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 "gc_root-inl.h"
23 #include "runtime-inl.h"
24 #include "verify_object-inl.h"
25 
26 namespace art {
27 namespace mirror {
28 class Object;
29 }  // namespace mirror
30 
31 // Verifies that the indirect table lookup is valid.
32 // Returns "false" if something looks bad.
GetChecked(IndirectRef iref)33 inline bool IndirectReferenceTable::GetChecked(IndirectRef iref) const {
34   if (UNLIKELY(iref == nullptr)) {
35     LOG(WARNING) << "Attempt to look up nullptr " << kind_;
36     return false;
37   }
38   if (UNLIKELY(GetIndirectRefKind(iref) == kHandleScopeOrInvalid)) {
39     LOG(ERROR) << "JNI ERROR (app bug): invalid " << kind_ << " " << iref;
40     AbortIfNoCheckJNI();
41     return false;
42   }
43   const int topIndex = segment_state_.parts.topIndex;
44   int idx = ExtractIndex(iref);
45   if (UNLIKELY(idx >= topIndex)) {
46     LOG(ERROR) << "JNI ERROR (app bug): accessed stale " << kind_ << " "
47                << iref << " (index " << idx << " in a table of size " << topIndex << ")";
48     AbortIfNoCheckJNI();
49     return false;
50   }
51   if (UNLIKELY(table_[idx].GetReference()->IsNull())) {
52     LOG(ERROR) << "JNI ERROR (app bug): accessed deleted " << kind_ << " " << iref;
53     AbortIfNoCheckJNI();
54     return false;
55   }
56   if (UNLIKELY(!CheckEntry("use", iref, idx))) {
57     return false;
58   }
59   return true;
60 }
61 
62 // Make sure that the entry at "idx" is correctly paired with "iref".
CheckEntry(const char * what,IndirectRef iref,int idx)63 inline bool IndirectReferenceTable::CheckEntry(const char* what, IndirectRef iref, int idx) const {
64   IndirectRef checkRef = ToIndirectRef(idx);
65   if (UNLIKELY(checkRef != iref)) {
66     LOG(ERROR) << "JNI ERROR (app bug): attempt to " << what
67                << " stale " << kind_ << " " << iref
68                << " (should be " << checkRef << ")";
69     AbortIfNoCheckJNI();
70     return false;
71   }
72   return true;
73 }
74 
75 template<ReadBarrierOption kReadBarrierOption>
Get(IndirectRef iref)76 inline mirror::Object* IndirectReferenceTable::Get(IndirectRef iref) const {
77   if (!GetChecked(iref)) {
78     return nullptr;
79   }
80   uint32_t idx = ExtractIndex(iref);
81   mirror::Object* obj = table_[idx].GetReference()->Read<kReadBarrierOption>();
82   VerifyObject(obj);
83   return obj;
84 }
85 
Update(IndirectRef iref,mirror::Object * obj)86 inline void IndirectReferenceTable::Update(IndirectRef iref, mirror::Object* obj) {
87   if (!GetChecked(iref)) {
88     LOG(WARNING) << "IndirectReferenceTable Update failed to find reference " << iref;
89     return;
90   }
91   uint32_t idx = ExtractIndex(iref);
92   table_[idx].SetReference(obj);
93 }
94 
95 }  // namespace art
96 
97 #endif  // ART_RUNTIME_INDIRECT_REFERENCE_TABLE_INL_H_
98