1 /*
2  * Copyright (C) 2018 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 #include <sstream>
18 
19 #include "debug_print.h"
20 
21 #include "class_linker.h"
22 #include "class_table.h"
23 #include "class_loader_utils.h"
24 #include "dex/utf.h"
25 #include "gc/heap.h"
26 #include "gc/space/space-inl.h"
27 #include "mirror/class.h"
28 #include "mirror/class_loader-inl.h"
29 #include "runtime.h"
30 #include "scoped_thread_state_change-inl.h"
31 #include "thread-current-inl.h"
32 #include "well_known_classes-inl.h"
33 
34 namespace art HIDDEN {
35 
DescribeSpace(ObjPtr<mirror::Class> klass)36 std::string DescribeSpace(ObjPtr<mirror::Class> klass) {
37   std::ostringstream oss;
38   gc::Heap* heap = Runtime::Current()->GetHeap();
39   gc::space::ContinuousSpace* cs =
40       heap->FindContinuousSpaceFromObject(klass, /* fail_ok= */ true);
41   if (cs != nullptr) {
42     if (cs->IsImageSpace()) {
43       gc::space::ImageSpace* ispace = cs->AsImageSpace();
44       oss << "image;" << ispace->GetName() << ";"
45           // If the file name is the same as the name, output "+" instead to shorten the output.
46           << (ispace->GetImageFilename() == cs->GetName() ? "+" : ispace->GetImageFilename())
47           << ";" << static_cast<const void*>(ispace->Begin());
48     } else {
49       oss << "continuous;" << cs->GetName();
50     }
51   } else {
52     gc::space::DiscontinuousSpace* ds =
53         heap->FindDiscontinuousSpaceFromObject(klass, /* fail_ok= */ true);
54     if (ds != nullptr) {
55       oss << "discontinuous;" << ds->GetName();
56     } else {
57       oss << "invalid";
58     }
59   }
60   return oss.str();
61 }
62 
DescribeLoaders(ObjPtr<mirror::ClassLoader> loader,const char * class_descriptor)63 std::string DescribeLoaders(ObjPtr<mirror::ClassLoader> loader, const char* class_descriptor) {
64   std::ostringstream oss;
65   uint32_t hash = ComputeModifiedUtf8Hash(class_descriptor);
66   ObjPtr<mirror::Class> path_class_loader = WellKnownClasses::dalvik_system_PathClassLoader.Get();
67   ObjPtr<mirror::Class> dex_class_loader = WellKnownClasses::dalvik_system_DexClassLoader.Get();
68   ObjPtr<mirror::Class> delegate_last_class_loader =
69       WellKnownClasses::dalvik_system_DelegateLastClassLoader.Get();
70 
71   // Print the class loader chain.
72   bool found_class = false;
73   const char* loader_separator = "";
74   if (loader == nullptr) {
75     oss << "BootClassLoader";  // This would be unexpected.
76   }
77   for (; loader != nullptr; loader = loader->GetParent()) {
78     ClassTable* table = Runtime::Current()->GetClassLinker()->ClassTableForClassLoader(loader);
79     oss << loader_separator << loader->GetClass()->PrettyDescriptor()
80         << "/" << static_cast<const void*>(table);
81     loader_separator = ";";
82     // If we didn't find the class yet, try to find it in the current class loader.
83     if (!found_class) {
84       ObjPtr<mirror::Class> klass =
85           (table != nullptr) ? table->Lookup(class_descriptor, hash) : nullptr;
86       if (klass != nullptr) {
87         found_class = true;
88         oss << "[hit:" << DescribeSpace(klass) << "]";
89       }
90     }
91 
92     // For PathClassLoader, DexClassLoader or DelegateLastClassLoader
93     // also dump the dex file locations.
94     if (loader->GetClass() == path_class_loader ||
95         loader->GetClass() == dex_class_loader ||
96         loader->GetClass() == delegate_last_class_loader) {
97       oss << "(";
98       Thread* self = Thread::Current();
99       StackHandleScope<1> hs(self);
100       Handle<mirror::ClassLoader> handle(hs.NewHandle(loader));
101       const char* path_separator = "";
102       const DexFile* base_dex_file = nullptr;
103       VisitClassLoaderDexFiles(
104           self,
105           handle,
106           [&](const DexFile* dex_file) {
107               oss << path_separator;
108               path_separator = ":";
109               if (base_dex_file != nullptr &&
110                   dex_file->GetLocation().length() > base_dex_file->GetLocation().length() &&
111                   dex_file->GetLocation().compare(0u,
112                                                   base_dex_file->GetLocation().length(),
113                                                   base_dex_file->GetLocation()) == 0) {
114                 // Replace the base location with "+" to shorten the output.
115                 oss << "+" << dex_file->GetLocation().substr(base_dex_file->GetLocation().length());
116               } else {
117                 oss << dex_file->GetLocation();
118                 base_dex_file = dex_file;
119               }
120               oss << "/" << static_cast<const void*>(dex_file);
121               return true;  // Continue with the next DexFile.
122           });
123       oss << ")";
124     }
125   }
126 
127   return oss.str();
128 }
129 
130 }  // namespace art
131