2 from __future__ import absolute_import
5 from bup import options
6 from bup.compat import argv_bytes, bytes_from_uint
7 from bup.helpers import log
8 from bup.io import path_msg
12 return b''.join(bytes_from_uint(random.randrange(0,256)) for i in range(n))
16 bup damage [-n count] [-s maxsize] [-S seed] <filenames...>
18 WARNING: THIS COMMAND IS EXTREMELY DANGEROUS
19 n,num= number of blocks to damage
20 s,size= maximum size of each damaged block
21 percent= maximum size of each damaged block (as a percent of entire file)
22 equal spread damage evenly throughout the file
23 S,seed= random number seed (for repeatable tests)
27 o = options.Options(optspec)
28 opt, flags, extra = o.parse_bytes(argv[1:])
31 o.fatal('filenames expected')
37 name = argv_bytes(name)
38 log('Damaging "%s"...\n' % path_msg(name))
39 with open(name, 'r+b') as f:
40 st = os.fstat(f.fileno())
42 if opt.percent or opt.size:
43 ms1 = int(float(opt.percent or 0)/100.0*size) or size
44 ms2 = opt.size or size
45 maxsize = min(ms1, ms2)
48 chunks = opt.num or 10
49 chunksize = size // chunks
50 for r in range(chunks):
51 sz = random.randrange(1, maxsize+1)
57 ofs = random.randrange(0, size - sz + 1)
58 log(' %6d bytes at %d\n' % (sz, ofs))
60 f.write(randblock(sz))