michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsISupports.idl"
michael@0: 
michael@0: interface nsIVisualEventTracerLog;
michael@0: 
michael@0: /**
michael@0:  * Interface to control the visual event tracer feature.  The result
michael@0:  * is a log of various events that are monitored by a custom code
michael@0:  * instrumentation around the mozilla code base.
michael@0:  */
michael@0: 
michael@0: [builtinclass, scriptable, uuid(713ee3ca-95e0-4085-8616-f6d64a9508ad)]
michael@0: interface nsIVisualEventTracer : nsISupports
michael@0: {
michael@0:   /**
michael@0:    * Start the logging now.  No affect if already started.
michael@0:    * Current backlog is deleted by this call otherwise.
michael@0:    *
michael@0:    * @param minBacklogSeconds
michael@0:    *    Manimum time to keep the backlog.  Entries of the log are discarded
michael@0:    *    when their age is more then value of this argument.
michael@0:    */
michael@0:   void start(in unsigned long minBacklogSeconds);
michael@0: 
michael@0:   /**
michael@0:    * Stop the logging now.  Backlog is kept in memory.
michael@0:    */
michael@0:   void stop();
michael@0: 
michael@0:   /**
michael@0:    * Obtain the log.  This can be called whenever you want.
michael@0:    *
michael@0:    * @return
michael@0:    *    Result is an object that keeps snaphot of the log from
michael@0:    *    time this method has been called.  You can then access
michael@0:    *    the log using the object.  Calling stop() on the tracer
michael@0:    *    doesn't delete this log.
michael@0:    */
michael@0:   nsIVisualEventTracerLog snapshot();
michael@0: };
michael@0: 
michael@0: [builtinclass, scriptable, uuid(8ec6e36d-6cba-400b-bcd6-454679f5f75a)]
michael@0: interface nsIVisualEventTracerLog : nsISupports
michael@0: {
michael@0:   /**
michael@0:    * JSON string of the log.  Use JSON.parse to get it as an object.
michael@0:    */
michael@0:   readonly attribute ACString JSONString;
michael@0: 
michael@0:   /**
michael@0:    * Write the JSON string returned by JSONString to the log defined by
michael@0:    * the environment variable MOZ_PROFILING_FILE.
michael@0:    */
michael@0:   void writeToProfilingFile();
michael@0: };