toolkit/mozapps/downloads/DownloadPaths.jsm@6474c204b198 (annotated)
toolkit/mozapps/downloads/DownloadPaths.jsm
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ |
| michael@0 | 2 | /* vim: set ts=2 et sw=2 tw=80 filetype=javascript: */ |
| michael@0 | 3 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 4 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 5 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 6 | |
| michael@0 | 7 | this.EXPORTED_SYMBOLS = [ |
| michael@0 | 8 | "DownloadPaths", |
| michael@0 | 9 | ]; |
| michael@0 | 10 | |
| michael@0 | 11 | /** |
| michael@0 | 12 | * This module provides the DownloadPaths object which contains methods for |
| michael@0 | 13 | * giving names and paths to files being downloaded. |
| michael@0 | 14 | * |
| michael@0 | 15 | * List of methods: |
| michael@0 | 16 | * |
| michael@0 | 17 | * nsILocalFile |
| michael@0 | 18 | * createNiceUniqueFile(nsILocalFile aLocalFile) |
| michael@0 | 19 | * |
| michael@0 | 20 | * [string base, string ext] |
| michael@0 | 21 | * splitBaseNameAndExtension(string aLeafName) |
| michael@0 | 22 | */ |
| michael@0 | 23 | |
| michael@0 | 24 | const Cc = Components.classes; |
| michael@0 | 25 | const Ci = Components.interfaces; |
| michael@0 | 26 | const Cu = Components.utils; |
| michael@0 | 27 | const Cr = Components.results; |
| michael@0 | 28 | |
| michael@0 | 29 | this.DownloadPaths = { |
| michael@0 | 30 | /** |
| michael@0 | 31 | * Creates a uniquely-named file starting from the name of the provided file. |
| michael@0 | 32 | * If a file with the provided name already exists, the function attempts to |
| michael@0 | 33 | * create nice alternatives, like "base(1).ext" (instead of "base-1.ext"). |
| michael@0 | 34 | * |
| michael@0 | 35 | * If a unique name cannot be found, the function throws the XPCOM exception |
| michael@0 | 36 | * NS_ERROR_FILE_TOO_BIG. Other exceptions, like NS_ERROR_FILE_ACCESS_DENIED, |
| michael@0 | 37 | * can also be expected. |
| michael@0 | 38 | * |
| michael@0 | 39 | * @param aTemplateFile |
| michael@0 | 40 | * nsILocalFile whose leaf name is going to be used as a template. The |
| michael@0 | 41 | * provided object is not modified. |
| michael@0 | 42 | * @returns A new instance of an nsILocalFile object pointing to the newly |
| michael@0 | 43 | * created empty file. On platforms that support permission bits, the |
| michael@0 | 44 | * file is created with permissions 644. |
| michael@0 | 45 | */ |
| michael@0 | 46 | createNiceUniqueFile: function DP_createNiceUniqueFile(aTemplateFile) { |
| michael@0 | 47 | // Work on a clone of the provided template file object. |
| michael@0 | 48 | var curFile = aTemplateFile.clone().QueryInterface(Ci.nsILocalFile); |
| michael@0 | 49 | var [base, ext] = DownloadPaths.splitBaseNameAndExtension(curFile.leafName); |
| michael@0 | 50 | // Try other file names, for example "base(1).txt" or "base(1).tar.gz", |
| michael@0 | 51 | // only if the file name initially set already exists. |
| michael@0 | 52 | for (let i = 1; i < 10000 && curFile.exists(); i++) { |
| michael@0 | 53 | curFile.leafName = base + "(" + i + ")" + ext; |
| michael@0 | 54 | } |
| michael@0 | 55 | // At this point we hand off control to createUnique, which will create the |
| michael@0 | 56 | // file with the name we chose, if it is valid. If not, createUnique will |
| michael@0 | 57 | // attempt to modify it again, for example it will shorten very long names |
| michael@0 | 58 | // that can't be created on some platforms, and for which a normal call to |
| michael@0 | 59 | // nsIFile.create would result in NS_ERROR_FILE_NOT_FOUND. This can result |
| michael@0 | 60 | // very rarely in strange names like "base(9999).tar-1.gz" or "ba-1.gz". |
| michael@0 | 61 | curFile.createUnique(Ci.nsIFile.NORMAL_FILE_TYPE, 0644); |
| michael@0 | 62 | return curFile; |
| michael@0 | 63 | }, |
| michael@0 | 64 | |
| michael@0 | 65 | /** |
| michael@0 | 66 | * Separates the base name from the extension in a file name, recognizing some |
| michael@0 | 67 | * double extensions like ".tar.gz". |
| michael@0 | 68 | * |
| michael@0 | 69 | * @param aLeafName |
| michael@0 | 70 | * The full leaf name to be parsed. Be careful when processing names |
| michael@0 | 71 | * containing leading or trailing dots or spaces. |
| michael@0 | 72 | * @returns [base, ext] |
| michael@0 | 73 | * The base name of the file, which can be empty, and its extension, |
| michael@0 | 74 | * which always includes the leading dot unless it's an empty string. |
| michael@0 | 75 | * Concatenating the two items always results in the original name. |
| michael@0 | 76 | */ |
| michael@0 | 77 | splitBaseNameAndExtension: function DP_splitBaseNameAndExtension(aLeafName) { |
| michael@0 | 78 | // The following regular expression is built from these key parts: |
| michael@0 | 79 | // .*? Matches the base name non-greedily. |
| michael@0 | 80 | // \.[A-Z0-9]{1,3} Up to three letters or numbers preceding a |
| michael@0 | 81 | // double extension. |
| michael@0 | 82 | // \.(?:gz|bz2|Z) The second part of common double extensions. |
| michael@0 | 83 | // \.[^.]* Matches any extension or a single trailing dot. |
| michael@0 | 84 | var [, base, ext] = /(.*?)(\.[A-Z0-9]{1,3}\.(?:gz|bz2|Z)|\.[^.]*)?$/i |
| michael@0 | 85 | .exec(aLeafName); |
| michael@0 | 86 | // Return an empty string instead of undefined if no extension is found. |
| michael@0 | 87 | return [base, ext || ""]; |
| michael@0 | 88 | } |
| michael@0 | 89 | }; |
