.. _program_listing_file_include_common_metadata.hpp:

Program Listing for File metadata.hpp
=====================================

|exhale_lsh| :ref:`Return to documentation for file <file_include_common_metadata.hpp>` (``include/common/metadata.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   /*
     Copyright 2018-2025, Barcelona Supercomputing Center (BSC), Spain
     Copyright 2015-2025, Johannes Gutenberg Universitaet Mainz, Germany
   
     This software was partially supported by the
     EC H2020 funded project NEXTGenIO (Project ID: 671951, www.nextgenio.eu).
   
     This software was partially supported by the
     ADA-FS project under the SPPEXA project funded by the DFG.
   
     This software was partially supported by the
     the European Union’s Horizon 2020 JTI-EuroHPC research and
     innovation programme, by the project ADMIRE (Project ID: 956748,
     admire-eurohpc.eu)
   
     This project was partially promoted by the Ministry for Digital Transformation
     and the Civil Service, within the framework of the Recovery,
     Transformation and Resilience Plan - Funded by the European Union
     -NextGenerationEU.
   
     This file is part of GekkoFS.
   
     GekkoFS is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation, either version 3 of the License, or
     (at your option) any later version.
   
     GekkoFS 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 for more details.
   
     You should have received a copy of the GNU General Public License
     along with GekkoFS.  If not, see <https://www.gnu.org/licenses/>.
   
     SPDX-License-Identifier: GPL-3.0-or-later
   */
   
   #ifndef FS_METADATA_H
   #define FS_METADATA_H
   #pragma once
   
   
   #include <config.hpp>
   #include <sys/types.h>
   #include <sys/stat.h>
   #include <string>
   #include <cstdint>
   
   namespace gkfs::metadata {
   
   constexpr mode_t LINK_MODE = ((S_IRWXU | S_IRWXG | S_IRWXO) | S_IFLNK);
   
   uint16_t
   gen_unique_id(const std::string& path);
   
   class Metadata {
   private:
       time_t atime_{}; // access time. gets updated on file access unless mounted
                        // with noatime
       time_t mtime_{}; // modify time. gets updated when file content is modified.
       time_t ctime_{}; // change time. gets updated when the file attributes are
                        // changed AND when file content is modified.
       mode_t mode_{};
       nlink_t link_count_{}; // number of names for this inode (hardlinks)
       size_t size_{};     // size_ in bytes, might be computed instead of stored
       blkcnt_t blocks_{}; // allocated file system blocks_
   #ifdef HAS_SYMLINKS
       std::string target_path_; // For links this is the path of the target file
   #ifdef HAS_RENAME
       std::string rename_path_; // In some cases fd is maintained so we need the
                                 // renamed path
   #endif
   #endif
   
       void
       init_time();
   
   public:
       Metadata() = default;
   
       explicit Metadata(mode_t mode);
   
   #ifdef HAS_SYMLINKS
   
       Metadata(mode_t mode, const std::string& target_path);
   
   #endif
   
       // Construct from a binary representation of the object
       explicit Metadata(const std::string& binary_str);
   
       std::string
       serialize() const;
   
       // currently unused
       void
       update_atime_now();
   
       void
       update_mtime_now();
   
       // Getter and Setter
       time_t
       atime() const;
   
       void
       atime(time_t atime_);
   
       time_t
       mtime() const;
   
       void
       mtime(time_t mtime_);
   
       time_t
       ctime() const;
   
       void
       ctime(time_t ctime_);
   
       mode_t
       mode() const;
   
       void
       mode(mode_t mode_);
   
       nlink_t
       link_count() const;
   
       void
       link_count(nlink_t link_count_);
   
       size_t
       size() const;
   
       void
       size(size_t size_);
   
       blkcnt_t
       blocks() const;
   
       void
       blocks(blkcnt_t blocks_);
   
   #ifdef HAS_SYMLINKS
   
       std::string
       target_path() const;
   
       void
       target_path(const std::string& target_path);
   
       bool
       is_link() const;
   
   #ifdef HAS_RENAME
       std::string
       rename_path() const;
   
       void
       rename_path(const std::string& rename_path);
   #endif // HAS_RENAME
   
   #endif // HAS_SYMLINKS
   };
   
   } // namespace gkfs::metadata
   
   
   #endif // FS_METADATA_H