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 "base/safe_map.h" 27 #include "handle.h" 28 #include "jdwp/jdwp.h" 29 #include "obj_ptr.h" 30 31 namespace art { 32 33 namespace mirror { 34 class Object; 35 class Class; 36 } // namespace mirror 37 38 struct ObjectRegistryEntry { 39 // Is jni_reference a weak global or a regular global reference? 40 jobjectRefType jni_reference_type; 41 42 // The reference itself. 43 jobject jni_reference; 44 45 // A reference count, so we can implement DisposeObject. 46 int32_t reference_count; 47 48 // The corresponding id, so we only need one map lookup in Add. 49 JDWP::ObjectId id; 50 51 // The identity hash code of the object. This is the same as the key 52 // for object_to_entry_. Store this for DisposeObject(). 53 int32_t identity_hash_code; 54 }; 55 std::ostream& operator<<(std::ostream& os, const ObjectRegistryEntry& rhs); 56 57 // Tracks those objects currently known to the debugger, so we can use consistent ids when 58 // referring to them. Normally we keep JNI weak global references to objects, so they can 59 // still be garbage collected. The debugger can ask us to retain objects, though, so we can 60 // also promote references to regular JNI global references (and demote them back again if 61 // the debugger tells us that's okay). 62 class ObjectRegistry { 63 public: 64 ObjectRegistry(); 65 ~ObjectRegistry(); 66 67 JDWP::ObjectId Add(ObjPtr<mirror::Object> o) 68 REQUIRES_SHARED(Locks::mutator_lock_) 69 REQUIRES(!Locks::thread_list_lock_, !Locks::thread_suspend_count_lock_, !lock_); 70 71 JDWP::RefTypeId AddRefType(ObjPtr<mirror::Class> c) 72 REQUIRES_SHARED(Locks::mutator_lock_) 73 REQUIRES(!Locks::thread_list_lock_, !Locks::thread_suspend_count_lock_, !lock_); 74 75 template<class T> 76 JDWP::ObjectId Add(Handle<T> obj_h) 77 REQUIRES_SHARED(Locks::mutator_lock_) 78 REQUIRES(!Locks::thread_list_lock_, !Locks::thread_suspend_count_lock_, !lock_); 79 80 JDWP::RefTypeId AddRefType(Handle<mirror::Class> c_h) 81 REQUIRES_SHARED(Locks::mutator_lock_) 82 REQUIRES(!Locks::thread_list_lock_, !Locks::thread_suspend_count_lock_, !lock_); 83 Get(JDWP::ObjectId id,JDWP::JdwpError * error)84 template<typename T> T Get(JDWP::ObjectId id, JDWP::JdwpError* error) 85 REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!lock_) { 86 if (id == 0) { 87 *error = JDWP::ERR_NONE; 88 return nullptr; 89 } 90 return down_cast<T>(InternalGet(id, error)); 91 } 92 93 void Clear() REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!lock_); 94 95 void DisableCollection(JDWP::ObjectId id) 96 REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!lock_); 97 98 void EnableCollection(JDWP::ObjectId id) 99 REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!lock_); 100 101 bool IsCollected(JDWP::ObjectId id) 102 REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!lock_); 103 104 void DisposeObject(JDWP::ObjectId id, uint32_t reference_count) 105 REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!lock_); 106 107 // This is needed to get the jobject instead of the Object*. 108 // Avoid using this and use standard Get when possible. 109 jobject GetJObject(JDWP::ObjectId id) REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!lock_); 110 111 private: 112 template<class T> 113 JDWP::ObjectId InternalAdd(Handle<T> obj_h) 114 REQUIRES_SHARED(Locks::mutator_lock_) 115 REQUIRES(!lock_, !Locks::thread_list_lock_, !Locks::thread_suspend_count_lock_); 116 117 mirror::Object* InternalGet(JDWP::ObjectId id, JDWP::JdwpError* error) 118 REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!lock_); 119 120 void Demote(ObjectRegistryEntry& entry) 121 REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(lock_); 122 123 void Promote(ObjectRegistryEntry& entry) 124 REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(lock_); 125 126 bool ContainsLocked(Thread* self, 127 ObjPtr<mirror::Object> o, 128 int32_t identity_hash_code, 129 ObjectRegistryEntry** out_entry) 130 REQUIRES(lock_) REQUIRES_SHARED(Locks::mutator_lock_); 131 132 Mutex lock_ DEFAULT_MUTEX_ACQUIRED_AFTER; 133 std::multimap<int32_t, ObjectRegistryEntry*> object_to_entry_ GUARDED_BY(lock_); 134 SafeMap<JDWP::ObjectId, ObjectRegistryEntry*> id_to_entry_ GUARDED_BY(lock_); 135 136 size_t next_id_ GUARDED_BY(lock_); 137 }; 138 139 } // namespace art 140 141 #endif // ART_RUNTIME_JDWP_OBJECT_REGISTRY_H_ 142