dom/script/ScriptLoader.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_dom_ScriptLoader_h
   8 #define mozilla_dom_ScriptLoader_h
   9
  10 #include "js/TypeDecls.h"
  11 #include "js/loader/LoadedScript.h"
  12 #include "js/loader/ScriptKind.h"
  13 #include "js/loader/ScriptLoadRequest.h"
  14 #include "nsCOMPtr.h"
  15 #include "nsRefPtrHashtable.h"
  16 #include "nsIScriptElement.h"
  17 #include "nsCOMArray.h"
  18 #include "nsCycleCollectionParticipant.h"
  19 #include "nsTArray.h"
  20 #include "nsILoadInfo.h"  // nsSecurityFlags
  21 #include "nsINode.h"
  22 #include "nsIObserver.h"
  23 #include "nsIScriptLoaderObserver.h"
  24 #include "nsURIHashKey.h"
  25 #include "mozilla/CORSMode.h"
  26 #include "mozilla/dom/JSExecutionContext.h"  // JSExecutionContext
  27 #include "ModuleLoader.h"
  28 #include "mozilla/MaybeOneOf.h"
  29 #include "mozilla/MozPromise.h"
  30
  31 class nsCycleCollectionTraversalCallback;
  32 class nsIChannel;
  33 class nsIConsoleReportCollector;
  34 class nsIContent;
  35 class nsIIncrementalStreamLoader;
  36 class nsIPrincipal;
  37 class nsIScriptGlobalObject;
  38 class nsIURI;
  39
  40 namespace JS {
  41
  42 class CompileOptions;
  43
  44 template <typename UnitT>
  45 class SourceText;
  46
  47 namespace loader {
  48
  49 class LoadedScript;
  50 class ScriptLoaderInterface;
  51 class ModuleLoadRequest;
  52 class ModuleScript;
  53 class ScriptLoadRequest;
  54 class ScriptLoadRequestList;
  55
  56 }  // namespace loader
  57 }  // namespace JS
  58
  59 namespace mozilla {
  60
  61 class LazyLogModule;
  62 union Utf8Unit;
  63
  64 namespace dom {
  65
  66 class AutoJSAPI;
  67 class DocGroup;
  68 class Document;
  69 class ModuleLoader;
  70 class SRICheckDataVerifier;
  71 class SRIMetadata;
  72 class ScriptLoadHandler;
  73 class ScriptLoadContext;
  74 class ScriptLoader;
  75 class ScriptRequestProcessor;
  76
  77 enum class ReferrerPolicy : uint8_t;
  78
  79 class AsyncCompileShutdownObserver final : public nsIObserver {
  80   ~AsyncCompileShutdownObserver() { Unregister(); }
  81
  82  public:
  83   explicit AsyncCompileShutdownObserver(ScriptLoader* aLoader)
  84       : mScriptLoader(aLoader) {}
  85
  86   void OnShutdown();
  87   void Unregister();
  88
  89   NS_DECL_ISUPPORTS
  90   NS_DECL_NSIOBSERVER
  91
  92  private:
  93   // Defined during registration in ScriptLoader constructor, and
  94   // cleared during destructor, ScriptLoader::Destroy() or Shutdown.
  95   ScriptLoader* mScriptLoader;
  96 };
  97
  98 //////////////////////////////////////////////////////////////
  99 // Script loader implementation
 100 //////////////////////////////////////////////////////////////
 101
 102 class ScriptLoader final : public JS::loader::ScriptLoaderInterface {
 103   class MOZ_STACK_CLASS AutoCurrentScriptUpdater {
 104    public:
 105     AutoCurrentScriptUpdater(ScriptLoader* aScriptLoader,
 106                              nsIScriptElement* aCurrentScript)
 107         : mOldScript(aScriptLoader->mCurrentScript),
 108           mScriptLoader(aScriptLoader) {
 109       nsCOMPtr<nsINode> node = do_QueryInterface(aCurrentScript);
 110       mScriptLoader->mCurrentScript =
 111           node && !node->IsInShadowTree() ? aCurrentScript : nullptr;
 112     }
 113
 114     ~AutoCurrentScriptUpdater() {
 115       mScriptLoader->mCurrentScript.swap(mOldScript);
 116     }
 117
 118    private:
 119     nsCOMPtr<nsIScriptElement> mOldScript;
 120     ScriptLoader* mScriptLoader;
 121   };
 122
 123   friend class JS::loader::ModuleLoadRequest;
 124   friend class ScriptRequestProcessor;
 125   friend class ModuleLoader;
 126   friend class ScriptLoadHandler;
 127   friend class AutoCurrentScriptUpdater;
 128
 129  public:
 130   explicit ScriptLoader(Document* aDocument);
 131
 132   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
 133   NS_DECL_CYCLE_COLLECTION_CLASS(ScriptLoader)
 134
 135   /**
 136    * The loader maintains a weak reference to the document with
 137    * which it is initialized. This call forces the reference to
 138    * be dropped.
 139    */
 140   void DropDocumentReference() { mDocument = nullptr; }
 141
 142   /**
 143    * Add an observer for all scripts loaded through this loader.
 144    *
 145    * @param aObserver observer for all script processing.
 146    */
 147   nsresult AddObserver(nsIScriptLoaderObserver* aObserver) {
 148     return mObservers.AppendObject(aObserver) ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
 149   }
 150
 151   /**
 152    * Remove an observer.
 153    *
 154    * @param aObserver observer to be removed
 155    */
 156   void RemoveObserver(nsIScriptLoaderObserver* aObserver) {
 157     mObservers.RemoveObject(aObserver);
 158   }
 159
 160   /**
 161    * Process a script element. This will include both loading the
 162    * source of the element if it is not inline and evaluating
 163    * the script itself.
 164    *
 165    * If the script is an inline script that can be executed immediately
 166    * (i.e. there are no other scripts pending) then ScriptAvailable
 167    * and ScriptEvaluated will be called before the function returns.
 168    *
 169    * If true is returned the script could not be executed immediately.
 170    * In this case ScriptAvailable is guaranteed to be called at a later
 171    * point (as well as possibly ScriptEvaluated).
 172    *
 173    * @param aElement The element representing the script to be loaded and
 174    *        evaluated.
 175    */
 176   bool ProcessScriptElement(nsIScriptElement* aElement);
 177
 178   /**
 179    * Gets the currently executing script. This is useful if you want to
 180    * generate a unique key based on the currently executing script.
 181    */
 182   nsIScriptElement* GetCurrentScript() { return mCurrentScript; }
 183
 184   nsIScriptElement* GetCurrentParserInsertedScript() {
 185     return mCurrentParserInsertedScript;
 186   }
 187
 188   /**
 189    * Whether the loader is enabled or not.
 190    * When disabled, processing of new script elements is disabled.
 191    * Any call to ProcessScriptElement() will return false. Note that
 192    * this DOES NOT disable currently loading or executing scripts.
 193    */
 194   bool GetEnabled() { return mEnabled; }
 195
 196   void SetEnabled(bool aEnabled) {
 197     if (!mEnabled && aEnabled) {
 198       ProcessPendingRequestsAsync();
 199     }
 200     mEnabled = aEnabled;
 201   }
 202
 203   ModuleLoader* GetModuleLoader() { return mModuleLoader; }
 204
 205   /**
 206    *  Check whether to speculatively OMT parse scripts as soon as
 207    *  they are fetched, even if not a parser blocking request.
 208    *  Controlled by
 209    *  dom.script_loader.external_scripts.speculative_omt_parse_enabled
 210    */
 211   bool SpeculativeOMTParsingEnabled() const {
 212     return mSpeculativeOMTParsingEnabled;
 213   }
 214
 215   /**
 216    * Add/remove a blocker for parser-blocking scripts (and XSLT
 217    * scripts). Blockers will stop such scripts from executing, but not from
 218    * loading.
 219    */
 220   void AddParserBlockingScriptExecutionBlocker() {
 221     ++mParserBlockingBlockerCount;
 222   }
 223
 224   void RemoveParserBlockingScriptExecutionBlocker() {
 225     if (!--mParserBlockingBlockerCount && ReadyToExecuteScripts()) {
 226       ProcessPendingRequestsAsync();
 227     }
 228   }
 229
 230   /**
 231    * Add/remove a blocker for execution of all scripts.  Blockers will stop
 232    * scripts from executing, but not from loading.
 233    */
 234   void AddExecuteBlocker() { ++mBlockerCount; }
 235
 236   void RemoveExecuteBlocker() {
 237     MOZ_ASSERT(mBlockerCount);
 238     if (!--mBlockerCount) {
 239       ProcessPendingRequestsAsync();
 240     }
 241   }
 242
 243   /**
 244    * Convert the given buffer to a UTF-16 string.  If the buffer begins with a
 245    * BOM, it is interpreted as that encoding; otherwise the first of |aChannel|,
 246    * |aHintCharset|, or |aDocument| that provides a recognized encoding is used,
 247    * or Windows-1252 if none of them do.
 248    *
 249    * Encoding errors in the buffer are converted to replacement characters, so
 250    * allocation failure is the only way this function can fail.
 251    *
 252    * @param aChannel     Channel corresponding to the data. May be null.
 253    * @param aData        The data to convert
 254    * @param aLength      Length of the data
 255    * @param aHintCharset Character set hint (e.g., from a charset attribute).
 256    * @param aDocument    Document which the data is loaded for. May be null.
 257    * @param aBufOut      [out] fresh char16_t array containing data converted to
 258    *                     Unicode.  Caller must js_free() this data when finished
 259    *                     with it.
 260    * @param aLengthOut   [out] Length of array returned in aBufOut in number
 261    *                     of char16_t code units.
 262    */
 263   static nsresult ConvertToUTF16(nsIChannel* aChannel, const uint8_t* aData,
 264                                  uint32_t aLength,
 265                                  const nsAString& aHintCharset,
 266                                  Document* aDocument, char16_t*& aBufOut,
 267                                  size_t& aLengthOut);
 268
 269   static inline nsresult ConvertToUTF16(nsIChannel* aChannel,
 270                                         const uint8_t* aData, uint32_t aLength,
 271                                         const nsAString& aHintCharset,
 272                                         Document* aDocument,
 273                                         JS::UniqueTwoByteChars& aBufOut,
 274                                         size_t& aLengthOut) {
 275     char16_t* bufOut;
 276     nsresult rv = ConvertToUTF16(aChannel, aData, aLength, aHintCharset,
 277                                  aDocument, bufOut, aLengthOut);
 278     if (NS_SUCCEEDED(rv)) {
 279       aBufOut.reset(bufOut);
 280     }
 281     return rv;
 282   };
 283
 284   /**
 285    * Convert the given buffer to a UTF-8 string.  If the buffer begins with a
 286    * BOM, it is interpreted as that encoding; otherwise the first of |aChannel|,
 287    * |aHintCharset|, or |aDocument| that provides a recognized encoding is used,
 288    * or Windows-1252 if none of them do.
 289    *
 290    * Encoding errors in the buffer are converted to replacement characters, so
 291    * allocation failure is the only way this function can fail.
 292    *
 293    * @param aChannel     Channel corresponding to the data. May be null.
 294    * @param aData        The data to convert
 295    * @param aLength      Length of the data
 296    * @param aHintCharset Character set hint (e.g., from a charset attribute).
 297    * @param aDocument    Document which the data is loaded for. May be null.
 298    * @param aBufOut      [out] fresh Utf8Unit array containing data converted to
 299    *                     Unicode.  Caller must js_free() this data when finished
 300    *                     with it.
 301    * @param aLengthOut   [out] Length of array returned in aBufOut in UTF-8 code
 302    *                     units (i.e. in bytes).
 303    */
 304   static nsresult ConvertToUTF8(nsIChannel* aChannel, const uint8_t* aData,
 305                                 uint32_t aLength, const nsAString& aHintCharset,
 306                                 Document* aDocument, Utf8Unit*& aBufOut,
 307                                 size_t& aLengthOut);
 308
 309   /**
 310    * Handle the completion of a stream.  This is called by the
 311    * ScriptLoadHandler object which observes the IncrementalStreamLoader
 312    * loading the script. The streamed content is expected to be stored on the
 313    * aRequest argument.
 314    */
 315   nsresult OnStreamComplete(nsIIncrementalStreamLoader* aLoader,
 316                             ScriptLoadRequest* aRequest,
 317                             nsresult aChannelStatus, nsresult aSRIStatus,
 318                             SRICheckDataVerifier* aSRIDataVerifier);
 319
 320   /**
 321    * Returns wether any request is queued, and not executed yet.
 322    */
 323   bool HasPendingRequests();
 324
 325   /**
 326    * Processes any pending requests that are ready for processing.
 327    */
 328   void ProcessPendingRequests();
 329
 330   /**
 331    * Starts deferring deferred scripts and puts them in the mDeferredRequests
 332    * queue instead.
 333    */
 334   void BeginDeferringScripts();
 335
 336   /**
 337    * Notifies the script loader that parsing is done.  If aTerminated is true,
 338    * this will drop any pending scripts that haven't run yet, otherwise it will
 339    * do nothing.
 340    */
 341   void ParsingComplete(bool aTerminated);
 342
 343   /**
 344    * Notifies the script loader that the checkpoint to begin execution of defer
 345    * scripts has been reached. This is either the end of of the document parse
 346    * or the end of loading of parser-inserted stylesheets, whatever happens
 347    * last.
 348    *
 349    * Otherwise, it will stop deferring scripts and immediately processes the
 350    * mDeferredRequests queue.
 351    *
 352    * WARNING: This function will synchronously execute content scripts, so be
 353    * prepared that the world might change around you.
 354    */
 355   void DeferCheckpointReached();
 356
 357   /**
 358    * Returns the number of pending scripts, deferred or not.
 359    */
 360   uint32_t HasPendingOrCurrentScripts() {
 361     return mCurrentScript || mParserBlockingRequest;
 362   }
 363
 364   /**
 365    * Adds aURI to the preload list and starts loading it.
 366    *
 367    * @param aURI The URI of the external script.
 368    * @param aCharset The charset parameter for the script.
 369    * @param aType The type parameter for the script.
 370    * @param aCrossOrigin The crossorigin attribute for the script.
 371    *                     Void if not present.
 372    * @param aIntegrity The expect hash url, if avail, of the request
 373    * @param aScriptFromHead Whether or not the script was a child of head
 374    */
 375   virtual void PreloadURI(nsIURI* aURI, const nsAString& aCharset,
 376                           const nsAString& aType, const nsAString& aCrossOrigin,
 377                           const nsAString& aIntegrity, bool aScriptFromHead,
 378                           bool aAsync, bool aDefer, bool aNoModule,
 379                           bool aLinkPreload,
 380                           const ReferrerPolicy aReferrerPolicy);
 381
 382   /**
 383    * Process a request that was deferred so that the script could be compiled
 384    * off thread.
 385    */
 386   nsresult ProcessOffThreadRequest(ScriptLoadRequest* aRequest);
 387
 388   bool AddPendingChildLoader(ScriptLoader* aChild) {
 389     // XXX(Bug 1631371) Check if this should use a fallible operation as it
 390     // pretended earlier. Else, change the return type to void.
 391     mPendingChildLoaders.AppendElement(aChild);
 392     return true;
 393   }
 394
 395   mozilla::dom::DocGroup* GetDocGroup() const;
 396
 397   /**
 398    * Register the fact that we saw the load event, and that we need to save the
 399    * bytecode at the next loop cycle unless new scripts are waiting in the
 400    * pipeline.
 401    */
 402   void LoadEventFired();
 403
 404   /**
 405    * Destroy and prevent the ScriptLoader or the ScriptLoadRequests from owning
 406    * any references to the JSScript or to the Request which might be used for
 407    * caching the encoded bytecode.
 408    */
 409   void Destroy();
 410
 411   /*
 412    * Get the currently active script. This is used as the initiating script when
 413    * executing timeout handler scripts.
 414    */
 415   static JS::loader::LoadedScript* GetActiveScript(JSContext* aCx);
 416
 417   Document* GetDocument() const { return mDocument; }
 418
 419   nsIURI* GetBaseURI() const override;
 420
 421  private:
 422   virtual ~ScriptLoader();
 423
 424   already_AddRefed<ScriptLoadRequest> CreateLoadRequest(
 425       ScriptKind aKind, nsIURI* aURI, nsIScriptElement* aElement,
 426       nsIPrincipal* aTriggeringPrincipal, mozilla::CORSMode aCORSMode,
 427       const SRIMetadata& aIntegrity, ReferrerPolicy aReferrerPolicy);
 428
 429   /**
 430    * Unblocks the creator parser of the parser-blocking scripts.
 431    */
 432   void UnblockParser(ScriptLoadRequest* aParserBlockingRequest);
 433
 434   /**
 435    * Asynchronously resumes the creator parser of the parser-blocking scripts.
 436    */
 437   void ContinueParserAsync(ScriptLoadRequest* aParserBlockingRequest);
 438
 439   bool ProcessExternalScript(nsIScriptElement* aElement, ScriptKind aScriptKind,
 440                              const nsAutoString& aTypeAttr,
 441                              nsIContent* aScriptContent);
 442
 443   bool ProcessInlineScript(nsIScriptElement* aElement, ScriptKind aScriptKind);
 444
 445   JS::loader::ScriptLoadRequest* LookupPreloadRequest(
 446       nsIScriptElement* aElement, ScriptKind aScriptKind,
 447       const SRIMetadata& aSRIMetadata);
 448
 449   void GetSRIMetadata(const nsAString& aIntegrityAttr,
 450                       SRIMetadata* aMetadataOut);
 451
 452   /**
 453    * Given a script element, get the referrer policy should be applied to load
 454    * requests.
 455    */
 456   ReferrerPolicy GetReferrerPolicy(nsIScriptElement* aElement);
 457
 458   /**
 459    * Helper function to check the content policy for a given request.
 460    */
 461   static nsresult CheckContentPolicy(Document* aDocument, nsISupports* aContext,
 462                                      const nsAString& aType,
 463                                      ScriptLoadRequest* aRequest);
 464
 465   /**
 466    * Helper function to determine whether an about: page loads a chrome: URI.
 467    * Please note that this function only returns true if:
 468    *   * the about: page uses a ContentPrincipal with scheme about:
 469    *   * the about: page is not linkable from content
 470    *     (e.g. the function will return false for about:blank or about:srcdoc)
 471    */
 472   static bool IsAboutPageLoadingChromeURI(ScriptLoadRequest* aRequest,
 473                                           Document* aDocument);
 474
 475   /**
 476    * Start a load for aRequest's URI.
 477    */
 478   nsresult StartLoad(ScriptLoadRequest* aRequest);
 479   /**
 480    * Start a load for a classic script URI.
 481    * Sets up the necessary security flags before calling StartLoadInternal.
 482    */
 483   nsresult StartClassicLoad(ScriptLoadRequest* aRequest);
 484
 485   /**
 486    * Start a load for a module script URI.
 487    */
 488   nsresult StartLoadInternal(ScriptLoadRequest* aRequest,
 489                              nsSecurityFlags securityFlags);
 490
 491   /**
 492    * Abort the current stream, and re-start with a new load request from scratch
 493    * without requesting any alternate data. Returns NS_BINDING_RETARGETED on
 494    * success, as this error code is used to abort the input stream.
 495    */
 496   nsresult RestartLoad(ScriptLoadRequest* aRequest);
 497
 498   void HandleLoadError(ScriptLoadRequest* aRequest, nsresult aResult);
 499
 500   /**
 501    * Process any pending requests asynchronously (i.e. off an event) if there
 502    * are any. Note that this is a no-op if there aren't any currently pending
 503    * requests.
 504    *
 505    * This function is virtual to allow cross-library calls to SetEnabled()
 506    */
 507   virtual void ProcessPendingRequestsAsync();
 508
 509   /**
 510    * If true, the loader is ready to execute parser-blocking scripts, and so are
 511    * all its ancestors.  If the loader itself is ready but some ancestor is not,
 512    * this function will add an execute blocker and ask the ancestor to remove it
 513    * once it becomes ready.
 514    */
 515   bool ReadyToExecuteParserBlockingScripts();
 516
 517   /**
 518    * Return whether just this loader is ready to execute parser-blocking
 519    * scripts.
 520    */
 521   bool SelfReadyToExecuteParserBlockingScripts() {
 522     return ReadyToExecuteScripts() && !mParserBlockingBlockerCount;
 523   }
 524
 525   /**
 526    * Return whether this loader is ready to execute scripts in general.
 527    */
 528   bool ReadyToExecuteScripts() { return mEnabled && !mBlockerCount; }
 529
 530   nsresult VerifySRI(ScriptLoadRequest* aRequest,
 531                      nsIIncrementalStreamLoader* aLoader, nsresult aSRIStatus,
 532                      SRICheckDataVerifier* aSRIDataVerifier) const;
 533
 534   nsresult SaveSRIHash(ScriptLoadRequest* aRequest,
 535                        SRICheckDataVerifier* aSRIDataVerifier,
 536                        uint32_t* sriLength) const;
 537
 538   void ReportErrorToConsole(ScriptLoadRequest* aRequest,
 539                             nsresult aResult) const override;
 540   void ReportPreloadErrorsToConsole(ScriptLoadRequest* aRequest);
 541
 542   nsresult AttemptAsyncScriptCompile(ScriptLoadRequest* aRequest,
 543                                      bool* aCouldCompileOut);
 544   nsresult ProcessRequest(ScriptLoadRequest* aRequest);
 545   nsresult CompileOffThreadOrProcessRequest(ScriptLoadRequest* aRequest);
 546   void FireScriptAvailable(nsresult aResult, ScriptLoadRequest* aRequest);
 547   // TODO: Convert this to MOZ_CAN_RUN_SCRIPT (bug 1415230)
 548   MOZ_CAN_RUN_SCRIPT_BOUNDARY void FireScriptEvaluated(
 549       nsresult aResult, ScriptLoadRequest* aRequest);
 550
 551   // Implements https://html.spec.whatwg.org/#execute-the-script-block
 552   nsresult EvaluateScriptElement(ScriptLoadRequest* aRequest);
 553
 554   // Handles both bytecode and text source scripts; populates exec with a
 555   // compiled script
 556   nsresult CompileOrDecodeClassicScript(JSContext* aCx,
 557                                         JSExecutionContext& aExec,
 558                                         ScriptLoadRequest* aRequest);
 559
 560   nsresult MaybePrepareForBytecodeEncoding(JS::Handle<JSScript*> aScript,
 561                                            ScriptLoadRequest* aRequest,
 562                                            nsresult aRv);
 563
 564   // Implements https://html.spec.whatwg.org/#run-a-classic-script
 565   nsresult EvaluateScript(nsIGlobalObject* aGlobalObject,
 566                           ScriptLoadRequest* aRequest);
 567
 568   /**
 569    * Queue the current script load request to be saved, when the page
 570    * initialization ends. The page initialization end is defined as being the
 571    * time when the load event got received, and when no more scripts are waiting
 572    * to be executed.
 573    */
 574   void RegisterForBytecodeEncoding(ScriptLoadRequest* aRequest);
 575
 576   /**
 577    * Check if all conditions are met, i-e that the onLoad event fired and that
 578    * no more script have to be processed.  If all conditions are met, queue an
 579    * event to encode all the bytecode and save them on the cache.
 580    */
 581   void MaybeTriggerBytecodeEncoding();
 582
 583   /**
 584    * Iterate over all script load request and save the bytecode of executed
 585    * functions on the cache provided by the channel.
 586    */
 587   void EncodeBytecode();
 588   void EncodeRequestBytecode(JSContext* aCx, ScriptLoadRequest* aRequest);
 589
 590   void GiveUpBytecodeEncoding();
 591
 592   already_AddRefed<nsIGlobalObject> GetGlobalForRequest(
 593       ScriptLoadRequest* aRequest) override;
 594
 595   // This is a marker class to ensure proper handling of requests with a
 596   // WebExtGlobal.
 597   enum class WebExtGlobal { Ignore, Handled };
 598
 599   already_AddRefed<nsIScriptGlobalObject> GetScriptGlobalObject(
 600       WebExtGlobal aWebExtGlobal);
 601
 602   // Fill in CompileOptions, as well as produce the introducer script for
 603   // subsequent calls to UpdateDebuggerMetadata
 604   nsresult FillCompileOptionsForRequest(
 605       JSContext* aCx, ScriptLoadRequest* aRequest,
 606       JS::Handle<JSObject*> aScopeChain, JS::CompileOptions* aOptions,
 607       JS::MutableHandle<JSScript*> aIntroductionScript) override;
 608
 609   uint32_t NumberOfProcessors();
 610   int32_t PhysicalSizeOfMemoryInGB();
 611
 612   nsresult PrepareLoadedRequest(ScriptLoadRequest* aRequest,
 613                                 nsIIncrementalStreamLoader* aLoader,
 614                                 nsresult aStatus);
 615
 616   void AddDeferRequest(ScriptLoadRequest* aRequest);
 617   void AddAsyncRequest(ScriptLoadRequest* aRequest);
 618   bool MaybeRemovedDeferRequests();
 619
 620   bool ShouldFullParse(ScriptLoadRequest* aRequest);
 621   bool ShouldCompileOffThread(ScriptLoadRequest* aRequest);
 622
 623   void MaybeMoveToLoadedList(ScriptLoadRequest* aRequest);
 624
 625   using MaybeSourceText =
 626       mozilla::MaybeOneOf<JS::SourceText<char16_t>, JS::SourceText<Utf8Unit>>;
 627
 628   // Returns wether we should save the bytecode of this script after the
 629   // execution of the script.
 630   static bool ShouldCacheBytecode(ScriptLoadRequest* aRequest);
 631
 632   void RunScriptWhenSafe(ScriptLoadRequest* aRequest);
 633
 634   /**
 635    *  Wait for any unused off thread compilations to finish and then
 636    *  cancel them.
 637    */
 638   void CancelScriptLoadRequests();
 639
 640   Document* mDocument;  // [WEAK]
 641   nsCOMArray<nsIScriptLoaderObserver> mObservers;
 642   ScriptLoadRequestList mNonAsyncExternalScriptInsertedRequests;
 643   // mLoadingAsyncRequests holds async requests while they're loading; when they
 644   // have been loaded they are moved to mLoadedAsyncRequests.
 645   ScriptLoadRequestList mLoadingAsyncRequests;
 646   ScriptLoadRequestList mLoadedAsyncRequests;
 647   ScriptLoadRequestList mDeferRequests;
 648   ScriptLoadRequestList mXSLTRequests;
 649   RefPtr<ScriptLoadRequest> mParserBlockingRequest;
 650   ScriptLoadRequestList mOffThreadCompilingRequests;
 651
 652   // List of script load request that are holding a buffer which has to be saved
 653   // on the cache.
 654   ScriptLoadRequestList mBytecodeEncodingQueue;
 655
 656   // In mRequests, the additional information here is stored by the element.
 657   struct PreloadInfo {
 658     RefPtr<ScriptLoadRequest> mRequest;
 659     nsString mCharset;
 660   };
 661
 662   friend void ImplCycleCollectionUnlink(ScriptLoader::PreloadInfo& aField);
 663   friend void ImplCycleCollectionTraverse(
 664       nsCycleCollectionTraversalCallback& aCallback,
 665       ScriptLoader::PreloadInfo& aField, const char* aName, uint32_t aFlags);
 666
 667   struct PreloadRequestComparator {
 668     bool Equals(const PreloadInfo& aPi,
 669                 ScriptLoadRequest* const& aRequest) const {
 670       return aRequest == aPi.mRequest;
 671     }
 672   };
 673
 674   struct PreloadURIComparator {
 675     bool Equals(const PreloadInfo& aPi, nsIURI* const& aURI) const;
 676   };
 677
 678   nsTArray<PreloadInfo> mPreloads;
 679
 680   nsCOMPtr<nsIScriptElement> mCurrentScript;
 681   nsCOMPtr<nsIScriptElement> mCurrentParserInsertedScript;
 682   nsTArray<RefPtr<ScriptLoader>> mPendingChildLoaders;
 683   uint32_t mParserBlockingBlockerCount;
 684   uint32_t mBlockerCount;
 685   uint32_t mNumberOfProcessors;
 686   uint32_t mTotalFullParseSize;
 687   int32_t mPhysicalSizeOfMemory;
 688   bool mEnabled;
 689   bool mDeferEnabled;
 690   bool mSpeculativeOMTParsingEnabled;
 691   bool mDeferCheckpointReached;
 692   bool mBlockingDOMContentLoaded;
 693   bool mLoadEventFired;
 694   bool mGiveUpEncoding;
 695
 696   TimeDuration mMainThreadParseTime;
 697
 698   nsCOMPtr<nsIConsoleReportCollector> mReporter;
 699
 700   // ShutdownObserver for off thread compilations
 701   RefPtr<AsyncCompileShutdownObserver> mShutdownObserver;
 702
 703   RefPtr<ModuleLoader> mModuleLoader;
 704
 705   // Logging
 706  public:
 707   static LazyLogModule gCspPRLog;
 708   static LazyLogModule gScriptLoaderLog;
 709 };
 710
 711 class nsAutoScriptLoaderDisabler {
 712  public:
 713   explicit nsAutoScriptLoaderDisabler(Document* aDoc);
 714
 715   ~nsAutoScriptLoaderDisabler();
 716
 717   bool mWasEnabled;
 718   RefPtr<ScriptLoader> mLoader;
 719 };
 720
 721 }  // namespace dom
 722 }  // namespace mozilla
 723
 724 #endif  // mozilla_dom_ScriptLoader_h