tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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ManifestFinder.sys.mjs (1806B)

      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 https://mozilla.org/MPL/2.0/. */
      4 
      5 export var ManifestFinder = {
      6  /**
      7   * Check from content process if DOM Window has a conforming
      8   * manifest link relationship.
      9   *
     10   * @param aContent DOM Window to check.
     11   * @return {Promise<boolean>}
     12   */
     13  contentHasManifestLink(aContent) {
     14    if (!aContent || isXULBrowser(aContent)) {
     15      throw new TypeError("Invalid input.");
     16    }
     17    return checkForManifest(aContent);
     18  },
     19 
     20  /**
     21   * Check from a XUL browser (parent process) if it's content document has a
     22   * manifest link relationship.
     23   *
     24   * @param aBrowser The XUL browser to check.
     25   * @return {Promise}
     26   */
     27  async browserHasManifestLink(aBrowser) {
     28    if (!isXULBrowser(aBrowser)) {
     29      throw new TypeError("Invalid input.");
     30    }
     31 
     32    const actor =
     33      aBrowser.browsingContext.currentWindowGlobal.getActor("ManifestMessages");
     34    const reply = await actor.sendQuery("DOM:WebManifest:hasManifestLink");
     35    return reply.result;
     36  },
     37 };
     38 
     39 function isXULBrowser(aBrowser) {
     40  if (!aBrowser || !aBrowser.namespaceURI || !aBrowser.localName) {
     41    return false;
     42  }
     43  const XUL_NS =
     44    "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
     45  return aBrowser.namespaceURI === XUL_NS && aBrowser.localName === "browser";
     46 }
     47 
     48 function checkForManifest(aWindow) {
     49  // Only top-level browsing contexts are valid.
     50  if (!aWindow || aWindow.top !== aWindow) {
     51    return false;
     52  }
     53  const elem = aWindow.document.querySelector("link[rel~='manifest']");
     54  // Only if we have an element and a non-empty href attribute.
     55  if (!elem || !elem.getAttribute("href")) {
     56    return false;
     57  }
     58  return true;
     59 }