PHP glob-style matching - php

Question

To keep things short, I wrote an access-control system.
One of the requirements of this system is to check whether a canonical/normalized path can be accessed or not by matching it against a pattern.
First thoughts would fall on PREG, problem is, the patterns are file-based, ie, similar to those accepted by glob(). Basically, it's just patterns containing ? (match one arbitrary character) or * (match any character).
So in simple terms, I need to recreate glob()'s matching functionality on PHP.
Sample code:
function path_matches($path, $pattern){
// ... ?
}
path_matches('path/index.php', 'path/*'); // true
path_matches('path2/', 'path/*'); // false
path_matches('path2/test.php', 'path2/*.php'); // true
A possible solution would be to convert $pattern into a regular expression than use preg_match(), is there any other way though?
NB: The reason why I can't use regex is that patterns will be written by non-programmers.

Answer 1

Use fnmatch(), which seems to do the trick.

Answer 2

Converting to a regex seems like the best solution to me. All you need to do is convert * to .*, ? to . and preg_quote. However it's not as simple as it may seem because it's a bit of a chicken-and-egg problem in terms of the order in which you do things.
I don't like this solution but it's the best I can come up with: use a regex to generate the regex.
function path_matches($path, $pattern, $ignoreCase = FALSE) {
$expr = preg_replace_callback('/[\\\\^$.[\\]|()?*+{}\\-\\/]/', function($matches) {
switch ($matches[0]) {
case '*':
return '.*';
case '?':
return '.';
default:
return '\\'.$matches[0];
}
}, $pattern);
$expr = '/'.$expr.'/';
if ($ignoreCase) {
$expr .= 'i';
}
return (bool) preg_match($expr, $path);
}
EDIT Added case-sensitivity option.
See it working

Answer 3

There is already a function in PHP, included since PHP 4.3.0.
fnmatch() checks if the passed string would match the given shell wildcard pattern.

Answer 4

From the PHP documentation for glob(). I think preg_match is the best solution anyway.
http://php.net/manual/en/function.glob.php
<?php
function match_wildcard( $wildcard_pattern, $haystack ) {
$regex = str_replace(
array("\*", "\?"), // wildcard chars
array('.*','.'), // regexp chars
preg_quote($wildcard_pattern)
);
return preg_match('/^'.$regex.'$/is', $haystack);
}
$test = "foobar and blob\netc.";
var_dump(
match_wildcard('foo*', $test), // TRUE
match_wildcard('bar*', $test), // FALSE
match_wildcard('*bar*', $test), // TRUE
match_wildcard('**blob**', $test), // TRUE
match_wildcard('*a?d*', $test), // TRUE
match_wildcard('*etc**', $test) // TRUE
);
?>

Answer 5

I think this should work for turning glob-patterns into regex-patterns:
function glob2regex($globPatt) {
return '/'.preg_replace_callback('/./u', function($m) {
switch($m[0]) {
case '*': return '.*';
case '?': return '.';
}
return preg_quote($m[0],'/');
}, $globPatt).'\z/AsS';
}
You might want to use [^\\/]* for * instead if you want to prevent * from matching over directory names.