e:/hudson/workspace/MityDSP MDK Release/trunk/sw/src/fatfs/fatfs_int.c File Reference

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <file.h>
#include <assert.h>
#include <std.h>
#include <clk.h>
#include <errno.h>
#include "fatfs.h"
#include "private/fatfs_int.h"

Defines
#define	MAX_FILENO   21
	hardcoded max 21 FDS. TODO - make dynamic...
#define	SEC_PER_MIN   60
#define	MIN_PER_HOUR   60
#define	HOURS_PER_DAY   24
#define	DAYS_PER_YEAR   365
Functions
int	FAT_Get83Extension (char *apBuffer, char *apBasename, char *apExtension)
	Utility to strip 8.3 file name into basename and extension.
int	FAT_finddirent (const char *apPath, tsFATDevData *apDevData, uint32_t *apDirStartCluster, uint32_t *apDirEntryCluster, uint32_t *apDirEntryInCluster, tsDirEntry *apFileEntry)
	Given a path, locates parent directory cluster information and directory entry information.
int	FAT_createdirent (const char *apNewPath, tsFATDevData *apDevData)
	Given a path to a non-existent entry in a directory, this function creates a new subdirectory at the provided path.
int	FAT_GetNextCluster (tsFATDevData *apDevData, int anCluster)
	Find the Next Cluster In the Chain.
int	FAT_UpdateDirEntry (tsFATFileData *apFileData)
	Updates Directory Data based on current file structure (cached) information.
int	FAT_CountFreeClusters (tsFATDevData *apDevData)
	Count free clusters on the FAT Table.
int	FAT_TruncateCluster (tsFATDevData *apDevData, int anCluster)
	Mark the current cluster as the end of chain, and free all following clusters.
int	FAT_FreeCluster (tsFATDevData *apDevData, int anCluster)
	Free a chain of clusters in the FAT Table.
int	FAT_GetFreeCluster (tsFATDevData *apDevData, int anChainedCluster)
	Find a free cluster on the FAT Table and Mark it used with EOC.
int	FAT_open (const char *apPath, unsigned int anFlags, int anFileno, tsFATDevData *apDevData)
	Attempt to open an existing file or create a new file at the given path.
int	FAT_close (int anFileno)
	Close a file descriptor assocaited with a FAT device.
int	FAT_read (int anFileno, char *apBuffer, unsigned int anCount)
	Read implementation for a FAT filesystem.
int	FAT_write (int anFileno, const char *apBuffer, unsigned int anCount)
	Write implementation for a FAT filesystem.
off_t	FAT_lseek (int anFileno, off_t anOffset, int aeOrigin)
	FAT driver lseek implementation.
int	FAT_unlink (const char *apPath, tsFATDevData *apDevData)
	Delete a file.
int	FAT_rename (const char *apOldPath, const char *apNewPath, tsFATDevData *apDevData)
	Rename a file on a FAT device.
int	FAT_gettime (unsigned int *apYear, unsigned int *apMonth, unsigned int *apDay, unsigned int *apHours, unsigned int *apMinutes, unsigned int *apSeconds, unsigned int *apHundredths)
	Default time callback, used when access to a RTC device is not provided to the FAT filesystem driver.
Variables
tsFATFileData	gpFileData [MAX_FILENO]
	data needed for each file descriptor
static char	FAT_valid_chars [128]

---

Define Documentation

#define MAX_FILENO   21

hardcoded max 21 FDS. TODO - make dynamic...

#define SEC_PER_MIN   60

#define MIN_PER_HOUR   60

#define HOURS_PER_DAY   24

#define DAYS_PER_YEAR   365

---

Function Documentation

int FAT_Get83Extension	(	char *	apBuffer,
		char *	apBasename,
		char *	apExtension
	)

Utility to strip 8.3 file name into basename and extension.

Parameters:

[in]	apBuffer	Name to parse.
[out]	apBasename	Storage for base name
[out]	apExtension	Storage for file extension

Note:

apBasename is assumed to be at least 9 characters long and apExtension is assumed to be at least 4 characters long.

Returns:

Zero for success, or FATFS_INVALID_PATH for invalid 8.3 name.

int FAT_finddirent	(	const char *	apPath,
		tsFATDevData *	apDevData,
		uint32_t *	apDirStartCluster,
		uint32_t *	apDirEntryCluster,
		uint32_t *	apDirEntryInCluster,
		tsDirEntry *	apFileEntry
	)

Given a path, locates parent directory cluster information and directory entry information.

Parameters:

[in]	apPath	pointer to null terminated path to file
[in]	apDevData	FAT interface device data structure
[out]	apDirStartCluster	holder for found parent directory starting cluster. This value is set 0xFFFFFFFF if the path was not found. For FAT16 the dir_start_cluster will be 0x00000000 if the path points to the root directory (which is not in the FAT Data Area).
[out]	apDirEntryCluster	holder for found parent directory cluster containing the entry of the file specified in the path. If the file was not found, then this value is set to 0xFFFFFFF.
[out]	apDirEntryInCluster	the 32 byte index in the dir_entry_cluster containing the location of the file specified. If the file was not found, then this value is set to 0xFFFFFFFF.
[out]	apFileEntry	a copy of the file entry infromation from the parent directory file, this information is not modified if the file is not found.

Returns:

0 on success, FATFS_INVALID_PATH if parent path was invalid, FATFS_FAT_TYPE_NOT_SUPPORTED if an unsupported FAT type was found, FATFS_DEVICE_READ_FAILED is a device read failure occurs, FATFS_DIR_NOT_FOUND if a subdirectory was not found, and FATFS_FILE_NOT_FOUND if file was not located but parent path was OK.

int FAT_createdirent	(	const char *	apNewPath,
		tsFATDevData *	apDevData
	)

Given a path to a non-existent entry in a directory, this function creates a new subdirectory at the provided path.

Parameters:

[in]	apNewPath	pointer to null terminated path to the directory
[in]	apDevData	FAT interface device data structure

Returns:

0 on success, FATFS_INVALID_PATH if parent path was invalid, FATFS_FAT_TYPE_NOT_SUPPORTED if an unsupported FAT type was found, FATFS_DEVICE_READ_FAILED if a device read failure occurs, FATFS_DEVICE_WRITE_FAILED if a device write failure occurs, FATFS_DIR_NOT_FOUND if a subdirectory was not found, or FATFS_FILE_ALREADY_EXISTS if the path points to an existing file.

int FAT_GetNextCluster	(	tsFATDevData *	apDevData,
		int	anCluster
	)

Find the Next Cluster In the Chain.

Parameters:

[in]	apDevData	FAT interface device data structure
[in]	anCluster	Current cluster number

Returns:

0 if no available cluster, FATFS_FAT_TYPE_NOT_SUPPORTED if an unsupported FAT type was found, FATFS_DEVICE_READ_FAILED if a device read failure occurs, otherwise cluster number.

int FAT_UpdateDirEntry

(

tsFATFileData *

apFileData

)

Updates Directory Data based on current file structure (cached) information.

Parameters:

[in]

apFileData

Pointer to file data

Returns:

FATFS_OK on success, FATFS_FAT_TYPE_NOT_SUPPORTED if an unsupported FAT type was found, or FATFS_DEVICE_WRITE_FAILED if a device write failure occurs,

int FAT_CountFreeClusters

(

tsFATDevData *

apDevData

)

Count free clusters on the FAT Table.

Parameters:

[in]

apDevData

Pointer to file system driver

Returns:

The free cluster count, or FATFS_FAT_TYPE_NOT_SUPPORTED if an unsupported FAT type was found, or FATFS_DEVICE_READ_FAILED if a device read failure occurs.

int FAT_TruncateCluster	(	tsFATDevData *	apDevData,
		int	anCluster
	)

Mark the current cluster as the end of chain, and free all following clusters.

Parameters:

[in]	apDevData	Pointer to file system driver
[in]	anCluster	The head of the chain of clusters to truncate.

Returns:

FATFS_OK (0) if successful, or FATFS_FAT_TYPE_NOT_SUPPORTED if an unsupported FAT type was found, or FATFS_DEVICE_READ_FAILED if a device read failure occurs, or FATFS_DEVICE_WRITE_FAILED if a device write failure occurs.

int FAT_FreeCluster	(	tsFATDevData *	apDevData,
		int	anCluster
	)

Free a chain of clusters in the FAT Table.

Parameters:

[in]	apDevData	Pointer to file system driver
[in]	anCluster	The head of the chain of clusters to free.

Returns:

FATFS_OK (0) if successful, or FATFS_FAT_TYPE_NOT_SUPPORTED if an unsupported FAT type was found, or FATFS_DEVICE_READ_FAILED if a device read failure occurs, or FATFS_DEVICE_WRITE_FAILED if a device write failure occurs.

int FAT_GetFreeCluster	(	tsFATDevData *	apDevData,
		int	anChainedCluster
	)

Find a free cluster on the FAT Table and Mark it used with EOC.

Parameters:

[in]	apDevData	Pointer to file system driver
[in]	anChainedCluster	If non-zero, the cluster entry provided will be linked to the newly found free cluster (for file growth)

Returns:

Cluster number allocated (0 if no available cluster), or FATFS_FAT_TYPE_NOT_SUPPORTED if an unsupported FAT type was found, or FATFS_DEVICE_READ_FAILED if a device read failure occurs, or FATFS_DEVICE_WRITE_FAILED if a device write failure occurs.

int FAT_open	(	const char *	apPath,
		unsigned int	anFlags,
		int	anFileno,
		tsFATDevData *	apDevData
	)

Attempt to open an existing file or create a new file at the given path.

Flags indicate actions to be taken.

Parameters:

[in]	apPath	The complete file path.
[in]	anFlags	Flags to control actions (O_WRONLY | O_CREAT | O_TRUNC | O_APPEND)
[in]	anFileno	Internal file descriptor for opened file.
[in]	apDevData	Pointer to file system driver

Returns:

File number if open succeeded, otherwise a negative value to indicate the type of failure.

int FAT_close

(

int

anFileno

)

Close a file descriptor assocaited with a FAT device.

Parameters:

[in]

anFileno

Internal file descriptor for opened file.

Returns:

FATFS_OK on success, negative value on error.

int FAT_read	(	int	anFileno,
		char *	apBuffer,
		unsigned int	anCount
	)

Read implementation for a FAT filesystem.

This routine will up to the specified byte count to the provided buffer from the file referenced by the anFileno file descriptor.

Parameters:

[in]	anFileno	Internal file descriptor for opened file.
[in]	apBuffer	Pointer to data to store read data
[in]	anCount	Number of bytes to read from device

Returns:

Number of bytes read, or a negative number on error.

int FAT_write	(	int	anFileno,
		const char *	apBuffer,
		unsigned int	anCount
	)

Write implementation for a FAT filesystem.

This routine will write count bytes in buffer to the file reference by the anFileno file descriptor.

Parameters:

[in]	anFileno	Internal file descriptor for opened file.
[in]	apBuffer	Pointer to data to write.
[in]	anCount	Number of bytes to write to device

Returns:

Number of bytes written, or a negative number on error.

off_t FAT_lseek	(	int	anFileno,
		off_t	anOffset,
		int	aeOrigin
	)

FAT driver lseek implementation.

Parameters:

[in]	anFileno	Internal file descriptor for opened file.
[in]	anOffset	Byte offset from provided origin.
[in]	aeOrigin	SEEK_SET, SEEK_CUR, or SEEK_END.

Returns:

New file offset, or a negative number on error.

int FAT_unlink	(	const char *	apPath,
		tsFATDevData *	apDevData
	)

Delete a file.

Parameters:

[in]	apPath	Pointer to null terminated path to file
[in]	apDevData	FAT interface device data structure

Returns:

Zero if successful, or a negative number on error.

int FAT_rename	(	const char *	apOldPath,
		const char *	apNewPath,
		tsFATDevData *	apDevData
	)

Rename a file on a FAT device.

Parameters:

[in]	apOldPath	Pointer to null terminated path to current file
[in]	apNewPath	Pointer to null terminated new path for file
[in]	apDevData	FAT interface device data structure

Returns:

Zero if successful, or a negative number on error.

int FAT_gettime	(	unsigned int *	apYear,
		unsigned int *	apMonth,
		unsigned int *	apDay,
		unsigned int *	apHours,
		unsigned int *	apMinutes,
		unsigned int *	apSeconds,
		unsigned int *	apHundredths
	)

Default time callback, used when access to a RTC device is not provided to the FAT filesystem driver.

It uses the system tick timer to compute a date based on the tick count, offset from midnight on January 1, 2000.

Parameters:

[out]	apYear	Location to store RTC year (1980-20??)
[out]	apMonth	Location to store RTC month (1-12)
[out]	apDay	Location to store RTC day (1-31)
[out]	apHours	Location to store RTC hour (0-23)
[out]	apMinutes	Location to store RTC minutes (0-59)
[out]	apSeconds	Location to store RTC seconds (0-59)
[out]	apHundredths	Location to store RTC 1/100's seconds (0-99)

Returns:

Zero for success, -1 for failure.

---

Variable Documentation

tsFATFileData gpFileData[MAX_FILENO]

data needed for each file descriptor

char FAT_valid_chars[128] [static]

Initial value:

{
    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
    0, '!',   0, '#', '$', '%', '&','\'', '(', ')',   0,   0,   0, '-',   0,   0,
  '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',   0,   0,   0,   0,   0,   0,
  '@', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O',
  'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',   0,   0,   0, '^', '_',
  '`', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o',
  'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '{',   0, '}', '~',   0
}