Issue #1258 - Part 1: Import mailnews, ldap, and mork from comm-esr52.9.1

mailnews/db/gloda/modules/log4moz.js

@@ -0,0 +1,932 @@
+/* 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/. */
+
+this.EXPORTED_SYMBOLS = ['Log4Moz'];
+
+Components.utils.import("resource://gre/modules/Services.jsm");
+
+var Cc = Components.classes;
+var Ci = Components.interfaces;
+var Cr = Components.results;
+var Cu = Components.utils;
+
+var MODE_RDONLY   = 0x01;
+var MODE_WRONLY   = 0x02;
+var MODE_CREATE   = 0x08;
+var MODE_APPEND   = 0x10;
+var MODE_TRUNCATE = 0x20;
+
+var PERMS_FILE      = parseInt("0644", 8);
+var PERMS_DIRECTORY = parseInt("0755", 8);
+
+var ONE_BYTE = 1;
+var ONE_KILOBYTE = 1024 * ONE_BYTE;
+var ONE_MEGABYTE = 1024 * ONE_KILOBYTE;
+
+var DEFAULT_NETWORK_TIMEOUT_DELAY = 5;
+
+var CDATA_START = "<![CDATA[";
+var CDATA_END = "]]>";
+var CDATA_ESCAPED_END = CDATA_END + "]]&gt;" + CDATA_START;
+
+var Log4Moz = {
+  Level: {
+    Fatal:  70,
+    Error:  60,
+    Warn:   50,
+    Info:   40,
+    Config: 30,
+    Debug:  20,
+    Trace:  10,
+    All:    0,
+    Desc: {
+      70: "FATAL",
+      60: "ERROR",
+      50: "WARN",
+      40: "INFO",
+      30: "CONFIG",
+      20: "DEBUG",
+      10: "TRACE",
+      0:  "ALL"
+    }
+  },
+
+  /**
+   * Create a logger and configure it with dump and console appenders as
+   * specified by prefs based on the logger name.
+   *
+   * E.g., if the loggername is foo, then look for prefs
+   *   foo.logging.console
+   *   foo.logging.dump
+   *
+   * whose values can be empty: no logging of that type; or any of
+   * 'Fatal', 'Error', 'Warn', 'Info', 'Config', 'Debug', 'Trace', 'All',
+   * in which case the logging level for each appender will be set accordingly
+   *
+   * Parameters:
+   *
+   * @param loggername The name of the logger
+   * @param level (optional) the level of the logger itself
+   * @param consoleLevel (optional) the level of the console appender
+   * @param dumpLevel (optional) the level of the dump appender
+   *
+   * As described above, well-named prefs override the last two parameters
+   **/
+
+  getConfiguredLogger: function(loggername, level, consoleLevel, dumpLevel) {
+    let log = Log4Moz.repository.getLogger(loggername);
+    if (log._configured)
+      return log
+
+    let formatter = new Log4Moz.BasicFormatter();
+
+    level = level || Log4Moz.Level.Error;
+
+    consoleLevel = consoleLevel || -1;
+    dumpLevel = dumpLevel || -1;
+    let branch = Services.prefs.getBranch(loggername + ".logging.");
+    if (branch)
+    {
+      try {
+        // figure out if event-driven indexing should be enabled...
+        let consoleLevelString = branch.getCharPref("console");
+        if (consoleLevelString) {
+          // capitalize to fit with Log4Moz.Level expectations
+          consoleLevelString = consoleLevelString.charAt(0).toUpperCase() +
+             consoleLevelString.substr(1).toLowerCase();
+          consoleLevel = (consoleLevelString == 'None') ?
+                          100 : Log4Moz.Level[consoleLevelString];
+        }
+      } catch (ex) {
+        // Ignore if preference is not found
+      }
+      try {
+        let dumpLevelString = branch.getCharPref("dump");
+        if (dumpLevelString) {
+          // capitalize to fit with Log4Moz.Level expectations
+          dumpLevelString = dumpLevelString.charAt(0).toUpperCase() +
+             dumpLevelString.substr(1).toLowerCase();
+          dumpLevel = (dumpLevelString == 'None') ?
+                       100 : Log4Moz.Level[dumpLevelString];
+        }
+      } catch (ex) {
+        // Ignore if preference is not found
+      }
+    }
+
+    if (consoleLevel != 100) {
+      if (consoleLevel == -1)
+        consoleLevel = Log4Moz.Level.Error;
+      let capp = new Log4Moz.ConsoleAppender(formatter);
+      capp.level = consoleLevel;
+      log.addAppender(capp);
+    }
+
+    if (dumpLevel != 100) {
+      if (dumpLevel == -1)
+        dumpLevel = Log4Moz.Level.Error;
+      let dapp = new Log4Moz.DumpAppender(formatter);
+      dapp.level = dumpLevel;
+      log.addAppender(dapp);
+    }
+
+    log.level = Math.min(level, Math.min(consoleLevel, dumpLevel));
+
+    log._configured = true;
+
+    return log;
+  },
+
+  get repository() {
+    delete Log4Moz.repository;
+    Log4Moz.repository = new LoggerRepository();
+    return Log4Moz.repository;
+  },
+  set repository(value) {
+    delete Log4Moz.repository;
+    Log4Moz.repository = value;
+  },
+
+  get LogMessage() { return LogMessage; },
+  get Logger() { return Logger; },
+  get LoggerRepository() { return LoggerRepository; },
+
+  get Formatter() { return Formatter; },
+  get BasicFormatter() { return BasicFormatter; },
+  get XMLFormatter() { return XMLFormatter; },
+  get JSONFormatter() { return JSONFormatter; },
+  get Appender() { return Appender; },
+  get DumpAppender() { return DumpAppender; },
+  get ConsoleAppender() { return ConsoleAppender; },
+  get TimeAwareMemoryBucketAppender() { return TimeAwareMemoryBucketAppender; },
+  get FileAppender() { return FileAppender; },
+  get SocketAppender() { return SocketAppender; },
+  get RotatingFileAppender() { return RotatingFileAppender; },
+  get ThrowingAppender() { return ThrowingAppender; },
+
+  // Logging helper:
+  // let logger = Log4Moz.repository.getLogger("foo");
+  // logger.info(Log4Moz.enumerateInterfaces(someObject).join(","));
+  enumerateInterfaces: function Log4Moz_enumerateInterfaces(aObject) {
+    let interfaces = [];
+
+    for (i in Ci) {
+      try {
+        aObject.QueryInterface(Ci[i]);
+        interfaces.push(i);
+      }
+      catch(ex) {}
+    }
+
+    return interfaces;
+  },
+
+  // Logging helper:
+  // let logger = Log4Moz.repository.getLogger("foo");
+  // logger.info(Log4Moz.enumerateProperties(someObject).join(","));
+  enumerateProperties: function Log4Moz_enumerateProps(aObject,
+                                                       aExcludeComplexTypes) {
+    let properties = [];
+
+    for (var p in aObject) {
+      try {
+        if (aExcludeComplexTypes &&
+            (typeof aObject[p] == "object" || typeof aObject[p] == "function"))
+          continue;
+        properties.push(p + " = " + aObject[p]);
+      }
+      catch(ex) {
+        properties.push(p + " = " + ex);
+      }
+    }
+
+    return properties;
+  }
+};
+
+function LoggerContext() {
+  this._started = this._lastStateChange = Date.now();
+  this._state = "started";
+}
+LoggerContext.prototype = {
+  _jsonMe: true,
+  _id: "unknown",
+  setState: function LoggerContext_state(aState) {
+    this._state = aState;
+    this._lastStateChange = Date.now();
+    return this;
+  },
+  finish: function LoggerContext_finish() {
+    this._finished = Date.now();
+    this._state = "finished";
+    return this;
+  },
+  toString: function LoggerContext_toString() {
+    return "[Context: " + this._id + " state: " + this._state + "]";
+  }
+};
+
+
+/*
+ * LogMessage
+ * Encapsulates a single log event's data
+ */
+function LogMessage(loggerName, level, messageObjects){
+  this.loggerName = loggerName;
+  this.messageObjects = messageObjects;
+  this.level = level;
+  this.time = Date.now();
+}
+LogMessage.prototype = {
+  get levelDesc() {
+    if (this.level in Log4Moz.Level.Desc)
+      return Log4Moz.Level.Desc[this.level];
+    return "UNKNOWN";
+  },
+
+  toString: function LogMsg_toString(){
+    return "LogMessage [" + this.time + " " + this.level + " " +
+      this.messageObjects + "]";
+  }
+};
+
+/*
+ * Logger
+ * Hierarchical version.  Logs to all appenders, assigned or inherited
+ */
+
+function Logger(name, repository) {
+  this._init(name, repository);
+}
+Logger.prototype = {
+  _init: function Logger__init(name, repository) {
+    if (!repository)
+      repository = Log4Moz.repository;
+    this._name = name;
+    this.children = [];
+    this.ownAppenders = [];
+    this.appenders = [];
+    this._repository = repository;
+  },
+
+  get name() {
+    return this._name;
+  },
+
+  _level: null,
+  get level() {
+    if (this._level != null)
+      return this._level;
+    if (this.parent)
+      return this.parent.level;
+    dump("log4moz warning: root logger configuration error: no level defined\n");
+    return Log4Moz.Level.All;
+  },
+  set level(level) {
+    this._level = level;
+  },
+
+  _parent: null,
+  get parent() { return this._parent; },
+  set parent(parent) {
+    if (this._parent == parent) {
+      return;
+    }
+    // Remove ourselves from parent's children
+    if (this._parent) {
+      let index = this._parent.children.indexOf(this);
+      if (index != -1) {
+        this._parent.children.splice(index, 1);
+      }
+    }
+    this._parent = parent;
+    parent.children.push(this);
+    this.updateAppenders();
+  },
+
+  updateAppenders: function updateAppenders() {
+    if (this._parent) {
+      let notOwnAppenders = this._parent.appenders.filter(function(appender) {
+        return this.ownAppenders.indexOf(appender) == -1;
+      }, this);
+      this.appenders = notOwnAppenders.concat(this.ownAppenders);
+    } else {
+      this.appenders = this.ownAppenders.slice();
+    }
+
+    // Update children's appenders.
+    for (let i = 0; i < this.children.length; i++) {
+      this.children[i].updateAppenders();
+    }
+  },
+
+  addAppender: function Logger_addAppender(appender) {
+    if (this.ownAppenders.indexOf(appender) != -1) {
+      return;
+    }
+    this.ownAppenders.push(appender);
+    this.updateAppenders();
+  },
+
+  _nextContextId: 0,
+  newContext: function Logger_newContext(objWithProps) {
+    if (!("_id" in objWithProps))
+      objWithProps._id = this._name + ":" + (++this._nextContextId);
+
+    let c = new LoggerContext();
+    c._isContext = true;
+    for (let key in objWithProps) {
+      c[key] = objWithProps[key];
+    }
+    return c;
+  },
+
+  log: function Logger_log(message) {
+    if (this.level > message.level)
+      return;
+    let appenders = this.appenders;
+    for (let i = 0; i < appenders.length; i++){
+      appenders[i].append(message);
+    }
+  },
+
+  removeAppender: function Logger_removeAppender(appender) {
+    let index = this.ownAppenders.indexOf(appender);
+    if (index == -1) {
+      return;
+    }
+    this.ownAppenders.splice(index, 1);
+    this.updateAppenders();
+  },
+
+  log: function Logger_log(level, args) {
+    if (this.level > level)
+      return;
+
+    // Hold off on creating the message object until we actually have
+    // an appender that's responsible.
+    let message;
+    let appenders = this.appenders;
+    for (let i = 0; i < appenders.length; i++){
+      let appender = appenders[i];
+      if (appender.level > level)
+        continue;
+
+      if (!message)
+        message = new LogMessage(this._name, level,
+                                 Array.prototype.slice.call(args));
+
+      appender.append(message);
+    }
+  },
+
+  fatal: function Logger_fatal() {
+    this.log(Log4Moz.Level.Fatal, arguments);
+  },
+  error: function Logger_error() {
+    this.log(Log4Moz.Level.Error, arguments);
+  },
+  warn: function Logger_warn() {
+    this.log(Log4Moz.Level.Warn, arguments);
+  },
+  info: function Logger_info(string) {
+    this.log(Log4Moz.Level.Info, arguments);
+  },
+  config: function Logger_config(string) {
+    this.log(Log4Moz.Level.Config, arguments);
+  },
+  debug: function Logger_debug(string) {
+    this.log(Log4Moz.Level.Debug, arguments);
+  },
+  trace: function Logger_trace(string) {
+    this.log(Log4Moz.Level.Trace, arguments);
+  }
+};
+
+/*
+ * LoggerRepository
+ * Implements a hierarchy of Loggers
+ */
+
+function LoggerRepository() {}
+LoggerRepository.prototype = {
+  _loggers: {},
+
+  _rootLogger: null,
+  get rootLogger() {
+    if (!this._rootLogger) {
+      this._rootLogger = new Logger("root", this);
+      this._rootLogger.level = Log4Moz.Level.All;
+    }
+    return this._rootLogger;
+  },
+  set rootLogger(logger) {
+    throw "Cannot change the root logger";
+  },
+
+  _updateParents: function LogRep__updateParents(name) {
+    let pieces = name.split('.');
+    let cur, parent;
+
+    // find the closest parent
+    // don't test for the logger name itself, as there's a chance it's already
+    // there in this._loggers
+    for (let i = 0; i < pieces.length - 1; i++) {
+      if (cur)
+        cur += '.' + pieces[i];
+      else
+        cur = pieces[i];
+      if (cur in this._loggers)
+        parent = cur;
+    }
+
+    // if we didn't assign a parent above, there is no parent
+    if (!parent)
+      this._loggers[name].parent = this.rootLogger;
+    else
+      this._loggers[name].parent = this._loggers[parent];
+
+    // trigger updates for any possible descendants of this logger
+    for (let logger in this._loggers) {
+      if (logger != name && logger.indexOf(name) == 0)
+        this._updateParents(logger);
+    }
+  },
+
+  getLogger: function LogRep_getLogger(name) {
+    if (name in this._loggers)
+      return this._loggers[name];
+    this._loggers[name] = new Logger(name, this);
+    this._updateParents(name);
+    return this._loggers[name];
+  }
+};
+
+/*
+ * Formatters
+ * These massage a LogMessage into whatever output is desired
+ * Only the BasicFormatter is currently implemented
+ */
+
+// Abstract formatter
+function Formatter() {}
+Formatter.prototype = {
+  format: function Formatter_format(message) {}
+};
+
+// services' log4moz lost the date formatting default...
+function BasicFormatter(dateFormat) {
+  if (dateFormat)
+    this.dateFormat = dateFormat;
+}
+BasicFormatter.prototype = {
+  __proto__: Formatter.prototype,
+
+  _dateFormat: null,
+
+  get dateFormat() {
+    if (!this._dateFormat)
+      this._dateFormat = "%Y-%m-%d %H:%M:%S";
+    return this._dateFormat;
+  },
+
+  set dateFormat(format) {
+    this._dateFormat = format;
+  },
+
+  format: function BF_format(message) {
+    let date = new Date(message.time);
+    // The trick below prevents errors further down because mo is null or
+    //  undefined.
+    let messageString = message.messageObjects.map(mo => "" + mo).join(" ");
+    return date.toLocaleFormat(this.dateFormat) + "\t" +
+      message.loggerName + "\t" + message.levelDesc + "\t" +
+      messageString + "\n";
+  }
+};
+
+/*
+ * XMLFormatter
+ * Format like log4j's XMLLayout.  The intent is that you can hook this up to
+ * a SocketAppender and point them at a Chainsaw GUI running with an
+ * XMLSocketReceiver running.  Then your output comes out in Chainsaw.
+ * (Chainsaw is log4j's GUI that displays log output with niceties such as
+ * filtering and conditional coloring.)
+ */
+
+function XMLFormatter() {}
+XMLFormatter.prototype = {
+  __proto__: Formatter.prototype,
+
+  format: function XF_format(message) {
+    let cdataEscapedMessage =
+      message.messageObjects
+        .map(mo => (typeof(mo) == "object") ? mo.toString() : mo)
+        .join(" ")
+        .split(CDATA_END).join(CDATA_ESCAPED_END);
+    return "<log4j:event logger='" + message.loggerName + "' " +
+                        "level='" + message.levelDesc + "' thread='unknown' " +
+                        "timestamp='" + message.time + "'>" +
+      "<log4j:message><![CDATA[" + cdataEscapedMessage + "]]></log4j:message>" +
+      "</log4j:event>";
+  }
+};
+
+function JSONFormatter() {
+}
+JSONFormatter.prototype = {
+  __proto__: Formatter.prototype,
+
+  format: function JF_format(message) {
+    // XXX I did all kinds of questionable things in here; they should be
+    //  resolved...
+    // 1) JSON does not walk the __proto__ chain; there is no need to clobber
+    //   it.
+    // 2) Our net mutation is sorta redundant messageObjects alongside
+    //   msgObjects, although we only serialize one.
+    let origMessageObjects = message.messageObjects;
+    message.messageObjects = [];
+    let reProto = [];
+    for (let messageObject of origMessageObjects) {
+      if (messageObject)
+        if (messageObject._jsonMe) {
+          message.messageObjects.push(messageObject);
+// FIXME: the commented out code should be fixed in a better way.
+// See bug 984539: find a good way to avoid JSONing the impl in log4moz
+//          // temporarily strip the prototype to avoid JSONing the impl.
+//          reProto.push([messageObject, messageObject.__proto__]);
+//          messageObject.__proto__ = undefined;
+        }
+        else
+          message.messageObjects.push(messageObject.toString());
+      else
+        message.messageObjects.push(messageObject);
+    }
+    let encoded = JSON.stringify(message) + "\r\n";
+    message.msgObjects = origMessageObjects;
+//    for (let objectAndProtoPair of reProto) {
+//      objectAndProtoPair[0].__proto__ = objectAndProtoPair[1];
+//    }
+    return encoded;
+  }
+};
+
+
+/*
+ * Appenders
+ * These can be attached to Loggers to log to different places
+ * Simply subclass and override doAppend to implement a new one
+ */
+
+function Appender(formatter) {
+  this._name = "Appender";
+  this._formatter = formatter? formatter : new BasicFormatter();
+}
+Appender.prototype = {
+  _level: Log4Moz.Level.All,
+
+  append: function App_append(message) {
+    this.doAppend(this._formatter.format(message));
+  },
+  toString: function App_toString() {
+    return this._name + " [level=" + this._level +
+      ", formatter=" + this._formatter + "]";
+  },
+  doAppend: function App_doAppend(message) {}
+};
+
+/*
+ * DumpAppender
+ * Logs to standard out
+ */
+
+function DumpAppender(formatter) {
+  this._name = "DumpAppender";
+  this._formatter = formatter? formatter : new BasicFormatter();
+}
+DumpAppender.prototype = {
+  __proto__: Appender.prototype,
+
+  doAppend: function DApp_doAppend(message) {
+    dump(message);
+  }
+};
+
+/**
+ * An in-memory appender that always logs to its in-memory bucket and associates
+ * each message with a timestamp.  Whoever creates us is responsible for causing
+ * us to switch to a new bucket using whatever criteria is appropriate.
+ *
+ * This is intended to be used roughly like an in-memory circular buffer.  The
+ * expectation is that we are being used for unit tests and that each unit test
+ * function will get its own bucket.  In the event that a test fails we would
+ * be asked for the contents of the current bucket and some portion of the
+ * previous bucket using up to some duration.
+ */
+function TimeAwareMemoryBucketAppender() {
+  this._name = "TimeAwareMemoryBucketAppender";
+  this._level = Log4Moz.Level.All;
+
+  this._lastBucket = null;
+  // to minimize object construction, even indices are timestamps, odd indices
+  //  are the message objects.
+  this._curBucket = [];
+  this._curBucketStartedAt = Date.now();
+}
+TimeAwareMemoryBucketAppender.prototype = {
+  get level() { return this._level; },
+  set level(level) { this._level = level; },
+
+  append: function TAMBA_append(message) {
+    if (this._level <= message.level)
+      this._curBucket.push(message);
+  },
+
+  newBucket: function() {
+    this._lastBucket = this._curBucket;
+    this._curBucketStartedAt = Date.now();
+    this._curBucket = [];
+  },
+
+  getPreviousBucketEvents: function(aNumMS) {
+    let lastBucket = this._lastBucket;
+    if (lastBucket == null || !lastBucket.length)
+      return [];
+    let timeBound = this._curBucketStartedAt - aNumMS;
+    // seek backwards through the list...
+    let i;
+    for (i = lastBucket.length - 1; i >= 0; i --) {
+      if (lastBucket[i].time < timeBound)
+        break;
+    }
+    return lastBucket.slice(i+1);
+  },
+
+  getBucketEvents: function() {
+    return this._curBucket.concat();
+  },
+
+  toString: function() {
+    return "[TimeAwareMemoryBucketAppender]";
+  },
+};
+
+/*
+ * ConsoleAppender
+ * Logs to the javascript console
+ */
+
+function ConsoleAppender(formatter) {
+  this._name = "ConsoleAppender";
+  this._formatter = formatter;
+}
+ConsoleAppender.prototype = {
+  __proto__: Appender.prototype,
+
+  // override to send Error and higher level messages to Components.utils.reportError()
+  append: function CApp_append(message) {
+    let stringMessage = this._formatter.format(message);
+    if (message.level > Log4Moz.Level.Warn) {
+      Cu.reportError(stringMessage);
+    }
+    this.doAppend(stringMessage);
+  },
+
+  doAppend: function CApp_doAppend(message) {
+    Services.console.logStringMessage(message);
+  }
+};
+
+/*
+ * FileAppender
+ * Logs to a file
+ */
+
+function FileAppender(file, formatter) {
+  this._name = "FileAppender";
+  this._file = file; // nsIFile
+  this._formatter = formatter? formatter : new BasicFormatter();
+}
+FileAppender.prototype = {
+  __proto__: Appender.prototype,
+
+  __fos: null,
+  get _fos() {
+    if (!this.__fos)
+      this.openStream();
+    return this.__fos;
+  },
+
+  openStream: function FApp_openStream() {
+    this.__fos = Cc["@mozilla.org/network/file-output-stream;1"].
+      createInstance(Ci.nsIFileOutputStream);
+    let flags = MODE_WRONLY | MODE_CREATE | MODE_APPEND;
+    this.__fos.init(this._file, flags, PERMS_FILE, 0);
+  },
+
+  closeStream: function FApp_closeStream() {
+    if (!this.__fos)
+      return;
+    try {
+      this.__fos.close();
+      this.__fos = null;
+    } catch(e) {
+      dump("Failed to close file output stream\n" + e);
+    }
+  },
+
+  doAppend: function FApp_doAppend(message) {
+    if (message === null || message.length <= 0)
+      return;
+    try {
+      this._fos.write(message, message.length);
+    } catch(e) {
+      dump("Error writing file:\n" + e);
+    }
+  },
+
+  clear: function FApp_clear() {
+    this.closeStream();
+    this._file.remove(false);
+  }
+};
+
+/*
+ * RotatingFileAppender
+ * Similar to FileAppender, but rotates logs when they become too large
+ */
+
+function RotatingFileAppender(file, formatter, maxSize, maxBackups) {
+  if (maxSize === undefined)
+    maxSize = ONE_MEGABYTE * 2;
+
+  if (maxBackups === undefined)
+    maxBackups = 0;
+
+  this._name = "RotatingFileAppender";
+  this._file = file; // nsIFile
+  this._formatter = formatter? formatter : new BasicFormatter();
+  this._maxSize = maxSize;
+  this._maxBackups = maxBackups;
+}
+RotatingFileAppender.prototype = {
+  __proto__: FileAppender.prototype,
+
+  doAppend: function RFApp_doAppend(message) {
+    if (message === null || message.length <= 0)
+      return;
+    try {
+      this.rotateLogs();
+      this._fos.write(message, message.length);
+    } catch(e) {
+      dump("Error writing file:\n" + e);
+    }
+  },
+  rotateLogs: function RFApp_rotateLogs() {
+    if(this._file.exists() &&
+       this._file.fileSize < this._maxSize)
+      return;
+
+    this.closeStream();
+
+    for (let i = this.maxBackups - 1; i > 0; i--){
+      let backup = this._file.parent.clone();
+      backup.append(this._file.leafName + "." + i);
+      if (backup.exists())
+        backup.moveTo(this._file.parent, this._file.leafName + "." + (i + 1));
+    }
+
+    let cur = this._file.clone();
+    if (cur.exists())
+      cur.moveTo(cur.parent, cur.leafName + ".1");
+
+    // Note: this._file still points to the same file
+  }
+};
+
+/*
+ * SocketAppender
+ * Logs via TCP to a given host and port.  Attempts to automatically reconnect
+ * when the connection drops or cannot be initially re-established.  Connection
+ * attempts will happen at most every timeoutDelay seconds (has a sane default
+ * if left blank).  Messages are dropped when there is no connection.
+ */
+
+function SocketAppender(host, port, formatter, timeoutDelay) {
+  this._name = "SocketAppender";
+  this._host = host;
+  this._port = port;
+  this._formatter = formatter? formatter : new BasicFormatter();
+  this._timeout_delay = timeoutDelay || DEFAULT_NETWORK_TIMEOUT_DELAY;
+
+  this._socketService = Cc["@mozilla.org/network/socket-transport-service;1"]
+                          .getService(Ci.nsISocketTransportService);
+  this._mainThread = Services.tm.mainThread;
+}
+SocketAppender.prototype = {
+  __proto__: Appender.prototype,
+
+  __nos: null,
+  get _nos() {
+    if (!this.__nos)
+      this.openStream();
+    return this.__nos;
+  },
+  _nextCheck: 0,
+  openStream: function SApp_openStream() {
+    let now = Date.now();
+    if (now <= this._nextCheck) {
+      return;
+    }
+    this._nextCheck = now + this._timeout_delay * 1000;
+    try {
+      this._transport = this._socketService.createTransport(
+        null, 0, // default socket type
+        this._host, this._port,
+        null); // no proxy
+      this._transport.setTimeout(Ci.nsISocketTransport.TIMEOUT_CONNECT,
+                                 this._timeout_delay);
+      // do not set a timeout for TIMEOUT_READ_WRITE. The timeout is not
+      //  entirely intuitive; your socket will time out if no one reads or
+      //  writes to the socket within the timeout.  That, as you can imagine,
+      //  is not what we want.
+      this._transport.setEventSink(this, this._mainThread);
+
+      let outputStream = this._transport.openOutputStream(
+        0, // neither blocking nor unbuffered operation is desired
+        0, // default buffer size is fine
+        0 // default buffer count is fine
+        );
+
+      let uniOutputStream = Cc["@mozilla.org/intl/converter-output-stream;1"]
+                              .createInstance(Ci.nsIConverterOutputStream);
+      uniOutputStream.init(outputStream, "utf-8", 0, 0x0000);
+
+      this.__nos = uniOutputStream;
+    } catch (ex) {
+      dump("Unexpected SocketAppender connection problem: " +
+           ex.fileName + ":" + ex.lineNumber + ": " + ex + "\n");
+    }
+  },
+
+  closeStream: function SApp_closeStream() {
+    if (!this._transport)
+      return;
+    try {
+      this._connected = false;
+      this._transport = null;
+      let nos = this.__nos;
+      this.__nos = null;
+      nos.close();
+    } catch(e) {
+      // this shouldn't happen, but no one cares
+    }
+  },
+
+  doAppend: function SApp_doAppend(message) {
+    if (message === null || message.length <= 0)
+      return;
+    try {
+      let nos = this._nos;
+      if (nos)
+        nos.writeString(message);
+    } catch(e) {
+      if (this._transport && !this._transport.isAlive()) {
+        this.closeStream();
+      }
+    }
+  },
+
+  clear: function SApp_clear() {
+    this.closeStream();
+  },
+
+  /* nsITransportEventSink */
+  onTransportStatus: function SApp_onTransportStatus(aTransport, aStatus,
+      aProgress, aProgressMax) {
+    if (aStatus == 0x804b0004) // STATUS_CONNECTED_TO is not a constant.
+      this._connected = true;
+  },
+};
+
+/**
+ * Throws an exception whenever it gets a message.  Intended to be used in
+ * automated testing situations where the code would normally log an error but
+ * not die in a fatal manner.
+ */
+function ThrowingAppender(thrower, formatter) {
+  this._name = "ThrowingAppender";
+  this._formatter = formatter? formatter : new BasicFormatter();
+  this._thrower = thrower;
+}
+ThrowingAppender.prototype = {
+  __proto__: Appender.prototype,
+
+  doAppend: function TApp_doAppend(message) {
+    if (this._thrower)
+      this._thrower(message);
+    else
+      throw message;
+  }
+};