1 /* Copyright (C) 2016 The Android Open Source Project
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This file implements interfaces from the file jvmti.h. This implementation
5 * is licensed under the same terms as the file jvmti.h. The
6 * copyright and license information for the file jvmti.h follows.
7 *
8 * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
9 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
10 *
11 * This code is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License version 2 only, as
13 * published by the Free Software Foundation. Oracle designates this
14 * particular file as subject to the "Classpath" exception as provided
15 * by Oracle in the LICENSE file that accompanied this code.
16 *
17 * This code is distributed in the hope that it will be useful, but WITHOUT
18 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
19 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
20 * version 2 for more details (a copy is included in the LICENSE file that
21 * accompanied this code).
22 *
23 * You should have received a copy of the GNU General Public License version
24 * 2 along with this work; if not, write to the Free Software Foundation,
25 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
26 *
27 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
28 * or visit www.oracle.com if you need additional information or have any
29 * questions.
30 */
31
32 #include "ti_field.h"
33
34 #include "art_field-inl.h"
35 #include "art_jvmti.h"
36 #include "base/enums.h"
37 #include "dex/dex_file_annotations.h"
38 #include "dex/modifiers.h"
39 #include "jni/jni_internal.h"
40 #include "mirror/object_array-inl.h"
41 #include "scoped_thread_state_change-inl.h"
42 #include "thread-current-inl.h"
43
44 namespace openjdkjvmti {
45
46 // Note: For all these functions, we could do a check that the field actually belongs to the given
47 // class. But the spec seems to assume a certain encoding of the field ID, and so doesn't
48 // specify any errors.
49
GetFieldName(jvmtiEnv * env,jclass klass,jfieldID field,char ** name_ptr,char ** signature_ptr,char ** generic_ptr)50 jvmtiError FieldUtil::GetFieldName(jvmtiEnv* env,
51 jclass klass,
52 jfieldID field,
53 char** name_ptr,
54 char** signature_ptr,
55 char** generic_ptr) {
56 if (klass == nullptr) {
57 return ERR(INVALID_CLASS);
58 }
59 if (field == nullptr) {
60 return ERR(INVALID_FIELDID);
61 }
62
63 art::ScopedObjectAccess soa(art::Thread::Current());
64 art::ArtField* art_field = art::jni::DecodeArtField(field);
65
66 JvmtiUniquePtr<char[]> name_copy;
67 if (name_ptr != nullptr) {
68 const char* field_name = art_field->GetName();
69 if (field_name == nullptr) {
70 field_name = "<error>";
71 }
72 jvmtiError ret;
73 name_copy = CopyString(env, field_name, &ret);
74 if (name_copy == nullptr) {
75 return ret;
76 }
77 *name_ptr = name_copy.get();
78 }
79
80 JvmtiUniquePtr<char[]> signature_copy;
81 if (signature_ptr != nullptr) {
82 const char* sig = art_field->GetTypeDescriptor();
83 jvmtiError ret;
84 signature_copy = CopyString(env, sig, &ret);
85 if (signature_copy == nullptr) {
86 return ret;
87 }
88 *signature_ptr = signature_copy.get();
89 }
90
91 if (generic_ptr != nullptr) {
92 *generic_ptr = nullptr;
93 if (!art_field->GetDeclaringClass()->IsProxyClass()) {
94 art::ObjPtr<art::mirror::ObjectArray<art::mirror::String>> str_array =
95 art::annotations::GetSignatureAnnotationForField(art_field);
96 if (str_array != nullptr) {
97 std::ostringstream oss;
98 for (int32_t i = 0; i != str_array->GetLength(); ++i) {
99 oss << str_array->Get(i)->ToModifiedUtf8();
100 }
101 std::string output_string = oss.str();
102 jvmtiError ret;
103 JvmtiUniquePtr<char[]> copy = CopyString(env, output_string.c_str(), &ret);
104 if (copy == nullptr) {
105 return ret;
106 }
107 *generic_ptr = copy.release();
108 } else if (soa.Self()->IsExceptionPending()) {
109 // TODO: Should we report an error here?
110 soa.Self()->ClearException();
111 }
112 }
113 }
114
115 // Everything is fine, release the buffers.
116 name_copy.release();
117 signature_copy.release();
118
119 return ERR(NONE);
120 }
121
GetFieldDeclaringClass(jvmtiEnv * env ATTRIBUTE_UNUSED,jclass klass,jfieldID field,jclass * declaring_class_ptr)122 jvmtiError FieldUtil::GetFieldDeclaringClass(jvmtiEnv* env ATTRIBUTE_UNUSED,
123 jclass klass,
124 jfieldID field,
125 jclass* declaring_class_ptr) {
126 if (klass == nullptr) {
127 return ERR(INVALID_CLASS);
128 }
129 if (field == nullptr) {
130 return ERR(INVALID_FIELDID);
131 }
132 if (declaring_class_ptr == nullptr) {
133 return ERR(NULL_POINTER);
134 }
135
136 art::ScopedObjectAccess soa(art::Thread::Current());
137 art::ArtField* art_field = art::jni::DecodeArtField(field);
138 art::ObjPtr<art::mirror::Class> field_klass = art_field->GetDeclaringClass();
139
140 *declaring_class_ptr = soa.AddLocalReference<jclass>(field_klass);
141
142 return ERR(NONE);
143 }
144
GetFieldModifiers(jvmtiEnv * env ATTRIBUTE_UNUSED,jclass klass,jfieldID field,jint * modifiers_ptr)145 jvmtiError FieldUtil::GetFieldModifiers(jvmtiEnv* env ATTRIBUTE_UNUSED,
146 jclass klass,
147 jfieldID field,
148 jint* modifiers_ptr) {
149 if (klass == nullptr) {
150 return ERR(INVALID_CLASS);
151 }
152 if (field == nullptr) {
153 return ERR(INVALID_FIELDID);
154 }
155 if (modifiers_ptr == nullptr) {
156 return ERR(NULL_POINTER);
157 }
158
159 art::ScopedObjectAccess soa(art::Thread::Current());
160 art::ArtField* art_field = art::jni::DecodeArtField(field);
161 // Note: Keep this code in sync with Field.getModifiers.
162 uint32_t modifiers = art_field->GetAccessFlags() & 0xFFFF;
163
164 *modifiers_ptr = modifiers;
165 return ERR(NONE);
166 }
167
IsFieldSynthetic(jvmtiEnv * env ATTRIBUTE_UNUSED,jclass klass,jfieldID field,jboolean * is_synthetic_ptr)168 jvmtiError FieldUtil::IsFieldSynthetic(jvmtiEnv* env ATTRIBUTE_UNUSED,
169 jclass klass,
170 jfieldID field,
171 jboolean* is_synthetic_ptr) {
172 if (klass == nullptr) {
173 return ERR(INVALID_CLASS);
174 }
175 if (field == nullptr) {
176 return ERR(INVALID_FIELDID);
177 }
178 if (is_synthetic_ptr == nullptr) {
179 return ERR(NULL_POINTER);
180 }
181
182 art::ScopedObjectAccess soa(art::Thread::Current());
183 art::ArtField* art_field = art::jni::DecodeArtField(field);
184 uint32_t modifiers = art_field->GetAccessFlags();
185
186 *is_synthetic_ptr = ((modifiers & art::kAccSynthetic) != 0) ? JNI_TRUE : JNI_FALSE;
187 return ERR(NONE);
188 }
189
SetFieldModificationWatch(jvmtiEnv * jenv,jclass klass,jfieldID field)190 jvmtiError FieldUtil::SetFieldModificationWatch(jvmtiEnv* jenv, jclass klass, jfieldID field) {
191 ArtJvmTiEnv* env = ArtJvmTiEnv::AsArtJvmTiEnv(jenv);
192 art::WriterMutexLock lk(art::Thread::Current(), env->event_info_mutex_);
193 if (klass == nullptr) {
194 return ERR(INVALID_CLASS);
195 }
196 if (field == nullptr) {
197 return ERR(INVALID_FIELDID);
198 }
199 auto res_pair = env->modify_watched_fields.insert(art::jni::DecodeArtField(field));
200 if (!res_pair.second) {
201 // Didn't get inserted because it's already present!
202 return ERR(DUPLICATE);
203 }
204 return OK;
205 }
206
ClearFieldModificationWatch(jvmtiEnv * jenv,jclass klass,jfieldID field)207 jvmtiError FieldUtil::ClearFieldModificationWatch(jvmtiEnv* jenv, jclass klass, jfieldID field) {
208 ArtJvmTiEnv* env = ArtJvmTiEnv::AsArtJvmTiEnv(jenv);
209 art::WriterMutexLock lk(art::Thread::Current(), env->event_info_mutex_);
210 if (klass == nullptr) {
211 return ERR(INVALID_CLASS);
212 }
213 if (field == nullptr) {
214 return ERR(INVALID_FIELDID);
215 }
216 auto pos = env->modify_watched_fields.find(art::jni::DecodeArtField(field));
217 if (pos == env->modify_watched_fields.end()) {
218 return ERR(NOT_FOUND);
219 }
220 env->modify_watched_fields.erase(pos);
221 return OK;
222 }
223
SetFieldAccessWatch(jvmtiEnv * jenv,jclass klass,jfieldID field)224 jvmtiError FieldUtil::SetFieldAccessWatch(jvmtiEnv* jenv, jclass klass, jfieldID field) {
225 ArtJvmTiEnv* env = ArtJvmTiEnv::AsArtJvmTiEnv(jenv);
226 art::WriterMutexLock lk(art::Thread::Current(), env->event_info_mutex_);
227 if (klass == nullptr) {
228 return ERR(INVALID_CLASS);
229 }
230 if (field == nullptr) {
231 return ERR(INVALID_FIELDID);
232 }
233 auto res_pair = env->access_watched_fields.insert(art::jni::DecodeArtField(field));
234 if (!res_pair.second) {
235 // Didn't get inserted because it's already present!
236 return ERR(DUPLICATE);
237 }
238 return OK;
239 }
240
ClearFieldAccessWatch(jvmtiEnv * jenv,jclass klass,jfieldID field)241 jvmtiError FieldUtil::ClearFieldAccessWatch(jvmtiEnv* jenv, jclass klass, jfieldID field) {
242 ArtJvmTiEnv* env = ArtJvmTiEnv::AsArtJvmTiEnv(jenv);
243 art::WriterMutexLock lk(art::Thread::Current(), env->event_info_mutex_);
244 if (klass == nullptr) {
245 return ERR(INVALID_CLASS);
246 }
247 if (field == nullptr) {
248 return ERR(INVALID_FIELDID);
249 }
250 auto pos = env->access_watched_fields.find(art::jni::DecodeArtField(field));
251 if (pos == env->access_watched_fields.end()) {
252 return ERR(NOT_FOUND);
253 }
254 env->access_watched_fields.erase(pos);
255 return OK;
256 }
257
258 } // namespace openjdkjvmti
259