Initial commit

src/Key/FileKey.php

@@ -0,0 +1,84 @@
+<?php
+
+namespace NoccyLabs\Ipc\Key;
+
+class FileKey implements KeyInterface
+{
+    private $proj;
+
+    private $pathname;
+
+    /**
+     * Constructor
+     *
+     * @param string $pathname
+     * @param string $proj
+     * @param boolean $create
+     */
+    public function __construct(string $pathname, $proj="\0", bool $create=false)
+    {
+        if (!file_exists($pathname)) {
+            if (!$create) {
+                throw new \RuntimeException("Path does not exist: {$pathname}");
+            }
+            if (!is_dir(dirname($pathname))) {
+                throw new \RuntimeException("The directory ".dirname($pathname)." does not exist");
+            }
+            touch($pathname);
+        }
+
+        $this->pathname = $pathname;
+        $this->proj = substr($proj,0,1);
+    }
+
+    /**
+     * Get the pathname used to generate the key
+     *
+     * @return string
+     */
+    public function getPathname():string
+    {
+        return $this->pathname;
+    }
+
+    /**
+     * Get the project identifier. Not guaranteed to be printable
+     *
+     * @return string
+     */
+    public function getProjectIdentifier():string
+    {
+        return $this->proj;
+    }
+
+    /**
+     * Get the key value
+     *
+     * @return int
+     */
+    public function getKey():int
+    {
+        return ftok($this->pathname, $this->proj);
+    }
+
+    /**
+     * Clone the FileKey, increasing the project identifier to create a new key for the
+     * same file
+     *
+     * @return void
+     */
+    public function __clone()
+    {
+        $this->proj = chr(ord($this->proj) + 1);
+    }
+
+    /**
+     * Create printable representation of the key
+     *
+     * @return string
+     */
+    public function __toString()
+    {
+        return $this->getKey();
+    }
+}

src/Key/KeyInterface.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace NoccyLabs\Ipc\Key;
+
+interface KeyInterface
+{
+    public function getKey():int;
+    public function __toString();
+}