gecko/toolkit/components/osfile/ospath_unix_back.jsm
2012-07-26 21:17:22 -04:00

133 lines
3.9 KiB
JavaScript

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
/**
* Handling native paths.
*
* This module contains a number of functions destined to simplify
* working with native paths through a cross-platform API. Functions
* of this module will only work with the following assumptions:
*
* - paths are valid;
* - paths are defined with one of the grammars that this module can
* parse (see later);
* - all path concatenations go through function |join|.
*/
if (typeof Components != "undefined") {
var EXPORTED_SYMBOLS = ["OS"];
Components.utils.import("resource://gre/modules/osfile/osfile_unix_allthreads.jsm");
}
(function(exports) {
"use strict";
if (!exports.OS) {
exports.OS = {};
}
if (!exports.OS.Unix) {
exports.OS.Unix = {};
}
if (exports.OS.Unix.Path) {
return; // Avoid double-initialization
}
exports.OS.Unix.Path = {
/**
* Return the final part of the path.
* The final part of the path is everything after the last "/".
*/
basename: function basename(path) {
return path.slice(path.lastIndexOf("/") + 1);
},
/**
* Return the directory part of the path.
* The directory part of the path is everything before the last
* "/". If the last few characters of this part are also "/",
* they are ignored.
*
* If the path contains no directory, return ".".
*/
dirname: function dirname(path) {
let index = path.lastIndexOf("/");
if (index == -1) {
return ".";
}
while (index >= 0 && path[index] == "/") {
--index;
}
return path.slice(0, index + 1);
},
/**
* Join path components.
* This is the recommended manner of getting the path of a file/subdirectory
* in a directory.
*
* Example: Obtaining $TMP/foo/bar in an OS-independent manner
* var tmpDir = OS.Path.to("TmpD");
* var path = OS.Path.join(tmpDir, "foo", "bar");
*
* Under Unix, this will return "/tmp/foo/bar".
*/
join: function join(path /*...*/) {
// If there is a path that starts with a "/", eliminate everything before
let paths = [];
for each(let i in arguments) {
if (i.length != 0 && i[0] == "/") {
paths = [i];
} else {
paths.push(i);
}
}
return paths.join("/");
},
/**
* Normalize a path by removing any unneeded ".", "..", "//".
*/
normalize: function normalize(path) {
let stack = [];
let absolute;
if (path.length >= 0 && path[0] == "/") {
absolute = true;
} else {
absolute = false;
}
path.split("/").forEach(function loop(v) {
switch (v) {
case "": case ".":// fallthrough
break;
case "..":
if (stack.length == 0) {
if (absolute) {
throw new Error("Path is ill-formed: attempting to go past root");
} else {
stack.push("..");
}
} else {
stack.pop();
}
break;
default:
stack.push(v);
}
});
let string = stack.join("/");
return absolute ? "/" + string : string;
},
/**
* Return the components of a path.
* You should generally apply this function to a normalized path.
*
* @return {{
* {bool} absolute |true| if the path is absolute, |false| otherwise
* {array} components the string components of the path
* }}
*
* Other implementations may add additional OS-specific informations.
*/
split: function split(path) {
return {
absolute: path.length && path[0] == "/",
components: path.split("/")
};
}
};
}(this));