/* 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/. */ #ifndef nsHtml5AtomTable_h #define nsHtml5AtomTable_h #include "nsHashKeys.h" #include "nsTHashtable.h" #include "nsAtom.h" #include "nsISerialEventTarget.h" #define RECENTLY_USED_PARSER_ATOMS_SIZE 37 /* * nsHtml5AtomTable provides an atom cache for nsHtml5Parser and * nsHtml5StreamParser. * * An instance of nsHtml5AtomTable that belongs to an nsHtml5Parser is only * accessed from the main thread. An instance of nsHtml5AtomTable that belongs * to an nsHtml5StreamParser is accessed both from the main thread and from the * thread that executes the runnables of the nsHtml5StreamParser instance. * However, the threads never access the nsHtml5AtomTable instance concurrently * in the nsHtml5StreamParser case. * * Methods on the atoms obtained from nsHtml5AtomTable may be called on any * thread, although they only need to be called on the main thread or on the * thread working for the nsHtml5StreamParser when nsHtml5AtomTable belongs to * an nsHtml5StreamParser. * * Atoms cached by nsHtml5AtomTable are released when Clear() is called or when * the nsHtml5AtomTable itself is destructed, which happens when the owner * nsHtml5Parser or nsHtml5StreamParser is destructed. */ class nsHtml5AtomTable { public: nsHtml5AtomTable(); ~nsHtml5AtomTable(); // NOTE: We rely on mRecentlyUsedParserAtoms keeping alive the returned atom, // but the caller is responsible to take a reference before calling GetAtom // again. nsAtom* GetAtom(const nsAString& aKey); /** * Empties the table. */ void Clear() { for (uint32_t i = 0; i < RECENTLY_USED_PARSER_ATOMS_SIZE; ++i) { mRecentlyUsedParserAtoms[i] = nullptr; } } #ifdef DEBUG void SetPermittedLookupEventTarget(nsISerialEventTarget* aEventTarget) { mPermittedLookupEventTarget = aEventTarget; } #endif private: RefPtr<nsAtom> mRecentlyUsedParserAtoms[RECENTLY_USED_PARSER_ATOMS_SIZE]; #ifdef DEBUG nsCOMPtr<nsISerialEventTarget> mPermittedLookupEventTarget; #endif }; #endif // nsHtml5AtomTable_h