env.c File Reference

Functions for setting and getting environment variables. More...

#include "config.h"
#include <stdlib.h>
#include <wchar.h>
#include <string.h>
#include <stdio.h>
#include <locale.h>
#include <unistd.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <pwd.h>
#include <ncurses.h>
#include <termio.h>
#include <term.h>
#include <libintl.h>
#include <errno.h>
#include "fallback.h"
#include "util.h"
#include "wutil.h"
#include "proc.h"
#include "common.h"
#include "env.h"
#include "sanity.h"
#include "expand.h"
#include "history.h"
#include "reader.h"
#include "parser.h"
#include "env_universal.h"
#include "input_common.h"
#include "event.h"
#include "path.h"
#include "halloc.h"
#include "halloc_util.h"
#include "complete.h"

Data Structures

struct env_node

Struct representing one level in the function variable stack. More...

struct var_entry

A variable entry. More...

Defines

#define FISHD_CMD L"fishd ^/tmp/fishd.log.%s"

Command used to start fishd.

#define ENV_NULL L"\x1d"

Value denoting a null string.

Typedefs

typedef struct env_node env_node_t

Struct representing one level in the function variable stack.

typedef struct var_entry var_entry_t

A variable entry.

Functions

static void clear_hash_entry (void *key, void *data)

Free hash key and hash value.

static void start_fishd ()

When fishd isn't started, this function is provided to env_universal as a callback, it tries to start up fishd.

static mode_t get_umask ()

Return the current umask value.

static int is_locale (const wchar_t *key)

Checks if the specified variable is a locale variable.

static void handle_locale ()

Properly sets all locale information.

static void universal_callback (int type, const wchar_t *name, const wchar_t *val)

Universal variable callback function.

static void setup_path ()

Make sure the PATH variable contains the essaential directories.

int env_set_pwd ()

Update the PWD variable directory.

static void env_set_defaults ()

Set up default values for various variables if not defined.

void env_init ()

Initialize environment variable data.

void env_destroy ()

Destroy environment variable data.

static env_node_t * env_get_node (const wchar_t *key)

Search all visible scopes in order for the specified key.

int env_set (const wchar_t *key, const wchar_t *val, int var_mode)

Set the value of the environment variable whose name matches key to val.

static int try_remove (env_node_t *n, const wchar_t *key, int var_mode)

Attempt to remove/free the specified key/value pair from the specified hash table.

int env_remove (const wchar_t *key, int var_mode)

Remove environemnt variable.

wchar_t * env_get (const wchar_t *key)

Return the value of the variable with the specified name.

int env_exist (const wchar_t *key, int mode)

Returns 1 if the specified key exists.

static int local_scope_exports (env_node_t *n)

Returns true if the specified scope or any non-shadowed non-global subscopes contain an exported variable.

void env_push (int new_scope)

Push the variable stack.

void env_pop ()

Pop the variable stack.

static void add_key_to_hash (void *key, void *data, void *aux)

Function used with hash_foreach to insert keys of one table into another.

static void add_to_hash (void *k, void *aux)

Add key to hashtable.

static void add_key_to_list (void *key, void *val, void *aux)

Add key to list.

void env_get_names (array_list_t *l, int flags)

Insert all variable names into l.

static void export_func1 (void *k, void *v, void *aux)

Function used by env_export_arr to iterate over hashtable of variables.

static void get_exported (env_node_t *n, hash_table_t *h)

Get list of all exported variables.

static void export_func2 (void *k, void *v, void *aux)

Function used by env_export_arr to iterate over hashtable of variables.

char ** env_export_arr (int recalc)

Returns an array containing all exported variables in a format suitable for execv.

Variables

char ** environ

At init, we read all the environment variables from this array.

char ** __environ

This should be the same thing as environ, but it is possible only one of the two work.

static env_node_t * top = 0

Top node on the function stack.

static env_node_t * global_env = 0

Bottom node on the function stack.

static hash_table_t * global

Table for global variables.

static hash_table_t env_read_only

Table of variables that may not be set using the set command.

static hash_table_t env_electric

Table of variables whose value is dynamically calculated, such as umask, status, etc.

static char ** export_arr = 0

Exported variable array used by execv.

static buffer_t export_buffer

Buffer used for storing string contents for export_arr.

static int has_changed = 1

Flag for checking if we need to regenerate the exported variable array.

static string_buffer_t dyn_var

This stringbuffer is used to store the value of dynamically generated variables, such as history.

static int get_names_show_exported

Variable used by env_get_names to communicate auxiliary information to add_key_to_hash.

static int get_names_show_unexported

Variable used by env_get_names to communicate auxiliary information to add_key_to_hash.

static const wchar_t * locale_variable []

List of all locale variable names.

Detailed Description

Functions for setting and getting environment variables.

Typedef Documentation

typedef struct var_entry var_entry_t

A variable entry.

Stores the value of a variable and whether it should be exported. Obviously, it needs to be allocated large enough to fit the value string.

Function Documentation

int env_exist	(	const wchar_t *	key,
		int	mode
	)

Returns 1 if the specified key exists.

This can't be reliably done using env_get, since env_get returns null for 0-element arrays

Parameters:

	key	The name of the variable to remove
	mode	the scope to search in. All scopes are searched if unset

References CHECK, env_node::env, ENV_GLOBAL, ENV_LOCAL, ENV_UNIVERSAL, env_universal_barrier(), hash_get(), env_node::new_scope, env_node::next, and proc_had_barrier.

Referenced by builtin_set().

wchar_t* env_get ( const wchar_t * key )

Return the value of the variable with the specified name.

Returns 0 if the key does not exist. The returned string should not be modified or freed. The returned string is only guaranteed to be valid until the next call to env_get(), env_set(), env_push() or env_pop() takes place.

References ARRAY_SEP_STR, buffer::buff, CHECK, common_get_height(), common_get_width(), env_node::env, ENV_NULL, env_universal_barrier(), get_umask(), hash_get(), history_get(), env_node::new_scope, env_node::next, proc_get_last_status(), proc_had_barrier, reader_get_buffer(), sb_append, sb_clear(), sb_printf(), and var_entry::val.

Referenced by autoload_names(), builtin_cd(), builtin_read(), builtin_set(), calc_prompt_width(), complete_cmd(), complete_variable(), env_init(), env_set_defaults(), exec_subshell(), expand_tilde_internal(), expand_var(), handle_locale(), highlight_get_color(), input_init(), kill_add(), kill_check_x_buffer(), parse_job(), parse_util_load(), path_get_cdpath(), path_get_config(), path_get_path(), print_variables(), reader_write_title(), and setup_path().

void env_get_names	(	array_list_t *	l,
		int	flags
	)

Insert all variable names into l.

These are not copies of the strings and should not be freed after use.

References add_key_to_hash(), add_key_to_list(), add_to_hash(), al_destroy(), al_foreach2(), al_init(), al_push(), CHECK, env_node::env, ENV_EXPORT, ENV_GLOBAL, ENV_LOCAL, ENV_UNEXPORT, ENV_UNIVERSAL, get_names_show_exported, get_names_show_unexported, hash_destroy(), hash_foreach2(), hash_get_keys(), hash_init(), hash_wcs_cmp(), hash_wcs_func(), env_node::new_scope, and env_node::next.

Referenced by complete_variable(), and print_variables().

static env_node_t* env_get_node ( const wchar_t * key ) [static]

Search all visible scopes in order for the specified key.

Return the first scope in which it was found.

References env_node::env, hash_get(), env_node::new_scope, and env_node::next.

Referenced by env_set().

void env_pop ( )

Pop the variable stack.

Used for implementing local variables for functions and for-loops.

References _, clear_hash_entry(), debug(), env_node::env, env_node::export, handle_locale(), has_changed, hash_destroy(), hash_foreach(), hash_get(), killme, local_scope_exports(), locale_variable, env_node::new_scope, env_node::next, and sanity_lose().

Referenced by builtin_else(), env_destroy(), and parser_push_block().

void env_push ( int new_scope )

Push the variable stack.

Used for implementing local variables for functions and for-loops.

References env_node::env, env_node::export, has_changed, hash_init(), hash_wcs_cmp(), hash_wcs_func(), local_scope_exports(), env_node::new_scope, and env_node::next.

Referenced by builtin_else(), and parser_push_block().

int env_remove	(	const wchar_t *	key,
		int	mode
	)

Remove environemnt variable.

Parameters:

	key	The name of the variable to remove
	mode	should be ENV_USER if this is a remove request from the user, 0 otherwise. If this is a user request, read-only variables can not be removed. The mode may also specify the scope of the variable that should be erased.

Returns:: zero if the variable existed, and non-zero if the variable did not exist

References al_destroy(), al_init(), al_push(), event_t::arguments, CHECK, ENV_GLOBAL, ENV_LOCAL, ENV_UNIVERSAL, ENV_USER, event_fire(), EVENT_VARIABLE, event_t::function_name, handle_locale(), hash_get(), is_locale(), event_t::param1, try_remove(), event_t::type, and event_t::variable.

Referenced by builtin_set().

int env_set	(	const wchar_t *	key,
		const wchar_t *	val,
		int	mode
	)

Set the value of the environment variable whose name matches key to val.

Memory policy: All keys and values are copied, the parameters can and should be freed by the caller afterwards

Parameters:

	key	The key
	val	The value
	mode	The type of the variable. Can be any combination of ENV_GLOBAL, ENV_LOCAL, ENV_EXPORT and ENV_USER. If mode is zero, the current variable space is searched and the current mode is used. If no current variable with the same name is found, ENV_LOCAL is assumed.

Returns:: 0 on suicess or an error code on failiure.

The current error codes are:

ENV_PERM, can only be returned when setting as a user, e.g. ENV_USER is set. This means that the user tried to change a read-only variable. ENV_INVALID, the variable name or mode was invalid

References al_destroy(), al_init(), al_push(), event_t::arguments, CHECK, contains, DIE_MEM, env_node::env, ENV_EXPORT, env_get_node(), ENV_GLOBAL, ENV_LOCAL, ENV_NULL, env_set(), ENV_UNEXPORT, ENV_UNIVERSAL, env_universal_barrier(), ENV_USER, event_fire(), EVENT_VARIABLE, env_node::export, var_entry::export, event_t::function_name, halloc(), halloc_free(), handle_locale(), has_changed, hash_get(), hash_put(), hash_remove(), is_locale(), env_node::new_scope, env_node::next, event_t::param1, proc_had_barrier, var_entry::size, event_t::type, var_entry::val, and event_t::variable.

Referenced by builtin_end(), builtin_fg(), builtin_for(), builtin_read(), env_init(), env_set(), env_set_defaults(), env_set_pwd(), main(), my_env_set(), parse_util_set_argv(), reader_interactive_init(), reader_run_command(), and setup_path().

static void start_fishd ( ) [static]

When fishd isn't started, this function is provided to env_universal as a callback, it tries to start up fishd.

It's implementation is a bit of a hack, since it evaluates a bit of shellscript, and it might be used at times when that might not be the best idea.

References _, buffer::buff, debug(), eval(), FISHD_CMD, sb_destroy(), sb_init(), sb_printf(), and TOP.

Referenced by env_init().

static int try_remove	(	env_node_t *	n,
		const wchar_t *	key,
		int	var_mode
	)			`[static]`

Attempt to remove/free the specified key/value pair from the specified hash table.

Returns:: zero if the variable was not found, non-zero otherwise

References env_node::env, ENV_LOCAL, var_entry::export, has_changed, hash_remove(), env_node::new_scope, and env_node::next.

Referenced by env_remove().

static void universal_callback	(	int	type,
		const wchar_t *	name,
		const wchar_t *	val
	)			`[static]`

Universal variable callback function.

This function makes sure the proper events are triggered when an event occurs.

References al_destroy(), al_init(), al_push(), event_t::arguments, event_fire(), EVENT_VARIABLE, event_t::function_name, handle_locale(), has_changed, is_locale(), event_t::param1, event_t::type, and event_t::variable.

Referenced by env_init().

Variable Documentation

char** __environ

This should be the same thing as environ, but it is possible only one of the two work.

..

Referenced by env_init().

const wchar_t* locale_variable[] [static]

Initial value:

{
        L"LANG",
        L"LC_ALL",
        L"LC_COLLATE",
        L"LC_CTYPE",
        L"LC_MESSAGES",
        L"LC_MONETARY",
        L"LC_NUMERIC",
        L"LC_TIME",
        (void *)0
}

List of all locale variable names.

Referenced by env_pop(), handle_locale(), and is_locale().


Data Structures
struct	env_node
	Struct representing one level in the function variable stack. More...
struct	var_entry
	A variable entry. More...
Defines
#define	FISHD_CMD L"fishd ^/tmp/fishd.log.%s"
	Command used to start fishd.
#define	ENV_NULL L"\x1d"
	Value denoting a null string.
Typedefs
typedef struct env_node	env_node_t
	Struct representing one level in the function variable stack.
typedef struct var_entry	var_entry_t
	A variable entry.
Functions
static void	clear_hash_entry (void key, void data)
	Free hash key and hash value.
static void	start_fishd ()
	When fishd isn't started, this function is provided to env_universal as a callback, it tries to start up fishd.
static mode_t	get_umask ()
	Return the current umask value.
static int	is_locale (const wchar_t *key)
	Checks if the specified variable is a locale variable.
static void	handle_locale ()
	Properly sets all locale information.
static void	universal_callback (int type, const wchar_t name, const wchar_t val)
	Universal variable callback function.
static void	setup_path ()
	Make sure the PATH variable contains the essaential directories.
int	env_set_pwd ()
	Update the PWD variable directory.
static void	env_set_defaults ()
	Set up default values for various variables if not defined.
void	env_init ()
	Initialize environment variable data.
void	env_destroy ()
	Destroy environment variable data.
static env_node_t *	env_get_node (const wchar_t *key)
	Search all visible scopes in order for the specified key.
int	env_set (const wchar_t key, const wchar_t val, int var_mode)
	Set the value of the environment variable whose name matches key to val.
static int	try_remove (env_node_t n, const wchar_t key, int var_mode)
	Attempt to remove/free the specified key/value pair from the specified hash table.
int	env_remove (const wchar_t *key, int var_mode)
	Remove environemnt variable.
wchar_t *	env_get (const wchar_t *key)
	Return the value of the variable with the specified name.
int	env_exist (const wchar_t *key, int mode)
	Returns 1 if the specified key exists.
static int	local_scope_exports (env_node_t *n)
	Returns true if the specified scope or any non-shadowed non-global subscopes contain an exported variable.
void	env_push (int new_scope)
	Push the variable stack.
void	env_pop ()
	Pop the variable stack.
static void	add_key_to_hash (void key, void data, void *aux)
	Function used with hash_foreach to insert keys of one table into another.
static void	add_to_hash (void k, void aux)
	Add key to hashtable.
static void	add_key_to_list (void key, void val, void *aux)
	Add key to list.
void	env_get_names (array_list_t *l, int flags)
	Insert all variable names into l.
static void	export_func1 (void k, void v, void *aux)
	Function used by env_export_arr to iterate over hashtable of variables.
static void	get_exported (env_node_t n, hash_table_t h)
	Get list of all exported variables.
static void	export_func2 (void k, void v, void *aux)
	Function used by env_export_arr to iterate over hashtable of variables.
char **	env_export_arr (int recalc)
	Returns an array containing all exported variables in a format suitable for execv.
Variables
char **	environ
	At init, we read all the environment variables from this array.
char **	__environ
	This should be the same thing as `environ`, but it is possible only one of the two work.
static env_node_t *	top = 0
	Top node on the function stack.
static env_node_t *	global_env = 0
	Bottom node on the function stack.
static hash_table_t *	global
	Table for global variables.
static hash_table_t	env_read_only
	Table of variables that may not be set using the set command.
static hash_table_t	env_electric
	Table of variables whose value is dynamically calculated, such as umask, status, etc.
static char **	export_arr = 0
	Exported variable array used by execv.
static buffer_t	export_buffer
	Buffer used for storing string contents for export_arr.
static int	has_changed = 1
	Flag for checking if we need to regenerate the exported variable array.
static string_buffer_t	dyn_var
	This stringbuffer is used to store the value of dynamically generated variables, such as history.
static int	get_names_show_exported
	Variable used by env_get_names to communicate auxiliary information to add_key_to_hash.
static int	get_names_show_unexported
	Variable used by env_get_names to communicate auxiliary information to add_key_to_hash.
static const wchar_t *	locale_variable []
	List of all locale variable names.