duke@435: /*
coleenp@4037:  * Copyright (c) 2003, 2012, Oracle and/or its affiliates. All rights reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
stefank@2314: #include "precompiled.hpp"
stefank@2314: #include "classfile/systemDictionary.hpp"
stefank@2314: #include "memory/universe.inline.hpp"
stefank@2314: #include "prims/jvmtiGetLoadedClasses.hpp"
stefank@2314: #include "runtime/thread.hpp"
duke@435: 
duke@435: 
duke@435: 
duke@435: // The closure for GetLoadedClasses and GetClassLoaderClasses
duke@435: class JvmtiGetLoadedClassesClosure : public StackObj {
duke@435:   // Since the SystemDictionary::classes_do callback
duke@435:   // doesn't pass a closureData pointer,
duke@435:   // we use a thread-local slot to hold a pointer to
duke@435:   // a stack allocated instance of this structure.
duke@435:  private:
duke@435:   jobject _initiatingLoader;
duke@435:   int     _count;
duke@435:   Handle* _list;
duke@435:   int     _index;
duke@435: 
duke@435:  private:
duke@435:   // Getting and setting the thread local pointer
duke@435:   static JvmtiGetLoadedClassesClosure* get_this() {
duke@435:     JvmtiGetLoadedClassesClosure* result = NULL;
duke@435:     JavaThread* thread = JavaThread::current();
duke@435:     result = thread->get_jvmti_get_loaded_classes_closure();
duke@435:     return result;
duke@435:   }
duke@435:   static void set_this(JvmtiGetLoadedClassesClosure* that) {
duke@435:     JavaThread* thread = JavaThread::current();
duke@435:     thread->set_jvmti_get_loaded_classes_closure(that);
duke@435:   }
duke@435: 
duke@435:  public:
duke@435:   // Constructor/Destructor
duke@435:   JvmtiGetLoadedClassesClosure() {
duke@435:     JvmtiGetLoadedClassesClosure* that = get_this();
duke@435:     assert(that == NULL, "JvmtiGetLoadedClassesClosure in use");
duke@435:     _initiatingLoader = NULL;
duke@435:     _count = 0;
duke@435:     _list = NULL;
duke@435:     _index = 0;
duke@435:     set_this(this);
duke@435:   }
duke@435: 
duke@435:   JvmtiGetLoadedClassesClosure(jobject initiatingLoader) {
duke@435:     JvmtiGetLoadedClassesClosure* that = get_this();
duke@435:     assert(that == NULL, "JvmtiGetLoadedClassesClosure in use");
duke@435:     _initiatingLoader = initiatingLoader;
duke@435:     _count = 0;
duke@435:     _list = NULL;
duke@435:     _index = 0;
duke@435:     set_this(this);
duke@435:   }
duke@435: 
duke@435:   ~JvmtiGetLoadedClassesClosure() {
duke@435:     JvmtiGetLoadedClassesClosure* that = get_this();
duke@435:     assert(that != NULL, "JvmtiGetLoadedClassesClosure not found");
duke@435:     set_this(NULL);
duke@435:     _initiatingLoader = NULL;
duke@435:     _count = 0;
duke@435:     if (_list != NULL) {
duke@435:       FreeHeap(_list);
duke@435:       _list = NULL;
duke@435:     }
duke@435:     _index = 0;
duke@435:   }
duke@435: 
duke@435:   // Accessors.
duke@435:   jobject get_initiatingLoader() {
duke@435:     return _initiatingLoader;
duke@435:   }
duke@435: 
duke@435:   int get_count() {
duke@435:     return _count;
duke@435:   }
duke@435: 
duke@435:   void set_count(int value) {
duke@435:     _count = value;
duke@435:   }
duke@435: 
duke@435:   Handle* get_list() {
duke@435:     return _list;
duke@435:   }
duke@435: 
duke@435:   void set_list(Handle* value) {
duke@435:     _list = value;
duke@435:   }
duke@435: 
duke@435:   int get_index() {
duke@435:     return _index;
duke@435:   }
duke@435: 
duke@435:   void set_index(int value) {
duke@435:     _index = value;
duke@435:   }
duke@435: 
duke@435:   Handle get_element(int index) {
duke@435:     if ((_list != NULL) && (index < _count)) {
duke@435:       return _list[index];
duke@435:     } else {
duke@435:       assert(false, "empty get_element");
duke@435:       return Handle();
duke@435:     }
duke@435:   }
duke@435: 
duke@435:   void set_element(int index, Handle value) {
duke@435:     if ((_list != NULL) && (index < _count)) {
duke@435:       _list[index] = value;
duke@435:     } else {
duke@435:       assert(false, "bad set_element");
duke@435:     }
duke@435:   }
duke@435: 
duke@435:   // Other predicates
duke@435:   bool available() {
duke@435:     return (_list != NULL);
duke@435:   }
duke@435: 
duke@435: #ifdef ASSERT
duke@435:   // For debugging.
duke@435:   void check(int limit) {
duke@435:     for (int i = 0; i < limit; i += 1) {
duke@435:       assert(Universe::heap()->is_in(get_element(i)()), "check fails");
duke@435:     }
duke@435:   }
duke@435: #endif
duke@435: 
duke@435:   // Public methods that get called within the scope of the closure
duke@435:   void allocate() {
zgu@3900:     _list = NEW_C_HEAP_ARRAY(Handle, _count, mtInternal);
duke@435:     assert(_list != NULL, "Out of memory");
duke@435:     if (_list == NULL) {
duke@435:       _count = 0;
duke@435:     }
duke@435:   }
duke@435: 
duke@435:   void extract(JvmtiEnv *env, jclass* result) {
duke@435:     for (int index = 0; index < _count; index += 1) {
duke@435:       result[index] = (jclass) env->jni_reference(get_element(index));
duke@435:     }
duke@435:   }
duke@435: 
duke@435:   // Finally, the static methods that are the callbacks
coleenp@4037:   static void increment(Klass* k) {
duke@435:     JvmtiGetLoadedClassesClosure* that = JvmtiGetLoadedClassesClosure::get_this();
duke@435:     if (that->get_initiatingLoader() == NULL) {
hseigel@4278:       for (Klass* l = k; l != NULL; l = l->array_klass_or_null()) {
duke@435:         that->set_count(that->get_count() + 1);
duke@435:       }
duke@435:     } else if (k != NULL) {
duke@435:       // if initiating loader not null, just include the instance with 1 dimension
duke@435:       that->set_count(that->get_count() + 1);
duke@435:     }
duke@435:   }
duke@435: 
coleenp@4037:   static void increment_with_loader(Klass* k, ClassLoaderData* loader_data) {
duke@435:     JvmtiGetLoadedClassesClosure* that = JvmtiGetLoadedClassesClosure::get_this();
coleenp@4037:     oop class_loader = loader_data->class_loader();
coleenp@4037:     if (class_loader == JNIHandles::resolve(that->get_initiatingLoader())) {
hseigel@4278:       for (Klass* l = k; l != NULL; l = l->array_klass_or_null()) {
duke@435:         that->set_count(that->get_count() + 1);
duke@435:       }
duke@435:     }
duke@435:   }
duke@435: 
coleenp@4037:   static void prim_array_increment_with_loader(Klass* array, ClassLoaderData* loader_data) {
duke@435:     JvmtiGetLoadedClassesClosure* that = JvmtiGetLoadedClassesClosure::get_this();
coleenp@4037:     oop class_loader = loader_data->class_loader();
coleenp@4037:     if (class_loader == JNIHandles::resolve(that->get_initiatingLoader())) {
duke@435:       that->set_count(that->get_count() + 1);
duke@435:     }
duke@435:   }
duke@435: 
coleenp@4037:   static void add(Klass* k) {
duke@435:     JvmtiGetLoadedClassesClosure* that = JvmtiGetLoadedClassesClosure::get_this();
duke@435:     if (that->available()) {
duke@435:       if (that->get_initiatingLoader() == NULL) {
hseigel@4278:         for (Klass* l = k; l != NULL; l = l->array_klass_or_null()) {
hseigel@4278:           oop mirror = l->java_mirror();
duke@435:           that->set_element(that->get_index(), mirror);
duke@435:           that->set_index(that->get_index() + 1);
duke@435:         }
duke@435:       } else if (k != NULL) {
duke@435:         // if initiating loader not null, just include the instance with 1 dimension
hseigel@4278:         oop mirror = k->java_mirror();
duke@435:         that->set_element(that->get_index(), mirror);
duke@435:         that->set_index(that->get_index() + 1);
duke@435:       }
duke@435:     }
duke@435:   }
duke@435: 
coleenp@4037:   static void add_with_loader(Klass* k, ClassLoaderData* loader_data) {
duke@435:     JvmtiGetLoadedClassesClosure* that = JvmtiGetLoadedClassesClosure::get_this();
duke@435:     if (that->available()) {
coleenp@4037:       oop class_loader = loader_data->class_loader();
coleenp@4037:       if (class_loader == JNIHandles::resolve(that->get_initiatingLoader())) {
hseigel@4278:         for (Klass* l = k; l != NULL; l = l->array_klass_or_null()) {
hseigel@4278:           oop mirror = l->java_mirror();
duke@435:           that->set_element(that->get_index(), mirror);
duke@435:           that->set_index(that->get_index() + 1);
duke@435:         }
duke@435:       }
duke@435:     }
duke@435:   }
duke@435: 
duke@435:   // increment the count for the given basic type array class (and any
duke@435:   // multi-dimensional arrays). For example, for [B we check for
duke@435:   // [[B, [[[B, .. and the count is incremented for each one that exists.
coleenp@4037:   static void increment_for_basic_type_arrays(Klass* k) {
duke@435:     JvmtiGetLoadedClassesClosure* that = JvmtiGetLoadedClassesClosure::get_this();
duke@435:     assert(that != NULL, "no JvmtiGetLoadedClassesClosure");
hseigel@4278:     for (Klass* l = k; l != NULL; l = l->array_klass_or_null()) {
duke@435:       that->set_count(that->get_count() + 1);
duke@435:     }
duke@435:   }
duke@435: 
duke@435:   // add the basic type array class and its multi-dimensional array classes to the list
coleenp@4037:   static void add_for_basic_type_arrays(Klass* k) {
duke@435:     JvmtiGetLoadedClassesClosure* that = JvmtiGetLoadedClassesClosure::get_this();
duke@435:     assert(that != NULL, "no JvmtiGetLoadedClassesClosure");
duke@435:     assert(that->available(), "no list");
hseigel@4278:     for (Klass* l = k; l != NULL; l = l->array_klass_or_null()) {
hseigel@4278:       oop mirror = l->java_mirror();
duke@435:       that->set_element(that->get_index(), mirror);
duke@435:       that->set_index(that->get_index() + 1);
duke@435:     }
duke@435:   }
duke@435: };
duke@435: 
duke@435: 
duke@435: jvmtiError
duke@435: JvmtiGetLoadedClasses::getLoadedClasses(JvmtiEnv *env, jint* classCountPtr, jclass** classesPtr) {
duke@435:   // Since SystemDictionary::classes_do only takes a function pointer
duke@435:   // and doesn't call back with a closure data pointer,
duke@435:   // we can only pass static methods.
duke@435: 
duke@435:   JvmtiGetLoadedClassesClosure closure;
duke@435:   {
duke@435:     // To get a consistent list of classes we need MultiArray_lock to ensure
duke@435:     // array classes aren't created, and SystemDictionary_lock to ensure that
duke@435:     // classes aren't added to the system dictionary,
duke@435:     MutexLocker ma(MultiArray_lock);
duke@435:     MutexLocker sd(SystemDictionary_lock);
duke@435: 
duke@435:     // First, count the classes
duke@435:     SystemDictionary::classes_do(&JvmtiGetLoadedClassesClosure::increment);
duke@435:     Universe::basic_type_classes_do(&JvmtiGetLoadedClassesClosure::increment);
duke@435:     // Next, fill in the classes
duke@435:     closure.allocate();
duke@435:     SystemDictionary::classes_do(&JvmtiGetLoadedClassesClosure::add);
duke@435:     Universe::basic_type_classes_do(&JvmtiGetLoadedClassesClosure::add);
duke@435:     // Drop the SystemDictionary_lock, so the results could be wrong from here,
duke@435:     // but we still have a snapshot.
duke@435:   }
duke@435:   // Post results
duke@435:   jclass* result_list;
duke@435:   jvmtiError err = env->Allocate(closure.get_count() * sizeof(jclass),
duke@435:                                  (unsigned char**)&result_list);
duke@435:   if (err != JVMTI_ERROR_NONE) {
duke@435:     return err;
duke@435:   }
duke@435:   closure.extract(env, result_list);
duke@435:   *classCountPtr = closure.get_count();
duke@435:   *classesPtr = result_list;
duke@435:   return JVMTI_ERROR_NONE;
duke@435: }
duke@435: 
duke@435: jvmtiError
duke@435: JvmtiGetLoadedClasses::getClassLoaderClasses(JvmtiEnv *env, jobject initiatingLoader,
duke@435:                                              jint* classCountPtr, jclass** classesPtr) {
duke@435:   // Since SystemDictionary::classes_do only takes a function pointer
duke@435:   // and doesn't call back with a closure data pointer,
duke@435:   // we can only pass static methods.
duke@435:   JvmtiGetLoadedClassesClosure closure(initiatingLoader);
duke@435:   {
duke@435:     // To get a consistent list of classes we need MultiArray_lock to ensure
duke@435:     // array classes aren't created, and SystemDictionary_lock to ensure that
duke@435:     // classes aren't added to the system dictionary,
duke@435:     MutexLocker ma(MultiArray_lock);
duke@435:     MutexLocker sd(SystemDictionary_lock);
duke@435:     // First, count the classes in the system dictionary which have this loader recorded
duke@435:     // as an initiating loader. For basic type arrays this information is not recorded
duke@435:     // so GetClassLoaderClasses will return all of the basic type arrays. This is okay
duke@435:     // because the defining loader for basic type arrays is always the boot class loader
duke@435:     // and these classes are "visible" to all loaders.
duke@435:     SystemDictionary::classes_do(&JvmtiGetLoadedClassesClosure::increment_with_loader);
duke@435:     Universe::basic_type_classes_do(&JvmtiGetLoadedClassesClosure::increment_for_basic_type_arrays);
duke@435:     // Next, fill in the classes
duke@435:     closure.allocate();
duke@435:     SystemDictionary::classes_do(&JvmtiGetLoadedClassesClosure::add_with_loader);
duke@435:     Universe::basic_type_classes_do(&JvmtiGetLoadedClassesClosure::add_for_basic_type_arrays);
duke@435:     // Drop the SystemDictionary_lock, so the results could be wrong from here,
duke@435:     // but we still have a snapshot.
duke@435:   }
duke@435:   // Post results
duke@435:   jclass* result_list;
duke@435:   jvmtiError err = env->Allocate(closure.get_count() * sizeof(jclass),
duke@435:                                  (unsigned char**)&result_list);
duke@435:   if (err != JVMTI_ERROR_NONE) {
duke@435:     return err;
duke@435:   }
duke@435:   closure.extract(env, result_list);
duke@435:   *classCountPtr = closure.get_count();
duke@435:   *classesPtr = result_list;
duke@435:   return JVMTI_ERROR_NONE;
duke@435: }