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| 1 | +extern crate regex; |
| 2 | + |
| 3 | +use regex::Regex; |
| 4 | + |
| 5 | +use std::env; |
| 6 | +use std::fs::File; |
| 7 | +use std::io::prelude::*; |
| 8 | +use std::io::{BufReader, BufWriter}; |
| 9 | +use std::path::Path; |
| 10 | + |
| 11 | +// Generate character mapping tables directly from the specification. |
| 12 | +fn main() { |
| 13 | + // Input from the RFC. |
| 14 | + let in_file = File::open("rfc3454.txt").unwrap(); |
| 15 | + let mut reader = BufReader::new(in_file); |
| 16 | + |
| 17 | + // Output to a Rust source file. |
| 18 | + let out_dir = env::var("OUT_DIR").unwrap(); |
| 19 | + let dest_path = Path::new(&out_dir).join("rfc3454.rs"); |
| 20 | + let out_file = File::create(&dest_path).unwrap(); |
| 21 | + let mut writer = BufWriter::new(out_file); |
| 22 | + |
| 23 | + // Generate tables. |
| 24 | + include_table(&mut writer, &mut reader, "A.1"); |
| 25 | + include_table(&mut writer, &mut reader, "B.2"); |
| 26 | +} |
| 27 | + |
| 28 | +// Generate code for the named mapping table. |
| 29 | +fn include_table<R: Read, W: Write>(writer: &mut BufWriter<W>, reader: &mut BufReader<R>, tablename: &str) { |
| 30 | + // Scan to start of table. |
| 31 | + loop { |
| 32 | + let mut line = String::new(); |
| 33 | + reader.read_line(&mut line).unwrap(); |
| 34 | + if line.contains("Start Table") && line.contains(tablename) { |
| 35 | + break; |
| 36 | + } |
| 37 | + } |
| 38 | + |
| 39 | + // Output table declaration. |
| 40 | + write!(writer, "pub const RFC3454_{}: &[(char, Option<char>, Option<&str>)] = &[\n", tablename.replace(".", "_")).unwrap(); |
| 41 | + |
| 42 | + // For each line: |
| 43 | + let target_re = Regex::new(r"([0-9A-F]+)(-([0-9A-F]+))?(; ([0-9A-F]+)( ([0-9A-F]+))?( ([0-9A-F]+))?( ([0-9A-F]+))?;)?").unwrap(); |
| 44 | + loop { |
| 45 | + let mut line = String::new(); |
| 46 | + reader.read_line(&mut line).unwrap(); |
| 47 | + |
| 48 | + // Done when reach the end of the table. |
| 49 | + if line.contains("End Table") { |
| 50 | + break; |
| 51 | + } |
| 52 | + |
| 53 | + // Skip RFC metadata. |
| 54 | + if line.contains("Hoffman & Blanchet") || line.contains("RFC 3454") { |
| 55 | + continue; |
| 56 | + } |
| 57 | + |
| 58 | + // Generate an entry for each data line. |
| 59 | + if let Some(captures) = target_re.captures(&line) { |
| 60 | + let start = captures.get(1).unwrap(); |
| 61 | + |
| 62 | + // '\u{start}', |
| 63 | + let mut entry = String::from("'\\u{"); |
| 64 | + entry.push_str(start.as_str()); |
| 65 | + entry.push_str("}', "); |
| 66 | + |
| 67 | + // '\u{start}', None, |
| 68 | + // '\u{start}', Some('\u{end}'), |
| 69 | + match captures.get(3) { |
| 70 | + None => entry.push_str("None, "), |
| 71 | + Some(end) => { |
| 72 | + entry.push_str("Some('\\u{"); |
| 73 | + entry.push_str(end.as_str()); |
| 74 | + entry.push_str("}'), "); |
| 75 | + } |
| 76 | + } |
| 77 | + |
| 78 | + // 0-4 character replacement string |
| 79 | + let mut replace = String::new(); |
| 80 | + for &i in [5, 7, 9, 11].iter() { |
| 81 | + match captures.get(i) { |
| 82 | + None => break, |
| 83 | + Some(c) => { |
| 84 | + replace.push_str("\\u{"); |
| 85 | + replace.push_str(c.as_str()); |
| 86 | + replace.push_str("}"); |
| 87 | + } |
| 88 | + } |
| 89 | + } |
| 90 | + |
| 91 | + // '\u{start}', None, None |
| 92 | + // '\u{start}', None, Some("replace") |
| 93 | + if replace.is_empty() { |
| 94 | + entry.push_str("None"); |
| 95 | + } else { |
| 96 | + entry.push_str("Some(\""); |
| 97 | + entry.push_str(&replace); |
| 98 | + entry.push_str("\")"); |
| 99 | + } |
| 100 | + |
| 101 | + // Output entry for this line. |
| 102 | + write!(writer, " ({}),\n", entry).unwrap(); |
| 103 | + } |
| 104 | + } |
| 105 | + |
| 106 | + // End table definition. |
| 107 | + write!(writer, "];\n\n").unwrap(); |
| 108 | +} |
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