Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\Component\Utility;
Chris@0: 
Chris@0: /**
Chris@0:  * Provides PHP environment helper methods.
Chris@0:  */
Chris@0: class Environment {
Chris@0: 
Chris@0:   /**
Chris@0:    * Compares the memory required for an operation to the available memory.
Chris@0:    *
Chris@0:    * @param string $required
Chris@0:    *   The memory required for the operation, expressed as a number of bytes with
Chris@0:    *   optional SI or IEC binary unit prefix (e.g. 2, 3K, 5MB, 10G, 6GiB, 8bytes,
Chris@0:    *   9mbytes).
Chris@0:    * @param $memory_limit
Chris@0:    *   (optional) The memory limit for the operation, expressed as a number of
Chris@0:    *   bytes with optional SI or IEC binary unit prefix (e.g. 2, 3K, 5MB, 10G,
Chris@0:    *   6GiB, 8bytes, 9mbytes). If no value is passed, the current PHP
Chris@0:    *   memory_limit will be used. Defaults to NULL.
Chris@0:    *
Chris@0:    * @return bool
Chris@0:    *   TRUE if there is sufficient memory to allow the operation, or FALSE
Chris@0:    *   otherwise.
Chris@0:    */
Chris@0:   public static function checkMemoryLimit($required, $memory_limit = NULL) {
Chris@0:     if (!isset($memory_limit)) {
Chris@0:       $memory_limit = ini_get('memory_limit');
Chris@0:     }
Chris@0: 
Chris@0:     // There is sufficient memory if:
Chris@0:     // - No memory limit is set.
Chris@0:     // - The memory limit is set to unlimited (-1).
Chris@0:     // - The memory limit is greater than or equal to the memory required for
Chris@0:     //   the operation.
Chris@0:     return ((!$memory_limit) || ($memory_limit == -1) || (Bytes::toInt($memory_limit) >= Bytes::toInt($required)));
Chris@0:   }
Chris@0: 
Chris@18:   /**
Chris@18:    * Attempts to set the PHP maximum execution time.
Chris@18:    *
Chris@18:    * This function is a wrapper around the PHP function set_time_limit(). When
Chris@18:    * called, set_time_limit() restarts the timeout counter from zero. In other
Chris@18:    * words, if the timeout is the default 30 seconds, and 25 seconds into script
Chris@18:    * execution a call such as set_time_limit(20) is made, the script will run
Chris@18:    * for a total of 45 seconds before timing out.
Chris@18:    *
Chris@18:    * If the current time limit is not unlimited it is possible to decrease the
Chris@18:    * total time limit if the sum of the new time limit and the current time
Chris@18:    * spent running the script is inferior to the original time limit. It is
Chris@18:    * inherent to the way set_time_limit() works, it should rather be called with
Chris@18:    * an appropriate value every time you need to allocate a certain amount of
Chris@18:    * time to execute a task than only once at the beginning of the script.
Chris@18:    *
Chris@18:    * Before calling set_time_limit(), we check if this function is available
Chris@18:    * because it could be disabled by the server administrator.
Chris@18:    *
Chris@18:    * @param int $time_limit
Chris@18:    *   An integer time limit in seconds, or 0 for unlimited execution time.
Chris@18:    *
Chris@18:    * @return bool
Chris@18:    *   Whether set_time_limit() was successful or not.
Chris@18:    */
Chris@18:   public static function setTimeLimit($time_limit) {
Chris@18:     if (function_exists('set_time_limit')) {
Chris@18:       $current = ini_get('max_execution_time');
Chris@18:       // Do not set time limit if it is currently unlimited.
Chris@18:       if ($current != 0) {
Chris@18:         return set_time_limit($time_limit);
Chris@18:       }
Chris@18:     }
Chris@18:     return FALSE;
Chris@18:   }
Chris@18: 
Chris@18:   /**
Chris@18:    * Determines the maximum file upload size by querying the PHP settings.
Chris@18:    *
Chris@18:    * @return int
Chris@18:    *   A file size limit in bytes based on the PHP upload_max_filesize and
Chris@18:    *   post_max_size settings.
Chris@18:    */
Chris@18:   public static function getUploadMaxSize() {
Chris@18:     static $max_size = -1;
Chris@18: 
Chris@18:     if ($max_size < 0) {
Chris@18:       // Start with post_max_size.
Chris@18:       $max_size = Bytes::toInt(ini_get('post_max_size'));
Chris@18: 
Chris@18:       // If upload_max_size is less, then reduce. Except if upload_max_size is
Chris@18:       // zero, which indicates no limit.
Chris@18:       $upload_max = Bytes::toInt(ini_get('upload_max_filesize'));
Chris@18:       if ($upload_max > 0 && $upload_max < $max_size) {
Chris@18:         $max_size = $upload_max;
Chris@18:       }
Chris@18:     }
Chris@18:     return $max_size;
Chris@18:   }
Chris@18: 
Chris@0: }