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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2002 by Linus Nielsen Feltzing
*
* 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; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef FAT_H
#define FAT_H
#include <stdbool.h>
#include <sys/types.h>
#include <time.h>
#include "config.h"
#include "system.h"
#include "mv.h" /* for volume definitions */
/********
**** DO NOT use these functions directly unless otherwise noted. Required
**** synchronization is done by higher-level interfaces to minimize locking
**** overhead.
****
**** Volume, drive, string, etc. parameters should also be checked by
**** callers for gross violations-- NULL strings, out-of-bounds values,
**** etc.
****/
/****************************************************************************
** Values that can be overridden by a target in config-[target].h
**/
/* if your ATA implementation can do better, go right ahead and increase this
* value */
#ifndef FAT_MAX_TRANSFER_SIZE
#define FAT_MAX_TRANSFER_SIZE 256
#endif
/* still experimental? */
/* increasing this will increase the total memory used by the cache; the
cache, as noted in disk_cache.h, has other minimum requirements that may
prevent reducing its number of entries in order to compensate */
#ifndef SECTOR_SIZE
#define SECTOR_SIZE 512
#endif
/**
****************************************************************************/
#define INVALID_SECNUM (0xfffffffeul) /* sequential, not FAT */
#define FAT_MAX_FILE_SIZE (0xfffffffful) /* 2^32-1 bytes */
#define MAX_DIRENTRIES 65536
#define MAX_DIRECTORY_SIZE (MAX_DIRENTRIES*32) /* 2MB max size */
/* these aren't I/O error conditions, so define specially; failure rc's
* shouldn't return the last digit as "0", therefore this is unambiguous */
#define FAT_RC_ENOSPC (-10)
#define FAT_SEEK_EOF (-20)
/* Number of bytes reserved for a file name (including the trailing \0).
Since names are stored in the entry as UTF-8, we won't be ble to
store all names allowed by FAT. In FAT, a name can have max 255
characters (not bytes!). Since the UTF-8 encoding of a char may take
up to 4 bytes, there will be names that we won't be able to store
completely. For such names, the short DOS name is used. */
#define FAT_DIRENTRY_NAME_MAX 255
struct fat_direntry
{
union {
uint8_t name[255+1+4]; /* UTF-8 name plus \0 plus parse slop */
uint16_t ucssegs[5+20][13]; /* UTF-16 segment buffer - layout saves... */
}; /* ...130 bytes (important if stacked) */
uint16_t ucsterm; /* allow one NULL-term after ucssegs */
uint8_t shortname[13]; /* DOS filename (OEM charset) */
uint8_t attr; /* file attributes */
uint8_t crttimetenth; /* millisecond creation time stamp (0-199) */
uint16_t crttime; /* creation time */
uint16_t crtdate; /* creation date */
uint16_t lstaccdate; /* last access date */
uint16_t wrttime; /* last write time */
uint16_t wrtdate; /* last write date */
uint32_t filesize; /* file size in bytes */
int32_t firstcluster; /* first FAT cluster of file, 0 if empty */
};
/* cursor structure used for scanning directories; holds the last-returned
entry information */
struct fat_dirscan_info
{
unsigned int entry; /* short dir entry index in parent */
unsigned int entries; /* number of dir entries used */
};
#define FAT_RW_VAL (0u - 1)
/* basic FAT file information about where to find a file and who houses it */
struct fat_file
{
#ifdef HAVE_MULTIVOLUME
int volume; /* file resides on which volume (first!) */
#endif
long firstcluster; /* first cluster in file */
long dircluster; /* first cluster of parent directory */
struct fat_dirscan_info e; /* entry information */
};
/* this stores what was last accessed when read or writing a file's data */
struct fat_filestr
{
struct fat_file *fatfilep; /* common file information */
long lastcluster; /* cluster of last access */
unsigned long lastsector; /* sector of last access */
long clusternum; /* cluster number of last access */
unsigned long sectornum; /* sector number within current cluster */
bool eof; /* end-of-file reached */
};
/** File entity functions **/
int fat_create_file(struct fat_file *parent, const char *name,
uint8_t attr, struct fat_file *file,
struct fat_direntry *fatent);
bool fat_dir_is_parent(const struct fat_file *dir, const struct fat_file *file);
bool fat_file_is_same(const struct fat_file *file1, const struct fat_file *file2);
int fat_fstat(struct fat_file *file, struct fat_direntry *entry);
int fat_open(const struct fat_file *parent, long startcluster,
struct fat_file *file);
int fat_open_rootdir(IF_MV(int volume,) struct fat_file *dir);
enum fat_remove_op /* what should fat_remove(), remove? */
{
FAT_RM_DIRENTRIES = 0x1, /* remove only directory entries */
FAT_RM_DATA = 0x2, /* remove only file data */
FAT_RM_ALL = 0x3, /* remove all of above */
};
int fat_remove(struct fat_file *file, enum fat_remove_op what);
int fat_rename(struct fat_file *parent, struct fat_file *file,
const unsigned char *newname);
/** File stream functions **/
int fat_closewrite(struct fat_filestr *filestr, uint32_t size,
struct fat_direntry *fatentp);
void fat_filestr_init(struct fat_filestr *filestr, struct fat_file *file);
unsigned long fat_query_sectornum(const struct fat_filestr *filestr);
long fat_readwrite(struct fat_filestr *filestr, unsigned long sectorcount,
void *buf, bool write);
void fat_rewind(struct fat_filestr *filestr);
int fat_seek(struct fat_filestr *filestr, unsigned long sector);
int fat_truncate(const struct fat_filestr *filestr);
/** Directory stream functions **/
struct filestr_cache;
int fat_readdir(struct fat_filestr *dirstr, struct fat_dirscan_info *scan,
struct filestr_cache *cachep, struct fat_direntry *entry);
void fat_rewinddir(struct fat_dirscan_info *scan);
/** Mounting and unmounting functions **/
bool fat_ismounted(IF_MV_NONVOID(int volume));
int fat_mount(IF_MV(int volume,) IF_MD(int drive,) unsigned long startsector);
int fat_unmount(IF_MV_NONVOID(int volume));
/** Debug screen stuff **/
#ifdef MAX_LOG_SECTOR_SIZE
int fat_get_bytes_per_sector(IF_MV_NONVOID(int volume));
#endif /* MAX_LOG_SECTOR_SIZE */
unsigned int fat_get_cluster_size(IF_MV_NONVOID(int volume));
void fat_recalc_free(IF_MV_NONVOID(int volume));
bool fat_size(IF_MV(int volume,) unsigned long *size, unsigned long *free);
/** Misc. **/
time_t fattime_mktime(uint16_t fatdate, uint16_t fattime);
void fat_empty_fat_direntry(struct fat_direntry *entry);
void fat_init(void);
#endif /* FAT_H */
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