/* 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
* questions.
*/
#include "ti_class.h"
#include "android-base/stringprintf.h"
#include <mutex>
#include <unordered_set>
#include "art_jvmti.h"
#include "base/macros.h"
#include "class_table-inl.h"
#include "class_linker.h"
#include "common_throws.h"
#include "dex_file_annotations.h"
#include "events-inl.h"
#include "fixed_up_dex_file.h"
#include "gc/heap.h"
#include "gc_root.h"
#include "handle.h"
#include "jni_env_ext-inl.h"
#include "jni_internal.h"
#include "mirror/array-inl.h"
#include "mirror/class-inl.h"
#include "mirror/class_ext.h"
#include "mirror/object_array-inl.h"
#include "mirror/object_reference.h"
#include "mirror/object-inl.h"
#include "mirror/object-refvisitor-inl.h"
#include "mirror/reference.h"
#include "primitive.h"
#include "reflection.h"
#include "runtime.h"
#include "runtime_callbacks.h"
#include "ScopedLocalRef.h"
#include "scoped_thread_state_change-inl.h"
#include "thread-inl.h"
#include "thread_list.h"
#include "ti_class_loader.h"
#include "ti_phase.h"
#include "ti_redefine.h"
#include "utils.h"
#include "well_known_classes.h"
namespace openjdkjvmti {
using android::base::StringPrintf;
static std::unique_ptr<const art::DexFile> MakeSingleDexFile(art::Thread* self,
const char* descriptor,
const std::string& orig_location,
jint final_len,
const unsigned char* final_dex_data)
REQUIRES_SHARED(art::Locks::mutator_lock_) {
// Make the mmap
std::string error_msg;
art::ArraySlice<const unsigned char> final_data(final_dex_data, final_len);
std::unique_ptr<art::MemMap> map(Redefiner::MoveDataToMemMap(orig_location,
final_data,
&error_msg));
if (map.get() == nullptr) {
LOG(WARNING) << "Unable to allocate mmap for redefined dex file! Error was: " << error_msg;
self->ThrowOutOfMemoryError(StringPrintf(
"Unable to allocate dex file for transformation of %s", descriptor).c_str());
return nullptr;
}
// Make a dex-file
if (map->Size() < sizeof(art::DexFile::Header)) {
LOG(WARNING) << "Could not read dex file header because dex_data was too short";
art::ThrowClassFormatError(nullptr,
"Unable to read transformed dex file of %s",
descriptor);
return nullptr;
}
uint32_t checksum = reinterpret_cast<const art::DexFile::Header*>(map->Begin())->checksum_;
std::unique_ptr<const art::DexFile> dex_file(art::DexFile::Open(map->GetName(),
checksum,
std::move(map),
/*verify*/true,
/*verify_checksum*/true,
&error_msg));
if (dex_file.get() == nullptr) {
LOG(WARNING) << "Unable to load modified dex file for " << descriptor << ": " << error_msg;
art::ThrowClassFormatError(nullptr,
"Unable to read transformed dex file of %s because %s",
descriptor,
error_msg.c_str());
return nullptr;
}
if (dex_file->NumClassDefs() != 1) {
LOG(WARNING) << "Dex file contains more than 1 class_def. Ignoring.";
// TODO Throw some other sort of error here maybe?
art::ThrowClassFormatError(
nullptr,
"Unable to use transformed dex file of %s because it contained too many classes",
descriptor);
return nullptr;
}
return dex_file;
}
struct ClassCallback : public art::ClassLoadCallback {
void ClassPreDefine(const char* descriptor,
art::Handle<art::mirror::Class> klass,
art::Handle<art::mirror::ClassLoader> class_loader,
const art::DexFile& initial_dex_file,
const art::DexFile::ClassDef& initial_class_def ATTRIBUTE_UNUSED,
/*out*/art::DexFile const** final_dex_file,
/*out*/art::DexFile::ClassDef const** final_class_def)
OVERRIDE REQUIRES_SHARED(art::Locks::mutator_lock_) {
bool is_enabled =
event_handler->IsEventEnabledAnywhere(ArtJvmtiEvent::kClassFileLoadHookRetransformable) ||
event_handler->IsEventEnabledAnywhere(ArtJvmtiEvent::kClassFileLoadHookNonRetransformable);
if (!is_enabled) {
return;
}
if (descriptor[0] != 'L') {
// It is a primitive or array. Just return
return;
}
jvmtiPhase phase = PhaseUtil::GetPhaseUnchecked();
if (UNLIKELY(phase != JVMTI_PHASE_START && phase != JVMTI_PHASE_LIVE)) {
// We want to wait until we are at least in the START phase so that all WellKnownClasses and
// mirror classes have been initialized and loaded. The runtime relies on these classes having
// specific fields and methods present. Since PreDefine hooks don't need to abide by this
// restriction we will simply not send the event for these classes.
LOG(WARNING) << "Ignoring load of class <" << descriptor << "> as it is being loaded during "
<< "runtime initialization.";
return;
}
// Strip the 'L' and ';' from the descriptor
std::string name(std::string(descriptor).substr(1, strlen(descriptor) - 2));
art::Thread* self = art::Thread::Current();
art::JNIEnvExt* env = self->GetJniEnv();
ScopedLocalRef<jobject> loader(
env, class_loader.IsNull() ? nullptr : env->AddLocalReference<jobject>(class_loader.Get()));
std::unique_ptr<FixedUpDexFile> dex_file_copy(FixedUpDexFile::Create(initial_dex_file));
// Go back to native.
art::ScopedThreadSuspension sts(self, art::ThreadState::kNative);
// Call all Non-retransformable agents.
jint post_no_redefine_len = 0;
unsigned char* post_no_redefine_dex_data = nullptr;
std::unique_ptr<const unsigned char> post_no_redefine_unique_ptr(nullptr);
event_handler->DispatchEvent<ArtJvmtiEvent::kClassFileLoadHookNonRetransformable>(
self,
static_cast<JNIEnv*>(env),
static_cast<jclass>(nullptr), // The class doesn't really exist yet so send null.
loader.get(),
name.c_str(),
static_cast<jobject>(nullptr), // Android doesn't seem to have protection domains
static_cast<jint>(dex_file_copy->Size()),
static_cast<const unsigned char*>(dex_file_copy->Begin()),
static_cast<jint*>(&post_no_redefine_len),
static_cast<unsigned char**>(&post_no_redefine_dex_data));
if (post_no_redefine_dex_data == nullptr) {
DCHECK_EQ(post_no_redefine_len, 0);
post_no_redefine_dex_data = const_cast<unsigned char*>(dex_file_copy->Begin());
post_no_redefine_len = dex_file_copy->Size();
} else {
post_no_redefine_unique_ptr = std::unique_ptr<const unsigned char>(post_no_redefine_dex_data);
DCHECK_GT(post_no_redefine_len, 0);
}
// Call all retransformable agents.
jint final_len = 0;
unsigned char* final_dex_data = nullptr;
std::unique_ptr<const unsigned char> final_dex_unique_ptr(nullptr);
event_handler->DispatchEvent<ArtJvmtiEvent::kClassFileLoadHookRetransformable>(
self,
static_cast<JNIEnv*>(env),
static_cast<jclass>(nullptr), // The class doesn't really exist yet so send null.
loader.get(),
name.c_str(),
static_cast<jobject>(nullptr), // Android doesn't seem to have protection domains
static_cast<jint>(post_no_redefine_len),
static_cast<const unsigned char*>(post_no_redefine_dex_data),
static_cast<jint*>(&final_len),
static_cast<unsigned char**>(&final_dex_data));
if (final_dex_data == nullptr) {
DCHECK_EQ(final_len, 0);
final_dex_data = post_no_redefine_dex_data;
final_len = post_no_redefine_len;
} else {
final_dex_unique_ptr = std::unique_ptr<const unsigned char>(final_dex_data);
DCHECK_GT(final_len, 0);
}
if (final_dex_data != dex_file_copy->Begin()) {
LOG(WARNING) << "Changing class " << descriptor;
art::ScopedObjectAccess soa(self);
art::StackHandleScope<2> hs(self);
// Save the results of all the non-retransformable agents.
// First allocate the ClassExt
art::Handle<art::mirror::ClassExt> ext(hs.NewHandle(klass->EnsureExtDataPresent(self)));
// Make sure we have a ClassExt. This is fine even though we are a temporary since it will
// get copied.
if (ext.IsNull()) {
// We will just return failure if we fail to allocate
LOG(WARNING) << "Could not allocate ext-data for class '" << descriptor << "'. "
<< "Aborting transformation since we will be unable to store it.";
self->AssertPendingOOMException();
return;
}
// Allocate the byte array to store the dex file bytes in.
art::MutableHandle<art::mirror::Object> arr(hs.NewHandle<art::mirror::Object>(nullptr));
if (post_no_redefine_dex_data == dex_file_copy->Begin() && name != "java/lang/Long") {
// we didn't have any non-retransformable agents. We can just cache a pointer to the
// initial_dex_file. It will be kept live by the class_loader.
jlong dex_ptr = reinterpret_cast<uintptr_t>(&initial_dex_file);
art::JValue val;
val.SetJ(dex_ptr);
arr.Assign(art::BoxPrimitive(art::Primitive::kPrimLong, val));
} else {
arr.Assign(art::mirror::ByteArray::AllocateAndFill(
self,
reinterpret_cast<const signed char*>(post_no_redefine_dex_data),
post_no_redefine_len));
}
if (arr.IsNull()) {
LOG(WARNING) << "Unable to allocate memory for initial dex-file. Aborting transformation";
self->AssertPendingOOMException();
return;
}
std::unique_ptr<const art::DexFile> dex_file(MakeSingleDexFile(self,
descriptor,
initial_dex_file.GetLocation(),
final_len,
final_dex_data));
if (dex_file.get() == nullptr) {
return;
}
// TODO Check Redefined dex file for all invariants.
LOG(WARNING) << "Dex file created by class-definition time transformation of "
<< descriptor << " is not checked for all retransformation invariants.";
if (!ClassLoaderHelper::AddToClassLoader(self, class_loader, dex_file.get())) {
LOG(ERROR) << "Unable to add " << descriptor << " to class loader!";
return;
}
// Actually set the ClassExt's original bytes once we have actually succeeded.
ext->SetOriginalDexFile(arr.Get());
// Set the return values
*final_class_def = &dex_file->GetClassDef(0);
*final_dex_file = dex_file.release();
}
}
void ClassLoad(art::Handle<art::mirror::Class> klass) REQUIRES_SHARED(art::Locks::mutator_lock_) {
if (event_handler->IsEventEnabledAnywhere(ArtJvmtiEvent::kClassLoad)) {
art::Thread* thread = art::Thread::Current();
ScopedLocalRef<jclass> jklass(thread->GetJniEnv(),
thread->GetJniEnv()->AddLocalReference<jclass>(klass.Get()));
ScopedLocalRef<jthread> thread_jni(
thread->GetJniEnv(), thread->GetJniEnv()->AddLocalReference<jthread>(thread->GetPeer()));
{
art::ScopedThreadSuspension sts(thread, art::ThreadState::kNative);
event_handler->DispatchEvent<ArtJvmtiEvent::kClassLoad>(
thread,
static_cast<JNIEnv*>(thread->GetJniEnv()),
thread_jni.get(),
jklass.get());
}
if (klass->IsTemp()) {
AddTempClass(thread, jklass.get());
}
}
}
void ClassPrepare(art::Handle<art::mirror::Class> temp_klass,
art::Handle<art::mirror::Class> klass)
REQUIRES_SHARED(art::Locks::mutator_lock_) {
if (event_handler->IsEventEnabledAnywhere(ArtJvmtiEvent::kClassPrepare)) {
art::Thread* thread = art::Thread::Current();
if (temp_klass.Get() != klass.Get()) {
DCHECK(temp_klass->IsTemp());
DCHECK(temp_klass->IsRetired());
HandleTempClass(thread, temp_klass, klass);
}
ScopedLocalRef<jclass> jklass(thread->GetJniEnv(),
thread->GetJniEnv()->AddLocalReference<jclass>(klass.Get()));
ScopedLocalRef<jthread> thread_jni(
thread->GetJniEnv(), thread->GetJniEnv()->AddLocalReference<jthread>(thread->GetPeer()));
art::ScopedThreadSuspension sts(thread, art::ThreadState::kNative);
event_handler->DispatchEvent<ArtJvmtiEvent::kClassPrepare>(
thread,
static_cast<JNIEnv*>(thread->GetJniEnv()),
thread_jni.get(),
jklass.get());
}
}
// To support parallel class-loading, we need to perform some locking dances here. Namely,
// the fixup stage must not be holding the temp_classes lock when it fixes up the system
// (as that requires suspending all mutators).
void AddTempClass(art::Thread* self, jclass klass) {
std::unique_lock<std::mutex> mu(temp_classes_lock);
jclass global_klass = reinterpret_cast<jclass>(self->GetJniEnv()->NewGlobalRef(klass));
temp_classes.push_back(global_klass);
}
void HandleTempClass(art::Thread* self,
art::Handle<art::mirror::Class> temp_klass,
art::Handle<art::mirror::Class> klass)
REQUIRES_SHARED(art::Locks::mutator_lock_) {
bool requires_fixup = false;
{
std::unique_lock<std::mutex> mu(temp_classes_lock);
if (temp_classes.empty()) {
return;
}
for (auto it = temp_classes.begin(); it != temp_classes.end(); ++it) {
if (temp_klass.Get() == art::ObjPtr<art::mirror::Class>::DownCast(self->DecodeJObject(*it))) {
self->GetJniEnv()->DeleteGlobalRef(*it);
temp_classes.erase(it);
requires_fixup = true;
break;
}
}
}
if (requires_fixup) {
FixupTempClass(self, temp_klass, klass);
}
}
void FixupTempClass(art::Thread* self,
art::Handle<art::mirror::Class> temp_klass,
art::Handle<art::mirror::Class> klass)
REQUIRES_SHARED(art::Locks::mutator_lock_) {
// Suspend everything.
art::gc::Heap* heap = art::Runtime::Current()->GetHeap();
if (heap->IsGcConcurrentAndMoving()) {
// Need to take a heap dump while GC isn't running. See the
// comment in Heap::VisitObjects().
heap->IncrementDisableMovingGC(self);
}
{
art::ScopedThreadSuspension sts(self, art::kWaitingForVisitObjects);
art::ScopedSuspendAll ssa("FixupTempClass");
art::mirror::Class* input = temp_klass.Get();
art::mirror::Class* output = klass.Get();
FixupGlobalReferenceTables(input, output);
FixupLocalReferenceTables(self, input, output);
FixupHeap(input, output);
}
if (heap->IsGcConcurrentAndMoving()) {
heap->DecrementDisableMovingGC(self);
}
}
class RootUpdater : public art::RootVisitor {
public:
RootUpdater(const art::mirror::Class* input, art::mirror::Class* output)
: input_(input), output_(output) {}
void VisitRoots(art::mirror::Object*** roots,
size_t count,
const art::RootInfo& info ATTRIBUTE_UNUSED)
OVERRIDE {
for (size_t i = 0; i != count; ++i) {
if (*roots[i] == input_) {
*roots[i] = output_;
}
}
}
void VisitRoots(art::mirror::CompressedReference<art::mirror::Object>** roots,
size_t count,
const art::RootInfo& info ATTRIBUTE_UNUSED)
OVERRIDE REQUIRES_SHARED(art::Locks::mutator_lock_) {
for (size_t i = 0; i != count; ++i) {
if (roots[i]->AsMirrorPtr() == input_) {
roots[i]->Assign(output_);
}
}
}
private:
const art::mirror::Class* input_;
art::mirror::Class* output_;
};
void FixupGlobalReferenceTables(art::mirror::Class* input, art::mirror::Class* output)
REQUIRES(art::Locks::mutator_lock_) {
art::JavaVMExt* java_vm = art::Runtime::Current()->GetJavaVM();
// Fix up the global table with a root visitor.
RootUpdater global_update(input, output);
java_vm->VisitRoots(&global_update);
class WeakGlobalUpdate : public art::IsMarkedVisitor {
public:
WeakGlobalUpdate(art::mirror::Class* root_input, art::mirror::Class* root_output)
: input_(root_input), output_(root_output) {}
art::mirror::Object* IsMarked(art::mirror::Object* obj) OVERRIDE {
if (obj == input_) {
return output_;
}
return obj;
}
private:
const art::mirror::Class* input_;
art::mirror::Class* output_;
};
WeakGlobalUpdate weak_global_update(input, output);
java_vm->SweepJniWeakGlobals(&weak_global_update);
}
void FixupLocalReferenceTables(art::Thread* self,
art::mirror::Class* input,
art::mirror::Class* output)
REQUIRES(art::Locks::mutator_lock_) {
class LocalUpdate {
public:
LocalUpdate(const art::mirror::Class* root_input, art::mirror::Class* root_output)
: input_(root_input), output_(root_output) {}
static void Callback(art::Thread* t, void* arg) REQUIRES(art::Locks::mutator_lock_) {
LocalUpdate* local = reinterpret_cast<LocalUpdate*>(arg);
// Fix up the local table with a root visitor.
RootUpdater local_update(local->input_, local->output_);
t->GetJniEnv()->locals.VisitRoots(
&local_update, art::RootInfo(art::kRootJNILocal, t->GetThreadId()));
}
private:
const art::mirror::Class* input_;
art::mirror::Class* output_;
};
LocalUpdate local_upd(input, output);
art::MutexLock mu(self, *art::Locks::thread_list_lock_);
art::Runtime::Current()->GetThreadList()->ForEach(LocalUpdate::Callback, &local_upd);
}
void FixupHeap(art::mirror::Class* input, art::mirror::Class* output)
REQUIRES(art::Locks::mutator_lock_) {
class HeapFixupVisitor {
public:
HeapFixupVisitor(const art::mirror::Class* root_input, art::mirror::Class* root_output)
: input_(root_input), output_(root_output) {}
void operator()(art::mirror::Object* src,
art::MemberOffset field_offset,
bool is_static ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(art::Locks::mutator_lock_) {
art::mirror::HeapReference<art::mirror::Object>* trg =
src->GetFieldObjectReferenceAddr(field_offset);
if (trg->AsMirrorPtr() == input_) {
DCHECK_NE(field_offset.Uint32Value(), 0u); // This shouldn't be the class field of
// an object.
trg->Assign(output_);
}
}
void operator()(art::ObjPtr<art::mirror::Class> klass ATTRIBUTE_UNUSED,
art::ObjPtr<art::mirror::Reference> reference) const
REQUIRES_SHARED(art::Locks::mutator_lock_) {
art::mirror::Object* val = reference->GetReferent();
if (val == input_) {
reference->SetReferent<false>(output_);
}
}
void VisitRoot(art::mirror::CompressedReference<art::mirror::Object>* root ATTRIBUTE_UNUSED)
const {
LOG(FATAL) << "Unreachable";
}
void VisitRootIfNonNull(
art::mirror::CompressedReference<art::mirror::Object>* root ATTRIBUTE_UNUSED) const {
LOG(FATAL) << "Unreachable";
}
static void AllObjectsCallback(art::mirror::Object* obj, void* arg)
REQUIRES_SHARED(art::Locks::mutator_lock_) {
HeapFixupVisitor* hfv = reinterpret_cast<HeapFixupVisitor*>(arg);
// Visit references, not native roots.
obj->VisitReferences<false>(*hfv, *hfv);
}
private:
const art::mirror::Class* input_;
art::mirror::Class* output_;
};
HeapFixupVisitor hfv(input, output);
art::Runtime::Current()->GetHeap()->VisitObjectsPaused(HeapFixupVisitor::AllObjectsCallback,
&hfv);
}
// A set of all the temp classes we have handed out. We have to fix up references to these.
// For simplicity, we store the temp classes as JNI global references in a vector. Normally a
// Prepare event will closely follow, so the vector should be small.
std::mutex temp_classes_lock;
std::vector<jclass> temp_classes;
EventHandler* event_handler = nullptr;
};
ClassCallback gClassCallback;
void ClassUtil::Register(EventHandler* handler) {
gClassCallback.event_handler = handler;
art::ScopedThreadStateChange stsc(art::Thread::Current(),
art::ThreadState::kWaitingForDebuggerToAttach);
art::ScopedSuspendAll ssa("Add load callback");
art::Runtime::Current()->GetRuntimeCallbacks()->AddClassLoadCallback(&gClassCallback);
}
void ClassUtil::Unregister() {
art::ScopedThreadStateChange stsc(art::Thread::Current(),
art::ThreadState::kWaitingForDebuggerToAttach);
art::ScopedSuspendAll ssa("Remove thread callback");
art::Runtime* runtime = art::Runtime::Current();
runtime->GetRuntimeCallbacks()->RemoveClassLoadCallback(&gClassCallback);
}
jvmtiError ClassUtil::GetClassFields(jvmtiEnv* env,
jclass jklass,
jint* field_count_ptr,
jfieldID** fields_ptr) {
art::ScopedObjectAccess soa(art::Thread::Current());
art::ObjPtr<art::mirror::Class> klass = soa.Decode<art::mirror::Class>(jklass);
if (klass == nullptr) {
return ERR(INVALID_CLASS);
}
if (field_count_ptr == nullptr || fields_ptr == nullptr) {
return ERR(NULL_POINTER);
}
art::IterationRange<art::StrideIterator<art::ArtField>> ifields = klass->GetIFields();
art::IterationRange<art::StrideIterator<art::ArtField>> sfields = klass->GetSFields();
size_t array_size = klass->NumInstanceFields() + klass->NumStaticFields();
unsigned char* out_ptr;
jvmtiError allocError = env->Allocate(array_size * sizeof(jfieldID), &out_ptr);
if (allocError != ERR(NONE)) {
return allocError;
}
jfieldID* field_array = reinterpret_cast<jfieldID*>(out_ptr);
size_t array_idx = 0;
for (art::ArtField& field : sfields) {
field_array[array_idx] = art::jni::EncodeArtField(&field);
++array_idx;
}
for (art::ArtField& field : ifields) {
field_array[array_idx] = art::jni::EncodeArtField(&field);
++array_idx;
}
*field_count_ptr = static_cast<jint>(array_size);
*fields_ptr = field_array;
return ERR(NONE);
}
jvmtiError ClassUtil::GetClassMethods(jvmtiEnv* env,
jclass jklass,
jint* method_count_ptr,
jmethodID** methods_ptr) {
art::ScopedObjectAccess soa(art::Thread::Current());
art::ObjPtr<art::mirror::Class> klass = soa.Decode<art::mirror::Class>(jklass);
if (klass == nullptr) {
return ERR(INVALID_CLASS);
}
if (method_count_ptr == nullptr || methods_ptr == nullptr) {
return ERR(NULL_POINTER);
}
size_t array_size = klass->NumDeclaredVirtualMethods() + klass->NumDirectMethods();
unsigned char* out_ptr;
jvmtiError allocError = env->Allocate(array_size * sizeof(jmethodID), &out_ptr);
if (allocError != ERR(NONE)) {
return allocError;
}
jmethodID* method_array = reinterpret_cast<jmethodID*>(out_ptr);
if (art::kIsDebugBuild) {
size_t count = 0;
for (auto& m ATTRIBUTE_UNUSED : klass->GetDeclaredMethods(art::kRuntimePointerSize)) {
count++;
}
CHECK_EQ(count, klass->NumDirectMethods() + klass->NumDeclaredVirtualMethods());
}
size_t array_idx = 0;
for (auto& m : klass->GetDeclaredMethods(art::kRuntimePointerSize)) {
method_array[array_idx] = art::jni::EncodeArtMethod(&m);
++array_idx;
}
*method_count_ptr = static_cast<jint>(array_size);
*methods_ptr = method_array;
return ERR(NONE);
}
jvmtiError ClassUtil::GetImplementedInterfaces(jvmtiEnv* env,
jclass jklass,
jint* interface_count_ptr,
jclass** interfaces_ptr) {
art::ScopedObjectAccess soa(art::Thread::Current());
art::ObjPtr<art::mirror::Class> klass = soa.Decode<art::mirror::Class>(jklass);
if (klass == nullptr) {
return ERR(INVALID_CLASS);
}
if (interface_count_ptr == nullptr || interfaces_ptr == nullptr) {
return ERR(NULL_POINTER);
}
// Need to handle array specifically. Arrays implement Serializable and Cloneable, but the
// spec says these should not be reported.
if (klass->IsArrayClass()) {
*interface_count_ptr = 0;
*interfaces_ptr = nullptr; // TODO: Should we allocate a dummy here?
return ERR(NONE);
}
size_t array_size = klass->NumDirectInterfaces();
unsigned char* out_ptr;
jvmtiError allocError = env->Allocate(array_size * sizeof(jclass), &out_ptr);
if (allocError != ERR(NONE)) {
return allocError;
}
jclass* interface_array = reinterpret_cast<jclass*>(out_ptr);
art::StackHandleScope<1> hs(soa.Self());
art::Handle<art::mirror::Class> h_klass(hs.NewHandle(klass));
for (uint32_t idx = 0; idx != array_size; ++idx) {
art::ObjPtr<art::mirror::Class> inf_klass =
art::mirror::Class::ResolveDirectInterface(soa.Self(), h_klass, idx);
if (inf_klass == nullptr) {
soa.Self()->ClearException();
env->Deallocate(out_ptr);
// TODO: What is the right error code here?
return ERR(INTERNAL);
}
interface_array[idx] = soa.AddLocalReference<jclass>(inf_klass);
}
*interface_count_ptr = static_cast<jint>(array_size);
*interfaces_ptr = interface_array;
return ERR(NONE);
}
jvmtiError ClassUtil::GetClassSignature(jvmtiEnv* env,
jclass jklass,
char** signature_ptr,
char** generic_ptr) {
art::ScopedObjectAccess soa(art::Thread::Current());
art::ObjPtr<art::mirror::Class> klass = soa.Decode<art::mirror::Class>(jklass);
if (klass == nullptr) {
return ERR(INVALID_CLASS);
}
JvmtiUniquePtr<char[]> sig_copy;
if (signature_ptr != nullptr) {
std::string storage;
const char* descriptor = klass->GetDescriptor(&storage);
jvmtiError ret;
sig_copy = CopyString(env, descriptor, &ret);
if (sig_copy == nullptr) {
return ret;
}
*signature_ptr = sig_copy.get();
}
if (generic_ptr != nullptr) {
*generic_ptr = nullptr;
if (!klass->IsProxyClass() && klass->GetDexCache() != nullptr) {
art::StackHandleScope<1> hs(soa.Self());
art::Handle<art::mirror::Class> h_klass = hs.NewHandle(klass);
art::mirror::ObjectArray<art::mirror::String>* str_array =
art::annotations::GetSignatureAnnotationForClass(h_klass);
if (str_array != nullptr) {
std::ostringstream oss;
for (int32_t i = 0; i != str_array->GetLength(); ++i) {
oss << str_array->Get(i)->ToModifiedUtf8();
}
std::string output_string = oss.str();
jvmtiError ret;
JvmtiUniquePtr<char[]> copy = CopyString(env, output_string.c_str(), &ret);
if (copy == nullptr) {
return ret;
}
*generic_ptr = copy.release();
} else if (soa.Self()->IsExceptionPending()) {
// TODO: Should we report an error here?
soa.Self()->ClearException();
}
}
}
// Everything is fine, release the buffers.
sig_copy.release();
return ERR(NONE);
}
jvmtiError ClassUtil::GetClassStatus(jvmtiEnv* env ATTRIBUTE_UNUSED,
jclass jklass,
jint* status_ptr) {
art::ScopedObjectAccess soa(art::Thread::Current());
art::ObjPtr<art::mirror::Class> klass = soa.Decode<art::mirror::Class>(jklass);
if (klass == nullptr) {
return ERR(INVALID_CLASS);
}
if (status_ptr == nullptr) {
return ERR(NULL_POINTER);
}
if (klass->IsArrayClass()) {
*status_ptr = JVMTI_CLASS_STATUS_ARRAY;
} else if (klass->IsPrimitive()) {
*status_ptr = JVMTI_CLASS_STATUS_PRIMITIVE;
} else {
*status_ptr = JVMTI_CLASS_STATUS_VERIFIED; // All loaded classes are structurally verified.
// This is finicky. If there's an error, we'll say it wasn't prepared.
if (klass->IsResolved()) {
*status_ptr |= JVMTI_CLASS_STATUS_PREPARED;
}
if (klass->IsInitialized()) {
*status_ptr |= JVMTI_CLASS_STATUS_INITIALIZED;
}
// Technically the class may be erroneous for other reasons, but we do not have enough info.
if (klass->IsErroneous()) {
*status_ptr |= JVMTI_CLASS_STATUS_ERROR;
}
}
return ERR(NONE);
}
template <typename T>
static jvmtiError ClassIsT(jclass jklass, T test, jboolean* is_t_ptr) {
art::ScopedObjectAccess soa(art::Thread::Current());
art::ObjPtr<art::mirror::Class> klass = soa.Decode<art::mirror::Class>(jklass);
if (klass == nullptr) {
return ERR(INVALID_CLASS);
}
if (is_t_ptr == nullptr) {
return ERR(NULL_POINTER);
}
*is_t_ptr = test(klass) ? JNI_TRUE : JNI_FALSE;
return ERR(NONE);
}
jvmtiError ClassUtil::IsInterface(jvmtiEnv* env ATTRIBUTE_UNUSED,
jclass jklass,
jboolean* is_interface_ptr) {
auto test = [](art::ObjPtr<art::mirror::Class> klass) REQUIRES_SHARED(art::Locks::mutator_lock_) {
return klass->IsInterface();
};
return ClassIsT(jklass, test, is_interface_ptr);
}
jvmtiError ClassUtil::IsArrayClass(jvmtiEnv* env ATTRIBUTE_UNUSED,
jclass jklass,
jboolean* is_array_class_ptr) {
auto test = [](art::ObjPtr<art::mirror::Class> klass) REQUIRES_SHARED(art::Locks::mutator_lock_) {
return klass->IsArrayClass();
};
return ClassIsT(jklass, test, is_array_class_ptr);
}
// Keep this in sync with Class.getModifiers().
static uint32_t ClassGetModifiers(art::Thread* self, art::ObjPtr<art::mirror::Class> klass)
REQUIRES_SHARED(art::Locks::mutator_lock_) {
if (klass->IsArrayClass()) {
uint32_t component_modifiers = ClassGetModifiers(self, klass->GetComponentType());
if ((component_modifiers & art::kAccInterface) != 0) {
component_modifiers &= ~(art::kAccInterface | art::kAccStatic);
}
return art::kAccAbstract | art::kAccFinal | component_modifiers;
}
uint32_t modifiers = klass->GetAccessFlags() & art::kAccJavaFlagsMask;
art::StackHandleScope<1> hs(self);
art::Handle<art::mirror::Class> h_klass(hs.NewHandle(klass));
return art::mirror::Class::GetInnerClassFlags(h_klass, modifiers);
}
jvmtiError ClassUtil::GetClassModifiers(jvmtiEnv* env ATTRIBUTE_UNUSED,
jclass jklass,
jint* modifiers_ptr) {
art::ScopedObjectAccess soa(art::Thread::Current());
art::ObjPtr<art::mirror::Class> klass = soa.Decode<art::mirror::Class>(jklass);
if (klass == nullptr) {
return ERR(INVALID_CLASS);
}
if (modifiers_ptr == nullptr) {
return ERR(NULL_POINTER);
}
*modifiers_ptr = ClassGetModifiers(soa.Self(), klass);
return ERR(NONE);
}
jvmtiError ClassUtil::GetClassLoader(jvmtiEnv* env ATTRIBUTE_UNUSED,
jclass jklass,
jobject* classloader_ptr) {
art::ScopedObjectAccess soa(art::Thread::Current());
art::ObjPtr<art::mirror::Class> klass = soa.Decode<art::mirror::Class>(jklass);
if (klass == nullptr) {
return ERR(INVALID_CLASS);
}
if (classloader_ptr == nullptr) {
return ERR(NULL_POINTER);
}
*classloader_ptr = soa.AddLocalReference<jobject>(klass->GetClassLoader());
return ERR(NONE);
}
jvmtiError ClassUtil::GetClassLoaderClasses(jvmtiEnv* env,
jobject initiating_loader,
jint* class_count_ptr,
jclass** classes_ptr) {
UNUSED(env, initiating_loader, class_count_ptr, classes_ptr);
if (class_count_ptr == nullptr || classes_ptr == nullptr) {
return ERR(NULL_POINTER);
}
art::Thread* self = art::Thread::Current();
if (!self->GetJniEnv()->IsInstanceOf(initiating_loader,
art::WellKnownClasses::java_lang_ClassLoader)) {
return ERR(ILLEGAL_ARGUMENT);
}
if (self->GetJniEnv()->IsInstanceOf(initiating_loader,
art::WellKnownClasses::java_lang_BootClassLoader)) {
// Need to use null for the BootClassLoader.
initiating_loader = nullptr;
}
art::ScopedObjectAccess soa(self);
art::ObjPtr<art::mirror::ClassLoader> class_loader =
soa.Decode<art::mirror::ClassLoader>(initiating_loader);
art::ClassLinker* class_linker = art::Runtime::Current()->GetClassLinker();
art::ReaderMutexLock mu(self, *art::Locks::classlinker_classes_lock_);
art::ClassTable* class_table = class_linker->ClassTableForClassLoader(class_loader);
if (class_table == nullptr) {
// Nothing loaded.
*class_count_ptr = 0;
*classes_ptr = nullptr;
return ERR(NONE);
}
struct ClassTableCount {
bool operator()(art::ObjPtr<art::mirror::Class> klass) {
DCHECK(klass != nullptr);
++count;
return true;
}
size_t count = 0;
};
ClassTableCount ctc;
class_table->Visit(ctc);
if (ctc.count == 0) {
// Nothing loaded.
*class_count_ptr = 0;
*classes_ptr = nullptr;
return ERR(NONE);
}
unsigned char* data;
jvmtiError data_result = env->Allocate(ctc.count * sizeof(jclass), &data);
if (data_result != ERR(NONE)) {
return data_result;
}
jclass* class_array = reinterpret_cast<jclass*>(data);
struct ClassTableFill {
bool operator()(art::ObjPtr<art::mirror::Class> klass)
REQUIRES_SHARED(art::Locks::mutator_lock_) {
DCHECK(klass != nullptr);
DCHECK_LT(count, ctc_ref.count);
local_class_array[count++] = soa_ptr->AddLocalReference<jclass>(klass);
return true;
}
jclass* local_class_array;
const ClassTableCount& ctc_ref;
art::ScopedObjectAccess* soa_ptr;
size_t count;
};
ClassTableFill ctf = { class_array, ctc, &soa, 0 };
class_table->Visit(ctf);
DCHECK_EQ(ctc.count, ctf.count);
*class_count_ptr = ctc.count;
*classes_ptr = class_array;
return ERR(NONE);
}
jvmtiError ClassUtil::GetClassVersionNumbers(jvmtiEnv* env ATTRIBUTE_UNUSED,
jclass jklass,
jint* minor_version_ptr,
jint* major_version_ptr) {
art::ScopedObjectAccess soa(art::Thread::Current());
if (jklass == nullptr) {
return ERR(INVALID_CLASS);
}
art::ObjPtr<art::mirror::Object> jklass_obj = soa.Decode<art::mirror::Object>(jklass);
if (!jklass_obj->IsClass()) {
return ERR(INVALID_CLASS);
}
art::ObjPtr<art::mirror::Class> klass = jklass_obj->AsClass();
if (klass->IsPrimitive() || klass->IsArrayClass()) {
return ERR(INVALID_CLASS);
}
if (minor_version_ptr == nullptr || major_version_ptr == nullptr) {
return ERR(NULL_POINTER);
}
// Note: proxies will show the dex file version of java.lang.reflect.Proxy, as that is
// what their dex cache copies from.
uint32_t version = klass->GetDexFile().GetHeader().GetVersion();
*major_version_ptr = static_cast<jint>(version);
*minor_version_ptr = 0;
return ERR(NONE);
}
} // namespace openjdkjvmti