1 /*
2  * Copyright (C) 2016 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 "common_helper.h"
18 
19 #include <sstream>
20 #include <string>
21 
22 #include "android-base/stringprintf.h"
23 #include "jni.h"
24 #include "jvmti.h"
25 
26 #include "jvmti_helper.h"
27 #include "ti_macros.h"
28 
29 namespace art {
30 
GetJavaField(jvmtiEnv * jvmti,JNIEnv * env,jclass field_klass,jfieldID f)31 jobject GetJavaField(jvmtiEnv* jvmti, JNIEnv* env, jclass field_klass, jfieldID f) {
32   jint mods = 0;
33   if (JvmtiErrorToException(env, jvmti, jvmti->GetFieldModifiers(field_klass, f, &mods))) {
34     return nullptr;
35   }
36 
37   bool is_static = (mods & kAccStatic) != 0;
38   return env->ToReflectedField(field_klass, f, is_static);
39 }
40 
GetJavaMethod(jvmtiEnv * jvmti,JNIEnv * env,jmethodID m)41 jobject GetJavaMethod(jvmtiEnv* jvmti, JNIEnv* env, jmethodID m) {
42   jint mods = 0;
43   if (JvmtiErrorToException(env, jvmti, jvmti->GetMethodModifiers(m, &mods))) {
44     return nullptr;
45   }
46 
47   bool is_static = (mods & kAccStatic) != 0;
48   jclass method_klass = nullptr;
49   if (JvmtiErrorToException(env, jvmti, jvmti->GetMethodDeclaringClass(m, &method_klass))) {
50     return nullptr;
51   }
52   jobject res = env->ToReflectedMethod(method_klass, m, is_static);
53   env->DeleteLocalRef(method_klass);
54   return res;
55 }
56 
GetJavaValueByType(JNIEnv * env,char type,jvalue value)57 jobject GetJavaValueByType(JNIEnv* env, char type, jvalue value) {
58   std::string name;
59   switch (type) {
60     case 'V':
61       return nullptr;
62     case '[':
63     case 'L':
64       return value.l;
65     case 'Z':
66       name = "java/lang/Boolean";
67       break;
68     case 'B':
69       name = "java/lang/Byte";
70       break;
71     case 'C':
72       name = "java/lang/Character";
73       break;
74     case 'S':
75       name = "java/lang/Short";
76       break;
77     case 'I':
78       name = "java/lang/Integer";
79       break;
80     case 'J':
81       name = "java/lang/Long";
82       break;
83     case 'F':
84       name = "java/lang/Float";
85       break;
86     case 'D':
87       name = "java/lang/Double";
88       break;
89     default:
90       LOG(FATAL) << "Unable to figure out type!";
91       UNREACHABLE();
92   }
93   std::ostringstream oss;
94   oss << "(" << type << ")L" << name << ";";
95   std::string args = oss.str();
96   jclass target = env->FindClass(name.c_str());
97   jmethodID valueOfMethod = env->GetStaticMethodID(target, "valueOf", args.c_str());
98 
99   CHECK(valueOfMethod != nullptr) << args;
100   jobject res = env->CallStaticObjectMethodA(target, valueOfMethod, &value);
101   env->DeleteLocalRef(target);
102   return res;
103 }
104 
GetJavaValue(jvmtiEnv * jvmtienv,JNIEnv * env,jmethodID m,jvalue value)105 jobject GetJavaValue(jvmtiEnv* jvmtienv, JNIEnv* env, jmethodID m, jvalue value) {
106   char *fname, *fsig, *fgen;
107   if (JvmtiErrorToException(env, jvmtienv, jvmtienv->GetMethodName(m, &fname, &fsig, &fgen))) {
108     return nullptr;
109   }
110   std::string type(fsig);
111   type = type.substr(type.find(')') + 1);
112   jvmtienv->Deallocate(reinterpret_cast<unsigned char*>(fsig));
113   jvmtienv->Deallocate(reinterpret_cast<unsigned char*>(fname));
114   jvmtienv->Deallocate(reinterpret_cast<unsigned char*>(fgen));
115   return GetJavaValueByType(env, type[0], value);
116 }
117 
118 }  // namespace art
119