mariadb-columnstore-engine/utils/idbdatafile/IDBFileSystem.h

/* Copyright (C) 2014 InfiniDB, Inc.

   This program 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; version 2 of
   the License.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301, USA. */

#ifndef IDBFILESYSTEM_H_
#define IDBFILESYSTEM_H_

#include <sys/types.h>
#include <list>
#include "IDBDataFile.h"
#include "IDBFactory.h"

namespace idbdatafile
{

/**
 * IDBFileSystem is a combination abstract base class and factory. The
 * purpose is to encapsulate access to various file system functions
 * across different file system types including hdfs.
 */
class IDBFileSystem
{
public:
    /**
     * The TYPE enum defines the supported underlying filesystem types
     */
    enum Types
    {
        UNKNOWN = 0x00,
        POSIX = 0x0001,
        HDFS  = 0x0002,
        CLOUD = 0x0003
    };

    /**
     * Destructor
     */
    virtual ~IDBFileSystem();

    /**
     * getFs() returns a reference to the IDBFileSystem instance for the
     * specified type
     */
    static IDBFileSystem& getFs(IDBDataFile::Types type);

    /**
     * mkdir() creates a directory specified by pathname including any
     * parent directories if needed.
     * Returns 0 on success, -1 on error
     */
    virtual int mkdir(const char* pathname) = 0;

    /**
     * remove() removes a path from the filesystem.  It will handle
     * both files and directories (including non-empty directories).  Note
     * that a call to remove of a path that does not exist will return as
     * success.
     *
     * Returns 0 on success, -1 on error
     */
    virtual int remove(const char* pathname) = 0;

    /**
     * rename() names a file, moving it between directories if required.
     * Returns 0 on success, -1 on error
     */
    virtual int rename(const char* oldpath, const char* newpath) = 0;

    /**
     * size() returns the size of the file specified by path.
     * Returns the size on success, -1 on error
     */
    virtual off64_t size(const char* path) const = 0;

    /**
     * compressedSize() returns the decompressed size of the file
     * speicified by path.
     * Returns the size on success, -1 on error
     */
    virtual off64_t compressedSize(const char* path) const = 0;

    /**
     * exists() checks for the existence of a particular path.
     * Returns true if exists, false otherwise.
     */
    virtual bool exists(const char* pathname) const = 0;

    /**
     * listDirectory() returns the contents of the directory as a
     * list of strings.  For now, no indication of whether each
     * item is a file or directory - both files and subdirectories
     * will be returned.
     * Returns 0 on success.  -1 on error (incl if directory does
     * not exist.
     */

    virtual int listDirectory(const char* pathname, std::list<std::string>& contents) const = 0;

    /**
     * isDir() returns whether or not the path is a directory
     */
    virtual bool isDir(const char* pathname) const = 0;

    /**
     * copyfile() copies the source file to the destination file
     * Returns 0 on success.  -1 on error.
     */
    virtual int copyFile(const char* srcPath, const char* destPath) const = 0;

    /**
     * isFsUp() checks if the filesystem is up
     * Returns 0 on success.  -1 on error.
     */
    virtual bool filesystemIsUp() const
    {
        return true;
    }

    virtual bool filesystemSync() const
    {
        return true;
    }

    /**
     * chown() changes the owner of the object on the FS
     * Returns 0 on success.  -1 on error.
     */
    virtual int chown(const char* objectName,
                      const uid_t p_uid,
                      const gid_t p_pid,
                      int& funcErrno) const
    {
        return 0;
    }


protected:
    IDBFileSystem( Types type );

private:
    Types m_type;
};

/**
 * getFs() returns a reference to the IDBFileSystem instance for the
 * specified type
 */
inline
IDBFileSystem& IDBFileSystem::getFs(IDBDataFile::Types type)
{
    return IDBFactory::getFs(type);
}

}

#endif /* IDBFILESYSTEM_H_ */