def recover_disk(base_disk, base_mem, overlay_mem, overlay_disk, recover_path, chunk_size):
recover_fd = open(recover_path, "wb")
# get delta list from file and recover it to origin
delta_stream = open(overlay_disk, "r")
recovered_memory = Recovered_delta(base_disk, base_mem, chunk_size, \
parent=base_disk, overlay_memory=overlay_mem)
for delta_item in DeltaList.from_stream(delta_stream):
recovered_memory.recover_item(delta_item)
delta_list = recovered_memory.delta_list
# overlay map
chunk_list = []
# sort delta list using offset
delta_list.sort(key=itemgetter('offset'))
for delta_item in delta_list:
if len(delta_item.data) != chunk_size:
raise DiskError("recovered size is not same as page size")
chunk_list.append("%ld:1" % (delta_item.offset/chunk_size))
recover_fd.seek(delta_item.offset)
recover_fd.write(delta_item.data)
last_write_offset = delta_item.offset + len(delta_item.data)
# fill zero to the end of the modified file
if last_write_offset:
diff_offset = os.path.getsize(base_disk) - last_write_offset
if diff_offset > 0:
recover_fd.seek(diff_offset-1, os.SEEK_CUR)
recover_fd.write('0')
recover_fd.close()
# overlay chunk format: chunk_1:1,chunk_2:1,...
return ','.join(chunk_list)
def recover_disk(base_disk, base_mem, overlay_mem, overlay_disk, recover_path,
chunk_size):
recover_fd = open(recover_path, "wb")
# get delta list from file and recover it to origin
delta_stream = open(overlay_disk, "r")
recovered_memory = Recovered_delta(base_disk, base_mem, chunk_size, \
parent=base_disk, overlay_memory=overlay_mem)
for delta_item in DeltaList.from_stream(delta_stream):
recovered_memory.recover_item(delta_item)
delta_list = recovered_memory.delta_list
# overlay map
chunk_list = []
# sort delta list using offset
delta_list.sort(key=itemgetter('offset'))
for delta_item in delta_list:
if len(delta_item.data) != chunk_size:
raise DiskError("recovered size is not same as page size")
chunk_list.append("%ld:1" % (delta_item.offset / chunk_size))
recover_fd.seek(delta_item.offset)
recover_fd.write(delta_item.data)
last_write_offset = delta_item.offset + len(delta_item.data)
# fill zero to the end of the modified file
if last_write_offset:
diff_offset = os.path.getsize(base_disk) - last_write_offset
if diff_offset > 0:
recover_fd.seek(diff_offset - 1, os.SEEK_CUR)
recover_fd.write('0')
recover_fd.close()
# overlay chunk format: chunk_1:1,chunk_2:1,...
return ','.join(chunk_list)
