Kernel can run on any binary system platfrom and compile using target platform toolchain e.g. any gcc variant alike. There are APIs require implementation within the concrete target platform project. There are several compile instance profiles available each defines the number of APIs need in implementation. More...

Collaboration diagram for Mandatory APIs called by the Kernel:

Modules
	Kernel lite profile
	Kernel lite variant. Includes a core with basic commands.

	Kernel full profile
	Kernel full variant. Includes a core and all currently available subsystems.

Files
file	console.h
	Console interface used by the Kernel Shell.

file	disk.h
	Disk low level I/O interface called by file I/O subsystem.

file	fat.h
	File system middleware interface called by file I/O subsystem.

file	prompt.h
	System prompt constructor interface used by the Kernel Shell.

Functions
void	con_ln (void)
	Moves cursor to the next line.

void	con_tab (void)
	Inserts a horizontal tab.

void	con_clear (void)
	Clears the console display.

void	con_char (const char code)
	Writes a single character to the console.

void	con_string (const char *str)
	Writes a null-terminated string to the console.

void	con_xy (size_t cx, size_t cy)
	Sets the cursor position.

size_t	con_getx (void)
	Retrieves the current cursor X position.

size_t	con_gety (void)
	Retrieves the current cursor Y position.

void	set_con (void)
	Initializes the console subsystem.

void	disk_io (void)
	Initializes the disk I/O module be a part of a file I/O subsystem.

size_t	get_disks (void)
	Returns the number of detected disks.

void	get_disk (size_t did, disk_t *disk)
	Retrieves disk descriptor by identifier.

void	get_diskInfo (size_t did, char *dsk_info, size_t dsk_infoLen)
	Retrieves human-readable disk information string.

uint8_t	flush_disk (size_t did)
	Flushes pending write operations to disk.

uint8_t	read_disk (void *buffer, size_t did, size_t blck, size_t blocks)
	Reads blocks from disk.

uint8_t	write_disk (void const *buffer, size_t did, size_t blck, size_t blocks)
	Writes blocks to disk.

void	fat_getcwd (char *cwd)
	Retrieves current working directory path.

bool	fat_exists (char const *path)
	Checks whether a file or directory exists.

bool	fat_chdir (char const *cwd)
	Changes current working directory.

bool	fat_mkdir (char const *path)
	Creates a new directory.

bool	fat_unlink (char const *path)
	Removes a file or directory.

bool	fat_mount (char const *path)
	Mounts a FAT filesystem.

bool	fat_unmount (char const *path)
	Unmounts a FAT filesystem.

bool	fat_stat (char const path, filinfo_t fno)
	Retrieves file or directory metadata.

fat_error_code_t	fat_getcode (void)
	Returns last FAT error code.

void	fat_fclose (int fd)
	Closes an open file descriptor.

int	fat_fopen (char const *path, file_access_t mode)
	Opens a file.

size_t	fat_fsize (int fd)
	Returns file size.

size_t	fat_fread (int fd, void *buffer, size_t nread)
	Reads data from file.

size_t	fat_fwrite (int fd, void const *buffer, size_t nwrite)
	Writes data to file.

void	fat_ls (char const path, void const ls_ctx, void(nxt_file)(void const ls_ctx, filinfo_t const *fi))
	Lists directory contents.

void	_shell_prompt (char *prompt, const size_t p_len)
	Generates or retrieves the current shell prompt string.

Variables
size_t	MAX_X
	Maximum horizontal coordinate of the console.

size_t	MAX_Y
	Maximum vertical coordinate of the console.

Detailed Description

Kernel can run on any binary system platfrom and compile using target platform toolchain e.g. any gcc variant alike. There are APIs require implementation within the concrete target platform project. There are several compile instance profiles available each defines the number of APIs need in implementation.

Function Documentation

◆ _shell_prompt()

void _shell_prompt	(	char *	prompt,
		const size_t	p_len
	)

Generates or retrieves the current shell prompt string.

Parameters

[out]	prompt	Output buffer receiving the prompt string.
[in]	p_len	Length of the output buffer in bytes.

Precondition

prompt must not be NULL.
p_len > 0.

Postcondition

prompt contains a null-terminated string on success.
The string is truncated if the buffer is insufficient.

Writes the current shell prompt into the provided buffer. The prompt format is implementation-defined and may include contextual information such as:

Current working directory
User name
System state indicators

The function guarantees null-termination provided p_len > 0.

Side Effects:

None expected (read-only state access).

Warning: The caller is responsible for providing a sufficiently large buffer to avoid truncation.

◆ con_char()

void con_char ( const char code )

Writes a single character to the console.

Parameters

[in] code Character to display.

Writes the specified character at the current cursor position and advances the cursor according to implementation rules.

Note: Control characters may be handled specially.

Side Effects:

Modifies display buffer.
Updates cursor position.

◆ con_clear()

void con_clear ( void )

Clears the console display.

Clears the entire screen buffer and resets the cursor to the origin position (0,0).

Postcondition

Screen buffer is cleared.
Cursor position is (0,0).

Note: When concrete console module doesnt support screen buffer clear (e.g. tty) it can be empty implemented. e.g. void con_clear() { }

Side Effects:: Modifies the entire display buffer.

◆ con_getx()

size_t con_getx ( void )

Retrieves the current cursor X position.

Returns: Current horizontal cursor position.

Returns a value in the range [0, MAX_X - 1].

◆ con_gety()

size_t con_gety ( void )

Retrieves the current cursor Y position.

Returns: Current vertical cursor position.

Returns a value in the range [0, MAX_Y - 1].

◆ con_ln()

void con_ln ( void )

Moves cursor to the next line.

Advances the cursor to the beginning of the next line. Scrolling behavior is implementation-defined if the cursor is currently on the last line.

Postcondition: Cursor X position is reset to 0.

Side Effects:: May trigger screen scrolling.

◆ con_string()

void con_string ( const char * str )

Writes a null-terminated string to the console.

Parameters

[in] str Pointer to null-terminated character string.

Precondition: str must not be NULL.

Writes characters sequentially starting at the current cursor position. Cursor advancement and wrapping behavior are implementation-defined.

Side Effects:

Modifies display buffer.
Updates cursor position.

◆ con_tab()

void con_tab ( void )

Inserts a horizontal tab.

Advances the cursor to the next tab stop. Tab width is implementation-defined.

Side Effects:: Modifies cursor position.

◆ con_xy()

void con_xy	(	size_t	cx,
		size_t	cy
	)

Sets the cursor position.

Parameters

[in]	cx	Horizontal position (column index).
[in]	cy	Vertical position (row index).

Precondition

cx < MAX_X
cy < MAX_Y

Moves the cursor to the specified coordinates. Behavior is undefined if parameters exceed console bounds unless explicitly handled by implementation.

Note: When console doesnt support coordinates navigation (e.g. tty) it can be empty implemented e.g. void con_xy(size_t x, size_t y) { }

Side Effects:: Modifies internal cursor state.

◆ disk_io()

void disk_io ( void )

Initializes the disk I/O module be a part of a file I/O subsystem.

Performs hardware detection, driver initialization, and prepares internal file I/O subsystem disk tables.

Must be called before invoking other disk API functions.

Postcondition: Disk I/O is ready for operations.

Side Effects:

May access hardware.
Initializes internal static state.

◆ fat_chdir()

bool fat_chdir ( char const * cwd )

Changes current working directory.

Parameters

[in] cwd Target directory path.

Return values

true	Directory change successful.
false	Failure (see fat_getcode()).

◆ fat_exists()

bool fat_exists ( char const * path )

Checks whether a file or directory exists.

Parameters

[in] path Path to file or directory.

Returns: true if object exists. false otherwise.

◆ fat_fclose()

void fat_fclose ( int fd )

Closes an open file descriptor.

Parameters

[in] fd File descriptor.

◆ fat_fopen()

int fat_fopen	(	char const *	path,
		file_access_t	mode
	)

Opens a file.

Parameters

[in]	path	File path.
[in]	mode	File access mode flags.

Returns: Non-negative file descriptor on success. Negative value on failure (see fat_getcode()).

◆ fat_fread()

size_t fat_fread	(	int	fd,
		void *	buffer,
		size_t	nread
	)

Reads data from file.

Parameters

[in]	fd	File descriptor.
[out]	buffer	Destination buffer.
[in]	nread	Number of bytes to read.

Returns: Number of bytes actually read.

Precondition: buffer must not be NULL.

◆ fat_fsize()

size_t fat_fsize ( int fd )

Returns file size.

Parameters

[in] fd File descriptor.

Returns: File size in bytes.

◆ fat_fwrite()

size_t fat_fwrite	(	int	fd,
		void const *	buffer,
		size_t	nwrite
	)

Writes data to file.

Parameters

[in]	fd	File descriptor.
[in]	buffer	Source buffer.
[in]	nwrite	Number of bytes to write.

Returns: Number of bytes actually written.

◆ fat_getcode()

fat_error_code_t fat_getcode ( void )

Returns last FAT error code.

Returns: Most recent fat_error_code_t value.

◆ fat_getcwd()

void fat_getcwd ( char * cwd )

Retrieves current working directory path.

Parameters

[out] cwd Output buffer for path string.

Precondition: cwd must not be NULL.

Note: Buffer size must be sufficient for full path.

◆ fat_ls()

void fat_ls	(	char const *	path,
		void const *	ls_ctx,
		void()(void const ls_ctx, filinfo_t const *fi)	nxt_file
	)

Lists directory contents.

Parameters

[in]	path	Directory path.
[in]	ls_ctx	User-defined data context pointer.
[in]	nxt_file	Callback invoked for each directory entry.

Iterates through directory entries and invokes the callback for each discovered file passing user defined data context object pointer

Precondition

nxt_file must not be NULL.

Warning: Callback must not modify filesystem state otherwise a behaviour is undefined.

◆ fat_mkdir()

bool fat_mkdir ( char const * path )

Creates a new directory.

Parameters

[in] path Directory path.

Return values

true	Directory created successfully.
false	Failure (see fat_getcode()).

◆ fat_mount()

bool fat_mount ( char const * path )

Mounts a FAT filesystem.

Parameters

[in] path Mount source (device path).

Return values

true	Mount successful.
false	Mount failed (see fat_getcode()).

Postcondition: Filesystem is ready for access on success.

◆ fat_stat()

bool fat_stat	(	char const *	path,
		filinfo_t *	fno
	)

Retrieves file or directory metadata.

Parameters

[in]	path	Target path.
[out]	fno	Output file information structure.

Return values

true	Information retrieved successfully.
false	Failure (see fat_getcode()).

◆ fat_unlink()

bool fat_unlink ( char const * path )

Removes a file or directory.

Parameters

[in] path Target path.

Return values

true	Removal successful.
false	Failure (see fat_getcode()).

◆ fat_unmount()

bool fat_unmount ( char const * path )

Unmounts a FAT filesystem.

Parameters

[in] path Mount source.

Return values

true	Unmount successful.
false	Unmount failed (see fat_getcode()).

◆ flush_disk()

uint8_t flush_disk ( size_t did )

Flushes pending write operations to disk.

Parameters

[in] did Disk identifier.

Returns: Disk I/O status code.

Return values

DISK_IO_OK	Flush successful.
DISK_INVALID	Invalid disk identifier parameter
DISK_NOT_READY	Disk not initialized.
DISK_IO_ERR	Hardware error occurred.

Side Effects:: May trigger physical media write.

◆ get_disk()

void get_disk	(	size_t	did,
		disk_t *	disk
	)

Retrieves disk descriptor by identifier.

Parameters

[in]	did	Disk identifier.
[out]	disk	Pointer to disk descriptor structure.

Precondition

disk must not be NULL.
did must refer to a valid disk.

Postcondition: disk structure is populated on success.

Warning: Behavior is undefined if disk is NULL.

◆ get_diskInfo()

void get_diskInfo	(	size_t	did,
		char *	dsk_info,
		size_t	dsk_infoLen
	)

Retrieves human-readable disk information string.

Parameters

[in]	did	Disk identifier.
[out]	dsk_info	Output buffer for disk information string.
[in]	dsk_infoLen	Length of output buffer in bytes.

Precondition

dsk_info must not be NULL.
dsk_infoLen > 0.

Writes a null-terminated string describing the disk. Output is truncated if buffer is insufficient.

Side Effects:: Modifies dsk_info buffer.

◆ get_disks()

size_t get_disks ( void )

Returns the number of detected disks.

Returns: Number of available disk devices.

Return values

0	No disks detected or module not initialized.

◆ read_disk()

uint8_t read_disk	(	void *	buffer,
		size_t	did,
		size_t	blck,
		size_t	blocks
	)

Reads blocks from disk.

Parameters

[out]	buffer	Destination buffer.
[in]	did	Disk identifier.
[in]	blck	Starting block index.
[in]	blocks	Number of blocks to read.

Returns: Disk I/O status code.

Return values

DISK_IO_OK	Read successful.
DISK_INVALID	Invalid parameters.
DISK_NOT_READY	Disk not initialized.
DISK_IO_ERR	Hardware read failure.

Precondition

buffer must not be NULL.
blocks > 0.
blck + blocks must not exceed disk capacity.

Side Effects:: Modifies contents of buffer.

◆ set_con()

void set_con ( void )

Initializes the console subsystem.

Performs required hardware or buffer initialization and prepares the console for output operations.

Must be called before using any other console function.

Postcondition

Console is ready for output.
MAX_X and MAX_Y are initialized.

Side Effects:

Initializes internal state.
May access hardware registers or memory-mapped I/O.

◆ write_disk()

uint8_t write_disk	(	void const *	buffer,
		size_t	did,
		size_t	blck,
		size_t	blocks
	)

Writes blocks to disk.

Parameters

[in]	buffer	Source buffer.
[in]	did	Disk identifier.
[in]	blck	Starting block index.
[in]	blocks	Number of blocks to write.

Returns: Disk I/O status code.

Return values

DISK_IO_OK	Write successful.
DISK_WRITE_PROTECT	Media is write-protected.
DISK_INVALID	Invalid parameters.
DISK_NOT_READY	Disk not initialized or media not ready
DISK_IO_ERR	Hardware write failure.

Precondition

buffer must not be NULL.
blocks > 0.
blck + blocks must not exceed disk capacity.

Side Effects:

Modifies disk media.
May trigger physical write operation.

Warning: Data integrity is not guaranteed unless flush_disk() is called after write operations when required.

Variable Documentation

◆ MAX_X

size_t MAX_X

extern

Maximum horizontal coordinate of the console.

Represents the maximum valid X coordinate (column index). Valid cursor X positions range from 0 to (MAX_X - 1).

Note: Value is implementation-defined and must be initialized during console subsystem / module implementation. Must be initialized. When concrete console module doesnt support X coordinate navigation (e.g. tty) it must be initialized as zero

◆ MAX_Y

size_t MAX_Y

extern

Maximum vertical coordinate of the console.

Represents the maximum valid Y coordinate (row index). Valid cursor Y positions range from 0 to (MAX_Y - 1).

Note: Value is implementation-defined and must be initialized during console subsystem / module implementation. Must be initialized When concrete console module doesnt support Y coordinate navigation (e.g. tty) it must be initialized as zero

Modules

Files

Functions

Variables

Detailed Description

Function Documentation

◆ _shell_prompt()

◆ con_char()

◆ con_clear()

◆ con_getx()

◆ con_gety()

◆ con_ln()

◆ con_string()

◆ con_tab()

◆ con_xy()

◆ disk_io()

◆ fat_chdir()

◆ fat_exists()

◆ fat_fclose()

◆ fat_fopen()

◆ fat_fread()

◆ fat_fsize()

◆ fat_fwrite()

◆ fat_getcode()

◆ fat_getcwd()

◆ fat_ls()

◆ fat_mkdir()

◆ fat_mount()

◆ fat_stat()

◆ fat_unlink()

◆ fat_unmount()

◆ flush_disk()

◆ get_disk()

◆ get_diskInfo()

◆ get_disks()

◆ read_disk()

◆ set_con()

◆ write_disk()

Variable Documentation

◆ MAX_X

◆ MAX_Y