1 /* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef ART_RUNTIME_JDWP_OBJECT_REGISTRY_H_ 18 #define ART_RUNTIME_JDWP_OBJECT_REGISTRY_H_ 19 20 #include <jni.h> 21 #include <stdint.h> 22 23 #include <map> 24 25 #include "base/casts.h" 26 #include "handle.h" 27 #include "jdwp/jdwp.h" 28 #include "safe_map.h" 29 30 namespace art { 31 32 namespace mirror { 33 class Object; 34 class Class; 35 } // namespace mirror 36 37 struct ObjectRegistryEntry { 38 // Is jni_reference a weak global or a regular global reference? 39 jobjectRefType jni_reference_type; 40 41 // The reference itself. 42 jobject jni_reference; 43 44 // A reference count, so we can implement DisposeObject. 45 int32_t reference_count; 46 47 // The corresponding id, so we only need one map lookup in Add. 48 JDWP::ObjectId id; 49 50 // The identity hash code of the object. This is the same as the key 51 // for object_to_entry_. Store this for DisposeObject(). 52 int32_t identity_hash_code; 53 }; 54 std::ostream& operator<<(std::ostream& os, const ObjectRegistryEntry& rhs); 55 56 // Tracks those objects currently known to the debugger, so we can use consistent ids when 57 // referring to them. Normally we keep JNI weak global references to objects, so they can 58 // still be garbage collected. The debugger can ask us to retain objects, though, so we can 59 // also promote references to regular JNI global references (and demote them back again if 60 // the debugger tells us that's okay). 61 class ObjectRegistry { 62 public: 63 ObjectRegistry(); 64 65 JDWP::ObjectId Add(mirror::Object* o) 66 SHARED_REQUIRES(Locks::mutator_lock_) 67 REQUIRES(!Locks::thread_list_lock_, !Locks::thread_suspend_count_lock_, !lock_); 68 69 JDWP::RefTypeId AddRefType(mirror::Class* c) 70 SHARED_REQUIRES(Locks::mutator_lock_) 71 REQUIRES(!Locks::thread_list_lock_, !Locks::thread_suspend_count_lock_, !lock_); 72 73 template<class T> 74 JDWP::ObjectId Add(Handle<T> obj_h) 75 SHARED_REQUIRES(Locks::mutator_lock_) 76 REQUIRES(!Locks::thread_list_lock_, !Locks::thread_suspend_count_lock_, !lock_); 77 78 JDWP::RefTypeId AddRefType(Handle<mirror::Class> c_h) 79 SHARED_REQUIRES(Locks::mutator_lock_) 80 REQUIRES(!Locks::thread_list_lock_, !Locks::thread_suspend_count_lock_, !lock_); 81 Get(JDWP::ObjectId id,JDWP::JdwpError * error)82 template<typename T> T Get(JDWP::ObjectId id, JDWP::JdwpError* error) 83 SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!lock_) { 84 if (id == 0) { 85 *error = JDWP::ERR_NONE; 86 return nullptr; 87 } 88 return down_cast<T>(InternalGet(id, error)); 89 } 90 91 void Clear() SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!lock_); 92 93 void DisableCollection(JDWP::ObjectId id) 94 SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!lock_); 95 96 void EnableCollection(JDWP::ObjectId id) 97 SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!lock_); 98 99 bool IsCollected(JDWP::ObjectId id) 100 SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!lock_); 101 102 void DisposeObject(JDWP::ObjectId id, uint32_t reference_count) 103 SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!lock_); 104 105 // This is needed to get the jobject instead of the Object*. 106 // Avoid using this and use standard Get when possible. 107 jobject GetJObject(JDWP::ObjectId id) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!lock_); 108 109 private: 110 template<class T> 111 JDWP::ObjectId InternalAdd(Handle<T> obj_h) 112 SHARED_REQUIRES(Locks::mutator_lock_) 113 REQUIRES(!lock_, !Locks::thread_list_lock_, !Locks::thread_suspend_count_lock_); 114 115 mirror::Object* InternalGet(JDWP::ObjectId id, JDWP::JdwpError* error) 116 SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!lock_); 117 118 void Demote(ObjectRegistryEntry& entry) 119 SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(lock_); 120 121 void Promote(ObjectRegistryEntry& entry) 122 SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(lock_); 123 124 bool ContainsLocked(Thread* self, mirror::Object* o, int32_t identity_hash_code, 125 ObjectRegistryEntry** out_entry) 126 REQUIRES(lock_) SHARED_REQUIRES(Locks::mutator_lock_); 127 128 Mutex lock_ DEFAULT_MUTEX_ACQUIRED_AFTER; 129 std::multimap<int32_t, ObjectRegistryEntry*> object_to_entry_ GUARDED_BY(lock_); 130 SafeMap<JDWP::ObjectId, ObjectRegistryEntry*> id_to_entry_ GUARDED_BY(lock_); 131 132 size_t next_id_ GUARDED_BY(lock_); 133 }; 134 135 } // namespace art 136 137 #endif // ART_RUNTIME_JDWP_OBJECT_REGISTRY_H_ 138