Add script that produces a human-readable grammar from Bison output

(cherry picked from commit 2ee2fc4934052a0a5811ecd46438fbaaea2c5e7a)

diff --git a/scripts/auxiliar/yyout2grammar.py b/scripts/auxiliar/yyout2grammar.py
new file mode 100755 (executable)
index 0000000..25b6f25
--- /dev/null
+++ b/scripts/auxiliar/yyout2grammar.py
@@ -0,0 +1,104 @@
+#! /usr/bin/env python
+
+#  Convert from bison output file parser.output to
+#  Grammar and index.
+#  Drops all of the state information.
+#  Converts \\ to \
+#  Eliminates the @ variables created when {} is placed in the middle of a rule##  all of the c-code stuff
+#
+#
+#  Copyright 2005 by Carl D. Sorensen
+#
+
+# to create input file, run
+#   bison -v parser.yy
+# this will create a file parser.output
+# then run
+#   yyout2grammar.py parser.output your_output_file
+#
+
+import sys
+import re
+
+atre = re.compile('(@\d+):')
+
+write_me = True
+
+if len(sys.argv)!=3:
+    print "Usage: yyout2grammar.py parser_output_file grammar_file."
+else:
+    in_name = sys.argv[1] 
+    out_name = sys.argv[2]
+
+    print "input file name",in_name
+    print "output file name",out_name
+    in_file = open(in_name,'r')
+    out_file= open(out_name, 'w')
+
+    at_items=[]
+    inline = in_file.readline()
+    while inline != '' and not(inline.startswith("Grammar")):
+        inline = in_file.readline()
+    if inline != '':
+        out_file.write(inline)
+        inline = in_file.readline()
+        while inline != '' and not(inline.startswith("Terminals")):
+            i = inline.find("$accept:")
+            if i>-1:
+                write_me = False
+                inline = in_file.readline()
+            atfound = re.findall(atre,inline)
+            if len(atfound) > 0:
+                at_items.extend(atfound)
+                print at_items
+                write_me = False
+                inline=in_file.readline()
+            else:
+                for at_item in at_items:
+                    i=inline.find(at_item)
+                    if i >= 0:
+                        inline=inline[:i] + inline[i+len(at_item):]
+                    i=inline.find('"\\\\')
+                    while i > -1 :
+                        inline = inline[:i+1]+inline[i+2:]
+                        i = inline.find('"\\\\')
+            if write_me:
+                out_file.write(inline)
+            inline = in_file.readline()
+            write_me = True
+    index_items = []
+    #  Write the Terminals header line and the following blank line
+    out_file.write(inline)
+    inline = in_file.readline()
+    out_file.write(inline)
+    inline = in_file.readline()
+    while inline != '' and not(inline.startswith("Nonterminals")):
+        i=inline.find('"\\\\')
+        while i > -1 :
+            inline = inline[:i+1]+inline[i+2:]
+            i = inline.find('"\\\\')
+        index_items.append(inline)
+        inline = in_file.readline()
+    index_items.sort(lambda x,y:cmp(x.lower(),y.lower()))
+    for index_item in index_items:
+        out_file.write(index_item)
+    out_file.write('\n')
+    # Write the Nonterminals header and the blank line
+    out_file.write(inline)
+    inline = in_file.readline()
+    out_file.write(inline)
+    index_items = []
+    index_item=in_file.readline()
+    inline=in_file.readline()
+    while inline != '' and not(inline.startswith("state")):
+        while inline.startswith("    "):
+            index_item = index_item + inline
+            inline = in_file.readline()
+        if not(index_item.startswith("@")) and \
+               not(index_item.startswith("$accept")):
+            index_items.append(index_item)
+        index_item = inline
+        inline=in_file.readline()
+    index_items.sort(lambda x,y:cmp(x.lower(),y.lower()))
+    for index_item in index_items:
+        out_file.write(index_item)