bs::shell Class Reference

A simplified shell environment inspired by Bash. More...

#include <shell.h>

Public Member Functions
	shell ()
	Construct bash object.
virtual	~shell ()=default
	Destruct bash object.
const command *	get_command (const std::string &sCommand) const noexcept
	Retrieves a command pointer by its string.
void	set_command (std::unique_ptr< command > &&pCommand)
	Sets a command using a unique pointer. Overwrites previous command.
template<typename CommandT , typename... Args>
void	set_command (Args &&... args)
	Creates and sets a command of type CommandT.
std::unique_ptr< command >	remove_command (const std::string &sCommand)
	Removes a command and returns it.
void	erase_command (const std::string &sCommand)
	Erases a command by its string.
bool	get_stop_on_command_not_found () const noexcept
	Checks if execution stops on command not found.
void	set_stop_on_command_not_found (bool bStopOnCommandNotFound) noexcept
	Sets whether to stop execution on command not found.
virtual void	msg_error_command_not_found (shell_session &oSession, const std::string &sCommand) const
	Displays the error message for “command not found”.
virtual void	msg_error_invalid_function_name (shell_session &oSession, const std::string &sFunction) const
	Displays the error message for “function name invalid”.
virtual void	msg_error_syntax_error (const shell_session &oSession, const shell_parser_exception &oException) const
	Displays the error message for “syntax errors”.

Static Public Member Functions
static std::unique_ptr< shell >	make_default_shell ()
	Construct bash object.
static shell_status	run (std::istream &oCommand, shell_session &oSession)
	Runs a command or script.
static shell_status	run (const std::string &sCommand, shell_session &oSession)
	Runs a command or script.
static shell_status	run (const std::string_view &sCommand, shell_session &oSession)
	Runs a command or script.

Static Public Attributes
static constexpr std::size_t	MAX_DEPTH = SHELL_MAX_DEPTH
	Maximum depth the command interpreter can reach.
static constexpr std::string_view	BASH_ERROR_SYNTAX {"BASH_ERROR_SYNTAX"}
	Message name for bash syntax error.
static constexpr std::string_view	BASH_ERROR_COMMAND_NOT_FOUND {"BASH_ERROR_COMMAND_NOT_FOUND"}
	Message name for bash command not found.
static constexpr std::size_t	DEFAULT_COMMAND_HASH_TABLE_SIZE = 1024
	Default size for the command hash table.

Detailed Description

A simplified shell environment inspired by Bash.

This class provides functionalities for command execution, command management, and error handling. Users can define and control commands while managing how errors are communicated.

The command management methods allow the programmer to strictly control the allowed behaviors, preventing security holes. This enhances the safety and reliability of command execution, ensuring that only authorized commands are executed and that errors are handled gracefully.

It is optimized in the find direction, while the construction is more costly. Uses a fixed size hash table bellow, which is expensive to initialize. You may modify ref shell::DEFAULT_COMMAND_HASH_TABLE_SIZE to change that behavior. In such case do not forget to rebuild the project.

Member Function Documentation

erase_command()

void bs::shell::erase_command

(

const std::string &

sCommand

)

Erases a command by its string.

Parameters

sCommand

The command string to erase.

get_command()

const command * bs::shell::get_command ( const std::string &  sCommand ) const

noexcept

Retrieves a command pointer by its string.

Parameters

sCommand

The command string.

Returns

Pointer to the command, or nullptr if not found.

get_stop_on_command_not_found()

bool bs::shell::get_stop_on_command_not_found ( ) const

noexcept

Checks if execution stops on command not found.

Returns

true if it stops; false otherwise.

make_default_shell()

std::unique_ptr< shell > bs::shell::make_default_shell ( )

static

Construct bash object.

Included commands: Command echo Command eval Command getenv Command getvar Command setenv Command setvar Command seq Command test

msg_error_command_not_found()

void bs::shell::msg_error_command_not_found ( shell_session &  oSession, const std::string &  sCommand  ) const

virtual

Displays the error message for “command not found”.

Can be overwritten with custom behaviour.

Parameters

oSession	Shell session
sCommand	Command not found

msg_error_invalid_function_name()

void bs::shell::msg_error_invalid_function_name ( shell_session &  oSession, const std::string &  sFunction  ) const

virtual

Displays the error message for “function name invalid”.

Can be overwritten with custom behaviour.

Parameters

oSession	Shell session
sFunction	Invalid function name

msg_error_syntax_error()

void bs::shell::msg_error_syntax_error ( const shell_session &  oSession, const shell_parser_exception &  oException  ) const

virtual

Displays the error message for “syntax errors”.

Can be overwritten with custom behaviour.

Parameters

oSession	Shell session
oException	Syntax error

remove_command()

std::unique_ptr< command > bs::shell::remove_command

(

const std::string &

sCommand

)

Removes a command and returns it.

Parameters

sCommand

The command string.

Returns

Unique pointer to the removed command, or nullptr if not found.

run() [1/3]

shell_status bs::shell::run ( const std::string &  sCommand, shell_session &  oSession  )

static

Runs a command or script.

Parameters

sCommand	Command or script to run
oSession	Shell session

Returns

Status code of last executed command

run() [2/3]

shell_status bs::shell::run ( const std::string_view &  sCommand, shell_session &  oSession  )

static

Runs a command or script.

Parameters

sCommand	Command or script to run
oSession	Shell session

Returns

Status code of last executed command

run() [3/3]

shell_status bs::shell::run ( std::istream &  oCommand, shell_session &  oSession  )

static

Runs a command or script.

Parameters

oCommand	Command or script to run
oSession	Shell session

Returns

Status code of last executed command

set_command() [1/2]

template<typename CommandT , typename... Args>

void bs::shell::set_command ( Args &&...  args )

inline

Creates and sets a command of type CommandT.

This template function constructs a command derived from the base class command using the provided arguments and returns a unique pointer to it.

Template Parameters

CommandT

The derived command type.

Parameters

args	Arguments to initialize the command.

Exceptions

std::logic_error

if CommandT is not derived from command.

set_command() [2/2]

void bs::shell::set_command

(

std::unique_ptr< command > &&

pCommand

)

Sets a command using a unique pointer. Overwrites previous command.

Parameters

pCommand

Unique pointer to the command.

set_stop_on_command_not_found()

void bs::shell::set_stop_on_command_not_found ( bool  bStopOnCommandNotFound )

noexcept

Sets whether to stop execution on command not found.

Parameters

bStopOnCommandNotFound

If true, execution stops; if false, it continues.

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The documentation for this class was generated from the following files:

• /home/runner/work/bashspark/bashspark/include/BashSpark/shell.h
• /home/runner/work/bashspark/bashspark/src/BashSpark/shell.cpp