File handling functions

Functions
cbmimage_file *	cbmimage_file_open_by_name (const char *filename)
	open a file on the cbmimage where the name is known
cbmimage_file *	cbmimage_file_open_by_dir_entry (cbmimage_dir_entry *dir_entry)
	open a file on the cbmimage that has already een enumerated
void	cbmimage_file_close (cbmimage_file *file)
	close a file
int	cbmimage_file_read_next_block (cbmimage_file *file, uint8_t *buffer, size_t buffer_size)
	read a block from the file

Detailed Description

Function Documentation

cbmimage_file_close()

void cbmimage_file_close

(

cbmimage_file *

file

)

close a file

Parameters

[in]

file

pointer to a cbmimage_file that was obtained by a previous cbmimage_file_open_by_name() or cbmimage_file_open_by_dir_entry() call.

Remarks

• Call this function after the proceessing of the file has finished.

cbmimage_file_open_by_dir_entry()

cbmimage_file * cbmimage_file_open_by_dir_entry

(

cbmimage_dir_entry *

dir_entry

)

open a file on the cbmimage that has already een enumerated

Parameters

[in]

dir_entry

ptr to a directory entry for the file that should be opened. That dir_entry must have been the result of a previous cbmimage_dir_get_first() or cbmimage_dir_get_next() call.

Returns

• pointer to a cbmimage_file object than can be used to access the file
• NULL if an error occurred

Remarks

• After the processing of the file has finished, the cbmimage_file must be closed with a call to cbmimage_file_close()
• If the file name is known but the directory entry has not been enumerated, cbmimage_file_open_by_name() can be the better choice.

cbmimage_file_open_by_name()

cbmimage_file * cbmimage_file_open_by_name

(

const char *

filename

)

open a file on the cbmimage where the name is known

Parameters

[in]

filename

pointer to the file name of the file to open on the image.

Returns

• pointer to a cbmimage_file object than can be used to access the file
• NULL if an error occurred

Remarks

• After the processing of the file has finished, the cbmimage_file must be closed with a call to cbmimage_file_close()
• If the file has been already enumated in the directory, cbmimage_file_open_by_dir_entry() will be the better choice.

Todo

implement cbmimage_file_open_by_name()

Todo

Bug

cbmimage_file_open_by_name() not yet implemented

cbmimage_file_read_next_block()

int cbmimage_file_read_next_block	(	cbmimage_file *	file,
		uint8_t *	buffer,
		size_t	buffer_size )

read a block from the file

Parameters

[in]	file	pointer to a cbmimage_file that was obtained by a previous cbmimage_file_open_by_name() or cbmimage_file_open_by_dir_entry() call.
[in,out]	buffer	the buffer where the file contents are written to
[in]	buffer_size	the size of the buffer.

Returns

• > 0: the number of valid byte in the buffer
• = 0: EOF, no more byte are available
• < 0: an error occurred

Remarks

• If you want to read in the whole file, call this function repeatedly until the return value is 0.