gecko-dev/toolkit/components/thumbnails/PageThumbsStorageService.jsm

69 строки
2.0 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/. */
const THUMBNAIL_DIRECTORY = "thumbnails";
ChromeUtils.import("resource://gre/modules/XPCOMUtils.jsm", this);
ChromeUtils.import("resource://gre/modules/osfile.jsm", this);
XPCOMUtils.defineLazyGetter(this, "gCryptoHash", function() {
return Cc["@mozilla.org/security/hash;1"].createInstance(Ci.nsICryptoHash);
});
XPCOMUtils.defineLazyGetter(this, "gUnicodeConverter", function() {
let converter = Cc[
"@mozilla.org/intl/scriptableunicodeconverter"
].createInstance(Ci.nsIScriptableUnicodeConverter);
converter.charset = "utf8";
return converter;
});
function PageThumbsStorageService() {}
PageThumbsStorageService.prototype = {
classID: Components.ID("{97943eec-0e48-49ef-b7b7-cf4aa0109bb6}"),
QueryInterface: ChromeUtils.generateQI([Ci.nsIPageThumbsStorageService]),
// The path for the storage
_path: null,
get path() {
if (!this._path) {
this._path = OS.Path.join(
OS.Constants.Path.localProfileDir,
THUMBNAIL_DIRECTORY
);
}
return this._path;
},
getLeafNameForURL(aURL) {
if (typeof aURL != "string") {
throw new TypeError("Expecting a string");
}
let hash = this._calculateMD5Hash(aURL);
return hash + ".png";
},
getFilePathForURL(aURL) {
return OS.Path.join(this.path, this.getLeafNameForURL(aURL));
},
_calculateMD5Hash(aValue) {
let hash = gCryptoHash;
let value = gUnicodeConverter.convertToByteArray(aValue);
hash.init(hash.MD5);
hash.update(value, value.length);
return this._convertToHexString(hash.finish(false));
},
_convertToHexString(aData) {
let hex = "";
for (let i = 0; i < aData.length; i++) {
hex += ("0" + aData.charCodeAt(i).toString(16)).slice(-2);
}
return hex;
},
};
var EXPORTED_SYMBOLS = ["PageThumbsStorageService"];