js/loader/ModuleLoadRequest.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 js_loader_ModuleLoadRequest_h
   8 #define js_loader_ModuleLoadRequest_h
   9
  10 #include "LoadContextBase.h"
  11 #include "ScriptLoadRequest.h"
  12 #include "ModuleLoaderBase.h"
  13 #include "mozilla/Assertions.h"
  14 #include "js/RootingAPI.h"
  15 #include "js/Value.h"
  16 #include "nsURIHashKey.h"
  17 #include "nsTHashtable.h"
  18
  19 namespace JS::loader {
  20
  21 class ModuleScript;
  22 class ModuleLoaderBase;
  23
  24 // A reference counted set of URLs we have visited in the process of loading a
  25 // module graph.
  26 class VisitedURLSet : public nsTHashtable<nsURIHashKey> {
  27   NS_INLINE_DECL_REFCOUNTING(VisitedURLSet)
  28
  29  private:
  30   ~VisitedURLSet() = default;
  31 };
  32
  33 // A load request for a module, created for every top level module script and
  34 // every module import.  Load request can share an ModuleScript if there are
  35 // multiple imports of the same module.
  36
  37 class ModuleLoadRequest final : public ScriptLoadRequest {
  38   ~ModuleLoadRequest() {
  39     MOZ_ASSERT(!mWaitingParentRequest);
  40     MOZ_ASSERT(mAwaitingImports == 0);
  41   }
  42
  43   ModuleLoadRequest(const ModuleLoadRequest& aOther) = delete;
  44   ModuleLoadRequest(ModuleLoadRequest&& aOther) = delete;
  45
  46  public:
  47   NS_DECL_ISUPPORTS_INHERITED
  48   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_INHERITED(ModuleLoadRequest,
  49                                                          ScriptLoadRequest)
  50   using SRIMetadata = mozilla::dom::SRIMetadata;
  51
  52   ModuleLoadRequest(nsIURI* aURI, ScriptFetchOptions* aFetchOptions,
  53                     const SRIMetadata& aIntegrity, nsIURI* aReferrer,
  54                     LoadContextBase* aContext, bool aIsTopLevel,
  55                     bool aIsDynamicImport, ModuleLoaderBase* aLoader,
  56                     VisitedURLSet* aVisitedSet, ModuleLoadRequest* aRootModule);
  57
  58   static VisitedURLSet* NewVisitedSetForTopLevelImport(nsIURI* aURI);
  59
  60   bool IsTopLevel() const override { return mIsTopLevel; }
  61
  62   bool IsDynamicImport() const { return mIsDynamicImport; }
  63
  64   bool IsErrored() const;
  65
  66   nsIGlobalObject* GetGlobalObject();
  67
  68   void SetReady() override;
  69   void Cancel() override;
  70   void ClearDynamicImport();
  71
  72   void ModuleLoaded();
  73   void ModuleErrored();
  74   void DependenciesLoaded();
  75   void LoadFailed();
  76
  77   ModuleLoadRequest* GetRootModule() {
  78     if (!mRootModule) {
  79       return this;
  80     }
  81     return mRootModule;
  82   }
  83
  84   bool IsModuleMarkedForBytecodeEncoding() const {
  85     return mIsMarkedForBytecodeEncoding;
  86   }
  87   void MarkModuleForBytecodeEncoding() {
  88     MOZ_ASSERT(!IsModuleMarkedForBytecodeEncoding());
  89     mIsMarkedForBytecodeEncoding = true;
  90   }
  91
  92   // Convenience methods to call into the module loader for this request.
  93
  94   void CancelDynamicImport(nsresult aResult) {
  95     MOZ_ASSERT(IsDynamicImport());
  96     mLoader->CancelDynamicImport(this, aResult);
  97   }
  98 #ifdef DEBUG
  99   bool IsRegisteredDynamicImport() const {
 100     return IsDynamicImport() && mLoader->HasDynamicImport(this);
 101   }
 102 #endif
 103   nsresult StartModuleLoad() { return mLoader->StartModuleLoad(this); }
 104   nsresult RestartModuleLoad() { return mLoader->RestartModuleLoad(this); }
 105   nsresult OnFetchComplete(nsresult aRv) {
 106     return mLoader->OnFetchComplete(this, aRv);
 107   }
 108   bool InstantiateModuleGraph() {
 109     return mLoader->InstantiateModuleGraph(this);
 110   }
 111   nsresult EvaluateModule() { return mLoader->EvaluateModule(this); }
 112   void StartDynamicImport() { mLoader->StartDynamicImport(this); }
 113   void ProcessDynamicImport() { mLoader->ProcessDynamicImport(this); }
 114
 115   void ChildLoadComplete(bool aSuccess);
 116
 117  private:
 118   void LoadFinished();
 119   void CancelImports();
 120   void CheckModuleDependenciesLoaded();
 121
 122   void AssertAllImportsFinished() const;
 123   void AssertAllImportsCancelled() const;
 124
 125  public:
 126   // Is this a request for a top level module script or an import?
 127   const bool mIsTopLevel;
 128
 129   // Is this the top level request for a dynamic module import?
 130   const bool mIsDynamicImport;
 131
 132   // True if this module is planned to be saved in the bytecode cache.
 133   // ModuleLoadRequest doesn't use ScriptLoadRequest::mScriptForBytecodeEncoding
 134   // field because the JSScript reference isn't always avaialble for module.
 135   bool mIsMarkedForBytecodeEncoding = false;
 136
 137   // Pointer to the script loader, used to trigger actions when the module load
 138   // finishes.
 139   RefPtr<ModuleLoaderBase> mLoader;
 140
 141   // Pointer to the top level module of this module graph, nullptr if this is a
 142   // top level module
 143   RefPtr<ModuleLoadRequest> mRootModule;
 144
 145   // Set to a module script object after a successful load or nullptr on
 146   // failure.
 147   RefPtr<ModuleScript> mModuleScript;
 148
 149   // Array of imported modules.
 150   nsTArray<RefPtr<ModuleLoadRequest>> mImports;
 151
 152   // Parent module (i.e. importer of this module) that is waiting for this
 153   // module and its dependencies to load, or null.
 154   RefPtr<ModuleLoadRequest> mWaitingParentRequest;
 155
 156   // Number of child modules (i.e. imported modules) that this module is waiting
 157   // for.
 158   size_t mAwaitingImports = 0;
 159
 160   // Set of module URLs visited while fetching the module graph this request is
 161   // part of.
 162   RefPtr<VisitedURLSet> mVisitedSet;
 163
 164   // For dynamic imports, the details to pass to FinishDynamicImport.
 165   JS::Heap<JS::Value> mDynamicReferencingPrivate;
 166   JS::Heap<JSString*> mDynamicSpecifier;
 167   JS::Heap<JSObject*> mDynamicPromise;
 168 };
 169
 170 }  // namespace JS::loader
 171
 172 #endif  // js_loader_ModuleLoadRequest_h