def _encode_file_stringy_easyfec(N):
filefec.encode_file_stringy_easyfec(open(FNAME, "rb"), donothing, K, M)
def encode_to_files(inf, fsize, dirname, prefix, k, m, suffix=".fec", overwrite=False, verbose=False):
"""
Encode inf, writing the shares to specially named, newly created files.
@param fsize: calling read() on inf must yield fsize bytes of data and
then raise an EOFError
@param dirname: the name of the directory into which the sharefiles will
be written
"""
mlen = len(str(m))
format = FORMAT_FORMAT % (mlen, mlen,)
padbytes = pad_size(fsize, k)
fns = []
fs = []
try:
for shnum in range(m):
hdr = filefec._build_header(m, k, padbytes, shnum)
fn = os.path.join(dirname, format % (prefix, shnum, m, suffix,))
if verbose:
print "Creating share file %r..." % (fn,)
if overwrite:
f = open(fn, "wb")
else:
flags = os.O_WRONLY|os.O_CREAT|os.O_EXCL | (hasattr(os,
'O_BINARY') and os.O_BINARY)
fd = os.open(fn, flags)
f = os.fdopen(fd, "wb")
f.write(hdr)
fs.append(f)
fns.append(fn)
sumlen = [0]
def cb(blocks, length):
assert len(blocks) == len(fs)
oldsumlen = sumlen[0]
sumlen[0] += length
if verbose:
if int((float(oldsumlen) / fsize) * 10) \
!= int((float(sumlen[0]) / fsize) * 10):
print str(int((float(sumlen[0]) / fsize) * 10) * 10) \
+ "% ...",
if sumlen[0] > fsize:
raise IOError("Wrong file size -- possibly the size of the"
" file changed during encoding. Original size: %d,"
" observed size at least: %s" % (fsize, sumlen[0],))
for i in range(len(blocks)):
data = blocks[i]
fs[i].write(data)
length -= len(data)
filefec.encode_file_stringy_easyfec(inf, cb, k, m, chunksize=4096)
except EnvironmentError, le:
print "Cannot complete because of exception: "
print le
print "Cleaning up..."
# clean up
while fs:
f = fs.pop()
f.close() ; del f
fn = fns.pop()
if verbose:
print "Cleaning up: trying to remove %r..." % (fn,)
fileutil.remove_if_possible(fn)
return None
