dom/script/ScriptLoadContext.cpp

   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 #include "GeckoProfiler.h"
   8
   9 #include "mozilla/dom/Document.h"
  10 #include "mozilla/HoldDropJSObjects.h"
  11 #include "mozilla/StaticPrefs_dom.h"
  12 #include "mozilla/Unused.h"
  13 #include "mozilla/Utf8.h"  // mozilla::Utf8Unit
  14
  15 #include "js/OffThreadScriptCompilation.h"
  16 #include "js/SourceText.h"
  17 #include "js/loader/LoadContextBase.h"
  18 #include "js/loader/ModuleLoadRequest.h"
  19
  20 #include "ScriptLoadContext.h"
  21 #include "ModuleLoadRequest.h"
  22 #include "nsContentUtils.h"
  23 #include "nsICacheInfoChannel.h"
  24 #include "nsIClassOfService.h"
  25 #include "nsISupportsPriority.h"
  26
  27 namespace mozilla::dom {
  28
  29 //////////////////////////////////////////////////////////////
  30 // ScriptLoadContext
  31 //////////////////////////////////////////////////////////////
  32
  33 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ScriptLoadContext)
  34 NS_INTERFACE_MAP_END_INHERITING(JS::loader::LoadContextBase)
  35
  36 NS_IMPL_CYCLE_COLLECTION_CLASS(ScriptLoadContext)
  37
  38 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(ScriptLoadContext,
  39                                                 JS::loader::LoadContextBase)
  40   MOZ_ASSERT(!tmp->mOffThreadToken);
  41   MOZ_ASSERT(!tmp->mRunnable);
  42   tmp->MaybeUnblockOnload();
  43 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
  44
  45 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(ScriptLoadContext,
  46                                                   JS::loader::LoadContextBase)
  47   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mLoadBlockedDocument)
  48 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
  49
  50 NS_IMPL_ADDREF_INHERITED(ScriptLoadContext, JS::loader::LoadContextBase)
  51 NS_IMPL_RELEASE_INHERITED(ScriptLoadContext, JS::loader::LoadContextBase)
  52
  53 ScriptLoadContext::ScriptLoadContext()
  54     : JS::loader::LoadContextBase(JS::loader::ContextKind::Window),
  55       mScriptMode(ScriptMode::eBlocking),
  56       mScriptFromHead(false),
  57       mIsInline(true),
  58       mInDeferList(false),
  59       mInAsyncList(false),
  60       mIsNonAsyncScriptInserted(false),
  61       mIsXSLT(false),
  62       mInCompilingList(false),
  63       mIsTracking(false),
  64       mWasCompiledOMT(false),
  65       mOffThreadToken(nullptr),
  66       mRunnable(nullptr),
  67       mLineNo(1),
  68       mColumnNo(0),
  69       mIsPreload(false),
  70       mUnreportedPreloadError(NS_OK) {}
  71
  72 ScriptLoadContext::~ScriptLoadContext() {
  73   MOZ_ASSERT(NS_IsMainThread());
  74
  75   // Off-thread parsing must have completed by this point.
  76   MOZ_DIAGNOSTIC_ASSERT(!mOffThreadToken && !mRunnable);
  77
  78   mRequest = nullptr;
  79
  80   MaybeUnblockOnload();
  81 }
  82
  83 void ScriptLoadContext::BlockOnload(Document* aDocument) {
  84   MOZ_ASSERT(!mLoadBlockedDocument);
  85   aDocument->BlockOnload();
  86   mLoadBlockedDocument = aDocument;
  87 }
  88
  89 void ScriptLoadContext::MaybeUnblockOnload() {
  90   if (mLoadBlockedDocument) {
  91     mLoadBlockedDocument->UnblockOnload(false);
  92     mLoadBlockedDocument = nullptr;
  93   }
  94 }
  95
  96 void ScriptLoadContext::MaybeCancelOffThreadScript() {
  97   MOZ_ASSERT(NS_IsMainThread());
  98
  99   if (!mOffThreadToken) {
 100     return;
 101   }
 102
 103   // Cancel parse if it hasn't been started yet or wait for it to finish and
 104   // clean up finished parse data.
 105   JSContext* cx = danger::GetJSContext();
 106   JS::CancelOffThreadToken(cx, mOffThreadToken);
 107   mOffThreadToken = nullptr;
 108
 109   // Clear the pointer to the runnable. It may still run later if we didn't
 110   // cancel in time. In this case the runnable is held live by the reference
 111   // passed to Dispatch, which is dropped after it runs.
 112   mRunnable = nullptr;
 113
 114   MaybeUnblockOnload();
 115 }
 116
 117 void ScriptLoadContext::SetScriptMode(bool aDeferAttr, bool aAsyncAttr,
 118                                       bool aLinkPreload) {
 119   if (aLinkPreload) {
 120     mScriptMode = ScriptMode::eLinkPreload;
 121   } else if (aAsyncAttr) {
 122     mScriptMode = ScriptMode::eAsync;
 123   } else if (aDeferAttr || mRequest->IsModuleRequest()) {
 124     mScriptMode = ScriptMode::eDeferred;
 125   } else {
 126     mScriptMode = ScriptMode::eBlocking;
 127   }
 128 }
 129
 130 // static
 131 void ScriptLoadContext::PrioritizeAsPreload(nsIChannel* aChannel) {
 132   if (nsCOMPtr<nsIClassOfService> cos = do_QueryInterface(aChannel)) {
 133     cos->AddClassFlags(nsIClassOfService::Unblocked);
 134   }
 135   if (nsCOMPtr<nsISupportsPriority> sp = do_QueryInterface(aChannel)) {
 136     sp->AdjustPriority(nsISupportsPriority::PRIORITY_HIGHEST);
 137   }
 138 }
 139
 140 void ScriptLoadContext::PrioritizeAsPreload() {
 141   if (!IsLinkPreloadScript()) {
 142     // Do the prioritization only if this request has not already been created
 143     // as a preload.
 144     PrioritizeAsPreload(Channel());
 145   }
 146 }
 147
 148 bool ScriptLoadContext::IsPreload() const {
 149   if (mRequest->IsModuleRequest() && !mRequest->IsTopLevel()) {
 150     JS::loader::ModuleLoadRequest* root =
 151         mRequest->AsModuleRequest()->GetRootModule();
 152     return root->GetScriptLoadContext()->IsPreload();
 153   }
 154
 155   MOZ_ASSERT_IF(mIsPreload, !GetScriptElement());
 156   return mIsPreload;
 157 }
 158
 159 bool ScriptLoadContext::CompileStarted() const {
 160   return mRequest->IsCompiling() || (mRequest->IsFinished() && mWasCompiledOMT);
 161 }
 162
 163 nsIScriptElement* ScriptLoadContext::GetScriptElement() const {
 164   nsCOMPtr<nsIScriptElement> scriptElement =
 165       do_QueryInterface(mRequest->mFetchOptions->mElement);
 166   return scriptElement;
 167 }
 168
 169 void ScriptLoadContext::SetIsLoadRequest(nsIScriptElement* aElement) {
 170   MOZ_ASSERT(aElement);
 171   MOZ_ASSERT(!GetScriptElement());
 172   MOZ_ASSERT(IsPreload());
 173   // We are not tracking our own element, and are relying on the one in
 174   // FetchOptions.
 175   mRequest->mFetchOptions->mElement = do_QueryInterface(aElement);
 176   mIsPreload = false;
 177 }
 178
 179 void ScriptLoadContext::GetProfilerLabel(nsACString& aOutString) {
 180   if (!profiler_is_active()) {
 181     aOutString.Append("<script> element");
 182     return;
 183   }
 184   aOutString.Append("<script");
 185   if (IsAsyncScript()) {
 186     aOutString.Append(" async");
 187   } else if (IsDeferredScript()) {
 188     aOutString.Append(" defer");
 189   }
 190   if (mRequest->IsModuleRequest()) {
 191     aOutString.Append(" type=\"module\"");
 192   }
 193
 194   nsAutoCString url;
 195   if (mRequest->mURI) {
 196     mRequest->mURI->GetAsciiSpec(url);
 197   } else {
 198     url = "<unknown>";
 199   }
 200
 201   if (mIsInline) {
 202     if (GetParserCreated() != NOT_FROM_PARSER) {
 203       aOutString.Append("> inline at line ");
 204       aOutString.AppendInt(mLineNo);
 205       aOutString.Append(" of ");
 206     } else {
 207       aOutString.Append("> inline (dynamically created) in ");
 208     }
 209     aOutString.Append(url);
 210   } else {
 211     aOutString.Append(" src=\"");
 212     aOutString.Append(url);
 213     aOutString.Append("\">");
 214   }
 215 }
 216
 217 }  // namespace mozilla::dom