Bug 1102060 - Part1: Add two new functions to get TabParent in ContentProcessManager by given ContentParentId and TabId. r=kanru

dom/ipc/ContentProcessManager.cpp

@@ -6,6 +6,7 @@
 
 #include "ContentProcessManager.h"
 #include "ContentParent.h"
+#include "mozilla/dom/TabParent.h"
 
 #include "mozilla/StaticPtr.h"
 #include "mozilla/ClearOnShutdown.h"
@@ -276,5 +277,62 @@ ContentProcessManager::GetRemoteFrameOpenerTabId(const ContentParentId& aChildCp
   return true;
 }
 
+already_AddRefed<TabParent>
+ContentProcessManager::GetTabParentByProcessAndTabId(const ContentParentId& aChildCpId,
+                                                     const TabId& aChildTabId)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  auto iter = mContentParentMap.find(aChildCpId);
+  if (NS_WARN_IF(iter == mContentParentMap.end())) {
+    ASSERT_UNLESS_FUZZING();
+    return nullptr;
+  }
+
+  const InfallibleTArray<PBrowserParent*>& browsers =
+    iter->second.mCp->ManagedPBrowserParent();
+  for (uint32_t i = 0; i < browsers.Length(); i++) {
+    nsRefPtr<TabParent> tab = static_cast<TabParent*>(browsers[i]);
+    if (tab->GetTabId() == aChildTabId) {
+      return tab.forget();
+    }
+  }
+
+  return nullptr;
+}
+
+already_AddRefed<TabParent>
+ContentProcessManager::GetTopLevelTabParentByProcessAndTabId(const ContentParentId& aChildCpId,
+                                                             const TabId& aChildTabId)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  // Used to keep the current ContentParentId and the current TabId
+  // in the iteration(do-while loop below)
+  ContentParentId currentCpId;
+  TabId currentTabId;
+
+  // To get the ContentParentId and the TabParentId on upper level
+  ContentParentId parentCpId = aChildCpId;
+  TabId openerTabId = aChildTabId;
+
+  // Stop this loop when the upper ContentParentId of
+  // the current ContentParentId is chrome(ContentParentId = 0).
+  do {
+    // Update the current ContentParentId and TabId in iteration
+    currentCpId = parentCpId;
+    currentTabId = openerTabId;
+
+    // Get the ContentParentId and TabId on upper level
+    if (!GetParentProcessId(currentCpId, &parentCpId) ||
+        !GetRemoteFrameOpenerTabId(currentCpId, currentTabId, &openerTabId)) {
+      return nullptr;
+    }
+  } while (parentCpId);
+
+  // Get the top level TabParent by the current ContentParentId and TabId
+  return GetTabParentByProcessAndTabId(currentCpId, currentTabId);
+}
+
 } // namespace dom
 } // namespace mozilla

dom/ipc/ContentProcessManager.h

@@ -110,6 +110,31 @@ public:
                                  const TabId& aChildTabId,
                                  /*out*/ TabId* aOpenerTabId);
 
+  /**
+   * Get the TabParent by the given content process and tab id.
+   * Return nullptr when TabParent couldn't be found via aChildCpId
+   * and aChildTabId.
+   * (or probably because the TabParent is not in the chrome process)
+   */
+  already_AddRefed<TabParent>
+  GetTabParentByProcessAndTabId(const ContentParentId& aChildCpId,
+                                const TabId& aChildTabId);
+
+  /**
+   * Get the TabParent on top level by the given content process and tab id.
+   *
+   *  This function return the TabParent belong to the chrome process,
+   *  called top-level TabParent here, by given aChildCpId and aChildTabId.
+   *  The given aChildCpId and aChildTabId are related to a content process
+   *  and a tab respectively. In nested-oop, the top-level TabParent isn't
+   *  always the opener tab of the given tab in content process. This function
+   *  will call GetTabParentByProcessAndTabId iteratively until the Tab returned
+   *  is belong to the chrome process.
+   */
+  already_AddRefed<TabParent>
+  GetTopLevelTabParentByProcessAndTabId(const ContentParentId& aChildCpId,
+                                        const TabId& aChildTabId);
+
 private:
   static StaticAutoPtr<ContentProcessManager> sSingleton;
   TabId mUniqueId;
@@ -120,4 +145,4 @@ private:
 
 } // namespace dom
 } // namespace mozilla
-#endif
+#endif