| /* |
| * Copyright (C) 2011 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef ART_RUNTIME_INTERN_TABLE_H_ |
| #define ART_RUNTIME_INTERN_TABLE_H_ |
| |
| #include <map> |
| |
| #include "base/mutex.h" |
| #include "object_callbacks.h" |
| |
| namespace art { |
| |
| enum VisitRootFlags : uint8_t; |
| |
| namespace mirror { |
| class String; |
| } // namespace mirror |
| class Transaction; |
| |
| /** |
| * Used to intern strings. |
| * |
| * There are actually two tables: one that holds strong references to its strings, and one that |
| * holds weak references. The former is used for string literals, for which there is an effective |
| * reference from the constant pool. The latter is used for strings interned at runtime via |
| * String.intern. Some code (XML parsers being a prime example) relies on being able to intern |
| * arbitrarily many strings for the duration of a parse without permanently increasing the memory |
| * footprint. |
| */ |
| class InternTable { |
| public: |
| InternTable(); |
| |
| // Interns a potentially new string in the 'strong' table. (See above.) |
| mirror::String* InternStrong(int32_t utf16_length, const char* utf8_data) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| // Interns a potentially new string in the 'strong' table. (See above.) |
| mirror::String* InternStrong(const char* utf8_data) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| // Interns a potentially new string in the 'strong' table. (See above.) |
| mirror::String* InternStrong(mirror::String* s) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| // Interns a potentially new string in the 'weak' table. (See above.) |
| mirror::String* InternWeak(mirror::String* s) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| void SweepInternTableWeaks(IsMarkedCallback* callback, void* arg); |
| |
| bool ContainsWeak(mirror::String* s) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| size_t Size() const; |
| |
| void VisitRoots(RootCallback* callback, void* arg, VisitRootFlags flags); |
| |
| void DumpForSigQuit(std::ostream& os) const; |
| |
| void DisallowNewInterns() EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_); |
| void AllowNewInterns() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| private: |
| typedef std::multimap<int32_t, mirror::String*> Table; |
| |
| mirror::String* Insert(mirror::String* s, bool is_strong) |
| LOCKS_EXCLUDED(Locks::intern_table_lock_) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| mirror::String* LookupStrong(mirror::String* s, int32_t hash_code) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| mirror::String* LookupWeak(mirror::String* s, int32_t hash_code) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| template<ReadBarrierOption kReadBarrierOption = kWithReadBarrier> |
| mirror::String* Lookup(Table* table, mirror::String* s, int32_t hash_code) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| mirror::String* InsertStrong(mirror::String* s, int32_t hash_code) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::intern_table_lock_); |
| mirror::String* InsertWeak(mirror::String* s, int32_t hash_code) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::intern_table_lock_); |
| void RemoveStrong(mirror::String* s, int32_t hash_code) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::intern_table_lock_); |
| void RemoveWeak(mirror::String* s, int32_t hash_code) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::intern_table_lock_); |
| template<ReadBarrierOption kReadBarrierOption = kWithReadBarrier> |
| void Remove(Table* table, mirror::String* s, int32_t hash_code) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::intern_table_lock_); |
| |
| // Transaction rollback access. |
| mirror::String* InsertStrongFromTransaction(mirror::String* s, int32_t hash_code) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::intern_table_lock_); |
| mirror::String* InsertWeakFromTransaction(mirror::String* s, int32_t hash_code) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::intern_table_lock_); |
| void RemoveStrongFromTransaction(mirror::String* s, int32_t hash_code) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::intern_table_lock_); |
| void RemoveWeakFromTransaction(mirror::String* s, int32_t hash_code) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::intern_table_lock_); |
| friend class Transaction; |
| |
| bool log_new_roots_ GUARDED_BY(Locks::intern_table_lock_); |
| bool allow_new_interns_ GUARDED_BY(Locks::intern_table_lock_); |
| ConditionVariable new_intern_condition_ GUARDED_BY(Locks::intern_table_lock_); |
| Table strong_interns_ GUARDED_BY(Locks::intern_table_lock_); |
| std::vector<std::pair<int32_t, mirror::String*>> new_strong_intern_roots_ |
| GUARDED_BY(Locks::intern_table_lock_); |
| // Since weak_interns_ contain weak roots, they need a read |
| // barrier. Do not directly access the strings in it. Use functions |
| // that contain read barriers. |
| Table weak_interns_ GUARDED_BY(Locks::intern_table_lock_); |
| }; |
| |
| } // namespace art |
| |
| #endif // ART_RUNTIME_INTERN_TABLE_H_ |