mfile.h

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/* This file is part of the Zebra server.
   Copyright (C) Index Data
 
Zebra 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 2, or (at your option) any later
version.
 
Zebra 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 St, Fifth Floor, Boston, MA  02110-1301  USA
 
*/
 
#ifndef MFILE_H
#define MFILE_H
 
#include <stdio.h>
#include <yaz/yconfig.h>
#include <idzebra/version.h>
#include <idzebra/util.h>
 
#ifdef WIN32
 
/* 64-bit access .. */
typedef __int64 mfile_off_t;
#define mfile_seek _lseeki64
 
#else
#include <sys/types.h>
typedef off_t mfile_off_t;
#define mfile_seek lseek
#endif
 
#ifndef FILENAME_MAX
#include <sys/param.h>
#define FILENAME_MAX MAXPATHLEN
#endif
 
#include <zebra-lock.h>
 
YAZ_BEGIN_CDECL
 
#define MF_MIN_BLOCKS_CREAT 1          /* minimum free blocks in new dir */
#define MF_MAX_PARTS 28                 /* max # of part-files per metafile */
 
#define mf_blocksize(mf) ((mf)->blocksize)
 
 
typedef struct mf_dir
{
    char name[FILENAME_MAX+1];
    mfile_off_t max_bytes;      /* allocated bytes in this dir. */
    mfile_off_t avail_bytes;    /* bytes left */
    struct mf_dir *next;
} mf_dir;
 
typedef struct part_file
{
    zint number;
    zint top;
    zint blocks;
    mfile_off_t bytes;
    mf_dir *dir;
    char *path;
    int fd;
} part_file;
 
struct MFile_area_struct;
typedef struct MFile_area_struct *MFile_area;
 
typedef struct meta_file
{
    char name[FILENAME_MAX+1];
    part_file files[MF_MAX_PARTS];
    int no_files;
    int cur_file;
    int open;                          /* is this file open? */
    int blocksize;
    mfile_off_t min_bytes_creat;  /* minimum bytes required to enter directory */
    MFile_area ma;
    int wr;
    Zebra_mutex mutex;
 
    struct meta_file *next;
} *MFile, meta_file;
 
struct MFile_area_struct
{
    char name[FILENAME_MAX+1];
    mf_dir *dirs;
    struct meta_file *mfiles;
    struct MFile_area_struct *next;  /* global list of active areas */
    Zebra_mutex mutex;
};
 
MFile_area mf_init(const char *name, const char *spec, const char *base,
                   int only_shadow_files)
    ZEBRA_GCC_ATTR((warn_unused_result));
 
void mf_destroy(MFile_area ma);
 
MFile mf_open(MFile_area ma, const char *name, int block_size, int wflag)
    ZEBRA_GCC_ATTR((warn_unused_result));
 
int mf_close(MFile mf);
 
int mf_read(MFile mf, zint no, int offset, int nbytes, void *buf)
    ZEBRA_GCC_ATTR((warn_unused_result));
 
int mf_write(MFile mf, zint no, int offset, int nbytes, const void *buf)
    ZEBRA_GCC_ATTR((warn_unused_result));
 
void mf_reset(MFile_area ma, int unlink_flag);
 
/* \brief gets statistics about directory in metafile area
   \param ma the area
   \param no directory number (0=first, 1=second,...)
   \param directory holds directory name (if found)
   \param used_bytes used file bytes in directory (if found)
   \param max_bytes max usage of bytes (if found)
   \retval 1 no is within range and directory, used, max are set.
   \retval 0 no is out of range and directory, used, max are unset
 
   We are using double, because off_t may have a different size
   on same platform depending on whether 64-bit is enabled or not.
   Note that if an area has unlimited size, that is represented
   as max_bytes = -1.
*/
int mf_area_directory_stat(MFile_area ma, int no, const char **directory,
                           double *bytes_used, double *bytes_max);
 
YAZ_END_CDECL
 
#endif
/*
 * Local variables:
 * c-basic-offset: 4
 * c-file-style: "Stroustrup"
 * indent-tabs-mode: nil
 * End:
 * vim: shiftwidth=4 tabstop=8 expandtab
 */