##// END OF EJS Templates
sha1dc: import latest version from github...
sha1dc: import latest version from github After the recent SHA1 news, the attacks are serious enough we should be more proactive. This code will at least allow detection of attacks early. It's already widely deployed in Git. This is git revision 855827c583bc30645ba427885caa40c5b81764d2 of the sha1collisiondetection repo[0], with most of the files omitted. A follow-up change will introduce Python bindings for this code. 0: https://github.com/cr-marcstevens/sha1collisiondetection Differential Revision: https://phab.mercurial-scm.org/D7814

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filepatterns.rs
380 lines | 11.6 KiB | application/rls-services+xml | RustLexer
// filepatterns.rs
//
// Copyright 2019 Raphaël Gomès <rgomes@octobus.net>
//
// This software may be used and distributed according to the terms of the
// GNU General Public License version 2 or any later version.
//! Handling of Mercurial-specific patterns.
use crate::{
utils::SliceExt, FastHashMap, LineNumber, PatternError, PatternFileError,
};
use lazy_static::lazy_static;
use regex::bytes::{NoExpand, Regex};
use std::fs::File;
use std::io::Read;
use std::path::{Path, PathBuf};
use std::vec::Vec;
lazy_static! {
static ref RE_ESCAPE: Vec<Vec<u8>> = {
let mut v: Vec<Vec<u8>> = (0..=255).map(|byte| vec![byte]).collect();
let to_escape = b"()[]{}?*+-|^$\\.&~# \t\n\r\x0b\x0c";
for byte in to_escape {
v[*byte as usize].insert(0, b'\\');
}
v
};
}
/// These are matched in order
const GLOB_REPLACEMENTS: &[(&[u8], &[u8])] =
&[(b"*/", b"(?:.*/)?"), (b"*", b".*"), (b"", b"[^/]*")];
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
pub enum PatternSyntax {
Regexp,
/// Glob that matches at the front of the path
RootGlob,
/// Glob that matches at any suffix of the path (still anchored at
/// slashes)
Glob,
Path,
RelPath,
RelGlob,
RelRegexp,
RootFiles,
}
/// Transforms a glob pattern into a regex
fn glob_to_re(pat: &[u8]) -> Vec<u8> {
let mut input = pat;
let mut res: Vec<u8> = vec![];
let mut group_depth = 0;
while let Some((c, rest)) = input.split_first() {
input = rest;
match c {
b'*' => {
for (source, repl) in GLOB_REPLACEMENTS {
if let Some(rest) = input.drop_prefix(source) {
input = rest;
res.extend(*repl);
break;
}
}
}
b'?' => res.extend(b"."),
b'[' => {
match input.iter().skip(1).position(|b| *b == b']') {
None => res.extend(b"\\["),
Some(end) => {
// Account for the one we skipped
let end = end + 1;
res.extend(b"[");
for (i, b) in input[..end].iter().enumerate() {
if *b == b'!' && i == 0 {
res.extend(b"^")
} else if *b == b'^' && i == 0 {
res.extend(b"\\^")
} else if *b == b'\\' {
res.extend(b"\\\\")
} else {
res.push(*b)
}
}
res.extend(b"]");
input = &input[end + 1..];
}
}
}
b'{' => {
group_depth += 1;
res.extend(b"(?:")
}
b'}' if group_depth > 0 => {
group_depth -= 1;
res.extend(b")");
}
b',' if group_depth > 0 => res.extend(b"|"),
b'\\' => {
let c = {
if let Some((c, rest)) = input.split_first() {
input = rest;
c
} else {
c
}
};
res.extend(&RE_ESCAPE[*c as usize])
}
_ => res.extend(&RE_ESCAPE[*c as usize]),
}
}
res
}
fn escape_pattern(pattern: &[u8]) -> Vec<u8> {
pattern
.iter()
.flat_map(|c| RE_ESCAPE[*c as usize].clone())
.collect()
}
fn parse_pattern_syntax(kind: &[u8]) -> Result<PatternSyntax, PatternError> {
match kind {
b"re" => Ok(PatternSyntax::Regexp),
b"path" => Ok(PatternSyntax::Path),
b"relpath" => Ok(PatternSyntax::RelPath),
b"rootfilesin" => Ok(PatternSyntax::RootFiles),
b"relglob" => Ok(PatternSyntax::RelGlob),
b"relre" => Ok(PatternSyntax::RelRegexp),
b"glob" => Ok(PatternSyntax::Glob),
b"rootglob" => Ok(PatternSyntax::RootGlob),
_ => Err(PatternError::UnsupportedSyntax(
String::from_utf8_lossy(kind).to_string(),
)),
}
}
/// Builds the regex that corresponds to the given pattern.
/// If within a `syntax: regexp` context, returns the pattern,
/// otherwise, returns the corresponding regex.
fn _build_single_regex(
syntax: PatternSyntax,
pattern: &[u8],
globsuffix: &[u8],
) -> Vec<u8> {
if pattern.is_empty() {
return vec![];
}
match syntax {
PatternSyntax::Regexp => pattern.to_owned(),
PatternSyntax::RelRegexp => {
if pattern[0] == b'^' {
return pattern.to_owned();
}
[b".*", pattern].concat()
}
PatternSyntax::Path | PatternSyntax::RelPath => {
if pattern == b"." {
return vec![];
}
[escape_pattern(pattern).as_slice(), b"(?:/|$)"].concat()
}
PatternSyntax::RootFiles => {
let mut res = if pattern == b"." {
vec![]
} else {
// Pattern is a directory name.
[escape_pattern(pattern).as_slice(), b"/"].concat()
};
// Anything after the pattern must be a non-directory.
res.extend(b"[^/]+$");
res
}
PatternSyntax::RelGlob => {
let glob_re = glob_to_re(pattern);
if let Some(rest) = glob_re.drop_prefix(b"[^/]*") {
[b".*", rest, globsuffix].concat()
} else {
[b"(?:|.*/)", glob_re.as_slice(), globsuffix].concat()
}
}
PatternSyntax::Glob | PatternSyntax::RootGlob => {
[glob_to_re(pattern).as_slice(), globsuffix].concat()
}
}
}
const GLOB_SPECIAL_CHARACTERS: [u8; 7] =
[b'*', b'?', b'[', b']', b'{', b'}', b'\\'];
/// Wrapper function to `_build_single_regex` that short-circuits 'exact' globs
/// that don't need to be transformed into a regex.
pub fn build_single_regex(
kind: &[u8],
pat: &[u8],
globsuffix: &[u8],
) -> Result<Vec<u8>, PatternError> {
let enum_kind = parse_pattern_syntax(kind)?;
if enum_kind == PatternSyntax::RootGlob
&& !pat.iter().any(|b| GLOB_SPECIAL_CHARACTERS.contains(b))
{
let mut escaped = escape_pattern(pat);
escaped.extend(b"(?:/|$)");
Ok(escaped)
} else {
Ok(_build_single_regex(enum_kind, pat, globsuffix))
}
}
lazy_static! {
static ref SYNTAXES: FastHashMap<&'static [u8], &'static [u8]> = {
let mut m = FastHashMap::default();
m.insert(b"re".as_ref(), b"relre:".as_ref());
m.insert(b"regexp".as_ref(), b"relre:".as_ref());
m.insert(b"glob".as_ref(), b"relglob:".as_ref());
m.insert(b"rootglob".as_ref(), b"rootglob:".as_ref());
m.insert(b"include".as_ref(), b"include".as_ref());
m.insert(b"subinclude".as_ref(), b"subinclude".as_ref());
m
};
}
pub type PatternTuple = (Vec<u8>, LineNumber, Vec<u8>);
type WarningTuple = (PathBuf, Vec<u8>);
pub fn parse_pattern_file_contents<P: AsRef<Path>>(
lines: &[u8],
file_path: P,
warn: bool,
) -> (Vec<PatternTuple>, Vec<WarningTuple>) {
let comment_regex = Regex::new(r"((?:^|[^\\])(?:\\\\)*)#.*").unwrap();
let comment_escape_regex = Regex::new(r"\\#").unwrap();
let mut inputs: Vec<PatternTuple> = vec![];
let mut warnings: Vec<WarningTuple> = vec![];
let mut current_syntax = b"relre:".as_ref();
for (line_number, mut line) in lines.split(|c| *c == b'\n').enumerate() {
let line_number = line_number + 1;
let line_buf;
if line.contains(&b'#') {
if let Some(cap) = comment_regex.captures(line) {
line = &line[..cap.get(1).unwrap().end()]
}
line_buf = comment_escape_regex.replace_all(line, NoExpand(b"#"));
line = &line_buf;
}
let mut line = line.trim_end();
if line.is_empty() {
continue;
}
if let Some(syntax) = line.drop_prefix(b"syntax:") {
let syntax = syntax.trim();
if let Some(rel_syntax) = SYNTAXES.get(syntax) {
current_syntax = rel_syntax;
} else if warn {
warnings
.push((file_path.as_ref().to_owned(), syntax.to_owned()));
}
continue;
}
let mut line_syntax: &[u8] = &current_syntax;
for (s, rels) in SYNTAXES.iter() {
if let Some(rest) = line.drop_prefix(rels) {
line_syntax = rels;
line = rest;
break;
}
if let Some(rest) = line.drop_prefix(&[s, &b":"[..]].concat()) {
line_syntax = rels;
line = rest;
break;
}
}
inputs.push((
[line_syntax, line].concat(),
line_number,
line.to_owned(),
));
}
(inputs, warnings)
}
pub fn read_pattern_file<P: AsRef<Path>>(
file_path: P,
warn: bool,
) -> Result<(Vec<PatternTuple>, Vec<WarningTuple>), PatternFileError> {
let mut f = File::open(file_path.as_ref())?;
let mut contents = Vec::new();
f.read_to_end(&mut contents)?;
Ok(parse_pattern_file_contents(&contents, file_path, warn))
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn escape_pattern_test() {
let untouched = br#"!"%',/0123456789:;<=>@ABCDEFGHIJKLMNOPQRSTUVWXYZ_`abcdefghijklmnopqrstuvwxyz"#;
assert_eq!(escape_pattern(untouched), untouched.to_vec());
// All escape codes
assert_eq!(
escape_pattern(br#"()[]{}?*+-|^$\\.&~# \t\n\r\v\f"#),
br#"\(\)\[\]\{\}\?\*\+\-\|\^\$\\\\\.\&\~\#\ \\t\\n\\r\\v\\f"#
.to_vec()
);
}
#[test]
fn glob_test() {
assert_eq!(glob_to_re(br#"?"#), br#"."#);
assert_eq!(glob_to_re(br#"*"#), br#"[^/]*"#);
assert_eq!(glob_to_re(br#"**"#), br#".*"#);
assert_eq!(glob_to_re(br#"**/a"#), br#"(?:.*/)?a"#);
assert_eq!(glob_to_re(br#"a/**/b"#), br#"a/(?:.*/)?b"#);
assert_eq!(glob_to_re(br#"[a*?!^][^b][!c]"#), br#"[a*?!^][\^b][^c]"#);
assert_eq!(glob_to_re(br#"{a,b}"#), br#"(?:a|b)"#);
assert_eq!(glob_to_re(br#".\*\?"#), br#"\.\*\?"#);
}
#[test]
fn test_parse_pattern_file_contents() {
let lines = b"syntax: glob\n*.elc";
assert_eq!(
vec![(b"relglob:*.elc".to_vec(), 2, b"*.elc".to_vec())],
parse_pattern_file_contents(lines, Path::new("file_path"), false)
.0,
);
let lines = b"syntax: include\nsyntax: glob";
assert_eq!(
parse_pattern_file_contents(lines, Path::new("file_path"), false)
.0,
vec![]
);
let lines = b"glob:**.o";
assert_eq!(
parse_pattern_file_contents(lines, Path::new("file_path"), false)
.0,
vec![(b"relglob:**.o".to_vec(), 1, b"**.o".to_vec())]
);
}
#[test]
fn test_build_single_regex_shortcut() {
assert_eq!(
br"(?:/|$)".to_vec(),
build_single_regex(b"rootglob", b"", b"").unwrap()
);
assert_eq!(
br"whatever(?:/|$)".to_vec(),
build_single_regex(b"rootglob", b"whatever", b"").unwrap()
);
assert_eq!(
br"[^/]*\.o".to_vec(),
build_single_regex(b"rootglob", b"*.o", b"").unwrap()
);
}
}