/*
* Mount DOS filesystem
*/
static int
dos_mount(DOS_FS *fs, struct open_file *fd)
{
int err;
struct devdesc *dd = fd->f_devdata;
u_char *buf;
bzero(fs, sizeof(DOS_FS));
fs->fd = fd;
if ((err = !(buf = malloc(secbyt(1))) ? errno : 0) ||
(err = ioget(fs->fd, 0, 0, buf, secbyt(1))) ||
(err = parsebs(fs, (DOS_BS *)buf))) {
if (buf != NULL)
free(buf);
(void)dosunmount(fs);
return(err);
}
free(buf);
if (fat.buf == NULL || fat.unit != dd->d_unit)
dos_read_fat(fs, fd);
fs->root = dot[0];
fs->root.name[0] = ' ';
if (fs->fatsz == 32) {
fs->root.clus[0] = fs->rdcl & 0xff;
fs->root.clus[1] = (fs->rdcl >> 8) & 0xff;
fs->root.dex.h_clus[0] = (fs->rdcl >> 16) & 0xff;
fs->root.dex.h_clus[1] = (fs->rdcl >> 24) & 0xff;
}
/*
* Mount DOS filesystem
*/
static int
dos_mount(DOS_FS *fs, struct open_file *fd)
{
int err;
uchar_t *buf;
bzero(fs, sizeof (DOS_FS));
fs->fd = fd;
if ((buf = malloc(secbyt(1))) == NULL)
return (errno);
if ((err = ioget(fs->fd, 0, buf, secbyt(1))) ||
(err = parsebs(fs, (DOS_BS *)buf))) {
free(buf);
return (err);
}
free(buf);
if ((fs->fatbuf = malloc(FATBLKSZ)) == NULL)
return (errno);
err = dos_read_fatblk(fs, fd, 0);
if (err != 0) {
free(fs->fatbuf);
return (err);
}
fs->root = dot[0];
fs->root.name[0] = ' ';
if (fs->fatsz == 32) {
fs->root.clus[0] = fs->rdcl & 0xff;
fs->root.clus[1] = (fs->rdcl >> 8) & 0xff;
fs->root.dex.h_clus[0] = (fs->rdcl >> 16) & 0xff;
fs->root.dex.h_clus[1] = (fs->rdcl >> 24) & 0xff;
}
static void
dos_read_fat(DOS_FS *fs, struct open_file *fd)
{
struct devdesc *dd = fd->f_devdata;
if (fat.buf != NULL) { /* can we reuse old buffer? */
if (fat.size != fs->spf) {
free(fat.buf); /* no, free old buffer */
fat.buf = NULL;
}
}
if (fat.buf == NULL)
fat.buf = malloc(secbyt(fs->spf));
if (fat.buf != NULL) {
if (ioget(fd, fs->lsnfat, 0, fat.buf, secbyt(fs->spf)) == 0) {
fat.size = fs->spf;
fat.unit = dd->d_unit;
return;
}
}
if (fat.buf != NULL) /* got IO error */
free(fat.buf);
fat.buf = NULL;
fat.unit = -1; /* impossible unit */
fat.size = 0;
}
static int
dos_read_fatblk(DOS_FS *fs, struct open_file *fd, uint_t blknum)
{
int err;
size_t io_size;
daddr_t offset_in_fat, max_offset_in_fat;
offset_in_fat = ((daddr_t)blknum) * FATBLKSZ;
max_offset_in_fat = secbyt(fs->spf);
io_size = FATBLKSZ;
if (offset_in_fat > max_offset_in_fat)
offset_in_fat = max_offset_in_fat;
if (offset_in_fat + io_size > max_offset_in_fat)
io_size = ((size_t)(max_offset_in_fat - offset_in_fat));
if (io_size != 0) {
err = ioget(fd, fs->lsnfat + bytsec(offset_in_fat),
fs->fatbuf, io_size);
if (err != 0) {
fs->fatbuf_blknum = ((uint_t)(-1));
return (err);
}
}
if (io_size < FATBLKSZ)
memset(fs->fatbuf + io_size, 0, FATBLKSZ - io_size);
fs->fatbuf_blknum = blknum;
return (0);
}
/*
* Mount DOS filesystem
*/
static int
dos_mount(DOS_FS *fs, struct open_file *fd)
{
int err;
bzero(fs, sizeof(DOS_FS));
fs->fd = fd;
if ((err = !(fs->buf = malloc(SECSIZ)) ? errno : 0) ||
(err = ioget(fs->fd, 0, fs->buf, 1)) ||
(err = parsebs(fs, (DOS_BS *)fs->buf))) {
(void)dosunmount(fs);
return(err);
}
fs->root = dot[0];
fs->root.name[0] = ' ';
if (fs->fatsz == 32) {
fs->root.clus[0] = fs->rdcl & 0xff;
fs->root.clus[1] = (fs->rdcl >> 8) & 0xff;
fs->root.dex.h_clus[0] = (fs->rdcl >> 16) & 0xff;
fs->root.dex.h_clus[1] = (fs->rdcl >> 24) & 0xff;
}
