✨feature: Initial MVP

src/Support/FileLock.php

@@ -0,0 +1,45 @@
+<?php
+// phpcs:disable PEAR.Commenting.FileComment,PEAR.Commenting.ClassComment
+
+/**
+ * File locking support.
+ */
+
+declare(strict_types=1);
+
+namespace IronKanban\Support;
+
+/**
+ * Runs callbacks while holding an exclusive file lock.
+ */
+final class FileLock
+{
+    /**
+     * Execute a callback under an exclusive lock.
+     *
+     * @param string   $path     Lock file path.
+     * @param callable $callback Callback to execute.
+     *
+     * @return mixed
+     */
+    public static function run(string $path, callable $callback): mixed
+    {
+        ensure_directory(dirname($path));
+        $handle = fopen($path, 'c+');
+
+        if ($handle === false) {
+            throw new \RuntimeException('Unable to open lock file: ' . $path);
+        }
+
+        try {
+            if (!flock($handle, LOCK_EX)) {
+                throw new \RuntimeException('Unable to lock file: ' . $path);
+            }
+
+            return $callback();
+        } finally {
+            flock($handle, LOCK_UN);
+            fclose($handle);
+        }
+    }
+}