Bug 1725942 - Part 4: Add StrongWorkerRef r=smaug

Differential Revision: https://phabricator.services.mozilla.com/D127514

Author: saschanaz

dom/locks/LockManager.cpp

@@ -5,6 +5,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "mozilla/dom/LockManager.h"
+#include "mozilla/dom/WorkerCommon.h"
 #include "mozilla/dom/locks/LockManagerChild.h"
 #include "mozilla/dom/locks/LockRequestChild.h"
 #include "mozilla/Assertions.h"
@@ -51,6 +52,18 @@ LockManager::LockManager(nsIGlobalObject* aGlobal) : mOwner(aGlobal) {
   mActor = new locks::LockManagerChild(aGlobal);
   backgroundActor->SendPLockManagerConstructor(mActor, principalInfo,
                                                clientInfo->Id());
+
+  if (!NS_IsMainThread()) {
+    mWorkerRef = WeakWorkerRef::Create(GetCurrentThreadWorkerPrivate(),
+                                       [self = RefPtr(this)]() {
+                                         // Others may grab a strong reference
+                                         // and block immediate destruction.
+                                         // Shutdown early as we don't have to
+                                         // wait for them.
+                                         self->Shutdown();
+                                         self->mWorkerRef = nullptr;
+                                       });
+  }
 }
 
 static bool ValidateRequestArguments(const nsAString& name,

dom/locks/LockManager.h

@@ -13,6 +13,7 @@
 #include "mozilla/dom/BindingDeclarations.h"
 #include "mozilla/dom/Lock.h"
 #include "mozilla/dom/LockManagerBinding.h"
+#include "mozilla/dom/WorkerRef.h"
 #include "nsCycleCollectionParticipant.h"
 #include "nsHashKeys.h"
 #include "nsTHashMap.h"
@@ -59,6 +60,8 @@ class LockManager final : public nsISupports, public nsWrapperCache {
 
   nsCOMPtr<nsIGlobalObject> mOwner;
   RefPtr<locks::LockManagerChild> mActor;
+
+  RefPtr<WeakWorkerRef> mWorkerRef;
 };
 
 }  // namespace mozilla::dom

dom/locks/LockRequestChild.cpp

@@ -8,6 +8,7 @@
 #include "LockRequestChild.h"
 
 #include "mozilla/dom/Promise.h"
+#include "mozilla/dom/WorkerPrivate.h"
 
 namespace mozilla::dom::locks {
 
@@ -36,6 +37,15 @@ MOZ_CAN_RUN_SCRIPT_BOUNDARY static void RunCallbackAndSettlePromise(
   MOZ_ASSERT(!rv.Failed());
 }
 
+LockRequestChild::LockRequestChild(const LockRequest& aRequest)
+    : mRequest(aRequest) {
+  if (!NS_IsMainThread()) {
+    mWorkerRef = StrongWorkerRef::Create(
+        GetCurrentThreadWorkerPrivate(), "LockManager",
+        [self = RefPtr(this)]() { self->mWorkerRef = nullptr; });
+  }
+}
+
 IPCResult LockRequestChild::RecvResolve(const LockMode& aLockMode,
                                         bool aIsAvailable) {
   RefPtr<Lock> lock;

dom/locks/LockRequestChild.h

@@ -9,6 +9,7 @@
 
 #include "mozilla/dom/locks/PLockRequestChild.h"
 #include "mozilla/dom/Lock.h"
+#include "mozilla/dom/WorkerRef.h"
 
 namespace mozilla::dom::locks {
 
@@ -25,7 +26,7 @@ class LockRequestChild final : public PLockRequestChild,
   NS_INLINE_DECL_REFCOUNTING(LockRequestChild)
 
  public:
-  explicit LockRequestChild(const LockRequest& aRequest) : mRequest(aRequest){};
+  explicit LockRequestChild(const LockRequest& aRequest);
 
   IPCResult RecvResolve(const LockMode& aLockMode, bool aIsAvailable);
   IPCResult RecvAbort();
@@ -34,6 +35,7 @@ class LockRequestChild final : public PLockRequestChild,
   ~LockRequestChild() = default;
 
   LockRequest mRequest;
+  RefPtr<StrongWorkerRef> mWorkerRef;
 };
 
 }  // namespace mozilla::dom::locks

dom/locks/moz.build

@@ -7,6 +7,8 @@
 with Files("**"):
     BUG_COMPONENT = ("Core", "DOM: Core & HTML")
 
+MOCHITEST_MANIFESTS += ["test/mochitest.ini"]
+
 EXPORTS.mozilla.dom += [
     "Lock.h",
     "LockManager.h",

dom/locks/test/.eslintrc.js

@@ -0,0 +1,5 @@
+"use strict";
+
+module.exports = {
+  extends: ["plugin:mozilla/mochitest-test"],
+};

dom/locks/test/file_strongworker.js

@@ -0,0 +1,5 @@
+navigator.locks.request("exclusive", () => {
+  const channel = new BroadcastChannel("strongworker");
+  channel.postMessage("lock acquired");
+});
+postMessage("onload");

dom/locks/test/mochitest.ini

@@ -0,0 +1,8 @@
+[DEFAULT]
+scheme = https
+prefs =
+  dom.weblocks.enabled=true
+
+[test_strongworker.html]
+support-files =
+  file_strongworker.js

dom/locks/test/test_strongworker.html

@@ -0,0 +1,30 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<script src="/tests/SimpleTest/SimpleTest.js"></script>
+<link rel="stylesheet" href="/tests/SimpleTest/test.css"/>
+
+<script>
+  SimpleTest.waitForExplicitFinish();
+
+  async function run() {
+    const channel = new BroadcastChannel("strongworker");
+    await navigator.locks.request("exclusive", async () => {
+      await new Promise(resolve => {
+        let worker = new Worker("./file_strongworker.js");
+        worker.onmessage = resolve; // onload
+      });
+      const query = await navigator.locks.query();
+      is(query.pending.length, 1, "Pending request exists");
+
+      // Garbage collect the worker
+      SpecialPowers.DOMWindowUtils.garbageCollect();
+    });
+
+    channel.onmessage = async event => {
+      const query = await navigator.locks.query();
+      is(query.pending.length, 0, "No pending request");
+      SimpleTest.finish();
+    };
+  }
+  run();
+</script>