Bug 1617132 - Make FileInfo non-polymorphic and merge with its templated subclass. r=dom-workers-and-storage-reviewers,janv

Differential Revision: https://phabricator.services.mozilla.com/D63627

--HG--
extra : moz-landing-system : lando

dom/indexedDB/ActorsParent.cpp

@@ -16109,18 +16109,17 @@ nsresult FileManager::Init(nsIFile* aDirectory,
       return rv;
     }
 
-    int32_t refcount;
-    rv = stmt->GetInt32(1, &refcount);
+    int32_t dbRefCnt;
+    rv = stmt->GetInt32(1, &dbRefCnt);
     if (NS_WARN_IF(NS_FAILED(rv))) {
       return rv;
     }
 
-    MOZ_ASSERT(refcount > 0);
-
-    RefPtr<FileInfo> fileInfo = FileInfo::Create(this, id);
-    fileInfo->mDBRefCnt = static_cast<nsrefcnt>(refcount);
-
-    mFileInfos.Put(id, fileInfo);
+    // We put a raw pointer into the hash table, so the memory refcount will be
+    // 0, but the dbRefCnt is non-zero, which will keep the FileInfo object
+    // alive.
+    MOZ_ASSERT(dbRefCnt > 0);
+    mFileInfos.Put(id, new FileInfo(this, id, static_cast<nsrefcnt>(dbRefCnt)));
 
     mLastFileId = std::max(id, mLastFileId);
   }
@@ -16245,7 +16244,7 @@ RefPtr<FileInfo> FileManager::GetNewFileInfo() {
 
     int64_t id = mLastFileId + 1;
 
-    fileInfo = FileInfo::Create(this, id);
+    fileInfo = new FileInfo(this, id);
 
     mFileInfos.Put(id, fileInfo);
 

dom/indexedDB/FileInfo.cpp

@@ -24,47 +24,6 @@ namespace indexedDB {
 using namespace mozilla::dom::quota;
 using namespace mozilla::ipc;
 
-namespace {
-
-template <typename IdType>
-class FileInfoImpl final : public FileInfo {
-  IdType mFileId;
-
- public:
-  FileInfoImpl(FileManager* aFileManager, IdType aFileId)
-      : FileInfo(aFileManager), mFileId(aFileId) {
-    MOZ_ASSERT(aFileManager);
-    MOZ_ASSERT(aFileId > 0);
-  }
-
- private:
-  ~FileInfoImpl() = default;
-
-  virtual int64_t Id() const override { return int64_t(mFileId); }
-};
-
-}  // namespace
-
-FileInfo::FileInfo(FileManager* aFileManager) : mFileManager(aFileManager) {
-  MOZ_ASSERT(aFileManager);
-}
-
-// static
-FileInfo* FileInfo::Create(FileManager* aFileManager, int64_t aId) {
-  MOZ_ASSERT(aFileManager);
-  MOZ_ASSERT(aId > 0);
-
-  if (aId <= INT16_MAX) {
-    return new FileInfoImpl<int16_t>(aFileManager, aId);
-  }
-
-  if (aId <= INT32_MAX) {
-    return new FileInfoImpl<int32_t>(aFileManager, aId);
-  }
-
-  return new FileInfoImpl<int64_t>(aFileManager, aId);
-}
-
 void FileInfo::GetReferences(int32_t* aRefCnt, int32_t* aDBRefCnt,
                              int32_t* aSliceRefCnt) {
   MOZ_ASSERT(!IndexedDatabaseManager::IsClosed());

dom/indexedDB/FileInfo.h

@@ -15,21 +15,28 @@ namespace indexedDB {
 
 class FileManager;
 
-class FileInfo {
+class FileInfo final {
   friend class FileManager;
 
+  const int64_t mFileId;
+
   ThreadSafeAutoRefCnt mRefCnt;
   ThreadSafeAutoRefCnt mDBRefCnt;
   ThreadSafeAutoRefCnt mSliceRefCnt;
 
-  RefPtr<FileManager> mFileManager;
+  const RefPtr<FileManager> mFileManager;
 
  public:
   class CustomCleanupCallback;
 
-  static FileInfo* Create(FileManager* aFileManager, int64_t aId);
-
-  explicit FileInfo(FileManager* aFileManager);
+  FileInfo(RefPtr<FileManager> aFileManager, const int64_t aFileId,
+           const nsrefcnt aInitialDBRefCnt = 0)
+      : mFileId(aFileId),
+        mDBRefCnt(aInitialDBRefCnt),
+        mFileManager(std::move(aFileManager)) {
+    MOZ_ASSERT(mFileManager);
+    MOZ_ASSERT(mFileId > 0);
+  }
 
   void AddRef() { UpdateReferences(mRefCnt, 1); }
 
@@ -48,13 +55,10 @@ class FileInfo {
 
   FileManager* Manager() const { return mFileManager; }
 
-  virtual int64_t Id() const = 0;
+  int64_t Id() const { return mFileId; }
 
   static nsCOMPtr<nsIFile> GetFileForFileInfo(FileInfo* aFileInfo);
 
- protected:
-  virtual ~FileInfo() = default;
-
  private:
   void UpdateReferences(
       ThreadSafeAutoRefCnt& aRefCount, int32_t aDelta,