1 /*
2 * Copyright (C) 2008 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 "class_linker.h"
18 #include "jni_internal.h"
19 #include "mirror/class_loader.h"
20 #include "mirror/object-inl.h"
21 #include "scoped_fast_native_object_access.h"
22 #include "ScopedUtfChars.h"
23 #include "zip_archive.h"
24
25 namespace art {
26
VMClassLoader_findLoadedClass(JNIEnv * env,jclass,jobject javaLoader,jstring javaName)27 static jclass VMClassLoader_findLoadedClass(JNIEnv* env, jclass, jobject javaLoader, jstring javaName) {
28 ScopedFastNativeObjectAccess soa(env);
29 mirror::ClassLoader* loader = soa.Decode<mirror::ClassLoader*>(javaLoader);
30 ScopedUtfChars name(env, javaName);
31 if (name.c_str() == nullptr) {
32 return nullptr;
33 }
34 ClassLinker* cl = Runtime::Current()->GetClassLinker();
35 std::string descriptor(DotToDescriptor(name.c_str()));
36 const size_t descriptor_hash = ComputeModifiedUtf8Hash(descriptor.c_str());
37 mirror::Class* c = cl->LookupClass(descriptor.c_str(), descriptor_hash, loader);
38 if (c != nullptr && c->IsResolved()) {
39 return soa.AddLocalReference<jclass>(c);
40 }
41 if (loader != nullptr) {
42 // Try the common case.
43 StackHandleScope<1> hs(soa.Self());
44 c = cl->FindClassInPathClassLoader(soa, soa.Self(), descriptor.c_str(), descriptor_hash,
45 hs.NewHandle(loader));
46 if (c != nullptr) {
47 return soa.AddLocalReference<jclass>(c);
48 }
49 }
50 // Class wasn't resolved so it may be erroneous or not yet ready, force the caller to go into
51 // the regular loadClass code.
52 return nullptr;
53 }
54
VMClassLoader_getBootClassPathSize(JNIEnv *,jclass)55 static jint VMClassLoader_getBootClassPathSize(JNIEnv*, jclass) {
56 return Runtime::Current()->GetClassLinker()->GetBootClassPath().size();
57 }
58
59 /*
60 * Returns a string URL for a resource with the specified 'javaName' in
61 * entry 'index' of the boot class path.
62 *
63 * We return a newly-allocated String in the following form:
64 *
65 * jar:file://path!/name
66 *
67 * Where "path" is the bootstrap class path entry and "name" is the string
68 * passed into this method. "path" needs to be an absolute path (starting
69 * with '/'); if it's not we'd need to make it absolute as part of forming
70 * the URL string.
71 */
VMClassLoader_getBootClassPathResource(JNIEnv * env,jclass,jstring javaName,jint index)72 static jstring VMClassLoader_getBootClassPathResource(JNIEnv* env, jclass, jstring javaName, jint index) {
73 ScopedUtfChars name(env, javaName);
74 if (name.c_str() == nullptr) {
75 return nullptr;
76 }
77
78 const std::vector<const DexFile*>& path = Runtime::Current()->GetClassLinker()->GetBootClassPath();
79 if (index < 0 || size_t(index) >= path.size()) {
80 return nullptr;
81 }
82 const DexFile* dex_file = path[index];
83
84 // For multidex locations, e.g., x.jar:classes2.dex, we want to look into x.jar.
85 const std::string& location(dex_file->GetBaseLocation());
86
87 std::string error_msg;
88 std::unique_ptr<ZipArchive> zip_archive(ZipArchive::Open(location.c_str(), &error_msg));
89 if (zip_archive.get() == nullptr) {
90 LOG(WARNING) << "Failed to open zip archive '" << location << "': " << error_msg;
91 return nullptr;
92 }
93 std::unique_ptr<ZipEntry> zip_entry(zip_archive->Find(name.c_str(), &error_msg));
94 if (zip_entry.get() == nullptr) {
95 return nullptr;
96 }
97
98 std::string url;
99 StringAppendF(&url, "jar:file://%s!/%s", location.c_str(), name.c_str());
100 return env->NewStringUTF(url.c_str());
101 }
102
103 static JNINativeMethod gMethods[] = {
104 NATIVE_METHOD(VMClassLoader, findLoadedClass, "!(Ljava/lang/ClassLoader;Ljava/lang/String;)Ljava/lang/Class;"),
105 NATIVE_METHOD(VMClassLoader, getBootClassPathResource, "(Ljava/lang/String;I)Ljava/lang/String;"),
106 NATIVE_METHOD(VMClassLoader, getBootClassPathSize, "!()I"),
107 };
108
register_java_lang_VMClassLoader(JNIEnv * env)109 void register_java_lang_VMClassLoader(JNIEnv* env) {
110 REGISTER_NATIVE_METHODS("java/lang/VMClassLoader");
111 }
112
113 } // namespace art
114