Added argv_translator.py

Signed-off-by: Daniel Walton <dwalton@cumulusnetworks.com>
To use this run:
../tools/argv_translator.py bgp_route.c

It will update the argv[] instances with the corrent index and adds
'->arg'

diff --git a/tools/argv_translator.py b/tools/argv_translator.py
new file mode 100755 (executable)
index 0000000..791ae54
--- /dev/null
+++ b/tools/argv_translator.py
@@ -0,0 +1,142 @@
+#!/usr/bin/env python
+
+import re
+import sys
+import os
+from pprint import pformat
+
+
+def token_is_variable(token):
+
+    if token.isdigit():
+        return True
+
+    if token.startswith('('):
+        assert token.endswith(')'), "token %s should end with )" % token
+        return True
+
+    if token.startswith('['):
+        assert token.endswith(']'), "token %s should end with ]" % token
+        return True
+
+    if token.startswith('{'):
+        # I don't really care about checking for this I just put
+        # these asserts in here to bug sharpd
+        assert token.endswith('}'), "token %s should end with }" % token
+        return True
+
+    assert '|' not in token, "Weird token %s has a | but does not start with [ or (" % token
+
+    if token in ('WORD',
+                 '.LINE', # where is this defined?
+                 'A.B.C.D',
+                 'A.B.C.D/M',
+                 'X:X::X:X',
+                 'X:X::X:X/M',
+                 'ASN:nn_or_IP-address:nn'): # where is this defined?
+        return True
+
+    re_number_range = re.search('^<\d+-\d+>$', token)
+    if re_number_range:
+        return True
+
+    return False
+
+
+def get_argv_translator(line):
+    table = {}
+    line = line.strip()
+    assert line.startswith('"'), "line does not start with \"\n%s" % line
+    assert line.endswith('",'), "line does not end with \",\n%s" % line
+
+    line = line[1:-2]
+
+    funky_chars = ('+', '"')
+    for char in funky_chars:
+        if char in line:
+            raise Exception("Add support for tokens in\n%s\n\nsee BGP_INSTANCE_CMD down below" % line)
+
+    old_style_index = 0
+    for (token_index, token) in enumerate(line.split()):
+        if token_is_variable(token):
+            # print "%s is a token" % token
+            table[old_style_index] = token_index
+            old_style_index += 1
+        else:
+            # print "%s is NOT a token" % token
+            pass
+
+    return table
+
+
+def update_argvs(filename):
+    lines = []
+
+    with open(filename,  'r') as fh:
+        state = None
+        defun_line_number = None
+        cmd_string = None
+        argv_translator = {}
+        print_translator = False
+
+        for (line_number, line) in enumerate(fh.readlines()):
+            new_line = line
+
+            if state is None:
+                if line.startswith('DEFUN ('):
+                    state = 'DEFUN_HEADER'
+                    defun_line_number = line_number
+
+            elif state == 'DEFUN_HEADER':
+                if line.startswith('DEFUN'):
+                    raise Exception("ERROR on line %d, found DEFUN inside DEFUN" % line_number)
+
+                elif line.startswith('ALIAS'):
+                    raise Exception("ERROR on line %d, found ALIAS inside DEFUN" % line_number)
+
+                elif line.strip() == '{':
+                    state = 'DEFUN_BODY'
+
+                elif line_number == defun_line_number + 2:
+
+                    # bgpd/bgp_vty.h
+                    line = line.replace('" CMD_AS_RANGE "', '<1-4294967295>')
+                    line = line.replace('" DYNAMIC_NEIGHBOR_LIMIT_RANGE "', '<1-5000>')
+                    line = line.replace('" BGP_INSTANCE_CMD "', '(view|vrf) WORD')
+                    line = line.replace('" BGP_INSTANCE_ALL_CMD "', '(view|vrf) all')
+                    argv_translator = get_argv_translator(line)
+                    print_translator = True
+
+            elif state == 'DEFUN_BODY':
+                if line.rstrip() == '}':
+                    state = None
+                    defun_line_number = None
+                    cmd_string = None
+                    argv_translator = {}
+
+                elif 'argv[' in new_line:
+                    for index in reversed(argv_translator.keys()):
+                        old_argv = "argv[%d]" % index
+                        new_argv = "argv[%d]->arg" % argv_translator[index]
+                        new_line = new_line.replace(old_argv, new_argv)
+
+            # uncomment to debug state machine
+            print "%5d %12s: %s" % (line_number, state, new_line.rstrip())
+            if print_translator:
+                print "%s\n" % pformat(argv_translator)
+                print_translator = False
+
+            lines.append(new_line)
+
+    with open(filename, 'w') as fh:
+        for line in lines:
+            fh.write(line)
+
+
+if __name__ == '__main__':
+
+    filename = sys.argv[1]
+    if os.path.exists(filename):
+        update_argvs(filename)
+    else:
+        print "ERROR: could not find file %s" % filename