SHEEP server can still crash in some situations

[nbarlowATI]

In particular when setting parameters or input values...
One example, to reproduce:

• run run-sheep-server executable
• in separate terminal,

export SHEEP_HOME=/path/to/SHEEP/pysheep
cd $SHEEP_HOME
python

then in python:

import os
from pysheep.interface import sheep_client sheep_client.set_circuit(os.environ["SHEEP_HOME"]+"/benchmark_inputs/low_level/circuits/circuit-ADDCONSTANT-1.sheep")
sheep_client.set_const_inputs({"c_input_0": 5})
sheep_client.set_circuit(os.environ["SHEEP_HOME"]+"/benchmark_inputs/low_level/circuits/circuit-ADD-1.sheep")
sheep_client.set_const_inputs({})

[ots22]

The above example seems to work correctly now.

#198 should fix most of the server crashes we see in general (which are usually caused when a call to an HE library aborts). Now returns status 500 with an appropriate message.