1 /*
2  * Copyright (C) 2014 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_INDIRECT_REFERENCE_TABLE_INL_H_
18 #define ART_RUNTIME_INDIRECT_REFERENCE_TABLE_INL_H_
19 
20 #include "indirect_reference_table.h"
21 
22 #include "android-base/stringprintf.h"
23 
24 #include "base/dumpable.h"
25 #include "gc_root-inl.h"
26 #include "obj_ptr-inl.h"
27 #include "verify_object.h"
28 
29 namespace art {
30 namespace mirror {
31 class Object;
32 }  // namespace mirror
33 
34 // Verifies that the indirect table lookup is valid.
35 // Returns "false" if something looks bad.
GetChecked(IndirectRef iref)36 inline bool IndirectReferenceTable::GetChecked(IndirectRef iref) const {
37   if (UNLIKELY(iref == nullptr)) {
38     LOG(WARNING) << "Attempt to look up nullptr " << kind_;
39     return false;
40   }
41   if (UNLIKELY(GetIndirectRefKind(iref) == kHandleScopeOrInvalid)) {
42     AbortIfNoCheckJNI(android::base::StringPrintf("JNI ERROR (app bug): invalid %s %p",
43                                                   GetIndirectRefKindString(kind_),
44                                                   iref));
45     return false;
46   }
47   const uint32_t top_index = segment_state_.top_index;
48   uint32_t idx = ExtractIndex(iref);
49   if (UNLIKELY(idx >= top_index)) {
50     std::string msg = android::base::StringPrintf(
51         "JNI ERROR (app bug): accessed stale %s %p  (index %d in a table of size %d)",
52         GetIndirectRefKindString(kind_),
53         iref,
54         idx,
55         top_index);
56     AbortIfNoCheckJNI(msg);
57     return false;
58   }
59   if (UNLIKELY(table_[idx].GetReference()->IsNull())) {
60     AbortIfNoCheckJNI(android::base::StringPrintf("JNI ERROR (app bug): accessed deleted %s %p",
61                                                   GetIndirectRefKindString(kind_),
62                                                   iref));
63     return false;
64   }
65   if (UNLIKELY(!CheckEntry("use", iref, idx))) {
66     return false;
67   }
68   return true;
69 }
70 
71 // Make sure that the entry at "idx" is correctly paired with "iref".
CheckEntry(const char * what,IndirectRef iref,uint32_t idx)72 inline bool IndirectReferenceTable::CheckEntry(const char* what,
73                                                IndirectRef iref,
74                                                uint32_t idx) const {
75   IndirectRef checkRef = ToIndirectRef(idx);
76   if (UNLIKELY(checkRef != iref)) {
77     std::string msg = android::base::StringPrintf(
78         "JNI ERROR (app bug): attempt to %s stale %s %p (should be %p)",
79         what,
80         GetIndirectRefKindString(kind_),
81         iref,
82         checkRef);
83     AbortIfNoCheckJNI(msg);
84     return false;
85   }
86   return true;
87 }
88 
89 template<ReadBarrierOption kReadBarrierOption>
Get(IndirectRef iref)90 inline ObjPtr<mirror::Object> IndirectReferenceTable::Get(IndirectRef iref) const {
91   if (!GetChecked(iref)) {
92     return nullptr;
93   }
94   uint32_t idx = ExtractIndex(iref);
95   ObjPtr<mirror::Object> obj = table_[idx].GetReference()->Read<kReadBarrierOption>();
96   VerifyObject(obj);
97   return obj;
98 }
99 
Update(IndirectRef iref,ObjPtr<mirror::Object> obj)100 inline void IndirectReferenceTable::Update(IndirectRef iref, ObjPtr<mirror::Object> obj) {
101   if (!GetChecked(iref)) {
102     LOG(WARNING) << "IndirectReferenceTable Update failed to find reference " << iref;
103     return;
104   }
105   uint32_t idx = ExtractIndex(iref);
106   table_[idx].SetReference(obj);
107 }
108 
Add(ObjPtr<mirror::Object> obj)109 inline void IrtEntry::Add(ObjPtr<mirror::Object> obj) {
110   ++serial_;
111   if (serial_ == kIRTPrevCount) {
112     serial_ = 0;
113   }
114   references_[serial_] = GcRoot<mirror::Object>(obj);
115 }
116 
SetReference(ObjPtr<mirror::Object> obj)117 inline void IrtEntry::SetReference(ObjPtr<mirror::Object> obj) {
118   DCHECK_LT(serial_, kIRTPrevCount);
119   references_[serial_] = GcRoot<mirror::Object>(obj);
120 }
121 
122 }  // namespace art
123 
124 #endif  // ART_RUNTIME_INDIRECT_REFERENCE_TABLE_INL_H_
125