From 26265f0b76e8f8e69af643bfefdb9d40090942af Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Kure=C4=8Dka?= <danielkurecka@gmail.com>
Date: Tue, 23 Nov 2021 23:48:02 +0100
Subject: [PATCH] Use random available port rather than randomly generated one

---
 .../Instance/Launcher.php                     | 23 +++++++++++++------
 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/src/ChromeDevtoolsProtocol/Instance/Launcher.php b/src/ChromeDevtoolsProtocol/Instance/Launcher.php
index 6794aaa4..7c02f6bc 100644
--- a/src/ChromeDevtoolsProtocol/Instance/Launcher.php
+++ b/src/ChromeDevtoolsProtocol/Instance/Launcher.php
@@ -40,16 +40,11 @@ class Launcher
 	private $input;
 
 	/**
-	 * @param int $port If port <= 0, random port number is generated.
-	 * @throws \Exception
+	 * @param int $port If port <= 0, random available port is used.
 	 */
 	public function __construct($port = 0)
 	{
-		if ($port <= 0) {
-			$port = random_int(1024 + 1, 65535);
-		}
-
-		$this->port = $port;
+		$this->port = max(0, $port);
 	}
 
 	/**
@@ -212,6 +207,10 @@ private function launchWithExecutable(ContextInterface $ctx, string $executable,
 		$temporaryUserDataDir = null;
 		if (!$foundUserDataDir) {
 			$temporaryUserDataDir = sys_get_temp_dir() . DIRECTORY_SEPARATOR . "chrome-profile-" . $this->port;
+			if ($this->port === 0) {
+				$temporaryUserDataDir .= "-" . bin2hex(random_bytes(8));
+			}
+
 			$fs->mkdir($temporaryUserDataDir);
 			$args[] = "--user-data-dir=" . $temporaryUserDataDir;
 		}
@@ -226,6 +225,16 @@ private function launchWithExecutable(ContextInterface $ctx, string $executable,
 			);
 			$process->start();
 
+			if ($this->port === 0) {
+				$process->waitUntil(function ($type, $buffer)  {
+					if (preg_match('~DevTools listening on ws://.+:(\d+)/devtools~', $buffer, $m)) {
+						$this->port = (int)$m[1];
+						return true;
+					}
+					return false;
+				});
+			}
+
 			$instance = new ProcessInstance($process, $temporaryUserDataDir, $this->port);
 
 			for (; ;) {