/*
* NAME: file->addextent()
* DESCRIPTION: add an extent to a file
*/
int f_addextent(hfsfile *file, ExtDescriptor *blocks)
{
hfsvol *vol = file->vol;
ExtDataRec *extrec;
ULongInt *pylen;
unsigned int start, end;
node n;
int i;
f_getptrs(file, &extrec, 0, &pylen);
start = file->fabn;
end = *pylen / vol->mdb.drAlBlkSiz;
n.nnum = 0;
i = -1;
while (start < end)
{
for (i = 0; i < 3; ++i)
{
unsigned int num;
num = file->ext[i].xdrNumABlks;
start += num;
if (start == end)
break;
else if (start > end)
ERROR(EIO, "file extents exceed file physical length");
else if (num == 0)
ERROR(EIO, "empty file extent");
}
if (start == end)
break;
if (v_extsearch(file, start, &file->ext, &n) <= 0)
goto fail;
file->fabn = start;
}
if (i >= 0 &&
file->ext[i].xdrStABN + file->ext[i].xdrNumABlks == blocks->xdrStABN)
file->ext[i].xdrNumABlks += blocks->xdrNumABlks;
else
{
/* create a new extent descriptor */
if (++i < 3)
file->ext[i] = *blocks;
else
{
ExtKeyRec key;
byte record[HFS_MAX_EXTRECLEN];
unsigned int reclen;
/* record is full; create a new one */
file->ext[0] = *blocks;
for (i = 1; i < 3; ++i)
{
file->ext[i].xdrStABN = 0;
file->ext[i].xdrNumABlks = 0;
}
file->fabn = start;
r_makeextkey(&key, file->fork, file->cat.u.fil.filFlNum, end);
r_packextrec(&key, &file->ext, record, &reclen);
if (bt_insert(&vol->ext, record, reclen) == -1)
goto fail;
i = -1;
}
}
if (i >= 0)
{
/* store the modified extent record */
if (file->fabn)
{
if ((n.nnum == 0 &&
v_extsearch(file, file->fabn, 0, &n) <= 0) ||
v_putextrec(&file->ext, &n) == -1)
goto fail;
}
else
memcpy(extrec, &file->ext, sizeof(ExtDataRec));
}
*pylen += blocks->xdrNumABlks * vol->mdb.drAlBlkSiz;
file->flags |= HFS_FILE_UPDATE_CATREC;
return 0;
fail:
return -1;
}
/*
* NAME: file->trunc()
* DESCRIPTION: release allocation blocks unneeded by a file
*/
int f_trunc(hfsfile *file)
{
hfsvol *vol = file->vol;
ExtDataRec *extrec;
ULongInt *lglen, *pylen, alblksz, newpylen;
unsigned int dlen, start, end;
node n;
int i;
if (vol->flags & HFS_VOL_READONLY)
goto done;
f_getptrs(file, &extrec, &lglen, &pylen);
alblksz = vol->mdb.drAlBlkSiz;
newpylen = (*lglen / alblksz + (*lglen % alblksz != 0)) * alblksz;
if (newpylen > *pylen)
ERROR(EIO, "file size exceeds physical length");
else if (newpylen == *pylen)
goto done;
dlen = (*pylen - newpylen) / alblksz;
start = file->fabn;
end = newpylen / alblksz;
if (start >= end)
{
start = file->fabn = 0;
memcpy(&file->ext, extrec, sizeof(ExtDataRec));
}
n.nnum = 0;
i = -1;
while (start < end)
{
for (i = 0; i < 3; ++i)
{
unsigned int num;
num = file->ext[i].xdrNumABlks;
start += num;
if (start >= end)
break;
else if (num == 0)
ERROR(EIO, "empty file extent");
}
if (start >= end)
break;
if (v_extsearch(file, start, &file->ext, &n) <= 0)
goto fail;
file->fabn = start;
}
if (start > end)
{
ExtDescriptor blocks;
file->ext[i].xdrNumABlks -= start - end;
dlen -= start - end;
blocks.xdrStABN = file->ext[i].xdrStABN + file->ext[i].xdrNumABlks;
blocks.xdrNumABlks = start - end;
if (v_freeblocks(vol, &blocks) == -1)
goto fail;
}
*pylen = newpylen;
file->flags |= HFS_FILE_UPDATE_CATREC;
do
{
while (dlen && ++i < 3)
{
unsigned int num;
num = file->ext[i].xdrNumABlks;
start += num;
if (num == 0)
ERROR(EIO, "empty file extent");
else if (num > dlen)
ERROR(EIO, "file extents exceed physical size");
dlen -= num;
if (v_freeblocks(vol, &file->ext[i]) == -1)
goto fail;
file->ext[i].xdrStABN = 0;
file->ext[i].xdrNumABlks = 0;
}
if (file->fabn)
{
if (n.nnum == 0 &&
v_extsearch(file, file->fabn, 0, &n) <= 0)
goto fail;
if (file->ext[0].xdrNumABlks)
{
if (v_putextrec(&file->ext, &n) == -1)
goto fail;
}
else
{
if (bt_delete(&vol->ext, HFS_NODEREC(n, n.rnum)) == -1)
goto fail;
n.nnum = 0;
}
}
else
memcpy(extrec, &file->ext, sizeof(ExtDataRec));
if (dlen)
{
if (v_extsearch(file, start, &file->ext, &n) <= 0)
goto fail;
file->fabn = start;
i = -1;
}
}
while (dlen);
done:
return 0;
fail:
return -1;
}
/*
* NAME: file->alloc()
* DESCRIPTION: reserve disk blocks for a file
*/
int f_alloc(hfsfile *file)
{
hfsvol *vol = file->vol;
ExtDescriptor blocks;
ExtDataRec *extrec;
unsigned long *pylen, clumpsz;
unsigned int start, end;
node n;
int i;
clumpsz = file->clump;
if (clumpsz == 0)
clumpsz = vol->mdb.drClpSiz;
blocks.xdrNumABlks = clumpsz / vol->mdb.drAlBlkSiz;
if (v_allocblocks(vol, &blocks) < 0)
return -1;
/* update the file's extents */
f_getptrs(file, 0, &pylen, &extrec);
start = file->fabn;
end = *pylen / vol->mdb.drAlBlkSiz;
n.nnum = 0;
i = -1;
while (start < end)
{
for (i = 0; i < 3; ++i)
{
unsigned int num;
num = file->ext[i].xdrNumABlks;
start += num;
if (start == end)
break;
else if (start > end)
{
v_freeblocks(vol, &blocks);
ERROR(EIO, "file extents exceed file physical length");
return -1;
}
else if (num == 0)
{
v_freeblocks(vol, &blocks);
ERROR(EIO, "empty file extent");
return -1;
}
}
if (start == end)
break;
if (v_extsearch(file, start, &file->ext, &n) <= 0)
{
v_freeblocks(vol, &blocks);
return -1;
}
file->fabn = start;
}
if (i >= 0 &&
file->ext[i].xdrStABN + file->ext[i].xdrNumABlks == blocks.xdrStABN)
file->ext[i].xdrNumABlks += blocks.xdrNumABlks;
else
{
/* create a new extent descriptor */
if (++i < 3)
file->ext[i] = blocks;
else
{
ExtKeyRec key;
unsigned char record[HFS_EXTRECMAXLEN];
int reclen;
/* record is full; create a new one */
file->ext[0] = blocks;
for (i = 1; i < 3; ++i)
{
file->ext[i].xdrStABN = 0;
file->ext[i].xdrNumABlks = 0;
}
file->fabn = start;
r_makeextkey(&key, file->fork, file->cat.u.fil.filFlNum, end);
r_packextkey(&key, record, &reclen);
r_packextdata(&file->ext, HFS_RECDATA(record), &reclen);
if (bt_insert(&vol->ext, record, reclen) < 0)
{
v_freeblocks(vol, &blocks);
return -1;
}
i = -1;
}
}
if (i >= 0)
{
/* store the modified extent record */
if (file->fabn)
{
if ((n.nnum == 0 &&
v_extsearch(file, file->fabn, 0, &n) <= 0) ||
v_putextrec(&file->ext, &n) < 0)
{
v_freeblocks(vol, &blocks);
return -1;
}
}
else
memcpy(extrec, file->ext, sizeof(ExtDataRec));
}
*pylen += blocks.xdrNumABlks * vol->mdb.drAlBlkSiz;
file->flags |= HFS_UPDATE_CATREC;
return blocks.xdrNumABlks;
}
