config: Add configs scripts used in Learning gem5

Added a new directory in configs (learning_gem5) to hold the scripts that are
used in the book. See http://lowepower.com/jason/learning_gem5/ for a working
copy. For now, only the scripts in Part 1: Getting started with gem5
have been added. A separate patch adds tests for these scripts.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>

configs/common/SimpleOpts.py

@@ -0,0 +1,73 @@
+# -*- coding: utf-8 -*-
+# Copyright (c) 2015 Jason Power
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Jason Power
+
+""" Options wrapper for simple gem5 configuration scripts
+
+This module wraps the optparse class so that we can register options
+from each class instead of only from the configuration script.
+
+"""
+
+# Module-level variable to track if we've called the parse_args function yet
+called_parse_args = False
+
+# For fatal
+import m5
+
+# import the options parser
+from optparse import OptionParser
+
+# add the options we want to be able to control from the command line
+parser = OptionParser()
+
+def add_option(*args, **kwargs):
+    """Call "add_option" to the global options parser
+    """
+
+    if (parser.has_option(args[0]) or
+            (len(args) > 1 and parser.has_option(args[1])) ):
+        m5.fatal("Duplicate option: %s" % str(args))
+
+    if called_parse_args:
+        m5.fatal("Can't add an option after calling SimpleOpts.parse_args")
+
+    parser.add_option(*args, **kwargs)
+
+def parse_args():
+    global called_parse_args
+    called_parse_args = True
+
+    return parser.parse_args()
+
+def set_usage(*args, **kwargs):
+    parser.set_usage(*args, **kwargs)
+
+def print_help(*args, **kwargs):
+    parser.print_help(*args, **kwargs)
+