PAL file system - platform. This file contains the file system APIs that need to be implemented in the platform layer. More...

#include "pal_fileSystem.h"

Functions
palStatus_t	pal_plat_fsMkdir (const char *pathName)
	This function attempts to create a directory named `pathName`. More...

palStatus_t	pal_plat_fsRmdir (const char *pathName)
	This function deletes a directory. More...

palStatus_t	pal_plat_fsFopen (const char pathName, pal_fsFileMode_t mode, palFileDescriptor_t fd)
	This function opens the file whose name is specified in the parameter `pathName` and associates it with a stream that can be identified in future operations by the `fd` pointer returned. More...

palStatus_t	pal_plat_fsFclose (palFileDescriptor_t *fd)
	This function closes an open file object. More...

palStatus_t	pal_plat_fsFread (palFileDescriptor_t fd, void buffer, size_t numOfBytes, size_t *numberOfBytesRead)
	This function reads an array of bytes from the stream and stores them in the block of memory specified by the buffer. More...

palStatus_t	pal_plat_fsFwrite (palFileDescriptor_t fd, const void buffer, size_t numOfBytes, size_t *numberOfBytesWritten)
	This function starts to write data from the `buffer` to the file at the position pointed by the read/write pointer. More...

palStatus_t	pal_plat_fsFseek (palFileDescriptor_t *fd, int32_t offset, pal_fsOffset_t whence)
	This function moves the file read/write pointer without any read/write operation to the file. More...

palStatus_t	pal_plat_fsFtell (palFileDescriptor_t fd, int32_t pos)
	This function gets the current read/write pointer of a file. More...

palStatus_t	pal_plat_fsUnlink (const char *pathName)
	This function deletes a single file from the file system. More...

palStatus_t	pal_plat_fsRmFiles (const char *pathName)
	This function deletes all files in a folder from the file system (FLAT remove only). More...

palStatus_t	pal_plat_fsCpFolder (const char pathNameSrc, char pathNameDest)
	This function copies all files from a source folder to a destination folder (FLAT copy only). More...

const char *	pal_plat_fsGetDefaultRootFolder (pal_fsStorageID_t dataID)
	This function gets the default value for the root directory. More...

size_t	pal_plat_fsSizeCheck (const char *stringToChk)
	This function finds the length of the string received. More...

palStatus_t	pal_plat_fsMountSystem (void)
	This function sets up the mount point. More...

palStatus_t	pal_plat_fsFormat (pal_fsStorageID_t dataID)
	This function formats the chosen SD partition. More...

Detailed Description

PAL file system - platform. This file contains the file system APIs that need to be implemented in the platform layer.

Note: You need to add the prefix of the ESFS folder root stored in g_esfsRootFolder to all files and folders. To change this, call pal_plat_fsSetEsfsRootFolder().

Function Documentation

palStatus_t pal_plat_fsCpFolder	(	const char *	pathNameSrc,
		char *	pathNameDest
	)

This function copies all files from a source folder to a destination folder (FLAT copy only).

Parameters

[in]	pathNameSrc	A pointer to a null-terminated string that specifies the source folder.
[in]	pathNameDest	A pointer to a null-terminated string that specifies the destination folder. The destination folder MUST exist.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code description palError_t.

Note: Both folders must not be open. If a folder does not exist the function fails.; The process copies one file at a time until all files are copied.; The function does not copy a directory found in the path.

palStatus_t pal_plat_fsFclose ( palFileDescriptor_t * fd )

This function closes an open file object.

Parameters

[in] fd A pointer to the open file object structure to be closed.

Returns: PAL_SUCCESS upon a successful operation. return PAL_FILE_SYSTEM_ERROR - see the error code palError_t.

Note: After the successful execution of the function, the file object is no longer valid and it can be discarded.; In some platforms, this function needs to free the file descriptor memory.

palStatus_t pal_plat_fsFopen	(	const char *	pathName,
		pal_fsFileMode_t	mode,
		palFileDescriptor_t *	fd
	)

This function opens the file whose name is specified in the parameter pathName and associates it with a stream that can be identified in future operations by the fd pointer returned.

Parameters

[out]	fd	A file descriptor for the file entered in the `pathName`.
[in]	*pathName	A pointer to the null-terminated string that specifies the file name to open or create.
[in]	mode	A mode flag that specifies the type of access and open method for the file.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code description palError_t.

Note: The folder path must end with "/".; If necessary, the platform layer allocates memory for the file descriptor. The structure pal_plat_fclose() frees that buffer.; The mode flags sent to this function are normalized to pal_fsFileMode_t and each platform needs to replace them with the proper values.

palStatus_t pal_plat_fsFormat ( pal_fsStorageID_t dataID )

This function formats the chosen SD partition.

Mapping the ID to an actual partition is done in the porting layer.

Parameters

[in] dataID The ID of the partition to be formatted.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code description palError_t.

palStatus_t pal_plat_fsFread	(	palFileDescriptor_t *	fd,
		void *	buffer,
		size_t	numOfBytes,
		size_t *	numberOfBytesRead
	)

This function reads an array of bytes from the stream and stores them in the block of memory specified by the buffer.

The position indicator of the stream is advanced by the total amount of bytes read.

Parameters

[in]	fd	A pointer to the open file object structure.
[in]	buffer	A buffer for storing the read data.
[in]	numOfBytes	The number of bytes to read.
[out]	numberOfBytesRead	The number of bytes read.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code description palError_t.

Note: After successful execution of the function, numberOfBytesRead should be checked to detect end of the file. If numberOfBytesRead is less than numOfBytes, the read/write pointer has reached the end of the file during the read operation or an error has occurred.

palStatus_t pal_plat_fsFseek	(	palFileDescriptor_t *	fd,
		int32_t	offset,
		pal_fsOffset_t	whence
	)

This function moves the file read/write pointer without any read/write operation to the file.

Parameters

[in]	fd	A pointer to the open file object structure.
[in]	offset	The byte offset from `whence` to set the read/write pointer.
[out]	whence	The offset is relative to this.

Note

- The whence options are:

PAL_ERR_FS_SEEKSET - relative to the start of the file.
PAL_ERR_FS_SEEKCUR - relative to the current position indicator.
PAL_ERR_FS_SEEKEND - relative to the end-of-file.

In some systems, there is no whence argument. If you need to implement the whence argument:
PAL_ERR_FS_SEEKEND - The function first finds the length of the file, then subtracts the file length from the position to find the relative path from the beginning.
PAL_ERR_FS_SEEKCUR - The function finds the current stream position and calculates the relative path from the file start.

In both options, fseek() needs to verify that the offset is smaller than the file end or start.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code description palError_t.

palStatus_t pal_plat_fsFtell	(	palFileDescriptor_t *	fd,
		int32_t *	pos
	)

This function gets the current read/write pointer of a file.

Parameters

[in]	fd	A pointer to the open file object structure.
[out]	pos	A pointer to a variable that receives the current file position.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code description palError_t.

palStatus_t pal_plat_fsFwrite	(	palFileDescriptor_t *	fd,
		const void *	buffer,
		size_t	numOfBytes,
		size_t *	numberOfBytesWritten
	)

This function starts to write data from the buffer to the file at the position pointed by the read/write pointer.

Parameters

[in]	fd	A pointer to the open file object structure.
[in]	buffer	A pointer to the data to be written.
[in]	numOfBytes	The number of bytes to write.
[out]	numberOfBytesWritten	The number of bytes written.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code palError_t.

Note: The read/write pointer advances with number of bytes written. After successful execution of the function,; numberOfBytesWritten should be checked to detect if the disk is full. If numberOfBytesWritten is less than numOfBytes, the volume became full during the write operation.

const char* pal_plat_fsGetDefaultRootFolder ( pal_fsStorageID_t dataID )

This function gets the default value for the root directory.

Parameters

[in] dataID - ID of the data to get the root folder for.

Returns: Pointer to the default path.

palStatus_t pal_plat_fsMkdir ( const char * pathName )

This function attempts to create a directory named pathName.

Parameters

[in] *pathName A pointer to the null-terminated string that specifies the directory name to create.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code description palError_t.

Note: To remove a directory use PAL_ERR_FS_rmdir.

Example

palStatus_t ret;
ret = PAL_ERR_FS_mkdir("Dir1");
if(!ret)
{
   //Error
}

palStatus_t pal_plat_fsMountSystem ( void )

This function sets up the mount point.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code description palError_t.

palStatus_t pal_plat_fsRmdir ( const char * pathName )

This function deletes a directory.

Parameters

[in] *pathName A pointer to the null-terminated string that specifies the name of the directory to be deleted.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code description palError_t.

Note: The directory to be deleted must be Empty and closed. The folder path must end with "/". If given .., the function changes the root directory to one directory down and deletes the working directory.

palStatus_t pal_plat_fsRmFiles ( const char * pathName )

This function deletes all files in a folder from the file system (FLAT remove only).

Parameters

[in] pathName A pointer to a null-terminated string that specifies the folder.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code description palError_t.

Note: The folder must not be open and the folder path must end with /.; The process deletes one file at a time by calling pal_plat_fsUnlink until all files are removed.; The function does not remove a directory found in the path.

size_t pal_plat_fsSizeCheck ( const char * stringToChk )

This function finds the length of the string received.

Parameters

[in] stringToChk A pointer to the string received with a null terminator.

Returns: The size of the string.

palStatus_t pal_plat_fsUnlink ( const char * pathName )

This function deletes a single file from the file system.

Parameters

[in] pathName A pointer to a null-terminated string that specifies the file to be removed.

Returns: PAL_SUCCESS upon a successful operation.; PAL_FILE_SYSTEM_ERROR - see the error code description palError_t.

Note: The file must not be open.

Documentation

Functions

Detailed Description

Function Documentation