/*

 * Copyright (c) 2015, 2018, 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.

 *

 * 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 "precompiled.hpp"

#include "classfile/classLoaderData.hpp"

#include "classfile/moduleEntry.hpp"

#include "classfile/packageEntry.hpp"

#include "jfr/jfrEvents.hpp"

#include "jfr/periodic/jfrModuleEvent.hpp"

#include "jfr/utilities/jfrTime.hpp"

#include "runtime/mutexLocker.hpp"

// we want all periodic module events to have the same timestamp

static JfrTicks invocation_time;

typedef void (*EventFunc)(const void* iterated_address, const ModuleEntry* module);

class ModuleEventCallbackClosure : public ModuleClosure {

 protected:

  const EventFunc _event_func;

  ModuleEventCallbackClosure(EventFunc ef) : _event_func(ef) {}

};

class ModuleDependencyClosure : public ModuleEventCallbackClosure {

 private:

  const ModuleEntry* const _module;

 public:

   ModuleDependencyClosure(const ModuleEntry* module, EventFunc ef) : ModuleEventCallbackClosure(ef), _module(module) {}

   void do_module(ModuleEntry* entry);

};

class ModuleExportClosure : public ModuleEventCallbackClosure {

 private:

  const PackageEntry* const _package;

 public:

  ModuleExportClosure(const PackageEntry* pkg, EventFunc ef) : ModuleEventCallbackClosure(ef), _package(pkg) {}

  void do_module(ModuleEntry* entry);

};

static void write_module_dependency_event(const void* from_module, const ModuleEntry* to_module) {

  EventModuleRequire event(UNTIMED);

  event.set_endtime(invocation_time);

  event.set_source((const ModuleEntry* const)from_module);

  event.set_requiredModule(to_module);

  event.commit();

}

static void write_module_export_event(const void* package, const ModuleEntry* qualified_export) {

  EventModuleExport event(UNTIMED);

  event.set_endtime(invocation_time);

  event.set_exportedPackage((const PackageEntry*)package);

  event.set_targetModule(qualified_export);

  event.commit();

}

void ModuleDependencyClosure::do_module(ModuleEntry* to_module) {

  assert_locked_or_safepoint(Module_lock);

  assert(to_module != NULL, "invariant");

  assert(_module != NULL, "invariant");

  assert(_event_func != NULL, "invariant");

  _event_func(_module, to_module);

}

void ModuleExportClosure::do_module(ModuleEntry* qualified_export) {

  assert_locked_or_safepoint(Module_lock);

  assert(qualified_export != NULL, "invariant");

  assert(_package != NULL, "invariant");

  assert(_event_func != NULL, "invariant");

  _event_func(_package, qualified_export);

}

static void module_dependency_event_callback(ModuleEntry* module) {

  assert_locked_or_safepoint(Module_lock);

  assert(module != NULL, "invariant");

  if (module->has_reads_list()) {

    // create an individual event for each directed edge

    ModuleDependencyClosure directed_edges(module, &write_module_dependency_event);

    module->module_reads_do(&directed_edges);

  }

}

static void module_export_event_callback(PackageEntry* package) {

  assert_locked_or_safepoint(Module_lock);

  assert(package != NULL, "invariant");

  if (package->is_exported()) {

    if (package->has_qual_exports_list()) {

      // package is qualifiedly exported to a set of modules,

      // create an event for each module in the qualified exported list

      ModuleExportClosure qexports(package, &write_module_export_event);

      package->package_exports_do(&qexports);

      return;

    }

    assert(!package->is_qual_exported() || package->is_exported_allUnnamed(), "invariant");

    // no qualified exports

    // only create a single event with NULL

    // for the qualified_exports module

    write_module_export_event(package, NULL);

  }

}

void JfrModuleEvent::generate_module_dependency_events() {

  invocation_time = JfrTicks::now();

  MutexLockerEx module_lock(Module_lock);

  ClassLoaderDataGraph::modules_do(&module_dependency_event_callback);

}

void JfrModuleEvent::generate_module_export_events() {

  invocation_time = JfrTicks::now();

  MutexLockerEx module_lock(Module_lock);

  ClassLoaderDataGraph::packages_do(&module_export_event_callback);

}