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_memory(base_disk, base_mem, delta_path, out_path, verify_with_original=None):
# Recover modified memory snapshot
# base_path: base memory snapshot, delta pages will be applied over it
# delta_path: memory overlay
# out_path: path to recovered modified memory snapshot
# verify_with_original: original modification file for recover verification
recovered_memory = Recovered_delta(base_disk, base_mem, delta_path, out_path, \
Memory.RAM_PAGE_SIZE, parent=base_mem)
chunk_list = []
for chunk_number in recovered_memory.recover_chunks():
chunk_list.append("%ld:1" % chunk_number)
recovered_memory.finish()
# varify with original
if verify_with_original:
modi_mem = open(verify_with_original, "rb")
base_file = open(base_mem, "rb")
delta_list_index = 0
while True:
offset = base_file.tell()
if len(delta_list) == delta_list_index:
break
base_data = base_file.read(Memory.RAM_PAGE_SIZE)
if offset != delta_list[delta_list_index].offset:
#LOG.debug("from base data: %d" % len(base_data))
modi_mem.seek(offset)
modi_data = modi_mem.read(len(base_data))
if modi_data != base_data:
msg = "orignal data is not same at %ld" % offset
raise MemoryError(msg)
else:
modi_mem.seek(offset)
recover_data = delta_list[delta_list_index].data
origin_data = modi_mem.read(len(recover_data))
#LOG.debug("from recovered data: %d at %ld" % (len(recover_data), delta_list[delta_list_index].offset))
delta_list_index += 1
if recover_data != origin_data:
msg = "orignal data is not same at %ld" % offset
raise MemoryError(msg)
for delta_item in delta_list:
offset = delta_item.offset
data = delta_item.data
modi_mem.seek(offset)
origin_data = modi_mem.read(len(data))
if data != origin_data:
msg = "orignal data is not same at %ld" % offset
raise MemoryError(msg)
LOG.debug("Pass all varification - Successfully recovered")
return ','.join(chunk_list)
