201 lines
4.9 KiB
Python
201 lines
4.9 KiB
Python
# Implement (a subset of) Sun XDR -- RFC1014.
|
|
|
|
|
|
try:
|
|
import struct
|
|
except ImportError:
|
|
struct = None
|
|
|
|
|
|
Long = type(0L)
|
|
|
|
|
|
class Packer:
|
|
|
|
def __init__(self):
|
|
self.reset()
|
|
|
|
def reset(self):
|
|
self.buf = ''
|
|
|
|
def get_buf(self):
|
|
return self.buf
|
|
|
|
def pack_uint(self, x):
|
|
self.buf = self.buf + \
|
|
(chr(int(x>>24 & 0xff)) + chr(int(x>>16 & 0xff)) + \
|
|
chr(int(x>>8 & 0xff)) + chr(int(x & 0xff)))
|
|
if struct and struct.pack('l', 1) == '\0\0\0\1':
|
|
def pack_uint(self, x):
|
|
if type(x) == Long:
|
|
x = int((x + 0x80000000L) % 0x100000000L \
|
|
- 0x80000000L)
|
|
self.buf = self.buf + struct.pack('l', x)
|
|
|
|
pack_int = pack_uint
|
|
|
|
pack_enum = pack_int
|
|
|
|
def pack_bool(self, x):
|
|
if x: self.buf = self.buf + '\0\0\0\1'
|
|
else: self.buf = self.buf + '\0\0\0\0'
|
|
|
|
def pack_uhyper(self, x):
|
|
self.pack_uint(int(x>>32 & 0xffffffff))
|
|
self.pack_uint(int(x & 0xffffffff))
|
|
|
|
pack_hyper = pack_uhyper
|
|
|
|
def pack_float(self, x):
|
|
# XXX
|
|
self.buf = self.buf + struct.pack('f', x)
|
|
|
|
def pack_double(self, x):
|
|
# XXX
|
|
self.buf = self.buf + struct.pack('d', x)
|
|
|
|
def pack_fstring(self, n, s):
|
|
if n < 0:
|
|
raise ValueError, 'fstring size must be nonnegative'
|
|
n = ((n+3)/4)*4
|
|
data = s[:n]
|
|
data = data + (n - len(data)) * '\0'
|
|
self.buf = self.buf + data
|
|
|
|
pack_fopaque = pack_fstring
|
|
|
|
def pack_string(self, s):
|
|
n = len(s)
|
|
self.pack_uint(n)
|
|
self.pack_fstring(n, s)
|
|
|
|
pack_opaque = pack_string
|
|
|
|
def pack_list(self, list, pack_item):
|
|
for item in list:
|
|
self.pack_uint(1)
|
|
pack_item(item)
|
|
self.pack_uint(0)
|
|
|
|
def pack_farray(self, n, list, pack_item):
|
|
if len(list) <> n:
|
|
raise ValueError, 'wrong array size'
|
|
for item in list:
|
|
pack_item(item)
|
|
|
|
def pack_array(self, list, pack_item):
|
|
n = len(list)
|
|
self.pack_uint(n)
|
|
self.pack_farray(n, list, pack_item)
|
|
|
|
|
|
class Unpacker:
|
|
|
|
def __init__(self, data):
|
|
self.reset(data)
|
|
|
|
def reset(self, data):
|
|
self.buf = data
|
|
self.pos = 0
|
|
|
|
def done(self):
|
|
if self.pos < len(self.buf):
|
|
raise RuntimeError, 'unextracted data remains'
|
|
|
|
def unpack_uint(self):
|
|
i = self.pos
|
|
self.pos = j = i+4
|
|
data = self.buf[i:j]
|
|
if len(data) < 4:
|
|
raise EOFError
|
|
x = long(ord(data[0]))<<24 | ord(data[1])<<16 | \
|
|
ord(data[2])<<8 | ord(data[3])
|
|
# Return a Python long only if the value is not representable
|
|
# as a nonnegative Python int
|
|
if x < 0x80000000L: x = int(x)
|
|
return x
|
|
if struct and struct.unpack('l', '\0\0\0\1') == 1:
|
|
def unpack_uint(self):
|
|
i = self.pos
|
|
self.pos = j = i+4
|
|
data = self.buf[i:j]
|
|
if len(data) < 4:
|
|
raise EOFError
|
|
return struct.unpack('l', data)
|
|
|
|
def unpack_int(self):
|
|
x = self.unpack_uint()
|
|
if x >= 0x80000000L: x = x - 0x100000000L
|
|
return int(x)
|
|
|
|
unpack_enum = unpack_int
|
|
|
|
unpack_bool = unpack_int
|
|
|
|
def unpack_uhyper(self):
|
|
hi = self.unpack_uint()
|
|
lo = self.unpack_uint()
|
|
return long(hi)<<32 | lo
|
|
|
|
def unpack_hyper(self):
|
|
x = self.unpack_uhyper()
|
|
if x >= 0x8000000000000000L: x = x - 0x10000000000000000L
|
|
return x
|
|
|
|
def unpack_float(self):
|
|
# XXX
|
|
i = self.pos
|
|
self.pos = j = i+4
|
|
data = self.buf[i:j]
|
|
if len(data) < 4:
|
|
raise EOFError
|
|
return struct.unpack('f', data)[0]
|
|
|
|
def unpack_double(self):
|
|
# XXX
|
|
i = self.pos
|
|
self.pos = j = i+8
|
|
data = self.buf[i:j]
|
|
if len(data) < 8:
|
|
raise EOFError
|
|
return struct.unpack('d', data)[0]
|
|
|
|
def unpack_fstring(self, n):
|
|
if n < 0:
|
|
raise ValueError, 'fstring size must be nonnegative'
|
|
i = self.pos
|
|
j = i + (n+3)/4*4
|
|
if j > len(self.buf):
|
|
raise EOFError
|
|
self.pos = j
|
|
return self.buf[i:i+n]
|
|
|
|
unpack_fopaque = unpack_fstring
|
|
|
|
def unpack_string(self):
|
|
n = self.unpack_uint()
|
|
return self.unpack_fstring(n)
|
|
|
|
unpack_opaque = unpack_string
|
|
|
|
def unpack_list(self, unpack_item):
|
|
list = []
|
|
while 1:
|
|
x = self.unpack_uint()
|
|
if x == 0: break
|
|
if x <> 1:
|
|
raise RuntimeError, '0 or 1 expected, got %r' % (x, )
|
|
item = unpack_item()
|
|
list.append(item)
|
|
return list
|
|
|
|
def unpack_farray(self, n, unpack_item):
|
|
list = []
|
|
for i in range(n):
|
|
list.append(unpack_item())
|
|
return list
|
|
|
|
def unpack_array(self, unpack_item):
|
|
n = self.unpack_uint()
|
|
return self.unpack_farray(n, unpack_item)
|