#!/usr/bin/env python
# Executables.py
#   Copyright (C) 2012 Diamond Light Source, Graeme Winter
#
#   This code is distributed under the BSD license, a copy of which is
#   included in the root directory of this package.
#
# 17 January 2012
#
# A handler for setting the executables to use for processing tasks,
# interfaced to the command line via -executable program=path.

import sys
import os

class _Executables:
    def __init__(self):
        self._executables = { }

    def add(self, executable, path):
        if not os.path.exists(path):
            raise RuntimeError, 'path %s not found' % path
        self._executables[executable] = path
        return

    def get(self, executable):
        return self._executables.get(executable, None)

Executables = _Executables()