dom/src/threads/nsDOMWorkerScriptLoader.h

   1 /* -*- Mode: c++; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 40 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is worker threads.
  16  *
  17  * The Initial Developer of the Original Code is
  18  *   Mozilla Corporation.
  19  * Portions created by the Initial Developer are Copyright (C) 2008
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Ben Turner <bent.mozilla@gmail.com> (Original Author)
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either the GNU General Public License Version 2 or later (the "GPL"), or
  27  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  28  * in which case the provisions of the GPL or the LGPL are applicable instead
  29  * of those above. If you wish to allow use of your version of this file only
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  34  * the provisions above, a recipient may use your version of this file under
  35  * the terms of any one of the MPL, the GPL or the LGPL.
  36  *
  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #ifndef __NSDOMWORKERSCRIPTLOADER_H__
  40 #define __NSDOMWORKERSCRIPTLOADER_H__
  41
  42 // Bases
  43 #include "nsIRunnable.h"
  44 #include "nsIStreamLoader.h"
  45
  46 // Interfaces
  47 #include "nsIChannel.h"
  48 #include "nsIURI.h"
  49
  50 // Other includes
  51 #include "jsapi.h"
  52 #include "nsAutoPtr.h"
  53 #include "nsAutoJSValHolder.h"
  54 #include "nsCOMPtr.h"
  55 #include "nsStringGlue.h"
  56 #include "nsTArray.h"
  57 #include "prlock.h"
  58
  59 #include "nsDOMWorker.h"
  60
  61 class nsIThread;
  62
  63 /**
  64  * This class takes a list of script URLs, downloads the scripts, compiles the
  65  * scripts, and then finally executes them. Due to platform limitations all
  66  * network operations must happen on the main thread so this object sends events
  67  * back and forth from the worker thread to the main thread. The flow goes like
  68  * this:
  69  *
  70  *  1. (Worker thread) nsDOMWorkerScriptLoader created.
  71  *  2. (Worker thread) LoadScript(s) called. Some simple argument validation is
  72  *                     performed (currently limited to ensuring that all
  73  *                     arguments are strings). nsDOMWorkerScriptLoader is then
  74  *                     dispatched to the main thread.
  75  *  3. (Main thread)   Arguments validated as URIs, security checks performed,
  76  *                     content policy consulted. Network loads begin.
  77  *  4. (Necko thread)  Necko stuff!
  78  *  5. (Main thread)   Completed downloads are packaged in a ScriptCompiler
  79  *                     runnable and sent to the worker thread.
  80  *  6. (Worker thread) ScriptCompiler runnables are processed (i.e. their
  81  *                     scripts are compiled) in the order in which the necko
  82  *                     downloads completed.
  83  *  7. (Worker thread) After all loads complete and all compilation succeeds
  84  *                     the scripts are executed in the order that the URLs were
  85  *                     given to LoadScript(s).
  86  *
  87  * Currently if *anything* after 2 fails then we cancel any pending loads and
  88  * bail out entirely.
  89  */
  90 class nsDOMWorkerScriptLoader : public nsDOMWorkerFeature,
  91                                 public nsIRunnable,
  92                                 public nsIStreamLoaderObserver
  93 {
  94   friend class AutoSuspendWorkerEvents;
  95   friend class ScriptLoaderRunnable;
  96
  97 public:
  98   NS_DECL_ISUPPORTS_INHERITED
  99   NS_DECL_NSIRUNNABLE
 100   NS_DECL_NSISTREAMLOADEROBSERVER
 101
 102   nsDOMWorkerScriptLoader(nsDOMWorker* aWorker);
 103
 104   nsresult LoadScripts(JSContext* aCx,
 105                        const nsTArray<nsString>& aURLs,
 106                        PRBool aForWorker);
 107
 108   nsresult LoadScript(JSContext* aCx,
 109                       const nsString& aURL,
 110                       PRBool aForWorker);
 111
 112   virtual void Cancel();
 113
 114 private:
 115   ~nsDOMWorkerScriptLoader() { }
 116
 117
 118   nsresult DoRunLoop(JSContext* aCx);
 119   nsresult VerifyScripts(JSContext* aCx);
 120   nsresult ExecuteScripts(JSContext* aCx);
 121
 122   nsresult RunInternal();
 123
 124   nsresult OnStreamCompleteInternal(nsIStreamLoader* aLoader,
 125                                     nsISupports* aContext,
 126                                     nsresult aStatus,
 127                                     PRUint32 aStringLen,
 128                                     const PRUint8* aString);
 129
 130   void NotifyDone();
 131
 132   void SuspendWorkerEvents();
 133   void ResumeWorkerEvents();
 134
 135   PRLock* Lock() {
 136     return mWorker->Lock();
 137   }
 138
 139   class ScriptLoaderRunnable : public nsIRunnable
 140   {
 141   public:
 142     NS_DECL_ISUPPORTS
 143
 144   protected:
 145     // Meant to be inherited.
 146     ScriptLoaderRunnable(nsDOMWorkerScriptLoader* aLoader);
 147     virtual ~ScriptLoaderRunnable();
 148
 149   public:
 150     void Revoke();
 151
 152   protected:
 153     PRBool mRevoked;
 154
 155   private:
 156     nsDOMWorkerScriptLoader* mLoader;
 157   };
 158
 159   class ScriptCompiler : public ScriptLoaderRunnable
 160   {
 161   public:
 162     NS_DECL_NSIRUNNABLE
 163
 164     ScriptCompiler(nsDOMWorkerScriptLoader* aLoader,
 165                    const nsString& aScriptText,
 166                    const nsCString& aFilename,
 167                    nsAutoJSValHolder& aScriptObj);
 168
 169   private:
 170     nsString mScriptText;
 171     nsCString mFilename;
 172     nsAutoJSValHolder& mScriptObj;
 173   };
 174
 175   class ScriptLoaderDone : public ScriptLoaderRunnable
 176   {
 177   public:
 178     NS_DECL_NSIRUNNABLE
 179
 180     ScriptLoaderDone(nsDOMWorkerScriptLoader* aLoader,
 181                      volatile PRBool* aDoneFlag);
 182
 183   private:
 184     volatile PRBool* mDoneFlag;
 185   };
 186
 187   class AutoSuspendWorkerEvents
 188   {
 189   public:
 190     AutoSuspendWorkerEvents(nsDOMWorkerScriptLoader* aLoader);
 191     ~AutoSuspendWorkerEvents();
 192
 193   private:
 194     nsDOMWorkerScriptLoader* mLoader;
 195   };
 196
 197   struct ScriptLoadInfo
 198   {
 199     ScriptLoadInfo() : done(PR_FALSE), result(NS_ERROR_NOT_INITIALIZED) { }
 200
 201     nsString url;
 202     nsString scriptText;
 203     PRBool done;
 204     nsresult result;
 205     nsCOMPtr<nsIURI> finalURI;
 206     nsCOMPtr<nsIChannel> channel;
 207     nsAutoJSValHolder scriptObj;
 208   };
 209
 210   nsIThread* mTarget;
 211
 212   nsRefPtr<ScriptLoaderDone> mDoneRunnable;
 213
 214   PRUint32 mScriptCount;
 215   nsTArray<ScriptLoadInfo> mLoadInfos;
 216
 217   // Protected by mWorker's lock!
 218   nsTArray<ScriptLoaderRunnable*> mPendingRunnables;
 219
 220   PRPackedBool mCanceled;
 221   PRPackedBool mForWorker;
 222 };
 223
 224 #endif /* __NSDOMWORKERSCRIPTLOADER_H__ */