Escape single quotes and backslashes

src/Core/Config/Util/ConfigFileTransformer.php

@@ -75,7 +75,7 @@ class ConfigFileTransformer
 		} elseif (is_numeric($value)) {
 			$string .= $value . ",";
 		} else {
-			$string .= sprintf('\'%s\',', $value);
+			$string .= sprintf('\'%s\',', addcslashes($value, '\'\\'));
 		}
 
 		$string .= PHP_EOL;

tests/datasets/config/B.node.config.php

@@ -34,5 +34,6 @@ return [
 		'theme' => 'frio',
 		'int' => 23,
 		'float' => 2.5,
+		'with special chars' => 'I can\'t follow this "$&§%"$%§$%&\'[),',
 	],
 ];

tests/src/Core/Config/Cache/ConfigFileManagerTest.php

@@ -28,7 +28,7 @@ use Friendica\Test\Util\VFSTrait;
 use Friendica\Core\Config\Util\ConfigFileManager;
 use org\bovigo\vfs\vfsStream;
 
-class ConfigFileLoaderTest extends MockedTest
+class ConfigFileManagerTest extends MockedTest
 {
 	use VFSTrait;
 
@@ -407,10 +407,13 @@ class ConfigFileLoaderTest extends MockedTest
 
 		$configFileLoader->setupCache($configCache);
 
+		$specialChars = '!"§$%&/()(/&%$\'><?$a,;:[]}{}\\';
+
 		// overwrite some data and save it back to the config file
 		$configCache->set('system', 'test', 'it', Cache::SOURCE_DATA);
 		$configCache->set('config', 'test', 'it', Cache::SOURCE_DATA);
 		$configCache->set('system', 'test_2', 2, Cache::SOURCE_DATA);
+		$configCache->set('special_chars', 'special', $specialChars, Cache::SOURCE_DATA);
 		$configFileLoader->saveData($configCache);
 
 		// Reload the configCache with the new values
@@ -424,7 +427,10 @@ class ConfigFileLoaderTest extends MockedTest
 				'test_2' => 2
 			],
 			'config' => [
-				'test' => 'it'
+				'test' => 'it',
+			],
+			'special_chars' => [
+				'special' => $specialChars,
 			]], $configCache2->getDataBySource(Cache::SOURCE_DATA));
 	}
 }