Merge pull request #55 from codalogic/ruby-abnf-extracter

Ruby ABNF extracter

abnf/make-abnf.rb

@@ -0,0 +1,157 @@
+# Copyright (C) 2014,2015 American Registry for Internet Numbers (ARIN)
+#
+# Permission to use, copy, modify, and/or distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
+# IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+# Configuration
+$parslet_src_file = "../lib/jcr/parser.rb"
+$abnf_out_file = "jcr-abnf.txt"
+$margin = 0
+$indent = 19
+$keyword_indent = 30
+
+# Primary data stores
+$mappings = {}
+$lines = []
+$keywords = {}
+
+def main
+    read_parslet_def
+    write_abnf
+end
+
+def read_parslet_def
+    File.foreach( $parslet_src_file ) { |line|
+        conditionally_grab_mapping( line )
+        conditionally_grab_abnf( line )
+        conditionally_grab_keywords( line )
+    }
+end
+
+def conditionally_grab_mapping( line )
+    # Example haystack:  #/ spcCmnt -> sp-cmt
+    if m = %r|^\s*#/\s*([\w?]+)\s*->\s*(.*)|.match( line )
+        key, value = m.captures
+        $mappings[key] = value
+    end
+end
+
+def conditionally_grab_abnf( line )
+    # Example haystack:  #! spcCmnt = spaces / comment
+    if m = /^\s*#!\s*(.*)/.match( line )
+        $lines << m[1]
+    end
+end
+
+def conditionally_grab_keywords( line )
+    # Example haystack:  #> jcr-version-kw = "jcr-version"
+    if m = /^\s*#>\s*([\w_\-]+kw)(\s*=\s*)"([^"]+)"/.match( line )
+        name, equals, keyword = m.captures
+        ascii_codes = keyword.chars.map{ |c| "%02X" % c.ord }.join( '.' )
+        comment_padding = ' ' * [($keyword_indent - 3*keyword.length), 0].max
+        line = name + equals + '%x' + ascii_codes + comment_padding + ' ; "' + keyword + '"'
+        $keywords[name] = line
+    end
+end
+
+def write_abnf
+    File.open( $abnf_out_file, 'w' ) { |fout|
+        print_captured_abnf( fout )
+        print_keywords( fout )
+        print_referenced_rfc5234_rules( fout )
+    }
+end
+
+def print_captured_abnf( fout )
+    for line in $lines
+        line = do_name_mappings( line )
+        pretty_print( line, fout )
+    end
+end
+
+def do_name_mappings( line )
+    for mapping_from in mapping_keys_sorted_longest_first
+        line.gsub!( mapping_from, $mappings[mapping_from] )
+    end
+    line.gsub!( '_', '-' )
+    return line
+end
+
+def mapping_keys_sorted_longest_first
+    return $mappings.keys.sort_by { |m| m.length }.reverse
+end
+
+def print_keywords( fout )
+    pretty_print( '', fout )
+    pretty_print( ';; Keywords', fout )
+    for kw in $keywords.keys().sort
+        pretty_print( $keywords[kw], fout )
+    end
+end
+
+def print_referenced_rfc5234_rules( fout )
+    rfc5234_core_rules = [
+        'ALPHA          =  %x41-5A / %x61-7A   ; A-Z / a-z',
+        'CR             =  %x0D         ; carriage return',
+        'DIGIT          =  %x30-39      ; 0-9',
+        # 'DQUOTE         =  %x22         ; " (Double Quote)',
+        'HEXDIG         =  DIGIT / "A" / "B" / "C" / "D" / "E" / "F"',
+        'HTAB           =  %x09         ; horizontal tab',
+        'LF             =  %x0A         ; linefeed',
+        'SP             =  %x20         ; space',
+        'WSP            =  SP / HTAB    ; white space'
+        ]
+    pretty_print( '', fout )
+    pretty_print( ';; Referenced RFC 5234 Core Rules', fout )
+    for rule in rfc5234_core_rules
+        pretty_print( rule, fout )
+    end
+end
+
+def pretty_print( line, fout )
+    if is_blank_line?( line )
+        fout.write( "\n" )
+    else
+        fout.write( ' ' * $margin )
+        if is_block_comment?( line )
+            fout.write( line + "\n" )
+        elsif comment = local_comment( line )
+            fout.write( ' ' * $indent + comment + "\n" )
+        elsif mapping = abnf_mapping( line )
+            name, expansion = mapping
+            equals = ' = '
+            padding_needed = [ $indent - (name.length + equals.length), 0 ].max
+            padding = ' ' * padding_needed
+            fout.write( name + padding + equals + expansion + "\n" )
+        else
+            fout.write( ' ' * $indent + line + "\n" ) # A 2nd/3rd expression line
+        end
+    end
+end
+
+def is_blank_line?( line )
+    return /^\s*$/.match( line )
+end
+
+def is_block_comment?( line )
+    return /^\s*;;/.match( line )
+end
+
+def local_comment( line )
+    return (m = /^\s*(;.*)/.match( line )) ? m[1] : false
+end
+
+def abnf_mapping( line )
+    return (m = /([\w_\-]+)\s*=\s*(.*)/.match( line )) ? [m[1], m[2]] : false
+end
+
+main