dir_seek (
  DIR *dj,    /* Pointer to directory object */
  WORD idx    /* Directory index number */
)
{
  DWORD clst;
  WORD ic;


  dj->index = idx;
  clst = dj->sclust;
  if (clst == 1 || clst >= dj->fs->max_clust) /* Check start cluster range */
    return FR_INT_ERR;
  if (!clst && dj->fs->fs_type == FS_FAT32) /* Replace cluster# 0 with root cluster# if in FAT32 */
    clst = dj->fs->dirbase;

  if (clst == 0) {  /* Static table */
    dj->clust = clst;
    if (idx >= dj->fs->n_rootdir)   /* Index is out of range */
      return FR_INT_ERR;
    dj->sect = dj->fs->dirbase + idx / (SS(dj->fs) / 32); /* Sector# */
  }
  else {        /* Dynamic table */
    ic = SS(dj->fs) / 32 * dj->fs->csize; /* Entries per cluster */
    while (idx >= ic) { /* Follow cluster chain */
      clst = get_fat(dj->fs, clst);       /* Get next cluster */
      if (clst == 0xFFFFFFFF) return FR_DISK_ERR; /* Disk error */
      if (clst < 2 || clst >= dj->fs->max_clust)  /* Reached to end of table or int error */
        return FR_INT_ERR;
      idx -= ic;
    }
    dj->clust = clst;
    dj->sect = clust2sect(dj->fs, clst) + idx / (SS(dj->fs) / 32);  /* Sector# */
  }

  dj->dir = dj->fs->win + (idx % (SS(dj->fs) / 32)) * 32; /* Ptr to the entry in the sector */

  return FR_OK; /* Seek succeeded */
}




/*-----------------------------------------------------------------------*/
/* Directory handling - Move directory index next                        */
/*-----------------------------------------------------------------------*/

static
FRESULT dir_next (  /* FR_OK:Succeeded, FR_NO_FILE:End of table, FR_DENIED:EOT and could not streach */
  DIR *dj,    /* Pointer to directory object */
  BOOL streach  /* FALSE: Do not stretch table, TRUE: Stretch table if needed */
)
{
  DWORD clst;
  WORD i;


  i = dj->index + 1;
  if (!i || !dj->sect)  /* Report EOT when index has reached 65535 */
    return FR_NO_FILE;

  if (!(i % (SS(dj->fs) / 32))) { /* Sector changed? */
    dj->sect++;         /* Next sector */

    if (dj->clust == 0) { /* Static table */
      if (i >= dj->fs->n_rootdir) /* Report EOT when end of table */
        return FR_NO_FILE;
    }
    else {          /* Dynamic table */
      if (((i / (SS(dj->fs) / 32)) & (dj->fs->csize - 1)) == 0) { /* Cluster changed? */
        clst = get_fat(dj->fs, dj->clust);        /* Get next cluster */
        if (clst <= 1) return FR_INT_ERR;
        if (clst == 0xFFFFFFFF) return FR_DISK_ERR;
        if (clst >= dj->fs->max_clust) {        /* When it reached end of dynamic table */
#if !_FS_READONLY
          BYTE c;
          if (!streach) return FR_NO_FILE;      /* When do not stretch, report EOT */
          clst = create_chain(dj->fs, dj->clust);   /* Stretch cluster chain */
          if (clst == 0) return FR_DENIED;      /* No free cluster */
          if (clst == 1) return FR_INT_ERR;
          if (clst == 0xFFFFFFFF) return FR_DISK_ERR;
          /* Clean-up streached table */
          if (move_window(dj->fs, 0)) return FR_DISK_ERR; /* Flush active window */
          mem_set(dj->fs->win, 0, SS(dj->fs));      /* Clear window buffer */
          dj->fs->winsect = clust2sect(dj->fs, clst); /* Cluster start sector */
          for (c = 0; c < dj->fs->csize; c++) {   /* Fill the new cluster with 0 */
            dj->fs->wflag = 1;
            if (move_window(dj->fs, 0)) return FR_DISK_ERR;
            dj->fs->winsect++;
          }
          dj->fs->winsect -= c;           /* Rewind window address */
#else
          return FR_NO_FILE;      /* Report EOT */
#endif
        }
        dj->clust = clst;       /* Initialize data for new cluster */
        dj->sect = clust2sect(dj->fs, clst);
      }
    }
  }

  dj->index = i;
  dj->dir = dj->fs->win + (i % (SS(dj->fs) / 32)) * 32;

  return FR_OK;
}




/*-----------------------------------------------------------------------*/
/* LFN handling - Test/Pick/Fit an LFN segment from/to directory entry   */
/*-----------------------------------------------------------------------*/
#if _USE_LFN
static
const BYTE LfnOfs[] = {1,3,5,7,9,14,16,18,20,22,24,28,30};  /* Offset of LFN chars in the directory entry */


static
BOOL cmp_lfn (      /* TRUE:Matched, FALSE:Not matched */
  WCHAR *lfnbuf,    /* Pointer to the LFN to be compared */
  BYTE *dir     /* Pointer to the directory entry containing a part of LFN */
)
{
  int i, s;
  WCHAR wc, uc;


  i = ((dir[LDIR_Ord] & 0xBF) - 1) * 13;  /* Get offset in the LFN buffer */
  s = 0; wc = 1;
  do {
    uc = LD_WORD(dir+LfnOfs[s]);  /* Pick an LFN character from the entry */
    if (wc) { /* Last char has not been processed */
      wc = ff_wtoupper(uc);   /* Convert it to upper case */
      if (i >= _MAX_LFN || wc != ff_wtoupper(lfnbuf[i++]))  /* Compare it */
        return FALSE;     /* Not matched */
    } else {
      if (uc != 0xFFFF) return FALSE; /* Check filler */
    }
  } while (++s < 13);       /* Repeat until all chars in the entry are checked */

  if ((dir[LDIR_Ord] & 0x40) && wc && lfnbuf[i])  /* Last segment matched but different length */
    return FALSE;

  return TRUE;          /* The part of LFN matched */
}



static
BOOL pick_lfn (     /* TRUE:Succeeded, FALSE:Buffer overflow */
  WCHAR *lfnbuf,    /* Pointer to the Unicode-LFN buffer */
  BYTE *dir     /* Pointer to the directory entry */
)
{
  int i, s;
  WCHAR wc, uc;


  i = ((dir[LDIR_Ord] & 0x3F) - 1) * 13;  /* Offset in the LFN buffer */

  s = 0; wc = 1;
  do {
    uc = LD_WORD(dir+LfnOfs[s]);      /* Pick an LFN character from the entry */
    if (wc) { /* Last char has not been processed */
      if (i >= _MAX_LFN) return FALSE;  /* Buffer overflow? */
      lfnbuf[i++] = wc = uc;        /* Store it */
    } else {
      if (uc != 0xFFFF) return FALSE;   /* Check filler */
    }
  } while (++s < 13);           /* Read all character in the entry */

  if (dir[LDIR_Ord] & 0x40) {       /* Put terminator if it is the last LFN part */
    if (i >= _MAX_LFN) return FALSE;  /* Buffer overflow? */
    lfnbuf[i] = 0;
  }

  return TRUE;
}


#if !_FS_READONLY
static
void fit_lfn (
  const WCHAR *lfnbuf,  /* Pointer to the LFN buffer */
  BYTE *dir,        /* Pointer to the directory entry */
  BYTE ord,       /* LFN order (1-20) */
  BYTE sum        /* SFN sum */
)
{
  int i, s;
  WCHAR wc;


  dir[LDIR_Chksum] = sum;     /* Set check sum */
  dir[LDIR_Attr] = AM_LFN;    /* Set attribute. LFN entry */
  dir[LDIR_Type] = 0;
  ST_WORD(dir+LDIR_FstClusLO, 0);

  i = (ord - 1) * 13;       /* Get offset in the LFN buffer */
  s = wc = 0;
  do {
    if (wc != 0xFFFF) wc = lfnbuf[i++]; /* Get an effective char */
    ST_WORD(dir+LfnOfs[s], wc); /* Put it */
    if (!wc) wc = 0xFFFF;   /* Padding chars following last char */
  } while (++s < 13);
  if (wc == 0xFFFF || !lfnbuf[i]) ord |= 0x40;  /* Bottom LFN part is the start of LFN sequence */
  dir[LDIR_Ord] = ord;      /* Set the LFN order */
}

#endif
#endif



/*-----------------------------------------------------------------------*/
/* Create numbered name                                                  */
/*-----------------------------------------------------------------------*/
#if _USE_LFN
void gen_numname (
  BYTE *dst,      /* Pointer to generated SFN */
  const BYTE *src,  /* Pointer to source SFN to be modified */
  const WCHAR *lfn, /* Pointer to LFN */
  WORD num      /* Sequence number */
)
{
  char ns[8];
  int i, j;


  mem_cpy(dst, src, 11);

  if (num > 5) {  /* On many collisions, generate a hash number instead of sequential number */
    do num = (num >> 1) + (num << 15) + (WORD)*lfn++; while (*lfn);
  }

  /* itoa */
  i = 7;
  do {
    ns[i--] = (num % 10) + '0';
    num /= 10;
  } while (num);
  ns[i] = '~';

  /* Append the number */
  for (j = 0; j < i && dst[j] != ' '; j++) {
    if (IsDBCS1(dst[j])) {
      if (j == i - 1) break;
      j++;
    }
  }
  do {
    dst[j++] = (i < 8) ? ns[i++] : ' ';
  } while (j < 8);
}
#endif




/*-----------------------------------------------------------------------*/
/* Calculate sum of an SFN                                               */
/*-----------------------------------------------------------------------*/
#if _USE_LFN
static
BYTE sum_sfn (
  const BYTE *dir   /* Ptr to directory entry */
)
{
  BYTE sum = 0;
  int n = 11;

  do sum = (sum >> 1) + (sum << 7) + *dir++; while (--n);
  return sum;
}
#endif




/*-----------------------------------------------------------------------*/
/* Directory handling - Find an object in the directory                  */
/*-----------------------------------------------------------------------*/

static
FRESULT dir_find (
  DIR *dj     /* Pointer to the directory object linked to the file name */
)
{
  FRESULT res;
  BYTE c, *dir;
#if _USE_LFN
  BYTE a, ord, sum;
#endif

  res = dir_seek(dj, 0);      /* Rewind directory object */
  if (res != FR_OK) return res;

#if _USE_LFN
  ord = sum = 0xFF;
#endif
  do {
    res = move_window(dj->fs, dj->sect);
    if (res != FR_OK) break;
    dir = dj->dir;          /* Ptr to the directory entry of current index */
    c = dir[DIR_Name];
    if (c == 0) { res = FR_NO_FILE; break; }  /* Reached to end of table */
#if _USE_LFN  /* LFN configuration */
    a = dir[DIR_Attr] & AM_MASK;
    if (c == 0xE5 || ((a & AM_VOL) && a != AM_LFN)) { /* An entry without valid data */
      ord = 0xFF;
    } else {
      if (a == AM_LFN) {      /* An LFN entry is found */
        if (dj->lfn) {
          if (c & 0x40) {   /* Is it start of LFN sequence? */
            sum = dir[LDIR_Chksum];
            c &= 0xBF; ord = c; /* LFN start order */
            dj->lfn_idx = dj->index;
          }
          /* Check validity of the LFN entry and compare it with given name */
          ord = (c == ord && sum == dir[LDIR_Chksum] && cmp_lfn(dj->lfn, dir)) ? ord - 1 : 0xFF;
        }
      } else {          /* An SFN entry is found */
        if (!ord && sum == sum_sfn(dir)) break; /* LFN matched? */
        ord = 0xFF; dj->lfn_idx = 0xFFFF; /* Reset LFN sequence */
        if (!(dj->fn[NS] & NS_LOSS) && !mem_cmp(dir, dj->fn, 11)) break;  /* SFN matched? */
      }
    }
#else   /* Non LFN configuration */
    if (!(dir[DIR_Attr] & AM_VOL) && !mem_cmp(dir, dj->fn, 11)) /* Is it a valid entry? */
      break;
#endif
    res = dir_next(dj, FALSE);    /* Next entry */
  } while (res == FR_OK);

  return res;
}




/*-----------------------------------------------------------------------*/
/* Read an object from the directory                                     */
/*-----------------------------------------------------------------------*/
#if _FS_MINIMIZE <= 1
static
FRESULT dir_read (
  DIR *dj     /* Pointer to the directory object that pointing the entry to be read */
)
{
  FRESULT res;
  BYTE c, *dir;
#if _USE_LFN
  BYTE a, ord = 0xFF, sum = 0xFF;
#endif

  res = FR_NO_FILE;
  while (dj->sect) {
    res = move_window(dj->fs, dj->sect);
    if (res != FR_OK) break;
    dir = dj->dir;          /* Ptr to the directory entry of current index */
    c = dir[DIR_Name];
    if (c == 0) { res = FR_NO_FILE; break; }  /* Reached to end of table */
#if _USE_LFN  /* LFN configuration */
    a = dir[DIR_Attr] & AM_MASK;
    if (c == 0xE5 || (!_FS_RPATH && c == '.') || ((a & AM_VOL) && a != AM_LFN)) { /* An entry without valid data */
      ord = 0xFF;
    } else {
      if (a == AM_LFN) {      /* An LFN entry is found */
        if (c & 0x40) {     /* Is it start of LFN sequence? */
          sum = dir[LDIR_Chksum];
          c &= 0xBF; ord = c;
          dj->lfn_idx = dj->index;
        }
        /* Check LFN validity and capture it */
        ord = (c == ord && sum == dir[LDIR_Chksum] && pick_lfn(dj->lfn, dir)) ? ord - 1 : 0xFF;
      } else {          /* An SFN entry is found */
        if (ord || sum != sum_sfn(dir)) /* Is there a valid LFN? */
          dj->lfn_idx = 0xFFFF;   /* It has no LFN. */
        break;
      }
    }
#else   /* Non LFN configuration */
    if (c != 0xE5 && (_FS_RPATH || c != '.') && !(dir[DIR_Attr] & AM_VOL))  /* Is it a valid entry? */
      break;
#endif
    res = dir_next(dj, FALSE);        /* Next entry */
    if (res != FR_OK) break;
  }

  if (res != FR_OK) dj->sect = 0;

  return res;
}
#endif



/*-----------------------------------------------------------------------*/
/* Register an object to the directory                                   */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static
FRESULT dir_register (  /* FR_OK:Successful, FR_DENIED:No free entry or too many SFN collision, FR_DISK_ERR:Disk error */
  DIR *dj       /* Target directory with object name to be created */
)
{
  FRESULT res;
  BYTE c, *dir;
#if _USE_LFN  /* LFN configuration */
  WORD n, ne, is;
  BYTE sn[12], *fn, sum;
  WCHAR *lfn;


  fn = dj->fn; lfn = dj->lfn;
  mem_cpy(sn, fn, 12);

  if (_FS_RPATH && (sn[NS] & NS_DOT)) return FR_INVALID_NAME; /* Cannot create dot entry */

  if (sn[NS] & NS_LOSS) {     /* When LFN is out of 8.3 format, generate a numbered name */
    fn[NS] = 0; dj->lfn = NULL;     /* Find only SFN */
    for (n = 1; n < 100; n++) {
      gen_numname(fn, sn, lfn, n);  /* Generate a numbered name */
      res = dir_find(dj);       /* Check if the name collides with existing SFN */
      if (res != FR_OK) break;
    }
    if (n == 100) return FR_DENIED;   /* Abort if too many collisions */
    if (res != FR_NO_FILE) return res;  /* Abort if the result is other than 'not collided' */
    fn[NS] = sn[NS]; dj->lfn = lfn;
  }

  if (sn[NS] & NS_LFN) {      /* When LFN is to be created, reserve reserve an SFN + LFN entries. */
    for (ne = 0; lfn[ne]; ne++) ;
    ne = (ne + 25) / 13;
  } else {            /* Otherwise reserve only an SFN entry. */
    ne = 1;
  }

  /* Reserve contiguous entries */
  res = dir_seek(dj, 0);
  if (res != FR_OK) return res;
  n = is = 0;
  do {
    res = move_window(dj->fs, dj->sect);
    if (res != FR_OK) break;
    c = *dj->dir;       /* Check the entry status */
    if (c == 0xE5 || c == 0) {  /* Is it a blank entry? */
      if (n == 0) is = dj->index; /* First index of the contiguous entry */
      if (++n == ne) break; /* A contiguous entry that required count is found */
    } else {
      n = 0;          /* Not a blank entry. Restart to search */
    }
    res = dir_next(dj, TRUE); /* Next entry with table stretch */
  } while (res == FR_OK);

  if (res == FR_OK && ne > 1) { /* Initialize LFN entry if needed */
    res = dir_seek(dj, is);
    if (res == FR_OK) {
      sum = sum_sfn(dj->fn);  /* Sum of the SFN tied to the LFN */
      ne--;
      do {          /* Store LFN entries in bottom first */
        res = move_window(dj->fs, dj->sect);
        if (res != FR_OK) break;
        fit_lfn(dj->lfn, dj->dir, (BYTE)ne, sum);
        dj->fs->wflag = 1;
        res = dir_next(dj, FALSE);  /* Next entry */
      } while (res == FR_OK && --ne);
    }
  }

#else /* Non LFN configuration */
  res = dir_seek(dj, 0);
  if (res == FR_OK) {
    do {  /* Find a blank entry for the SFN */
      res = move_window(dj->fs, dj->sect);
      if (res != FR_OK) break;
      c = *dj->dir;
      if (c == 0xE5 || c == 0) break; /* Is it a blank entry? */
      res = dir_next(dj, TRUE);   /* Next entry with table streach */
    } while (res == FR_OK);
  }
#endif

  if (res == FR_OK) {   /* Initialize the SFN entry */
    res = move_window(dj->fs, dj->sect);
    if (res == FR_OK) {
      dir = dj->dir;
      mem_set(dir, 0, 32);    /* Clean the entry */
      mem_cpy(dir, dj->fn, 11); /* Put SFN */
      dir[DIR_NTres] = *(dj->fn+NS) & (NS_BODY | NS_EXT); /* Put NT flag */
      dj->fs->wflag = 1;
    }
  }

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




/*-----------------------------------------------------------------------*/
/* Remove an object from the directory                                   */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY && !_FS_MINIMIZE
static
FRESULT dir_remove (  /* FR_OK: Successful, FR_DISK_ERR: A disk error */
  DIR *dj       /* Directory object pointing the entry to be removed */
)
{
  FRESULT res;
#if _USE_LFN  /* LFN configuration */
  WORD i;

  i = dj->index;  /* SFN index */
  res = dir_seek(dj, (WORD)((dj->lfn_idx == 0xFFFF) ? i : dj->lfn_idx));  /* Goto the SFN or top of the LFN entries */
  if (res == FR_OK) {
    do {
      res = move_window(dj->fs, dj->sect);
      if (res != FR_OK) break;
      *dj->dir = 0xE5;      /* Mark the entry "deleted" */
      dj->fs->wflag = 1;
      if (dj->index >= i) break;  /* When reached SFN, all entries of the object has been deleted. */
      res = dir_next(dj, FALSE);  /* Next entry */
    } while (res == FR_OK);
    if (res == FR_NO_FILE) res = FR_INT_ERR;
  }

#else     /* Non LFN configuration */
  res = dir_seek(dj, dj->index);
  if (res == FR_OK) {
    res = move_window(dj->fs, dj->sect);
    if (res == FR_OK) {
      *dj->dir = 0xE5;      /* Mark the entry "deleted" */
      dj->fs->wflag = 1;
    }
  }
#endif

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




/*-----------------------------------------------------------------------*/
/* Pick a segment and create the object name in directory form           */
/*-----------------------------------------------------------------------*/

static
FRESULT create_name (
  DIR *dj,      /* Pointer to the directory object */
  const XCHAR **path  /* Pointer to pointer to the segment in the path string */
)
{
#ifdef _EXCVT
  static const BYTE cvt[] = _EXCVT;
#endif

#if _USE_LFN  /* LFN configuration */
  BYTE b, cf;
  WCHAR w, *lfn;
  int i, ni, si, di;
  const XCHAR *p;

  /* Create LFN in Unicode */
  si = di = 0;
  p = *path;
  lfn = dj->lfn;
  for (;;) {
    w = p[si++];          /* Get a character */
    if (w < ' ' || w == '/' || w == '\\') break;  /* Break on end of segment */
    if (di >= _MAX_LFN)       /* Reject too long name */
      return FR_INVALID_NAME;
#if !_LFN_UNICODE
    w &= 0xFF;
    if (IsDBCS1(w)) {       /* If it is a DBC 1st byte */
      b = p[si++];        /* Get 2nd byte */
      if (!IsDBCS2(b))      /* Reject invalid code for DBC */
        return FR_INVALID_NAME;
      w = (w << 8) + b;
    }
    w = ff_convert(w, 1);     /* Convert OEM to Unicode */
    if (!w) return FR_INVALID_NAME; /* Reject invalid code */
#endif
    if (w < 0x80 && chk_chr("\"*:<>\?|\x7F", w)) /* Reject illegal chars for LFN */
      return FR_INVALID_NAME;
    lfn[di++] = w;          /* Store the Unicode char */
  }
  *path = &p[si];           /* Return pointer to the next segment */
  cf = (w < ' ') ? NS_LAST : 0;   /* Set last segment flag if end of path */
#if _FS_RPATH
  if ((di == 1 && lfn[di - 1] == '.') || /* Is this a dot entry? */
    (di == 2 && lfn[di - 1] == '.' && lfn[di - 2] == '.')) {
    lfn[di] = 0;
    for (i = 0; i < 11; i++)
      dj->fn[i] = (i < di) ? '.' : ' ';
    dj->fn[i] = cf | NS_DOT;    /* This is a dot entry */
    return FR_OK;
  }
#endif
  while (di) {            /* Strip trailing spaces and dots */
    w = lfn[di - 1];
    if (w != ' ' && w != '.') break;
    di--;
  }
  if (!di) return FR_INVALID_NAME;  /* Reject null string */

  lfn[di] = 0;            /* LFN is created */

  /* Create SFN in directory form */
  mem_set(dj->fn, ' ', 11);
  for (si = 0; lfn[si] == ' ' || lfn[si] == '.'; si++) ;  /* Strip leading spaces and dots */
  if (si) cf |= NS_LOSS | NS_LFN;
  while (di && lfn[di - 1] != '.') di--;  /* Find extension (di<=si: no extension) */

  b = i = 0; ni = 8;
  for (;;) {
    w = lfn[si++];          /* Get an LFN char */
    if (!w) break;          /* Break on end of the LFN */
    if (w == ' ' || (w == '.' && si != di)) { /* Remove spaces and dots */
      cf |= NS_LOSS | NS_LFN; continue;
    }

    if (i >= ni || si == di) {    /* Extension or end of SFN */
      if (ni == 11) {       /* Long extension */
        cf |= NS_LOSS | NS_LFN; break;
      }
      if (si != di) cf |= NS_LOSS | NS_LFN; /* Out of 8.3 format */
      if (si > di) break;     /* No extension */
      si = di; i = 8; ni = 11;  /* Enter extension section */
      b <<= 2; continue;
    }

    if (w >= 0x80) {        /* Non ASCII char */
#ifdef _EXCVT
      w = ff_convert(w, 0);   /* Unicode -> OEM code */
      if (w) w = cvt[w - 0x80]; /* Convert extended char to upper (SBCS) */
#else
      w = ff_convert(ff_wtoupper(w), 0);  /* Upper converted Unicode -> OEM code */
#endif
      cf |= NS_LFN;       /* Force create LFN entry */
    }

    if (_DF1S && w >= 0x100) {    /* Double byte char */
      if (i >= ni - 1) {
        cf |= NS_LOSS | NS_LFN; i = ni; continue;
      }
      dj->fn[i++] = (BYTE)(w >> 8);
    } else {            /* Single byte char */
      if (!w || chk_chr("+,;[=]", w)) {   /* Replace illegal chars for SFN */
        w = '_'; cf |= NS_LOSS | NS_LFN;  /* Lossy conversion */
      } else {
        if (IsUpper(w)) {   /* ASCII large capital */
          b |= 2;
        } else {
          if (IsLower(w)) { /* ASCII small capital */
            b |= 1; w -= 0x20;
          }
        }
      }
    }
    dj->fn[i++] = (BYTE)w;
  }

  if (dj->fn[0] == 0xE5) dj->fn[0] = 0x05;  /* If the first char collides with deleted mark, replace it with 0x05 */

  if (ni == 8) b <<= 2;
  if ((b & 0x0C) == 0x0C || (b & 0x03) == 0x03) /* Create LFN entry when there are composite capitals */
    cf |= NS_LFN;
  if (!(cf & NS_LFN)) {           /* When LFN is in 8.3 format without extended char, NT flags are created */
    if ((b & 0x03) == 0x01) cf |= NS_EXT; /* NT flag (Extension has only small capital) */
    if ((b & 0x0C) == 0x04) cf |= NS_BODY;  /* NT flag (Filename has only small capital) */
  }

  dj->fn[NS] = cf;  /* SFN is created */

  return FR_OK;


#else /* Non-LFN configuration */
  BYTE b, c, d, *sfn;
  int ni, si, i;
  const char *p;

  /* Create file name in directory form */
  sfn = dj->fn;
  mem_set(sfn, ' ', 11);
  si = i = b = 0; ni = 8;
  p = *path;
#if _FS_RPATH
  if (p[si] == '.') { /* Is this a dot entry? */
    for (;;) {
      c = p[si++];
      if (c != '.' || si >= 3) break;
      sfn[i++] = c;
    }
    if (c != '/' && c != '\\' && c > ' ') return FR_INVALID_NAME;
    *path = &p[si];                 /* Return pointer to the next segment */
    sfn[NS] = (c <= ' ') ? NS_LAST | NS_DOT : NS_DOT; /* Set last segment flag if end of path */
    return FR_OK;
  }
#endif
  for (;;) {
    c = p[si++];
    if (c <= ' ' || c == '/' || c == '\\') break; /* Break on end of segment */
    if (c == '.' || i >= ni) {
      if (ni != 8 || c != '.') return FR_INVALID_NAME;
      i = 8; ni = 11;
      b <<= 2; continue;
    }
    if (c >= 0x80) {        /* Extended char */
#ifdef _EXCVT
      c = cvt[c - 0x80];      /* Convert extend char (SBCS) */
#else
      b |= 3;           /* Eliminate NT flag if ext char is exist */
#if !_DF1S  /* ASCII only cfg */
      return FR_INVALID_NAME;
#endif
#endif
    }
    if (IsDBCS1(c)) {       /* DBC 1st byte? */
      d = p[si++];        /* Get 2nd byte */
      if (!IsDBCS2(d) || i >= ni - 1) /* Reject invalid DBC */
        return FR_INVALID_NAME;
      sfn[i++] = c;
      sfn[i++] = d;
    } else {            /* Single byte code */
      if (chk_chr(" \"*+,[=]|\x7F", c)) /* Reject illegal chrs for SFN */
        return FR_INVALID_NAME;
      if (IsUpper(c)) {     /* ASCII large capital? */
        b |= 2;
      } else {
        if (IsLower(c)) {   /* ASCII small capital? */
          b |= 1; c -= 0x20;
        }
      }
      sfn[i++] = c;
    }
  }
  *path = &p[si];           /* Return pointer to the next segment */
  c = (c <= ' ') ? NS_LAST : 0;   /* Set last segment flag if end of path */

  if (!i) return FR_INVALID_NAME;   /* Reject null string */
  if (sfn[0] == 0xE5) sfn[0] = 0x05;  /* When first char collides with 0xE5, replace it with 0x05 */

  if (ni == 8) b <<= 2;
  if ((b & 0x03) == 0x01) c |= NS_EXT;  /* NT flag (Extension has only small capital) */
  if ((b & 0x0C) == 0x04) c |= NS_BODY; /* NT flag (Filename has only small capital) */

  sfn[NS] = c;    /* Store NT flag, File name is created */

  return FR_OK;
#endif
}




/*-----------------------------------------------------------------------*/
/* Get file information from directory entry                             */
/*-----------------------------------------------------------------------*/
#if _FS_MINIMIZE <= 1
static
void get_fileinfo (   /* No return code */
  DIR *dj,      /* Pointer to the directory object */
  FILINFO *fno    /* Pointer to the file information to be filled */
)
{
  int i;
  BYTE c, nt, *dir;
  char *p;


  p = fno->fname;
  if (dj->sect) {
    dir = dj->dir;
    nt = dir[DIR_NTres];    /* NT flag */
    for (i = 0; i < 8; i++) { /* Copy name body */
      c = dir[i];
      if (c == ' ') break;
      if (c == 0x05) c = 0xE5;
      if (_USE_LFN && (nt & NS_BODY) && IsUpper(c)) c += 0x20;
      *p++ = c;
    }
    if (dir[8] != ' ') {    /* Copy name extension */
      *p++ = '.';
      for (i = 8; i < 11; i++) {
        c = dir[i];
        if (c == ' ') break;
        if (_USE_LFN && (nt & NS_EXT) && IsUpper(c)) c += 0x20;
        *p++ = c;
      }
    }
    fno->fattrib = dir[DIR_Attr];       /* Attribute */
    fno->fsize = LD_DWORD(dir+DIR_FileSize);  /* Size */
    fno->fdate = LD_WORD(dir+DIR_WrtDate);    /* Date */
    fno->ftime = LD_WORD(dir+DIR_WrtTime);    /* Time */
  }
  *p = 0;

#if _USE_LFN
  if (fno->lfname) {
    XCHAR *tp = fno->lfname;
    WCHAR w, *lfn;

    i = 0;
    if (dj->sect && dj->lfn_idx != 0xFFFF) {/* Get LFN if available */
      lfn = dj->lfn;
      while ((w = *lfn++) != 0) {     /* Get an LFN char */
#if !_LFN_UNICODE
        w = ff_convert(w, 0);     /* Unicode -> OEM conversion */
        if (!w) { i = 0; break; }   /* Could not convert, no LFN */
        if (_DF1S && w >= 0x100)    /* Put 1st byte if it is a DBC */
          tp[i++] = (XCHAR)(w >> 8);
#endif
        if (i >= fno->lfsize - 1) { i = 0; break; } /* Buffer overrun, no LFN */
        tp[i++] = (XCHAR)w;
      }
    }
    tp[i] = 0;  /* Terminator */
  }
#endif
}
#endif /* _FS_MINIMIZE <= 1 */




/*-----------------------------------------------------------------------*/
/* Follow a file path                                                    */
/*-----------------------------------------------------------------------*/

static
FRESULT follow_path ( /* FR_OK(0): successful, !=0: error code */
  DIR *dj,      /* Directory object to return last directory and found object */
  const XCHAR *path /* Full-path string to find a file or directory */
)
{
  FRESULT res;
  BYTE *dir, last;


  while (!_USE_LFN && *path == ' ') path++; /* Skip leading spaces */
#if _FS_RPATH
  if (*path == '/' || *path == '\\') { /* There is a heading separator */
    path++; dj->sclust = 0;   /* Strip it and start from the root dir */
  } else {              /* No heading separator */
    dj->sclust = dj->fs->cdir;  /* Start from the current dir */
  }
#else
  if (*path == '/' || *path == '\\')  /* Strip heading separator if exist */
    path++;
  dj->sclust = 0;           /* Start from the root dir */
#endif

  if ((UINT)*path < ' ') {      /* Null path means the start directory itself */
    res = dir_seek(dj, 0);
    dj->dir = NULL;

  } else {              /* Follow path */
    for (;;) {
      res = create_name(dj, &path); /* Get a segment */
      if (res != FR_OK) break;
      res = dir_find(dj);       /* Find it */
      last = *(dj->fn+NS) & NS_LAST;
      if (res != FR_OK) {       /* Could not find the object */
        if (res == FR_NO_FILE && !last)
          res = FR_NO_PATH;
        break;
      }
      if (last) break;        /* Last segment match. Function completed. */
      dir = dj->dir;          /* There is next segment. Follow the sub directory */
      if (!(dir[DIR_Attr] & AM_DIR)) { /* Cannot follow because it is a file */
        res = FR_NO_PATH; break;
      }
      dj->sclust = ((DWORD)LD_WORD(dir+DIR_FstClusHI) << 16) | LD_WORD(dir+DIR_FstClusLO);
    }
  }

  return res;
}




/*-----------------------------------------------------------------------*/
/* 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, 3: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 3;
  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 ((LD_DWORD(&fs->win[BS_FilSysType]) & 0xFFFFFF) == 0x544146) /* Check "FAT" string */
    return 0;
  if ((LD_DWORD(&fs->win[BS_FilSysType32]) & 0xFFFFFF) == 0x544146)
    return 0;

  return 1;
}




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


FRESULT chk_mounted ( /* FR_OK(0): successful, !=0: any error occurred */
  const XCHAR **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 fmt, *tbl;
  UINT vol;
  DSTATUS stat;
  DWORD bsect, fsize, tsect, mclst;
  const XCHAR *p = *path;
  FATFS *fs;

  /* Get logical drive number from the path name */
  vol = p[0] - '0';       /* Is there a drive number? */
  if (vol <= 9 && p[1] == ':') {  /* Found a drive number, get and strip it */
    p += 2; *path = p;      /* Return pointer to the path name */
  } else {            /* No drive number is given */
#if _FS_RPATH
    vol = Drive;        /* Use current drive */
#else
    vol = 0;          /* Use drive 0 */
#endif
  }

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

  ENTER_FF(fs);         /* Lock file system */

  if (fs->fs_type) {        /* If the logical drive has been mounted */
    stat = disk_status(fs->drive);
    if (!(stat & STA_NOINIT)) { /* and the 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 mounted. Following code attempts to mount the volume */

  fs->fs_type = 0;          /* Clear the file system object */
  fs->drive = (BYTE)LD2PD(vol);   /* 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 _MAX_SS != 512            /* Get disk sector size if needed */
  if (disk_ioctl(fs->drive, GET_SECTOR_SIZE, &SS(fs)) != RES_OK || SS(fs) > _MAX_SS)
    return FR_NO_FILESYSTEM;
#endif
#if !_FS_READONLY
  if (chk_wp && (stat & STA_PROTECT)) /* Check disk write protection if needed */
    return FR_WRITE_PROTECTED;
#endif
  /* Search FAT partition on the drive */
  fmt = check_fs(fs, bsect = 0);    /* Check sector 0 as an SFD format */
  if (fmt == 1) {           /* Not an FAT boot record, it may be partitioned */
    /* Check a partition listed in top of the partition table */
    tbl = &fs->win[MBR_Table + LD2PT(vol) * 16];  /* Partition table */
    if (tbl[4]) {                 /* Is the partition existing? */
      bsect = LD_DWORD(&tbl[8]);          /* Partition offset in LBA */
      fmt = check_fs(fs, bsect);          /* Check the partition */
    }
  }
  if (fmt == 3) return FR_DISK_ERR;
  if (fmt || LD_WORD(fs->win+BPB_BytsPerSec) != SS(fs)) /* No valid FAT partition is found */
    return FR_NO_FILESYSTEM;

  /* Initialize the file system object */
  fsize = LD_WORD(fs->win+BPB_FATSz16);       /* Number of sectors per FAT */
  if (!fsize) fsize = LD_DWORD(fs->win+BPB_FATSz32);
  fs->sects_fat = fsize;
  fs->n_fats = fs->win[BPB_NumFATs];          /* Number of FAT copies */
  fsize *= fs->n_fats;                /* (Number of sectors in FAT area) */
  fs->fatbase = bsect + 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);  /* Number of root directory entries */
  tsect = LD_WORD(fs->win+BPB_TotSec16);        /* Number of sectors on the volume */
  if (!tsect) tsect = LD_DWORD(fs->win+BPB_TotSec32);
  fs->max_clust = mclst = (tsect            /* Last cluster# + 1 (Number of clusters + 2) */
    - LD_WORD(fs->win+BPB_RsvdSecCnt) - fsize - fs->n_rootdir / (SS(fs)/32)
    ) / fs->csize + 2;

  fmt = FS_FAT12;                   /* Determine the FAT sub type */
  if (mclst >= 0xFF7) fmt = FS_FAT16;         /* Number of clusters >= 0xFF5 */
  if (mclst >= 0xFFF7) fmt = FS_FAT32;        /* Number of clusters >= 0xFFF5 */

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

#if !_FS_READONLY
  /* Initialize allocation information */
  fs->free_clust = 0xFFFFFFFF;
  fs->wflag = 0;
  /* Get fsinfo if needed */
  if (fmt == FS_FAT32) {
    fs->fsi_flag = 0;
    fs->fsi_sector = bsect + 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
  fs->fs_type = fmt;    /* FAT sub-type */
  fs->winsect = 0;    /* Invalidate sector cache */
#if _FS_RPATH
  fs->cdir = 0;     /* Current directory (root dir) */
#endif
  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 */
  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;

  ENTER_FF(fs);   /* Lock file system */

  if (disk_status(fs->drive) & STA_NOINIT)
    return FR_NOT_READY;

  return FR_OK;
}




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

   Public Functions

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



/*-----------------------------------------------------------------------*/
/* Mount/Unmount a Logical Drive                                         */
/*-----------------------------------------------------------------------*/

FRESULT f_mount (
  BYTE vol,   /* Logical drive number to be mounted/unmounted */
  FATFS *fs   /* Pointer to new file system object (NULL for unmount)*/
)
{
  FATFS *rfs;


  if (vol >= _DRIVES)       /* Check if the drive number is valid */
    return FR_INVALID_DRIVE;
  rfs = FatFs[vol];       /* Get current fs object */

  if (rfs) {
#if _FS_REENTRANT         /* Discard sync object of the current volume */
    if (!ff_del_syncobj(rfs->sobj)) return FR_INT_ERR;
#endif
    rfs->fs_type = 0;     /* Clear old fs object */
  }

  if (fs) {
    fs->fs_type = 0;      /* Clear new fs object */
#if _FS_REENTRANT         /* Create sync object for the new volume */
    if (!ff_cre_syncobj(vol, &fs->sobj)) return FR_INT_ERR;
#endif
  }
  FatFs[vol] = fs;        /* Register new fs object */

  return FR_OK;
}




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

FRESULT f_open (
  FIL *fp,      /* Pointer to the blank file object */
  const XCHAR *path,  /* Pointer to the file name */
  BYTE mode     /* Access mode and file open mode flags */
)
{
  FRESULT res;
  DIR dj;
  NAMEBUF(sfn, lfn);
  BYTE *dir;


  fp->fs = NULL;    /* Clear file object */
#if !_FS_READONLY
  mode &= (FA_READ | FA_WRITE | FA_CREATE_ALWAYS | FA_OPEN_ALWAYS | FA_CREATE_NEW);
  res = chk_mounted(&path, &dj.fs, (BYTE)(mode & (FA_WRITE | FA_CREATE_ALWAYS | FA_OPEN_ALWAYS | FA_CREATE_NEW)));
#else
  mode &= FA_READ;
  res = chk_mounted(&path, &dj.fs, 0);
#endif
  if (res != FR_OK) LEAVE_FF(dj.fs, res);
  INITBUF(dj, sfn, lfn);
  res = follow_path(&dj, path); /* Follow the file path */

#if !_FS_READONLY
  /* Create or Open a file */
  if (mode & (FA_CREATE_ALWAYS | FA_OPEN_ALWAYS | FA_CREATE_NEW)) {
    DWORD ps, cl;

    if (res != FR_OK) {     /* No file, create new */
      if (res == FR_NO_FILE)  /* There is no file to open, create a new entry */
        res = dir_register(&dj);
      if (res != FR_OK) LEAVE_FF(dj.fs, res);
      mode |= FA_CREATE_ALWAYS;
      dir = dj.dir;     /* Created entry (SFN entry) */
    }
    else {            /* Any object is already existing */
      if (mode & FA_CREATE_NEW)     /* Cannot create new */
        LEAVE_FF(dj.fs, FR_EXIST);
      dir = dj.dir;
      if (!dir || (dir[DIR_Attr] & (AM_RDO | AM_DIR)))  /* Cannot overwrite it (R/O or DIR) */
        LEAVE_FF(dj.fs, FR_DENIED);
      if (mode & FA_CREATE_ALWAYS) {    /* Resize it to zero on over write mode */
        cl = ((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->wflag = 1;
        ps = dj.fs->winsect;      /* Remove the cluster chain */
        if (cl) {
          res = remove_chain(dj.fs, cl);
          if (res) LEAVE_FF(dj.fs, res);
          dj.fs->last_clust = cl - 1; /* Reuse the cluster hole */
        }
        res = move_window(dj.fs, ps);
        if (res != FR_OK) LEAVE_FF(dj.fs, res);
      }
    }
    if (mode & FA_CREATE_ALWAYS) {
      dir[DIR_Attr] = 0;          /* Reset attribute */
      ps = get_fattime();
      ST_DWORD(dir+DIR_CrtTime, ps);    /* Created time */
      dj.fs->wflag = 1;
      mode |= FA__WRITTEN;        /* Set file changed flag */
    }
  }
  /* Open an existing file */
  else {
#endif /* !_FS_READONLY */
    if (res != FR_OK) LEAVE_FF(dj.fs, res); /* Follow failed */
    dir = dj.dir;
    if (!dir || (dir[DIR_Attr] & AM_DIR)) /* It is a directory */
      LEAVE_FF(dj.fs, FR_NO_FILE);
#if !_FS_READONLY
    if ((mode & FA_WRITE) && (dir[DIR_Attr] & AM_RDO)) /* R/O violation */
      LEAVE_FF(dj.fs, FR_DENIED);
  }
  fp->dir_sect = dj.fs->winsect;    /* Pointer to the directory entry */
  fp->dir_ptr = dj.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->dsect = 0;
  fp->fs = dj.fs; fp->id = dj.fs->id; /* Owner file system object of the file */

  LEAVE_FF(dj.fs, 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 clst, sect, remain;
  UINT rcnt, cc;
  BYTE *rbuff = buff;


  *br = 0;  /* Initialize bytes read */

  res = validate(fp->fs, fp->id);         /* Check validity of the object */
  if (res != FR_OK) LEAVE_FF(fp->fs, res);
  if (fp->flag & FA__ERROR)           /* Check abort flag */
    LEAVE_FF(fp->fs, FR_INT_ERR);
  if (!(fp->flag & FA_READ))            /* Check access mode */
    LEAVE_FF(fp->fs, FR_DENIED);
  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? */
        clst = (fp->fptr == 0) ?      /* On the top of the file? */
          fp->org_clust : get_fat(fp->fs, fp->curr_clust);
        if (clst <= 1) ABORT(fp->fs, FR_INT_ERR);
        if (clst == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
        fp->curr_clust = clst;        /* Update current cluster */
        fp->csect = 0;            /* Reset sector offset in the cluster */
      }
      sect = clust2sect(fp->fs, fp->curr_clust);  /* Get current sector */
      if (!sect) ABORT(fp->fs, FR_INT_ERR);
      sect += fp->csect;
      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)
          ABORT(fp->fs, FR_DISK_ERR);
#if !_FS_READONLY && _FS_MINIMIZE <= 2
#if _FS_TINY
        if (fp->fs->wflag && fp->fs->winsect - sect < cc)   /* Replace one of the read sectors with cached data if it contains a dirty sector */
          mem_cpy(rbuff + ((fp->fs->winsect - sect) * SS(fp->fs)), fp->fs->win, SS(fp->fs));
#else
        if ((fp->flag & FA__DIRTY) && fp->dsect - sect < cc)  /* Replace one of the read sectors with cached data if it contains a dirty sector */
          mem_cpy(rbuff + ((fp->dsect - sect) * SS(fp->fs)), fp->buf, SS(fp->fs));
#endif
#endif
        fp->csect += (BYTE)cc;        /* Next sector address in the cluster */
        rcnt = SS(fp->fs) * cc;       /* Number of bytes transferred */
        continue;
      }
#if !_FS_TINY
#if !_FS_READONLY
      if (fp->flag & FA__DIRTY) {     /* Write sector I/O buffer if needed */
        if (disk_write(fp->fs->drive, fp->buf, fp->dsect, 1) != RES_OK)
          ABORT(fp->fs, FR_DISK_ERR);
        fp->flag &= ~FA__DIRTY;
      }
#endif
      if (fp->dsect != sect) {      /* Fill sector buffer with file data */
        if (disk_read(fp->fs->drive, fp->buf, sect, 1) != RES_OK)
          ABORT(fp->fs, FR_DISK_ERR);
      }
#endif
      fp->dsect = sect;
      fp->csect++;              /* Next sector address in the cluster */
    }
    rcnt = SS(fp->fs) - (fp->fptr % SS(fp->fs));  /* Get partial sector data from sector buffer */
    if (rcnt > btr) rcnt = btr;
#if _FS_TINY
    if (move_window(fp->fs, fp->dsect))     /* Move sector window */
      ABORT(fp->fs, FR_DISK_ERR);
    mem_cpy(rbuff, &fp->fs->win[fp->fptr % SS(fp->fs)], rcnt);  /* Pick partial sector */
#else
    mem_cpy(rbuff, &fp->buf[fp->fptr % SS(fp->fs)], rcnt);  /* Pick partial sector */
#endif
  }

  LEAVE_FF(fp->fs, FR_OK);
}




#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 clst, sect;
  UINT wcnt, cc;
  const BYTE *wbuff = buff;


  *bw = 0;  /* Initialize bytes written */

  res = validate(fp->fs, fp->id);         /* Check validity of the object */
  if (res != FR_OK) LEAVE_FF(fp->fs, res);
  if (fp->flag & FA__ERROR)           /* Check abort flag */
    LEAVE_FF(fp->fs, FR_INT_ERR);
  if (!(fp->flag & FA_WRITE))           /* Check access mode */
    LEAVE_FF(fp->fs, FR_DENIED);
  if (fp->fsize + btw < fp->fsize) btw = 0;   /* 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? */
          clst = fp->org_clust;     /* Follow from the origin */
          if (clst == 0)          /* When there is no cluster chain, */
            fp->org_clust = clst = create_chain(fp->fs, 0); /* Create a new cluster chain */
        } else {              /* Middle or end of the file */
          clst = create_chain(fp->fs, fp->curr_clust);      /* Follow or stretch cluster chain */
        }
        if (clst == 0) break;       /* Could not allocate a new cluster (disk full) */
        if (clst == 1) ABORT(fp->fs, FR_INT_ERR);
        if (clst == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
        fp->curr_clust = clst;        /* Update current cluster */
        fp->csect = 0;            /* Reset sector address in the cluster */
      }
#if _FS_TINY
      if (fp->fs->winsect == fp->dsect && move_window(fp->fs, 0)) /* Write back data buffer prior to following direct transfer */
        ABORT(fp->fs, FR_DISK_ERR);
#else
      if (fp->flag & FA__DIRTY) {   /* Write back data buffer prior to following direct transfer */
        if (disk_write(fp->fs->drive, fp->buf, fp->dsect, 1) != RES_OK)
          ABORT(fp->fs, FR_DISK_ERR);
        fp->flag &= ~FA__DIRTY;
      }
#endif
      sect = clust2sect(fp->fs, fp->curr_clust);  /* Get current sector */
      if (!sect) ABORT(fp->fs, FR_INT_ERR);
      sect += fp->csect;
      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)
          ABORT(fp->fs, FR_DISK_ERR);
#if _FS_TINY
        if (fp->fs->winsect - sect < cc) {  /* Refill sector cache if it gets dirty by the direct write */
          mem_cpy(fp->fs->win, wbuff + ((fp->fs->winsect - sect) * SS(fp->fs)), SS(fp->fs));
          fp->fs->wflag = 0;
        }
#else
        if (fp->dsect - sect < cc) {    /* Refill sector cache if it gets dirty by the direct write */
          mem_cpy(fp->buf, wbuff + ((fp->dsect - sect) * SS(fp->fs)), SS(fp->fs));
          fp->flag &= ~FA__DIRTY;
        }
#endif
        fp->csect += (BYTE)cc;        /* Next sector address in the cluster */
        wcnt = SS(fp->fs) * cc;       /* Number of bytes transferred */
        continue;
      }
#if _FS_TINY
      if (fp->fptr >= fp->fsize) {      /* Avoid silly buffer filling at growing edge */
        if (move_window(fp->fs, 0)) ABORT(fp->fs, FR_DISK_ERR);
        fp->fs->winsect = sect;
      }
#else
      if (fp->dsect != sect) {        /* Fill sector buffer with file data */
        if (fp->fptr < fp->fsize &&
          disk_read(fp->fs->drive, fp->buf, sect, 1) != RES_OK)
            ABORT(fp->fs, FR_DISK_ERR);
      }
#endif
      fp->dsect = 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;
#if _FS_TINY
    if (move_window(fp->fs, fp->dsect))     /* Move sector window */
      ABORT(fp->fs, FR_DISK_ERR);
    mem_cpy(&fp->fs->win[fp->fptr % SS(fp->fs)], wbuff, wcnt);  /* Fit partial sector */
    fp->fs->wflag = 1;
#else
    mem_cpy(&fp->buf[fp->fptr % SS(fp->fs)], wbuff, wcnt);  /* Fit partial sector */
    fp->flag |= FA__DIRTY;
#endif
  }

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

  LEAVE_FF(fp->fs, FR_OK);
}




/*-----------------------------------------------------------------------*/
/* 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? */
#if !_FS_TINY /* Write-back dirty buffer */
      if (fp->flag & FA__DIRTY) {
        if (disk_write(fp->fs->drive, fp->buf, fp->dsect, 1) != RES_OK)
          LEAVE_FF(fp->fs, FR_DISK_ERR);
        fp->flag &= ~FA__DIRTY;
      }
#endif
      /* Update the directory entry */
      res = move_window(fp->fs, fp->dir_sect);
      if (res == FR_OK) {
        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 &= ~FA__WRITTEN;
        fp->fs->wflag = 1;
        res = sync(fp->fs);
      }
    }
  }

  LEAVE_FF(fp->fs, res);
}

#endif /* !_FS_READONLY */




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

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


#if _FS_READONLY
    FATFS *fs = fp->fs; /* Patch for FatFs R0.07e Jan 15, 2010 */
  res = validate(fp->fs, fp->id);
  if (res == FR_OK) fp->fs = NULL;
  /* Patch(ed out): LEAVE_FF(fp->fs, res); */
  LEAVE_FF(fs, res); /* Patch for FatFs R0.07e Jan 15, 2010 */
#else
  res = f_sync(fp);
  if (res == FR_OK) fp->fs = NULL;
  return res;
#endif
}




/*-----------------------------------------------------------------------*/
/* Change Current Drive/Directory                                        */
/*-----------------------------------------------------------------------*/

#if _FS_RPATH

FRESULT f_chdrive (
  BYTE drv    /* Drive number */
)
{
  if (drv >= _DRIVES) return FR_INVALID_DRIVE;

  Drive = drv;

  return FR_OK;
}




FRESULT f_chdir (
  const XCHAR *path /* Pointer to the directory path */
)
{
  FRESULT res;
  DIR dj;
  NAMEBUF(sfn, lfn);
  BYTE *dir;


  res = chk_mounted(&path, &dj.fs, 0);
  if (res == FR_OK) {
    INITBUF(dj, sfn, lfn);
    res = follow_path(&dj, path);   /* Follow the file path */
    if (res == FR_OK) {         /* Follow completed */
      dir = dj.dir;         /* Pointer to the entry */
      if (!dir) {
        dj.fs->cdir = 0;      /* No entry (root dir) */
      } else {
        if (dir[DIR_Attr] & AM_DIR) /* Reached to the dir */
          dj.fs->cdir = ((DWORD)LD_WORD(dir+DIR_FstClusHI) << 16) | LD_WORD(dir+DIR_FstClusLO);
        else
          res = FR_NO_PATH;   /* Could not reach the dir (it is a file) */
      }
    }
    if (res == FR_NO_FILE) res = FR_NO_PATH;
  }

  LEAVE_FF(dj.fs, res);
}

#endif



#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 clst, bcs, nsect, ifptr;


  res = validate(fp->fs, fp->id);   /* Check validity of the object */
  if (res != FR_OK) LEAVE_FF(fp->fs, res);
  if (fp->flag & FA__ERROR)     /* Check abort flag */
    LEAVE_FF(fp->fs, FR_INT_ERR);
  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 = nsect = 0; fp->csect = 255;
  if (ofs > 0) {
    bcs = (DWORD)fp->fs->csize * SS(fp->fs);  /* Cluster size (byte) */
    if (ifptr > 0 &&
      (ofs - 1) / bcs >= (ifptr - 1) / bcs) { /* When seek to same or following cluster, */
      fp->fptr = (ifptr - 1) & ~(bcs - 1);  /* start from the current cluster */
      ofs -= fp->fptr;
      clst = fp->curr_clust;
    } else {                  /* When seek to back cluster, */
      clst = fp->org_clust;         /* start from the first cluster */
#if !_FS_READONLY
      if (clst == 0) {            /* If no cluster chain, create a new chain */
        clst = create_chain(fp->fs, 0);
        if (clst == 1) ABORT(fp->fs, FR_INT_ERR);
        if (clst == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
        fp->org_clust = clst;
      }
#endif
      fp->curr_clust = clst;
    }
    if (clst != 0) {
      while (ofs > bcs) {           /* Cluster following loop */
#if !_FS_READONLY
        if (fp->flag & FA_WRITE) {      /* Check if in write mode or not */
          clst = create_chain(fp->fs, clst);  /* Force stretch if in write mode */
          if (clst == 0) {        /* When disk gets full, clip file size */
            ofs = bcs; break;
          }
        } else
#endif
          clst = get_fat(fp->fs, clst); /* Follow cluster chain if not in write mode */
        if (clst == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
        if (clst <= 1 || clst >= fp->fs->max_clust) ABORT(fp->fs, FR_INT_ERR);
        fp->curr_clust = clst;
        fp->fptr += bcs;
        ofs -= bcs;
      }
      fp->fptr += ofs;
      fp->csect = (BYTE)(ofs / SS(fp->fs)); /* Sector offset in the cluster */
      if (ofs % SS(fp->fs)) {
        nsect = clust2sect(fp->fs, clst); /* Current sector */
        if (!nsect) ABORT(fp->fs, FR_INT_ERR);
        nsect += fp->csect;
        fp->csect++;
      }
    }
  }
  if (fp->fptr % SS(fp->fs) && nsect != fp->dsect) {
#if !_FS_TINY
#if !_FS_READONLY
    if (fp->flag & FA__DIRTY) {     /* Write-back dirty buffer if needed */
      if (disk_write(fp->fs->drive, fp->buf, fp->dsect, 1) != RES_OK)
        ABORT(fp->fs, FR_DISK_ERR);
      fp->flag &= ~FA__DIRTY;
    }
#endif
    if (disk_read(fp->fs->drive, fp->buf, nsect, 1) != RES_OK)
      ABORT(fp->fs, FR_DISK_ERR);
#endif
    fp->dsect = nsect;
  }
#if !_FS_READONLY
  if (fp->fptr > fp->fsize) {     /* Set changed flag if the file size is extended */
    fp->fsize = fp->fptr;
    fp->flag |= FA__WRITTEN;
  }
#endif

  LEAVE_FF(fp->fs, res);
}




#if _FS_MINIMIZE <= 1
/*-----------------------------------------------------------------------*/
/* Create a Directroy Object                                             */
/*-----------------------------------------------------------------------*/

FRESULT f_opendir (
  DIR *dj,      /* Pointer to directory object to create */
  const XCHAR *path /* Pointer to the directory path */
)
{
  FRESULT res;
  NAMEBUF(sfn, lfn);
  BYTE *dir;


  res = chk_mounted(&path, &dj->fs, 0);
  if (res == FR_OK) {
    INITBUF((*dj), sfn, lfn);
    res = follow_path(dj, path);      /* Follow the path to the directory */
    if (res == FR_OK) {           /* Follow completed */
      dir = dj->dir;
      if (dir) {              /* It is not the root dir */
        if (dir[DIR_Attr] & AM_DIR) { /* The object is a directory */
          dj->sclust = ((DWORD)LD_WORD(dir+DIR_FstClusHI) << 16) | LD_WORD(dir+DIR_FstClusLO);
        } else {            /* The object is not a directory */
          res = FR_NO_PATH;
        }
      }
      if (res == FR_OK) {
        dj->id = dj->fs->id;
        res = dir_seek(dj, 0);      /* Rewind dir */
      }
    }
    if (res == FR_NO_FILE) res = FR_NO_PATH;
  }

  LEAVE_FF(dj->fs, res);
}




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

FRESULT f_readdir (
  DIR *dj,      /* Pointer to the open directory object */
  FILINFO *fno    /* Pointer to file information to return */
)
{
  FRESULT res;
  NAMEBUF(sfn, lfn);


  res = validate(dj->fs, dj->id);     /* Check validity of the object */
  if (res == FR_OK) {
    INITBUF((*dj), sfn, lfn);
    if (!fno) {
      res = dir_seek(dj, 0);
    } else {
      res = dir_read(dj);
      if (res == FR_NO_FILE) {
        dj->sect = 0;
        res = FR_OK;
      }
      if (res == FR_OK) {       /* A valid entry is found */
        get_fileinfo(dj, fno);    /* Get the object information */
        res = dir_next(dj, FALSE);  /* Increment index for next */
        if (res == FR_NO_FILE) {
          dj->sect = 0;
          res = FR_OK;
        }
      }
    }
  }

  LEAVE_FF(dj->fs, res);
}



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

FRESULT f_stat (
  const XCHAR *path,  /* Pointer to the file path */
  FILINFO *fno    /* Pointer to file information to return */
)
{
  FRESULT res;
  DIR dj;
  NAMEBUF(sfn, lfn);


  res = chk_mounted(&path, &dj.fs, 0);
  if (res == FR_OK) {
    INITBUF(dj, sfn, lfn);
    res = follow_path(&dj, path); /* Follow the file path */
    if (res == FR_OK) {       /* Follow completed */
      if (dj.dir) /* Found an object */
        get_fileinfo(&dj, fno);
      else    /* It is root dir */
        res = FR_INVALID_NAME;
    }
  }

  LEAVE_FF(dj.fs, res);
}



#if !_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Get Number of Free Clusters                                           */
/*-----------------------------------------------------------------------*/

FRESULT f_getfree (
  const XCHAR *path,  /* Pointer to the logical drive number (root dir) */
  DWORD *nclst,   /* 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, clst, sect, stat;
  UINT i;
  BYTE fat, *p;


  /* Get drive number */
  res = chk_mounted(&path, fatfs, 0);
  if (res != FR_OK) LEAVE_FF(*fatfs, res);

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

  /* Get number of free clusters */
  fat = (*fatfs)->fs_type;
  n = 0;
  if (fat == FS_FAT12) {
    clst = 2;
    do {
      stat = get_fat(*fatfs, clst);
      if (stat == 0xFFFFFFFF) LEAVE_FF(*fatfs, FR_DISK_ERR);
      if (stat == 1) LEAVE_FF(*fatfs, FR_INT_ERR);
      if (stat == 0) n++;
    } while (++clst < (*fatfs)->max_clust);
  } else {
    clst = (*fatfs)->max_clust;
    sect = (*fatfs)->fatbase;
    i = 0; p = 0;
    do {
      if (!i) {
        res = move_window(*fatfs, sect++);
        if (res != FR_OK)
          LEAVE_FF(*fatfs, res);
        p = (*fatfs)->win;
        i = SS(*fatfs);
      }
      if (fat == FS_FAT16) {
        if (LD_WORD(p) == 0) n++;
        p += 2; i -= 2;
      } else {
        if ((LD_DWORD(p) & 0x0FFFFFFF) == 0) n++;
        p += 4; i -= 4;
      }
    } while (--clst);
  }
  (*fatfs)->free_clust = n;
  if (fat == FS_FAT32) (*fatfs)->fsi_flag = 1;
  *nclst = n;

  LEAVE_FF(*fatfs, FR_OK);
}




/*-----------------------------------------------------------------------*/
/* 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) LEAVE_FF(fp->fs, res);
  if (fp->flag & FA__ERROR)     /* Check abort flag */
    LEAVE_FF(fp->fs, FR_INT_ERR);
  if (!(fp->flag & FA_WRITE))     /* Check access mode */
    LEAVE_FF(fp->fs, FR_DENIED);

  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 */
      res = remove_chain(fp->fs, fp->org_clust);
      fp->org_clust = 0;
    } else {        /* When truncate a part of the file, remove remaining clusters */
      ncl = get_fat(fp->fs, fp->curr_clust);
      res = FR_OK;
      if (ncl == 0xFFFFFFFF) res = FR_DISK_ERR;
      if (ncl == 1) res = FR_INT_ERR;
      if (res == FR_OK && ncl < fp->fs->max_clust) {
        res = put_fat(fp->fs, fp->curr_clust, 0x0FFFFFFF);
        if (res == FR_OK) res = remove_chain(fp->fs, ncl);
      }
    }
  }
  if (res != FR_OK) fp->flag |= FA__ERROR;

  LEAVE_FF(fp->fs, res);
}




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

FRESULT f_unlink (
  const XCHAR *path   /* Pointer to the file or directory path */
)
{
  FRESULT res;
  DIR dj, sdj;
  NAMEBUF(sfn, lfn);
  BYTE *dir;
  DWORD dclst;


  res = chk_mounted(&path, &dj.fs, 1);
  if (res != FR_OK) LEAVE_FF(dj.fs, res);

  INITBUF(dj, sfn, lfn);
  res = follow_path(&dj, path);     /* Follow the file path */
  if (_FS_RPATH && res == FR_OK && (dj.fn[NS] & NS_DOT))
    res = FR_INVALID_NAME;
  if (res != FR_OK) LEAVE_FF(dj.fs, res); /* Follow failed */

  dir = dj.dir;
  if (!dir)               /* Is it the root directory? */
    LEAVE_FF(dj.fs, FR_INVALID_NAME);
  if (dir[DIR_Attr] & AM_RDO)       /* Is it a R/O object? */
    LEAVE_FF(dj.fs, FR_DENIED);
  dclst = ((DWORD)LD_WORD(dir+DIR_FstClusHI) << 16) | LD_WORD(dir+DIR_FstClusLO);

  if (dir[DIR_Attr] & AM_DIR) {     /* It is a sub-directory */
    if (dclst < 2) LEAVE_FF(dj.fs, FR_INT_ERR);
    mem_cpy(&sdj, &dj, sizeof(DIR));  /* Check if the sub-dir is empty or not */
    sdj.sclust = dclst;
    res = dir_seek(&sdj, 2);
    if (res != FR_OK) LEAVE_FF(dj.fs, res);
    res = dir_read(&sdj);
    if (res == FR_OK) res = FR_DENIED;  /* Not empty sub-dir */
    if (res != FR_NO_FILE) LEAVE_FF(dj.fs, res);
  }

  res = dir_remove(&dj);          /* Remove directory entry */
  if (res == FR_OK) {
    if (dclst)
      res = remove_chain(dj.fs, dclst); /* Remove the cluster chain */
    if (res == FR_OK) res = sync(dj.fs);
  }

  LEAVE_FF(dj.fs, res);
}




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

FRESULT f_mkdir (
  const XCHAR *path   /* Pointer to the directory path */
)
{
  FRESULT res;
  DIR dj;
  NAMEBUF(sfn, lfn);
  BYTE *dir, n;
  DWORD dsect, dclst, pclst, tim;


  res = chk_mounted(&path, &dj.fs, 1);
  if (res != FR_OK) LEAVE_FF(dj.fs, res);

  INITBUF(dj, sfn, lfn);
  res = follow_path(&dj, path);     /* Follow the file path */
  if (res == FR_OK) res = FR_EXIST;   /* Any file or directory is already existing */
  if (_FS_RPATH && res == FR_NO_FILE && (dj.fn[NS] & NS_DOT))
    res = FR_INVALID_NAME;
  if (res != FR_NO_FILE)          /* Any error occurred */
    LEAVE_FF(dj.fs, res);

  dclst = create_chain(dj.fs, 0);     /* Allocate a new cluster for new directory table */
  res = FR_OK;
  if (dclst == 0) res = FR_DENIED;
  if (dclst == 1) res = FR_INT_ERR;
  if (dclst == 0xFFFFFFFF) res = FR_DISK_ERR;
  if (res == FR_OK)
    res = move_window(dj.fs, 0);
  if (res != FR_OK) LEAVE_FF(dj.fs, res);
  dsect = clust2sect(dj.fs, dclst);

  dir = dj.fs->win;           /* Initialize the new directory table */
  mem_set(dir, 0, SS(dj.fs));
  mem_set(dir+DIR_Name, ' ', 8+3);    /* Create "." entry */
  dir[DIR_Name] = '.';
  dir[DIR_Attr] = AM_DIR;
  tim = get_fattime();
  ST_DWORD(dir+DIR_WrtTime, tim);
  ST_WORD(dir+DIR_FstClusLO, dclst);
  ST_WORD(dir+DIR_FstClusHI, dclst >> 16);
  mem_cpy(dir+32, dir, 32);       /* Create ".." entry */
  dir[33] = '.';
  pclst = dj.sclust;
  if (dj.fs->fs_type == FS_FAT32 && pclst == dj.fs->dirbase)
    pclst = 0;
  ST_WORD(dir+32+DIR_FstClusLO, pclst);
  ST_WORD(dir+32+DIR_FstClusHI, pclst >> 16);
  for (n = 0; n < dj.fs->csize; n++) {  /* Write dot entries and clear left sectors */
    dj.fs->winsect = dsect++;
    dj.fs->wflag = 1;
    res = move_window(dj.fs, 0);
    if (res) LEAVE_FF(dj.fs, res);
    mem_set(dir, 0, SS(dj.fs));
  }

  res = dir_register(&dj);
  if (res != FR_OK) {
    remove_chain(dj.fs, dclst);
  } else {
    dir = dj.dir;
    dir[DIR_Attr] = AM_DIR;         /* Attribute */
    ST_DWORD(dir+DIR_WrtTime, tim);     /* Create time */
    ST_WORD(dir+DIR_FstClusLO, dclst);    /* Table start cluster */
    ST_WORD(dir+DIR_FstClusHI, dclst >> 16);
    dj.fs->wflag = 1;
    res = sync(dj.fs);
  }

  LEAVE_FF(dj.fs, res);
}




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

FRESULT f_chmod (
  const XCHAR *path,  /* Pointer to the file path */
  BYTE value,     /* Attribute bits */
  BYTE mask     /* Attribute mask to change */
)
{
  FRESULT res;
  DIR dj;
  NAMEBUF(sfn, lfn);
  BYTE *dir;


  res = chk_mounted(&path, &dj.fs, 1);
  if (res == FR_OK) {
    INITBUF(dj, sfn, lfn);
    res = follow_path(&dj, path);   /* Follow the file path */
    if (_FS_RPATH && res == FR_OK && (dj.fn[NS] & NS_DOT))
      res = FR_INVALID_NAME;
    if (res == FR_OK) {
      dir = dj.dir;
      if (!dir) {           /* Is it a root directory? */
        res = FR_INVALID_NAME;
      } else {            /* File or sub directory */
        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 */
        dj.fs->wflag = 1;
        res = sync(dj.fs);
      }
    }
  }

  LEAVE_FF(dj.fs, res);
}




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

FRESULT f_utime (
  const XCHAR *path,  /* Pointer to the file/directory name */
  const FILINFO *fno  /* Pointer to the time-stamp to be set */
)
{
  FRESULT res;
  DIR dj;
  NAMEBUF(sfn, lfn);
  BYTE *dir;


  res = chk_mounted(&path, &dj.fs, 1);
  if (res == FR_OK) {
    INITBUF(dj, sfn, lfn);
    res = follow_path(&dj, path); /* Follow the file path */
    if (_FS_RPATH && res == FR_OK && (dj.fn[NS] & NS_DOT))
      res = FR_INVALID_NAME;
    if (res == FR_OK) {
      dir = dj.dir;
      if (!dir) {       /* Root directory */
        res = FR_INVALID_NAME;
      } else {        /* File or sub-directory */
        ST_WORD(dir+DIR_WrtTime, fno->ftime);
        ST_WORD(dir+DIR_WrtDate, fno->fdate);
        dj.fs->wflag = 1;
        res = sync(dj.fs);
      }
    }
  }

  LEAVE_FF(dj.fs, res);
}




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

FRESULT f_rename (
  const XCHAR *path_old,  /* Pointer to the old name */
  const XCHAR *path_new /* Pointer to the new name */
)
{
  FRESULT res;
  DIR dj_old, dj_new;
  NAMEBUF(sfn, lfn);
  BYTE buf[21], *dir;
  DWORD dw;


  INITBUF(dj_old, sfn, lfn);
  res = chk_mounted(&path_old, &dj_old.fs, 1);
  if (res == FR_OK) {
    dj_new.fs = dj_old.fs;
    res = follow_path(&dj_old, path_old); /* Check old object */
    if (_FS_RPATH && res == FR_OK && (dj_old.fn[NS] & NS_DOT))
      res = FR_INVALID_NAME;
  }
  if (res != FR_OK) LEAVE_FF(dj_old.fs, res); /* The old object is not found */

  if (!dj_old.dir) LEAVE_FF(dj_old.fs, FR_NO_FILE); /* Is root dir? */
  mem_cpy(buf, dj_old.dir+DIR_Attr, 21);    /* Save the object information */

  mem_cpy(&dj_new, &dj_old, sizeof(DIR));
  res = follow_path(&dj_new, path_new);   /* Check new object */
  if (res == FR_OK) res = FR_EXIST;     /* The new object name is already existing */
  if (res == FR_NO_FILE) {          /* Is it a valid path and no name collision? */
    res = dir_register(&dj_new);      /* Register the new object */
    if (res == FR_OK) {
      dir = dj_new.dir;         /* Copy object information into new entry */
      mem_cpy(dir+13, buf+2, 19);
      dir[DIR_Attr] = buf[0] | AM_ARC;
      dj_old.fs->wflag = 1;
      if (dir[DIR_Attr] & AM_DIR) {   /* Update .. entry in the directory if needed */
        dw = clust2sect(dj_new.fs, (DWORD)LD_WORD(dir+DIR_FstClusHI) | LD_WORD(dir+DIR_FstClusLO));
        if (!dw) {
          res = FR_INT_ERR;
        } else {
          res = move_window(dj_new.fs, dw);
          dir = dj_new.fs->win+32;
          if (res == FR_OK && dir[1] == '.') {
            dw = (dj_new.fs->fs_type == FS_FAT32 && dj_new.sclust == dj_new.fs->dirbase) ? 0 : dj_new.sclust;
            ST_WORD(dir+DIR_FstClusLO, dw);
            ST_WORD(dir+DIR_FstClusHI, dw >> 16);
            dj_new.fs->wflag = 1;
          }
        }
      }
      if (res == FR_OK) {
        res = dir_remove(&dj_old);      /* Remove old entry */
        if (res == FR_OK)
          res = sync(dj_old.fs);
      }
    }
  }

  LEAVE_FF(dj_old.fs, res);
}

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



/*-----------------------------------------------------------------------*/
/* Forward data to the stream directly (Available on only _FS_TINY cfg)  */
/*-----------------------------------------------------------------------*/
#if _USE_FORWARD && _FS_TINY

FRESULT f_forward (
  FIL *fp,            /* Pointer to the file object */
  UINT (*func)(const BYTE*,UINT), /* Pointer to the streaming function */
  UINT btr,           /* Number of bytes to forward */
  UINT *bf            /* Pointer to number of bytes forwarded */
)
{
  FRESULT res;
  DWORD remain, clst, sect;
  UINT rcnt;


  *bf = 0;

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

  remain = fp->fsize - fp->fptr;
  if (btr > remain) btr = (UINT)remain;     /* Truncate btr by remaining bytes */

  for ( ;  btr && (*func)(NULL, 0);       /* Repeat until all data transferred or stream becomes busy */
    fp->fptr += rcnt, *bf += rcnt, btr -= rcnt) {
    if ((fp->fptr % SS(fp->fs)) == 0) {     /* On the sector boundary? */
      if (fp->csect >= fp->fs->csize) {   /* On the cluster boundary? */
        clst = (fp->fptr == 0) ?      /* On the top of the file? */
          fp->org_clust : get_fat(fp->fs, fp->curr_clust);
        if (clst <= 1) ABORT(fp->fs, FR_INT_ERR);
        if (clst == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
        fp->curr_clust = clst;        /* Update current cluster */
        fp->csect = 0;            /* Reset sector address in the cluster */
      }
      fp->csect++;              /* Next sector address in the cluster */
    }
    sect = clust2sect(fp->fs, fp->curr_clust);  /* Get current data sector */
    if (!sect) ABORT(fp->fs, FR_INT_ERR);
    sect += fp->csect - 1;
    if (move_window(fp->fs, sect))        /* Move sector window */
      ABORT(fp->fs, FR_DISK_ERR);
    fp->dsect = sect;
    rcnt = SS(fp->fs) - (WORD)(fp->fptr % SS(fp->fs));  /* Forward data from sector window */
    if (rcnt > btr) rcnt = btr;
    rcnt = (*func)(&fp->fs->win[(WORD)fp->fptr % SS(fp->fs)], rcnt);
    if (!rcnt) ABORT(fp->fs, FR_INT_ERR);
  }

  LEAVE_FF(fp->fs, FR_OK);
}
#endif /* _USE_FORWARD */



#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  131072000UL /* 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] */
)
{
  static const DWORD sstbl[] = { 2048000, 1024000, 512000, 256000, 128000, 64000, 32000, 16000, 8000, 4000,   0 };
  static const WORD cstbl[] =  {   32768,   16384,   8192,   4096,   2048, 16384,  8192,  4096, 2048, 1024, 512 };
  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_clst, d, n;
  WORD as;
  FATFS *fs;
  DSTATUS stat;


  /* Check validity of the parameters */
  if (drv >= _DRIVES) return FR_INVALID_DRIVE;
  if (partition >= 2) 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 _MAX_SS != 512            /* Get disk sector size */
  if (disk_ioctl(drv, GET_SECTOR_SIZE, &SS(fs)) != RES_OK
    || SS(fs) > _MAX_SS)
    return FR_MKFS_ABORTED;
#endif
  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;
  for (d = 512; d <= 32768U && d != allocsize; d <<= 1) ; /* Check validity of the allocation unit size */
  if (d != allocsize) allocsize = 0;
  if (!allocsize) {         /* Auto selection of cluster size */
    d = n_part;
    for (as = SS(fs); as > 512U; as >>= 1) d >>= 1;
    for (n = 0; d < sstbl[n]; n++) ;
    allocsize = cstbl[n];
  }
  if (allocsize < SS(fs)) allocsize = SS(fs);

  allocsize /= SS(fs);    /* Number of sectors per cluster */

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

  /* Determine offset and size of FAT structure */
  switch (fmt) {
  case FS_FAT12:
    n_fat = ((n_clst * 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_clst * 2) + 4 + SS(fs) - 1) / SS(fs);
    n_rsv = 1 + partition;
    n_dir = N_ROOTDIR * 32 / SS(fs);
    break;
  default:
    n_fat = ((n_clst * 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_clst = (n_part - n_rsv - n_fat * N_FATS - n_dir) / allocsize;
  if (   (fmt == FS_FAT16 && n_clst < 0xFF5)
    || (fmt == FS_FAT32 && n_clst < 0xFFF5))
    return FR_MKFS_ABORTED;

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

    mem_set(fs->win, 0, SS(fs));
    tbl = fs->win+MBR_Table;
    ST_DWORD(tbl, 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_DISK_ERR;
    partition = 0xF8;
  } else {
    partition = 0xF0;
  }

  /* Create boot record */
  tbl = fs->win;                /* Clear buffer */
  mem_set(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] = partition;         /* Media descriptor */
  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 sectors per FAT */
    tbl[BS_DrvNum] = 0x80;          /* Drive number */
    tbl[BS_BootSig] = 0x29;         /* Extended boot signature */
    mem_cpy(tbl+BS_VolLab, "NO NAME    FAT     ", 19);  /* Volume label, FAT signature */
  } else {
    ST_DWORD(tbl+BS_VolID32, n);      /* Volume serial number */
    ST_DWORD(tbl+BPB_FATSz32, n_fat);   /* Number of sectors per FAT */
    ST_DWORD(tbl+BPB_RootClus, 2);      /* Root directory cluster (2) */
    ST_WORD(tbl+BPB_FSInfo, 1);       /* FSInfo record offset (bs+1) */
    ST_WORD(tbl+BPB_BkBootSec, 6);      /* Backup boot record offset (bs+6) */
    tbl[BS_DrvNum32] = 0x80;        /* Drive number */
    tbl[BS_BootSig32] = 0x29;       /* Extended boot signature */
    mem_cpy(tbl+BS_VolLab32, "NO NAME    FAT32   ", 19);  /* Volume label, FAT signature */
  }
  ST_WORD(tbl+BS_55AA, 0xAA55);       /* Signature */
  if (SS(fs) > 512U) {
    ST_WORD(tbl+SS(fs)-2, 0xAA55);
  }
  if (disk_write(drv, tbl, b_part+0, 1) != RES_OK)
    return FR_DISK_ERR;
  if (fmt == FS_FAT32)
    disk_write(drv, tbl, b_part+6, 1);

  /* Initialize FAT area */
  for (m = 0; m < N_FATS; m++) {
    mem_set(tbl, 0, SS(fs));    /* 1st sector of the FAT  */
    if (fmt != FS_FAT32) {
      n = (fmt == FS_FAT12) ? 0x00FFFF00 : 0xFFFFFF00;
      n |= partition;
      ST_DWORD(tbl, 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_DISK_ERR;
    mem_set(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_DISK_ERR;
    }
  }

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

#endif /* _USE_MKFS && !_FS_READONLY */




#if _USE_STRFUNC
/*-----------------------------------------------------------------------*/
/* Get a string from the file                                            */
/*-----------------------------------------------------------------------*/
char* f_gets (
  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 : NULL;     /* When no data read (eof or error), return with error. */
}



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


#if _USE_STRFUNC >= 2
  if (chr == '\n') f_putc ('\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 result */
}




/*-----------------------------------------------------------------------*/
/* Put a string to the file                                              */
/*-----------------------------------------------------------------------*/
int f_puts (
  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 (f_putc(*str, fil) == EOF) return EOF;
  }
  return n;
}




/*-----------------------------------------------------------------------*/
/* Put a formatted string to the file                                    */
/*-----------------------------------------------------------------------*/
int f_printf (
  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 character */
      cc = f_putc(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 = f_puts(va_arg(arp, char*), fil);
      continue;
    }
    if (c == 'c') {       /* Type is character */
      cc = f_putc(va_arg(arp, int), 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 = f_puts(&s[i], fil);
  }

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

#endif /* !_FS_READONLY */
#endif /* _USE_STRFUNC */