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   1  <?php
   2  /**
   3   * WordPress Cron API
   4   *
   5   * @package WordPress
   6   */
   7  
   8  /**
   9   * Schedules an event to run only once.
  10   *
  11   * Schedules a hook which will be triggered by WordPress at the specified time.
  12   * The action will trigger when someone visits your WordPress site if the scheduled
  13   * time has passed.
  14   *
  15   * Note that scheduling an event to occur within 10 minutes of an existing event
  16   * with the same action hook will be ignored unless you pass unique `$args` values
  17   * for each scheduled event.
  18   *
  19   * Use wp_next_scheduled() to prevent duplicate events.
  20   *
  21   * Use wp_schedule_event() to schedule a recurring event.
  22   *
  23   * @since 2.1.0
  24   * @since 5.1.0 Return value modified to boolean indicating success or failure,
  25   *              {@see 'pre_schedule_event'} filter added to short-circuit the function.
  26   *
  27   * @link https://developer.wordpress.org/reference/functions/wp_schedule_single_event/
  28   *
  29   * @param int    $timestamp  Unix timestamp (UTC) for when to next run the event.
  30   * @param string $hook       Action hook to execute when the event is run.
  31   * @param array  $args       Optional. Array containing arguments to pass to the
  32   *                           hook's callback function. Each value in the array is passed
  33   *                           to the callback as an individual parameter. The array keys
  34   *                           are ignored. Default: empty array.
  35   * @return bool True if event successfully scheduled. False for failure.
  36   */
  37  function wp_schedule_single_event( $timestamp, $hook, $args = array() ) {
  38      // Make sure timestamp is a positive integer.
  39      if ( ! is_numeric( $timestamp ) || $timestamp <= 0 ) {
  40          return false;
  41      }
  42  
  43      $event = (object) array(
  44          'hook'      => $hook,
  45          'timestamp' => $timestamp,
  46          'schedule'  => false,
  47          'args'      => $args,
  48      );
  49  
  50      /**
  51       * Filter to preflight or hijack scheduling an event.
  52       *
  53       * Returning a non-null value will short-circuit adding the event to the
  54       * cron array, causing the function to return the filtered value instead.
  55       *
  56       * Both single events and recurring events are passed through this filter;
  57       * single events have `$event->schedule` as false, whereas recurring events
  58       * have this set to a recurrence from wp_get_schedules(). Recurring
  59       * events also have the integer recurrence interval set as `$event->interval`.
  60       *
  61       * For plugins replacing wp-cron, it is recommended you check for an
  62       * identical event within ten minutes and apply the {@see 'schedule_event'}
  63       * filter to check if another plugin has disallowed the event before scheduling.
  64       *
  65       * Return true if the event was scheduled, false if not.
  66       *
  67       * @since 5.1.0
  68       *
  69       * @param null|bool $pre   Value to return instead. Default null to continue adding the event.
  70       * @param stdClass  $event {
  71       *     An object containing an event's data.
  72       *
  73       *     @type string       $hook      Action hook to execute when the event is run.
  74       *     @type int          $timestamp Unix timestamp (UTC) for when to next run the event.
  75       *     @type string|false $schedule  How often the event should subsequently recur.
  76       *     @type array        $args      Array containing each separate argument to pass to the hook's callback function.
  77       *     @type int          $interval  The interval time in seconds for the schedule. Only present for recurring events.
  78       * }
  79       */
  80      $pre = apply_filters( 'pre_schedule_event', null, $event );
  81      if ( null !== $pre ) {
  82          return $pre;
  83      }
  84  
  85      /*
  86       * Check for a duplicated event.
  87       *
  88       * Don't schedule an event if there's already an identical event
  89       * within 10 minutes.
  90       *
  91       * When scheduling events within ten minutes of the current time,
  92       * all past identical events are considered duplicates.
  93       *
  94       * When scheduling an event with a past timestamp (ie, before the
  95       * current time) all events scheduled within the next ten minutes
  96       * are considered duplicates.
  97       */
  98      $crons     = (array) _get_cron_array();
  99      $key       = md5( serialize( $event->args ) );
 100      $duplicate = false;
 101  
 102      if ( $event->timestamp < time() + 10 * MINUTE_IN_SECONDS ) {
 103          $min_timestamp = 0;
 104      } else {
 105          $min_timestamp = $event->timestamp - 10 * MINUTE_IN_SECONDS;
 106      }
 107  
 108      if ( $event->timestamp < time() ) {
 109          $max_timestamp = time() + 10 * MINUTE_IN_SECONDS;
 110      } else {
 111          $max_timestamp = $event->timestamp + 10 * MINUTE_IN_SECONDS;
 112      }
 113  
 114      foreach ( $crons as $event_timestamp => $cron ) {
 115          if ( $event_timestamp < $min_timestamp ) {
 116              continue;
 117          }
 118          if ( $event_timestamp > $max_timestamp ) {
 119              break;
 120          }
 121          if ( isset( $cron[ $event->hook ][ $key ] ) ) {
 122              $duplicate = true;
 123              break;
 124          }
 125      }
 126  
 127      if ( $duplicate ) {
 128          return false;
 129      }
 130  
 131      /**
 132       * Modify an event before it is scheduled.
 133       *
 134       * @since 3.1.0
 135       *
 136       * @param stdClass|false $event {
 137       *     An object containing an event's data, or boolean false to prevent the event from being scheduled.
 138       *
 139       *     @type string       $hook      Action hook to execute when the event is run.
 140       *     @type int          $timestamp Unix timestamp (UTC) for when to next run the event.
 141       *     @type string|false $schedule  How often the event should subsequently recur.
 142       *     @type array        $args      Array containing each separate argument to pass to the hook's callback function.
 143       *     @type int          $interval  The interval time in seconds for the schedule. Only present for recurring events.
 144       * }
 145       */
 146      $event = apply_filters( 'schedule_event', $event );
 147  
 148      // A plugin disallowed this event.
 149      if ( ! $event ) {
 150          return false;
 151      }
 152  
 153      $crons[ $event->timestamp ][ $event->hook ][ $key ] = array(
 154          'schedule' => $event->schedule,
 155          'args'     => $event->args,
 156      );
 157      uksort( $crons, 'strnatcasecmp' );
 158      return _set_cron_array( $crons );
 159  }
 160  
 161  /**
 162   * Schedules a recurring event.
 163   *
 164   * Schedules a hook which will be triggered by WordPress at the specified interval.
 165   * The action will trigger when someone visits your WordPress site if the scheduled
 166   * time has passed.
 167   *
 168   * Valid values for the recurrence are 'hourly', 'daily', and 'twicedaily'. These can
 169   * be extended using the {@see 'cron_schedules'} filter in wp_get_schedules().
 170   *
 171   * Note that scheduling an event to occur within 10 minutes of an existing event
 172   * with the same action hook will be ignored unless you pass unique `$args` values
 173   * for each scheduled event.
 174   *
 175   * Use wp_next_scheduled() to prevent duplicate events.
 176   *
 177   * Use wp_schedule_single_event() to schedule a non-recurring event.
 178   *
 179   * @since 2.1.0
 180   * @since 5.1.0 Return value modified to boolean indicating success or failure,
 181   *              {@see 'pre_schedule_event'} filter added to short-circuit the function.
 182   *
 183   * @link https://developer.wordpress.org/reference/functions/wp_schedule_event/
 184   *
 185   * @param int    $timestamp  Unix timestamp (UTC) for when to next run the event.
 186   * @param string $recurrence How often the event should subsequently recur.
 187   *                           See wp_get_schedules() for accepted values.
 188   * @param string $hook       Action hook to execute when the event is run.
 189   * @param array  $args       Optional. Array containing arguments to pass to the
 190   *                           hook's callback function. Each value in the array is passed
 191   *                           to the callback as an individual parameter. The array keys
 192   *                           are ignored. Default: empty array.
 193   * @return bool True if event successfully scheduled. False for failure.
 194   */
 195  function wp_schedule_event( $timestamp, $recurrence, $hook, $args = array() ) {
 196      // Make sure timestamp is a positive integer.
 197      if ( ! is_numeric( $timestamp ) || $timestamp <= 0 ) {
 198          return false;
 199      }
 200  
 201      $schedules = wp_get_schedules();
 202  
 203      if ( ! isset( $schedules[ $recurrence ] ) ) {
 204          return false;
 205      }
 206  
 207      $event = (object) array(
 208          'hook'      => $hook,
 209          'timestamp' => $timestamp,
 210          'schedule'  => $recurrence,
 211          'args'      => $args,
 212          'interval'  => $schedules[ $recurrence ]['interval'],
 213      );
 214  
 215      /** This filter is documented in wp-includes/cron.php */
 216      $pre = apply_filters( 'pre_schedule_event', null, $event );
 217      if ( null !== $pre ) {
 218          return $pre;
 219      }
 220  
 221      /** This filter is documented in wp-includes/cron.php */
 222      $event = apply_filters( 'schedule_event', $event );
 223  
 224      // A plugin disallowed this event.
 225      if ( ! $event ) {
 226          return false;
 227      }
 228  
 229      $key = md5( serialize( $event->args ) );
 230  
 231      $crons = _get_cron_array();
 232      $crons[ $event->timestamp ][ $event->hook ][ $key ] = array(
 233          'schedule' => $event->schedule,
 234          'args'     => $event->args,
 235          'interval' => $event->interval,
 236      );
 237      uksort( $crons, 'strnatcasecmp' );
 238      return _set_cron_array( $crons );
 239  }
 240  
 241  /**
 242   * Reschedules a recurring event.
 243   *
 244   * Mainly for internal use, this takes the time stamp of a previously run
 245   * recurring event and reschedules it for its next run.
 246   *
 247   * To change upcoming scheduled events, use wp_schedule_event() to
 248   * change the recurrence frequency.
 249   *
 250   * @since 2.1.0
 251   * @since 5.1.0 Return value modified to boolean indicating success or failure,
 252   *              {@see 'pre_reschedule_event'} filter added to short-circuit the function.
 253   *
 254   * @param int    $timestamp  Unix timestamp (UTC) for when the event was scheduled.
 255   * @param string $recurrence How often the event should subsequently recur.
 256   *                           See wp_get_schedules() for accepted values.
 257   * @param string $hook       Action hook to execute when the event is run.
 258   * @param array  $args       Optional. Array containing arguments to pass to the
 259   *                           hook's callback function. Each value in the array is passed
 260   *                           to the callback as an individual parameter. The array keys
 261   *                           are ignored. Default: empty array.
 262   * @return bool True if event successfully rescheduled. False for failure.
 263   */
 264  function wp_reschedule_event( $timestamp, $recurrence, $hook, $args = array() ) {
 265      // Make sure timestamp is a positive integer.
 266      if ( ! is_numeric( $timestamp ) || $timestamp <= 0 ) {
 267          return false;
 268      }
 269  
 270      $schedules = wp_get_schedules();
 271      $interval  = 0;
 272  
 273      // First we try to get the interval from the schedule.
 274      if ( isset( $schedules[ $recurrence ] ) ) {
 275          $interval = $schedules[ $recurrence ]['interval'];
 276      }
 277  
 278      // Now we try to get it from the saved interval in case the schedule disappears.
 279      if ( 0 === $interval ) {
 280          $scheduled_event = wp_get_scheduled_event( $hook, $args, $timestamp );
 281          if ( $scheduled_event && isset( $scheduled_event->interval ) ) {
 282              $interval = $scheduled_event->interval;
 283          }
 284      }
 285  
 286      $event = (object) array(
 287          'hook'      => $hook,
 288          'timestamp' => $timestamp,
 289          'schedule'  => $recurrence,
 290          'args'      => $args,
 291          'interval'  => $interval,
 292      );
 293  
 294      /**
 295       * Filter to preflight or hijack rescheduling of events.
 296       *
 297       * Returning a non-null value will short-circuit the normal rescheduling
 298       * process, causing the function to return the filtered value instead.
 299       *
 300       * For plugins replacing wp-cron, return true if the event was successfully
 301       * rescheduled, false if not.
 302       *
 303       * @since 5.1.0
 304       *
 305       * @param null|bool $pre   Value to return instead. Default null to continue adding the event.
 306       * @param stdClass  $event {
 307       *     An object containing an event's data.
 308       *
 309       *     @type string       $hook      Action hook to execute when the event is run.
 310       *     @type int          $timestamp Unix timestamp (UTC) for when to next run the event.
 311       *     @type string|false $schedule  How often the event should subsequently recur.
 312       *     @type array        $args      Array containing each separate argument to pass to the hook's callback function.
 313       *     @type int          $interval  The interval time in seconds for the schedule. Only present for recurring events.
 314       * }
 315       */
 316      $pre = apply_filters( 'pre_reschedule_event', null, $event );
 317      if ( null !== $pre ) {
 318          return $pre;
 319      }
 320  
 321      // Now we assume something is wrong and fail to schedule.
 322      if ( 0 == $interval ) {
 323          return false;
 324      }
 325  
 326      $now = time();
 327  
 328      if ( $timestamp >= $now ) {
 329          $timestamp = $now + $interval;
 330      } else {
 331          $timestamp = $now + ( $interval - ( ( $now - $timestamp ) % $interval ) );
 332      }
 333  
 334      return wp_schedule_event( $timestamp, $recurrence, $hook, $args );
 335  }
 336  
 337  /**
 338   * Unschedule a previously scheduled event.
 339   *
 340   * The $timestamp and $hook parameters are required so that the event can be
 341   * identified.
 342   *
 343   * @since 2.1.0
 344   * @since 5.1.0 Return value modified to boolean indicating success or failure,
 345   *              {@see 'pre_unschedule_event'} filter added to short-circuit the function.
 346   *
 347   * @param int    $timestamp Unix timestamp (UTC) of the event.
 348   * @param string $hook      Action hook of the event.
 349   * @param array  $args      Optional. Array containing each separate argument to pass to the hook's callback function.
 350   *                          Although not passed to a callback, these arguments are used to uniquely identify the
 351   *                          event, so they should be the same as those used when originally scheduling the event.
 352   * @return bool True if event successfully unscheduled. False for failure.
 353   */
 354  function wp_unschedule_event( $timestamp, $hook, $args = array() ) {
 355      // Make sure timestamp is a positive integer.
 356      if ( ! is_numeric( $timestamp ) || $timestamp <= 0 ) {
 357          return false;
 358      }
 359  
 360      /**
 361       * Filter to preflight or hijack unscheduling of events.
 362       *
 363       * Returning a non-null value will short-circuit the normal unscheduling
 364       * process, causing the function to return the filtered value instead.
 365       *
 366       * For plugins replacing wp-cron, return true if the event was successfully
 367       * unscheduled, false if not.
 368       *
 369       * @since 5.1.0
 370       *
 371       * @param null|bool $pre       Value to return instead. Default null to continue unscheduling the event.
 372       * @param int       $timestamp Timestamp for when to run the event.
 373       * @param string    $hook      Action hook, the execution of which will be unscheduled.
 374       * @param array     $args      Arguments to pass to the hook's callback function.
 375       */
 376      $pre = apply_filters( 'pre_unschedule_event', null, $timestamp, $hook, $args );
 377      if ( null !== $pre ) {
 378          return $pre;
 379      }
 380  
 381      $crons = _get_cron_array();
 382      $key   = md5( serialize( $args ) );
 383      unset( $crons[ $timestamp ][ $hook ][ $key ] );
 384      if ( empty( $crons[ $timestamp ][ $hook ] ) ) {
 385          unset( $crons[ $timestamp ][ $hook ] );
 386      }
 387      if ( empty( $crons[ $timestamp ] ) ) {
 388          unset( $crons[ $timestamp ] );
 389      }
 390      return _set_cron_array( $crons );
 391  }
 392  
 393  /**
 394   * Unschedules all events attached to the hook with the specified arguments.
 395   *
 396   * Warning: This function may return Boolean FALSE, but may also return a non-Boolean
 397   * value which evaluates to FALSE. For information about casting to booleans see the
 398   * {@link https://www.php.net/manual/en/language.types.boolean.php PHP documentation}. Use
 399   * the `===` operator for testing the return value of this function.
 400   *
 401   * @since 2.1.0
 402   * @since 5.1.0 Return value modified to indicate success or failure,
 403   *              {@see 'pre_clear_scheduled_hook'} filter added to short-circuit the function.
 404   *
 405   * @param string $hook Action hook, the execution of which will be unscheduled.
 406   * @param array  $args Optional. Array containing each separate argument to pass to the hook's callback function.
 407   *                     Although not passed to a callback, these arguments are used to uniquely identify the
 408   *                     event, so they should be the same as those used when originally scheduling the event.
 409   * @return int|false On success an integer indicating number of events unscheduled (0 indicates no
 410   *                   events were registered with the hook and arguments combination), false if
 411   *                   unscheduling one or more events fail.
 412   */
 413  function wp_clear_scheduled_hook( $hook, $args = array() ) {
 414      // Backward compatibility.
 415      // Previously, this function took the arguments as discrete vars rather than an array like the rest of the API.
 416      if ( ! is_array( $args ) ) {
 417          _deprecated_argument( __FUNCTION__, '3.0.0', __( 'This argument has changed to an array to match the behavior of the other cron functions.' ) );
 418          $args = array_slice( func_get_args(), 1 ); // phpcs:ignore PHPCompatibility.FunctionUse.ArgumentFunctionsReportCurrentValue.NeedsInspection
 419      }
 420  
 421      /**
 422       * Filter to preflight or hijack clearing a scheduled hook.
 423       *
 424       * Returning a non-null value will short-circuit the normal unscheduling
 425       * process, causing the function to return the filtered value instead.
 426       *
 427       * For plugins replacing wp-cron, return the number of events successfully
 428       * unscheduled (zero if no events were registered with the hook) or false
 429       * if unscheduling one or more events fails.
 430       *
 431       * @since 5.1.0
 432       *
 433       * @param null|int|false $pre  Value to return instead. Default null to continue unscheduling the event.
 434       * @param string         $hook Action hook, the execution of which will be unscheduled.
 435       * @param array          $args Arguments to pass to the hook's callback function.
 436       */
 437      $pre = apply_filters( 'pre_clear_scheduled_hook', null, $hook, $args );
 438      if ( null !== $pre ) {
 439          return $pre;
 440      }
 441  
 442      /*
 443       * This logic duplicates wp_next_scheduled().
 444       * It's required due to a scenario where wp_unschedule_event() fails due to update_option() failing,
 445       * and, wp_next_scheduled() returns the same schedule in an infinite loop.
 446       */
 447      $crons = _get_cron_array();
 448      if ( empty( $crons ) ) {
 449          return 0;
 450      }
 451  
 452      $results = array();
 453      $key     = md5( serialize( $args ) );
 454      foreach ( $crons as $timestamp => $cron ) {
 455          if ( isset( $cron[ $hook ][ $key ] ) ) {
 456              $results[] = wp_unschedule_event( $timestamp, $hook, $args );
 457          }
 458      }
 459      if ( in_array( false, $results, true ) ) {
 460          return false;
 461      }
 462      return count( $results );
 463  }
 464  
 465  /**
 466   * Unschedules all events attached to the hook.
 467   *
 468   * Can be useful for plugins when deactivating to clean up the cron queue.
 469   *
 470   * Warning: This function may return Boolean FALSE, but may also return a non-Boolean
 471   * value which evaluates to FALSE. For information about casting to booleans see the
 472   * {@link https://www.php.net/manual/en/language.types.boolean.php PHP documentation}. Use
 473   * the `===` operator for testing the return value of this function.
 474   *
 475   * @since 4.9.0
 476   * @since 5.1.0 Return value added to indicate success or failure.
 477   *
 478   * @param string $hook Action hook, the execution of which will be unscheduled.
 479   * @return int|false On success an integer indicating number of events unscheduled (0 indicates no
 480   *                   events were registered on the hook), false if unscheduling fails.
 481   */
 482  function wp_unschedule_hook( $hook ) {
 483      /**
 484       * Filter to preflight or hijack clearing all events attached to the hook.
 485       *
 486       * Returning a non-null value will short-circuit the normal unscheduling
 487       * process, causing the function to return the filtered value instead.
 488       *
 489       * For plugins replacing wp-cron, return the number of events successfully
 490       * unscheduled (zero if no events were registered with the hook) or false
 491       * if unscheduling one or more events fails.
 492       *
 493       * @since 5.1.0
 494       *
 495       * @param null|int|false $pre  Value to return instead. Default null to continue unscheduling the hook.
 496       * @param string         $hook Action hook, the execution of which will be unscheduled.
 497       */
 498      $pre = apply_filters( 'pre_unschedule_hook', null, $hook );
 499      if ( null !== $pre ) {
 500          return $pre;
 501      }
 502  
 503      $crons = _get_cron_array();
 504      if ( empty( $crons ) ) {
 505          return 0;
 506      }
 507  
 508      $results = array();
 509      foreach ( $crons as $timestamp => $args ) {
 510          if ( ! empty( $crons[ $timestamp ][ $hook ] ) ) {
 511              $results[] = count( $crons[ $timestamp ][ $hook ] );
 512          }
 513          unset( $crons[ $timestamp ][ $hook ] );
 514  
 515          if ( empty( $crons[ $timestamp ] ) ) {
 516              unset( $crons[ $timestamp ] );
 517          }
 518      }
 519  
 520      /*
 521       * If the results are empty (zero events to unschedule), no attempt
 522       * to update the cron array is required.
 523       */
 524      if ( empty( $results ) ) {
 525          return 0;
 526      }
 527      if ( _set_cron_array( $crons ) ) {
 528          return array_sum( $results );
 529      }
 530      return false;
 531  }
 532  
 533  /**
 534   * Retrieve a scheduled event.
 535   *
 536   * Retrieve the full event object for a given event, if no timestamp is specified the next
 537   * scheduled event is returned.
 538   *
 539   * @since 5.1.0
 540   *
 541   * @param string   $hook      Action hook of the event.
 542   * @param array    $args      Optional. Array containing each separate argument to pass to the hook's callback function.
 543   *                            Although not passed to a callback, these arguments are used to uniquely identify the
 544   *                            event, so they should be the same as those used when originally scheduling the event.
 545   * @param int|null $timestamp Optional. Unix timestamp (UTC) of the event. If not specified, the next scheduled event is returned.
 546   * @return object|false The event object. False if the event does not exist.
 547   */
 548  function wp_get_scheduled_event( $hook, $args = array(), $timestamp = null ) {
 549      /**
 550       * Filter to preflight or hijack retrieving a scheduled event.
 551       *
 552       * Returning a non-null value will short-circuit the normal process,
 553       * returning the filtered value instead.
 554       *
 555       * Return false if the event does not exist, otherwise an event object
 556       * should be returned.
 557       *
 558       * @since 5.1.0
 559       *
 560       * @param null|false|object $pre  Value to return instead. Default null to continue retrieving the event.
 561       * @param string            $hook Action hook of the event.
 562       * @param array             $args Array containing each separate argument to pass to the hook's callback function.
 563       *                                Although not passed to a callback, these arguments are used to uniquely identify
 564       *                                the event.
 565       * @param int|null  $timestamp Unix timestamp (UTC) of the event. Null to retrieve next scheduled event.
 566       */
 567      $pre = apply_filters( 'pre_get_scheduled_event', null, $hook, $args, $timestamp );
 568      if ( null !== $pre ) {
 569          return $pre;
 570      }
 571  
 572      if ( null !== $timestamp && ! is_numeric( $timestamp ) ) {
 573          return false;
 574      }
 575  
 576      $crons = _get_cron_array();
 577      if ( empty( $crons ) ) {
 578          return false;
 579      }
 580  
 581      $key = md5( serialize( $args ) );
 582  
 583      if ( ! $timestamp ) {
 584          // Get next event.
 585          $next = false;
 586          foreach ( $crons as $timestamp => $cron ) {
 587              if ( isset( $cron[ $hook ][ $key ] ) ) {
 588                  $next = $timestamp;
 589                  break;
 590              }
 591          }
 592          if ( ! $next ) {
 593              return false;
 594          }
 595  
 596          $timestamp = $next;
 597      } elseif ( ! isset( $crons[ $timestamp ][ $hook ][ $key ] ) ) {
 598          return false;
 599      }
 600  
 601      $event = (object) array(
 602          'hook'      => $hook,
 603          'timestamp' => $timestamp,
 604          'schedule'  => $crons[ $timestamp ][ $hook ][ $key ]['schedule'],
 605          'args'      => $args,
 606      );
 607  
 608      if ( isset( $crons[ $timestamp ][ $hook ][ $key ]['interval'] ) ) {
 609          $event->interval = $crons[ $timestamp ][ $hook ][ $key ]['interval'];
 610      }
 611  
 612      return $event;
 613  }
 614  
 615  /**
 616   * Retrieve the next timestamp for an event.
 617   *
 618   * @since 2.1.0
 619   *
 620   * @param string $hook Action hook of the event.
 621   * @param array  $args Optional. Array containing each separate argument to pass to the hook's callback function.
 622   *                     Although not passed to a callback, these arguments are used to uniquely identify the
 623   *                     event, so they should be the same as those used when originally scheduling the event.
 624   * @return int|false The Unix timestamp of the next time the event will occur. False if the event doesn't exist.
 625   */
 626  function wp_next_scheduled( $hook, $args = array() ) {
 627      $next_event = wp_get_scheduled_event( $hook, $args );
 628      if ( ! $next_event ) {
 629          return false;
 630      }
 631  
 632      return $next_event->timestamp;
 633  }
 634  
 635  /**
 636   * Sends a request to run cron through HTTP request that doesn't halt page loading.
 637   *
 638   * @since 2.1.0
 639   * @since 5.1.0 Return values added.
 640   *
 641   * @param int $gmt_time Optional. Unix timestamp (UTC). Default 0 (current time is used).
 642   * @return bool True if spawned, false if no events spawned.
 643   */
 644  function spawn_cron( $gmt_time = 0 ) {
 645      if ( ! $gmt_time ) {
 646          $gmt_time = microtime( true );
 647      }
 648  
 649      if ( defined( 'DOING_CRON' ) || isset( $_GET['doing_wp_cron'] ) ) {
 650          return false;
 651      }
 652  
 653      /*
 654       * Get the cron lock, which is a Unix timestamp of when the last cron was spawned
 655       * and has not finished running.
 656       *
 657       * Multiple processes on multiple web servers can run this code concurrently,
 658       * this lock attempts to make spawning as atomic as possible.
 659       */
 660      $lock = get_transient( 'doing_cron' );
 661  
 662      if ( $lock > $gmt_time + 10 * MINUTE_IN_SECONDS ) {
 663          $lock = 0;
 664      }
 665  
 666      // Don't run if another process is currently running it or more than once every 60 sec.
 667      if ( $lock + WP_CRON_LOCK_TIMEOUT > $gmt_time ) {
 668          return false;
 669      }
 670  
 671      // Sanity check.
 672      $crons = wp_get_ready_cron_jobs();
 673      if ( empty( $crons ) ) {
 674          return false;
 675      }
 676  
 677      $keys = array_keys( $crons );
 678      if ( isset( $keys[0] ) && $keys[0] > $gmt_time ) {
 679          return false;
 680      }
 681  
 682      if ( defined( 'ALTERNATE_WP_CRON' ) && ALTERNATE_WP_CRON ) {
 683          if ( 'GET' !== $_SERVER['REQUEST_METHOD'] || defined( 'DOING_AJAX' ) || defined( 'XMLRPC_REQUEST' ) ) {
 684              return false;
 685          }
 686  
 687          $doing_wp_cron = sprintf( '%.22F', $gmt_time );
 688          set_transient( 'doing_cron', $doing_wp_cron );
 689  
 690          ob_start();
 691          wp_redirect( add_query_arg( 'doing_wp_cron', $doing_wp_cron, wp_unslash( $_SERVER['REQUEST_URI'] ) ) );
 692          echo ' ';
 693  
 694          // Flush any buffers and send the headers.
 695          wp_ob_end_flush_all();
 696          flush();
 697  
 698          include_once ABSPATH . 'wp-cron.php';
 699          return true;
 700      }
 701  
 702      // Set the cron lock with the current unix timestamp, when the cron is being spawned.
 703      $doing_wp_cron = sprintf( '%.22F', $gmt_time );
 704      set_transient( 'doing_cron', $doing_wp_cron );
 705  
 706      /**
 707       * Filters the cron request arguments.
 708       *
 709       * @since 3.5.0
 710       * @since 4.5.0 The `$doing_wp_cron` parameter was added.
 711       *
 712       * @param array $cron_request_array {
 713       *     An array of cron request URL arguments.
 714       *
 715       *     @type string $url  The cron request URL.
 716       *     @type int    $key  The 22 digit GMT microtime.
 717       *     @type array  $args {
 718       *         An array of cron request arguments.
 719       *
 720       *         @type int  $timeout   The request timeout in seconds. Default .01 seconds.
 721       *         @type bool $blocking  Whether to set blocking for the request. Default false.
 722       *         @type bool $sslverify Whether SSL should be verified for the request. Default false.
 723       *     }
 724       * }
 725       * @param string $doing_wp_cron The unix timestamp of the cron lock.
 726       */
 727      $cron_request = apply_filters(
 728          'cron_request',
 729          array(
 730              'url'  => add_query_arg( 'doing_wp_cron', $doing_wp_cron, site_url( 'wp-cron.php' ) ),
 731              'key'  => $doing_wp_cron,
 732              'args' => array(
 733                  'timeout'   => 0.01,
 734                  'blocking'  => false,
 735                  /** This filter is documented in wp-includes/class-wp-http-streams.php */
 736                  'sslverify' => apply_filters( 'https_local_ssl_verify', false ),
 737              ),
 738          ),
 739          $doing_wp_cron
 740      );
 741  
 742      $result = wp_remote_post( $cron_request['url'], $cron_request['args'] );
 743      return ! is_wp_error( $result );
 744  }
 745  
 746  /**
 747   * Run scheduled callbacks or spawn cron for all scheduled events.
 748   *
 749   * Warning: This function may return Boolean FALSE, but may also return a non-Boolean
 750   * value which evaluates to FALSE. For information about casting to booleans see the
 751   * {@link https://www.php.net/manual/en/language.types.boolean.php PHP documentation}. Use
 752   * the `===` operator for testing the return value of this function.
 753   *
 754   * @since 2.1.0
 755   * @since 5.1.0 Return value added to indicate success or failure.
 756   *
 757   * @return int|false On success an integer indicating number of events spawned (0 indicates no
 758   *                   events needed to be spawned), false if spawning fails for one or more events.
 759   */
 760  function wp_cron() {
 761      // Prevent infinite loops caused by lack of wp-cron.php.
 762      if ( strpos( $_SERVER['REQUEST_URI'], '/wp-cron.php' ) !== false || ( defined( 'DISABLE_WP_CRON' ) && DISABLE_WP_CRON ) ) {
 763          return 0;
 764      }
 765  
 766      $crons = wp_get_ready_cron_jobs();
 767      if ( empty( $crons ) ) {
 768          return 0;
 769      }
 770  
 771      $gmt_time = microtime( true );
 772      $keys     = array_keys( $crons );
 773      if ( isset( $keys[0] ) && $keys[0] > $gmt_time ) {
 774          return 0;
 775      }
 776  
 777      $schedules = wp_get_schedules();
 778      $results   = array();
 779      foreach ( $crons as $timestamp => $cronhooks ) {
 780          if ( $timestamp > $gmt_time ) {
 781              break;
 782          }
 783          foreach ( (array) $cronhooks as $hook => $args ) {
 784              if ( isset( $schedules[ $hook ]['callback'] ) && ! call_user_func( $schedules[ $hook ]['callback'] ) ) {
 785                  continue;
 786              }
 787              $results[] = spawn_cron( $gmt_time );
 788              break 2;
 789          }
 790      }
 791  
 792      if ( in_array( false, $results, true ) ) {
 793          return false;
 794      }
 795      return count( $results );
 796  }
 797  
 798  /**
 799   * Retrieve supported event recurrence schedules.
 800   *
 801   * The default supported recurrences are 'hourly', 'twicedaily', 'daily', and 'weekly'.
 802   * A plugin may add more by hooking into the {@see 'cron_schedules'} filter.
 803   * The filter accepts an array of arrays. The outer array has a key that is the name
 804   * of the schedule, for example 'monthly'. The value is an array with two keys,
 805   * one is 'interval' and the other is 'display'.
 806   *
 807   * The 'interval' is a number in seconds of when the cron job should run.
 808   * So for 'hourly' the time is `HOUR_IN_SECONDS` (60 * 60 or 3600). For 'monthly',
 809   * the value would be `MONTH_IN_SECONDS` (30 * 24 * 60 * 60 or 2592000).
 810   *
 811   * The 'display' is the description. For the 'monthly' key, the 'display'
 812   * would be `__( 'Once Monthly' )`.
 813   *
 814   * For your plugin, you will be passed an array. You can easily add your
 815   * schedule by doing the following.
 816   *
 817   *     // Filter parameter variable name is 'array'.
 818   *     $array['monthly'] = array(
 819   *         'interval' => MONTH_IN_SECONDS,
 820   *         'display'  => __( 'Once Monthly' )
 821   *     );
 822   *
 823   * @since 2.1.0
 824   * @since 5.4.0 The 'weekly' schedule was added.
 825   *
 826   * @return array
 827   */
 828  function wp_get_schedules() {
 829      $schedules = array(
 830          'hourly'     => array(
 831              'interval' => HOUR_IN_SECONDS,
 832              'display'  => __( 'Once Hourly' ),
 833          ),
 834          'twicedaily' => array(
 835              'interval' => 12 * HOUR_IN_SECONDS,
 836              'display'  => __( 'Twice Daily' ),
 837          ),
 838          'daily'      => array(
 839              'interval' => DAY_IN_SECONDS,
 840              'display'  => __( 'Once Daily' ),
 841          ),
 842          'weekly'     => array(
 843              'interval' => WEEK_IN_SECONDS,
 844              'display'  => __( 'Once Weekly' ),
 845          ),
 846      );
 847  
 848      /**
 849       * Filters the non-default cron schedules.
 850       *
 851       * @since 2.1.0
 852       *
 853       * @param array $new_schedules An array of non-default cron schedules. Default empty.
 854       */
 855      return array_merge( apply_filters( 'cron_schedules', array() ), $schedules );
 856  }
 857  
 858  /**
 859   * Retrieve the recurrence schedule for an event.
 860   *
 861   * @see wp_get_schedules() for available schedules.
 862   *
 863   * @since 2.1.0
 864   * @since 5.1.0 {@see 'get_schedule'} filter added.
 865   *
 866   * @param string $hook Action hook to identify the event.
 867   * @param array  $args Optional. Arguments passed to the event's callback function.
 868   * @return string|false Schedule name on success, false if no schedule.
 869   */
 870  function wp_get_schedule( $hook, $args = array() ) {
 871      $schedule = false;
 872      $event    = wp_get_scheduled_event( $hook, $args );
 873  
 874      if ( $event ) {
 875          $schedule = $event->schedule;
 876      }
 877  
 878      /**
 879       * Filters the schedule for a hook.
 880       *
 881       * @since 5.1.0
 882       *
 883       * @param string|false $schedule Schedule for the hook. False if not found.
 884       * @param string       $hook     Action hook to execute when cron is run.
 885       * @param array        $args     Optional. Arguments to pass to the hook's callback function.
 886       */
 887      return apply_filters( 'get_schedule', $schedule, $hook, $args );
 888  }
 889  
 890  /**
 891   * Retrieve cron jobs ready to be run.
 892   *
 893   * Returns the results of _get_cron_array() limited to events ready to be run,
 894   * ie, with a timestamp in the past.
 895   *
 896   * @since 5.1.0
 897   *
 898   * @return array Cron jobs ready to be run.
 899   */
 900  function wp_get_ready_cron_jobs() {
 901      /**
 902       * Filter to preflight or hijack retrieving ready cron jobs.
 903       *
 904       * Returning an array will short-circuit the normal retrieval of ready
 905       * cron jobs, causing the function to return the filtered value instead.
 906       *
 907       * @since 5.1.0
 908       *
 909       * @param null|array $pre Array of ready cron tasks to return instead. Default null
 910       *                        to continue using results from _get_cron_array().
 911       */
 912      $pre = apply_filters( 'pre_get_ready_cron_jobs', null );
 913      if ( null !== $pre ) {
 914          return $pre;
 915      }
 916  
 917      $crons = _get_cron_array();
 918  
 919      if ( false === $crons ) {
 920          return array();
 921      }
 922  
 923      $gmt_time = microtime( true );
 924      $keys     = array_keys( $crons );
 925      if ( isset( $keys[0] ) && $keys[0] > $gmt_time ) {
 926          return array();
 927      }
 928  
 929      $results = array();
 930      foreach ( $crons as $timestamp => $cronhooks ) {
 931          if ( $timestamp > $gmt_time ) {
 932              break;
 933          }
 934          $results[ $timestamp ] = $cronhooks;
 935      }
 936  
 937      return $results;
 938  }
 939  
 940  //
 941  // Private functions.
 942  //
 943  
 944  /**
 945   * Retrieve cron info array option.
 946   *
 947   * @since 2.1.0
 948   * @access private
 949   *
 950   * @return array|false Cron info array on success, false on failure.
 951   */
 952  function _get_cron_array() {
 953      $cron = get_option( 'cron' );
 954      if ( ! is_array( $cron ) ) {
 955          return false;
 956      }
 957  
 958      if ( ! isset( $cron['version'] ) ) {
 959          $cron = _upgrade_cron_array( $cron );
 960      }
 961  
 962      unset( $cron['version'] );
 963  
 964      return $cron;
 965  }
 966  
 967  /**
 968   * Updates the CRON option with the new CRON array.
 969   *
 970   * @since 2.1.0
 971   * @since 5.1.0 Return value modified to outcome of update_option().
 972   *
 973   * @access private
 974   *
 975   * @param array $cron Cron info array from _get_cron_array().
 976   * @return bool True if cron array updated, false on failure.
 977   */
 978  function _set_cron_array( $cron ) {
 979      $cron['version'] = 2;
 980      return update_option( 'cron', $cron );
 981  }
 982  
 983  /**
 984   * Upgrade a Cron info array.
 985   *
 986   * This function upgrades the Cron info array to version 2.
 987   *
 988   * @since 2.1.0
 989   * @access private
 990   *
 991   * @param array $cron Cron info array from _get_cron_array().
 992   * @return array An upgraded Cron info array.
 993   */
 994  function _upgrade_cron_array( $cron ) {
 995      if ( isset( $cron['version'] ) && 2 == $cron['version'] ) {
 996          return $cron;
 997      }
 998  
 999      $new_cron = array();
1000  
1001      foreach ( (array) $cron as $timestamp => $hooks ) {
1002          foreach ( (array) $hooks as $hook => $args ) {
1003              $key                                     = md5( serialize( $args['args'] ) );
1004              $new_cron[ $timestamp ][ $hook ][ $key ] = $args;
1005          }
1006      }
1007  
1008      $new_cron['version'] = 2;
1009      update_option( 'cron', $new_cron );
1010      return $new_cron;
1011  }