PHP 8.1 > strftime deprecated.

2 possible workaround, use partial implementation with php date method or use IntlDateFormatter.
As symfony1 is not intended to evolve, it should not rely on currently unused PHP-Extension (nor update composer.json).

I propose a fix to replace "strftime" by "date", with a translation of format for PHP 8.1+

It will lose the ability of translating date of logs (does anybody use it ?) and it will deprecated a few strftime format (probably not used)
Performances should remains OK

I only tested it with a few formats (the default one and a few others)
If you need some missing strftime formats, please add them.

Author: Tybaze

lib/log/sfFileLogger.class.php

@@ -92,15 +92,15 @@ public function initialize(sfEventDispatcher $dispatcher, $options = array())
    * Logs a message.
    *
    * @param string $message   Message
-   * @param int    $priority  Message priority
+   * @param int $priority  Message priority
    */
   protected function doLog($message, $priority)
   {
     flock($this->fp, LOCK_EX);
     fwrite($this->fp, strtr($this->format, array(
       '%type%'     => $this->type,
       '%message%'  => $message,
-      '%time%'     => strftime($this->timeFormat),
+      '%time%'     => self::strftime($this->timeFormat),
       '%priority%' => $this->getPriority($priority),
       '%EOL%'      => PHP_EOL,
     )));
@@ -129,4 +129,60 @@ public function shutdown()
       fclose($this->fp);
     }
   }
+
+  /**
+   * @param $format
+   * @return false|string
+   */
+  public static function strftime($format)
+  {
+    if (version_compare(PHP_VERSION, '8.1.0') < 0) {
+      return strftime($format);
+    }
+    return date(self::_strftimeFormatToDateFormat($format));
+  }
+
+  /**
+   * Try to Convert a strftime to date format
+   *
+   * Unable to find a perfect implementation, based on those one (Each contains some errors)
+   * https://github.com/Fabrik/fabrik/blob/master/plugins/fabrik_element/date/date.php
+   * https://gist.github.com/mcaskill/02636e5970be1bb22270
+   * https://stackoverflow.com/questions/22665959/using-php-strftime-using-date-format-string
+   *
+   * Limitation:
+   * - Do not apply translation
+   * - Some few strftime format could be broken (low probability to be used on logs)
+   *
+   * Private: because it should not be used outside of this scope
+   *
+   * A better solution is to use : IntlDateFormatter, but it will require to load a new php extension, which could break some setup.
+   *
+   * @return array|string|string[]
+   */
+  private static function _strftimeFormatToDateFormat($strftimeFormat) {
+
+    // Missing %V %C %g %G
+    $search = array(
+      '%a', '%A', '%d', '%e', '%u',
+      '%w', '%W', '%b', '%h', '%B',
+      '%m', '%y', '%Y', '%D', '%F',
+      '%x', '%n', '%t', '%H', '%k',
+      '%I', '%l', '%M', '%p', '%P',
+      '%r' /* %I:%M:%S %p */, '%R' /* %H:%M */, '%S', '%T' /* %H:%M:%S */, '%X', '%z', '%Z',
+      '%c', '%s', '%j',
+      '%%');
+
+    $replace = array(
+      'D', 'l', 'd', 'j', 'N',
+      'w', 'W', 'M', 'M', 'F',
+      'm', 'y', 'Y', 'm/d/y', 'Y-m-d',
+      'm/d/y', "\n", "\t", 'H', 'G',
+      'h', 'g', 'i', 'A', 'a',
+      'h:i:s A', 'H:i', 's', 'H:i:s', 'H:i:s', 'O', 'T',
+      'D M j H:i:s Y' /*Tue Feb 5 00:45:10 2009*/, 'U', 'z',
+      '%');
+
+    return str_replace($search, $replace, $strftimeFormat);
+  }
 }

test/unit/log/sfFileLoggerTest.php

@@ -3,7 +3,7 @@
 /*
  * This file is part of the symfony package.
  * (c) 2004-2006 Fabien Potencier <fabien.potencier@symfony-project.com>
- * 
+ *
  * For the full copyright and license information, please view the LICENSE
  * file that was distributed with this source code.
  */
@@ -61,7 +61,7 @@ protected function getPriority($priority)
 unlink($file);
 $logger = new TestLogger($dispatcher, array('file' => $file));
 $logger->log('foo');
-$t->is(file_get_contents($file), strftime($logger->getTimeFormat()).' symfony [*6*] foo'.PHP_EOL, '->initialize() can take a format option');
+$t->is(file_get_contents($file), TestLogger::strftime($logger->getTimeFormat()).' symfony [*6*] foo'.PHP_EOL, '->initialize() can take a format option');
 
 unlink($file);
 $logger = new TestLogger($dispatcher, array('file' => $file, 'format' => '%message%'));
@@ -73,14 +73,14 @@ protected function getPriority($priority)
 unlink($file);
 $logger = new TestLogger($dispatcher, array('file' => $file, 'time_format' => '%Y %m %d'));
 $logger->log('foo');
-$t->is(file_get_contents($file), strftime($logger->getTimeFormat()).' symfony [*6*] foo'.PHP_EOL, '->initialize() can take a format option');
+$t->is(file_get_contents($file), TestLogger::strftime($logger->getTimeFormat()).' symfony [*6*] foo'.PHP_EOL, '->initialize() can take a format option');
 
 // option: type
 $t->diag('option: type');
 unlink($file);
 $logger = new TestLogger($dispatcher, array('file' => $file, 'type' => 'foo'));
 $logger->log('foo');
-$t->is(file_get_contents($file), strftime($logger->getTimeFormat()).' foo [*6*] foo'.PHP_EOL, '->initialize() can take a format option');
+$t->is(file_get_contents($file), TestLogger::strftime($logger->getTimeFormat()).' foo [*6*] foo'.PHP_EOL, '->initialize() can take a format option');
 
 // ->shutdown()
 $t->diag('->shutdown()');