rockbox/firmware/drivers/fat.c
Linus Nielsen Feltzing 0185ee7e4c Removed nasty lvalue cast
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@4934 a1c6a512-1295-4272-9138-f99709370657
2004-07-24 17:20:21 +00:00

2001 lines
60 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2002 by Linus Nielsen Feltzing
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <ctype.h>
#include <stdbool.h>
#include "fat.h"
#include "ata.h"
#include "debug.h"
#include "panic.h"
#include "system.h"
#include "timefuncs.h"
#define BYTES2INT16(array,pos) \
(array[pos] | (array[pos+1] << 8 ))
#define BYTES2INT32(array,pos) \
(array[pos] | (array[pos+1] << 8 ) | \
(array[pos+2] << 16 ) | (array[pos+3] << 24 ))
#define FATTYPE_FAT12 0
#define FATTYPE_FAT16 1
#define FATTYPE_FAT32 2
/* BPB offsets; generic */
#define BS_JMPBOOT 0
#define BS_OEMNAME 3
#define BPB_BYTSPERSEC 11
#define BPB_SECPERCLUS 13
#define BPB_RSVDSECCNT 14
#define BPB_NUMFATS 16
#define BPB_ROOTENTCNT 17
#define BPB_TOTSEC16 19
#define BPB_MEDIA 21
#define BPB_FATSZ16 22
#define BPB_SECPERTRK 24
#define BPB_NUMHEADS 26
#define BPB_HIDDSEC 28
#define BPB_TOTSEC32 32
/* fat12/16 */
#define BS_DRVNUM 36
#define BS_RESERVED1 37
#define BS_BOOTSIG 38
#define BS_VOLID 39
#define BS_VOLLAB 43
#define BS_FILSYSTYPE 54
/* fat32 */
#define BPB_FATSZ32 36
#define BPB_EXTFLAGS 40
#define BPB_FSVER 42
#define BPB_ROOTCLUS 44
#define BPB_FSINFO 48
#define BPB_BKBOOTSEC 50
#define BS_32_DRVNUM 64
#define BS_32_BOOTSIG 66
#define BS_32_VOLID 67
#define BS_32_VOLLAB 71
#define BS_32_FILSYSTYPE 82
#define BPB_LAST_WORD 510
/* attributes */
#define FAT_ATTR_LONG_NAME (FAT_ATTR_READ_ONLY | FAT_ATTR_HIDDEN | \
FAT_ATTR_SYSTEM | FAT_ATTR_VOLUME_ID)
#define FAT_ATTR_LONG_NAME_MASK (FAT_ATTR_READ_ONLY | FAT_ATTR_HIDDEN | \
FAT_ATTR_SYSTEM | FAT_ATTR_VOLUME_ID | \
FAT_ATTR_DIRECTORY | FAT_ATTR_ARCHIVE )
#define FATDIR_NAME 0
#define FATDIR_ATTR 11
#define FATDIR_NTRES 12
#define FATDIR_CRTTIMETENTH 13
#define FATDIR_CRTTIME 14
#define FATDIR_CRTDATE 16
#define FATDIR_LSTACCDATE 18
#define FATDIR_FSTCLUSHI 20
#define FATDIR_WRTTIME 22
#define FATDIR_WRTDATE 24
#define FATDIR_FSTCLUSLO 26
#define FATDIR_FILESIZE 28
#define FATLONG_ORDER 0
#define FATLONG_TYPE 12
#define FATLONG_CHKSUM 13
#define CLUSTERS_PER_FAT_SECTOR (SECTOR_SIZE / 4)
#define DIR_ENTRIES_PER_SECTOR (SECTOR_SIZE / DIR_ENTRY_SIZE)
#define DIR_ENTRY_SIZE 32
#define NAME_BYTES_PER_ENTRY 13
#define FAT_BAD_MARK 0x0ffffff7
#define FAT_EOF_MARK 0x0ffffff8
/* filename charset conversion table */
static const unsigned char unicode2iso8859_2[] = {
0x00, 0x00, 0xc3, 0xe3, 0xa1, 0xb1, 0xc6, 0xe6, /* 0x0100 */
0x00, 0x00, 0x00, 0x00, 0xc8, 0xe8, 0xcf, 0xef, /* 0x0108 */
0xd0, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0110 */
0xca, 0xea, 0xcc, 0xec, 0x00, 0x00, 0x00, 0x00, /* 0x0118 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0120 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0128 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0130 */
0x00, 0xc5, 0xe5, 0x00, 0x00, 0xa5, 0xb5, 0x00, /* 0x0138 */
0x00, 0xa3, 0xb3, 0xd1, 0xf1, 0x00, 0x00, 0xd2, /* 0x0140 */
0xf2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0148 */
0xd5, 0xf5, 0x00, 0x00, 0xc0, 0xe0, 0x00, 0x00, /* 0x0150 */
0xd8, 0xf8, 0xa6, 0xb6, 0x00, 0x00, 0xaa, 0xba, /* 0x0158 */
0xa9, 0xb9, 0xde, 0xfe, 0xab, 0xbb, 0x00, 0x00, /* 0x0160 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xd9, 0xf9, /* 0x0168 */
0xdb, 0xfb, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0170 */
0x00, 0xac, 0xbc, 0xaf, 0xbf, 0xae, 0xbe, 0x00, /* 0x0178 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0180 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0188 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0190 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0198 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01a0 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01a8 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01b0 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01b8 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01c0 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01c8 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01d0 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01d8 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01e0 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01e8 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01f0 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x01f8 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0200 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0208 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0210 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0218 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0220 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0228 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0230 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0238 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0240 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0248 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0250 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0258 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0260 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0268 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0270 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0278 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0280 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0288 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0290 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x0298 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x02a0 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x02a8 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x02b0 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x02b8 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xb7, /* 0x02c0 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x02c8 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x02d0 */
0xa2, 0xff, 0x00, 0xb2, 0x00, 0xbd, 0x00, 0x00, /* 0x02d8 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x02e0 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x02e8 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x02f0 */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 /* 0x02f8 */
};
struct fsinfo {
unsigned int freecount; /* last known free cluster count */
unsigned int nextfree; /* first cluster to start looking for free
clusters, or 0xffffffff for no hint */
};
/* fsinfo offsets */
#define FSINFO_FREECOUNT 488
#define FSINFO_NEXTFREE 492
struct bpb
{
char bs_oemname[9]; /* OEM string, ending with \0 */
int bpb_bytspersec; /* Bytes per sectory, typically 512 */
unsigned int bpb_secperclus; /* Sectors per cluster */
int bpb_rsvdseccnt; /* Number of reserved sectors */
int bpb_numfats; /* Number of FAT structures, typically 2 */
int bpb_rootentcnt; /* Number of dir entries in the root */
int bpb_totsec16; /* Number of sectors on the volume (old 16-bit) */
int bpb_media; /* Media type (typically 0xf0 or 0xf8) */
int bpb_fatsz16; /* Number of used sectors per FAT structure */
int bpb_secpertrk; /* Number of sectors per track */
int bpb_numheads; /* Number of heads */
int bpb_hiddsec; /* Hidden sectors before the volume */
unsigned int bpb_totsec32; /* Number of sectors on the volume
(new 32-bit) */
int last_word; /* 0xAA55 */
/**** FAT12/16 specific *****/
int bs_drvnum; /* Drive number */
int bs_bootsig; /* Is 0x29 if the following 3 fields are valid */
unsigned int bs_volid; /* Volume ID */
char bs_vollab[12]; /* Volume label, 11 chars plus \0 */
char bs_filsystype[9]; /* File system type, 8 chars plus \0 */
/**** FAT32 specific *****/
int bpb_fatsz32;
int bpb_extflags;
int bpb_fsver;
int bpb_rootclus;
int bpb_fsinfo;
int bpb_bkbootsec;
/* variables for internal use */
unsigned int fatsize;
unsigned int totalsectors;
unsigned int rootdirsector;
unsigned int firstdatasector;
unsigned int startsector;
unsigned int dataclusters;
struct fsinfo fsinfo;
};
static struct bpb fat_bpb;
static int update_fsinfo(void);
static int first_sector_of_cluster(int cluster);
static int bpb_is_sane(void);
static void *cache_fat_sector(int secnum);
static int create_dos_name(unsigned char *name, unsigned char *newname);
static unsigned int find_free_cluster(unsigned int start);
static int transfer( unsigned int start, int count, char* buf, bool write );
#define FAT_CACHE_SIZE 0x20
#define FAT_CACHE_MASK (FAT_CACHE_SIZE-1)
struct fat_cache_entry
{
int secnum;
bool inuse;
bool dirty;
};
static char fat_cache_sectors[FAT_CACHE_SIZE][SECTOR_SIZE];
static struct fat_cache_entry fat_cache[FAT_CACHE_SIZE];
static int sec2cluster(unsigned int sec)
{
if ( sec < fat_bpb.firstdatasector )
{
DEBUGF( "sec2cluster() - Bad sector number (%d)\n", sec);
return -1;
}
return ((sec - fat_bpb.firstdatasector) / fat_bpb.bpb_secperclus) + 2;
}
static int cluster2sec(int cluster)
{
int max_cluster = fat_bpb.totalsectors -
fat_bpb.firstdatasector / fat_bpb.bpb_secperclus + 1;
if(cluster > max_cluster)
{
DEBUGF( "cluster2sec() - Bad cluster number (%d)\n",
cluster);
return -1;
}
return first_sector_of_cluster(cluster);
}
static int first_sector_of_cluster(int cluster)
{
return (cluster - 2) * fat_bpb.bpb_secperclus + fat_bpb.firstdatasector;
}
int fat_startsector(void)
{
return fat_bpb.startsector;
}
void fat_size(unsigned int* size, unsigned int* free)
{
if (size)
*size = fat_bpb.dataclusters * fat_bpb.bpb_secperclus / 2;
if (free)
*free = fat_bpb.fsinfo.freecount * fat_bpb.bpb_secperclus / 2;
}
int fat_mount(int startsector)
{
unsigned char buf[SECTOR_SIZE];
int rc;
int datasec;
unsigned int i;
for(i = 0;i < FAT_CACHE_SIZE;i++)
{
fat_cache[i].secnum = 8; /* We use a "safe" sector just in case */
fat_cache[i].inuse = false;
fat_cache[i].dirty = false;
}
/* Read the sector */
rc = ata_read_sectors(startsector,1,buf);
if(rc)
{
DEBUGF( "fat_mount() - Couldn't read BPB (error code %d)\n", rc);
return rc * 10 - 1;
}
memset(&fat_bpb, 0, sizeof(struct bpb));
fat_bpb.startsector = startsector;
strncpy(fat_bpb.bs_oemname, &buf[BS_OEMNAME], 8);
fat_bpb.bs_oemname[8] = 0;
fat_bpb.bpb_bytspersec = BYTES2INT16(buf,BPB_BYTSPERSEC);
fat_bpb.bpb_secperclus = buf[BPB_SECPERCLUS];
fat_bpb.bpb_rsvdseccnt = BYTES2INT16(buf,BPB_RSVDSECCNT);
fat_bpb.bpb_numfats = buf[BPB_NUMFATS];
fat_bpb.bpb_totsec16 = BYTES2INT16(buf,BPB_TOTSEC16);
fat_bpb.bpb_media = buf[BPB_MEDIA];
fat_bpb.bpb_fatsz16 = BYTES2INT16(buf,BPB_FATSZ16);
fat_bpb.bpb_fatsz32 = BYTES2INT32(buf,BPB_FATSZ32);
fat_bpb.bpb_secpertrk = BYTES2INT16(buf,BPB_SECPERTRK);
fat_bpb.bpb_numheads = BYTES2INT16(buf,BPB_NUMHEADS);
fat_bpb.bpb_hiddsec = BYTES2INT32(buf,BPB_HIDDSEC);
fat_bpb.bpb_totsec32 = BYTES2INT32(buf,BPB_TOTSEC32);
fat_bpb.last_word = BYTES2INT16(buf,BPB_LAST_WORD);
/* calculate a few commonly used values */
if (fat_bpb.bpb_fatsz16 != 0)
fat_bpb.fatsize = fat_bpb.bpb_fatsz16;
else
fat_bpb.fatsize = fat_bpb.bpb_fatsz32;
if (fat_bpb.bpb_totsec16 != 0)
fat_bpb.totalsectors = fat_bpb.bpb_totsec16;
else
fat_bpb.totalsectors = fat_bpb.bpb_totsec32;
fat_bpb.firstdatasector = fat_bpb.bpb_rsvdseccnt +
fat_bpb.bpb_numfats * fat_bpb.fatsize;
/* Determine FAT type */
datasec = fat_bpb.totalsectors - fat_bpb.firstdatasector;
fat_bpb.dataclusters = datasec / fat_bpb.bpb_secperclus;
#ifdef TEST_FAT
/*
we are sometimes testing with "illegally small" fat32 images,
so we don't use the proper fat32 test case for test code
*/
if ( fat_bpb.bpb_fatsz16 )
#else
if ( fat_bpb.dataclusters < 65525 )
#endif
{
DEBUGF("This is not FAT32. Go away!\n");
return -2;
}
fat_bpb.bpb_extflags = BYTES2INT16(buf,BPB_EXTFLAGS);
fat_bpb.bpb_fsver = BYTES2INT16(buf,BPB_FSVER);
fat_bpb.bpb_rootclus = BYTES2INT32(buf,BPB_ROOTCLUS);
fat_bpb.bpb_fsinfo = BYTES2INT16(buf,BPB_FSINFO);
fat_bpb.bpb_bkbootsec = BYTES2INT16(buf,BPB_BKBOOTSEC);
fat_bpb.bs_drvnum = buf[BS_32_DRVNUM];
fat_bpb.bs_bootsig = buf[BS_32_BOOTSIG];
if(fat_bpb.bs_bootsig == 0x29)
{
fat_bpb.bs_volid = BYTES2INT32(buf,BS_32_VOLID);
strncpy(fat_bpb.bs_vollab, &buf[BS_32_VOLLAB], 11);
strncpy(fat_bpb.bs_filsystype, &buf[BS_32_FILSYSTYPE], 8);
}
rc = bpb_is_sane();
if (rc < 0)
{
DEBUGF( "fat_mount() - BPB is not sane\n");
return rc * 10 - 3;
}
fat_bpb.rootdirsector = cluster2sec(fat_bpb.bpb_rootclus);
/* Read the fsinfo sector */
rc = ata_read_sectors(startsector + fat_bpb.bpb_fsinfo, 1, buf);
if (rc < 0)
{
DEBUGF( "fat_mount() - Couldn't read FSInfo (error code %d)\n", rc);
return rc * 10 - 4;
}
fat_bpb.fsinfo.freecount = BYTES2INT32(buf, FSINFO_FREECOUNT);
fat_bpb.fsinfo.nextfree = BYTES2INT32(buf, FSINFO_NEXTFREE);
/* calculate freecount if unset */
if ( fat_bpb.fsinfo.freecount == 0xffffffff )
{
fat_recalc_free();
}
LDEBUGF("Freecount: %d\n",fat_bpb.fsinfo.freecount);
LDEBUGF("Nextfree: 0x%x\n",fat_bpb.fsinfo.nextfree);
LDEBUGF("Cluster count: 0x%x\n",fat_bpb.dataclusters);
LDEBUGF("Sectors per cluster: %d\n",fat_bpb.bpb_secperclus);
LDEBUGF("FAT sectors: 0x%x\n",fat_bpb.fatsize);
return 0;
}
void fat_recalc_free(void)
{
int free = 0;
unsigned i;
for (i = 0; i<fat_bpb.fatsize; i++) {
unsigned int j;
unsigned int* fat = cache_fat_sector(i);
for (j = 0; j < CLUSTERS_PER_FAT_SECTOR; j++) {
unsigned int c = i * CLUSTERS_PER_FAT_SECTOR + j;
if ( c > fat_bpb.dataclusters+1 ) /* nr 0 is unused */
break;
if (!(SWAB32(fat[j]) & 0x0fffffff)) {
free++;
if ( fat_bpb.fsinfo.nextfree == 0xffffffff )
fat_bpb.fsinfo.nextfree = c;
}
}
}
fat_bpb.fsinfo.freecount = free;
update_fsinfo();
}
static int bpb_is_sane(void)
{
if(fat_bpb.bpb_bytspersec != 512)
{
DEBUGF( "bpb_is_sane() - Error: sector size is not 512 (%d)\n",
fat_bpb.bpb_bytspersec);
return -1;
}
if(fat_bpb.bpb_secperclus * fat_bpb.bpb_bytspersec > 128*1024)
{
DEBUGF( "bpb_is_sane() - Error: cluster size is larger than 128K "
"(%d * %d = %d)\n",
fat_bpb.bpb_bytspersec, fat_bpb.bpb_secperclus,
fat_bpb.bpb_bytspersec * fat_bpb.bpb_secperclus);
return -2;
}
if(fat_bpb.bpb_numfats != 2)
{
DEBUGF( "bpb_is_sane() - Warning: NumFATS is not 2 (%d)\n",
fat_bpb.bpb_numfats);
}
if(fat_bpb.bpb_media != 0xf0 && fat_bpb.bpb_media < 0xf8)
{
DEBUGF( "bpb_is_sane() - Warning: Non-standard "
"media type (0x%02x)\n",
fat_bpb.bpb_media);
}
if(fat_bpb.last_word != 0xaa55)
{
DEBUGF( "bpb_is_sane() - Error: Last word is not "
"0xaa55 (0x%04x)\n", fat_bpb.last_word);
return -3;
}
if (fat_bpb.fsinfo.freecount >
(fat_bpb.totalsectors - fat_bpb.firstdatasector)/
fat_bpb.bpb_secperclus)
{
DEBUGF( "bpb_is_sane() - Error: FSInfo.Freecount > disk size "
"(0x%04x)\n", fat_bpb.fsinfo.freecount);
return -4;
}
return 0;
}
static void *cache_fat_sector(int fatsector)
{
int secnum = fatsector + fat_bpb.bpb_rsvdseccnt;
int cache_index = secnum & FAT_CACHE_MASK;
struct fat_cache_entry *fce = &fat_cache[cache_index];
unsigned char *sectorbuf = &fat_cache_sectors[cache_index][0];
int rc;
/* Delete the cache entry if it isn't the sector we want */
if(fce->inuse && fce->secnum != secnum)
{
/* Write back if it is dirty */
if(fce->dirty)
{
rc = ata_write_sectors(fce->secnum+fat_bpb.startsector, 1,
sectorbuf);
if(rc < 0)
{
panicf("cache_fat_sector() - Could not write sector %d"
" (error %d)\n",
secnum, rc);
}
if(fat_bpb.bpb_numfats > 1)
{
/* Write to the second FAT */
rc = ata_write_sectors(fce->secnum+fat_bpb.startsector+
fat_bpb.fatsize, 1, sectorbuf);
if(rc < 0)
{
panicf("cache_fat_sector() - Could not write sector %d"
" (error %d)\n",
secnum + fat_bpb.fatsize, rc);
}
}
}
fce->secnum = 8; /* Normally an unused sector */
fce->dirty = false;
fce->inuse = false;
}
/* Load the sector if it is not cached */
if(!fce->inuse)
{
rc = ata_read_sectors(secnum + fat_bpb.startsector,1,
sectorbuf);
if(rc < 0)
{
DEBUGF( "cache_fat_sector() - Could not read sector %d"
" (error %d)\n", secnum, rc);
return NULL;
}
fce->inuse = true;
fce->secnum = secnum;
}
return sectorbuf;
}
static unsigned int find_free_cluster(unsigned int startcluster)
{
unsigned int sector;
unsigned int offset;
unsigned int i;
sector = startcluster / CLUSTERS_PER_FAT_SECTOR;
offset = startcluster % CLUSTERS_PER_FAT_SECTOR;
for (i = 0; i<fat_bpb.fatsize; i++) {
unsigned int j;
unsigned int nr = (i + sector) % fat_bpb.fatsize;
unsigned int* fat = cache_fat_sector(nr);
if ( !fat )
break;
for (j = 0; j < CLUSTERS_PER_FAT_SECTOR; j++) {
int k = (j + offset) % CLUSTERS_PER_FAT_SECTOR;
if (!(SWAB32(fat[k]) & 0x0fffffff)) {
unsigned int c = nr * CLUSTERS_PER_FAT_SECTOR + k;
/* Ignore the reserved clusters 0 & 1, and also
cluster numbers out of bounds */
if ( c < 2 || c > fat_bpb.dataclusters+1 )
continue;
LDEBUGF("find_free_cluster(%x) == %x\n",startcluster,c);
fat_bpb.fsinfo.nextfree = c;
return c;
}
}
offset = 0;
}
LDEBUGF("find_free_cluster(%x) == 0\n",startcluster);
return 0; /* 0 is an illegal cluster number */
}
static int update_fat_entry(unsigned int entry, unsigned int val)
{
int sector = entry / CLUSTERS_PER_FAT_SECTOR;
int offset = entry % CLUSTERS_PER_FAT_SECTOR;
unsigned int* sec;
LDEBUGF("update_fat_entry(%x,%x)\n",entry,val);
if (entry==val)
panicf("Creating FAT loop: %x,%x\n",entry,val);
if ( entry < 2 )
panicf("Updating reserved FAT entry %d.\n",entry);
sec = cache_fat_sector(sector);
if (!sec)
{
DEBUGF( "update_entry() - Could not cache sector %d\n", sector);
return -1;
}
fat_cache[(sector + fat_bpb.bpb_rsvdseccnt) & FAT_CACHE_MASK].dirty = true;
if ( val ) {
if (!(SWAB32(sec[offset]) & 0x0fffffff) &&
fat_bpb.fsinfo.freecount > 0)
fat_bpb.fsinfo.freecount--;
}
else {
if (SWAB32(sec[offset]) & 0x0fffffff)
fat_bpb.fsinfo.freecount++;
}
LDEBUGF("update_fat_entry: %d free clusters\n", fat_bpb.fsinfo.freecount);
/* don't change top 4 bits */
sec[offset] &= SWAB32(0xf0000000);
sec[offset] |= SWAB32(val & 0x0fffffff);
return 0;
}
static int read_fat_entry(unsigned int entry)
{
int sector = entry / CLUSTERS_PER_FAT_SECTOR;
int offset = entry % CLUSTERS_PER_FAT_SECTOR;
unsigned int* sec;
sec = cache_fat_sector(sector);
if (!sec)
{
DEBUGF( "read_fat_entry() - Could not cache sector %d\n", sector);
return -1;
}
return SWAB32(sec[offset]) & 0x0fffffff;
}
static int get_next_cluster(unsigned int cluster)
{
int next_cluster;
next_cluster = read_fat_entry(cluster);
/* is this last cluster in chain? */
if ( next_cluster >= FAT_EOF_MARK )
return 0;
else
return next_cluster;
}
static int update_fsinfo(void)
{
unsigned char fsinfo[SECTOR_SIZE];
unsigned int* intptr;
int rc;
/* update fsinfo */
rc = ata_read_sectors(fat_bpb.startsector + fat_bpb.bpb_fsinfo, 1,fsinfo);
if (rc < 0)
{
DEBUGF( "flush_fat() - Couldn't read FSInfo (error code %d)\n", rc);
return rc * 10 - 1;
}
intptr = (int*)&(fsinfo[FSINFO_FREECOUNT]);
*intptr = SWAB32(fat_bpb.fsinfo.freecount);
intptr = (int*)&(fsinfo[FSINFO_NEXTFREE]);
*intptr = SWAB32(fat_bpb.fsinfo.nextfree);
rc = ata_write_sectors(fat_bpb.startsector + fat_bpb.bpb_fsinfo,1,fsinfo);
if (rc < 0)
{
DEBUGF( "flush_fat() - Couldn't write FSInfo (error code %d)\n", rc);
return rc * 10 - 2;
}
return 0;
}
static int flush_fat(void)
{
int i;
int rc;
unsigned char *sec;
int secnum;
LDEBUGF("flush_fat()\n");
for(i = 0;i < FAT_CACHE_SIZE;i++)
{
if(fat_cache[i].inuse && fat_cache[i].dirty)
{
secnum = fat_cache[i].secnum + fat_bpb.startsector;
LDEBUGF("Flushing FAT sector %x\n", secnum);
sec = fat_cache_sectors[i];
/* Write to the first FAT */
rc = ata_write_sectors(secnum, 1, sec);
if(rc)
{
DEBUGF( "flush_fat() - Couldn't write"
" sector %d (error %d)\n", secnum, rc);
return rc * 10 - 1;
}
if(fat_bpb.bpb_numfats > 1 )
{
/* Write to the second FAT */
rc = ata_write_sectors(secnum + fat_bpb.fatsize, 1, sec);
if (rc)
{
DEBUGF( "flush_fat() - Couldn't write"
" sector %d (error %d)\n",
secnum + fat_bpb.fatsize, rc);
return rc * 10 - 2;
}
}
fat_cache[i].dirty = false;
}
}
rc = update_fsinfo();
if (rc < 0)
return rc * 10 - 3;
return 0;
}
static void fat_time(unsigned short* date,
unsigned short* time,
unsigned short* tenth )
{
#ifdef HAVE_RTC
struct tm* tm = get_time();
if (date)
*date = ((tm->tm_year - 80) << 9) |
((tm->tm_mon + 1) << 5) |
tm->tm_mday;
if (time)
*time = (tm->tm_hour << 11) |
(tm->tm_min << 5) |
(tm->tm_sec >> 1);
if (tenth)
*tenth = (tm->tm_sec & 1) * 100;
#else
/* non-RTC version returns an increment from the supplied time, or a
* fixed standard time/date if no time given as input */
bool next_day = false;
if (time)
{
if (0 == *time)
{
/* set to 00:15:00 */
*time = (15 << 5);
}
else
{
unsigned short mins = (*time >> 5) & 0x003F;
unsigned short hours = (*time >> 11) & 0x001F;
if ((mins += 10) >= 60)
{
mins = 0;
hours++;
}
if ((++hours) >= 24)
{
hours = hours - 24;
next_day = true;
}
*time = (hours << 11) | (mins << 5);
}
}
if (date)
{
if (0 == *date)
{
/* set to 1 August 2003 */
*date = ((2003 - 1980) << 9) | (8 << 5) | 1;
}
else
{
unsigned short day = *date & 0x001F;
unsigned short month = (*date >> 5) & 0x000F;
unsigned short year = (*date >> 9) & 0x007F;
if (next_day)
{
/* do a very simple day increment - never go above 28 days */
if (++day > 28)
{
day = 1;
if (++month > 12)
{
month = 1;
year++;
}
}
*date = (year << 9) | (month << 5) | day;
}
}
}
if (tenth)
*tenth = 0;
#endif /* HAVE_RTC */
}
static int write_long_name(struct fat_file* file,
unsigned int firstentry,
unsigned int numentries,
unsigned char* name,
unsigned char* shortname,
bool is_directory)
{
unsigned char buf[SECTOR_SIZE];
unsigned char* entry;
unsigned int idx = firstentry % DIR_ENTRIES_PER_SECTOR;
unsigned int sector = firstentry / DIR_ENTRIES_PER_SECTOR;
unsigned int i, j=0;
unsigned char chksum = 0;
int nameidx=0, namelen = strlen(name);
int rc;
LDEBUGF("write_long_name(file:%x, first:%d, num:%d, name:%s)\n",
file->firstcluster, firstentry, numentries, name);
rc = fat_seek(file, sector);
if (rc<0)
return rc * 10 - 1;
rc = fat_readwrite(file, 1, buf, false);
if (rc<1)
return rc * 10 - 2;
/* calculate shortname checksum */
for (i=11; i>0; i--)
chksum = ((chksum & 1) ? 0x80 : 0) + (chksum >> 1) + shortname[j++];
/* calc position of last name segment */
if ( namelen > NAME_BYTES_PER_ENTRY )
for (nameidx=0;
nameidx < (namelen - NAME_BYTES_PER_ENTRY);
nameidx += NAME_BYTES_PER_ENTRY);
for (i=0; i < numentries; i++) {
/* new sector? */
if ( idx >= DIR_ENTRIES_PER_SECTOR ) {
/* update current sector */
rc = fat_seek(file, sector);
if (rc<0)
return rc * 10 - 3;
rc = fat_readwrite(file, 1, buf, true);
if (rc<1)
return rc * 10 - 4;
/* read next sector */
rc = fat_readwrite(file, 1, buf, false);
if (rc<0) {
LDEBUGF("Failed writing new sector: %d\n",rc);
return rc * 10 - 5;
}
if (rc==0)
/* end of dir */
memset(buf, 0, sizeof buf);
sector++;
idx = 0;
}
entry = buf + idx * DIR_ENTRY_SIZE;
/* verify this entry is free */
if (entry[0] && entry[0] != 0xe5 )
panicf("Dir entry %d in sector %x is not free! "
"%02x %02x %02x %02x",
idx, sector,
entry[0], entry[1], entry[2], entry[3]);
memset(entry, 0, DIR_ENTRY_SIZE);
if ( i+1 < numentries ) {
/* longname entry */
int k, l = nameidx;
entry[FATLONG_ORDER] = numentries-i-1;
if (i==0) {
/* mark this as last long entry */
entry[FATLONG_ORDER] |= 0x40;
/* pad name with 0xffff */
for (k=1; k<12; k++) entry[k] = 0xff;
for (k=14; k<26; k++) entry[k] = 0xff;
for (k=28; k<32; k++) entry[k] = 0xff;
};
/* set name */
for (k=0; k<5 && l <= namelen; k++) {
entry[k*2 + 1] = name[l++];
entry[k*2 + 2] = 0;
}
for (k=0; k<6 && l <= namelen; k++) {
entry[k*2 + 14] = name[l++];
entry[k*2 + 15] = 0;
}
for (k=0; k<2 && l <= namelen; k++) {
entry[k*2 + 28] = name[l++];
entry[k*2 + 29] = 0;
}
entry[FATDIR_ATTR] = FAT_ATTR_LONG_NAME;
entry[FATDIR_FSTCLUSLO] = 0;
entry[FATLONG_TYPE] = 0;
entry[FATLONG_CHKSUM] = chksum;
LDEBUGF("Longname entry %d: %.13s\n", idx, name+nameidx);
}
else {
/* shortname entry */
unsigned short date=0, time=0, tenth=0;
LDEBUGF("Shortname entry: %.13s\n", shortname);
strncpy(entry + FATDIR_NAME, shortname, 11);
entry[FATDIR_ATTR] = is_directory?FAT_ATTR_DIRECTORY:0;
entry[FATDIR_NTRES] = 0;
fat_time(&date, &time, &tenth);
entry[FATDIR_CRTTIMETENTH] = tenth;
*(unsigned short*)(entry + FATDIR_CRTTIME) = SWAB16(time);
*(unsigned short*)(entry + FATDIR_WRTTIME) = SWAB16(time);
*(unsigned short*)(entry + FATDIR_CRTDATE) = SWAB16(date);
*(unsigned short*)(entry + FATDIR_WRTDATE) = SWAB16(date);
*(unsigned short*)(entry + FATDIR_LSTACCDATE) = SWAB16(date);
}
idx++;
nameidx -= NAME_BYTES_PER_ENTRY;
}
/* update last sector */
rc = fat_seek(file, sector);
if (rc<0)
return rc * 10 - 6;
rc = fat_readwrite(file, 1, buf, true);
if (rc<1)
return rc * 10 - 7;
return 0;
}
static int add_dir_entry(struct fat_dir* dir,
struct fat_file* file,
char* name,
bool is_directory,
bool dotdir)
{
unsigned char buf[SECTOR_SIZE];
unsigned char shortname[16];
int rc;
unsigned int sector;
bool done = false;
bool eof = false;
bool last = false;
int entries_needed, entries_found = 0;
int namelen = strlen(name);
int firstentry;
LDEBUGF( "add_dir_entry(%s,%x)\n",
name, file->firstcluster);
/* The "." and ".." directory entries must not be long names */
if(dotdir) {
int i;
strncpy(shortname, name, 16);
for(i = strlen(shortname);i < 12;i++)
shortname[i] = ' ';
entries_needed = 1;
} else {
/* create dos name */
rc = create_dos_name(name, shortname);
if (rc < 0)
return rc * 10 - 0;
/* one dir entry needed for every 13 bytes of filename,
plus one entry for the short name */
entries_needed = namelen / NAME_BYTES_PER_ENTRY + 1;
if (namelen % NAME_BYTES_PER_ENTRY)
entries_needed++;
}
restart:
firstentry = 0;
rc = fat_seek(&dir->file, 0);
if (rc < 0)
return rc * 10 - 1;
for (sector=0; !done; sector++)
{
unsigned int i;
rc = 0;
if (!eof) {
rc = fat_readwrite(&dir->file, 1, buf, false);
}
if (rc == 0) {
/* eof: add new sector */
eof = true;
memset(buf, 0, sizeof buf);
LDEBUGF("Adding new sector to dir\n");
rc = fat_seek(&dir->file, sector);
if (rc < 0)
return rc * 10 - 2;
/* add sectors (we must clear the whole cluster) */
do {
rc = fat_readwrite(&dir->file, 1, buf, true);
if (rc < 1)
return rc * 10 - 3;
} while (dir->file.sectornum < (int)fat_bpb.bpb_secperclus);
}
if (rc < 0) {
DEBUGF( "add_dir_entry() - Couldn't read dir"
" (error code %d)\n", rc);
return rc * 10 - 4;
}
/* look for free slots */
for (i=0; i < DIR_ENTRIES_PER_SECTOR && !done; i++)
{
unsigned char firstbyte = buf[i * DIR_ENTRY_SIZE];
switch (firstbyte) {
case 0: /* end of dir */
entries_found = entries_needed;
LDEBUGF("Found last entry %d\n",
sector * DIR_ENTRIES_PER_SECTOR + i);
done = true;
break;
case 0xe5: /* free entry */
entries_found++;
LDEBUGF("Found free entry %d (%d/%d)\n",
sector * DIR_ENTRIES_PER_SECTOR + i,
entries_found, entries_needed);
break;
default:
entries_found = 0;
/* check that our intended shortname doesn't already exist */
if (!strncmp(shortname, buf + i * DIR_ENTRY_SIZE, 12)) {
/* filename exists already. make a new one */
snprintf(shortname+8, 4, "%03X", (unsigned)rand() & 0xfff);
LDEBUGF("Duplicate shortname, changing to %s\n",
shortname);
/* name has changed, we need to restart search */
goto restart;
}
break;
}
if (!firstentry && (entries_found == entries_needed)) {
firstentry = sector * DIR_ENTRIES_PER_SECTOR + i;
/* if we're not extending the dir,
we must go back to first free entry */
if (done)
last = true;
else
firstentry -= (entries_needed - 1);
}
}
}
sector = firstentry / DIR_ENTRIES_PER_SECTOR;
LDEBUGF("Adding longname to entry %d in sector %d\n",
firstentry, sector);
rc = write_long_name(&dir->file, firstentry,
entries_needed, name, shortname, is_directory);
if (rc < 0)
return rc * 10 - 5;
/* remember where the shortname dir entry is located */
file->direntry = firstentry + entries_needed - 1;
file->direntries = entries_needed;
file->dircluster = dir->file.firstcluster;
LDEBUGF("Added new dir entry %d, using %d slots.\n",
file->direntry, file->direntries);
/* advance the end-of-dir marker? */
if (last)
{
unsigned int lastentry = firstentry + entries_needed;
LDEBUGF("Updating end-of-dir entry %d\n",lastentry);
if (lastentry % DIR_ENTRIES_PER_SECTOR)
{
int idx = (lastentry % DIR_ENTRIES_PER_SECTOR) * DIR_ENTRY_SIZE;
rc = fat_seek(&dir->file, lastentry / DIR_ENTRIES_PER_SECTOR);
if (rc < 0)
return rc * 10 - 6;
rc = fat_readwrite(&dir->file, 1, buf, false);
if (rc < 1)
return rc * 10 - 7;
/* clear last entry */
buf[idx] = 0;
rc = fat_seek(&dir->file, lastentry / DIR_ENTRIES_PER_SECTOR);
if (rc < 0)
return rc * 10 - 8;
/* we must clear entire last cluster */
do {
rc = fat_readwrite(&dir->file, 1, buf, true);
if (rc < 1)
return rc * 10 - 9;
memset(buf, 0, sizeof buf);
} while (dir->file.sectornum < (int)fat_bpb.bpb_secperclus);
}
else
{
/* add a new sector/cluster for last entry */
memset(buf, 0, sizeof buf);
do {
rc = fat_readwrite(&dir->file, 1, buf, true);
if (rc < 1)
return rc * 10 - 9; /* Same error code as above, can't be
more than -9 */
} while (dir->file.sectornum < (int)fat_bpb.bpb_secperclus);
}
}
return 0;
}
unsigned char char2dos(unsigned char c)
{
switch(c)
{
case 0xe5: /* Special kanji character */
c = 0x05;
break;
case 0x20:
case 0x22:
case 0x2a:
case 0x2b:
case 0x2c:
case 0x2e:
case 0x3a:
case 0x3b:
case 0x3c:
case 0x3d:
case 0x3e:
case 0x3f:
case 0x5b:
case 0x5c:
case 0x5d:
case 0x7c:
/* Illegal name */
c = 0;
break;
default:
if(c < 0x20)
{
/* Illegal name */
c = 0;
}
break;
}
return c;
}
static int create_dos_name(unsigned char *name, unsigned char *newname)
{
int i,j;
/* Name part */
for (i=0, j=0; name[i] && (j < 8); i++)
{
unsigned char c = char2dos(name[i]);
if (c)
newname[j++] = toupper(c);
}
while (j < 8)
newname[j++] = ' ';
/* Extension part */
snprintf(newname+8, 4, "%03X", (unsigned)rand() & 0xfff);
return 0;
}
static int update_short_entry( struct fat_file* file, int size, int attr )
{
unsigned char buf[SECTOR_SIZE];
int sector = file->direntry / DIR_ENTRIES_PER_SECTOR;
unsigned char* entry =
buf + DIR_ENTRY_SIZE * (file->direntry % DIR_ENTRIES_PER_SECTOR);
unsigned int* sizeptr;
unsigned short* clusptr;
struct fat_file dir;
int rc;
LDEBUGF("update_file_size(cluster:%x entry:%d size:%d)\n",
file->firstcluster, file->direntry, size);
/* create a temporary file handle for the dir holding this file */
rc = fat_open(file->dircluster, &dir, NULL);
if (rc < 0)
return rc * 10 - 1;
rc = fat_seek( &dir, sector );
if (rc<0)
return rc * 10 - 2;
rc = fat_readwrite(&dir, 1, buf, false);
if (rc < 1)
return rc * 10 - 3;
if (!entry[0] || entry[0] == 0xe5)
panicf("Updating size on empty dir entry %d\n", file->direntry);
entry[FATDIR_ATTR] = attr & 0xFF;
clusptr = (short*)(entry + FATDIR_FSTCLUSHI);
*clusptr = SWAB16(file->firstcluster >> 16);
clusptr = (short*)(entry + FATDIR_FSTCLUSLO);
*clusptr = SWAB16(file->firstcluster & 0xffff);
sizeptr = (int*)(entry + FATDIR_FILESIZE);
*sizeptr = SWAB32(size);
{
#ifdef HAVE_RTC
unsigned short time = 0;
unsigned short date = 0;
#else
/* get old time to increment from */
unsigned short time = SWAB16(*(unsigned short*)(entry + FATDIR_WRTTIME));
unsigned short date = SWAB16(*(unsigned short*)(entry + FATDIR_WRTDATE));
#endif
fat_time(&date, &time, NULL);
*(unsigned short*)(entry + FATDIR_WRTTIME) = SWAB16(time);
*(unsigned short*)(entry + FATDIR_WRTDATE) = SWAB16(date);
*(unsigned short*)(entry + FATDIR_LSTACCDATE) = SWAB16(date);
}
rc = fat_seek( &dir, sector );
if (rc < 0)
return rc * 10 - 4;
rc = fat_readwrite(&dir, 1, buf, true);
if (rc < 1)
return rc * 10 - 5;
return 0;
}
static int parse_direntry(struct fat_direntry *de, unsigned char *buf)
{
int i=0,j=0;
memset(de, 0, sizeof(struct fat_direntry));
de->attr = buf[FATDIR_ATTR];
de->crttimetenth = buf[FATDIR_CRTTIMETENTH];
de->crtdate = BYTES2INT16(buf,FATDIR_CRTDATE);
de->crttime = BYTES2INT16(buf,FATDIR_CRTTIME);
de->wrtdate = BYTES2INT16(buf,FATDIR_WRTDATE);
de->wrttime = BYTES2INT16(buf,FATDIR_WRTTIME);
de->filesize = BYTES2INT32(buf,FATDIR_FILESIZE);
de->firstcluster = BYTES2INT16(buf,FATDIR_FSTCLUSLO) |
(BYTES2INT16(buf,FATDIR_FSTCLUSHI) << 16);
/* fix the name */
for (i=0; (i<8) && (buf[FATDIR_NAME+i] != ' '); i++)
de->name[j++] = buf[FATDIR_NAME+i];
if ( buf[FATDIR_NAME+8] != ' ' ) {
de->name[j++] = '.';
for (i=8; (i<11) && (buf[FATDIR_NAME+i] != ' '); i++)
de->name[j++] = buf[FATDIR_NAME+i];
}
return 1;
}
int fat_open(unsigned int startcluster,
struct fat_file *file,
struct fat_dir* dir)
{
file->firstcluster = startcluster;
file->lastcluster = startcluster;
file->lastsector = 0;
file->clusternum = 0;
file->sectornum = 0;
file->eof = false;
/* remember where the file's dir entry is located */
if ( dir ) {
file->direntry = dir->entry - 1;
file->direntries = dir->entrycount;
file->dircluster = dir->file.firstcluster;
}
LDEBUGF("fat_open(%x), entry %d\n",startcluster,file->direntry);
return 0;
}
int fat_create_file(char* name,
struct fat_file* file,
struct fat_dir* dir)
{
int rc;
LDEBUGF("fat_create_file(\"%s\",%x,%x)\n",name,file,dir);
rc = add_dir_entry(dir, file, name, false, false);
if (!rc) {
file->firstcluster = 0;
file->lastcluster = 0;
file->lastsector = 0;
file->clusternum = 0;
file->sectornum = 0;
file->eof = false;
}
return rc;
}
int fat_create_dir(char* name,
struct fat_dir* newdir,
struct fat_dir* dir)
{
unsigned char buf[SECTOR_SIZE];
int i;
int sector;
int rc;
struct fat_file dummyfile;
LDEBUGF("fat_create_dir(\"%s\",%x,%x)\n",name,newdir,dir);
memset(newdir, 0, sizeof(struct fat_dir));
memset(&dummyfile, 0, sizeof(struct fat_file));
/* First, add the entry in the parent directory */
rc = add_dir_entry(dir, &newdir->file, name, true, false);
if (rc < 0)
return rc * 10 - 1;
/* Allocate a new cluster for the directory */
newdir->file.firstcluster = find_free_cluster(fat_bpb.fsinfo.nextfree);
if(newdir->file.firstcluster == 0)
return -1;
update_fat_entry(newdir->file.firstcluster, FAT_EOF_MARK);
/* Clear the entire cluster */
memset(buf, 0, sizeof buf);
sector = cluster2sec(newdir->file.firstcluster);
for(i = 0;i < (int)fat_bpb.bpb_secperclus;i++) {
rc = transfer( sector + fat_bpb.startsector + i, 1, buf, true );
if (rc < 0)
return rc * 10 - 2;
}
/* Then add the "." entry */
rc = add_dir_entry(newdir, &dummyfile, ".", true, true);
if (rc < 0)
return rc * 10 - 3;
dummyfile.firstcluster = newdir->file.firstcluster;
update_short_entry(&dummyfile, 0, FAT_ATTR_DIRECTORY);
/* and the ".." entry */
rc = add_dir_entry(newdir, &dummyfile, "..", true, true);
if (rc < 0)
return rc * 10 - 4;
/* The root cluster is cluster 0 in the ".." entry */
if(dir->file.firstcluster == fat_bpb.bpb_rootclus)
dummyfile.firstcluster = 0;
else
dummyfile.firstcluster = dir->file.firstcluster;
update_short_entry(&dummyfile, 0, FAT_ATTR_DIRECTORY);
/* Set the firstcluster field in the direntry */
update_short_entry(&newdir->file, 0, FAT_ATTR_DIRECTORY);
rc = flush_fat();
if (rc < 0)
return rc * 10 - 5;
return rc;
}
int fat_truncate(struct fat_file *file)
{
/* truncate trailing clusters */
int next;
int last = file->lastcluster;
LDEBUGF("fat_truncate(%x, %x)\n", file->firstcluster, last);
for ( last = get_next_cluster(last); last; last = next ) {
next = get_next_cluster(last);
update_fat_entry(last,0);
}
if (file->lastcluster)
update_fat_entry(file->lastcluster,FAT_EOF_MARK);
return 0;
}
int fat_closewrite(struct fat_file *file, int size, int attr)
{
int rc;
LDEBUGF("fat_closewrite(size=%d)\n",size);
if (!size) {
/* empty file */
if ( file->firstcluster ) {
update_fat_entry(file->firstcluster, 0);
file->firstcluster = 0;
}
}
if (file->dircluster) {
rc = update_short_entry(file, size, attr);
if (rc < 0)
return rc * 10 - 1;
}
flush_fat();
#ifdef TEST_FAT
if ( file->firstcluster ) {
/* debug */
int count = 0;
int len;
int next;
for ( next = file->firstcluster; next;
next = get_next_cluster(next) )
LDEBUGF("cluster %d: %x\n", count++, next);
len = count * fat_bpb.bpb_secperclus * SECTOR_SIZE;
LDEBUGF("File is %d clusters (chainlen=%d, size=%d)\n",
count, len, size );
if ( len > size + fat_bpb.bpb_secperclus * SECTOR_SIZE)
panicf("Cluster chain is too long\n");
if ( len < size )
panicf("Cluster chain is too short\n");
}
#endif
return 0;
}
static int free_direntries(int dircluster, int startentry, int numentries)
{
unsigned char buf[SECTOR_SIZE];
struct fat_file dir;
unsigned int entry = startentry - numentries + 1;
unsigned int sector = entry / DIR_ENTRIES_PER_SECTOR;
int i;
int rc;
/* create a temporary file handle for the dir holding this file */
rc = fat_open(dircluster, &dir, NULL);
if (rc < 0)
return rc * 10 - 1;
rc = fat_seek( &dir, sector );
if (rc < 0)
return rc * 10 - 2;
rc = fat_readwrite(&dir, 1, buf, false);
if (rc < 1)
return rc * 10 - 3;
for (i=0; i < numentries; i++) {
LDEBUGF("Clearing dir entry %d (%d/%d)\n",
entry, i+1, numentries);
buf[(entry % DIR_ENTRIES_PER_SECTOR) * DIR_ENTRY_SIZE] = 0xe5;
entry++;
if ( (entry % DIR_ENTRIES_PER_SECTOR) == 0 ) {
/* flush this sector */
rc = fat_seek(&dir, sector);
if (rc < 0)
return rc * 10 - 4;
rc = fat_readwrite(&dir, 1, buf, true);
if (rc < 1)
return rc * 10 - 5;
if ( i+1 < numentries ) {
/* read next sector */
rc = fat_readwrite(&dir, 1, buf, false);
if (rc < 1)
return rc * 10 - 6;
}
sector++;
}
}
if ( entry % DIR_ENTRIES_PER_SECTOR ) {
/* flush this sector */
rc = fat_seek(&dir, sector);
if (rc < 0)
return rc * 10 - 7;
rc = fat_readwrite(&dir, 1, buf, true);
if (rc < 1)
return rc * 10 - 8;
}
return 0;
}
int fat_remove(struct fat_file* file)
{
int next, last = file->firstcluster;
int rc;
LDEBUGF("fat_remove(%x)\n",last);
while ( last ) {
next = get_next_cluster(last);
update_fat_entry(last,0);
last = next;
}
if ( file->dircluster ) {
rc = free_direntries(file->dircluster,
file->direntry,
file->direntries);
if (rc < 0)
return rc * 10 - 1;
}
file->firstcluster = 0;
file->dircluster = 0;
rc = flush_fat();
if (rc < 0)
return rc * 10 - 2;
return 0;
}
int fat_rename(struct fat_file* file,
unsigned char* newname,
int size,
int attr)
{
int rc;
struct fat_dir dir;
struct fat_file newfile = *file;
if ( !file->dircluster ) {
DEBUGF("File has no dir cluster!\n");
return -1;
}
/* create a temporary file handle */
rc = fat_opendir(&dir, file->dircluster, NULL);
if (rc < 0)
return rc * 10 - 2;
/* create new name */
rc = add_dir_entry(&dir, &newfile, newname, false, false);
if (rc < 0)
return rc * 10 - 3;
/* write size and cluster link */
rc = update_short_entry(&newfile, size, attr);
if (rc < 0)
return rc * 10 - 4;
/* remove old name */
rc = free_direntries(file->dircluster, file->direntry, file->direntries);
if (rc < 0)
return rc * 10 - 5;
rc = flush_fat();
if (rc < 0)
return rc * 10 - 6;
return 0;
}
static int next_write_cluster(struct fat_file* file,
int oldcluster,
int* newsector)
{
int cluster = 0;
int sector;
LDEBUGF("next_write_cluster(%x,%x)\n",file->firstcluster, oldcluster);
if (oldcluster)
cluster = get_next_cluster(oldcluster);
if (!cluster) {
if (oldcluster)
cluster = find_free_cluster(oldcluster+1);
else
cluster = find_free_cluster(fat_bpb.fsinfo.nextfree);
if (cluster) {
if (oldcluster)
update_fat_entry(oldcluster, cluster);
else
file->firstcluster = cluster;
update_fat_entry(cluster, FAT_EOF_MARK);
}
else {
#ifdef TEST_FAT
if (fat_bpb.fsinfo.freecount>0)
panicf("There is free space, but find_free_cluster() "
"didn't find it!\n");
#endif
DEBUGF("next_write_cluster(): Disk full!\n");
return 0;
}
}
sector = cluster2sec(cluster);
if (sector<0)
return 0;
*newsector = sector;
return cluster;
}
static int transfer( unsigned int start, int count, char* buf, bool write )
{
int rc;
LDEBUGF("transfer(s=%x, c=%x, %s)\n",start, count, write?"write":"read");
if (write) {
if (start < fat_bpb.firstdatasector)
panicf("Writing before data\n");
rc = ata_write_sectors(start, count, buf);
}
else
rc = ata_read_sectors(start, count, buf);
if (rc < 0) {
DEBUGF( "transfer() - Couldn't %s sector %x"
" (error code %d)\n",
write ? "write":"read", start, rc);
return rc;
}
return 0;
}
int fat_readwrite( struct fat_file *file, int sectorcount,
void* buf, bool write )
{
int cluster = file->lastcluster;
int sector = file->lastsector;
int clusternum = file->clusternum;
int numsec = file->sectornum;
bool eof = file->eof;
int first=0, last=0;
int i;
int rc;
LDEBUGF( "fat_readwrite(file:%x,count:0x%x,buf:%x,%s)\n",
file->firstcluster,sectorcount,buf,write?"write":"read");
LDEBUGF( "fat_readwrite: sec=%x numsec=%d eof=%d\n",
sector,numsec, eof?1:0);
if ( eof && !write)
return 0;
/* find sequential sectors and write them all at once */
for (i=0; (i < sectorcount) && (sector > -1); i++ ) {
numsec++;
if ( numsec > (int)fat_bpb.bpb_secperclus || !cluster ) {
int oldcluster = cluster;
if (write)
cluster = next_write_cluster(file, cluster, &sector);
else {
cluster = get_next_cluster(cluster);
sector = cluster2sec(cluster);
}
clusternum++;
numsec=1;
if (!cluster) {
eof = true;
if ( write ) {
/* remember last cluster, in case
we want to append to the file */
cluster = oldcluster;
clusternum--;
i = -1; /* Error code */
break;
}
}
else
eof = false;
}
else {
if (sector)
sector++;
else {
/* look up first sector of file */
sector = cluster2sec(file->firstcluster);
numsec=1;
}
}
if (!first)
first = sector;
if ( ((sector != first) && (sector != last+1)) || /* not sequential */
(last-first+1 == 256) ) { /* max 256 sectors per ata request */
int count = last - first + 1;
rc = transfer( first + fat_bpb.startsector, count, buf, write );
if (rc < 0)
return rc * 10 - 1;
buf = (char *)buf + count * SECTOR_SIZE;
first = sector;
}
if ((i == sectorcount-1) && /* last sector requested */
(!eof))
{
int count = sector - first + 1;
rc = transfer( first + fat_bpb.startsector, count, buf, write );
if (rc < 0)
return rc * 10 - 2;
}
last = sector;
}
file->lastcluster = cluster;
file->lastsector = sector;
file->clusternum = clusternum;
file->sectornum = numsec;
file->eof = eof;
/* if eof, don't report last block as read/written */
if (eof)
i--;
DEBUGF("Sectors written: %d\n", i);
return i;
}
int fat_seek(struct fat_file *file, unsigned int seeksector )
{
int clusternum=0, numclusters=0, sectornum=0, sector=0;
int cluster = file->firstcluster;
int i;
file->eof = false;
if (seeksector) {
/* we need to find the sector BEFORE the requested, since
the file struct stores the last accessed sector */
seeksector--;
numclusters = clusternum = seeksector / fat_bpb.bpb_secperclus;
sectornum = seeksector % fat_bpb.bpb_secperclus;
if (file->clusternum && clusternum >= file->clusternum)
{
cluster = file->lastcluster;
numclusters -= file->clusternum;
}
for (i=0; i<numclusters; i++) {
cluster = get_next_cluster(cluster);
if (!cluster) {
DEBUGF("Seeking beyond the end of the file! "
"(sector %d, cluster %d)\n", seeksector, i);
return -1;
}
}
sector = cluster2sec(cluster) + sectornum;
}
else {
sectornum = -1;
}
LDEBUGF("fat_seek(%x, %x) == %x, %x, %x\n",
file->firstcluster, seeksector, cluster, sector, sectornum);
file->lastcluster = cluster;
file->lastsector = sector;
file->clusternum = clusternum;
file->sectornum = sectornum + 1;
return 0;
}
int fat_opendir(struct fat_dir *dir, unsigned int startcluster,
struct fat_dir *parent_dir)
{
int rc;
if (startcluster == 0)
startcluster = sec2cluster(fat_bpb.rootdirsector);
rc = fat_open(startcluster, &dir->file, parent_dir);
if(rc)
{
DEBUGF( "fat_opendir() - Couldn't open dir"
" (error code %d)\n", rc);
return rc * 10 - 1;
}
dir->entry = 0;
dir->sector = 0;
return 0;
}
/* convert from unicode to a single-byte charset */
static void unicode2iso(unsigned char* unicode, unsigned char* iso, int count )
{
int i;
for (i=0; i<count; i++) {
int x = i*2;
switch (unicode[x+1]) {
case 0x01: /* latin extended. convert to ISO 8859-2 */
case 0x02:
iso[i] = unicode2iso8859_2[unicode[x]];
break;
case 0x03: /* greek, convert to ISO 8859-7 */
iso[i] = unicode[x] + 0x30;
break;
/* Sergei says most russians use Win1251, so we will too.
Win1251 differs from ISO 8859-5 by an offset of 0x10. */
case 0x04: /* cyrillic, convert to Win1251 */
switch (unicode[x]) {
case 1:
iso[i] = 168;
break;
case 81:
iso[i] = 184;
break;
default:
iso[i] = unicode[x] + 0xb0; /* 0xa0 for ISO 8859-5 */
break;
}
break;
case 0x05: /* hebrew, convert to ISO 8859-8 */
iso[i] = unicode[x] + 0x10;
break;
case 0x06: /* arabic, convert to ISO 8859-6 */
case 0x0e: /* thai, convert to ISO 8859-11 */
iso[i] = unicode[x] + 0xa0;
break;
default:
iso[i] = unicode[x];
break;
}
}
}
int fat_getnext(struct fat_dir *dir, struct fat_direntry *entry)
{
bool done = false;
int i;
int rc;
unsigned char firstbyte;
int longarray[20];
int longs=0;
int sectoridx=0;
unsigned char* cached_buf = dir->sectorcache[0];
dir->entrycount = 0;
while(!done)
{
if ( !(dir->entry % DIR_ENTRIES_PER_SECTOR) || !dir->sector )
{
rc = fat_readwrite(&dir->file, 1, cached_buf, false);
if (rc == 0) {
/* eof */
entry->name[0] = 0;
break;
}
if (rc < 0) {
DEBUGF( "fat_getnext() - Couldn't read dir"
" (error code %d)\n", rc);
return rc * 10 - 1;
}
dir->sector = dir->file.lastsector;
}
for (i = dir->entry % DIR_ENTRIES_PER_SECTOR;
i < DIR_ENTRIES_PER_SECTOR; i++)
{
unsigned int entrypos = i * DIR_ENTRY_SIZE;
firstbyte = cached_buf[entrypos];
dir->entry++;
if (firstbyte == 0xe5) {
/* free entry */
sectoridx = 0;
dir->entrycount = 0;
continue;
}
if (firstbyte == 0) {
/* last entry */
entry->name[0] = 0;
dir->entrycount = 0;
return 0;
}
dir->entrycount++;
/* longname entry? */
if ( ( cached_buf[entrypos + FATDIR_ATTR] &
FAT_ATTR_LONG_NAME_MASK ) == FAT_ATTR_LONG_NAME ) {
longarray[longs++] = entrypos + sectoridx;
}
else {
if ( parse_direntry(entry,
&cached_buf[entrypos]) ) {
/* don't return volume id entry */
if ( entry->attr == FAT_ATTR_VOLUME_ID )
continue;
/* replace shortname with longname? */
if ( longs ) {
int j,l=0;
/* iterate backwards through the dir entries */
for (j=longs-1; j>=0; j--) {
unsigned char* ptr = cached_buf;
int index = longarray[j];
/* current or cached sector? */
if ( sectoridx >= SECTOR_SIZE ) {
if ( sectoridx >= SECTOR_SIZE*2 ) {
if ( ( index >= SECTOR_SIZE ) &&
( index < SECTOR_SIZE*2 ))
ptr = dir->sectorcache[1];
else
ptr = dir->sectorcache[2];
}
else {
if ( index < SECTOR_SIZE )
ptr = dir->sectorcache[1];
}
index &= SECTOR_SIZE-1;
}
/* names are stored in unicode, but we
only grab the low byte (iso8859-1). */
unicode2iso(ptr + index + 1, entry->name + l, 5);
l+= 5;
unicode2iso(ptr + index + 14, entry->name + l, 6);
l+= 6;
unicode2iso(ptr + index + 28, entry->name + l, 2);
l+= 2;
}
entry->name[l]=0;
}
done = true;
sectoridx = 0;
i++;
break;
}
}
}
/* save this sector, for longname use */
if ( sectoridx )
memcpy( dir->sectorcache[2], dir->sectorcache[0], SECTOR_SIZE );
else
memcpy( dir->sectorcache[1], dir->sectorcache[0], SECTOR_SIZE );
sectoridx += SECTOR_SIZE;
}
return 0;
}
int fat_get_cluster_size(void)
{
return fat_bpb.bpb_secperclus * SECTOR_SIZE;
}