From 6a1da274be2c9b2e7d8d3a63a181cd882a016a75 Mon Sep 17 00:00:00 2001
From: alwu <alwu@mozilla.com>
Date: Thu, 4 Jan 2024 04:13:05 +0000
Subject: [PATCH] Bug 1825142 - part9 : fix string leaking in testing.
 r=media-playback-reviewers,aosmond

Differential Revision: https://phabricator.services.mozilla.com/D197404
---
 dom/media/eme/mediafoundation/WMFCDMImpl.cpp | 42 +++++++++++++++++---
 1 file changed, 36 insertions(+), 6 deletions(-)

diff --git a/dom/media/eme/mediafoundation/WMFCDMImpl.cpp b/dom/media/eme/mediafoundation/WMFCDMImpl.cpp
index 496960e9fe6a5..1fe42aa8e279f 100644
--- a/dom/media/eme/mediafoundation/WMFCDMImpl.cpp
+++ b/dom/media/eme/mediafoundation/WMFCDMImpl.cpp
@@ -8,6 +8,8 @@
 
 #include <unordered_map>
 
+#include "mozilla/AppShutdown.h"
+#include "mozilla/ClearOnShutdown.h"
 #include "mozilla/dom/MediaKeySession.h"
 #include "mozilla/dom/KeySystemNames.h"
 
@@ -15,27 +17,53 @@ namespace mozilla {
 
 /* static */
 bool WMFCDMImpl::Supports(const nsAString& aKeySystem) {
-  static std::map<nsString, bool> supports;
+  MOZ_ASSERT(NS_IsMainThread());
+  if (AppShutdown::IsInOrBeyond(ShutdownPhase::AppShutdownConfirmed)) {
+    return false;
+  }
+
+  static std::map<nsString, bool> sSupports;
+  static bool sSetRunOnShutdown = false;
+  if (!sSetRunOnShutdown) {
+    GetMainThreadSerialEventTarget()->Dispatch(
+        NS_NewRunnableFunction("WMFCDMImpl::Supports", [&] {
+          RunOnShutdown([&] { sSupports.clear(); },
+                        ShutdownPhase::XPCOMShutdown);
+        }));
+    sSetRunOnShutdown = true;
+  }
 
   nsString key(aKeySystem);
-  if (const auto& s = supports.find(key); s != supports.end()) {
+  if (const auto& s = sSupports.find(key); s != sSupports.end()) {
     return s->second;
   }
 
   RefPtr<WMFCDMImpl> cdm = MakeRefPtr<WMFCDMImpl>(aKeySystem);
   nsTArray<KeySystemConfig> configs;
   bool s = cdm->GetCapabilities(configs);
-  supports[key] = s;
+  sSupports[key] = s;
   return s;
 }
 
 bool WMFCDMImpl::GetCapabilities(nsTArray<KeySystemConfig>& aOutConfigs) {
-  nsCOMPtr<nsISerialEventTarget> backgroundTaskQueue;
-  NS_CreateBackgroundTaskQueue(__func__, getter_AddRefs(backgroundTaskQueue));
+  MOZ_ASSERT(NS_IsMainThread());
+  if (AppShutdown::IsInOrBeyond(ShutdownPhase::AppShutdownConfirmed)) {
+    return false;
+  }
 
-  // Retrieve result from our cached key system
   static std::unordered_map<std::string, nsTArray<KeySystemConfig>>
       sKeySystemConfigs{};
+  static bool sSetRunOnShutdown = false;
+  if (!sSetRunOnShutdown) {
+    GetMainThreadSerialEventTarget()->Dispatch(
+        NS_NewRunnableFunction("WMFCDMImpl::GetCapabilities", [&] {
+          RunOnShutdown([&] { sKeySystemConfigs.clear(); },
+                        ShutdownPhase::XPCOMShutdown);
+        }));
+    sSetRunOnShutdown = true;
+  }
+
+  // Retrieve result from our cached key system
   auto keySystem = std::string{NS_ConvertUTF16toUTF8(mKeySystem).get()};
   if (auto rv = sKeySystemConfigs.find(keySystem);
       rv != sKeySystemConfigs.end()) {
@@ -49,6 +77,8 @@ bool WMFCDMImpl::GetCapabilities(nsTArray<KeySystemConfig>& aOutConfigs) {
   }
 
   // Not cached result, ask the remote process.
+  nsCOMPtr<nsISerialEventTarget> backgroundTaskQueue;
+  NS_CreateBackgroundTaskQueue(__func__, getter_AddRefs(backgroundTaskQueue));
   if (!mCDM) {
     mCDM = MakeRefPtr<MFCDMChild>(mKeySystem);
   }