ART: Move openjdkjvmti to art/

Move libopenjdkjvmti out of the runtime directory. Let's not
pollute the runtime library.

Test: m test-art-host
Change-Id: Idb6b9cebcd61777bd3200437a2ae584a63a4a341
diff --git a/openjdkjvmti/events-inl.h b/openjdkjvmti/events-inl.h
new file mode 100644
index 0000000..32dba3e
--- /dev/null
+++ b/openjdkjvmti/events-inl.h
@@ -0,0 +1,440 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_OPENJDKJVMTI_EVENTS_INL_H_
+#define ART_OPENJDKJVMTI_EVENTS_INL_H_
+
+#include <array>
+
+#include "events.h"
+#include "jni_internal.h"
+#include "nativehelper/ScopedLocalRef.h"
+#include "ti_breakpoint.h"
+
+#include "art_jvmti.h"
+
+namespace openjdkjvmti {
+
+static inline ArtJvmtiEvent GetArtJvmtiEvent(ArtJvmTiEnv* env, jvmtiEvent e) {
+  if (UNLIKELY(e == JVMTI_EVENT_CLASS_FILE_LOAD_HOOK)) {
+    if (env->capabilities.can_retransform_classes) {
+      return ArtJvmtiEvent::kClassFileLoadHookRetransformable;
+    } else {
+      return ArtJvmtiEvent::kClassFileLoadHookNonRetransformable;
+    }
+  } else {
+    return static_cast<ArtJvmtiEvent>(e);
+  }
+}
+
+namespace impl {
+
+// Infrastructure to achieve type safety for event dispatch.
+
+#define FORALL_EVENT_TYPES(fn)                                                       \
+  fn(VMInit,                  ArtJvmtiEvent::kVmInit)                                \
+  fn(VMDeath,                 ArtJvmtiEvent::kVmDeath)                               \
+  fn(ThreadStart,             ArtJvmtiEvent::kThreadStart)                           \
+  fn(ThreadEnd,               ArtJvmtiEvent::kThreadEnd)                             \
+  fn(ClassFileLoadHook,       ArtJvmtiEvent::kClassFileLoadHookRetransformable)      \
+  fn(ClassFileLoadHook,       ArtJvmtiEvent::kClassFileLoadHookNonRetransformable)   \
+  fn(ClassLoad,               ArtJvmtiEvent::kClassLoad)                             \
+  fn(ClassPrepare,            ArtJvmtiEvent::kClassPrepare)                          \
+  fn(VMStart,                 ArtJvmtiEvent::kVmStart)                               \
+  fn(Exception,               ArtJvmtiEvent::kException)                             \
+  fn(ExceptionCatch,          ArtJvmtiEvent::kExceptionCatch)                        \
+  fn(SingleStep,              ArtJvmtiEvent::kSingleStep)                            \
+  fn(FramePop,                ArtJvmtiEvent::kFramePop)                              \
+  fn(Breakpoint,              ArtJvmtiEvent::kBreakpoint)                            \
+  fn(FieldAccess,             ArtJvmtiEvent::kFieldAccess)                           \
+  fn(FieldModification,       ArtJvmtiEvent::kFieldModification)                     \
+  fn(MethodEntry,             ArtJvmtiEvent::kMethodEntry)                           \
+  fn(MethodExit,              ArtJvmtiEvent::kMethodExit)                            \
+  fn(NativeMethodBind,        ArtJvmtiEvent::kNativeMethodBind)                      \
+  fn(CompiledMethodLoad,      ArtJvmtiEvent::kCompiledMethodLoad)                    \
+  fn(CompiledMethodUnload,    ArtJvmtiEvent::kCompiledMethodUnload)                  \
+  fn(DynamicCodeGenerated,    ArtJvmtiEvent::kDynamicCodeGenerated)                  \
+  fn(DataDumpRequest,         ArtJvmtiEvent::kDataDumpRequest)                       \
+  fn(MonitorWait,             ArtJvmtiEvent::kMonitorWait)                           \
+  fn(MonitorWaited,           ArtJvmtiEvent::kMonitorWaited)                         \
+  fn(MonitorContendedEnter,   ArtJvmtiEvent::kMonitorContendedEnter)                 \
+  fn(MonitorContendedEntered, ArtJvmtiEvent::kMonitorContendedEntered)               \
+  fn(ResourceExhausted,       ArtJvmtiEvent::kResourceExhausted)                     \
+  fn(GarbageCollectionStart,  ArtJvmtiEvent::kGarbageCollectionStart)                \
+  fn(GarbageCollectionFinish, ArtJvmtiEvent::kGarbageCollectionFinish)               \
+  fn(ObjectFree,              ArtJvmtiEvent::kObjectFree)                            \
+  fn(VMObjectAlloc,           ArtJvmtiEvent::kVmObjectAlloc)
+
+template <ArtJvmtiEvent kEvent>
+struct EventFnType {
+};
+
+#define EVENT_FN_TYPE(name, enum_name)               \
+template <>                                          \
+struct EventFnType<enum_name> {                      \
+  using type = decltype(jvmtiEventCallbacks().name); \
+};
+
+FORALL_EVENT_TYPES(EVENT_FN_TYPE)
+
+#undef EVENT_FN_TYPE
+
+template <ArtJvmtiEvent kEvent>
+ALWAYS_INLINE inline typename EventFnType<kEvent>::type GetCallback(ArtJvmTiEnv* env);
+
+#define GET_CALLBACK(name, enum_name)                                     \
+template <>                                                               \
+ALWAYS_INLINE inline EventFnType<enum_name>::type GetCallback<enum_name>( \
+    ArtJvmTiEnv* env) {                                                   \
+  if (env->event_callbacks == nullptr) {                                  \
+    return nullptr;                                                       \
+  }                                                                       \
+  return env->event_callbacks->name;                                      \
+}
+
+FORALL_EVENT_TYPES(GET_CALLBACK)
+
+#undef GET_CALLBACK
+
+#undef FORALL_EVENT_TYPES
+
+}  // namespace impl
+
+// C++ does not allow partial template function specialization. The dispatch for our separated
+// ClassFileLoadHook event types is the same, so use this helper for code deduplication.
+// TODO Locking of some type!
+template <ArtJvmtiEvent kEvent>
+inline void EventHandler::DispatchClassFileLoadHookEvent(art::Thread* thread,
+                                                         JNIEnv* jnienv,
+                                                         jclass class_being_redefined,
+                                                         jobject loader,
+                                                         const char* name,
+                                                         jobject protection_domain,
+                                                         jint class_data_len,
+                                                         const unsigned char* class_data,
+                                                         jint* new_class_data_len,
+                                                         unsigned char** new_class_data) const {
+  static_assert(kEvent == ArtJvmtiEvent::kClassFileLoadHookRetransformable ||
+                kEvent == ArtJvmtiEvent::kClassFileLoadHookNonRetransformable, "Unsupported event");
+  DCHECK(*new_class_data == nullptr);
+  jint current_len = class_data_len;
+  unsigned char* current_class_data = const_cast<unsigned char*>(class_data);
+  ArtJvmTiEnv* last_env = nullptr;
+  for (ArtJvmTiEnv* env : envs) {
+    if (env == nullptr) {
+      continue;
+    }
+    if (ShouldDispatch<kEvent>(env, thread)) {
+      ScopedLocalRef<jthrowable> thr(jnienv, jnienv->ExceptionOccurred());
+      jnienv->ExceptionClear();
+      jint new_len = 0;
+      unsigned char* new_data = nullptr;
+      auto callback = impl::GetCallback<kEvent>(env);
+      callback(env,
+               jnienv,
+               class_being_redefined,
+               loader,
+               name,
+               protection_domain,
+               current_len,
+               current_class_data,
+               &new_len,
+               &new_data);
+      if (thr.get() != nullptr && !jnienv->ExceptionCheck()) {
+        jnienv->Throw(thr.get());
+      }
+      if (new_data != nullptr && new_data != current_class_data) {
+        // Destroy the data the last transformer made. We skip this if the previous state was the
+        // initial one since we don't know here which jvmtiEnv allocated it.
+        // NB Currently this doesn't matter since all allocations just go to malloc but in the
+        // future we might have jvmtiEnv's keep track of their allocations for leak-checking.
+        if (last_env != nullptr) {
+          last_env->Deallocate(current_class_data);
+        }
+        last_env = env;
+        current_class_data = new_data;
+        current_len = new_len;
+      }
+    }
+  }
+  if (last_env != nullptr) {
+    *new_class_data_len = current_len;
+    *new_class_data = current_class_data;
+  }
+}
+
+// Our goal for DispatchEvent: Do not allow implicit type conversion. Types of ...args must match
+// exactly the argument types of the corresponding Jvmti kEvent function pointer.
+
+template <ArtJvmtiEvent kEvent, typename ...Args>
+inline void EventHandler::DispatchEvent(art::Thread* thread, Args... args) const {
+  for (ArtJvmTiEnv* env : envs) {
+    if (env != nullptr) {
+      DispatchEvent<kEvent, Args...>(env, thread, args...);
+    }
+  }
+}
+
+// Events with JNIEnvs need to stash pending exceptions since they can cause new ones to be thrown.
+// In accordance with the JVMTI specification we allow exceptions originating from events to
+// overwrite the current exception, including exceptions originating from earlier events.
+// TODO It would be nice to add the overwritten exceptions to the suppressed exceptions list of the
+// newest exception.
+template <ArtJvmtiEvent kEvent, typename ...Args>
+inline void EventHandler::DispatchEvent(art::Thread* thread, JNIEnv* jnienv, Args... args) const {
+  for (ArtJvmTiEnv* env : envs) {
+    if (env != nullptr) {
+      ScopedLocalRef<jthrowable> thr(jnienv, jnienv->ExceptionOccurred());
+      jnienv->ExceptionClear();
+      DispatchEvent<kEvent, JNIEnv*, Args...>(env, thread, jnienv, args...);
+      if (thr.get() != nullptr && !jnienv->ExceptionCheck()) {
+        jnienv->Throw(thr.get());
+      }
+    }
+  }
+}
+
+template <ArtJvmtiEvent kEvent, typename ...Args>
+inline void EventHandler::DispatchEvent(ArtJvmTiEnv* env, art::Thread* thread, Args... args) const {
+  using FnType = void(jvmtiEnv*, Args...);
+  if (ShouldDispatch<kEvent>(env, thread)) {
+    FnType* callback = impl::GetCallback<kEvent>(env);
+    if (callback != nullptr) {
+      (*callback)(env, args...);
+    }
+  }
+}
+
+// Need to give custom specializations for Breakpoint since it needs to filter out which particular
+// methods/dex_pcs agents get notified on.
+template <>
+inline void EventHandler::DispatchEvent<ArtJvmtiEvent::kBreakpoint>(art::Thread* thread,
+                                                                    JNIEnv* jnienv,
+                                                                    jthread jni_thread,
+                                                                    jmethodID jmethod,
+                                                                    jlocation location) const {
+  art::ArtMethod* method = art::jni::DecodeArtMethod(jmethod);
+  for (ArtJvmTiEnv* env : envs) {
+    // Search for a breakpoint on this particular method and location.
+    if (env != nullptr &&
+        ShouldDispatch<ArtJvmtiEvent::kBreakpoint>(env, thread) &&
+        env->breakpoints.find({method, location}) != env->breakpoints.end()) {
+      // We temporarily clear any pending exceptions so the event can call back into java code.
+      ScopedLocalRef<jthrowable> thr(jnienv, jnienv->ExceptionOccurred());
+      jnienv->ExceptionClear();
+      auto callback = impl::GetCallback<ArtJvmtiEvent::kBreakpoint>(env);
+      (*callback)(env, jnienv, jni_thread, jmethod, location);
+      if (thr.get() != nullptr && !jnienv->ExceptionCheck()) {
+        jnienv->Throw(thr.get());
+      }
+    }
+  }
+}
+
+// Need to give custom specializations for FieldAccess and FieldModification since they need to
+// filter out which particular fields agents want to get notified on.
+// TODO The spec allows us to do shortcuts like only allow one agent to ever set these watches. This
+// could make the system more performant.
+template <>
+inline void EventHandler::DispatchEvent<ArtJvmtiEvent::kFieldModification>(art::Thread* thread,
+                                                                           JNIEnv* jnienv,
+                                                                           jthread jni_thread,
+                                                                           jmethodID method,
+                                                                           jlocation location,
+                                                                           jclass field_klass,
+                                                                           jobject object,
+                                                                           jfieldID field,
+                                                                           char type_char,
+                                                                           jvalue val) const {
+  for (ArtJvmTiEnv* env : envs) {
+    if (env != nullptr &&
+        ShouldDispatch<ArtJvmtiEvent::kFieldModification>(env, thread) &&
+        env->modify_watched_fields.find(
+            art::jni::DecodeArtField(field)) != env->modify_watched_fields.end()) {
+      ScopedLocalRef<jthrowable> thr(jnienv, jnienv->ExceptionOccurred());
+      jnienv->ExceptionClear();
+      auto callback = impl::GetCallback<ArtJvmtiEvent::kFieldModification>(env);
+      (*callback)(env,
+                  jnienv,
+                  jni_thread,
+                  method,
+                  location,
+                  field_klass,
+                  object,
+                  field,
+                  type_char,
+                  val);
+      if (thr.get() != nullptr && !jnienv->ExceptionCheck()) {
+        jnienv->Throw(thr.get());
+      }
+    }
+  }
+}
+
+template <>
+inline void EventHandler::DispatchEvent<ArtJvmtiEvent::kFieldAccess>(art::Thread* thread,
+                                                                     JNIEnv* jnienv,
+                                                                     jthread jni_thread,
+                                                                     jmethodID method,
+                                                                     jlocation location,
+                                                                     jclass field_klass,
+                                                                     jobject object,
+                                                                     jfieldID field) const {
+  for (ArtJvmTiEnv* env : envs) {
+    if (env != nullptr &&
+        ShouldDispatch<ArtJvmtiEvent::kFieldAccess>(env, thread) &&
+        env->access_watched_fields.find(
+            art::jni::DecodeArtField(field)) != env->access_watched_fields.end()) {
+      ScopedLocalRef<jthrowable> thr(jnienv, jnienv->ExceptionOccurred());
+      jnienv->ExceptionClear();
+      auto callback = impl::GetCallback<ArtJvmtiEvent::kFieldAccess>(env);
+      (*callback)(env, jnienv, jni_thread, method, location, field_klass, object, field);
+      if (thr.get() != nullptr && !jnienv->ExceptionCheck()) {
+        jnienv->Throw(thr.get());
+      }
+    }
+  }
+}
+
+// Need to give a custom specialization for NativeMethodBind since it has to deal with an out
+// variable.
+template <>
+inline void EventHandler::DispatchEvent<ArtJvmtiEvent::kNativeMethodBind>(art::Thread* thread,
+                                                                          JNIEnv* jnienv,
+                                                                          jthread jni_thread,
+                                                                          jmethodID method,
+                                                                          void* cur_method,
+                                                                          void** new_method) const {
+  *new_method = cur_method;
+  for (ArtJvmTiEnv* env : envs) {
+    if (env != nullptr && ShouldDispatch<ArtJvmtiEvent::kNativeMethodBind>(env, thread)) {
+      auto callback = impl::GetCallback<ArtJvmtiEvent::kNativeMethodBind>(env);
+      (*callback)(env, jnienv, jni_thread, method, cur_method, new_method);
+      if (*new_method != nullptr) {
+        cur_method = *new_method;
+      }
+    }
+  }
+}
+
+// C++ does not allow partial template function specialization. The dispatch for our separated
+// ClassFileLoadHook event types is the same, and in the DispatchClassFileLoadHookEvent helper.
+// The following two DispatchEvent specializations dispatch to it.
+template <>
+inline void EventHandler::DispatchEvent<ArtJvmtiEvent::kClassFileLoadHookRetransformable>(
+    art::Thread* thread,
+    JNIEnv* jnienv,
+    jclass class_being_redefined,
+    jobject loader,
+    const char* name,
+    jobject protection_domain,
+    jint class_data_len,
+    const unsigned char* class_data,
+    jint* new_class_data_len,
+    unsigned char** new_class_data) const {
+  return DispatchClassFileLoadHookEvent<ArtJvmtiEvent::kClassFileLoadHookRetransformable>(
+      thread,
+      jnienv,
+      class_being_redefined,
+      loader,
+      name,
+      protection_domain,
+      class_data_len,
+      class_data,
+      new_class_data_len,
+      new_class_data);
+}
+template <>
+inline void EventHandler::DispatchEvent<ArtJvmtiEvent::kClassFileLoadHookNonRetransformable>(
+    art::Thread* thread,
+    JNIEnv* jnienv,
+    jclass class_being_redefined,
+    jobject loader,
+    const char* name,
+    jobject protection_domain,
+    jint class_data_len,
+    const unsigned char* class_data,
+    jint* new_class_data_len,
+    unsigned char** new_class_data) const {
+  return DispatchClassFileLoadHookEvent<ArtJvmtiEvent::kClassFileLoadHookNonRetransformable>(
+      thread,
+      jnienv,
+      class_being_redefined,
+      loader,
+      name,
+      protection_domain,
+      class_data_len,
+      class_data,
+      new_class_data_len,
+      new_class_data);
+}
+
+template <ArtJvmtiEvent kEvent>
+inline bool EventHandler::ShouldDispatch(ArtJvmTiEnv* env,
+                                         art::Thread* thread) {
+  bool dispatch = env->event_masks.global_event_mask.Test(kEvent);
+
+  if (!dispatch && thread != nullptr && env->event_masks.unioned_thread_event_mask.Test(kEvent)) {
+    EventMask* mask = env->event_masks.GetEventMaskOrNull(thread);
+    dispatch = mask != nullptr && mask->Test(kEvent);
+  }
+  return dispatch;
+}
+
+inline void EventHandler::RecalculateGlobalEventMask(ArtJvmtiEvent event) {
+  bool union_value = false;
+  for (const ArtJvmTiEnv* stored_env : envs) {
+    if (stored_env == nullptr) {
+      continue;
+    }
+    union_value |= stored_env->event_masks.global_event_mask.Test(event);
+    union_value |= stored_env->event_masks.unioned_thread_event_mask.Test(event);
+    if (union_value) {
+      break;
+    }
+  }
+  global_mask.Set(event, union_value);
+}
+
+inline bool EventHandler::NeedsEventUpdate(ArtJvmTiEnv* env,
+                                           const jvmtiCapabilities& caps,
+                                           bool added) {
+  ArtJvmtiEvent event = added ? ArtJvmtiEvent::kClassFileLoadHookNonRetransformable
+                              : ArtJvmtiEvent::kClassFileLoadHookRetransformable;
+  return (added && caps.can_access_local_variables == 1) ||
+      (caps.can_retransform_classes == 1 &&
+       IsEventEnabledAnywhere(event) &&
+       env->event_masks.IsEnabledAnywhere(event));
+}
+
+inline void EventHandler::HandleChangedCapabilities(ArtJvmTiEnv* env,
+                                                    const jvmtiCapabilities& caps,
+                                                    bool added) {
+  if (UNLIKELY(NeedsEventUpdate(env, caps, added))) {
+    env->event_masks.HandleChangedCapabilities(caps, added);
+    if (caps.can_retransform_classes == 1) {
+      RecalculateGlobalEventMask(ArtJvmtiEvent::kClassFileLoadHookRetransformable);
+      RecalculateGlobalEventMask(ArtJvmtiEvent::kClassFileLoadHookNonRetransformable);
+    }
+    if (added && caps.can_access_local_variables == 1) {
+      HandleLocalAccessCapabilityAdded();
+    }
+  }
+}
+
+}  // namespace openjdkjvmti
+
+#endif  // ART_OPENJDKJVMTI_EVENTS_INL_H_