/* Copyright (C) 2016 The Android Open Source Project
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This file implements interfaces from the file jvmti.h. This implementation
* is licensed under the same terms as the file jvmti.h. The
* copyright and license information for the file jvmti.h follows.
*
* Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
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*/
#include "ti_class_definition.h"
#include "base/array_slice.h"
#include "class_linker-inl.h"
#include "dex_file.h"
#include "fixed_up_dex_file.h"
#include "handle_scope-inl.h"
#include "handle.h"
#include "mirror/class_ext.h"
#include "mirror/class-inl.h"
#include "mirror/object-inl.h"
#include "reflection.h"
#include "thread.h"
namespace openjdkjvmti {
bool ArtClassDefinition::IsModified() const {
// RedefineClasses calls always are 'modified' since they need to change the original_dex_file of
// the class.
if (redefined_) {
return true;
}
// Check if the dex file we want to set is the same as the current one.
// Unfortunately we need to do this check even if no modifications have been done since it could
// be that agents were removed in the mean-time so we still have a different dex file. The dex
// checksum means this is likely to be fairly fast.
return static_cast<jint>(original_dex_file_.size()) != dex_len_ ||
memcmp(&original_dex_file_.At(0), dex_data_.get(), dex_len_) != 0;
}
jvmtiError ArtClassDefinition::InitCommon(ArtJvmTiEnv* env, jclass klass) {
JNIEnv* jni_env = GetJniEnv(env);
if (jni_env == nullptr) {
return ERR(INTERNAL);
}
art::ScopedObjectAccess soa(jni_env);
art::ObjPtr<art::mirror::Class> m_klass(soa.Decode<art::mirror::Class>(klass));
if (m_klass.IsNull()) {
return ERR(INVALID_CLASS);
}
klass_ = klass;
loader_ = soa.AddLocalReference<jobject>(m_klass->GetClassLoader());
std::string descriptor_store;
std::string descriptor(m_klass->GetDescriptor(&descriptor_store));
name_ = descriptor.substr(1, descriptor.size() - 2);
// Android doesn't really have protection domains.
protection_domain_ = nullptr;
return OK;
}
// Gets the data surrounding the given class.
static jvmtiError GetDexDataForRetransformation(ArtJvmTiEnv* env,
art::Handle<art::mirror::Class> klass,
/*out*/jint* dex_data_len,
/*out*/unsigned char** dex_data)
REQUIRES_SHARED(art::Locks::mutator_lock_) {
art::StackHandleScope<3> hs(art::Thread::Current());
art::Handle<art::mirror::ClassExt> ext(hs.NewHandle(klass->GetExtData()));
const art::DexFile* dex_file = nullptr;
if (!ext.IsNull()) {
art::Handle<art::mirror::Object> orig_dex(hs.NewHandle(ext->GetOriginalDexFile()));
if (!orig_dex.IsNull()) {
if (orig_dex->IsArrayInstance()) {
DCHECK(orig_dex->GetClass()->GetComponentType()->IsPrimitiveByte());
art::Handle<art::mirror::ByteArray> orig_dex_bytes(
hs.NewHandle(art::down_cast<art::mirror::ByteArray*>(orig_dex->AsArray())));
*dex_data_len = static_cast<jint>(orig_dex_bytes->GetLength());
return CopyDataIntoJvmtiBuffer(
env,
reinterpret_cast<const unsigned char*>(orig_dex_bytes->GetData()),
*dex_data_len,
/*out*/dex_data);
} else if (orig_dex->IsDexCache()) {
dex_file = orig_dex->AsDexCache()->GetDexFile();
} else {
DCHECK(orig_dex->GetClass()->DescriptorEquals("Ljava/lang/Long;"))
<< "Expected java/lang/Long but found object of type "
<< orig_dex->GetClass()->PrettyClass();
art::ObjPtr<art::mirror::Class> prim_long_class(
art::Runtime::Current()->GetClassLinker()->GetClassRoot(
art::ClassLinker::kPrimitiveLong));
art::JValue val;
if (!art::UnboxPrimitiveForResult(orig_dex.Get(), prim_long_class, &val)) {
// This should never happen.
return ERR(INTERNAL);
}
dex_file = reinterpret_cast<const art::DexFile*>(static_cast<uintptr_t>(val.GetJ()));
}
}
}
if (dex_file == nullptr) {
dex_file = &klass->GetDexFile();
}
std::unique_ptr<FixedUpDexFile> fixed_dex_file(FixedUpDexFile::Create(*dex_file));
*dex_data_len = static_cast<jint>(fixed_dex_file->Size());
return CopyDataIntoJvmtiBuffer(env,
fixed_dex_file->Begin(),
fixed_dex_file->Size(),
/*out*/dex_data);
}
jvmtiError ArtClassDefinition::Init(ArtJvmTiEnv* env, jclass klass) {
jvmtiError res = InitCommon(env, klass);
if (res != OK) {
return res;
}
unsigned char* new_data = nullptr;
art::Thread* self = art::Thread::Current();
art::ScopedObjectAccess soa(self);
art::StackHandleScope<1> hs(self);
art::Handle<art::mirror::Class> m_klass(hs.NewHandle(self->DecodeJObject(klass)->AsClass()));
res = GetDexDataForRetransformation(env, m_klass, &dex_len_, &new_data);
if (res != OK) {
return res;
}
dex_data_ = MakeJvmtiUniquePtr(env, new_data);
if (m_klass->GetExtData() == nullptr || m_klass->GetExtData()->GetOriginalDexFile() == nullptr) {
// We have never redefined class this yet. Keep track of what the (de-quickened) dex file looks
// like so we can tell if anything has changed. Really we would like to just always do the
// 'else' block but the fact that we de-quickened stuff screws us over.
unsigned char* original_data_memory = nullptr;
res = CopyDataIntoJvmtiBuffer(env, dex_data_.get(), dex_len_, &original_data_memory);
original_dex_file_memory_ = MakeJvmtiUniquePtr(env, original_data_memory);
original_dex_file_ = art::ArraySlice<const unsigned char>(original_data_memory, dex_len_);
} else {
// We know that we have been redefined at least once (there is an original_dex_file set in
// the class) so we can just use the current dex file directly.
const art::DexFile& dex_file = m_klass->GetDexFile();
original_dex_file_ = art::ArraySlice<const unsigned char>(dex_file.Begin(), dex_file.Size());
}
return res;
}
jvmtiError ArtClassDefinition::Init(ArtJvmTiEnv* env, const jvmtiClassDefinition& def) {
jvmtiError res = InitCommon(env, def.klass);
if (res != OK) {
return res;
}
unsigned char* new_data = nullptr;
original_dex_file_ = art::ArraySlice<const unsigned char>(def.class_bytes, def.class_byte_count);
redefined_ = true;
dex_len_ = def.class_byte_count;
res = CopyDataIntoJvmtiBuffer(env, def.class_bytes, def.class_byte_count, /*out*/ &new_data);
dex_data_ = MakeJvmtiUniquePtr(env, new_data);
return res;
}
} // namespace openjdkjvmti