tor-browser

commit d9af9be984bddd7956a6be5f5256869ca4375efe
parent c06884446e582d0a125cf5635bf03412c59060b9
Author: Daniel Minor <dminor@mozilla.com>
Date:   Fri, 12 Dec 2025 14:12:37 +0000

Bug 1994828 - Set wasm mime type essence for worklets; r=allstarschh

Differential Revision: https://phabricator.services.mozilla.com/D275509

Diffstat:
M
dom/worklet/WorkletFetchHandler.cpp
 | 
53
++++++++++++++++++++++++++++++++++++++++++++++++-----
M
dom/worklet/WorkletFetchHandler.h
 | 
3
+++

2 files changed, 51 insertions(+), 5 deletions(-)
diff --git a/dom/worklet/WorkletFetchHandler.cpp b/dom/worklet/WorkletFetchHandler.cpp
@@ -9,6 +9,7 @@
 #include "js/loader/ModuleLoadRequest.h"
 #include "mozilla/CycleCollectedJSContext.h"
 #include "mozilla/ScopeExit.h"
+#include "mozilla/StaticPrefs_javascript.h"
 #include "mozilla/TaskQueue.h"
 #include "mozilla/dom/Document.h"
 #include "mozilla/dom/Fetch.h"
@@ -161,12 +162,18 @@ class FetchCompleteRunnable final : public Runnable {
  public:
   FetchCompleteRunnable(WorkletImpl* aWorkletImpl, nsIURI* aURI,
                         nsresult aResult,
+#ifdef NIGHTLY_BUILD
+                        bool aHasWasmMimeTypeEssence,
+#endif
                         UniquePtr<uint8_t[]> aScriptBuffer = nullptr,
                         size_t aScriptLength = 0)
       : Runnable("Worklet::FetchCompleteRunnable"),
         mWorkletImpl(aWorkletImpl),
         mURI(aURI),
         mResult(aResult),
+#ifdef NIGHTLY_BUILD
+        mHasWasmMimeTypeEssence(aHasWasmMimeTypeEssence),
+#endif
         mScriptBuffer(std::move(aScriptBuffer)),
         mScriptLength(aScriptLength) {
     MOZ_ASSERT(NS_IsMainThread());
@@ -182,6 +189,9 @@ class FetchCompleteRunnable final : public Runnable {
   RefPtr<WorkletImpl> mWorkletImpl;
   nsCOMPtr<nsIURI> mURI;
   nsresult mResult;
+#ifdef NIGHTLY_BUILD
+  bool mHasWasmMimeTypeEssence;
+#endif
   UniquePtr<uint8_t[]> mScriptBuffer;
   size_t mScriptLength;
 };
@@ -217,6 +227,15 @@ NS_IMETHODIMP FetchCompleteRunnable::RunOnWorkletThread() {
     NS_ENSURE_SUCCESS(rv, rv);
   }
 
+#ifdef NIGHTLY_BUILD
+  // https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-single-module-script
+  // Extract the content-type. If its essence is wasm, we'll attempt to
+  // compile this module as a wasm module. (Steps 13.2, 13.6)
+  if (mHasWasmMimeTypeEssence) {
+    request->SetHasWasmMimeTypeEssence();
+  }
+#endif
+
   request->SetBaseURL(mURI);
   request->OnFetchComplete(mResult);
   moduleLoader->RemoveRequest(mURI);
@@ -499,8 +518,12 @@ nsresult WorkletFetchHandler::StartFetch(JSContext* aCx, nsIURI* aURI,
 }
 
 void WorkletFetchHandler::HandleFetchFailed(nsIURI* aURI) {
-  nsCOMPtr<nsIRunnable> runnable = new FetchCompleteRunnable(
-      mWorklet->mImpl, aURI, NS_ERROR_FAILURE, nullptr, 0);
+  nsCOMPtr<nsIRunnable> runnable =
+      new FetchCompleteRunnable(mWorklet->mImpl, aURI, NS_ERROR_FAILURE,
+#ifdef NIGHTLY_BUILD
+                                false,
+#endif
+                                nullptr, 0);
 
   if (NS_WARN_IF(
           NS_FAILED(mWorklet->mImpl->SendControlMessage(runnable.forget())))) {
@@ -541,6 +564,18 @@ void WorkletScriptHandler::ResolvedCallback(JSContext* aCx,
     return;
   }
 
+#ifdef NIGHTLY_BUILD
+  nsAutoCString contentType;
+  ErrorResult result;
+  if (response->GetInternalHeaders()) {
+    response->GetInternalHeaders()->Get("Content-Type"_ns, contentType, result);
+    if (!result.Failed()) {
+      mHasWasmMimeTypeEssence = nsContentUtils::HasWasmMimeTypeEssence(
+          NS_ConvertUTF8toUTF16(contentType));
+    }
+  }
+#endif
+
   nsCOMPtr<nsIInputStream> inputStream;
   response->GetBody(getter_AddRefs(inputStream));
   if (!inputStream) {
@@ -598,8 +633,12 @@ NS_IMETHODIMP WorkletScriptHandler::OnStreamComplete(nsIStreamLoader* aLoader,
   UniquePtr<uint8_t[]> scriptTextBuf = MakeUnique<uint8_t[]>(aStringLen);
   memcpy(scriptTextBuf.get(), aString, aStringLen);
 
-  nsCOMPtr<nsIRunnable> runnable = new FetchCompleteRunnable(
-      mWorklet->mImpl, mURI, NS_OK, std::move(scriptTextBuf), aStringLen);
+  nsCOMPtr<nsIRunnable> runnable =
+      new FetchCompleteRunnable(mWorklet->mImpl, mURI, NS_OK,
+#ifdef NIGHTLY_BUILD
+                                mHasWasmMimeTypeEssence,
+#endif
+                                std::move(scriptTextBuf), aStringLen);
 
   if (NS_FAILED(mWorklet->mImpl->SendControlMessage(runnable.forget()))) {
     HandleFailure(NS_ERROR_FAILURE);
@@ -625,7 +664,11 @@ void WorkletScriptHandler::HandleFailure(nsresult aResult) {
 
 void WorkletScriptHandler::DispatchFetchCompleteToWorklet(nsresult aRv) {
   nsCOMPtr<nsIRunnable> runnable =
-      new FetchCompleteRunnable(mWorklet->mImpl, mURI, aRv, nullptr, 0);
+      new FetchCompleteRunnable(mWorklet->mImpl, mURI, aRv,
+#ifdef NIGHTLY_BUILD
+                                mHasWasmMimeTypeEssence,
+#endif
+                                nullptr, 0);
 
   if (NS_WARN_IF(
           NS_FAILED(mWorklet->mImpl->SendControlMessage(runnable.forget())))) {
diff --git a/dom/worklet/WorkletFetchHandler.h b/dom/worklet/WorkletFetchHandler.h
@@ -114,6 +114,9 @@ class WorkletScriptHandler final : public PromiseNativeHandler,
 
   RefPtr<Worklet> mWorklet;
   nsCOMPtr<nsIURI> mURI;
+#ifdef NIGHTLY_BUILD
+  bool mHasWasmMimeTypeEssence = false;
+#endif
 };
 
 }  // namespace mozilla::dom