1 files changed, 336 insertions, 0 deletions
diff --git a/toolkit/components/xulstore/XULStore.js b/toolkit/components/xulstore/XULStore.js
new file mode 100644
index 000000000..c2721327c
--- /dev/null
+++ b/toolkit/components/xulstore/XULStore.js
@@ -0,0 +1,336 @@
+/* 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 Cc = Components.classes;
+const Ci = Components.interfaces;
+const Cr = Components.results;
+const Cu = Components.utils;
+
+// Enables logging and shorter save intervals.
+const debugMode = false;
+
+// Delay when a change is made to when the file is saved.
+// 30 seconds normally, or 3 seconds for testing
+const WRITE_DELAY_MS = (debugMode ? 3 : 30) * 1000;
+
+const XULSTORE_CONTRACTID = "@mozilla.org/xul/xulstore;1";
+const XULSTORE_CID = Components.ID("{6f46b6f4-c8b1-4bd4-a4fa-9ebbed0753ea}");
+const STOREDB_FILENAME = "xulstore.json";
+
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/Task.jsm");
+Cu.import('resource://gre/modules/XPCOMUtils.jsm');
+
+XPCOMUtils.defineLazyModuleGetter(this, "NetUtil", "resource://gre/modules/NetUtil.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "OS", "resource://gre/modules/osfile.jsm");
+
+function XULStore() {
+  if (!Services.appinfo.inSafeMode)
+    this.load();
+}
+
+XULStore.prototype = {
+  classID: XULSTORE_CID,
+  classInfo: XPCOMUtils.generateCI({classID: XULSTORE_CID,
+                                    contractID: XULSTORE_CONTRACTID,
+                                    classDescription: "XULStore",
+                                    interfaces: [Ci.nsIXULStore]}),
+  QueryInterface: XPCOMUtils.generateQI([Ci.nsIObserver, Ci.nsIXULStore,
+                                         Ci.nsISupportsWeakReference]),
+  _xpcom_factory: XPCOMUtils.generateSingletonFactory(XULStore),
+
+  /* ---------- private members ---------- */
+
+  /*
+   * The format of _data is _data[docuri][elementid][attribute]. For example:
+   *  {
+   *      "chrome://blah/foo.xul" : {
+   *                                    "main-window" : { aaa : 1, bbb : "c" },
+   *                                    "barColumn"   : { ddd : 9, eee : "f" },
+   *                                },
+   *
+   *      "chrome://foopy/b.xul" :  { ... },
+   *      ...
+   *  }
+   */
+  _data: {},
+  _storeFile: null,
+  _needsSaving: false,
+  _saveAllowed: true,
+  _writeTimer: Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer),
+
+  load: function () {
+    Services.obs.addObserver(this, "profile-before-change", true);
+
+    this._storeFile = Services.dirsvc.get("ProfD", Ci.nsIFile);
+    this._storeFile.append(STOREDB_FILENAME);
+
+    if (!this._storeFile.exists()) {
+      this.import();
+    } else {
+      this.readFile();
+    }
+  },
+
+  observe: function(subject, topic, data) {
+    this.writeFile();
+    if (topic == "profile-before-change") {
+      this._saveAllowed = false;
+    }
+  },
+
+  /*
+   * Internal function for logging debug messages to the Error Console window
+   */
+  log: function (message) {
+    if (!debugMode)
+      return;
+    dump("XULStore: " + message + "\n");
+    Services.console.logStringMessage("XULStore: " + message);
+  },
+
+  import: function() {
+    let localStoreFile = Services.dirsvc.get("ProfD", Ci.nsIFile);
+
+    localStoreFile.append("localstore.rdf");
+    if (!localStoreFile.exists()) {
+      return;
+    }
+
+    const RDF = Cc["@mozilla.org/rdf/rdf-service;1"].getService(Ci.nsIRDFService);
+    const persistKey = RDF.GetResource("http://home.netscape.com/NC-rdf#persist");
+
+    this.log("Import localstore from " + localStoreFile.path);
+
+    let localStoreURI = Services.io.newFileURI(localStoreFile).spec;
+    let localStore = RDF.GetDataSourceBlocking(localStoreURI);
+    let resources = localStore.GetAllResources();
+
+    while (resources.hasMoreElements()) {
+      let resource = resources.getNext().QueryInterface(Ci.nsIRDFResource);
+      let uri;
+
+      try {
+        uri = NetUtil.newURI(resource.ValueUTF8);
+      } catch (ex) {
+        continue; // skip invalid uris
+      }
+
+      // If this has a ref, then this is an attribute reference. Otherwise,
+      // this is a document reference.
+      if (!uri.hasRef)
+          continue;
+
+      // Verify that there the persist key is connected up.
+      let docURI = uri.specIgnoringRef;
+
+      if (!localStore.HasAssertion(RDF.GetResource(docURI), persistKey, resource, true))
+          continue;
+
+      let id = uri.ref;
+      let attrs = localStore.ArcLabelsOut(resource);
+
+      while (attrs.hasMoreElements()) {
+        let attr = attrs.getNext().QueryInterface(Ci.nsIRDFResource);
+        let value = localStore.GetTarget(resource, attr, true);
+
+        if (value instanceof Ci.nsIRDFLiteral) {
+          this.setValue(docURI, id, attr.ValueUTF8, value.Value);
+        }
+      }
+    }
+  },
+
+  readFile: function() {
+    const MODE_RDONLY = 0x01;
+    const FILE_PERMS  = 0o600;
+
+    let stream = Cc["@mozilla.org/network/file-input-stream;1"].
+                 createInstance(Ci.nsIFileInputStream);
+    let json = Cc["@mozilla.org/dom/json;1"].createInstance(Ci.nsIJSON);
+    try {
+      stream.init(this._storeFile, MODE_RDONLY, FILE_PERMS, 0);
+      this._data = json.decodeFromStream(stream, stream.available());
+    } catch (e) {
+      this.log("Error reading JSON: " + e);
+      // Ignore problem, we'll just continue on with an empty dataset.
+    } finally {
+      stream.close();
+    }
+  },
+
+  writeFile: Task.async(function* () {
+    if (!this._needsSaving)
+      return;
+
+    this._needsSaving = false;
+
+    this.log("Writing to xulstore.json");
+
+    try {
+      let data = JSON.stringify(this._data);
+      let encoder = new TextEncoder();
+
+      data = encoder.encode(data);
+      yield OS.File.writeAtomic(this._storeFile.path, data,
+                              { tmpPath: this._storeFile.path + ".tmp" });
+    } catch (e) {
+      this.log("Failed to write xulstore.json: " + e);
+      throw e;
+    }
+  }),
+
+  markAsChanged: function() {
+    if (this._needsSaving || !this._storeFile)
+      return;
+
+    // Don't write the file more than once every 30 seconds.
+    this._needsSaving = true;
+    this._writeTimer.init(this, WRITE_DELAY_MS, Ci.nsITimer.TYPE_ONE_SHOT);
+  },
+
+  /* ---------- interface implementation ---------- */
+
+  setValue: function (docURI, id, attr, value) {
+    this.log("Saving " + attr + "=" + value + " for id=" + id + ", doc=" + docURI);
+
+    if (!this._saveAllowed) {
+      Services.console.logStringMessage("XULStore: Changes after profile-before-change are ignored!");
+      return;
+    }
+
+    // bug 319846 -- don't save really long attributes or values.
+    if (id.length > 512 || attr.length > 512) {
+      throw Components.Exception("id or attribute name too long", Cr.NS_ERROR_ILLEGAL_VALUE);
+    }
+
+    if (value.length > 4096) {
+      Services.console.logStringMessage("XULStore: Warning, truncating long attribute value")
+      value = value.substr(0, 4096);
+    }
+
+    let obj = this._data;
+    if (!(docURI in obj)) {
+      obj[docURI] = {};
+    }
+    obj = obj[docURI];
+    if (!(id in obj)) {
+      obj[id] = {};
+    }
+    obj = obj[id];
+
+    // Don't set the value if it is already set to avoid saving the file.
+    if (attr in obj && obj[attr] == value)
+      return;
+
+    obj[attr] = value; // IE, this._data[docURI][id][attr] = value;
+
+    this.markAsChanged();
+  },
+
+  hasValue: function (docURI, id, attr) {
+    this.log("has store value for id=" + id + ", attr=" + attr + ", doc=" + docURI);
+
+    let ids = this._data[docURI];
+    if (ids) {
+      let attrs = ids[id];
+      if (attrs) {
+        return attr in attrs;
+      }
+    }
+
+    return false;
+  },
+
+  getValue: function (docURI, id, attr) {
+    this.log("get store value for id=" + id + ", attr=" + attr + ", doc=" + docURI);
+
+    let ids = this._data[docURI];
+    if (ids) {
+      let attrs = ids[id];
+      if (attrs) {
+        return attrs[attr] || "";
+      }
+    }
+
+    return "";
+  },
+
+  removeValue: function (docURI, id, attr) {
+    this.log("remove store value for id=" + id + ", attr=" + attr + ", doc=" + docURI);
+
+    if (!this._saveAllowed) {
+      Services.console.logStringMessage("XULStore: Changes after profile-before-change are ignored!");
+      return;
+    }
+
+    let ids = this._data[docURI];
+    if (ids) {
+      let attrs = ids[id];
+      if (attrs && attr in attrs) {
+        delete attrs[attr];
+
+        if (Object.getOwnPropertyNames(attrs).length == 0) {
+          delete ids[id];
+
+          if (Object.getOwnPropertyNames(ids).length == 0) {
+            delete this._data[docURI];
+          }
+        }
+
+        this.markAsChanged();
+      }
+    }
+  },
+
+  getIDsEnumerator: function (docURI) {
+    this.log("Getting ID enumerator for doc=" + docURI);
+
+    if (!(docURI in this._data))
+      return new nsStringEnumerator([]);
+
+    let result = [];
+    let ids = this._data[docURI];
+    if (ids) {
+      for (let id in this._data[docURI]) {
+        result.push(id);
+      }
+    }
+
+    return new nsStringEnumerator(result);
+  },
+
+  getAttributeEnumerator: function (docURI, id) {
+    this.log("Getting attribute enumerator for id=" + id + ", doc=" + docURI);
+
+    if (!(docURI in this._data) || !(id in this._data[docURI]))
+      return new nsStringEnumerator([]);
+
+    let attrs = [];
+    for (let attr in this._data[docURI][id]) {
+      attrs.push(attr);
+    }
+
+    return new nsStringEnumerator(attrs);
+  }
+};
+
+function nsStringEnumerator(items) {
+  this._items = items;
+}
+
+nsStringEnumerator.prototype = {
+  QueryInterface : XPCOMUtils.generateQI([Ci.nsIStringEnumerator]),
+  _nextIndex : 0,
+  hasMore: function() {
+    return this._nextIndex < this._items.length;
+  },
+  getNext : function() {
+    if (!this.hasMore())
+      throw Cr.NS_ERROR_NOT_AVAILABLE;
+    return this._items[this._nextIndex++];
+  },
+};
+
+this.NSGetFactory = XPCOMUtils.generateNSGetFactory([XULStore]);