Detect broken symlink in PHP on Windows 7 + Apache environment - php

Question

I have a Windows 7 dev environment and I am using symlinks (not junctions) with php's symlink() function. Everything works fine until a target of a symlink gets deleted. When that happens all the PHP's file functions (file_exists(), is_file(), is_dir(), is_link(),...) return false although the symlink is still there.
This gets even more troubling if the broken symlink was originally targetting a directory. I can do file_put_contents() on the symlink path, which creates a file on the original target directory path. That's quite unfortunate and unpredictable.
So to my question: is there a way to detect a broken symlink in PHP on Windows 7 environment? I need whatever decent solution possible (an exec() or something like that). The production server is running standard LAMP configuration which works fine as expected.
I am using XAMPP with PHP 5.5.3.
A sample script:
$dir_path = __DIR__ . '/temporary_directory';
$link_path = __DIR__ . '/broken_symlink';
mkdir($dir_path);
symlink($dir_path, $link_path);
rmdir($dir_path);
echo 'file_exists(): ';
var_dump(file_exists($link_path));// false
echo "<br>\n";
echo 'is_file(): ';
var_dump(is_file($link_path));// false
echo "<br>\n";
echo 'is_dir(): ';
var_dump(is_dir($link_path));// false
echo "<br>\n";
echo 'is_link(): ';
var_dump(is_link($link_path));// false
echo "<br>\n";
echo 'readlink(): ';
var_dump(readlink($link_path));// false
echo "<br>\n";
// Now it is possible to create file:
file_put_contents($link_path, '');
// which creates a new file on the $dir_path. That makes the symlink somewhat hybrid as Windows Explorer thinks it is a directory symlink but it points to a file (so it's unable to resolve it).

Answer 1

I have come up with a solution. I am not completely happy about it but it should work.
function is_link_on_windows($path) {
$parent_dir_path = dirname($path);
if (false === file_exists($parent_dir_path)) return false;
$filename_regex = preg_quote(substr($path, strlen($parent_dir_path) + 1), '#');
// DOS' dir command is unlike PHP sensitive about the path format.
$parent_dir_path = realpath($parent_dir_path);
exec('dir ' . $parent_dir_path, $dir_output);
foreach ($dir_output as $line) {
// Symlink's entry should look like this:
// broken_symlink [C:\xampp\htdocs\symlink_test\temporary_directory]
// where the part within square brackets is the symlink's target.
if (preg_match('#\\s' . $filename_regex . '\\s\\[[^\\]]+\\]#', $line)) {
return true;
}
}
return false;
}