System environment. More...

#include <geogram/basic/environment.h>

Inheritance diagram for GEO::SystemEnvironment:

Protected Member Functions
	~SystemEnvironment () override

bool	set_local_value (const std::string &name, const std::string &value) override
	Sets a variable value locally.

bool	get_local_value (const std::string &name, std::string &value) const override
	Retrieves a variable value locally.

Protected Member Functions inherited from GEO::Environment
	~Environment () override
	Environment destructor.

bool	notify_observers (const std::string &name, const std::string &value, bool recursive)
	Notifies observers.

bool	notify_local_observers (const std::string &name, const std::string &value)
	Notifies local observers.

Protected Member Functions inherited from GEO::Counted
	Counted ()
	Creates a reference counted object.

virtual	~Counted ()
	Destroys a reference counted object.

Additional Inherited Members
Public Member Functions inherited from GEO::Environment
virtual bool	add_environment (Environment *env)
	Adds a child environment.

bool	has_value (const std::string &name) const
	Tests if a variable exists.

virtual bool	get_value (const std::string &name, std::string &value) const
	Retrieves the value of a variable.

std::string	get_value (const std::string &name) const
	Retrieves the value of a variable.

virtual bool	set_value (const std::string &name, const std::string &value)
	Sets a variable value.

virtual Environment *	find_environment (const std::string &name)
	Finds the environment that declares a variable as a local name.

virtual bool	add_observer (const std::string &name, VariableObserver *observer)
	Attaches an observer to a variable.

virtual bool	remove_observer (const std::string &name, VariableObserver *observer)
	Detaches an observer from a variable.

virtual bool	notify_observers (const std::string &name, bool recursive=false)
	Notifies observers.

Public Member Functions inherited from GEO::Counted
void	ref () const
	Increments the reference count.

void	unref () const
	Decrements the reference count.

bool	is_shared () const
	Check if the object is shared.

int	nb_refs () const
	Gets the number of references that point to this object.

Static Public Member Functions inherited from GEO::Environment
static Environment *	instance ()
	Gets the root environment.

static void	terminate ()
	Cleans up the environment.

Static Public Member Functions inherited from GEO::Counted
static void	ref (const Counted *counted)
	Increments the reference count.

static void	unref (const Counted *counted)
	Decrements the reference count.

Detailed Description

System environment.

This class is a specialization of Environment that retrieves the variable values from the system environment, but does not allow to set them.

Definition at line 442 of file environment.h.

Constructor & Destructor Documentation

◆ ~SystemEnvironment()

GEO::SystemEnvironment::~SystemEnvironment ( )

overrideprotected

SystemEnvironment destructor

Member Function Documentation

◆ get_local_value()

bool GEO::SystemEnvironment::get_local_value	(	const std::string &	name,
		std::string &	value
	)		const

overrideprotectedvirtual

Retrieves a variable value locally.

This function is used internally. It searches variable name locally and stores its value in the output string value.

Parameters

[in]	name	the name of the variable
[out]	value	is set the variable value if it was found locally.

Return values

true	if the variable was found
false	if not

Note: This function must be reimplemented in derived custom environments. The value is retrieved from the system environment using the system function getenv().

Implements GEO::Environment.

◆ set_local_value()

bool GEO::SystemEnvironment::set_local_value	(	const std::string &	name,
		const std::string &	value
	)

overrideprotectedvirtual

Sets a variable value locally.

This function is used internally. It sets the variable named name to the given value locally.