/*
 * Copyright (c) 2024, 2025, 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.
 *
 */

#ifndef SHARE_NMT_MEMORYFILETRACKER_HPP
#define SHARE_NMT_MEMORYFILETRACKER_HPP

#include "memory/allocation.hpp"
#include "nmt/nmtCommon.hpp"
#include "nmt/nmtNativeCallStackStorage.hpp"
#include "nmt/vmatree.hpp"
#include "nmt/virtualMemoryTracker.hpp"
#include "runtime/os.inline.hpp"
#include "utilities/growableArray.hpp"
#include "utilities/nativeCallStack.hpp"
#include "utilities/ostream.hpp"
#include "utilities/deferred.hpp"

// The MemoryFileTracker tracks memory of 'memory files',
// storage with its own memory space separate from the process.
// A typical example of such a file is a memory mapped file.
// All memory is accounted as committed, there is no reserved memory.
// Any reserved memory is expected to exist in the VirtualMemoryTracker.
class MemoryFileTracker {
  friend class NMTMemoryFileTrackerTest;

  // Provide caching of stacks.
  NativeCallStackStorage _stack_storage;

public:
  class MemoryFile : public CHeapObj<mtNMT> {
    friend MemoryFileTracker;
    friend class NMTMemoryFileTrackerTest;
    const char* _descriptive_name;
    VirtualMemorySnapshot _summary;
    VMATree _tree;
  public:
    NONCOPYABLE(MemoryFile);
    MemoryFile(const char* descriptive_name)
      : _descriptive_name(descriptive_name) {}
  };

private:
  // We need pointers to each allocated file.
  GrowableArrayCHeap<MemoryFile*, mtNMT> _files;

public:
  MemoryFileTracker(bool is_detailed_mode);

  void allocate_memory(MemoryFile* file, size_t offset, size_t size, const NativeCallStack& stack,
                       MemTag mem_tag);
  void free_memory(MemoryFile* file, size_t offset, size_t size);

  MemoryFile* make_file(const char* descriptive_name);
  void free_file(MemoryFile* file);

  template<typename F>
  void iterate_summary(F f) const {
    for (int d = 0; d < _files.length(); d++) {
      const MemoryFile* file = _files.at(d);
      for (int i = 0; i < mt_number_of_tags; i++) {
        f(NMTUtil::index_to_tag(i), file->_summary.by_tag(NMTUtil::index_to_tag(i)));
      }
    }
  }

  void summary_snapshot(VirtualMemorySnapshot* snapshot) const;

  // Print detailed report of file
  void print_report_on(const MemoryFile* file, outputStream* stream, size_t scale);

  const GrowableArrayCHeap<MemoryFile*, mtNMT>& files();

  class Instance : public AllStatic {
    static Deferred<MemoryFileTracker> _tracker;

  public:

    static bool initialize(NMT_TrackingLevel tracking_level);

    static MemoryFile* make_file(const char* descriptive_name);
    static void free_file(MemoryFile* device);

    static void allocate_memory(MemoryFile* device, size_t offset, size_t size,
                                const NativeCallStack& stack, MemTag mem_tag);
    static void free_memory(MemoryFile* device, size_t offset, size_t size);

    template<typename F>
    static void iterate_summary(F f) {
      _tracker->iterate_summary(f);
    };

    static void summary_snapshot(VirtualMemorySnapshot* snapshot);

    static void print_report_on(const MemoryFile* device, outputStream* stream, size_t scale);
    static void print_all_reports_on(outputStream* stream, size_t scale);

    static const GrowableArrayCHeap<MemoryFile*, mtNMT>& files();
  };
};

#endif // SHARE_NMT_MEMORYFILETRACKER_HPP