fileio.h

该工程是从ecos嵌入式系统下移植过来的一个小型的fat16文件系统

#ifndef CYGONCE_FILEIO_H
#define CYGONCE_FILEIO_H
//=============================================================================
//
//      fileio.h
//
//      Fileio header
//
//=============================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
//
// eCos 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.
//
// eCos 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 eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
// at http://sources.redhat.com/ecos/ecos-license/
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//=============================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):     nickg
// Contributors:  nickg
// Date:          2000-05-25
// Purpose:       Fileio header
// Description:   This header contains the external definitions of the general file
//                IO subsystem for POSIX and EL/IX compatability.
//              
// Usage:
//              #include <fileio.h>
//              ...
//              
//
//####DESCRIPTIONEND####
//
//=============================================================================

//#include <pkgconf/hal.h>
//#include <pkgconf/io_fileio.h>

#include "cyg_type.h"
//#include <cyg/hal/hal_tables.h>

#include <stddef.h>             // NULL, size_t
//#include <limits.h>
#include "systypes.h"
//#include <fcntl.h>
#include "stat.h"

//=============================================================================
// forward definitions

struct cyg_mtab_entry;
typedef struct cyg_mtab_entry cyg_mtab_entry;

struct  cyg_fstab_entry;
typedef struct  cyg_fstab_entry  cyg_fstab_entry;

struct CYG_FILEOPS_TAG;
typedef struct CYG_FILEOPS_TAG cyg_fileops;

struct CYG_FILE_TAG;
typedef struct CYG_FILE_TAG cyg_file;

struct CYG_IOVEC_TAG;
typedef struct CYG_IOVEC_TAG cyg_iovec;

struct CYG_UIO_TAG;
typedef struct CYG_UIO_TAG cyg_uio;

struct CYG_SELINFO_TAG;
typedef struct CYG_SELINFO_TAG cyg_selinfo;

//=============================================================================
// Directory pointer

typedef CYG_ADDRWORD cyg_dir;

#define CYG_DIR_NULL 0

//=============================================================================
// Filesystem table entry

typedef int     cyg_fsop_mount    ( cyg_fstab_entry *fste, cyg_mtab_entry *mte );
typedef int     cyg_fsop_umount   ( cyg_mtab_entry *mte );
typedef int     cyg_fsop_open     ( cyg_mtab_entry *mte, cyg_dir dir, const char *name,
                                    int mode,  cyg_file *fte );
typedef int     cyg_fsop_unlink   ( cyg_mtab_entry *mte, cyg_dir dir, const char *name );
typedef int     cyg_fsop_mkdir    ( cyg_mtab_entry *mte, cyg_dir dir, const char *name );
typedef int     cyg_fsop_rmdir    ( cyg_mtab_entry *mte, cyg_dir dir, const char *name );
typedef int     cyg_fsop_rename   ( cyg_mtab_entry *mte, cyg_dir dir1, const char *name1,
                                    cyg_dir dir2, const char *name2 );
typedef int     cyg_fsop_link     ( cyg_mtab_entry *mte, cyg_dir dir1, const char *name1,
                                    cyg_dir dir2, const char *name2, int type );
typedef int     cyg_fsop_opendir  ( cyg_mtab_entry *mte, cyg_dir dir, const char *name,
                                    cyg_file *fte );
typedef int     cyg_fsop_chdir    ( cyg_mtab_entry *mte, cyg_dir dir, const char *name,
                                    cyg_dir *dir_out );
typedef int     cyg_fsop_stat     ( cyg_mtab_entry *mte, cyg_dir dir, const char *name,
                                    struct stat *buf);
typedef int     cyg_fsop_getinfo  ( cyg_mtab_entry *mte, cyg_dir dir, const char *name,
                                    int key, void *buf, int len );
typedef int     cyg_fsop_setinfo  ( cyg_mtab_entry *mte, cyg_dir dir, const char *name,
                                    int key, void *buf, int len );


struct cyg_fstab_entry
{
    const char          *name;          // filesystem name
    CYG_ADDRWORD        data;           // private data value
    cyg_uint32          syncmode;       // synchronization mode
    
    cyg_fsop_mount      *mount;
    cyg_fsop_umount     *umount;
    cyg_fsop_open       *open;
    cyg_fsop_unlink     *unlink;
    cyg_fsop_mkdir      *mkdir;
    cyg_fsop_rmdir      *rmdir;
    cyg_fsop_rename     *rename;
    cyg_fsop_link       *link;
    cyg_fsop_opendir    *opendir;
    cyg_fsop_chdir      *chdir;
    cyg_fsop_stat       *stat;
    cyg_fsop_getinfo    *getinfo;
    cyg_fsop_setinfo    *setinfo;
} CYG_HAL_TABLE_TYPE;

//-----------------------------------------------------------------------------
// Keys for getinfo() and setinfo()

#define FS_INFO_CONF            1       /* pathconf() */
#define FS_INFO_ACCESS          2       /* access() */
#define FS_INFO_GETCWD          3       /* getcwd() */

//-----------------------------------------------------------------------------
// Types for link()

#define CYG_FSLINK_HARD         1       /* form a hard link */
#define CYG_FSLINK_SOFT         2       /* form a soft link */

//-----------------------------------------------------------------------------
// getinfo() and setinfo() buffers structures.

struct cyg_getcwd_info
{
    char        *buf;           /* buffer for cwd string */
    size_t      size;           /* size of buffer */
};

//-----------------------------------------------------------------------------
// Macro to define an initialized fstab entry

#define FSTAB_ENTRY( _l, _name, _data, _syncmode, _mount, _umount,      \
                     _open, _unlink,  _mkdir, _rmdir, _rename, _link,   \
                     _opendir, _chdir, _stat, _getinfo, _setinfo)       \
struct cyg_fstab_entry  _l =                  \
{                                                                       \
    _name,                                                              \
    _data,                                                              \
    _syncmode,                                                          \
    _mount,                                                             \
    _umount,                                                            \
    _open,                                                              \
    _unlink,                                                            \
    _mkdir,                                                             \
    _rmdir,                                                             \
    _rename,                                                            \
    _link,                                                              \
    _opendir,                                                           \
    _chdir,                                                             \
    _stat,                                                              \
    _getinfo,                                                           \
    _setinfo                                                            \
};

//=============================================================================
// Mount table entry

struct cyg_mtab_entry
{
    const char          *name;          // name of mount point
    const char          *fsname;        // name of implementing filesystem
    const char          *devname;       // name of hardware device
    CYG_ADDRWORD        data;           // private data value，用来存放了sb
    
    // The following are filled in after a successful mount operation
    cyg_bool            valid;          // Valid entry?
    cyg_fstab_entry     *fs;            // pointer to fstab entry
    cyg_dir             root;           // root directory pointer
} /*CYG_HAL_TABLE_TYPE*/;


// This macro defines an initialized mtab entry

#define MTAB_ENTRY( _l, _name, _fsname, _devname, _data )       \
struct cyg_mtab_entry _l CYG_HAL_TABLE_ENTRY(mtab) =            \
{                                                               \