adds network config file parser to shared modules

This commit adds a new shared module that parses network device configuration
files.  It is used to build modules that work with the various supported
network device operating systems

lib/ansible/module_utils/netcfg.py

@@ -0,0 +1,85 @@
+#
+# (c) 2015 Peter Sprygada, <psprygada@ansible.com>
+#
+# This file is part of Ansible
+#
+# Ansible is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# Ansible is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+import re
+import collections
+
+class ConfigLine(object):
+
+    def __init__(self, text):
+        self.text = text
+        self.children = list()
+        self.parents = list()
+        self.raw = None
+
+    def __str__(self):
+        return self.raw
+
+    def __eq__(self, other):
+        if self.text == other.text:
+            return self.parents == other.parents
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
+def parse(lines, indent):
+        toplevel = re.compile(r'\S')
+        childline = re.compile(r'^\s*(.+)$')
+        repl = r'([{|}|;])'
+
+        ancestors = list()
+        config = list()
+
+        for line in str(lines).split('\n'):
+            text = str(re.sub(repl, '', line)).strip()
+
+            cfg = ConfigLine(text)
+            cfg.raw = line
+
+            if not text or text[0] in ['!', '#']:
+                continue
+
+            # handle top level commands
+            if toplevel.match(line):
+                ancestors = [cfg]
+
+            # handle sub level commands
+            else:
+                match = childline.match(line)
+                line_indent = match.start(1)
+                level = int(line_indent / indent)
+                parent_level = level - 1
+
+                cfg.parents = ancestors[:level]
+
+                if level > len(ancestors):
+                    config.append(cfg)
+                    continue
+
+                for i in range(level, len(ancestors)):
+                    ancestors.pop()
+
+                ancestors.append(cfg)
+                ancestors[parent_level].children.append(cfg)
+
+            config.append(cfg)
+
+        return config
+
+