/*
 * Copyright (c) 2014, 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 "memory/metaspaceTracer.hpp"
#include "runtime/frame.hpp"
#include "runtime/os.hpp"
#include "runtime/thread.inline.hpp"
#include "trace/tracing.hpp"
#include "trace/traceBackend.hpp"
#include "utilities/decoder.hpp"
#include "utilities/ostream.hpp"

void MetaspaceTracer::report_gc_threshold(size_t old_val,
                                          size_t new_val,
                                          MetaspaceGCThresholdUpdater::Type updater) const {
  EventMetaspaceGCThreshold event;
  if (event.should_commit()) {
    event.set_oldValue(old_val);
    event.set_newValue(new_val);
    event.set_updater((u1)updater);
    event.commit();
  }
}

static bool get_method_name(address pc, char *buf, size_t buflen) {
  if (os::address_is_in_vm(pc) && Decoder::can_decode_C_frame_in_vm()) {
    return os::dll_address_to_function_name(pc, buf, (int) buflen, 0);
  }
  return false;
}

static bool is_valid_frame_in_vm(const frame* f) {
  return f->pc() && os::address_is_in_vm(f->pc()) && !f->is_java_frame();
}

static void write_vm_stack_trace(outputStream *stream) {
  const size_t max_num_frames = 64;
  size_t num_frames = 0;

  const size_t buflen = 256;
  char *buf = NEW_RESOURCE_ARRAY(char, buflen);

  Thread* current_thread = Thread::current();
  frame fr = os::current_frame();
  while (is_valid_frame_in_vm(&fr) && num_frames < max_num_frames) {
    if (get_method_name(fr.pc(), buf, buflen)) {
      stream->print_cr("%s", buf);
    } else {
      stream->print_cr(PTR_FORMAT, fr.pc());
    }

    // Check if it safe to get the caller's stack frame.
    if (fr.safe_for_sender(current_thread)) {
      fr = os::get_sender_for_C_frame(&fr);
    } else {
      // Not safe to traverse the stack any further.
      return;
    }

    num_frames++;
  }
}

void MetaspaceTracer::report_metaspace_allocation_failure(ClassLoaderData *cld,
                                                          size_t word_size,
                                                          MetaspaceObj::Type objtype,
                                                          Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceAllocationFailure>(cld, word_size, objtype, mdtype);
}

void MetaspaceTracer::report_metadata_oom(ClassLoaderData *cld,
                                         size_t word_size,
                                         MetaspaceObj::Type objtype,
                                         Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceOOM>(cld, word_size, objtype, mdtype);
}

template <typename E>
void MetaspaceTracer::send_allocation_failure_event(ClassLoaderData *cld,
                                                    size_t word_size,
                                                    MetaspaceObj::Type objtype,
                                                    Metaspace::MetadataType mdtype) const {
  E event;
  if (event.should_commit()) {
    if (cld->is_anonymous()) {
      event.set_classLoader(NULL);
      event.set_anonymousClassLoader(true);
    } else {
      if (cld->is_the_null_class_loader_data()) {
        event.set_classLoader((Klass*) NULL);
      } else {
        event.set_classLoader(cld->class_loader()->klass());
      }
      event.set_anonymousClassLoader(false);
    }

#ifdef _WINDOWS
    // Can not walk the stack on Windows using the frame pointer.
    event.set_nativeStackTrace(NULL);
#else
    ResourceMark rm;
    stringStream stack_trace;
    write_vm_stack_trace(&stack_trace);
    event.set_nativeStackTrace(stack_trace.as_string());
#endif

    event.set_size(word_size * BytesPerWord);
    event.set_metadataType((u1) mdtype);
    event.set_metaspaceObjectType((u1) objtype);
    event.commit();
  }
}