Update LanguageHelper.php to handle translated text with embedded new lines.

libraries/src/Language/LanguageHelper.php

@@ -404,38 +404,130 @@ public static function parseIniFile($fileName, $debug = false)
             return [];
         }
 
-        // Capture hidden PHP errors from the parsing.
-        if ($debug === true) {
-            // See https://www.php.net/manual/en/reserved.variables.phperrormsg.php
-            $php_errormsg = null;
-
-            $trackErrors = ini_get('track_errors');
-            ini_set('track_errors', true);
-        }
-
         // This was required for https://github.com/joomla/joomla-cms/issues/17198 but not sure what server setup
         // issue it is solving
         $disabledFunctions      = explode(',', ini_get('disable_functions'));
         $isParseIniFileDisabled = \in_array('parse_ini_file', array_map('trim', $disabledFunctions));
 
-        if (!\function_exists('parse_ini_file') || $isParseIniFileDisabled) {
-            $contents = file_get_contents($fileName);
-            $strings  = @parse_ini_string($contents, false, INI_SCANNER_RAW);
-        } else {
-            $strings = @parse_ini_file($fileName, false, INI_SCANNER_RAW);
-        }
+        // Capture hidden PHP errors from the parsing.
+        set_error_handler(static function ($errno, $err) {
+            throw new \Exception($err);
+        }, \E_WARNING);
+
+        try {
+            if (!\function_exists('parse_ini_file') || $isParseIniFileDisabled) {
+                $contents = file_get_contents($fileName);
+                $strings  = parse_ini_string($contents, false, INI_SCANNER_RAW);
+            } else {
+                $strings = parse_ini_file($fileName, false, INI_SCANNER_RAW);
+            }
+        } catch (\Exception $e) {
+            // Emulate Joomla 4.4.0 and earlier handling of multi-line text strings.
+            // Some developers prefer to format long descriptive strings in that way for easier maintenance.
+            // For performance reasons we only do this as a last resort as most .ini files are not affected by this.
+            $strings = self::parseMultilineIni(isset($contents) ? $contents : file_get_contents($fileName));
+
+            if ($strings === false) {
+                if ($debug) {
+                    throw new \RuntimeException($e->getMessage());
+                }
 
-        // Ini files are processed in the "RAW" mode of parse_ini_string, leaving escaped quotes untouched - lets postprocess them
-        $strings = str_replace('\"', '"', $strings);
+                return [];
+            }
 
-        // Restore error tracking to what it was before.
-        if ($debug === true) {
-            ini_set('track_errors', $trackErrors);
+            // Ini file processing has left escaped quotes untouched - let's postprocess them
+            $strings = str_replace('\"', '"', $strings);
+        } finally {
+            restore_error_handler();
         }
 
         return \is_array($strings) ? $strings : [];
     }
 
+    /**
+     * Parse strings from a language file.
+     * See issue https://github.com/joomla/joomla-cms/issues/42416
+     * Emulates Joomla v4.4.0 and earlier behaviour with multi-line text strings without the potential security concerns.
+     *
+     * @param   string   $fileName  The language ini file path.
+     * @param   boolean  $debug     If set to true debug language ini file.
+     *
+     * @return  array | false  The strings parsed.
+     *
+     * @since   __DEPLOY_VERSION__
+     */
+    protected static function parseMultilineIni($inifileContents)
+    {
+        $lines = explode("\n", $inifileContents);
+
+        $nameValuePairs = [];
+
+        for ($l=0; $l < count($lines); $l++) {
+            $line = trim($lines[$l]);
+
+            if (empty($line)) {
+                continue;
+            }
+
+            if ($line[0] == ';') {
+                continue;
+            }
+
+            $lineParts = explode('=', $line);
+            if (count($lineParts) != 2) {
+                // Unexpected file contents
+                return false;
+            }
+
+            // In case there is a space before / after =
+            $lineParts[0] = rtrim($lineParts[0]);
+            $lineParts[1] = ltrim($lineParts[1]);
+
+            // We are only expecting strings for language translation
+            if (!str_starts_with($lineParts[1], '"')) {
+                // Unexpected file contents
+                return false;
+            }
+
+            if (str_ends_with($lineParts[1], '"')) {
+                // Just in case we have a line ending with an escaped "
+                if (!str_ends_with($line, '\\"')) {
+                    if (strlen($lineParts[1]) == 2) {
+                        $nameValuePairs[$lineParts[0]] = '';
+                        continue;
+                    }
+                    $nameValuePairs[$lineParts[0]] = substr($lineParts[1], 1, strlen($lineParts[1]) - 2);
+
+                    continue;
+                }
+            }
+
+            // Found a string with embedded new lines
+            $nameValuePair = $lineParts[1];
+
+            while (++$l < count($lines)) {
+                $line = trim($lines[$l]);
+
+                $nameValuePair .= "\n" . $line;
+
+                if (str_ends_with($line, '"')) {
+                    if (!str_ends_with($line, '\\"')) {
+                        $nameValuePairs[$lineParts[0]] = substr($nameValuePair, 1, strlen($nameValuePair) - 1);
+
+                        continue 2;
+                    }
+                }
+            }
+
+            if (!str_starts_with($lineParts[1], '"')) {
+                // Unexpected file contents
+                return false;
+            }
+        }
+
+        return $nameValuePairs;
+    }
+
     /**
      * Save strings to a language file.
      *