def create(self):
# create data and preset with 0xff
self.bitmap_data = ctypes.create_string_buffer(
self.bitmap_all_blk_bytes)
for i in xrange(self.bitmap_all_blk_bytes):
self.bitmap_data[i] = chr(0xff)
# clear bit for root block
blk_pos = self.root_blk.blk_num
self.clr_bit(blk_pos)
blk_pos += 1
# create ext blocks
for i in xrange(self.num_ext):
bm_ext = BitmapExtBlock(self.blkdev, blk_pos)
bm_ext.create()
self.clr_bit(blk_pos)
blk_pos += 1
self.ext_blks.append(bm_ext)
# create bitmap blocks
for i in xrange(self.bitmap_num_blks):
bm = BitmapBlock(self.blkdev, blk_pos)
bm.create()
self.clr_bit(blk_pos)
blk_pos += 1
self.bitmap_blks.append(bm)
# set pointers to ext blocks
if self.num_ext > 0:
self.root_blk.bitmap_ext_blk = self.ext_blks[0].blk_num
for i in xrange(self.num_ext) - 1:
bm_ext = self.ext_blks[i]
bm_ext_next = self.ext_blks[i + 1]
bm_ext.bitmap_ext_blk = bm_ext_next.blk_num
# set pointers to bitmap blocks
cur_ext_index = 0
cur_ext_pos = 0
for i in xrange(self.bitmap_num_blks):
blk_num = self.bitmap_blks[i].blk_num
if i < self.num_blks_in_root:
# pointers in root block
self.root_blk.bitmap_ptrs[i] = blk_num
else:
# pointers in ext block
self.ext_blks[cur_ext_index].bitmap_ptrs[cur_ext_pos] = blk_num
cur_ext_pos += 1
if cur_ext_pos == self.num_blks_in_ext:
cur_ext_pos = 0
cur_ext_index += 1
self.valid = True
def create(self):
# create data and preset with 0xff
self.bitmap_data = ctypes.create_string_buffer(self.bitmap_all_blk_bytes)
for i in xrange(self.bitmap_all_blk_bytes):
self.bitmap_data[i] = chr(0xff)
# clear bit for root block
blk_pos = self.root_blk.blk_num
self.clr_bit(blk_pos)
blk_pos += 1
# create ext blocks
for i in xrange(self.num_ext):
bm_ext = BitmapExtBlock(self.blkdev, blk_pos)
bm_ext.create()
self.clr_bit(blk_pos)
blk_pos += 1
self.ext_blks.append(bm_ext)
# create bitmap blocks
for i in xrange(self.bitmap_num_blks):
bm = BitmapBlock(self.blkdev, blk_pos)
bm.create()
self.clr_bit(blk_pos)
blk_pos += 1
self.bitmap_blks.append(bm)
# set pointers to ext blocks
if self.num_ext > 0:
self.root_blk.bitmap_ext_blk = self.ext_blks[0].blk_num
for i in xrange(self.num_ext)-1:
bm_ext = self.ext_blks[i]
bm_ext_next = self.ext_blks[i+1]
bm_ext.bitmap_ext_blk = bm_ext_next.blk_num
# set pointers to bitmap blocks
cur_ext_index = 0
cur_ext_pos = 0
for i in xrange(self.bitmap_num_blks):
blk_num = self.bitmap_blks[i].blk_num
if i < self.num_blks_in_root:
# pointers in root block
self.root_blk.bitmap_ptrs[i] = blk_num
else:
# pointers in ext block
self.ext_blks[cur_ext_index].bitmap_ptrs[cur_ext_pos] = blk_num
cur_ext_pos += 1
if cur_ext_pos == self.num_blks_in_ext:
cur_ext_pos = 0
cur_ext_index += 1
self.valid = True
def read(self):
self.bitmap_blks = []
bitmap_data = ""
# get bitmap blocks from root block
blocks = self.root_blk.bitmap_ptrs
for blk in blocks:
if blk == 0:
break
bm = BitmapBlock(self.blkdev, blk)
bm.read()
if not bm.valid:
raise FSError(INVALID_BITMAP_BLOCK, block=bm)
self.bitmap_blks.append(bm)
bitmap_data += bm.get_bitmap_data()
# now check extended bitmap blocks
ext_blk = self.root_blk.bitmap_ext_blk
while ext_blk != 0:
bm_ext = BitmapExtBlock(self.blkdev, ext_blk)
bm_ext.read()
self.ext_blks.append(bm_ext)
blocks = bm_ext.bitmap_ptrs
for blk in blocks:
if blk == 0:
break
bm = BitmapBlock(self.blkdev, blk)
bm.read()
if not bm.valid:
raise FSError(INVALID_BITMAP_BLOCK, block=bm)
bitmap_data += bm.get_bitmap_data()
self.bitmap_blks.append(bm)
ext_blk = bm_ext.bitmap_ext_blk
# check bitmap data
num_bm_blks = len(self.bitmap_blks)
num_bytes = self.bitmap_blk_bytes * num_bm_blks
if num_bytes != len(bitmap_data):
raise FSError(BITMAP_SIZE_MISMATCH,
node=self,
extra="got=%d want=%d" %
(len(bitmap_data), num_bytes))
if num_bm_blks != self.bitmap_num_blks:
raise FSError(BITMAP_BLOCK_COUNT_MISMATCH,
node=self,
extra="got=%d want=%d" %
(self.bitmap_num_blks, num_bm_blks))
# create a modyfiable bitmap
self.bitmap_data = ctypes.create_string_buffer(bitmap_data)
self.valid = True
def read(self):
self.bitmap_blks = []
bitmap_data = ""
# get bitmap blocks from root block
blocks = self.root_blk.bitmap_ptrs
for blk in blocks:
if blk == 0:
break
bm = BitmapBlock(self.blkdev, blk)
bm.read()
if not bm.valid:
raise FSError(INVALID_BITMAP_BLOCK, block=bm)
self.bitmap_blks.append(bm)
bitmap_data += bm.get_bitmap_data()
# now check extended bitmap blocks
ext_blk = self.root_blk.bitmap_ext_blk
while ext_blk != 0:
bm_ext = BitmapExtBlock(self.blkdev, ext_blk)
bm_ext.read()
self.ext_blks.append(bm_ext)
blocks = bm_ext.bitmap_ptrs
for blk in blocks:
if blk == 0:
break
bm = BitmapBlock(self.blkdev, blk)
bm.read()
if not bm.valid:
raise FSError(INVALID_BITMAP_BLOCK, block=bm)
bitmap_data += bm.get_bitmap_data()
self.bitmap_blks.append(bm)
ext_blk = bm_ext.bitmap_ext_blk
# check bitmap data
num_bm_blks = len(self.bitmap_blks)
num_bytes = self.bitmap_blk_bytes * num_bm_blks
if num_bytes != len(bitmap_data):
raise FSError(BITMAP_SIZE_MISMATCH, node=self, extra="got=%d want=%d" % (len(bitmap_data), num_bytes))
if num_bm_blks != self.bitmap_num_blks:
raise FSError(BITMAP_BLOCK_COUNT_MISMATCH, node=self, extra="got=%d want=%d" % (self.bitmap_num_blks, num_bm_blks))
# create a modyfiable bitmap
self.bitmap_data = ctypes.create_string_buffer(bitmap_data)
self.valid = True