1 /* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 * Provides methods for giving names and paths to files being downloaded.
9 export var DownloadPaths = {
11 * Sanitizes an arbitrary string via mimeSvc.validateFileNameForSaving.
13 * If the filename being validated is one that was returned from a
14 * file picker, pass false for compressWhitespaces and true for
15 * allowInvalidFilenames. Otherwise, the default values of the arguments
16 * should generally be used.
18 * @param {string} leafName The full leaf name to sanitize
19 * @param {boolean} [compressWhitespaces] Whether consecutive whitespaces
20 * should be compressed. The default value is true.
21 * @param {boolean} [allowInvalidFilenames] Allow invalid and dangerous
22 * filenames and extensions as is.
26 { compressWhitespaces = true, allowInvalidFilenames = false } = {}
28 const mimeSvc = Cc["@mozilla.org/mime;1"].getService(Ci.nsIMIMEService);
30 let flags = mimeSvc.VALIDATE_SANITIZE_ONLY | mimeSvc.VALIDATE_DONT_TRUNCATE;
31 if (!compressWhitespaces) {
32 flags |= mimeSvc.VALIDATE_DONT_COLLAPSE_WHITESPACE;
34 if (allowInvalidFilenames) {
35 flags |= mimeSvc.VALIDATE_ALLOW_INVALID_FILENAMES;
37 return mimeSvc.validateFileNameForSaving(leafName, "", flags);
41 * Creates a uniquely-named file starting from the name of the provided file.
42 * If a file with the provided name already exists, the function attempts to
43 * create nice alternatives, like "base(1).ext" (instead of "base-1.ext").
45 * If a unique name cannot be found, the function throws the XPCOM exception
46 * NS_ERROR_FILE_TOO_BIG. Other exceptions, like NS_ERROR_FILE_ACCESS_DENIED,
47 * can also be expected.
50 * nsIFile whose leaf name is going to be used as a template. The
51 * provided object is not modified.
53 * @return A new instance of an nsIFile object pointing to the newly created
54 * empty file. On platforms that support permission bits, the file is
55 * created with permissions 644.
57 createNiceUniqueFile(templateFile) {
58 // Work on a clone of the provided template file object.
59 let curFile = templateFile.clone().QueryInterface(Ci.nsIFile);
60 let [base, ext] = DownloadPaths.splitBaseNameAndExtension(curFile.leafName);
61 // Try other file names, for example "base(1).txt" or "base(1).tar.gz",
62 // only if the file name initially set already exists.
63 for (let i = 1; i < 10000 && curFile.exists(); i++) {
64 curFile.leafName = base + "(" + i + ")" + ext;
66 // At this point we hand off control to createUnique, which will create the
67 // file with the name we chose, if it is valid. If not, createUnique will
68 // attempt to modify it again, for example it will shorten very long names
69 // that can't be created on some platforms, and for which a normal call to
70 // nsIFile.create would result in NS_ERROR_FILE_NOT_FOUND. This can result
71 // very rarely in strange names like "base(9999).tar-1.gz" or "ba-1.gz".
72 curFile.createUnique(Ci.nsIFile.NORMAL_FILE_TYPE, 0o644);
77 * Separates the base name from the extension in a file name, recognizing some
78 * double extensions like ".tar.gz".
81 * The full leaf name to be parsed. Be careful when processing names
82 * containing leading or trailing dots or spaces.
85 * The base name of the file, which can be empty, and its extension,
86 * which always includes the leading dot unless it's an empty string.
87 * Concatenating the two items always results in the original name.
89 splitBaseNameAndExtension(leafName) {
90 // The following regular expression is built from these key parts:
91 // .*? Matches the base name non-greedily.
92 // \.[A-Z0-9]{1,3} Up to three letters or numbers preceding a
94 // \.(?:gz|bz2|Z) The second part of common double extensions.
95 // \.[^.]* Matches any extension or a single trailing dot.
96 let [, base, ext] = /(.*?)(\.[A-Z0-9]{1,3}\.(?:gz|bz2|Z)|\.[^.]*)?$/i.exec(
99 // Return an empty string instead of undefined if no extension is found.
100 return [base, ext || ""];