fatfs.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_FATFS_FATFS_H
#define CYGONCE_FATFS_FATFS_H
//==========================================================================
//
//      fatfs.h
//
//      FAT file system header 
//
//==========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 2003 Savin Zlobec 
//
// 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.
//
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):           savin
// Date:                2003-06-29
//
//####DESCRIPTIONEND####
//
//==========================================================================

#include "cyg_type.h"
#include "io.h"
#include "types.h"
#include "stat.h"
#include "codes.h"
#include "dirent.h"
#include "string.h"
#include "fileio.h"

// --------------------------------------------------------------------------

#define FATFS_HASH_TABLE_SIZE									32 

#define FATFS_NODE_ALLOC_THRESHOLD								16 

#define FATFS_FAT_TABLE_CACHE_INCREMENT							1 

#ifdef CYGDBG_FS_FAT_NODE_CACHE_EXTRA_CHECKS
# define FATFS_NODE_CACHE_EXTRA_CHECKS 1
#endif

// --------------------------------------------------------------------------

// Node cache tracing support
//#define FATFS_TRACE_NODE_CACHE 1

// FAT table cache tracing support
//#define FATFS_TRACE_FAT_TABLE_CACHE 1

// FAT table operations tracing support 
//#define FATFS_TRACE_FAT_TABLE 1

// FAT dir entry operations tracing support 
//#define FATFS_TRACE_DIR_ENTRY 1

// FAT clusters operations tracing support 
//#define FATFS_TRACE_CLUSTER 1

// FAT data tracing support 
//#define FATFS_TRACE_DATA 1

// FAT file operations tracing support 
//#define FATFS_TRACE_FILE_OP 1

// FAT filesystem operations tracing support 
//#define FATFS_TRACE_FS_OP 1

// --------------------------------------------------------------------------

typedef enum fatfs_type_e
{
    FATFS_FAT12 = 0,    
    FATFS_FAT16         
} fatfs_type_t;

typedef struct fatfs_data_pos_s
{
    cyg_uint32 cluster;      // Cluster number
    cyg_uint32 cluster_snum; // Cluster file seq number 
                             // (0 - first cluster of file,
                             //  1 - second cluster of file, ...)  
    cyg_uint32 cluster_pos;  // Position inside cluster
} fatfs_data_pos_t;

typedef struct fatfs_tcache_s
{
    cyg_uint32 *clusters; // Cached clusters array
    cyg_uint32  size;     // Number of cached clusters in array
    cyg_uint32  max_size; // Size of array (allocated space)
} fatfs_tcache_t;

typedef struct fatfs_node_s
{
    char                 filename[12+1]; // File name
    mode_t               mode;           // Node type
    cyg_ucount32         refcnt;         // Open file/current dir references
    size_t               size;           // Size of file in bytes
    time_t               ctime;          // Creation timestamp
    time_t               atime;          // Last access timestamp
    time_t               mtime;          // Last write timestamp
    cyg_uint8            priv_data;      // Private data
    cyg_uint32           cluster;        // First cluster number
    cyg_uint32           parent_cluster; // First cluster of parent dentry
    fatfs_data_pos_t     dentry_pos;     // Position of node's dir entry on disk

    struct fatfs_node_s *list_prev;      // Next node in list
    struct fatfs_node_s *list_next;      // Prev node in list
    struct fatfs_node_s *hash_next;      // Next node in hash

    fatfs_tcache_t       tcache;         // Node FAT table clusters cache 
} fatfs_node_t;

typedef struct fatfs_hash_table_s 
{
    cyg_uint32     size;                         // Number of slots
    cyg_uint32     n;                            // Number of nodes 
    fatfs_node_t  *nodes[FATFS_HASH_TABLE_SIZE]; // Nodes slots
} fatfs_hash_table_t;

typedef struct fatfs_node_list_s
{
    cyg_uint32    size;          // Number of nodes in list
    fatfs_node_t *first;         // First node in list
    fatfs_node_t *last;          // Last node in list
} fatfs_node_list_t;

typedef struct fatfs_disk_s
{
    cyg_uint32   sector_size;        // Sector size in bytes
    cyg_uint32   sector_size_log2;   // Sector size log2
    cyg_uint32   cluster_size;       // Cluster size in bytes
    cyg_uint32   cluster_size_log2;  // Cluster size log2 
    cyg_uint32   fat_tbl_pos;        // Position of the first FAT table
    cyg_uint32   fat_tbl_size;       // FAT table size in bytes
    cyg_uint32   fat_tbl_nents;      // Number of entries in FAT table
    cyg_uint32   fat_tbls_num;       // Number of FAT tables
    cyg_uint32   fat_root_dir_pos;   // Position of the root dir
    cyg_uint32   fat_root_dir_size;  // Root dir size in bytes 
    cyg_uint32   fat_root_dir_nents; // Max number of entries in root dir
    cyg_uint32   fat_data_pos;       // Position of data area
    fatfs_type_t fat_type;           // Type of FAT - 12 or 16
    
    cyg_io_handle_t  dev_h;          // Disk device handle
    fatfs_node_t    *root;           // Root dir node

    fatfs_node_list_t  live_nlist;   // List of nodes with refcnt > 0
    fatfs_node_list_t  dead_nlist;   // List of nodes with refcnt == 0
    fatfs_hash_table_t node_hash;    // Hash of nodes in live and dead lists
} fatfs_disk_t;

// --------------------------------------------------------------------------

int  fatfs_get_disk_info(fatfs_disk_t *disk);

void fatfs_get_root_node(fatfs_disk_t *disk, fatfs_node_t *root);

bool fatfs_is_node_root_node(fatfs_node_t *node);

int  fatfs_get_dir_entry_node(fatfs_disk_t *disk,
                              fatfs_node_t *dir,
                              cyg_uint32   *pos,
                              fatfs_node_t *node);

int  fatfs_write_file_attr(fatfs_disk_t *disk, fatfs_node_t *node);

int  fatfs_delete_file(fatfs_disk_t *disk, fatfs_node_t *node);

int  fatfs_create_file(fatfs_disk_t *disk, 
                       fatfs_node_t *dir, 
                       const char   *name,
                       int           namelen,
                       fatfs_node_t *node);

int  fatfs_create_dir(fatfs_disk_t *disk, 
                      fatfs_node_t *dir, 
                      const char   *name,
                      int           namelen,
                      fatfs_node_t *node);

int  fatfs_trunc_file(fatfs_disk_t *disk, fatfs_node_t *node);

int  fatfs_rename_file(fatfs_disk_t *disk, 
                       fatfs_node_t *dir1,
                       fatfs_node_t *node,
                       fatfs_node_t *dir2,
                       const char   *name,
                       int           namelen);

int  fatfs_read_data(fatfs_disk_t *disk,
                     fatfs_node_t *node,
                     void         *data,
                     cyg_uint32   *len,
                     cyg_uint32    off);

int  fatfs_write_data(fatfs_disk_t *disk,
                      fatfs_node_t *node,
                      void         *data,
                      cyg_uint32   *len,
                      cyg_uint32    off);

// --------------------------------------------------------------------------

void fatfs_node_cache_init(fatfs_disk_t *disk);

void fatfs_node_cache_flush(fatfs_disk_t *disk);

fatfs_node_t *fatfs_node_alloc(fatfs_disk_t *disk, fatfs_node_t *node_data);

void fatfs_node_ref(fatfs_disk_t *disk, fatfs_node_t *node);

void fatfs_node_unref(fatfs_disk_t *disk, fatfs_node_t *node);

void fatfs_node_touch(fatfs_disk_t *disk, fatfs_node_t *node);

void fatfs_node_rehash(fatfs_disk_t *disk, fatfs_node_t *node);

void fatfs_node_free(fatfs_disk_t *disk, fatfs_node_t *node);

fatfs_node_t* fatfs_node_find(fatfs_disk_t *disk, 
                              const char   *name, 
                              unsigned int  namelen, 
                              cyg_uint32    parent_cluster);

int  fatfs_get_live_node_count(fatfs_disk_t *disk);

int  fatfs_get_dead_node_count(fatfs_disk_t *disk);

void fatfs_node_flush_dead_tcache(fatfs_disk_t *disk);

// --------------------------------------------------------------------------

int  fatfs_tcache_create(fatfs_disk_t *disk, cyg_uint32 mem_size);

void fatfs_tcache_delete(fatfs_disk_t *disk);

void fatfs_tcache_init(fatfs_disk_t *disk, fatfs_tcache_t *tcache);

void fatfs_tcache_flush(fatfs_disk_t *disk, fatfs_tcache_t *tcache);

bool fatfs_tcache_get(fatfs_disk_t   *disk,
                      fatfs_tcache_t *tcache, 
                      cyg_uint32      num, 
                      cyg_uint32     *cluster);

bool fatfs_tcache_get_last(fatfs_disk_t   *disk,
                           fatfs_tcache_t *tcache, 
                           cyg_uint32     *num, 
                           cyg_uint32     *cluster);

bool fatfs_tcache_set(fatfs_disk_t   *disk,
                      fatfs_tcache_t *tcache, 
                      cyg_uint32      num, 
                      cyg_uint32      cluster);

// --------------------------------------------------------------------------
// Support routines
// These enable the definition of local versions of certain routines
// if the given packages are not present.

#ifndef CYGPKG_LIBC_I18N

__externC int toupper( int c );

#endif

#ifndef CYGFUN_LIBC_STRING_BSD_FUNCS

__externC int strcasecmp( const char *s1, const char *s2 );

__externC int strncasecmp( const char *s1, const char *s2, size_t n );

#endif

// --------------------------------------------------------------------------

#endif // CYGONCE_FATFS_FATFS_H

// --------------------------------------------------------------------------
// EOF fatfs.h