Unified error raise and kissat license.

Author: haz

nnf/bin/LICENSE.kissat

@@ -0,0 +1,19 @@
+Copyright (c) 2019-2020 Armin Biere, Johannes Kepler University Linz, Austria
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

nnf/kissat.py

@@ -55,9 +55,7 @@ def solve(
             print("Error: Attempting to run the kissat binary on an")
             print("       incompatible system. Consider compiling kissat")
             print("       natively so it is accessible via the command line.")
-            raise RuntimeError("Unable to run kissat.")
-        else:
-            raise RuntimeError("Unrecognized OSError: %d" % err.errno)
+        raise
 
     # Two known exit codes for the solver
     if proc.returncode not in [10, 20]: