Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 493 insertions, 0 deletions

diff --git a/dom/base/nsCCUncollectableMarker.cpp b/dom/base/nsCCUncollectableMarker.cpp
new file mode 100644
index 0000000000..79291f727f
--- /dev/null
+++ b/dom/base/nsCCUncollectableMarker.cpp
@@ -0,0 +1,493 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsCCUncollectableMarker.h"
+#include "nsIObserverService.h"
+#include "nsIDocShell.h"
+#include "nsServiceManagerUtils.h"
+#include "nsIContentViewer.h"
+#include "mozilla/dom/Document.h"
+#include "InProcessBrowserChildMessageManager.h"
+#include "nsIWindowMediator.h"
+#include "nsPIDOMWindow.h"
+#include "nsIWebNavigation.h"
+#include "nsISHistory.h"
+#include "nsISHEntry.h"
+#include "nsIWindowWatcher.h"
+#include "mozilla/Services.h"
+#include "nsIAppWindow.h"
+#include "nsIAppShellService.h"
+#include "nsAppShellCID.h"
+#include "nsContentUtils.h"
+#include "nsGlobalWindow.h"
+#include "nsJSEnvironment.h"
+#include "nsFrameLoader.h"
+#include "mozilla/CycleCollectedJSContext.h"
+#include "mozilla/CycleCollectedJSRuntime.h"
+#include "mozilla/EventListenerManager.h"
+#include "mozilla/dom/ChromeMessageBroadcaster.h"
+#include "mozilla/dom/ContentFrameMessageManager.h"
+#include "mozilla/dom/ContentProcessMessageManager.h"
+#include "mozilla/dom/CustomElementRegistry.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/ParentProcessMessageManager.h"
+#include "mozilla/dom/BrowserChild.h"
+#include "mozilla/dom/TimeoutManager.h"
+#include "xpcpublic.h"
+#include "nsObserverService.h"
+#include "nsFocusManager.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsIXULRuntime.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+static bool sInited = 0;
+// The initial value of sGeneration should not be the same as the
+// value it is given at xpcom-shutdown, because this will make any GCs
+// before we first CC benignly violate the black-gray invariant, due
+// to dom::TraceBlackJS().
+uint32_t nsCCUncollectableMarker::sGeneration = 1;
+#include "nsXULPrototypeCache.h"
+
+NS_IMPL_ISUPPORTS(nsCCUncollectableMarker, nsIObserver)
+
+/* static */
+nsresult nsCCUncollectableMarker::Init() {
+  if (sInited) {
+    return NS_OK;
+  }
+
+  nsCOMPtr<nsIObserver> marker = new nsCCUncollectableMarker;
+
+  nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
+  if (!obs) return NS_ERROR_FAILURE;
+
+  nsresult rv;
+
+  // This makes the observer service hold an owning reference to the marker
+  rv = obs->AddObserver(marker, "xpcom-shutdown", false);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = obs->AddObserver(marker, "cycle-collector-begin", false);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = obs->AddObserver(marker, "cycle-collector-forget-skippable", false);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  sInited = true;
+
+  return NS_OK;
+}
+
+static void MarkChildMessageManagers(MessageBroadcaster* aMM) {
+  aMM->MarkForCC();
+
+  uint32_t browserChildCount = aMM->ChildCount();
+  for (uint32_t j = 0; j < browserChildCount; ++j) {
+    RefPtr<MessageListenerManager> childMM = aMM->GetChildAt(j);
+    if (!childMM) {
+      continue;
+    }
+
+    RefPtr<MessageBroadcaster> strongNonLeafMM =
+        MessageBroadcaster::From(childMM);
+    MessageBroadcaster* nonLeafMM = strongNonLeafMM;
+
+    MessageListenerManager* tabMM = childMM;
+
+    strongNonLeafMM = nullptr;
+    childMM = nullptr;
+
+    if (nonLeafMM) {
+      MarkChildMessageManagers(nonLeafMM);
+      continue;
+    }
+
+    tabMM->MarkForCC();
+
+    // XXX hack warning, but works, since we know that
+    //    callback is frameloader.
+    mozilla::dom::ipc::MessageManagerCallback* cb = tabMM->GetCallback();
+    if (cb) {
+      nsFrameLoader* fl = static_cast<nsFrameLoader*>(cb);
+      InProcessBrowserChildMessageManager* et =
+          fl->GetBrowserChildMessageManager();
+      if (!et) {
+        continue;
+      }
+      et->MarkForCC();
+      EventListenerManager* elm = et->GetExistingListenerManager();
+      if (elm) {
+        elm->MarkForCC();
+      }
+    }
+  }
+}
+
+static void MarkMessageManagers() {
+  if (nsFrameMessageManager::GetChildProcessManager()) {
+    // ContentProcessMessageManager's MarkForCC also marks ChildProcessManager.
+    ContentProcessMessageManager* pg = ContentProcessMessageManager::Get();
+    if (pg) {
+      pg->MarkForCC();
+    }
+  }
+
+  // The global message manager only exists in the root process.
+  if (!XRE_IsParentProcess()) {
+    return;
+  }
+  RefPtr<ChromeMessageBroadcaster> strongGlobalMM =
+      nsFrameMessageManager::GetGlobalMessageManager();
+  if (!strongGlobalMM) {
+    return;
+  }
+  ChromeMessageBroadcaster* globalMM = strongGlobalMM;
+  strongGlobalMM = nullptr;
+  MarkChildMessageManagers(globalMM);
+
+  if (nsFrameMessageManager::sParentProcessManager) {
+    nsFrameMessageManager::sParentProcessManager->MarkForCC();
+    uint32_t childCount =
+        nsFrameMessageManager::sParentProcessManager->ChildCount();
+    for (uint32_t i = 0; i < childCount; ++i) {
+      RefPtr<MessageListenerManager> childMM =
+          nsFrameMessageManager::sParentProcessManager->GetChildAt(i);
+      if (!childMM) {
+        continue;
+      }
+      MessageListenerManager* child = childMM;
+      childMM = nullptr;
+      child->MarkForCC();
+    }
+  }
+  if (nsFrameMessageManager::sSameProcessParentManager) {
+    nsFrameMessageManager::sSameProcessParentManager->MarkForCC();
+  }
+}
+
+void MarkContentViewer(nsIContentViewer* aViewer, bool aCleanupJS) {
+  if (!aViewer) {
+    return;
+  }
+
+  Document* doc = aViewer->GetDocument();
+  if (doc &&
+      doc->GetMarkedCCGeneration() != nsCCUncollectableMarker::sGeneration) {
+    doc->MarkUncollectableForCCGeneration(nsCCUncollectableMarker::sGeneration);
+    if (aCleanupJS) {
+      EventListenerManager* elm = doc->GetExistingListenerManager();
+      if (elm) {
+        elm->MarkForCC();
+      }
+      RefPtr<nsGlobalWindowInner> win =
+          nsGlobalWindowInner::Cast(doc->GetInnerWindow());
+      if (win) {
+        elm = win->GetExistingListenerManager();
+        if (elm) {
+          elm->MarkForCC();
+        }
+        win->TimeoutManager().UnmarkGrayTimers();
+      }
+    }
+  }
+  if (doc) {
+    if (nsPIDOMWindowInner* inner = doc->GetInnerWindow()) {
+      inner->MarkUncollectableForCCGeneration(
+          nsCCUncollectableMarker::sGeneration);
+    }
+    if (nsPIDOMWindowOuter* outer = doc->GetWindow()) {
+      outer->MarkUncollectableForCCGeneration(
+          nsCCUncollectableMarker::sGeneration);
+    }
+  }
+}
+
+void MarkDocShell(nsIDocShellTreeItem* aNode, bool aCleanupJS);
+
+void MarkSHEntry(nsISHEntry* aSHEntry, bool aCleanupJS) {
+  if (!aSHEntry) {
+    return;
+  }
+
+  nsCOMPtr<nsIContentViewer> cview;
+  aSHEntry->GetContentViewer(getter_AddRefs(cview));
+  MarkContentViewer(cview, aCleanupJS);
+
+  nsCOMPtr<nsIDocShellTreeItem> child;
+  int32_t i = 0;
+  while (NS_SUCCEEDED(aSHEntry->ChildShellAt(i++, getter_AddRefs(child))) &&
+         child) {
+    MarkDocShell(child, aCleanupJS);
+  }
+
+  int32_t count;
+  aSHEntry->GetChildCount(&count);
+  for (i = 0; i < count; ++i) {
+    nsCOMPtr<nsISHEntry> childEntry;
+    aSHEntry->GetChildAt(i, getter_AddRefs(childEntry));
+    MarkSHEntry(childEntry, aCleanupJS);
+  }
+}
+
+void MarkDocShell(nsIDocShellTreeItem* aNode, bool aCleanupJS) {
+  nsCOMPtr<nsIDocShell> shell = do_QueryInterface(aNode);
+  if (!shell) {
+    return;
+  }
+
+  nsCOMPtr<nsIContentViewer> cview;
+  shell->GetContentViewer(getter_AddRefs(cview));
+  MarkContentViewer(cview, aCleanupJS);
+
+  nsCOMPtr<nsIWebNavigation> webNav = do_QueryInterface(shell);
+  RefPtr<ChildSHistory> history = webNav->GetSessionHistory();
+  IgnoredErrorResult ignore;
+  nsISHistory* legacyHistory =
+      history ? history->GetLegacySHistory(ignore) : nullptr;
+  if (legacyHistory) {
+    MOZ_DIAGNOSTIC_ASSERT(!mozilla::SessionHistoryInParent());
+    int32_t historyCount = history->Count();
+    for (int32_t i = 0; i < historyCount; ++i) {
+      nsCOMPtr<nsISHEntry> shEntry;
+      legacyHistory->GetEntryAtIndex(i, getter_AddRefs(shEntry));
+
+      MarkSHEntry(shEntry, aCleanupJS);
+    }
+  }
+
+  int32_t i, childCount;
+  aNode->GetInProcessChildCount(&childCount);
+  for (i = 0; i < childCount; ++i) {
+    nsCOMPtr<nsIDocShellTreeItem> child;
+    aNode->GetInProcessChildAt(i, getter_AddRefs(child));
+    MarkDocShell(child, aCleanupJS);
+  }
+}
+
+void MarkWindowList(nsISimpleEnumerator* aWindowList, bool aCleanupJS) {
+  nsCOMPtr<nsISupports> iter;
+  while (NS_SUCCEEDED(aWindowList->GetNext(getter_AddRefs(iter))) && iter) {
+    if (nsCOMPtr<nsPIDOMWindowOuter> window = do_QueryInterface(iter)) {
+      nsCOMPtr<nsIDocShell> rootDocShell = window->GetDocShell();
+
+      MarkDocShell(rootDocShell, aCleanupJS);
+
+      RefPtr<BrowserChild> browserChild = BrowserChild::GetFrom(rootDocShell);
+      if (browserChild) {
+        RefPtr<BrowserChildMessageManager> mm =
+            browserChild->GetMessageManager();
+        if (mm) {
+          // MarkForCC ends up calling UnmarkGray on message listeners, which
+          // TraceBlackJS can't do yet.
+          mm->MarkForCC();
+        }
+      }
+    }
+  }
+}
+
+nsresult nsCCUncollectableMarker::Observe(nsISupports* aSubject,
+                                          const char* aTopic,
+                                          const char16_t* aData) {
+  if (!strcmp(aTopic, "xpcom-shutdown")) {
+    Element::ClearContentUnbinder();
+
+    nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
+    if (!obs) return NS_ERROR_FAILURE;
+
+    // No need for kungFuDeathGrip here, yay observerservice!
+    obs->RemoveObserver(this, "xpcom-shutdown");
+    obs->RemoveObserver(this, "cycle-collector-begin");
+    obs->RemoveObserver(this, "cycle-collector-forget-skippable");
+
+    sGeneration = 0;
+
+    return NS_OK;
+  }
+
+  NS_ASSERTION(!strcmp(aTopic, "cycle-collector-begin") ||
+                   !strcmp(aTopic, "cycle-collector-forget-skippable"),
+               "wrong topic");
+
+  // JS cleanup can be slow. Do it only if this is the first forget-skippable
+  // after a GC.
+  const bool cleanupJS = nsJSContext::HasHadCleanupSinceLastGC() &&
+                         !strcmp(aTopic, "cycle-collector-forget-skippable");
+
+  const bool prepareForCC = !strcmp(aTopic, "cycle-collector-begin");
+  if (prepareForCC) {
+    Element::ClearContentUnbinder();
+  }
+
+  // Increase generation to effectively unmark all current objects
+  if (!++sGeneration) {
+    ++sGeneration;
+  }
+
+  nsFocusManager::MarkUncollectableForCCGeneration(sGeneration);
+
+  nsresult rv;
+
+  // Iterate all toplevel windows
+  nsCOMPtr<nsISimpleEnumerator> windowList;
+  nsCOMPtr<nsIWindowMediator> med = do_GetService(NS_WINDOWMEDIATOR_CONTRACTID);
+  if (med) {
+    rv = med->GetEnumerator(nullptr, getter_AddRefs(windowList));
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    MarkWindowList(windowList, cleanupJS);
+  }
+
+  nsCOMPtr<nsIWindowWatcher> ww = do_GetService(NS_WINDOWWATCHER_CONTRACTID);
+  if (ww) {
+    rv = ww->GetWindowEnumerator(getter_AddRefs(windowList));
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    MarkWindowList(windowList, cleanupJS);
+  }
+
+  nsCOMPtr<nsIAppShellService> appShell =
+      do_GetService(NS_APPSHELLSERVICE_CONTRACTID);
+  if (appShell) {
+    bool hasHiddenWindow = false;
+    appShell->GetHasHiddenWindow(&hasHiddenWindow);
+    if (hasHiddenWindow) {
+      nsCOMPtr<nsIAppWindow> hw;
+      appShell->GetHiddenWindow(getter_AddRefs(hw));
+      nsCOMPtr<nsIDocShell> shell;
+      hw->GetDocShell(getter_AddRefs(shell));
+      MarkDocShell(shell, cleanupJS);
+    }
+  }
+
+  nsXULPrototypeCache* xulCache = nsXULPrototypeCache::GetInstance();
+  if (xulCache) {
+    xulCache->MarkInCCGeneration(sGeneration);
+  }
+
+  enum ForgetSkippableCleanupState {
+    eInitial = 0,
+    eUnmarkJSEventListeners = 1,
+    eUnmarkMessageManagers = 2,
+    eUnmarkStrongObservers = 3,
+    eUnmarkJSHolders = 4,
+    eDone = 5
+  };
+
+  static_assert(eDone == kMajorForgetSkippableCalls,
+                "There must be one forgetSkippable call per cleanup state.");
+
+  static uint32_t sFSState = eDone;
+  if (prepareForCC) {
+    sFSState = eDone;
+    return NS_OK;
+  }
+
+  if (cleanupJS) {
+    // After a GC we start clean up phases from the beginning,
+    // but we don't want to do the additional clean up phases here
+    // since we have done already plenty of gray unmarking while going through
+    // frame message managers and docshells.
+    sFSState = eInitial;
+    return NS_OK;
+  } else {
+    ++sFSState;
+  }
+
+  switch (sFSState) {
+    case eUnmarkJSEventListeners: {
+      nsContentUtils::UnmarkGrayJSListenersInCCGenerationDocuments();
+      break;
+    }
+    case eUnmarkMessageManagers: {
+      MarkMessageManagers();
+      break;
+    }
+    case eUnmarkStrongObservers: {
+      nsCOMPtr<nsIObserverService> obs =
+          mozilla::services::GetObserverService();
+      static_cast<nsObserverService*>(obs.get())->UnmarkGrayStrongObservers();
+      break;
+    }
+    case eUnmarkJSHolders: {
+      xpc_UnmarkSkippableJSHolders();
+      break;
+    }
+    default: {
+      break;
+    }
+  }
+
+  return NS_OK;
+}
+
+void mozilla::dom::TraceBlackJS(JSTracer* aTrc) {
+  if (!nsCCUncollectableMarker::sGeneration) {
+    return;
+  }
+
+  if (ContentProcessMessageManager::WasCreated() &&
+      nsFrameMessageManager::GetChildProcessManager()) {
+    auto* pg = ContentProcessMessageManager::Get();
+    if (pg) {
+      mozilla::TraceScriptHolder(ToSupports(pg), aTrc);
+    }
+  }
+
+  // Mark globals of active windows black.
+  nsGlobalWindowOuter::OuterWindowByIdTable* windowsById =
+      nsGlobalWindowOuter::GetWindowsTable();
+  if (windowsById) {
+    for (nsGlobalWindowOuter* window : windowsById->Values()) {
+      if (!window->IsCleanedUp()) {
+        nsGlobalWindowInner* inner = nullptr;
+        for (PRCList* win = PR_LIST_HEAD(window); win != window;
+             win = PR_NEXT_LINK(inner)) {
+          inner = static_cast<nsGlobalWindowInner*>(win);
+          if (inner->IsCurrentInnerWindow() ||
+              (inner->GetExtantDoc() &&
+               inner->GetExtantDoc()->GetBFCacheEntry())) {
+            inner->TraceGlobalJSObject(aTrc);
+            EventListenerManager* elm = inner->GetExistingListenerManager();
+            if (elm) {
+              elm->TraceListeners(aTrc);
+            }
+            CustomElementRegistry* cer = inner->GetExistingCustomElements();
+            if (cer) {
+              cer->TraceDefinitions(aTrc);
+            }
+          }
+        }
+
+        if (window->IsRootOuterWindow()) {
+          // In child process trace all the BrowserChildMessageManagers.
+          // Since there is one root outer window per
+          // BrowserChildMessageManager, we need to look for only those windows,
+          // not all.
+          nsIDocShell* ds = window->GetDocShell();
+          if (ds) {
+            nsCOMPtr<nsIBrowserChild> browserChild = ds->GetBrowserChild();
+            if (browserChild) {
+              RefPtr<ContentFrameMessageManager> mm;
+              browserChild->GetMessageManager(getter_AddRefs(mm));
+              if (mm) {
+                nsCOMPtr<nsISupports> browserChildAsSupports =
+                    do_QueryInterface(browserChild);
+                mozilla::TraceScriptHolder(browserChildAsSupports, aTrc);
+                EventListenerManager* elm = mm->GetExistingListenerManager();
+                if (elm) {
+                  elm->TraceListeners(aTrc);
+                }
+                // As of now there isn't an easy way to trace message listeners.
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}