Struct xdg::BaseDirectories

pub struct BaseDirectories { /* fields omitted */ }

BaseDirectories allows to look up paths to configuration, data, cache and runtime files in well-known locations according to the [X Desktop Group Base Directory specification][xdg-basedir]. [xdg-basedir]: http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html

The Base Directory specification defines four kinds of files:

• Configuration files store the application's settings and are often modified during runtime;
• Data files store supplementary data, such as graphic assets, precomputed tables, documentation, or architecture-independent source code;
• Cache files store non-essential, transient data that provides a runtime speedup;
• Runtime files include filesystem objects such are sockets or named pipes that are used for communication internal to the application. Runtime files must not be accessible to anyone except current user.

Examples

To configure paths for application myapp:

extern crate xdg;
let xdg_dirs = xdg::BaseDirectories::with_prefix("myapp").unwrap();

To store configuration:

let config_path = xdg_dirs.place_config_file("config.ini")
                          .expect("cannot create configuration directory");
let mut config_file = try!(File::create(config_path));
try!(write!(&mut config_file, "configured = 1"));

The config.ini file will appear in the proper location for desktop configuration files, most likely ~/.config/myapp/config.ini. The leading directories will be automatically created.

To retrieve supplementary data:

let logo_path = xdg_dirs.find_data_file("logo.png")
                        .expect("application data not present");
let mut logo_file = try!(File::open(logo_path));
let mut logo = Vec::new();
try!(logo_file.read_to_end(&mut logo));

The logo.png will be searched in the proper locations for supplementary data files, most likely ~/.local/share/myapp/logo.png, then /usr/local/share/myapp/logo.png and /usr/share/myapp/logo.png.

Methods

impl BaseDirectories

pub fn new() -> Result<BaseDirectories, BaseDirectoriesError>

Reads the process environment, determines the XDG base directories, and returns a value that can be used for lookup. The following environment variables are examined:

• HOME; if not set: use the same fallback as std::env::home_dir(); if still not available: return an error.
• XDG_DATA_HOME; if not set: assumed to be $HOME/.local/share.
• XDG_CONFIG_HOME; if not set: assumed to be $HOME/.config.
• XDG_CACHE_HOME; if not set: assumed to be $HOME/.cache.
• XDG_DATA_DIRS; if not set: assumed to be /usr/local/share:/usr/share.
• XDG_CONFIG_DIRS; if not set: assumed to be /etc/xdg.
• XDG_RUNTIME_DIR; if not accessible or permissions are not 0700: record as inaccessible (can be queried with has_runtime_directory).

As per specification, if an environment variable contains a relative path, the behavior is the same as if it was not set.

pub fn with_prefix<P>(
    prefix: P
) -> Result<BaseDirectories, BaseDirectoriesError> where
    P: AsRef<Path>, 

Same as new(), but prefix is implicitly prepended to every path that is looked up.

pub fn with_profile<P1, P2>(
    prefix: P1,
    profile: P2
) -> Result<BaseDirectories, BaseDirectoriesError> where
    P1: AsRef<Path>,
    P2: AsRef<Path>, 

Same as with_prefix(), with profile also implicitly prepended to every path that is looked up, but only for user-specific directories.

This allows each user to have mutliple "profiles" with different user-specific data.

For example:

let dirs = BaseDirectories::with_profile("program-name", "profile-name")
                           .unwrap();
dirs.find_data_file("bar.jpg");
dirs.find_config_file("foo.conf");

will find /usr/share/program-name/bar.jpg (without profile-name) and ~/.config/program-name/profile-name/foo.conf.

pub fn has_runtime_directory(&self) -> bool

Returns true if XDG_RUNTIME_DIR is available, false otherwise.

pub fn place_config_file<P>(&self, path: P) -> Result<PathBuf> where
    P: AsRef<Path>, 

Given a relative path path, returns an absolute path in XDG_CONFIG_HOME where a configuration file may be stored. Leading directories in the returned path are pre-created; if that is not possible, an error is returned.

pub fn place_data_file<P>(&self, path: P) -> Result<PathBuf> where
    P: AsRef<Path>, 

Like place_config_file(), but for a data file in XDG_DATA_HOME.

pub fn place_cache_file<P>(&self, path: P) -> Result<PathBuf> where
    P: AsRef<Path>, 

Like place_config_file(), but for a cache file in XDG_CACHE_HOME.

pub fn place_runtime_file<P>(&self, path: P) -> Result<PathBuf> where
    P: AsRef<Path>, 

Like place_config_file(), but for a runtime file in XDG_RUNTIME_DIR. If XDG_RUNTIME_DIR is not available, returns an error.

pub fn find_config_file<P>(&self, path: P) -> Option<PathBuf> where
    P: AsRef<Path>, 

Given a relative path path, returns an absolute path to an existing configuration file, or None. Searches XDG_CONFIG_HOME and then XDG_CONFIG_DIRS.

Important traits for FileFindIterator

impl Iterator for FileFindIterator type Item = PathBuf;

pub fn find_config_files<P>(&self, path: P) -> FileFindIterator where
    P: AsRef<Path>, 

Given a relative path path, returns an iterator yielding absolute paths to existing configuration files, in XDG_CONFIG_DIRS and XDG_CONFIG_HOME. Paths are produced in order from lowest priority to highest.

pub fn find_data_file<P>(&self, path: P) -> Option<PathBuf> where
    P: AsRef<Path>, 

Given a relative path path, returns an absolute path to an existing data file, or None. Searches XDG_DATA_HOME and then XDG_DATA_DIRS.

Important traits for FileFindIterator

impl Iterator for FileFindIterator type Item = PathBuf;

pub fn find_data_files<P>(&self, path: P) -> FileFindIterator where
    P: AsRef<Path>, 

Given a relative path path, returns an iterator yielding absolute paths to existing data files, in XDG_DATA_DIRS and XDG_DATA_HOME. Paths are produced in order from lowest priority to highest.

pub fn find_cache_file<P>(&self, path: P) -> Option<PathBuf> where
    P: AsRef<Path>, 

Given a relative path path, returns an absolute path to an existing cache file, or None. Searches XDG_CACHE_HOME.

pub fn find_runtime_file<P>(&self, path: P) -> Option<PathBuf> where
    P: AsRef<Path>, 

Given a relative path path, returns an absolute path to an existing runtime file, or None. Searches XDG_RUNTIME_DIR. If XDG_RUNTIME_DIR is not available, returns None.

pub fn create_config_directory<P>(&self, path: P) -> Result<PathBuf> where
    P: AsRef<Path>, 

Given a relative path path, returns an absolute path to a configuration directory in XDG_CONFIG_HOME. The directory and all directories leading to it are created if they did not exist; if that is not possible, an error is returned.

pub fn create_data_directory<P>(&self, path: P) -> Result<PathBuf> where
    P: AsRef<Path>, 

Like create_config_directory(), but for a data directory in XDG_DATA_HOME.

pub fn create_cache_directory<P>(&self, path: P) -> Result<PathBuf> where
    P: AsRef<Path>, 

Like create_config_directory(), but for a cache directory in XDG_CACHE_HOME.

pub fn create_runtime_directory<P>(&self, path: P) -> Result<PathBuf> where
    P: AsRef<Path>, 

Like create_config_directory(), but for a runtime directory in XDG_RUNTIME_DIR. If XDG_RUNTIME_DIR is not available, returns an error.

pub fn list_config_files<P>(&self, path: P) -> Vec<PathBuf> where
    P: AsRef<Path>, 

Given a relative path path, list absolute paths to all files in directories with path path in XDG_CONFIG_HOME and XDG_CONFIG_DIRS.

pub fn list_config_files_once<P>(&self, path: P) -> Vec<PathBuf> where
    P: AsRef<Path>, 

Like list_config_files, but only the first occurence of every distinct filename is returned.

pub fn list_data_files<P>(&self, path: P) -> Vec<PathBuf> where
    P: AsRef<Path>, 

Given a relative path path, lists absolute paths to all files in directories with path path in XDG_DATA_HOME and XDG_DATA_DIRS.

pub fn list_data_files_once<P>(&self, path: P) -> Vec<PathBuf> where
    P: AsRef<Path>, 

Like list_data_files, but only the first occurence of every distinct filename is returned.

pub fn list_cache_files<P>(&self, path: P) -> Vec<PathBuf> where
    P: AsRef<Path>, 

Given a relative path path, lists absolute paths to all files in directories with path path in XDG_CACHE_HOME.

pub fn list_runtime_files<P>(&self, path: P) -> Vec<PathBuf> where
    P: AsRef<Path>, 

Given a relative path path, lists absolute paths to all files in directories with path path in XDG_RUNTIME_DIR. If XDG_RUNTIME_DIR is not available, returns an empty Vec.

pub fn get_data_home(&self) -> PathBuf

Returns the user-specific data directory (set by XDG_DATA_HOME).

pub fn get_config_home(&self) -> PathBuf

Returns the user-specific configuration directory (set by XDG_CONFIG_HOME).

pub fn get_cache_home(&self) -> PathBuf

Returns the user-specific directory for non-essential (cached) data (set by XDG_CACHE_HOME).

pub fn get_data_dirs(&self) -> Vec<PathBuf>

Returns a preference ordered (preferred to less preferred) list of supplementary data directories, ordered by preference (set by XDG_DATA_DIRS).

pub fn get_config_dirs(&self) -> Vec<PathBuf>

Returns a preference ordered (preferred to less preferred) list of supplementary configuration directories (set by XDG_CONFIG_DIRS).

Trait Implementations

impl Clone for BaseDirectories

fn clone(&self) -> BaseDirectories

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for BaseDirectories

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.