+class limitreader(object):
+ def __init__(self, back, limit):
+ self.bk = back
+ self.limit = limit
+ self.rb = 0
+ self.buf = bytearray()
+
+ def close(self):
+ pass
+
+ def read(self, size=-1):
+ ra = self.limit - self.rb
+ if size >= 0:
+ ra = min(ra, size)
+ while len(self.buf) < ra:
+ ret = self.bk.read(ra - len(self.buf))
+ if ret == b"":
+ raise IOError("Unexpected EOF")
+ self.buf.extend(ret)
+ self.rb += len(ret)
+ ret = bytes(self.buf[:ra])
+ self.buf = self.buf[ra:]
+ return ret
+
+ def readline(self, size=-1):
+ off = 0
+ while True:
+ p = self.buf.find(b'\n', off)
+ if p >= 0:
+ ret = bytes(self.buf[:p + 1])
+ self.buf = self.buf[p + 1:]
+ return ret
+ off = len(self.buf)
+ if size >= 0 and len(self.buf) >= size:
+ ret = bytes(self.buf[:size])
+ self.buf = self.buf[size:]
+ return ret
+ if self.rb == self.limit:
+ ret = bytes(self.buf)
+ self.buf = bytearray()
+ return ret
+ ra = self.limit - self.rb
+ if size >= 0:
+ ra = min(ra, size)
+ ra = min(ra, 1024)
+ ret = self.bk.read(ra)
+ if ret == b"":
+ raise IOError("Unpexpected EOF")
+ self.buf.extend(ret)
+ self.rb += len(ret)
+
+ def readlines(self, hint=None):
+ return list(self)
+
+ def __iter__(rd):
+ class lineiter(object):
+ def __iter__(self):
+ return self
+ def __next__(self):
+ ret = rd.readline()
+ if ret == b"":
+ raise StopIteration()
+ return ret
+ return lineiter()
+