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Diffstat (limited to 'lib-python/3/xdrlib.py')
-rw-r--r--lib-python/3/xdrlib.py228
1 files changed, 228 insertions, 0 deletions
diff --git a/lib-python/3/xdrlib.py b/lib-python/3/xdrlib.py
new file mode 100644
index 0000000000..4e48677040
--- /dev/null
+++ b/lib-python/3/xdrlib.py
@@ -0,0 +1,228 @@
+"""Implements (a subset of) Sun XDR -- eXternal Data Representation.
+
+See: RFC 1014
+
+"""
+
+import struct
+from io import BytesIO
+
+__all__ = ["Error", "Packer", "Unpacker", "ConversionError"]
+
+# exceptions
+class Error(Exception):
+ """Exception class for this module. Use:
+
+ except xdrlib.Error, var:
+ # var has the Error instance for the exception
+
+ Public ivars:
+ msg -- contains the message
+
+ """
+ def __init__(self, msg):
+ self.msg = msg
+ def __repr__(self):
+ return repr(self.msg)
+ def __str__(self):
+ return str(self.msg)
+
+
+class ConversionError(Error):
+ pass
+
+
+
+class Packer:
+ """Pack various data representations into a buffer."""
+
+ def __init__(self):
+ self.reset()
+
+ def reset(self):
+ self.__buf = BytesIO()
+
+ def get_buffer(self):
+ return self.__buf.getvalue()
+ # backwards compatibility
+ get_buf = get_buffer
+
+ def pack_uint(self, x):
+ self.__buf.write(struct.pack('>L', x))
+
+ def pack_int(self, x):
+ self.__buf.write(struct.pack('>l', x))
+
+ pack_enum = pack_int
+
+ def pack_bool(self, x):
+ if x: self.__buf.write(b'\0\0\0\1')
+ else: self.__buf.write(b'\0\0\0\0')
+
+ def pack_uhyper(self, x):
+ self.pack_uint(x>>32 & 0xffffffff)
+ self.pack_uint(x & 0xffffffff)
+
+ pack_hyper = pack_uhyper
+
+ def pack_float(self, x):
+ try: self.__buf.write(struct.pack('>f', x))
+ except struct.error as msg:
+ raise ConversionError(msg)
+
+ def pack_double(self, x):
+ try: self.__buf.write(struct.pack('>d', x))
+ except struct.error as msg:
+ raise ConversionError(msg)
+
+ def pack_fstring(self, n, s):
+ if n < 0:
+ raise ValueError('fstring size must be nonnegative')
+ data = s[:n]
+ n = ((n+3)//4)*4
+ data = data + (n - len(data)) * b'\0'
+ self.__buf.write(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
+ pack_bytes = 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:
+ """Unpacks various data representations from the given buffer."""
+
+ def __init__(self, data):
+ self.reset(data)
+
+ def reset(self, data):
+ self.__buf = data
+ self.__pos = 0
+
+ def get_position(self):
+ return self.__pos
+
+ def set_position(self, position):
+ self.__pos = position
+
+ def get_buffer(self):
+ return self.__buf
+
+ def done(self):
+ if self.__pos < len(self.__buf):
+ raise Error('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 = struct.unpack('>L', data)[0]
+ try:
+ return int(x)
+ except OverflowError:
+ return x
+
+ def unpack_int(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)[0]
+
+ unpack_enum = unpack_int
+
+ def unpack_bool(self):
+ return bool(self.unpack_int())
+
+ def unpack_uhyper(self):
+ hi = self.unpack_uint()
+ lo = self.unpack_uint()
+ return int(hi)<<32 | lo
+
+ def unpack_hyper(self):
+ x = self.unpack_uhyper()
+ if x >= 0x8000000000000000:
+ x = x - 0x10000000000000000
+ return x
+
+ def unpack_float(self):
+ 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):
+ 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
+ unpack_bytes = unpack_string
+
+ def unpack_list(self, unpack_item):
+ list = []
+ while 1:
+ x = self.unpack_uint()
+ if x == 0: break
+ if x != 1:
+ raise ConversionError('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)