__export int open_file(const char *name, int flags, struct com32_filedata *filedata)
{
int rv;
struct file *file;
char mangled_name[FILENAME_MAX];
dprintf("open_file %s\n", name);
mangle_name(mangled_name, name);
rv = searchdir(mangled_name, flags);
if (rv < 0)
return rv;
file = handle_to_file(rv);
if (file->inode->mode != DT_REG) {
_close_file(file);
return -1;
}
filedata->size = file->inode->size;
filedata->blocklg2 = SECTOR_SHIFT(file->fs);
filedata->handle = rv;
return rv;
}
void getfsbytes(com32sys_t *regs)
{
int sectors;
bool have_more;
uint32_t bytes_read;
char *buf;
struct file *file;
uint16_t handle;
handle = regs->esi.w[0];
file = handle_to_file(handle);
sectors = regs->ecx.w[0] >> SECTOR_SHIFT(file->fs);
buf = MK_PTR(regs->es, regs->ebx.w[0]);
bytes_read = file->fs->fs_ops->getfssec(file, buf, sectors, &have_more);
/*
* If we reach EOF, the filesystem driver will have already closed
* the underlying file... this really should be cleaner.
*/
if (!have_more) {
_close_file(file);
regs->esi.w[0] = 0;
}
regs->ecx.l = bytes_read;
}
static struct inode *iso_get_inode(struct fs_info *fs,
const struct iso_dir_entry *de)
{
struct inode *inode = new_iso_inode(fs);
int blktosec = BLOCK_SHIFT(fs) - SECTOR_SHIFT(fs);
if (!inode)
return NULL;
dprintf("Getting inode for: %.*s\n", de->name_len, de->name);
inode->mode = get_inode_mode(de->flags);
inode->size = de->size_le;
PVT(inode)->lba = de->extent_le;
inode->blocks = (inode->size + BLOCK_SIZE(fs) - 1) >> BLOCK_SHIFT(fs);
/* We have a single extent for all data */
inode->next_extent.pstart = (sector_t)de->extent_le << blktosec;
inode->next_extent.len = (sector_t)inode->blocks << blktosec;
return inode;
}
void pm_load_high(com32sys_t *regs)
{
struct fs_info *fs;
uint32_t bytes;
uint32_t zero_mask;
bool have_more;
uint32_t bytes_read;
char *buf, *limit;
struct file *file;
uint32_t sector_mask;
size_t pad;
uint32_t retflags = 0;
bytes = regs->eax.l;
zero_mask = regs->edx.w[0];
buf = (char *)regs->edi.l;
limit = (char *)(regs->ebp.l & ~zero_mask);
file = handle_to_file(regs->esi.w[0]);
fs = file->fs;
sector_mask = SECTOR_SIZE(fs) - 1;
while (bytes) {
uint32_t sectors;
uint32_t chunk;
if (buf + SECTOR_SIZE(fs) > limit) {
/* Can't fit even one more sector in... */
retflags = EFLAGS_OF;
break;
}
chunk = bytes;
if (regs->ebx.w[0]) {
call16((void (*)(void))(size_t)regs->ebx.w[0], &zero_regs, NULL);
chunk = min(chunk, MAX_CHUNK);
}
if (chunk > (((char *)limit - buf) & ~sector_mask))
chunk = ((char *)limit - buf) & ~sector_mask;
sectors = (chunk + sector_mask) >> SECTOR_SHIFT(fs);
bytes_read = fs->fs_ops->getfssec(file, buf, sectors, &have_more);
if (bytes_read > chunk)
bytes_read = chunk;
buf += bytes_read;
bytes -= bytes_read;
if (!have_more) {
/*
* If we reach EOF, the filesystem driver will have already closed
* the underlying file... this really should be cleaner.
*/
_close_file(file);
regs->esi.w[0] = 0;
retflags = EFLAGS_CF;
break;
}
}
pad = (size_t)buf & zero_mask;
if (pad)
memset(buf, 0, pad);
regs->ebx.l = (size_t)buf;
regs->edi.l = (size_t)buf + pad;
set_flags(regs, retflags);
}
uint32_t generic_getfssec(struct file *file, char *buf,
int sectors, bool *have_more)
{
struct inode *inode = file->inode;
struct fs_info *fs = file->fs;
struct disk *disk = fs->fs_dev->disk;
uint32_t bytes_read = 0;
uint32_t bytes_left = inode->size - file->offset;
uint32_t sectors_left =
(bytes_left + SECTOR_SIZE(fs) - 1) >> SECTOR_SHIFT(fs);
uint32_t lsector;
if (sectors > sectors_left)
sectors = sectors_left;
if (!sectors)
return 0;
lsector = file->offset >> SECTOR_SHIFT(fs);
dprintf("Offset: %u lsector: %u\n", file->offset, lsector);
if (lsector < inode->this_extent.lstart ||
lsector >= inode->this_extent.lstart + inode->this_extent.len) {
/* inode->this_extent unusable, maybe next_extent is... */
inode->this_extent = inode->next_extent;
}
if (lsector < inode->this_extent.lstart ||
lsector >= inode->this_extent.lstart + inode->this_extent.len) {
/* Still nothing useful... */
inode->this_extent.lstart = lsector;
inode->this_extent.len = 0;
} else {
/* We have some usable information */
uint32_t delta = lsector - inode->this_extent.lstart;
inode->this_extent.lstart = lsector;
inode->this_extent.len -= delta;
inode->this_extent.pstart
= next_psector(inode->this_extent.pstart, delta);
}
dprintf("this_extent: lstart %u pstart %llu len %u\n",
inode->this_extent.lstart,
inode->this_extent.pstart,
inode->this_extent.len);
while (sectors) {
uint32_t chunk;
size_t len;
while (sectors > inode->this_extent.len) {
if (!inode->next_extent.len ||
inode->next_extent.lstart !=
inode->this_extent.lstart + inode->this_extent.len)
get_next_extent(inode);
if (!inode->this_extent.len) {
/* Doesn't matter if it's contiguous... */
inode->this_extent = inode->next_extent;
if (!inode->next_extent.len) {
sectors = 0; /* Failed to get anything... we're dead */
break;
}
} else if (inode->next_extent.len &&
inode->next_extent.pstart == next_pstart(&inode->this_extent)) {
/* Coalesce extents and loop */
inode->this_extent.len += inode->next_extent.len;
} else {
/* Discontiguous extents */
break;
}
}
dprintf("this_extent: lstart %u pstart %llu len %u\n",
inode->this_extent.lstart,
inode->this_extent.pstart,
inode->this_extent.len);
chunk = min(sectors, inode->this_extent.len);
len = chunk << SECTOR_SHIFT(fs);
dprintf(" I/O: inode %p @ %u start %llu len %u\n",
inode, inode->this_extent.lstart,
inode->this_extent.pstart, chunk);
if (inode->this_extent.pstart == EXTENT_ZERO) {
memset(buf, 0, len);
} else {
disk->rdwr_sectors(disk, buf, inode->this_extent.pstart, chunk, 0);
inode->this_extent.pstart += chunk;
}
buf += len;
sectors -= chunk;
bytes_read += len;
inode->this_extent.lstart += chunk;
inode->this_extent.len -= chunk;
}
bytes_read = min(bytes_read, bytes_left);
file->offset += bytes_read;
if (have_more)
*have_more = bytes_read < bytes_left;
return bytes_read;
}