ff.c[2010-03-16-09-03-03].sfb

STM32_fatfs_shell_SDHC.rar

{
	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 Locical 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 streach 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+D