nsupdateservice.js

从国外的站点上淘的个人财务管理系统．开源．

      if (programFilesDir.contains(appDir, true)) {
        var relativePath = appDir.getRelativeDescriptor(programFilesDir);
        var userLocalDir = fileLocator.get(KEY_LOCALDATA,
            Components.interfaces.nsILocalFile).parent;
        appDir.setRelativeDescriptor(userLocalDir, relativePath);
      }
    }
    catch (e) {}
//@line 379 "/c/builds/1813/mozilla/toolkit/mozapps/update/src/nsUpdateService.js.in"
  }
  appDir.append(DIR_UPDATES);
  appDir.append("0");
  if (!appDir.exists() && !key)
    appDir.create(nsILocalFile.DIRECTORY_TYPE, PERMS_DIRECTORY);
  return appDir;
}

/**
 * Reads the update state from the update.status file in the specified
 * directory.
 * @param   dir
 *          The dir to look for an update.status file in
 * @returns The status value of the update.
 */
function readStatusFile(dir) {
  var statusFile = dir.clone();
  statusFile.append(FILE_UPDATE_STATUS);
  LOG("General", "Reading Status File: " + statusFile.path);
  return readStringFromFile(statusFile) || STATE_NONE;
}

/**
 * Writes the current update operation/state to a file in the patch 
 * directory, indicating to the patching system that operations need
 * to be performed.
 * @param   dir
 *          The patch directory where the update.status file should be 
 *          written.
 * @param   state
 *          The state value to write.
 */
function writeStatusFile(dir, state) {
  var statusFile = dir.clone();
  statusFile.append(FILE_UPDATE_STATUS);
  writeStringToFile(statusFile, state);
}

/**
 * Removes the Updates Directory
 * @param   key
 *          The Directory Service Key under which update directory resides
 *          (optional).
 */
function cleanUpUpdatesDir(key) {
  // Bail out if we don't have appropriate permissions
  var updateDir;
  try {
    updateDir = getUpdatesDir(key);
  }
  catch (e) {
    return;
  }

  var e = updateDir.directoryEntries;
  while (e.hasMoreElements()) {
    var f = e.getNext().QueryInterface(Components.interfaces.nsIFile);
    // Preserve the last update log file for debugging purposes
    if (f.leafName == FILE_UPDATE_LOG) {
      try {
        var dir = f.parent.parent;
        var logFile = dir.clone();
        logFile.append(FILE_LAST_LOG);
        if (logFile.exists())
          logFile.remove(false);
        f.copyTo(dir, FILE_LAST_LOG);
      }
      catch (e) {
        LOG("General", "Failed to copy file: " + f.path);
      }
    }
    // Now, recursively remove this file.  The recusive removal is really
    // only needed on Mac OSX because this directory will contain a copy of
    // updater.app, which is itself a directory.
    try {
      f.remove(true);
    }
    catch (e) {
      LOG("General", "Failed to remove file: " + f.path);
    }
  }
  try {
    updateDir.remove(false);
  } catch (e) {
    LOG("General", "Failed to remove update directory: " + updateDir.path + 
        " - This is almost always bad. Exception = " + e);
    throw e;
  }
}

/**
 * Clean up updates list and the updates directory.
 * @param   key
 *          The Directory Service Key under which update directory resides
 *          (optional).
 */
function cleanupActiveUpdate(key) {
  // Move the update from the Active Update list into the Past Updates list.
  var um = 
      Components.classes["@mozilla.org/updates/update-manager;1"].
      getService(Components.interfaces.nsIUpdateManager);
  um.activeUpdate = null;
  um.saveUpdates();

  // Now trash the updates directory, since we're done with it
  cleanUpUpdatesDir(key);
}

/**
 * Gets a preference value, handling the case where there is no default.
 * @param   func
 *          The name of the preference function to call, on nsIPrefBranch
 * @param   preference
 *          The name of the preference
 * @param   defaultValue
 *          The default value to return in the event the preference has 
 *          no setting
 * @returns The value of the preference, or undefined if there was no
 *          user or default value.
 */
function getPref(func, preference, defaultValue) {
  try {
    return gPref[func](preference);
  }
  catch (e) {
  }
  return defaultValue;
}

/**
 * Gets the current value of the locale.  It's possible for this preference to
 * be localized, so we have to do a little extra work here.  Similar code
 * exists in nsHttpHandler.cpp when building the UA string.
 */
function getLocale() {
  try {
    return gPref.getComplexValue(PREF_GENERAL_USERAGENT_LOCALE,
                                 nsIPrefLocalizedString).data;
  } catch (e) {}

  return gPref.getCharPref(PREF_GENERAL_USERAGENT_LOCALE);
}

/**
 * Read the update channel from defaults only.  We do this to ensure that
 * the channel is tightly coupled with the application and does not apply
 * to other instances of the application that may use the same profile.
 */
function getUpdateChannel() {
  var channel = "default";
  var prefName;
  var prefValue;

  var defaults =
      gPref.QueryInterface(Components.interfaces.nsIPrefService).
      getDefaultBranch(null);
  try {
    channel = defaults.getCharPref(PREF_APP_UPDATE_CHANNEL);
  } catch (e) {
    // use default when pref not found
  }

  try {
    var partners = gPref.getChildList(PREF_PARTNER_BRANCH, { });
    if (partners.length) {
      channel += "-cck";
      partners.sort();

      for each (prefName in partners) {
        prefValue = gPref.getCharPref(prefName);
        channel += "-" + prefValue;
      }
    }
  }
  catch (e) {
    Components.utils.reportError(e);
  }

  return channel;
}

/**
 * An enumeration of items in a JS array.
 * @constructor
 */
function ArrayEnumerator(aItems) {
  this._index = 0;
  if (aItems) {
    for (var i = 0; i < aItems.length; ++i) {
      if (!aItems[i])
        aItems.splice(i, 1);      
    }
  }
  this._contents = aItems;
}

ArrayEnumerator.prototype = {
  _index: 0,
  _contents: [],
  
  hasMoreElements: function() {
    return this._index < this._contents.length;
  },
  
  getNext: function() {
    return this._contents[this._index++];      
  }
};

/**
 * Trims a prefix from a string.
 * @param   string
 *          The source string
 * @param   prefix
 *          The prefix to remove.
 * @returns The suffix (string - prefix)
 */
function stripPrefix(string, prefix) {
  return string.substr(prefix.length);
}

/**
 * Writes a string of text to a file.  A newline will be appended to the data
 * written to the file.  This function only works with ASCII text.
 */
function writeStringToFile(file, text) {
  var fos =
      Components.classes["@mozilla.org/network/safe-file-output-stream;1"].
      createInstance(nsIFileOutputStream);
  var modeFlags = MODE_WRONLY | MODE_CREATE | MODE_TRUNCATE;
  if (!file.exists()) 
    file.create(nsILocalFile.NORMAL_FILE_TYPE, PERMS_FILE);
  fos.init(file, modeFlags, PERMS_FILE, 0);
  text += "\n";
  fos.write(text, text.length);    
  closeSafeOutputStream(fos);
}

/**
 * Reads a string of text from a file.  A trailing newline will be removed
 * before the result is returned.  This function only works with ASCII text.
 */
function readStringFromFile(file) {
  var fis =
      Components.classes["@mozilla.org/network/file-input-stream;1"].
      createInstance(nsIFileInputStream);
  var modeFlags = MODE_RDONLY;
  if (!file.exists())
    return null;
  fis.init(file, modeFlags, PERMS_FILE, 0);
  var sis =
      Components.classes["@mozilla.org/scriptableinputstream;1"].
      createInstance(Components.interfaces.nsIScriptableInputStream);
  sis.init(fis);
  var text = sis.read(sis.available());
  sis.close();
  if (text[text.length - 1] == "\n")
    text = text.slice(0, -1);
  return text;
}

function getObserverService()
{
  return Components.classes["@mozilla.org/observer-service;1"]
                   .getService(Components.interfaces.nsIObserverService);
}

/**
 * Update Patch
 * @param   patch
 *          A <patch> element to initialize this object with
 * @throws if patch has a size of 0
 * @constructor
 */
function UpdatePatch(patch) {
  this._properties = {};
  for (var i = 0; i < patch.attributes.length; ++i) {
    var attr = patch.attributes.item(i);
    attr.QueryInterface(Components.interfaces.nsIDOMAttr);
    switch (attr.name) {
    case "selected":
      this.selected = attr.value == "true";
      break;
    case "size":
      if (0 == parseInt(attr.value)) {
        LOG("UpdatePatch", "0-sized patch!");
        throw Components.results.NS_ERROR_ILLEGAL_VALUE;
      }
    default:
      this[attr.name] = attr.value;
      break;
    };
  }
}
UpdatePatch.prototype = {
  /**
   * See nsIUpdateService.idl
   */
  serialize: function(updates) {
    var patch = updates.createElementNS(URI_UPDATE_NS, "patch");
    patch.setAttribute("type", this.type);
    patch.setAttribute("URL", this.URL);
    patch.setAttribute("hashFunction", this.hashFunction);
    patch.setAttribute("hashValue", this.hashValue);
    patch.setAttribute("size", this.size);
    patch.setAttribute("selected", this.selected);
    patch.setAttribute("state", this.state);
    
    for (var p in this._properties) {
      if (this._properties[p].present)
        patch.setAttribute(p, this._properties[p].data);
    }
    
    return patch; 
  },
  
  /**
   * A hash of custom properties
   */
  _properties: null,
  
  /**
   * See nsIWritablePropertyBag.idl
   */
  setProperty: function(name, value) {
    this._properties[name] = { data: value, present: true };
  },
  
  /**
   * See nsIWritablePropertyBag.idl
   */
  deleteProperty: function(name) {
    if (name in this._properties)
      this._properties[name].present = false;
    else
      throw Components.results.NS_ERROR_FAILURE;
  },
  
  /**
   * See nsIPropertyBag.idl
   */
  get enumerator() {
    var properties = [];
    for (var p in this._properties)
      properties.push(this._properties[p].data);
    return new ArrayEnumerator(properties);
  },
  
  /**
   * See nsIPropertyBag.idl
   */
  getProperty: function(name) {
    if (name in this._properties &&
        this._properties[name].present)
      return this._properties[name].data;
    throw Components.results.NS_ERROR_FAILURE;
  },
  
  /**
   * Returns whether or not the update.status file for this patch exists at the 
   * appropriate location. 
   */
  get statusFileExists() {
    var statusFile = getUpdatesDir();
    statusFile.append(FILE_UPDATE_STATUS);
    return statusFile.exists();
  },
  
  /**
   * See nsIUpdateService.idl
   */
  get state() {
    if (!this.statusFileExists)
      return STATE_NONE;
    return this._properties.state;
  },
  set state(val) {
    this._properties.state = val;
  },
  
  /**
   * See nsISupports.idl
   */
  QueryInterface: function(iid) {
    if (!iid.equals(Components.interfaces.nsIUpdatePatch) &&
        !iid.equals(Components.interfaces.nsIPropertyBag) && 
        !iid.equals(Components.interfaces.nsIWritablePropertyBag) && 
        !iid.equals(Components.interfaces.nsISupports))
      throw Components.results.NS_ERROR_NO_INTERFACE;
    return this;
  }
};

/**
 * Update
 * Implements nsIUpdate
 * @param   update
 *          An <update> element to initialize this object with
 * @throws if the update contains no patches