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cleaned out parts of bpb which we don't use

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@5274 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Jörg Hohensohn 2004-10-14 07:52:08 +00:00
parent 87ab7a07a6
commit fb0739bdf0
1 changed files with 3 additions and 45 deletions
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48
firmware/drivers/fat.c
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@ -190,36 +190,21 @@ struct fsinfo {
struct bpb
{
char bs_oemname[9]; /* OEM string, ending with \0 */
int bpb_bytspersec; /* Bytes per sectory, typically 512 */
int bpb_bytspersec; /* Bytes per sector, 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;
@ -230,6 +215,7 @@ struct bpb
unsigned int dataclusters;
struct fsinfo fsinfo;
#ifdef HAVE_FAT16SUPPORT
int bpb_rootentcnt; /* Number of dir entries in the root */
/* internals for FAT16 support */
bool is_fat16; /* true if we mounted a FAT16 partition, false if FAT32 */
unsigned int rootdirsectors; /* fixed # of sectors occupied by root dir */
@ -334,21 +320,14 @@ int fat_mount(int startsector)
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_rootentcnt = BYTES2INT16(buf,BPB_ROOTENTCNT); /* needed only for FAT16 */
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);
@ -364,6 +343,7 @@ int fat_mount(int startsector)
fat_bpb.totalsectors = fat_bpb.bpb_totsec32;
#ifdef HAVE_FAT16SUPPORT
fat_bpb.bpb_rootentcnt = BYTES2INT16(buf,BPB_ROOTENTCNT);
fat_bpb.rootdirsectors = ((fat_bpb.bpb_rootentcnt * 32)
+ (fat_bpb.bpb_bytspersec - 1)) / fat_bpb.bpb_bytspersec;
#endif /* #ifdef HAVE_FAT16SUPPORT */
@ -405,15 +385,6 @@ int fat_mount(int startsector)
if (fat_bpb.is_fat16)
{ /* FAT16 specific part of BPB */
int dirclusters;
fat_bpb.bs_drvnum = buf[BS_DRVNUM];
fat_bpb.bs_bootsig = buf[BS_BOOTSIG];
if(fat_bpb.bs_bootsig == 0x29)
{
fat_bpb.bs_volid = BYTES2INT32(buf, BS_VOLID);
strncpy(fat_bpb.bs_vollab, &buf[BS_VOLLAB], 11);
strncpy(fat_bpb.bs_filsystype, &buf[BS_FILSYSTYPE], 8);
}
fat_bpb.rootdirsector = fat_bpb.bpb_rsvdseccnt
+ fat_bpb.bpb_numfats * fat_bpb.bpb_fatsz16;
dirclusters = ((fat_bpb.rootdirsectors + fat_bpb.bpb_secperclus - 1)
@ -425,21 +396,8 @@ int fat_mount(int startsector)
else
#endif /* #ifdef HAVE_FAT16SUPPORT */
{ /* FAT32 specific part of BPB */
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);
}
fat_bpb.rootdirsector = cluster2sec(fat_bpb.bpb_rootclus);
}