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Diffstat (limited to 'openjdkjvmti/ti_class.cc')
| -rw-r--r-- | openjdkjvmti/ti_class.cc | 1086 |
1 files changed, 1086 insertions, 0 deletions
diff --git a/openjdkjvmti/ti_class.cc b/openjdkjvmti/ti_class.cc new file mode 100644 index 0000000000..954b5d1d03 --- /dev/null +++ b/openjdkjvmti/ti_class.cc @@ -0,0 +1,1086 @@ +/* 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/array_ref.h" +#include "base/macros.h" +#include "class_linker.h" +#include "class_table-inl.h" +#include "common_throws.h" +#include "dex_file_annotations.h" +#include "events-inl.h" +#include "fixed_up_dex_file.h" +#include "gc/heap-visit-objects-inl.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-inl.h" +#include "mirror/object-refvisitor-inl.h" +#include "mirror/object_array-inl.h" +#include "mirror/object_reference.h" +#include "mirror/reference.h" +#include "nativehelper/ScopedLocalRef.h" +#include "primitive.h" +#include "reflection.h" +#include "runtime.h" +#include "runtime_callbacks.h" +#include "scoped_thread_state_change-inl.h" +#include "thread-current-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::ArrayRef<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::string map_name = map->GetName(); + std::unique_ptr<const art::DexFile> dex_file(art::DexFile::Open(map_name, + 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; +} + +// A deleter that acts like the jvmtiEnv->Deallocate so that asan does not get tripped up. +// TODO We should everything use the actual jvmtiEnv->Allocate/Deallocate functions once we can +// figure out which env to use. +template <typename T> +class FakeJvmtiDeleter { + public: + FakeJvmtiDeleter() {} + + FakeJvmtiDeleter(FakeJvmtiDeleter&) = default; + FakeJvmtiDeleter(FakeJvmtiDeleter&&) = default; + FakeJvmtiDeleter& operator=(const FakeJvmtiDeleter&) = default; + + template <typename U> void operator()(const U* ptr) const { + if (ptr != nullptr) { + free(const_cast<U*>(ptr)); + } + } +}; + +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, FakeJvmtiDeleter<const unsigned char>> + post_no_redefine_unique_ptr(nullptr, FakeJvmtiDeleter<const unsigned char>()); + 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, FakeJvmtiDeleter<const unsigned char>>( + post_no_redefine_dex_data, FakeJvmtiDeleter<const unsigned char>()); + 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, FakeJvmtiDeleter<const unsigned char>> + final_dex_unique_ptr(nullptr, FakeJvmtiDeleter<const unsigned char>()); + 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, FakeJvmtiDeleter<const unsigned char>>( + final_dex_data, FakeJvmtiDeleter<const unsigned char>()); + 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())); + art::ObjPtr<art::mirror::Object> peer(thread->GetPeer()); + ScopedLocalRef<jthread> thread_jni( + thread->GetJniEnv(), + peer.IsNull() ? nullptr : thread->GetJniEnv()->AddLocalReference<jthread>(peer)); + { + 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())); + art::ObjPtr<art::mirror::Object> peer(thread->GetPeer()); + ScopedLocalRef<jthread> thread_jni( + thread->GetJniEnv(), + peer.IsNull() ? nullptr : thread->GetJniEnv()->AddLocalReference<jthread>(peer)); + 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"; + } + + private: + const art::mirror::Class* input_; + art::mirror::Class* output_; + }; + HeapFixupVisitor hfv(input, output); + auto object_visitor = [&](art::mirror::Object* obj) { + obj->VisitReferences<false>(hfv, hfv); // Visit references, not native roots. + }; + art::Runtime::Current()->GetHeap()->VisitObjectsPaused(object_visitor); + } + + // 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); + } + + // Check if this class is a temporary class object used for loading. Since we are seeing it the + // class must not have been prepared yet since otherwise the fixup would have gotten the jobject + // to point to the final class object. + if (klass->IsTemp() || klass->IsRetired()) { + return ERR(CLASS_NOT_PREPARED); + } + + 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); + } + + // Check if this class is a temporary class object used for loading. Since we are seeing it the + // class must not have been prepared yet since otherwise the fixup would have gotten the jobject + // to point to the final class object. + if (klass->IsTemp() || klass->IsRetired()) { + return ERR(CLASS_NOT_PREPARED); + } + + 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); +} + +jvmtiError ClassUtil::GetSourceFileName(jvmtiEnv* env, jclass jklass, char** source_name_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(ABSENT_INFORMATION); + } + JvmtiUniquePtr<char[]> source_copy; + const char* file_name = klass->GetSourceFile(); + if (file_name == nullptr) { + return ERR(ABSENT_INFORMATION); + } + jvmtiError ret; + source_copy = CopyString(env, file_name, &ret); + if (source_copy == nullptr) { + return ret; + } + *source_name_ptr = source_copy.release(); + return OK; +} + +jvmtiError ClassUtil::GetSourceDebugExtension(jvmtiEnv* env, + jclass jklass, + char** source_debug_extension_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::StackHandleScope<1> hs(art::Thread::Current()); + art::Handle<art::mirror::Class> klass(hs.NewHandle(jklass_obj->AsClass())); + if (klass->IsPrimitive() || klass->IsArrayClass()) { + return ERR(ABSENT_INFORMATION); + } + JvmtiUniquePtr<char[]> ext_copy; + const char* data = art::annotations::GetSourceDebugExtension(klass); + if (data == nullptr) { + return ERR(ABSENT_INFORMATION); + } + jvmtiError ret; + ext_copy = CopyString(env, data, &ret); + if (ext_copy == nullptr) { + return ret; + } + *source_debug_extension_ptr = ext_copy.release(); + return OK; +} + +} // namespace openjdkjvmti |