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/wp-includes/ -> functions.php (source)

   1  <?php
   2  /**
   3   * Main WordPress API
   4   *
   5   * @package WordPress
   6   */
   7  
   8  require  ABSPATH . WPINC . '/option.php';
   9  
  10  /**
  11   * Convert given MySQL date string into a different format.
  12   *
  13   * `$format` should be a PHP date format string.
  14   * 'U' and 'G' formats will return a sum of timestamp with timezone offset.
  15   * `$date` is expected to be local time in MySQL format (`Y-m-d H:i:s`).
  16   *
  17   * Historically UTC time could be passed to the function to produce Unix timestamp.
  18   *
  19   * If `$translate` is true then the given date and format string will
  20   * be passed to `wp_date()` for translation.
  21   *
  22   * @since 0.71
  23   *
  24   * @param string $format    Format of the date to return.
  25   * @param string $date      Date string to convert.
  26   * @param bool   $translate Whether the return date should be translated. Default true.
  27   * @return string|int|false Formatted date string or sum of Unix timestamp and timezone offset.
  28   *                          False on failure.
  29   */
  30  function mysql2date( $format, $date, $translate = true ) {
  31      if ( empty( $date ) ) {
  32          return false;
  33      }
  34  
  35      $datetime = date_create( $date, wp_timezone() );
  36  
  37      if ( false === $datetime ) {
  38          return false;
  39      }
  40  
  41      // Returns a sum of timestamp with timezone offset. Ideally should never be used.
  42      if ( 'G' === $format || 'U' === $format ) {
  43          return $datetime->getTimestamp() + $datetime->getOffset();
  44      }
  45  
  46      if ( $translate ) {
  47          return wp_date( $format, $datetime->getTimestamp() );
  48      }
  49  
  50      return $datetime->format( $format );
  51  }
  52  
  53  /**
  54   * Retrieves the current time based on specified type.
  55   *
  56   * The 'mysql' type will return the time in the format for MySQL DATETIME field.
  57   * The 'timestamp' type will return the current timestamp or a sum of timestamp
  58   * and timezone offset, depending on `$gmt`.
  59   * Other strings will be interpreted as PHP date formats (e.g. 'Y-m-d').
  60   *
  61   * If $gmt is set to either '1' or 'true', then both types will use GMT time.
  62   * if $gmt is false, the output is adjusted with the GMT offset in the WordPress option.
  63   *
  64   * @since 1.0.0
  65   *
  66   * @param string   $type Type of time to retrieve. Accepts 'mysql', 'timestamp',
  67   *                       or PHP date format string (e.g. 'Y-m-d').
  68   * @param int|bool $gmt  Optional. Whether to use GMT timezone. Default false.
  69   * @return int|string Integer if $type is 'timestamp', string otherwise.
  70   */
  71  function current_time( $type, $gmt = 0 ) {
  72      // Don't use non-GMT timestamp, unless you know the difference and really need to.
  73      if ( 'timestamp' === $type || 'U' === $type ) {
  74          return $gmt ? time() : time() + (int) ( get_option( 'gmt_offset' ) * HOUR_IN_SECONDS );
  75      }
  76  
  77      if ( 'mysql' === $type ) {
  78          $type = 'Y-m-d H:i:s';
  79      }
  80  
  81      $timezone = $gmt ? new DateTimeZone( 'UTC' ) : wp_timezone();
  82      $datetime = new DateTime( 'now', $timezone );
  83  
  84      return $datetime->format( $type );
  85  }
  86  
  87  /**
  88   * Retrieves the current time as an object with the timezone from settings.
  89   *
  90   * @since 5.3.0
  91   *
  92   * @return DateTimeImmutable Date and time object.
  93   */
  94  function current_datetime() {
  95      return new DateTimeImmutable( 'now', wp_timezone() );
  96  }
  97  
  98  /**
  99   * Retrieves the timezone from site settings as a string.
 100   *
 101   * Uses the `timezone_string` option to get a proper timezone if available,
 102   * otherwise falls back to an offset.
 103   *
 104   * @since 5.3.0
 105   *
 106   * @return string PHP timezone string or a ±HH:MM offset.
 107   */
 108  function wp_timezone_string() {
 109      $timezone_string = get_option( 'timezone_string' );
 110  
 111      if ( $timezone_string ) {
 112          return $timezone_string;
 113      }
 114  
 115      $offset  = (float) get_option( 'gmt_offset' );
 116      $hours   = (int) $offset;
 117      $minutes = ( $offset - $hours );
 118  
 119      $sign      = ( $offset < 0 ) ? '-' : '+';
 120      $abs_hour  = abs( $hours );
 121      $abs_mins  = abs( $minutes * 60 );
 122      $tz_offset = sprintf( '%s%02d:%02d', $sign, $abs_hour, $abs_mins );
 123  
 124      return $tz_offset;
 125  }
 126  
 127  /**
 128   * Retrieves the timezone from site settings as a `DateTimeZone` object.
 129   *
 130   * Timezone can be based on a PHP timezone string or a ±HH:MM offset.
 131   *
 132   * @since 5.3.0
 133   *
 134   * @return DateTimeZone Timezone object.
 135   */
 136  function wp_timezone() {
 137      return new DateTimeZone( wp_timezone_string() );
 138  }
 139  
 140  /**
 141   * Retrieves the date in localized format, based on a sum of Unix timestamp and
 142   * timezone offset in seconds.
 143   *
 144   * If the locale specifies the locale month and weekday, then the locale will
 145   * take over the format for the date. If it isn't, then the date format string
 146   * will be used instead.
 147   *
 148   * Note that due to the way WP typically generates a sum of timestamp and offset
 149   * with `strtotime()`, it implies offset added at a _current_ time, not at the time
 150   * the timestamp represents. Storing such timestamps or calculating them differently
 151   * will lead to invalid output.
 152   *
 153   * @since 0.71
 154   * @since 5.3.0 Converted into a wrapper for wp_date().
 155   *
 156   * @global WP_Locale $wp_locale WordPress date and time locale object.
 157   *
 158   * @param string   $format                Format to display the date.
 159   * @param int|bool $timestamp_with_offset Optional. A sum of Unix timestamp and timezone offset
 160   *                                        in seconds. Default false.
 161   * @param bool     $gmt                   Optional. Whether to use GMT timezone. Only applies
 162   *                                        if timestamp is not provided. Default false.
 163   * @return string The date, translated if locale specifies it.
 164   */
 165  function date_i18n( $format, $timestamp_with_offset = false, $gmt = false ) {
 166      $timestamp = $timestamp_with_offset;
 167  
 168      // If timestamp is omitted it should be current time (summed with offset, unless `$gmt` is true).
 169      if ( ! is_numeric( $timestamp ) ) {
 170          $timestamp = current_time( 'timestamp', $gmt );
 171      }
 172  
 173      /*
 174       * This is a legacy implementation quirk that the returned timestamp is also with offset.
 175       * Ideally this function should never be used to produce a timestamp.
 176       */
 177      if ( 'U' === $format ) {
 178          $date = $timestamp;
 179      } elseif ( $gmt && false === $timestamp_with_offset ) { // Current time in UTC.
 180          $date = wp_date( $format, null, new DateTimeZone( 'UTC' ) );
 181      } elseif ( false === $timestamp_with_offset ) { // Current time in site's timezone.
 182          $date = wp_date( $format );
 183      } else {
 184          /*
 185           * Timestamp with offset is typically produced by a UTC `strtotime()` call on an input without timezone.
 186           * This is the best attempt to reverse that operation into a local time to use.
 187           */
 188          $local_time = gmdate( 'Y-m-d H:i:s', $timestamp );
 189          $timezone   = wp_timezone();
 190          $datetime   = date_create( $local_time, $timezone );
 191          $date       = wp_date( $format, $datetime->getTimestamp(), $timezone );
 192      }
 193  
 194      /**
 195       * Filters the date formatted based on the locale.
 196       *
 197       * @since 2.8.0
 198       *
 199       * @param string $date      Formatted date string.
 200       * @param string $format    Format to display the date.
 201       * @param int    $timestamp A sum of Unix timestamp and timezone offset in seconds.
 202       *                          Might be without offset if input omitted timestamp but requested GMT.
 203       * @param bool   $gmt       Whether to use GMT timezone. Only applies if timestamp was not provided.
 204       *                          Default false.
 205       */
 206      $date = apply_filters( 'date_i18n', $date, $format, $timestamp, $gmt );
 207  
 208      return $date;
 209  }
 210  
 211  /**
 212   * Retrieves the date, in localized format.
 213   *
 214   * This is a newer function, intended to replace `date_i18n()` without legacy quirks in it.
 215   *
 216   * Note that, unlike `date_i18n()`, this function accepts a true Unix timestamp, not summed
 217   * with timezone offset.
 218   *
 219   * @since 5.3.0
 220   *
 221   * @param string       $format    PHP date format.
 222   * @param int          $timestamp Optional. Unix timestamp. Defaults to current time.
 223   * @param DateTimeZone $timezone  Optional. Timezone to output result in. Defaults to timezone
 224   *                                from site settings.
 225   * @return string|false The date, translated if locale specifies it. False on invalid timestamp input.
 226   */
 227  function wp_date( $format, $timestamp = null, $timezone = null ) {
 228      global $wp_locale;
 229  
 230      if ( null === $timestamp ) {
 231          $timestamp = time();
 232      } elseif ( ! is_numeric( $timestamp ) ) {
 233          return false;
 234      }
 235  
 236      if ( ! $timezone ) {
 237          $timezone = wp_timezone();
 238      }
 239  
 240      $datetime = date_create( '@' . $timestamp );
 241      $datetime->setTimezone( $timezone );
 242  
 243      if ( empty( $wp_locale->month ) || empty( $wp_locale->weekday ) ) {
 244          $date = $datetime->format( $format );
 245      } else {
 246          // We need to unpack shorthand `r` format because it has parts that might be localized.
 247          $format = preg_replace( '/(?<!\\\\)r/', DATE_RFC2822, $format );
 248  
 249          $new_format    = '';
 250          $format_length = strlen( $format );
 251          $month         = $wp_locale->get_month( $datetime->format( 'm' ) );
 252          $weekday       = $wp_locale->get_weekday( $datetime->format( 'w' ) );
 253  
 254          for ( $i = 0; $i < $format_length; $i ++ ) {
 255              switch ( $format[ $i ] ) {
 256                  case 'D':
 257                      $new_format .= addcslashes( $wp_locale->get_weekday_abbrev( $weekday ), '\\A..Za..z' );
 258                      break;
 259                  case 'F':
 260                      $new_format .= addcslashes( $month, '\\A..Za..z' );
 261                      break;
 262                  case 'l':
 263                      $new_format .= addcslashes( $weekday, '\\A..Za..z' );
 264                      break;
 265                  case 'M':
 266                      $new_format .= addcslashes( $wp_locale->get_month_abbrev( $month ), '\\A..Za..z' );
 267                      break;
 268                  case 'a':
 269                      $new_format .= addcslashes( $wp_locale->get_meridiem( $datetime->format( 'a' ) ), '\\A..Za..z' );
 270                      break;
 271                  case 'A':
 272                      $new_format .= addcslashes( $wp_locale->get_meridiem( $datetime->format( 'A' ) ), '\\A..Za..z' );
 273                      break;
 274                  case '\\':
 275                      $new_format .= $format[ $i ];
 276  
 277                      // If character follows a slash, we add it without translating.
 278                      if ( $i < $format_length ) {
 279                          $new_format .= $format[ ++$i ];
 280                      }
 281                      break;
 282                  default:
 283                      $new_format .= $format[ $i ];
 284                      break;
 285              }
 286          }
 287  
 288          $date = $datetime->format( $new_format );
 289          $date = wp_maybe_decline_date( $date, $format );
 290      }
 291  
 292      /**
 293       * Filters the date formatted based on the locale.
 294       *
 295       * @since 5.3.0
 296       *
 297       * @param string       $date      Formatted date string.
 298       * @param string       $format    Format to display the date.
 299       * @param int          $timestamp Unix timestamp.
 300       * @param DateTimeZone $timezone  Timezone.
 301       */
 302      $date = apply_filters( 'wp_date', $date, $format, $timestamp, $timezone );
 303  
 304      return $date;
 305  }
 306  
 307  /**
 308   * Determines if the date should be declined.
 309   *
 310   * If the locale specifies that month names require a genitive case in certain
 311   * formats (like 'j F Y'), the month name will be replaced with a correct form.
 312   *
 313   * @since 4.4.0
 314   * @since 5.4.0 The `$format` parameter was added.
 315   *
 316   * @global WP_Locale $wp_locale WordPress date and time locale object.
 317   *
 318   * @param string $date   Formatted date string.
 319   * @param string $format Optional. Date format to check. Default empty string.
 320   * @return string The date, declined if locale specifies it.
 321   */
 322  function wp_maybe_decline_date( $date, $format = '' ) {
 323      global $wp_locale;
 324  
 325      // i18n functions are not available in SHORTINIT mode.
 326      if ( ! function_exists( '_x' ) ) {
 327          return $date;
 328      }
 329  
 330      /*
 331       * translators: If months in your language require a genitive case,
 332       * translate this to 'on'. Do not translate into your own language.
 333       */
 334      if ( 'on' === _x( 'off', 'decline months names: on or off' ) ) {
 335  
 336          $months          = $wp_locale->month;
 337          $months_genitive = $wp_locale->month_genitive;
 338  
 339          /*
 340           * Match a format like 'j F Y' or 'j. F' (day of the month, followed by month name)
 341           * and decline the month.
 342           */
 343          if ( $format ) {
 344              $decline = preg_match( '#[dj]\.? F#', $format );
 345          } else {
 346              // If the format is not passed, try to guess it from the date string.
 347              $decline = preg_match( '#\b\d{1,2}\.? [^\d ]+\b#u', $date );
 348          }
 349  
 350          if ( $decline ) {
 351              foreach ( $months as $key => $month ) {
 352                  $months[ $key ] = '# ' . preg_quote( $month, '#' ) . '\b#u';
 353              }
 354  
 355              foreach ( $months_genitive as $key => $month ) {
 356                  $months_genitive[ $key ] = ' ' . $month;
 357              }
 358  
 359              $date = preg_replace( $months, $months_genitive, $date );
 360          }
 361  
 362          /*
 363           * Match a format like 'F jS' or 'F j' (month name, followed by day with an optional ordinal suffix)
 364           * and change it to declined 'j F'.
 365           */
 366          if ( $format ) {
 367              $decline = preg_match( '#F [dj]#', $format );
 368          } else {
 369              // If the format is not passed, try to guess it from the date string.
 370              $decline = preg_match( '#\b[^\d ]+ \d{1,2}(st|nd|rd|th)?\b#u', trim( $date ) );
 371          }
 372  
 373          if ( $decline ) {
 374              foreach ( $months as $key => $month ) {
 375                  $months[ $key ] = '#\b' . preg_quote( $month, '#' ) . ' (\d{1,2})(st|nd|rd|th)?([-–]\d{1,2})?(st|nd|rd|th)?\b#u';
 376              }
 377  
 378              foreach ( $months_genitive as $key => $month ) {
 379                  $months_genitive[ $key ] = '$1$3 ' . $month;
 380              }
 381  
 382              $date = preg_replace( $months, $months_genitive, $date );
 383          }
 384      }
 385  
 386      // Used for locale-specific rules.
 387      $locale = get_locale();
 388  
 389      if ( 'ca' === $locale ) {
 390          // " de abril| de agost| de octubre..." -> " d'abril| d'agost| d'octubre..."
 391          $date = preg_replace( '# de ([ao])#i', " d'\\1", $date );
 392      }
 393  
 394      return $date;
 395  }
 396  
 397  /**
 398   * Convert float number to format based on the locale.
 399   *
 400   * @since 2.3.0
 401   *
 402   * @global WP_Locale $wp_locale WordPress date and time locale object.
 403   *
 404   * @param float $number   The number to convert based on locale.
 405   * @param int   $decimals Optional. Precision of the number of decimal places. Default 0.
 406   * @return string Converted number in string format.
 407   */
 408  function number_format_i18n( $number, $decimals = 0 ) {
 409      global $wp_locale;
 410  
 411      if ( isset( $wp_locale ) ) {
 412          $formatted = number_format( $number, absint( $decimals ), $wp_locale->number_format['decimal_point'], $wp_locale->number_format['thousands_sep'] );
 413      } else {
 414          $formatted = number_format( $number, absint( $decimals ) );
 415      }
 416  
 417      /**
 418       * Filters the number formatted based on the locale.
 419       *
 420       * @since 2.8.0
 421       * @since 4.9.0 The `$number` and `$decimals` parameters were added.
 422       *
 423       * @param string $formatted Converted number in string format.
 424       * @param float  $number    The number to convert based on locale.
 425       * @param int    $decimals  Precision of the number of decimal places.
 426       */
 427      return apply_filters( 'number_format_i18n', $formatted, $number, $decimals );
 428  }
 429  
 430  /**
 431   * Convert number of bytes largest unit bytes will fit into.
 432   *
 433   * It is easier to read 1 KB than 1024 bytes and 1 MB than 1048576 bytes. Converts
 434   * number of bytes to human readable number by taking the number of that unit
 435   * that the bytes will go into it. Supports TB value.
 436   *
 437   * Please note that integers in PHP are limited to 32 bits, unless they are on
 438   * 64 bit architecture, then they have 64 bit size. If you need to place the
 439   * larger size then what PHP integer type will hold, then use a string. It will
 440   * be converted to a double, which should always have 64 bit length.
 441   *
 442   * Technically the correct unit names for powers of 1024 are KiB, MiB etc.
 443   *
 444   * @since 2.3.0
 445   *
 446   * @param int|string $bytes    Number of bytes. Note max integer size for integers.
 447   * @param int        $decimals Optional. Precision of number of decimal places. Default 0.
 448   * @return string|false Number string on success, false on failure.
 449   */
 450  function size_format( $bytes, $decimals = 0 ) {
 451      $quant = array(
 452          /* translators: Unit symbol for terabyte. */
 453          _x( 'TB', 'unit symbol' ) => TB_IN_BYTES,
 454          /* translators: Unit symbol for gigabyte. */
 455          _x( 'GB', 'unit symbol' ) => GB_IN_BYTES,
 456          /* translators: Unit symbol for megabyte. */
 457          _x( 'MB', 'unit symbol' ) => MB_IN_BYTES,
 458          /* translators: Unit symbol for kilobyte. */
 459          _x( 'KB', 'unit symbol' ) => KB_IN_BYTES,
 460          /* translators: Unit symbol for byte. */
 461          _x( 'B', 'unit symbol' )  => 1,
 462      );
 463  
 464      if ( 0 === $bytes ) {
 465          /* translators: Unit symbol for byte. */
 466          return number_format_i18n( 0, $decimals ) . ' ' . _x( 'B', 'unit symbol' );
 467      }
 468  
 469      foreach ( $quant as $unit => $mag ) {
 470          if ( doubleval( $bytes ) >= $mag ) {
 471              return number_format_i18n( $bytes / $mag, $decimals ) . ' ' . $unit;
 472          }
 473      }
 474  
 475      return false;
 476  }
 477  
 478  /**
 479   * Convert a duration to human readable format.
 480   *
 481   * @since 5.1.0
 482   *
 483   * @param string $duration Duration will be in string format (HH:ii:ss) OR (ii:ss),
 484   *                         with a possible prepended negative sign (-).
 485   * @return string|false A human readable duration string, false on failure.
 486   */
 487  function human_readable_duration( $duration = '' ) {
 488      if ( ( empty( $duration ) || ! is_string( $duration ) ) ) {
 489          return false;
 490      }
 491  
 492      $duration = trim( $duration );
 493  
 494      // Remove prepended negative sign.
 495      if ( '-' === substr( $duration, 0, 1 ) ) {
 496          $duration = substr( $duration, 1 );
 497      }
 498  
 499      // Extract duration parts.
 500      $duration_parts = array_reverse( explode( ':', $duration ) );
 501      $duration_count = count( $duration_parts );
 502  
 503      $hour   = null;
 504      $minute = null;
 505      $second = null;
 506  
 507      if ( 3 === $duration_count ) {
 508          // Validate HH:ii:ss duration format.
 509          if ( ! ( (bool) preg_match( '/^([0-9]+):([0-5]?[0-9]):([0-5]?[0-9])$/', $duration ) ) ) {
 510              return false;
 511          }
 512          // Three parts: hours, minutes & seconds.
 513          list( $second, $minute, $hour ) = $duration_parts;
 514      } elseif ( 2 === $duration_count ) {
 515          // Validate ii:ss duration format.
 516          if ( ! ( (bool) preg_match( '/^([0-5]?[0-9]):([0-5]?[0-9])$/', $duration ) ) ) {
 517              return false;
 518          }
 519          // Two parts: minutes & seconds.
 520          list( $second, $minute ) = $duration_parts;
 521      } else {
 522          return false;
 523      }
 524  
 525      $human_readable_duration = array();
 526  
 527      // Add the hour part to the string.
 528      if ( is_numeric( $hour ) ) {
 529          /* translators: %s: Time duration in hour or hours. */
 530          $human_readable_duration[] = sprintf( _n( '%s hour', '%s hours', $hour ), (int) $hour );
 531      }
 532  
 533      // Add the minute part to the string.
 534      if ( is_numeric( $minute ) ) {
 535          /* translators: %s: Time duration in minute or minutes. */
 536          $human_readable_duration[] = sprintf( _n( '%s minute', '%s minutes', $minute ), (int) $minute );
 537      }
 538  
 539      // Add the second part to the string.
 540      if ( is_numeric( $second ) ) {
 541          /* translators: %s: Time duration in second or seconds. */
 542          $human_readable_duration[] = sprintf( _n( '%s second', '%s seconds', $second ), (int) $second );
 543      }
 544  
 545      return implode( ', ', $human_readable_duration );
 546  }
 547  
 548  /**
 549   * Get the week start and end from the datetime or date string from MySQL.
 550   *
 551   * @since 0.71
 552   *
 553   * @param string     $mysqlstring   Date or datetime field type from MySQL.
 554   * @param int|string $start_of_week Optional. Start of the week as an integer. Default empty string.
 555   * @return array Keys are 'start' and 'end'.
 556   */
 557  function get_weekstartend( $mysqlstring, $start_of_week = '' ) {
 558      // MySQL string year.
 559      $my = substr( $mysqlstring, 0, 4 );
 560  
 561      // MySQL string month.
 562      $mm = substr( $mysqlstring, 8, 2 );
 563  
 564      // MySQL string day.
 565      $md = substr( $mysqlstring, 5, 2 );
 566  
 567      // The timestamp for MySQL string day.
 568      $day = mktime( 0, 0, 0, $md, $mm, $my );
 569  
 570      // The day of the week from the timestamp.
 571      $weekday = gmdate( 'w', $day );
 572  
 573      if ( ! is_numeric( $start_of_week ) ) {
 574          $start_of_week = get_option( 'start_of_week' );
 575      }
 576  
 577      if ( $weekday < $start_of_week ) {
 578          $weekday += 7;
 579      }
 580  
 581      // The most recent week start day on or before $day.
 582      $start = $day - DAY_IN_SECONDS * ( $weekday - $start_of_week );
 583  
 584      // $start + 1 week - 1 second.
 585      $end = $start + WEEK_IN_SECONDS - 1;
 586      return compact( 'start', 'end' );
 587  }
 588  
 589  /**
 590   * Serialize data, if needed.
 591   *
 592   * @since 2.0.5
 593   *
 594   * @param string|array|object $data Data that might be serialized.
 595   * @return mixed A scalar data.
 596   */
 597  function maybe_serialize( $data ) {
 598      if ( is_array( $data ) || is_object( $data ) ) {
 599          return serialize( $data );
 600      }
 601  
 602      /*
 603       * Double serialization is required for backward compatibility.
 604       * See https://core.trac.wordpress.org/ticket/12930
 605       * Also the world will end. See WP 3.6.1.
 606       */
 607      if ( is_serialized( $data, false ) ) {
 608          return serialize( $data );
 609      }
 610  
 611      return $data;
 612  }
 613  
 614  /**
 615   * Unserialize data only if it was serialized.
 616   *
 617   * @since 2.0.0
 618   *
 619   * @param string $data Data that might be unserialized.
 620   * @return mixed Unserialized data can be any type.
 621   */
 622  function maybe_unserialize( $data ) {
 623      if ( is_serialized( $data ) ) { // Don't attempt to unserialize data that wasn't serialized going in.
 624          return @unserialize( trim( $data ) );
 625      }
 626  
 627      return $data;
 628  }
 629  
 630  /**
 631   * Check value to find if it was serialized.
 632   *
 633   * If $data is not an string, then returned value will always be false.
 634   * Serialized data is always a string.
 635   *
 636   * @since 2.0.5
 637   *
 638   * @param string $data   Value to check to see if was serialized.
 639   * @param bool   $strict Optional. Whether to be strict about the end of the string. Default true.
 640   * @return bool False if not serialized and true if it was.
 641   */
 642  function is_serialized( $data, $strict = true ) {
 643      // If it isn't a string, it isn't serialized.
 644      if ( ! is_string( $data ) ) {
 645          return false;
 646      }
 647      $data = trim( $data );
 648      if ( 'N;' === $data ) {
 649          return true;
 650      }
 651      if ( strlen( $data ) < 4 ) {
 652          return false;
 653      }
 654      if ( ':' !== $data[1] ) {
 655          return false;
 656      }
 657      if ( $strict ) {
 658          $lastc = substr( $data, -1 );
 659          if ( ';' !== $lastc && '}' !== $lastc ) {
 660              return false;
 661          }
 662      } else {
 663          $semicolon = strpos( $data, ';' );
 664          $brace     = strpos( $data, '}' );
 665          // Either ; or } must exist.
 666          if ( false === $semicolon && false === $brace ) {
 667              return false;
 668          }
 669          // But neither must be in the first X characters.
 670          if ( false !== $semicolon && $semicolon < 3 ) {
 671              return false;
 672          }
 673          if ( false !== $brace && $brace < 4 ) {
 674              return false;
 675          }
 676      }
 677      $token = $data[0];
 678      switch ( $token ) {
 679          case 's':
 680              if ( $strict ) {
 681                  if ( '"' !== substr( $data, -2, 1 ) ) {
 682                      return false;
 683                  }
 684              } elseif ( false === strpos( $data, '"' ) ) {
 685                  return false;
 686              }
 687              // Or else fall through.
 688          case 'a':
 689          case 'O':
 690              return (bool) preg_match( "/^{$token}:[0-9]+:/s", $data );
 691          case 'b':
 692          case 'i':
 693          case 'd':
 694              $end = $strict ? '$' : '';
 695              return (bool) preg_match( "/^{$token}:[0-9.E+-]+;$end/", $data );
 696      }
 697      return false;
 698  }
 699  
 700  /**
 701   * Check whether serialized data is of string type.
 702   *
 703   * @since 2.0.5
 704   *
 705   * @param string $data Serialized data.
 706   * @return bool False if not a serialized string, true if it is.
 707   */
 708  function is_serialized_string( $data ) {
 709      // if it isn't a string, it isn't a serialized string.
 710      if ( ! is_string( $data ) ) {
 711          return false;
 712      }
 713      $data = trim( $data );
 714      if ( strlen( $data ) < 4 ) {
 715          return false;
 716      } elseif ( ':' !== $data[1] ) {
 717          return false;
 718      } elseif ( ';' !== substr( $data, -1 ) ) {
 719          return false;
 720      } elseif ( 's' !== $data[0] ) {
 721          return false;
 722      } elseif ( '"' !== substr( $data, -2, 1 ) ) {
 723          return false;
 724      } else {
 725          return true;
 726      }
 727  }
 728  
 729  /**
 730   * Retrieve post title from XMLRPC XML.
 731   *
 732   * If the title element is not part of the XML, then the default post title from
 733   * the $post_default_title will be used instead.
 734   *
 735   * @since 0.71
 736   *
 737   * @global string $post_default_title Default XML-RPC post title.
 738   *
 739   * @param string $content XMLRPC XML Request content
 740   * @return string Post title
 741   */
 742  function xmlrpc_getposttitle( $content ) {
 743      global $post_default_title;
 744      if ( preg_match( '/<title>(.+?)<\/title>/is', $content, $matchtitle ) ) {
 745          $post_title = $matchtitle[1];
 746      } else {
 747          $post_title = $post_default_title;
 748      }
 749      return $post_title;
 750  }
 751  
 752  /**
 753   * Retrieve the post category or categories from XMLRPC XML.
 754   *
 755   * If the category element is not found, then the default post category will be
 756   * used. The return type then would be what $post_default_category. If the
 757   * category is found, then it will always be an array.
 758   *
 759   * @since 0.71
 760   *
 761   * @global string $post_default_category Default XML-RPC post category.
 762   *
 763   * @param string $content XMLRPC XML Request content
 764   * @return string|array List of categories or category name.
 765   */
 766  function xmlrpc_getpostcategory( $content ) {
 767      global $post_default_category;
 768      if ( preg_match( '/<category>(.+?)<\/category>/is', $content, $matchcat ) ) {
 769          $post_category = trim( $matchcat[1], ',' );
 770          $post_category = explode( ',', $post_category );
 771      } else {
 772          $post_category = $post_default_category;
 773      }
 774      return $post_category;
 775  }
 776  
 777  /**
 778   * XMLRPC XML content without title and category elements.
 779   *
 780   * @since 0.71
 781   *
 782   * @param string $content XML-RPC XML Request content.
 783   * @return string XMLRPC XML Request content without title and category elements.
 784   */
 785  function xmlrpc_removepostdata( $content ) {
 786      $content = preg_replace( '/<title>(.+?)<\/title>/si', '', $content );
 787      $content = preg_replace( '/<category>(.+?)<\/category>/si', '', $content );
 788      $content = trim( $content );
 789      return $content;
 790  }
 791  
 792  /**
 793   * Use RegEx to extract URLs from arbitrary content.
 794   *
 795   * @since 3.7.0
 796   *
 797   * @param string $content Content to extract URLs from.
 798   * @return string[] Array of URLs found in passed string.
 799   */
 800  function wp_extract_urls( $content ) {
 801      preg_match_all(
 802          "#([\"']?)("
 803              . '(?:([\w-]+:)?//?)'
 804              . '[^\s()<>]+'
 805              . '[.]'
 806              . '(?:'
 807                  . '\([\w\d]+\)|'
 808                  . '(?:'
 809                      . "[^`!()\[\]{};:'\".,<>«»“”‘’\s]|"
 810                      . '(?:[:]\d+)?/?'
 811                  . ')+'
 812              . ')'
 813          . ")\\1#",
 814          $content,
 815          $post_links
 816      );
 817  
 818      $post_links = array_unique( array_map( 'html_entity_decode', $post_links[2] ) );
 819  
 820      return array_values( $post_links );
 821  }
 822  
 823  /**
 824   * Check content for video and audio links to add as enclosures.
 825   *
 826   * Will not add enclosures that have already been added and will
 827   * remove enclosures that are no longer in the post. This is called as
 828   * pingbacks and trackbacks.
 829   *
 830   * @since 1.5.0
 831   * @since 5.3.0 The `$content` parameter was made optional, and the `$post` parameter was
 832   *              updated to accept a post ID or a WP_Post object.
 833   * @since 5.6.0 The `$content` parameter is no longer optional, but passing `null` to skip it
 834   *              is still supported.
 835   *
 836   * @global wpdb $wpdb WordPress database abstraction object.
 837   *
 838   * @param string|null $content Post content. If `null`, the `post_content` field from `$post` is used.
 839   * @param int|WP_Post $post    Post ID or post object.
 840   * @return null|bool Returns false if post is not found.
 841   */
 842  function do_enclose( $content, $post ) {
 843      global $wpdb;
 844  
 845      // @todo Tidy this code and make the debug code optional.
 846      include_once  ABSPATH . WPINC . '/class-IXR.php';
 847  
 848      $post = get_post( $post );
 849      if ( ! $post ) {
 850          return false;
 851      }
 852  
 853      if ( null === $content ) {
 854          $content = $post->post_content;
 855      }
 856  
 857      $post_links = array();
 858  
 859      $pung = get_enclosed( $post->ID );
 860  
 861      $post_links_temp = wp_extract_urls( $content );
 862  
 863      foreach ( $pung as $link_test ) {
 864          // Link is no longer in post.
 865          if ( ! in_array( $link_test, $post_links_temp, true ) ) {
 866              $mids = $wpdb->get_col( $wpdb->prepare( "SELECT meta_id FROM $wpdb->postmeta WHERE post_id = %d AND meta_key = 'enclosure' AND meta_value LIKE %s", $post->ID, $wpdb->esc_like( $link_test ) . '%' ) );
 867              foreach ( $mids as $mid ) {
 868                  delete_metadata_by_mid( 'post', $mid );
 869              }
 870          }
 871      }
 872  
 873      foreach ( (array) $post_links_temp as $link_test ) {
 874          // If we haven't pung it already.
 875          if ( ! in_array( $link_test, $pung, true ) ) {
 876              $test = parse_url( $link_test );
 877              if ( false === $test ) {
 878                  continue;
 879              }
 880              if ( isset( $test['query'] ) ) {
 881                  $post_links[] = $link_test;
 882              } elseif ( isset( $test['path'] ) && ( '/' !== $test['path'] ) && ( '' !== $test['path'] ) ) {
 883                  $post_links[] = $link_test;
 884              }
 885          }
 886      }
 887  
 888      /**
 889       * Filters the list of enclosure links before querying the database.
 890       *
 891       * Allows for the addition and/or removal of potential enclosures to save
 892       * to postmeta before checking the database for existing enclosures.
 893       *
 894       * @since 4.4.0
 895       *
 896       * @param string[] $post_links An array of enclosure links.
 897       * @param int      $post_ID    Post ID.
 898       */
 899      $post_links = apply_filters( 'enclosure_links', $post_links, $post->ID );
 900  
 901      foreach ( (array) $post_links as $url ) {
 902          if ( '' !== $url && ! $wpdb->get_var( $wpdb->prepare( "SELECT post_id FROM $wpdb->postmeta WHERE post_id = %d AND meta_key = 'enclosure' AND meta_value LIKE %s", $post->ID, $wpdb->esc_like( $url ) . '%' ) ) ) {
 903  
 904              $headers = wp_get_http_headers( $url );
 905              if ( $headers ) {
 906                  $len           = isset( $headers['content-length'] ) ? (int) $headers['content-length'] : 0;
 907                  $type          = isset( $headers['content-type'] ) ? $headers['content-type'] : '';
 908                  $allowed_types = array( 'video', 'audio' );
 909  
 910                  // Check to see if we can figure out the mime type from the extension.
 911                  $url_parts = parse_url( $url );
 912                  if ( false !== $url_parts && ! empty( $url_parts['path'] ) ) {
 913                      $extension = pathinfo( $url_parts['path'], PATHINFO_EXTENSION );
 914                      if ( ! empty( $extension ) ) {
 915                          foreach ( wp_get_mime_types() as $exts => $mime ) {
 916                              if ( preg_match( '!^(' . $exts . ')$!i', $extension ) ) {
 917                                  $type = $mime;
 918                                  break;
 919                              }
 920                          }
 921                      }
 922                  }
 923  
 924                  if ( in_array( substr( $type, 0, strpos( $type, '/' ) ), $allowed_types, true ) ) {
 925                      add_post_meta( $post->ID, 'enclosure', "$url\n$len\n$mime\n" );
 926                  }
 927              }
 928          }
 929      }
 930  }
 931  
 932  /**
 933   * Retrieve HTTP Headers from URL.
 934   *
 935   * @since 1.5.1
 936   *
 937   * @param string $url        URL to retrieve HTTP headers from.
 938   * @param bool   $deprecated Not Used.
 939   * @return bool|string False on failure, headers on success.
 940   */
 941  function wp_get_http_headers( $url, $deprecated = false ) {
 942      if ( ! empty( $deprecated ) ) {
 943          _deprecated_argument( __FUNCTION__, '2.7.0' );
 944      }
 945  
 946      $response = wp_safe_remote_head( $url );
 947  
 948      if ( is_wp_error( $response ) ) {
 949          return false;
 950      }
 951  
 952      return wp_remote_retrieve_headers( $response );
 953  }
 954  
 955  /**
 956   * Determines whether the publish date of the current post in the loop is different
 957   * from the publish date of the previous post in the loop.
 958   *
 959   * For more information on this and similar theme functions, check out
 960   * the {@link https://developer.wordpress.org/themes/basics/conditional-tags/
 961   * Conditional Tags} article in the Theme Developer Handbook.
 962   *
 963   * @since 0.71
 964   *
 965   * @global string $currentday  The day of the current post in the loop.
 966   * @global string $previousday The day of the previous post in the loop.
 967   *
 968   * @return int 1 when new day, 0 if not a new day.
 969   */
 970  function is_new_day() {
 971      global $currentday, $previousday;
 972  
 973      if ( $currentday !== $previousday ) {
 974          return 1;
 975      } else {
 976          return 0;
 977      }
 978  }
 979  
 980  /**
 981   * Build URL query based on an associative and, or indexed array.
 982   *
 983   * This is a convenient function for easily building url queries. It sets the
 984   * separator to '&' and uses _http_build_query() function.
 985   *
 986   * @since 2.3.0
 987   *
 988   * @see _http_build_query() Used to build the query
 989   * @link https://www.php.net/manual/en/function.http-build-query.php for more on what
 990   *       http_build_query() does.
 991   *
 992   * @param array $data URL-encode key/value pairs.
 993   * @return string URL-encoded string.
 994   */
 995  function build_query( $data ) {
 996      return _http_build_query( $data, null, '&', '', false );
 997  }
 998  
 999  /**
1000   * From php.net (modified by Mark Jaquith to behave like the native PHP5 function).
1001   *
1002   * @since 3.2.0
1003   * @access private
1004   *
1005   * @see https://www.php.net/manual/en/function.http-build-query.php
1006   *
1007   * @param array|object $data      An array or object of data. Converted to array.
1008   * @param string       $prefix    Optional. Numeric index. If set, start parameter numbering with it.
1009   *                                Default null.
1010   * @param string       $sep       Optional. Argument separator; defaults to 'arg_separator.output'.
1011   *                                Default null.
1012   * @param string       $key       Optional. Used to prefix key name. Default empty.
1013   * @param bool         $urlencode Optional. Whether to use urlencode() in the result. Default true.
1014   * @return string The query string.
1015   */
1016  function _http_build_query( $data, $prefix = null, $sep = null, $key = '', $urlencode = true ) {
1017      $ret = array();
1018  
1019      foreach ( (array) $data as $k => $v ) {
1020          if ( $urlencode ) {
1021              $k = urlencode( $k );
1022          }
1023          if ( is_int( $k ) && null != $prefix ) {
1024              $k = $prefix . $k;
1025          }
1026          if ( ! empty( $key ) ) {
1027              $k = $key . '%5B' . $k . '%5D';
1028          }
1029          if ( null === $v ) {
1030              continue;
1031          } elseif ( false === $v ) {
1032              $v = '0';
1033          }
1034  
1035          if ( is_array( $v ) || is_object( $v ) ) {
1036              array_push( $ret, _http_build_query( $v, '', $sep, $k, $urlencode ) );
1037          } elseif ( $urlencode ) {
1038              array_push( $ret, $k . '=' . urlencode( $v ) );
1039          } else {
1040              array_push( $ret, $k . '=' . $v );
1041          }
1042      }
1043  
1044      if ( null === $sep ) {
1045          $sep = ini_get( 'arg_separator.output' );
1046      }
1047  
1048      return implode( $sep, $ret );
1049  }
1050  
1051  /**
1052   * Retrieves a modified URL query string.
1053   *
1054   * You can rebuild the URL and append query variables to the URL query by using this function.
1055   * There are two ways to use this function; either a single key and value, or an associative array.
1056   *
1057   * Using a single key and value:
1058   *
1059   *     add_query_arg( 'key', 'value', 'http://example.com' );
1060   *
1061   * Using an associative array:
1062   *
1063   *     add_query_arg( array(
1064   *         'key1' => 'value1',
1065   *         'key2' => 'value2',
1066   *     ), 'http://example.com' );
1067   *
1068   * Omitting the URL from either use results in the current URL being used
1069   * (the value of `$_SERVER['REQUEST_URI']`).
1070   *
1071   * Values are expected to be encoded appropriately with urlencode() or rawurlencode().
1072   *
1073   * Setting any query variable's value to boolean false removes the key (see remove_query_arg()).
1074   *
1075   * Important: The return value of add_query_arg() is not escaped by default. Output should be
1076   * late-escaped with esc_url() or similar to help prevent vulnerability to cross-site scripting
1077   * (XSS) attacks.
1078   *
1079   * @since 1.5.0
1080   * @since 5.3.0 Formalized the existing and already documented parameters
1081   *              by adding `...$args` to the function signature.
1082   *
1083   * @param string|array $key   Either a query variable key, or an associative array of query variables.
1084   * @param string       $value Optional. Either a query variable value, or a URL to act upon.
1085   * @param string       $url   Optional. A URL to act upon.
1086   * @return string New URL query string (unescaped).
1087   */
1088  function add_query_arg( ...$args ) {
1089      if ( is_array( $args[0] ) ) {
1090          if ( count( $args ) < 2 || false === $args[1] ) {
1091              $uri = $_SERVER['REQUEST_URI'];
1092          } else {
1093              $uri = $args[1];
1094          }
1095      } else {
1096          if ( count( $args ) < 3 || false === $args[2] ) {
1097              $uri = $_SERVER['REQUEST_URI'];
1098          } else {
1099              $uri = $args[2];
1100          }
1101      }
1102  
1103      $frag = strstr( $uri, '#' );
1104      if ( $frag ) {
1105          $uri = substr( $uri, 0, -strlen( $frag ) );
1106      } else {
1107          $frag = '';
1108      }
1109  
1110      if ( 0 === stripos( $uri, 'http://' ) ) {
1111          $protocol = 'http://';
1112          $uri      = substr( $uri, 7 );
1113      } elseif ( 0 === stripos( $uri, 'https://' ) ) {
1114          $protocol = 'https://';
1115          $uri      = substr( $uri, 8 );
1116      } else {
1117          $protocol = '';
1118      }
1119  
1120      if ( strpos( $uri, '?' ) !== false ) {
1121          list( $base, $query ) = explode( '?', $uri, 2 );
1122          $base                .= '?';
1123      } elseif ( $protocol || strpos( $uri, '=' ) === false ) {
1124          $base  = $uri . '?';
1125          $query = '';
1126      } else {
1127          $base  = '';
1128          $query = $uri;
1129      }
1130  
1131      wp_parse_str( $query, $qs );
1132      $qs = urlencode_deep( $qs ); // This re-URL-encodes things that were already in the query string.
1133      if ( is_array( $args[0] ) ) {
1134          foreach ( $args[0] as $k => $v ) {
1135              $qs[ $k ] = $v;
1136          }
1137      } else {
1138          $qs[ $args[0] ] = $args[1];
1139      }
1140  
1141      foreach ( $qs as $k => $v ) {
1142          if ( false === $v ) {
1143              unset( $qs[ $k ] );
1144          }
1145      }
1146  
1147      $ret = build_query( $qs );
1148      $ret = trim( $ret, '?' );
1149      $ret = preg_replace( '#=(&|$)#', '$1', $ret );
1150      $ret = $protocol . $base . $ret . $frag;
1151      $ret = rtrim( $ret, '?' );
1152      return $ret;
1153  }
1154  
1155  /**
1156   * Removes an item or items from a query string.
1157   *
1158   * @since 1.5.0
1159   *
1160   * @param string|array $key   Query key or keys to remove.
1161   * @param bool|string  $query Optional. When false uses the current URL. Default false.
1162   * @return string New URL query string.
1163   */
1164  function remove_query_arg( $key, $query = false ) {
1165      if ( is_array( $key ) ) { // Removing multiple keys.
1166          foreach ( $key as $k ) {
1167              $query = add_query_arg( $k, false, $query );
1168          }
1169          return $query;
1170      }
1171      return add_query_arg( $key, false, $query );
1172  }
1173  
1174  /**
1175   * Returns an array of single-use query variable names that can be removed from a URL.
1176   *
1177   * @since 4.4.0
1178   *
1179   * @return string[] An array of parameters to remove from the URL.
1180   */
1181  function wp_removable_query_args() {
1182      $removable_query_args = array(
1183          'activate',
1184          'activated',
1185          'admin_email_remind_later',
1186          'approved',
1187          'deactivate',
1188          'delete_count',
1189          'deleted',
1190          'disabled',
1191          'doing_wp_cron',
1192          'enabled',
1193          'error',
1194          'hotkeys_highlight_first',
1195          'hotkeys_highlight_last',
1196          'locked',
1197          'message',
1198          'same',
1199          'saved',
1200          'settings-updated',
1201          'skipped',
1202          'spammed',
1203          'trashed',
1204          'unspammed',
1205          'untrashed',
1206          'update',
1207          'updated',
1208          'wp-post-new-reload',
1209      );
1210  
1211      /**
1212       * Filters the list of query variables to remove.
1213       *
1214       * @since 4.2.0
1215       *
1216       * @param string[] $removable_query_args An array of query variables to remove from a URL.
1217       */
1218      return apply_filters( 'removable_query_args', $removable_query_args );
1219  }
1220  
1221  /**
1222   * Walks the array while sanitizing the contents.
1223   *
1224   * @since 0.71
1225   * @since 5.5.0 Non-string values are left untouched.
1226   *
1227   * @param array $array Array to walk while sanitizing contents.
1228   * @return array Sanitized $array.
1229   */
1230  function add_magic_quotes( $array ) {
1231      foreach ( (array) $array as $k => $v ) {
1232          if ( is_array( $v ) ) {
1233              $array[ $k ] = add_magic_quotes( $v );
1234          } elseif ( is_string( $v ) ) {
1235              $array[ $k ] = addslashes( $v );
1236          } else {
1237              continue;
1238          }
1239      }
1240  
1241      return $array;
1242  }
1243  
1244  /**
1245   * HTTP request for URI to retrieve content.
1246   *
1247   * @since 1.5.1
1248   *
1249   * @see wp_safe_remote_get()
1250   *
1251   * @param string $uri URI/URL of web page to retrieve.
1252   * @return string|false HTTP content. False on failure.
1253   */
1254  function wp_remote_fopen( $uri ) {
1255      $parsed_url = parse_url( $uri );
1256  
1257      if ( ! $parsed_url || ! is_array( $parsed_url ) ) {
1258          return false;
1259      }
1260  
1261      $options            = array();
1262      $options['timeout'] = 10;
1263  
1264      $response = wp_safe_remote_get( $uri, $options );
1265  
1266      if ( is_wp_error( $response ) ) {
1267          return false;
1268      }
1269  
1270      return wp_remote_retrieve_body( $response );
1271  }
1272  
1273  /**
1274   * Set up the WordPress query.
1275   *
1276   * @since 2.0.0
1277   *
1278   * @global WP       $wp           Current WordPress environment instance.
1279   * @global WP_Query $wp_query     WordPress Query object.
1280   * @global WP_Query $wp_the_query Copy of the WordPress Query object.
1281   *
1282   * @param string|array $query_vars Default WP_Query arguments.
1283   */
1284  function wp( $query_vars = '' ) {
1285      global $wp, $wp_query, $wp_the_query;
1286  
1287      $wp->main( $query_vars );
1288  
1289      if ( ! isset( $wp_the_query ) ) {
1290          $wp_the_query = $wp_query;
1291      }
1292  }
1293  
1294  /**
1295   * Retrieve the description for the HTTP status.
1296   *
1297   * @since 2.3.0
1298   * @since 3.9.0 Added status codes 418, 428, 429, 431, and 511.
1299   * @since 4.5.0 Added status codes 308, 421, and 451.
1300   * @since 5.1.0 Added status code 103.
1301   *
1302   * @global array $wp_header_to_desc
1303   *
1304   * @param int $code HTTP status code.
1305   * @return string Status description if found, an empty string otherwise.
1306   */
1307  function get_status_header_desc( $code ) {
1308      global $wp_header_to_desc;
1309  
1310      $code = absint( $code );
1311  
1312      if ( ! isset( $wp_header_to_desc ) ) {
1313          $wp_header_to_desc = array(
1314              100 => 'Continue',
1315              101 => 'Switching Protocols',
1316              102 => 'Processing',
1317              103 => 'Early Hints',
1318  
1319              200 => 'OK',
1320              201 => 'Created',
1321              202 => 'Accepted',
1322              203 => 'Non-Authoritative Information',
1323              204 => 'No Content',
1324              205 => 'Reset Content',
1325              206 => 'Partial Content',
1326              207 => 'Multi-Status',
1327              226 => 'IM Used',
1328  
1329              300 => 'Multiple Choices',
1330              301 => 'Moved Permanently',
1331              302 => 'Found',
1332              303 => 'See Other',
1333              304 => 'Not Modified',
1334              305 => 'Use Proxy',
1335              306 => 'Reserved',
1336              307 => 'Temporary Redirect',
1337              308 => 'Permanent Redirect',
1338  
1339              400 => 'Bad Request',
1340              401 => 'Unauthorized',
1341              402 => 'Payment Required',
1342              403 => 'Forbidden',
1343              404 => 'Not Found',
1344              405 => 'Method Not Allowed',
1345              406 => 'Not Acceptable',
1346              407 => 'Proxy Authentication Required',
1347              408 => 'Request Timeout',
1348              409 => 'Conflict',
1349              410 => 'Gone',
1350              411 => 'Length Required',
1351              412 => 'Precondition Failed',
1352              413 => 'Request Entity Too Large',
1353              414 => 'Request-URI Too Long',
1354              415 => 'Unsupported Media Type',
1355              416 => 'Requested Range Not Satisfiable',
1356              417 => 'Expectation Failed',
1357              418 => 'I\'m a teapot',
1358              421 => 'Misdirected Request',
1359              422 => 'Unprocessable Entity',
1360              423 => 'Locked',
1361              424 => 'Failed Dependency',
1362              426 => 'Upgrade Required',
1363              428 => 'Precondition Required',
1364              429 => 'Too Many Requests',
1365              431 => 'Request Header Fields Too Large',
1366              451 => 'Unavailable For Legal Reasons',
1367  
1368              500 => 'Internal Server Error',
1369              501 => 'Not Implemented',
1370              502 => 'Bad Gateway',
1371              503 => 'Service Unavailable',
1372              504 => 'Gateway Timeout',
1373              505 => 'HTTP Version Not Supported',
1374              506 => 'Variant Also Negotiates',
1375              507 => 'Insufficient Storage',
1376              510 => 'Not Extended',
1377              511 => 'Network Authentication Required',
1378          );
1379      }
1380  
1381      if ( isset( $wp_header_to_desc[ $code ] ) ) {
1382          return $wp_header_to_desc[ $code ];
1383      } else {
1384          return '';
1385      }
1386  }
1387  
1388  /**
1389   * Set HTTP status header.
1390   *
1391   * @since 2.0.0
1392   * @since 4.4.0 Added the `$description` parameter.
1393   *
1394   * @see get_status_header_desc()
1395   *
1396   * @param int    $code        HTTP status code.
1397   * @param string $description Optional. A custom description for the HTTP status.
1398   */
1399  function status_header( $code, $description = '' ) {
1400      if ( ! $description ) {
1401          $description = get_status_header_desc( $code );
1402      }
1403  
1404      if ( empty( $description ) ) {
1405          return;
1406      }
1407  
1408      $protocol      = wp_get_server_protocol();
1409      $status_header = "$protocol $code $description";
1410      if ( function_exists( 'apply_filters' ) ) {
1411  
1412          /**
1413           * Filters an HTTP status header.
1414           *
1415           * @since 2.2.0
1416           *
1417           * @param string $status_header HTTP status header.
1418           * @param int    $code          HTTP status code.
1419           * @param string $description   Description for the status code.
1420           * @param string $protocol      Server protocol.
1421           */
1422          $status_header = apply_filters( 'status_header', $status_header, $code, $description, $protocol );
1423      }
1424  
1425      if ( ! headers_sent() ) {
1426          header( $status_header, true, $code );
1427      }
1428  }
1429  
1430  /**
1431   * Get the header information to prevent caching.
1432   *
1433   * The several different headers cover the different ways cache prevention
1434   * is handled by different browsers
1435   *
1436   * @since 2.8.0
1437   *
1438   * @return array The associative array of header names and field values.
1439   */
1440  function wp_get_nocache_headers() {
1441      $headers = array(
1442          'Expires'       => 'Wed, 11 Jan 1984 05:00:00 GMT',
1443          'Cache-Control' => 'no-cache, must-revalidate, max-age=0',
1444      );
1445  
1446      if ( function_exists( 'apply_filters' ) ) {
1447          /**
1448           * Filters the cache-controlling headers.
1449           *
1450           * @since 2.8.0
1451           *
1452           * @see wp_get_nocache_headers()
1453           *
1454           * @param array $headers {
1455           *     Header names and field values.
1456           *
1457           *     @type string $Expires       Expires header.
1458           *     @type string $Cache-Control Cache-Control header.
1459           * }
1460           */
1461          $headers = (array) apply_filters( 'nocache_headers', $headers );
1462      }
1463      $headers['Last-Modified'] = false;
1464      return $headers;
1465  }
1466  
1467  /**
1468   * Set the headers to prevent caching for the different browsers.
1469   *
1470   * Different browsers support different nocache headers, so several
1471   * headers must be sent so that all of them get the point that no
1472   * caching should occur.
1473   *
1474   * @since 2.0.0
1475   *
1476   * @see wp_get_nocache_headers()
1477   */
1478  function nocache_headers() {
1479      if ( headers_sent() ) {
1480          return;
1481      }
1482  
1483      $headers = wp_get_nocache_headers();
1484  
1485      unset( $headers['Last-Modified'] );
1486  
1487      header_remove( 'Last-Modified' );
1488  
1489      foreach ( $headers as $name => $field_value ) {
1490          header( "{$name}: {$field_value}" );
1491      }
1492  }
1493  
1494  /**
1495   * Set the headers for caching for 10 days with JavaScript content type.
1496   *
1497   * @since 2.1.0
1498   */
1499  function cache_javascript_headers() {
1500      $expiresOffset = 10 * DAY_IN_SECONDS;
1501  
1502      header( 'Content-Type: text/javascript; charset=' . get_bloginfo( 'charset' ) );
1503      header( 'Vary: Accept-Encoding' ); // Handle proxies.
1504      header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', time() + $expiresOffset ) . ' GMT' );
1505  }
1506  
1507  /**
1508   * Retrieve the number of database queries during the WordPress execution.
1509   *
1510   * @since 2.0.0
1511   *
1512   * @global wpdb $wpdb WordPress database abstraction object.
1513   *
1514   * @return int Number of database queries.
1515   */
1516  function get_num_queries() {
1517      global $wpdb;
1518      return $wpdb->num_queries;
1519  }
1520  
1521  /**
1522   * Whether input is yes or no.
1523   *
1524   * Must be 'y' to be true.
1525   *
1526   * @since 1.0.0
1527   *
1528   * @param string $yn Character string containing either 'y' (yes) or 'n' (no).
1529   * @return bool True if yes, false on anything else.
1530   */
1531  function bool_from_yn( $yn ) {
1532      return ( 'y' === strtolower( $yn ) );
1533  }
1534  
1535  /**
1536   * Load the feed template from the use of an action hook.
1537   *
1538   * If the feed action does not have a hook, then the function will die with a
1539   * message telling the visitor that the feed is not valid.
1540   *
1541   * It is better to only have one hook for each feed.
1542   *
1543   * @since 2.1.0
1544   *
1545   * @global WP_Query $wp_query WordPress Query object.
1546   */
1547  function do_feed() {
1548      global $wp_query;
1549  
1550      $feed = get_query_var( 'feed' );
1551  
1552      // Remove the pad, if present.
1553      $feed = preg_replace( '/^_+/', '', $feed );
1554  
1555      if ( '' === $feed || 'feed' === $feed ) {
1556          $feed = get_default_feed();
1557      }
1558  
1559      if ( ! has_action( "do_feed_{$feed}" ) ) {
1560          wp_die( __( 'Error: This is not a valid feed template.' ), '', array( 'response' => 404 ) );
1561      }
1562  
1563      /**
1564       * Fires once the given feed is loaded.
1565       *
1566       * The dynamic portion of the hook name, `$feed`, refers to the feed template name.
1567       * Possible values include: 'rdf', 'rss', 'rss2', and 'atom'.
1568       *
1569       * @since 2.1.0
1570       * @since 4.4.0 The `$feed` parameter was added.
1571       *
1572       * @param bool   $is_comment_feed Whether the feed is a comment feed.
1573       * @param string $feed            The feed name.
1574       */
1575      do_action( "do_feed_{$feed}", $wp_query->is_comment_feed, $feed );
1576  }
1577  
1578  /**
1579   * Load the RDF RSS 0.91 Feed template.
1580   *
1581   * @since 2.1.0
1582   *
1583   * @see load_template()
1584   */
1585  function do_feed_rdf() {
1586      load_template( ABSPATH . WPINC . '/feed-rdf.php' );
1587  }
1588  
1589  /**
1590   * Load the RSS 1.0 Feed Template.
1591   *
1592   * @since 2.1.0
1593   *
1594   * @see load_template()
1595   */
1596  function do_feed_rss() {
1597      load_template( ABSPATH . WPINC . '/feed-rss.php' );
1598  }
1599  
1600  /**
1601   * Load either the RSS2 comment feed or the RSS2 posts feed.
1602   *
1603   * @since 2.1.0
1604   *
1605   * @see load_template()
1606   *
1607   * @param bool $for_comments True for the comment feed, false for normal feed.
1608   */
1609  function do_feed_rss2( $for_comments ) {
1610      if ( $for_comments ) {
1611          load_template( ABSPATH . WPINC . '/feed-rss2-comments.php' );
1612      } else {
1613          load_template( ABSPATH . WPINC . '/feed-rss2.php' );
1614      }
1615  }
1616  
1617  /**
1618   * Load either Atom comment feed or Atom posts feed.
1619   *
1620   * @since 2.1.0
1621   *
1622   * @see load_template()
1623   *
1624   * @param bool $for_comments True for the comment feed, false for normal feed.
1625   */
1626  function do_feed_atom( $for_comments ) {
1627      if ( $for_comments ) {
1628          load_template( ABSPATH . WPINC . '/feed-atom-comments.php' );
1629      } else {
1630          load_template( ABSPATH . WPINC . '/feed-atom.php' );
1631      }
1632  }
1633  
1634  /**
1635   * Displays the default robots.txt file content.
1636   *
1637   * @since 2.1.0
1638   * @since 5.3.0 Remove the "Disallow: /" output if search engine visiblity is
1639   *              discouraged in favor of robots meta HTML tag in wp_no_robots().
1640   */
1641  function do_robots() {
1642      header( 'Content-Type: text/plain; charset=utf-8' );
1643  
1644      /**
1645       * Fires when displaying the robots.txt file.
1646       *
1647       * @since 2.1.0
1648       */
1649      do_action( 'do_robotstxt' );
1650  
1651      $output = "User-agent: *\n";
1652      $public = get_option( 'blog_public' );
1653  
1654      $site_url = parse_url( site_url() );
1655      $path     = ( ! empty( $site_url['path'] ) ) ? $site_url['path'] : '';
1656      $output  .= "Disallow: $path/wp-admin/\n";
1657      $output  .= "Allow: $path/wp-admin/admin-ajax.php\n";
1658  
1659      /**
1660       * Filters the robots.txt output.
1661       *
1662       * @since 3.0.0
1663       *
1664       * @param string $output The robots.txt output.
1665       * @param bool   $public Whether the site is considered "public".
1666       */
1667      echo apply_filters( 'robots_txt', $output, $public );
1668  }
1669  
1670  /**
1671   * Display the favicon.ico file content.
1672   *
1673   * @since 5.4.0
1674   */
1675  function do_favicon() {
1676      /**
1677       * Fires when serving the favicon.ico file.
1678       *
1679       * @since 5.4.0
1680       */
1681      do_action( 'do_faviconico' );
1682  
1683      wp_redirect( get_site_icon_url( 32, includes_url( 'images/w-logo-blue-white-bg.png' ) ) );
1684      exit;
1685  }
1686  
1687  /**
1688   * Determines whether WordPress is already installed.
1689   *
1690   * The cache will be checked first. If you have a cache plugin, which saves
1691   * the cache values, then this will work. If you use the default WordPress
1692   * cache, and the database goes away, then you might have problems.
1693   *
1694   * Checks for the 'siteurl' option for whether WordPress is installed.
1695   *
1696   * For more information on this and similar theme functions, check out
1697   * the {@link https://developer.wordpress.org/themes/basics/conditional-tags/
1698   * Conditional Tags} article in the Theme Developer Handbook.
1699   *
1700   * @since 2.1.0
1701   *
1702   * @global wpdb $wpdb WordPress database abstraction object.
1703   *
1704   * @return bool Whether the site is already installed.
1705   */
1706  function is_blog_installed() {
1707      global $wpdb;
1708  
1709      /*
1710       * Check cache first. If options table goes away and we have true
1711       * cached, oh well.
1712       */
1713      if ( wp_cache_get( 'is_blog_installed' ) ) {
1714          return true;
1715      }
1716  
1717      $suppress = $wpdb->suppress_errors();
1718      if ( ! wp_installing() ) {
1719          $alloptions = wp_load_alloptions();
1720      }
1721      // If siteurl is not set to autoload, check it specifically.
1722      if ( ! isset( $alloptions['siteurl'] ) ) {
1723          $installed = $wpdb->get_var( "SELECT option_value FROM $wpdb->options WHERE option_name = 'siteurl'" );
1724      } else {
1725          $installed = $alloptions['siteurl'];
1726      }
1727      $wpdb->suppress_errors( $suppress );
1728  
1729      $installed = ! empty( $installed );
1730      wp_cache_set( 'is_blog_installed', $installed );
1731  
1732      if ( $installed ) {
1733          return true;
1734      }
1735  
1736      // If visiting repair.php, return true and let it take over.
1737      if ( defined( 'WP_REPAIRING' ) ) {
1738          return true;
1739      }
1740  
1741      $suppress = $wpdb->suppress_errors();
1742  
1743      /*
1744       * Loop over the WP tables. If none exist, then scratch installation is allowed.
1745       * If one or more exist, suggest table repair since we got here because the
1746       * options table could not be accessed.
1747       */
1748      $wp_tables = $wpdb->tables();
1749      foreach ( $wp_tables as $table ) {
1750          // The existence of custom user tables shouldn't suggest an insane state or prevent a clean installation.
1751          if ( defined( 'CUSTOM_USER_TABLE' ) && CUSTOM_USER_TABLE == $table ) {
1752              continue;
1753          }
1754          if ( defined( 'CUSTOM_USER_META_TABLE' ) && CUSTOM_USER_META_TABLE == $table ) {
1755              continue;
1756          }
1757  
1758          if ( ! $wpdb->get_results( "DESCRIBE $table;" ) ) {
1759              continue;
1760          }
1761  
1762          // One or more tables exist. We are insane.
1763  
1764          wp_load_translations_early();
1765  
1766          // Die with a DB error.
1767          $wpdb->error = sprintf(
1768              /* translators: %s: Database repair URL. */
1769              __( 'One or more database tables are unavailable. The database may need to be <a href="%s">repaired</a>.' ),
1770              'maint/repair.php?referrer=is_blog_installed'
1771          );
1772  
1773          dead_db();
1774      }
1775  
1776      $wpdb->suppress_errors( $suppress );
1777  
1778      wp_cache_set( 'is_blog_installed', false );
1779  
1780      return false;
1781  }
1782  
1783  /**
1784   * Retrieve URL with nonce added to URL query.
1785   *
1786   * @since 2.0.4
1787   *
1788   * @param string     $actionurl URL to add nonce action.
1789   * @param int|string $action    Optional. Nonce action name. Default -1.
1790   * @param string     $name      Optional. Nonce name. Default '_wpnonce'.
1791   * @return string Escaped URL with nonce action added.
1792   */
1793  function wp_nonce_url( $actionurl, $action = -1, $name = '_wpnonce' ) {
1794      $actionurl = str_replace( '&amp;', '&', $actionurl );
1795      return esc_html( add_query_arg( $name, wp_create_nonce( $action ), $actionurl ) );
1796  }
1797  
1798  /**
1799   * Retrieve or display nonce hidden field for forms.
1800   *
1801   * The nonce field is used to validate that the contents of the form came from
1802   * the location on the current site and not somewhere else. The nonce does not
1803   * offer absolute protection, but should protect against most cases. It is very
1804   * important to use nonce field in forms.
1805   *
1806   * The $action and $name are optional, but if you want to have better security,
1807   * it is strongly suggested to set those two parameters. It is easier to just
1808   * call the function without any parameters, because validation of the nonce
1809   * doesn't require any parameters, but since crackers know what the default is
1810   * it won't be difficult for them to find a way around your nonce and cause
1811   * damage.
1812   *
1813   * The input name will be whatever $name value you gave. The input value will be
1814   * the nonce creation value.
1815   *
1816   * @since 2.0.4
1817   *
1818   * @param int|string $action  Optional. Action name. Default -1.
1819   * @param string     $name    Optional. Nonce name. Default '_wpnonce'.
1820   * @param bool       $referer Optional. Whether to set the referer field for validation. Default true.
1821   * @param bool       $echo    Optional. Whether to display or return hidden form field. Default true.
1822   * @return string Nonce field HTML markup.
1823   */
1824  function wp_nonce_field( $action = -1, $name = '_wpnonce', $referer = true, $echo = true ) {
1825      $name        = esc_attr( $name );
1826      $nonce_field = '<input type="hidden" id="' . $name . '" name="' . $name . '" value="' . wp_create_nonce( $action ) . '" />';
1827  
1828      if ( $referer ) {
1829          $nonce_field .= wp_referer_field( false );
1830      }
1831  
1832      if ( $echo ) {
1833          echo $nonce_field;
1834      }
1835  
1836      return $nonce_field;
1837  }
1838  
1839  /**
1840   * Retrieve or display referer hidden field for forms.
1841   *
1842   * The referer link is the current Request URI from the server super global. The
1843   * input name is '_wp_http_referer', in case you wanted to check manually.
1844   *
1845   * @since 2.0.4
1846   *
1847   * @param bool $echo Optional. Whether to echo or return the referer field. Default true.
1848   * @return string Referer field HTML markup.
1849   */
1850  function wp_referer_field( $echo = true ) {
1851      $referer_field = '<input type="hidden" name="_wp_http_referer" value="' . esc_attr( wp_unslash( $_SERVER['REQUEST_URI'] ) ) . '" />';
1852  
1853      if ( $echo ) {
1854          echo $referer_field;
1855      }
1856  
1857      return $referer_field;
1858  }
1859  
1860  /**
1861   * Retrieve or display original referer hidden field for forms.
1862   *
1863   * The input name is '_wp_original_http_referer' and will be either the same
1864   * value of wp_referer_field(), if that was posted already or it will be the
1865   * current page, if it doesn't exist.
1866   *
1867   * @since 2.0.4
1868   *
1869   * @param bool   $echo         Optional. Whether to echo the original http referer. Default true.
1870   * @param string $jump_back_to Optional. Can be 'previous' or page you want to jump back to.
1871   *                             Default 'current'.
1872   * @return string Original referer field.
1873   */
1874  function wp_original_referer_field( $echo = true, $jump_back_to = 'current' ) {
1875      $ref = wp_get_original_referer();
1876  
1877      if ( ! $ref ) {
1878          $ref = ( 'previous' === $jump_back_to ) ? wp_get_referer() : wp_unslash( $_SERVER['REQUEST_URI'] );
1879      }
1880  
1881      $orig_referer_field = '<input type="hidden" name="_wp_original_http_referer" value="' . esc_attr( $ref ) . '" />';
1882  
1883      if ( $echo ) {
1884          echo $orig_referer_field;
1885      }
1886  
1887      return $orig_referer_field;
1888  }
1889  
1890  /**
1891   * Retrieve referer from '_wp_http_referer' or HTTP referer.
1892   *
1893   * If it's the same as the current request URL, will return false.
1894   *
1895   * @since 2.0.4
1896   *
1897   * @return string|false Referer URL on success, false on failure.
1898   */
1899  function wp_get_referer() {
1900      if ( ! function_exists( 'wp_validate_redirect' ) ) {
1901          return false;
1902      }
1903  
1904      $ref = wp_get_raw_referer();
1905  
1906      if ( $ref && wp_unslash( $_SERVER['REQUEST_URI'] ) !== $ref && home_url() . wp_unslash( $_SERVER['REQUEST_URI'] ) !== $ref ) {
1907          return wp_validate_redirect( $ref, false );
1908      }
1909  
1910      return false;
1911  }
1912  
1913  /**
1914   * Retrieves unvalidated referer from '_wp_http_referer' or HTTP referer.
1915   *
1916   * Do not use for redirects, use wp_get_referer() instead.
1917   *
1918   * @since 4.5.0
1919   *
1920   * @return string|false Referer URL on success, false on failure.
1921   */
1922  function wp_get_raw_referer() {
1923      if ( ! empty( $_REQUEST['_wp_http_referer'] ) ) {
1924          return wp_unslash( $_REQUEST['_wp_http_referer'] );
1925      } elseif ( ! empty( $_SERVER['HTTP_REFERER'] ) ) {
1926          return wp_unslash( $_SERVER['HTTP_REFERER'] );
1927      }
1928  
1929      return false;
1930  }
1931  
1932  /**
1933   * Retrieve original referer that was posted, if it exists.
1934   *
1935   * @since 2.0.4
1936   *
1937   * @return string|false Original referer URL on success, false on failure.
1938   */
1939  function wp_get_original_referer() {
1940      if ( ! empty( $_REQUEST['_wp_original_http_referer'] ) && function_exists( 'wp_validate_redirect' ) ) {
1941          return wp_validate_redirect( wp_unslash( $_REQUEST['_wp_original_http_referer'] ), false );
1942      }
1943  
1944      return false;
1945  }
1946  
1947  /**
1948   * Recursive directory creation based on full path.
1949   *
1950   * Will attempt to set permissions on folders.
1951   *
1952   * @since 2.0.1
1953   *
1954   * @param string $target Full path to attempt to create.
1955   * @return bool Whether the path was created. True if path already exists.
1956   */
1957  function wp_mkdir_p( $target ) {
1958      $wrapper = null;
1959  
1960      // Strip the protocol.
1961      if ( wp_is_stream( $target ) ) {
1962          list( $wrapper, $target ) = explode( '://', $target, 2 );
1963      }
1964  
1965      // From php.net/mkdir user contributed notes.
1966      $target = str_replace( '//', '/', $target );
1967  
1968      // Put the wrapper back on the target.
1969      if ( null !== $wrapper ) {
1970          $target = $wrapper . '://' . $target;
1971      }
1972  
1973      /*
1974       * Safe mode fails with a trailing slash under certain PHP versions.
1975       * Use rtrim() instead of untrailingslashit to avoid formatting.php dependency.
1976       */
1977      $target = rtrim( $target, '/' );
1978      if ( empty( $target ) ) {
1979          $target = '/';
1980      }
1981  
1982      if ( file_exists( $target ) ) {
1983          return @is_dir( $target );
1984      }
1985  
1986      // Do not allow path traversals.
1987      if ( false !== strpos( $target, '../' ) || false !== strpos( $target, '..' . DIRECTORY_SEPARATOR ) ) {
1988          return false;
1989      }
1990  
1991      // We need to find the permissions of the parent folder that exists and inherit that.
1992      $target_parent = dirname( $target );
1993      while ( '.' !== $target_parent && ! is_dir( $target_parent ) && dirname( $target_parent ) !== $target_parent ) {
1994          $target_parent = dirname( $target_parent );
1995      }
1996  
1997      // Get the permission bits.
1998      $stat = @stat( $target_parent );
1999      if ( $stat ) {
2000          $dir_perms = $stat['mode'] & 0007777;
2001      } else {
2002          $dir_perms = 0777;
2003      }
2004  
2005      if ( @mkdir( $target, $dir_perms, true ) ) {
2006  
2007          /*
2008           * If a umask is set that modifies $dir_perms, we'll have to re-set
2009           * the $dir_perms correctly with chmod()
2010           */
2011          if ( ( $dir_perms & ~umask() ) != $dir_perms ) {
2012              $folder_parts = explode( '/', substr( $target, strlen( $target_parent ) + 1 ) );
2013              for ( $i = 1, $c = count( $folder_parts ); $i <= $c; $i++ ) {
2014                  chmod( $target_parent . '/' . implode( '/', array_slice( $folder_parts, 0, $i ) ), $dir_perms );
2015              }
2016          }
2017  
2018          return true;
2019      }
2020  
2021      return false;
2022  }
2023  
2024  /**
2025   * Test if a given filesystem path is absolute.
2026   *
2027   * For example, '/foo/bar', or 'c:\windows'.
2028   *
2029   * @since 2.5.0
2030   *
2031   * @param string $path File path.
2032   * @return bool True if path is absolute, false is not absolute.
2033   */
2034  function path_is_absolute( $path ) {
2035      /*
2036       * Check to see if the path is a stream and check to see if its an actual
2037       * path or file as realpath() does not support stream wrappers.
2038       */
2039      if ( wp_is_stream( $path ) && ( is_dir( $path ) || is_file( $path ) ) ) {
2040          return true;
2041      }
2042  
2043      /*
2044       * This is definitive if true but fails if $path does not exist or contains
2045       * a symbolic link.
2046       */
2047      if ( realpath( $path ) == $path ) {
2048          return true;
2049      }
2050  
2051      if ( strlen( $path ) == 0 || '.' === $path[0] ) {
2052          return false;
2053      }
2054  
2055      // Windows allows absolute paths like this.
2056      if ( preg_match( '#^[a-zA-Z]:\\\\#', $path ) ) {
2057          return true;
2058      }
2059  
2060      // A path starting with / or \ is absolute; anything else is relative.
2061      return ( '/' === $path[0] || '\\' === $path[0] );
2062  }
2063  
2064  /**
2065   * Join two filesystem paths together.
2066   *
2067   * For example, 'give me $path relative to $base'. If the $path is absolute,
2068   * then it the full path is returned.
2069   *
2070   * @since 2.5.0
2071   *
2072   * @param string $base Base path.
2073   * @param string $path Path relative to $base.
2074   * @return string The path with the base or absolute path.
2075   */
2076  function path_join( $base, $path ) {
2077      if ( path_is_absolute( $path ) ) {
2078          return $path;
2079      }
2080  
2081      return rtrim( $base, '/' ) . '/' . ltrim( $path, '/' );
2082  }
2083  
2084  /**
2085   * Normalize a filesystem path.
2086   *
2087   * On windows systems, replaces backslashes with forward slashes
2088   * and forces upper-case drive letters.
2089   * Allows for two leading slashes for Windows network shares, but
2090   * ensures that all other duplicate slashes are reduced to a single.
2091   *
2092   * @since 3.9.0
2093   * @since 4.4.0 Ensures upper-case drive letters on Windows systems.
2094   * @since 4.5.0 Allows for Windows network shares.
2095   * @since 4.9.7 Allows for PHP file wrappers.
2096   *
2097   * @param string $path Path to normalize.
2098   * @return string Normalized path.
2099   */
2100  function wp_normalize_path( $path ) {
2101      $wrapper = '';
2102  
2103      if ( wp_is_stream( $path ) ) {
2104          list( $wrapper, $path ) = explode( '://', $path, 2 );
2105  
2106          $wrapper .= '://';
2107      }
2108  
2109      // Standardise all paths to use '/'.
2110      $path = str_replace( '\\', '/', $path );
2111  
2112      // Replace multiple slashes down to a singular, allowing for network shares having two slashes.
2113      $path = preg_replace( '|(?<=.)/+|', '/', $path );
2114  
2115      // Windows paths should uppercase the drive letter.
2116      if ( ':' === substr( $path, 1, 1 ) ) {
2117          $path = ucfirst( $path );
2118      }
2119  
2120      return $wrapper . $path;
2121  }
2122  
2123  /**
2124   * Determine a writable directory for temporary files.
2125   *
2126   * Function's preference is the return value of sys_get_temp_dir(),
2127   * followed by your PHP temporary upload directory, followed by WP_CONTENT_DIR,
2128   * before finally defaulting to /tmp/
2129   *
2130   * In the event that this function does not find a writable location,
2131   * It may be overridden by the WP_TEMP_DIR constant in your wp-config.php file.
2132   *
2133   * @since 2.5.0
2134   *
2135   * @return string Writable temporary directory.
2136   */
2137  function get_temp_dir() {
2138      static $temp = '';
2139      if ( defined( 'WP_TEMP_DIR' ) ) {
2140          return trailingslashit( WP_TEMP_DIR );
2141      }
2142  
2143      if ( $temp ) {
2144          return trailingslashit( $temp );
2145      }
2146  
2147      if ( function_exists( 'sys_get_temp_dir' ) ) {
2148          $temp = sys_get_temp_dir();
2149          if ( @is_dir( $temp ) && wp_is_writable( $temp ) ) {
2150              return trailingslashit( $temp );
2151          }
2152      }
2153  
2154      $temp = ini_get( 'upload_tmp_dir' );
2155      if ( @is_dir( $temp ) && wp_is_writable( $temp ) ) {
2156          return trailingslashit( $temp );
2157      }
2158  
2159      $temp = WP_CONTENT_DIR . '/';
2160      if ( is_dir( $temp ) && wp_is_writable( $temp ) ) {
2161          return $temp;
2162      }
2163  
2164      return '/tmp/';
2165  }
2166  
2167  /**
2168   * Determine if a directory is writable.
2169   *
2170   * This function is used to work around certain ACL issues in PHP primarily
2171   * affecting Windows Servers.
2172   *
2173   * @since 3.6.0
2174   *
2175   * @see win_is_writable()
2176   *
2177   * @param string $path Path to check for write-ability.
2178   * @return bool Whether the path is writable.
2179   */
2180  function wp_is_writable( $path ) {
2181      if ( 'WIN' === strtoupper( substr( PHP_OS, 0, 3 ) ) ) {
2182          return win_is_writable( $path );
2183      } else {
2184          return @is_writable( $path );
2185      }
2186  }
2187  
2188  /**
2189   * Workaround for Windows bug in is_writable() function
2190   *
2191   * PHP has issues with Windows ACL's for determine if a
2192   * directory is writable or not, this works around them by
2193   * checking the ability to open files rather than relying
2194   * upon PHP to interprate the OS ACL.
2195   *
2196   * @since 2.8.0
2197   *
2198   * @see https://bugs.php.net/bug.php?id=27609
2199   * @see https://bugs.php.net/bug.php?id=30931
2200   *
2201   * @param string $path Windows path to check for write-ability.
2202   * @return bool Whether the path is writable.
2203   */
2204  function win_is_writable( $path ) {
2205      if ( '/' === $path[ strlen( $path ) - 1 ] ) {
2206          // If it looks like a directory, check a random file within the directory.
2207          return win_is_writable( $path . uniqid( mt_rand() ) . '.tmp' );
2208      } elseif ( is_dir( $path ) ) {
2209          // If it's a directory (and not a file), check a random file within the directory.
2210          return win_is_writable( $path . '/' . uniqid( mt_rand() ) . '.tmp' );
2211      }
2212  
2213      // Check tmp file for read/write capabilities.
2214      $should_delete_tmp_file = ! file_exists( $path );
2215  
2216      $f = @fopen( $path, 'a' );
2217      if ( false === $f ) {
2218          return false;
2219      }
2220      fclose( $f );
2221  
2222      if ( $should_delete_tmp_file ) {
2223          unlink( $path );
2224      }
2225  
2226      return true;
2227  }
2228  
2229  /**
2230   * Retrieves uploads directory information.
2231   *
2232   * Same as wp_upload_dir() but "light weight" as it doesn't attempt to create the uploads directory.
2233   * Intended for use in themes, when only 'basedir' and 'baseurl' are needed, generally in all cases
2234   * when not uploading files.
2235   *
2236   * @since 4.5.0
2237   *
2238   * @see wp_upload_dir()
2239   *
2240   * @return array See wp_upload_dir() for description.
2241   */
2242  function wp_get_upload_dir() {
2243      return wp_upload_dir( null, false );
2244  }
2245  
2246  /**
2247   * Returns an array containing the current upload directory's path and URL.
2248   *
2249   * Checks the 'upload_path' option, which should be from the web root folder,
2250   * and if it isn't empty it will be used. If it is empty, then the path will be
2251   * 'WP_CONTENT_DIR/uploads'. If the 'UPLOADS' constant is defined, then it will
2252   * override the 'upload_path' option and 'WP_CONTENT_DIR/uploads' path.
2253   *
2254   * The upload URL path is set either by the 'upload_url_path' option or by using
2255   * the 'WP_CONTENT_URL' constant and appending '/uploads' to the path.
2256   *
2257   * If the 'uploads_use_yearmonth_folders' is set to true (checkbox if checked in
2258   * the administration settings panel), then the time will be used. The format
2259   * will be year first and then month.
2260   *
2261   * If the path couldn't be created, then an error will be returned with the key
2262   * 'error' containing the error message. The error suggests that the parent
2263   * directory is not writable by the server.
2264   *
2265   * @since 2.0.0
2266   * @uses _wp_upload_dir()
2267   *
2268   * @param string $time Optional. Time formatted in 'yyyy/mm'. Default null.
2269   * @param bool   $create_dir Optional. Whether to check and create the uploads directory.
2270   *                           Default true for backward compatibility.
2271   * @param bool   $refresh_cache Optional. Whether to refresh the cache. Default false.
2272   * @return array {
2273   *     Array of information about the upload directory.
2274   *
2275   *     @type string       $path    Base directory and subdirectory or full path to upload directory.
2276   *     @type string       $url     Base URL and subdirectory or absolute URL to upload directory.
2277   *     @type string       $subdir  Subdirectory if uploads use year/month folders option is on.
2278   *     @type string       $basedir Path without subdir.
2279   *     @type string       $baseurl URL path without subdir.
2280   *     @type string|false $error   False or error message.
2281   * }
2282   */
2283  function wp_upload_dir( $time = null, $create_dir = true, $refresh_cache = false ) {
2284      static $cache = array(), $tested_paths = array();
2285  
2286      $key = sprintf( '%d-%s', get_current_blog_id(), (string) $time );
2287  
2288      if ( $refresh_cache || empty( $cache[ $key ] ) ) {
2289          $cache[ $key ] = _wp_upload_dir( $time );
2290      }
2291  
2292      /**
2293       * Filters the uploads directory data.
2294       *
2295       * @since 2.0.0
2296       *
2297       * @param array $uploads {
2298       *     Array of information about the upload directory.
2299       *
2300       *     @type string       $path    Base directory and subdirectory or full path to upload directory.
2301       *     @type string       $url     Base URL and subdirectory or absolute URL to upload directory.
2302       *     @type string       $subdir  Subdirectory if uploads use year/month folders option is on.
2303       *     @type string       $basedir Path without subdir.
2304       *     @type string       $baseurl URL path without subdir.
2305       *     @type string|false $error   False or error message.
2306       * }
2307       */
2308      $uploads = apply_filters( 'upload_dir', $cache[ $key ] );
2309  
2310      if ( $create_dir ) {
2311          $path = $uploads['path'];
2312  
2313          if ( array_key_exists( $path, $tested_paths ) ) {
2314              $uploads['error'] = $tested_paths[ $path ];
2315          } else {
2316              if ( ! wp_mkdir_p( $path ) ) {
2317                  if ( 0 === strpos( $uploads['basedir'], ABSPATH ) ) {
2318                      $error_path = str_replace( ABSPATH, '', $uploads['basedir'] ) . $uploads['subdir'];
2319                  } else {
2320                      $error_path = wp_basename( $uploads['basedir'] ) . $uploads['subdir'];
2321                  }
2322  
2323                  $uploads['error'] = sprintf(
2324                      /* translators: %s: Directory path. */
2325                      __( 'Unable to create directory %s. Is its parent directory writable by the server?' ),
2326                      esc_html( $error_path )
2327                  );
2328              }
2329  
2330              $tested_paths[ $path ] = $uploads['error'];
2331          }
2332      }
2333  
2334      return $uploads;
2335  }
2336  
2337  /**
2338   * A non-filtered, non-cached version of wp_upload_dir() that doesn't check the path.
2339   *
2340   * @since 4.5.0
2341   * @access private
2342   *
2343   * @param string $time Optional. Time formatted in 'yyyy/mm'. Default null.
2344   * @return array See wp_upload_dir()
2345   */
2346  function _wp_upload_dir( $time = null ) {
2347      $siteurl     = get_option( 'siteurl' );
2348      $upload_path = trim( get_option( 'upload_path' ) );
2349  
2350      if ( empty( $upload_path ) || 'wp-content/uploads' === $upload_path ) {
2351          $dir = WP_CONTENT_DIR . '/uploads';
2352      } elseif ( 0 !== strpos( $upload_path, ABSPATH ) ) {
2353          // $dir is absolute, $upload_path is (maybe) relative to ABSPATH.
2354          $dir = path_join( ABSPATH, $upload_path );
2355      } else {
2356          $dir = $upload_path;
2357      }
2358  
2359      $url = get_option( 'upload_url_path' );
2360      if ( ! $url ) {
2361          if ( empty( $upload_path ) || ( 'wp-content/uploads' === $upload_path ) || ( $upload_path == $dir ) ) {
2362              $url = WP_CONTENT_URL . '/uploads';
2363          } else {
2364              $url = trailingslashit( $siteurl ) . $upload_path;
2365          }
2366      }
2367  
2368      /*
2369       * Honor the value of UPLOADS. This happens as long as ms-files rewriting is disabled.
2370       * We also sometimes obey UPLOADS when rewriting is enabled -- see the next block.
2371       */
2372      if ( defined( 'UPLOADS' ) && ! ( is_multisite() && get_site_option( 'ms_files_rewriting' ) ) ) {
2373          $dir = ABSPATH . UPLOADS;
2374          $url = trailingslashit( $siteurl ) . UPLOADS;
2375      }
2376  
2377      // If multisite (and if not the main site in a post-MU network).
2378      if ( is_multisite() && ! ( is_main_network() && is_main_site() && defined( 'MULTISITE' ) ) ) {
2379  
2380          if ( ! get_site_option( 'ms_files_rewriting' ) ) {
2381              /*
2382               * If ms-files rewriting is disabled (networks created post-3.5), it is fairly
2383               * straightforward: Append sites/%d if we're not on the main site (for post-MU
2384               * networks). (The extra directory prevents a four-digit ID from conflicting with
2385               * a year-based directory for the main site. But if a MU-era network has disabled
2386               * ms-files rewriting manually, they don't need the extra directory, as they never
2387               * had wp-content/uploads for the main site.)
2388               */
2389  
2390              if ( defined( 'MULTISITE' ) ) {
2391                  $ms_dir = '/sites/' . get_current_blog_id();
2392              } else {
2393                  $ms_dir = '/' . get_current_blog_id();
2394              }
2395  
2396              $dir .= $ms_dir;
2397              $url .= $ms_dir;
2398  
2399          } elseif ( defined( 'UPLOADS' ) && ! ms_is_switched() ) {
2400              /*
2401               * Handle the old-form ms-files.php rewriting if the network still has that enabled.
2402               * When ms-files rewriting is enabled, then we only listen to UPLOADS when:
2403               * 1) We are not on the main site in a post-MU network, as wp-content/uploads is used
2404               *    there, and
2405               * 2) We are not switched, as ms_upload_constants() hardcodes these constants to reflect
2406               *    the original blog ID.
2407               *
2408               * Rather than UPLOADS, we actually use BLOGUPLOADDIR if it is set, as it is absolute.
2409               * (And it will be set, see ms_upload_constants().) Otherwise, UPLOADS can be used, as
2410               * as it is relative to ABSPATH. For the final piece: when UPLOADS is used with ms-files
2411               * rewriting in multisite, the resulting URL is /files. (#WP22702 for background.)
2412               */
2413  
2414              if ( defined( 'BLOGUPLOADDIR' ) ) {
2415                  $dir = untrailingslashit( BLOGUPLOADDIR );
2416              } else {
2417                  $dir = ABSPATH . UPLOADS;
2418              }
2419              $url = trailingslashit( $siteurl ) . 'files';
2420          }
2421      }
2422  
2423      $basedir = $dir;
2424      $baseurl = $url;
2425  
2426      $subdir = '';
2427      if ( get_option( 'uploads_use_yearmonth_folders' ) ) {
2428          // Generate the yearly and monthly directories.
2429          if ( ! $time ) {
2430              $time = current_time( 'mysql' );
2431          }
2432          $y      = substr( $time, 0, 4 );
2433          $m      = substr( $time, 5, 2 );
2434          $subdir = "/$y/$m";
2435      }
2436  
2437      $dir .= $subdir;
2438      $url .= $subdir;
2439  
2440      return array(
2441          'path'    => $dir,
2442          'url'     => $url,
2443          'subdir'  => $subdir,
2444          'basedir' => $basedir,
2445          'baseurl' => $baseurl,
2446          'error'   => false,
2447      );
2448  }
2449  
2450  /**
2451   * Get a filename that is sanitized and unique for the given directory.
2452   *
2453   * If the filename is not unique, then a number will be added to the filename
2454   * before the extension, and will continue adding numbers until the filename
2455   * is unique.
2456   *
2457   * The callback function allows the caller to use their own method to create
2458   * unique file names. If defined, the callback should take three arguments:
2459   * - directory, base filename, and extension - and return a unique filename.
2460   *
2461   * @since 2.5.0
2462   *
2463   * @param string   $dir                      Directory.
2464   * @param string   $filename                 File name.
2465   * @param callable $unique_filename_callback Callback. Default null.
2466   * @return string New filename, if given wasn't unique.
2467   */
2468  function wp_unique_filename( $dir, $filename, $unique_filename_callback = null ) {
2469      // Sanitize the file name before we begin processing.
2470      $filename = sanitize_file_name( $filename );
2471      $ext2     = null;
2472  
2473      // Separate the filename into a name and extension.
2474      $ext  = pathinfo( $filename, PATHINFO_EXTENSION );
2475      $name = pathinfo( $filename, PATHINFO_BASENAME );
2476  
2477      if ( $ext ) {
2478          $ext = '.' . $ext;
2479      }
2480  
2481      // Edge case: if file is named '.ext', treat as an empty name.
2482      if ( $name === $ext ) {
2483          $name = '';
2484      }
2485  
2486      /*
2487       * Increment the file number until we have a unique file to save in $dir.
2488       * Use callback if supplied.
2489       */
2490      if ( $unique_filename_callback && is_callable( $unique_filename_callback ) ) {
2491          $filename = call_user_func( $unique_filename_callback, $dir, $name, $ext );
2492      } else {
2493          $number = '';
2494          $fname  = pathinfo( $filename, PATHINFO_FILENAME );
2495  
2496          // Always append a number to file names that can potentially match image sub-size file names.
2497          if ( $fname && preg_match( '/-(?:\d+x\d+|scaled|rotated)$/', $fname ) ) {
2498              $number = 1;
2499  
2500              // At this point the file name may not be unique. This is tested below and the $number is incremented.
2501              $filename = str_replace( "{$fname}{$ext}", "{$fname}-{$number}{$ext}", $filename );
2502          }
2503  
2504          // Change '.ext' to lower case.
2505          if ( $ext && strtolower( $ext ) != $ext ) {
2506              $ext2      = strtolower( $ext );
2507              $filename2 = preg_replace( '|' . preg_quote( $ext ) . '$|', $ext2, $filename );
2508  
2509              // Check for both lower and upper case extension or image sub-sizes may be overwritten.
2510              while ( file_exists( $dir . "/{$filename}" ) || file_exists( $dir . "/{$filename2}" ) ) {
2511                  $new_number = (int) $number + 1;
2512                  $filename   = str_replace( array( "-{$number}{$ext}", "{$number}{$ext}" ), "-{$new_number}{$ext}", $filename );
2513                  $filename2  = str_replace( array( "-{$number}{$ext2}", "{$number}{$ext2}" ), "-{$new_number}{$ext2}", $filename2 );
2514                  $number     = $new_number;
2515              }
2516  
2517              $filename = $filename2;
2518          } else {
2519              while ( file_exists( $dir . "/{$filename}" ) ) {
2520                  $new_number = (int) $number + 1;
2521  
2522                  if ( '' === "{$number}{$ext}" ) {
2523                      $filename = "{$filename}-{$new_number}";
2524                  } else {
2525                      $filename = str_replace( array( "-{$number}{$ext}", "{$number}{$ext}" ), "-{$new_number}{$ext}", $filename );
2526                  }
2527  
2528                  $number = $new_number;
2529              }
2530          }
2531  
2532          // Prevent collisions with existing file names that contain dimension-like strings
2533          // (whether they are subsizes or originals uploaded prior to #42437).
2534          $upload_dir = wp_get_upload_dir();
2535  
2536          // The (resized) image files would have name and extension, and will be in the uploads dir.
2537          if ( $name && $ext && @is_dir( $dir ) && false !== strpos( $dir, $upload_dir['basedir'] ) ) {
2538              /**
2539               * Filters the file list used for calculating a unique filename for a newly added file.
2540               *
2541               * Returning an array from the filter will effectively short-circuit retrieval
2542               * from the filesystem and return the passed value instead.
2543               *
2544               * @since 5.5.0
2545               *
2546               * @param array|null $files    The list of files to use for filename comparisons.
2547               *                             Default null (to retrieve the list from the filesystem).
2548               * @param string     $dir      The directory for the new file.
2549               * @param string     $filename The proposed filename for the new file.
2550               */
2551              $files = apply_filters( 'pre_wp_unique_filename_file_list', null, $dir, $filename );
2552  
2553              if ( null === $files ) {
2554                  // List of all files and directories contained in $dir.
2555                  $files = @scandir( $dir );
2556              }
2557  
2558              if ( ! empty( $files ) ) {
2559                  // Remove "dot" dirs.
2560                  $files = array_diff( $files, array( '.', '..' ) );
2561              }
2562  
2563              if ( ! empty( $files ) ) {
2564                  // The extension case may have changed above.
2565                  $new_ext = ! empty( $ext2 ) ? $ext2 : $ext;
2566  
2567                  // Ensure this never goes into infinite loop
2568                  // as it uses pathinfo() and regex in the check, but string replacement for the changes.
2569                  $count = count( $files );
2570                  $i     = 0;
2571  
2572                  while ( $i <= $count && _wp_check_existing_file_names( $filename, $files ) ) {
2573                      $new_number = (int) $number + 1;
2574                      $filename   = str_replace( array( "-{$number}{$new_ext}", "{$number}{$new_ext}" ), "-{$new_number}{$new_ext}", $filename );
2575                      $number     = $new_number;
2576                      $i++;
2577                  }
2578              }
2579          }
2580      }
2581  
2582      /**
2583       * Filters the result when generating a unique file name.
2584       *
2585       * @since 4.5.0
2586       *
2587       * @param string        $filename                 Unique file name.
2588       * @param string        $ext                      File extension, eg. ".png".
2589       * @param string        $dir                      Directory path.
2590       * @param callable|null $unique_filename_callback Callback function that generates the unique file name.
2591       */
2592      return apply_filters( 'wp_unique_filename', $filename, $ext, $dir, $unique_filename_callback );
2593  }
2594  
2595  /**
2596   * Helper function to check if a file name could match an existing image sub-size file name.
2597   *
2598   * @since 5.3.1
2599   * @access private
2600   *
2601   * @param string $filename The file name to check.
2602   * @param array  $files    An array of existing files in the directory.
2603   * @return bool True if the tested file name could match an existing file, false otherwise.
2604   */
2605  function _wp_check_existing_file_names( $filename, $files ) {
2606      $fname = pathinfo( $filename, PATHINFO_FILENAME );
2607      $ext   = pathinfo( $filename, PATHINFO_EXTENSION );
2608  
2609      // Edge case, file names like `.ext`.
2610      if ( empty( $fname ) ) {
2611          return false;
2612      }
2613  
2614      if ( $ext ) {
2615          $ext = ".$ext";
2616      }
2617  
2618      $regex = '/^' . preg_quote( $fname ) . '-(?:\d+x\d+|scaled|rotated)' . preg_quote( $ext ) . '$/i';
2619  
2620      foreach ( $files as $file ) {
2621          if ( preg_match( $regex, $file ) ) {
2622              return true;
2623          }
2624      }
2625  
2626      return false;
2627  }
2628  
2629  /**
2630   * Create a file in the upload folder with given content.
2631   *
2632   * If there is an error, then the key 'error' will exist with the error message.
2633   * If success, then the key 'file' will have the unique file path, the 'url' key
2634   * will have the link to the new file. and the 'error' key will be set to false.
2635   *
2636   * This function will not move an uploaded file to the upload folder. It will
2637   * create a new file with the content in $bits parameter. If you move the upload
2638   * file, read the content of the uploaded file, and then you can give the
2639   * filename and content to this function, which will add it to the upload
2640   * folder.
2641   *
2642   * The permissions will be set on the new file automatically by this function.
2643   *
2644   * @since 2.0.0
2645   *
2646   * @param string      $name       Filename.
2647   * @param null|string $deprecated Never used. Set to null.
2648   * @param string      $bits       File content
2649   * @param string      $time       Optional. Time formatted in 'yyyy/mm'. Default null.
2650   * @return array {
2651   *     Information about the newly-uploaded file.
2652   *
2653   *     @type string       $file  Filename of the newly-uploaded file.
2654   *     @type string       $url   URL of the uploaded file.
2655   *     @type string       $type  File type.
2656   *     @type string|false $error Error message, if there has been an error.
2657   * }
2658   */
2659  function wp_upload_bits( $name, $deprecated, $bits, $time = null ) {
2660      if ( ! empty( $deprecated ) ) {
2661          _deprecated_argument( __FUNCTION__, '2.0.0' );
2662      }
2663  
2664      if ( empty( $name ) ) {
2665          return array( 'error' => __( 'Empty filename' ) );
2666      }
2667  
2668      $wp_filetype = wp_check_filetype( $name );
2669      if ( ! $wp_filetype['ext'] && ! current_user_can( 'unfiltered_upload' ) ) {
2670          return array( 'error' => __( 'Sorry, this file type is not permitted for security reasons.' ) );
2671      }
2672  
2673      $upload = wp_upload_dir( $time );
2674  
2675      if ( false !== $upload['error'] ) {
2676          return $upload;
2677      }
2678  
2679      /**
2680       * Filters whether to treat the upload bits as an error.
2681       *
2682       * Returning a non-array from the filter will effectively short-circuit preparing the upload bits
2683       * and return that value instead. An error message should be returned as a string.
2684       *
2685       * @since 3.0.0
2686       *
2687       * @param array|string $upload_bits_error An array of upload bits data, or error message to return.
2688       */
2689      $upload_bits_error = apply_filters(
2690          'wp_upload_bits',
2691          array(
2692              'name' => $name,
2693              'bits' => $bits,
2694              'time' => $time,
2695          )
2696      );
2697      if ( ! is_array( $upload_bits_error ) ) {
2698          $upload['error'] = $upload_bits_error;
2699          return $upload;
2700      }
2701  
2702      $filename = wp_unique_filename( $upload['path'], $name );
2703  
2704      $new_file = $upload['path'] . "/$filename";
2705      if ( ! wp_mkdir_p( dirname( $new_file ) ) ) {
2706          if ( 0 === strpos( $upload['basedir'], ABSPATH ) ) {
2707              $error_path = str_replace( ABSPATH, '', $upload['basedir'] ) . $upload['subdir'];
2708          } else {
2709              $error_path = wp_basename( $upload['basedir'] ) . $upload['subdir'];
2710          }
2711  
2712          $message = sprintf(
2713              /* translators: %s: Directory path. */
2714              __( 'Unable to create directory %s. Is its parent directory writable by the server?' ),
2715              $error_path
2716          );
2717          return array( 'error' => $message );
2718      }
2719  
2720      $ifp = @fopen( $new_file, 'wb' );
2721      if ( ! $ifp ) {
2722          return array(
2723              /* translators: %s: File name. */
2724              'error' => sprintf( __( 'Could not write file %s' ), $new_file ),
2725          );
2726      }
2727  
2728      fwrite( $ifp, $bits );
2729      fclose( $ifp );
2730      clearstatcache();
2731  
2732      // Set correct file permissions.
2733      $stat  = @ stat( dirname( $new_file ) );
2734      $perms = $stat['mode'] & 0007777;
2735      $perms = $perms & 0000666;
2736      chmod( $new_file, $perms );
2737      clearstatcache();
2738  
2739      // Compute the URL.
2740      $url = $upload['url'] . "/$filename";
2741  
2742      /** This filter is documented in wp-admin/includes/file.php */
2743      return apply_filters(
2744          'wp_handle_upload',
2745          array(
2746              'file'  => $new_file,
2747              'url'   => $url,
2748              'type'  => $wp_filetype['type'],
2749              'error' => false,
2750          ),
2751          'sideload'
2752      );
2753  }
2754  
2755  /**
2756   * Retrieve the file type based on the extension name.
2757   *
2758   * @since 2.5.0
2759   *
2760   * @param string $ext The extension to search.
2761   * @return string|void The file type, example: audio, video, document, spreadsheet, etc.
2762   */
2763  function wp_ext2type( $ext ) {
2764      $ext = strtolower( $ext );
2765  
2766      $ext2type = wp_get_ext_types();
2767      foreach ( $ext2type as $type => $exts ) {
2768          if ( in_array( $ext, $exts, true ) ) {
2769              return $type;
2770          }
2771      }
2772  }
2773  
2774  /**
2775   * Retrieve the file type from the file name.
2776   *
2777   * You can optionally define the mime array, if needed.
2778   *
2779   * @since 2.0.4
2780   *
2781   * @param string   $filename File name or path.
2782   * @param string[] $mimes    Optional. Array of mime types keyed by their file extension regex.
2783   * @return array {
2784   *     Values for the extension and mime type.
2785   *
2786   *     @type string|false $ext  File extension, or false if the file doesn't match a mime type.
2787   *     @type string|false $type File mime type, or false if the file doesn't match a mime type.
2788   * }
2789   */
2790  function wp_check_filetype( $filename, $mimes = null ) {
2791      if ( empty( $mimes ) ) {
2792          $mimes = get_allowed_mime_types();
2793      }
2794      $type = false;
2795      $ext  = false;
2796  
2797      foreach ( $mimes as $ext_preg => $mime_match ) {
2798          $ext_preg = '!\.(' . $ext_preg . ')$!i';
2799          if ( preg_match( $ext_preg, $filename, $ext_matches ) ) {
2800              $type = $mime_match;
2801              $ext  = $ext_matches[1];
2802              break;
2803          }
2804      }
2805  
2806      return compact( 'ext', 'type' );
2807  }
2808  
2809  /**
2810   * Attempt to determine the real file type of a file.
2811   *
2812   * If unable to, the file name extension will be used to determine type.
2813   *
2814   * If it's determined that the extension does not match the file's real type,
2815   * then the "proper_filename" value will be set with a proper filename and extension.
2816   *
2817   * Currently this function only supports renaming images validated via wp_get_image_mime().
2818   *
2819   * @since 3.0.0
2820   *
2821   * @param string   $file     Full path to the file.
2822   * @param string   $filename The name of the file (may differ from $file due to $file being
2823   *                           in a tmp directory).
2824   * @param string[] $mimes    Optional. Array of mime types keyed by their file extension regex.
2825   * @return array {
2826   *     Values for the extension, mime type, and corrected filename.
2827   *
2828   *     @type string|false $ext             File extension, or false if the file doesn't match a mime type.
2829   *     @type string|false $type            File mime type, or false if the file doesn't match a mime type.
2830   *     @type string|false $proper_filename File name with its correct extension, or false if it cannot be determined.
2831   * }
2832   */
2833  function wp_check_filetype_and_ext( $file, $filename, $mimes = null ) {
2834      $proper_filename = false;
2835  
2836      // Do basic extension validation and MIME mapping.
2837      $wp_filetype = wp_check_filetype( $filename, $mimes );
2838      $ext         = $wp_filetype['ext'];
2839      $type        = $wp_filetype['type'];
2840  
2841      // We can't do any further validation without a file to work with.
2842      if ( ! file_exists( $file ) ) {
2843          return compact( 'ext', 'type', 'proper_filename' );
2844      }
2845  
2846      $real_mime = false;
2847  
2848      // Validate image types.
2849      if ( $type && 0 === strpos( $type, 'image/' ) ) {
2850  
2851          // Attempt to figure out what type of image it actually is.
2852          $real_mime = wp_get_image_mime( $file );
2853  
2854          if ( $real_mime && $real_mime != $type ) {
2855              /**
2856               * Filters the list mapping image mime types to their respective extensions.
2857               *
2858               * @since 3.0.0
2859               *
2860               * @param array $mime_to_ext Array of image mime types and their matching extensions.
2861               */
2862              $mime_to_ext = apply_filters(
2863                  'getimagesize_mimes_to_exts',
2864                  array(
2865                      'image/jpeg' => 'jpg',
2866                      'image/png'  => 'png',
2867                      'image/gif'  => 'gif',
2868                      'image/bmp'  => 'bmp',
2869                      'image/tiff' => 'tif',
2870                  )
2871              );
2872  
2873              // Replace whatever is after the last period in the filename with the correct extension.
2874              if ( ! empty( $mime_to_ext[ $real_mime ] ) ) {
2875                  $filename_parts = explode( '.', $filename );
2876                  array_pop( $filename_parts );
2877                  $filename_parts[] = $mime_to_ext[ $real_mime ];
2878                  $new_filename     = implode( '.', $filename_parts );
2879  
2880                  if ( $new_filename != $filename ) {
2881                      $proper_filename = $new_filename; // Mark that it changed.
2882                  }
2883                  // Redefine the extension / MIME.
2884                  $wp_filetype = wp_check_filetype( $new_filename, $mimes );
2885                  $ext         = $wp_filetype['ext'];
2886                  $type        = $wp_filetype['type'];
2887              } else {
2888                  // Reset $real_mime and try validating again.
2889                  $real_mime = false;
2890              }
2891          }
2892      }
2893  
2894      // Validate files that didn't get validated during previous checks.
2895      if ( $type && ! $real_mime && extension_loaded( 'fileinfo' ) ) {
2896          $finfo     = finfo_open( FILEINFO_MIME_TYPE );
2897          $real_mime = finfo_file( $finfo, $file );
2898          finfo_close( $finfo );
2899  
2900          // fileinfo often misidentifies obscure files as one of these types.
2901          $nonspecific_types = array(
2902              'application/octet-stream',
2903              'application/encrypted',
2904              'application/CDFV2-encrypted',
2905              'application/zip',
2906          );
2907  
2908          /*
2909           * If $real_mime doesn't match the content type we're expecting from the file's extension,
2910           * we need to do some additional vetting. Media types and those listed in $nonspecific_types are
2911           * allowed some leeway, but anything else must exactly match the real content type.
2912           */
2913          if ( in_array( $real_mime, $nonspecific_types, true ) ) {
2914              // File is a non-specific binary type. That's ok if it's a type that generally tends to be binary.
2915              if ( ! in_array( substr( $type, 0, strcspn( $type, '/' ) ), array( 'application', 'video', 'audio' ), true ) ) {
2916                  $type = false;
2917                  $ext  = false;
2918              }
2919          } elseif ( 0 === strpos( $real_mime, 'video/' ) || 0 === strpos( $real_mime, 'audio/' ) ) {
2920              /*
2921               * For these types, only the major type must match the real value.
2922               * This means that common mismatches are forgiven: application/vnd.apple.numbers is often misidentified as application/zip,
2923               * and some media files are commonly named with the wrong extension (.mov instead of .mp4)
2924               */
2925              if ( substr( $real_mime, 0, strcspn( $real_mime, '/' ) ) !== substr( $type, 0, strcspn( $type, '/' ) ) ) {
2926                  $type = false;
2927                  $ext  = false;
2928              }
2929          } elseif ( 'text/plain' === $real_mime ) {
2930              // A few common file types are occasionally detected as text/plain; allow those.
2931              if ( ! in_array(
2932                  $type,
2933                  array(
2934                      'text/plain',
2935                      'text/csv',
2936                      'application/csv',
2937                      'text/richtext',
2938                      'text/tsv',
2939                      'text/vtt',
2940                  ),
2941                  true
2942              )
2943              ) {
2944                  $type = false;
2945                  $ext  = false;
2946              }
2947          } elseif ( 'application/csv' === $real_mime ) {
2948              // Special casing for CSV files.
2949              if ( ! in_array(
2950                  $type,
2951                  array(
2952                      'text/csv',
2953                      'text/plain',
2954                      'application/csv',
2955                  ),
2956                  true
2957              )
2958              ) {
2959                  $type = false;
2960                  $ext  = false;
2961              }
2962          } elseif ( 'text/rtf' === $real_mime ) {
2963              // Special casing for RTF files.
2964              if ( ! in_array(
2965                  $type,
2966                  array(
2967                      'text/rtf',
2968                      'text/plain',
2969                      'application/rtf',
2970                  ),
2971                  true
2972              )
2973              ) {
2974                  $type = false;
2975                  $ext  = false;
2976              }
2977          } else {
2978              if ( $type !== $real_mime ) {
2979                  /*
2980                   * Everything else including image/* and application/*:
2981                   * If the real content type doesn't match the file extension, assume it's dangerous.
2982                   */
2983                  $type = false;
2984                  $ext  = false;
2985              }
2986          }
2987      }
2988  
2989      // The mime type must be allowed.
2990      if ( $type ) {
2991          $allowed = get_allowed_mime_types();
2992  
2993          if ( ! in_array( $type, $allowed, true ) ) {
2994              $type = false;
2995              $ext  = false;
2996          }
2997      }
2998  
2999      /**
3000       * Filters the "real" file type of the given file.
3001       *
3002       * @since 3.0.0
3003       * @since 5.1.0 The $real_mime parameter was added.
3004       *
3005       * @param array       $wp_check_filetype_and_ext {
3006       *     Values for the extension, mime type, and corrected filename.
3007       *
3008       *     @type string|false $ext             File extension, or false if the file doesn't match a mime type.
3009       *     @type string|false $type            File mime type, or false if the file doesn't match a mime type.
3010       *     @type string|false $proper_filename File name with its correct extension, or false if it cannot be determined.
3011       * }
3012       * @param string      $file                      Full path to the file.
3013       * @param string      $filename                  The name of the file (may differ from $file due to
3014       *                                               $file being in a tmp directory).
3015       * @param string[]    $mimes                     Array of mime types keyed by their file extension regex.
3016       * @param string|bool $real_mime                 The actual mime type or false if the type cannot be determined.
3017       */
3018      return apply_filters( 'wp_check_filetype_and_ext', compact( 'ext', 'type', 'proper_filename' ), $file, $filename, $mimes, $real_mime );
3019  }
3020  
3021  /**
3022   * Returns the real mime type of an image file.
3023   *
3024   * This depends on exif_imagetype() or getimagesize() to determine real mime types.
3025   *
3026   * @since 4.7.1
3027   *
3028   * @param string $file Full path to the file.
3029   * @return string|false The actual mime type or false if the type cannot be determined.
3030   */
3031  function wp_get_image_mime( $file ) {
3032      /*
3033       * Use exif_imagetype() to check the mimetype if available or fall back to
3034       * getimagesize() if exif isn't avaialbe. If either function throws an Exception
3035       * we assume the file could not be validated.
3036       */
3037      try {
3038          if ( is_callable( 'exif_imagetype' ) ) {
3039              $imagetype = exif_imagetype( $file );
3040              $mime      = ( $imagetype ) ? image_type_to_mime_type( $imagetype ) : false;
3041          } elseif ( function_exists( 'getimagesize' ) ) {
3042              $imagesize = @getimagesize( $file );
3043              $mime      = ( isset( $imagesize['mime'] ) ) ? $imagesize['mime'] : false;
3044          } else {
3045              $mime = false;
3046          }
3047      } catch ( Exception $e ) {
3048          $mime = false;
3049      }
3050  
3051      return $mime;
3052  }
3053  
3054  /**
3055   * Retrieve list of mime types and file extensions.
3056   *
3057   * @since 3.5.0
3058   * @since 4.2.0 Support was added for GIMP (.xcf) files.
3059   * @since 4.9.2 Support was added for Flac (.flac) files.
3060   * @since 4.9.6 Support was added for AAC (.aac) files.
3061   *
3062   * @return string[] Array of mime types keyed by the file extension regex corresponding to those types.
3063   */
3064  function wp_get_mime_types() {
3065      /**
3066       * Filters the list of mime types and file extensions.
3067       *
3068       * This filter should be used to add, not remove, mime types. To remove
3069       * mime types, use the {@see 'upload_mimes'} filter.
3070       *
3071       * @since 3.5.0
3072       *
3073       * @param string[] $wp_get_mime_types Mime types keyed by the file extension regex
3074       *                                 corresponding to those types.
3075       */
3076      return apply_filters(
3077          'mime_types',
3078          array(
3079              // Image formats.
3080              'jpg|jpeg|jpe'                 => 'image/jpeg',
3081              'gif'                          => 'image/gif',
3082              'png'                          => 'image/png',
3083              'bmp'                          => 'image/bmp',
3084              'tiff|tif'                     => 'image/tiff',
3085              'ico'                          => 'image/x-icon',
3086              'heic'                         => 'image/heic',
3087              // Video formats.
3088              'asf|asx'                      => 'video/x-ms-asf',
3089              'wmv'                          => 'video/x-ms-wmv',
3090              'wmx'                          => 'video/x-ms-wmx',
3091              'wm'                           => 'video/x-ms-wm',
3092              'avi'                          => 'video/avi',
3093              'divx'                         => 'video/divx',
3094              'flv'                          => 'video/x-flv',
3095              'mov|qt'                       => 'video/quicktime',
3096              'mpeg|mpg|mpe'                 => 'video/mpeg',
3097              'mp4|m4v'                      => 'video/mp4',
3098              'ogv'                          => 'video/ogg',
3099              'webm'                         => 'video/webm',
3100              'mkv'                          => 'video/x-matroska',
3101              '3gp|3gpp'                     => 'video/3gpp',  // Can also be audio.
3102              '3g2|3gp2'                     => 'video/3gpp2', // Can also be audio.
3103              // Text formats.
3104              'txt|asc|c|cc|h|srt'           => 'text/plain',
3105              'csv'                          => 'text/csv',
3106              'tsv'                          => 'text/tab-separated-values',
3107              'ics'                          => 'text/calendar',
3108              'rtx'                          => 'text/richtext',
3109              'css'                          => 'text/css',
3110              'htm|html'                     => 'text/html',
3111              'vtt'                          => 'text/vtt',
3112              'dfxp'                         => 'application/ttaf+xml',
3113              // Audio formats.
3114              'mp3|m4a|m4b'                  => 'audio/mpeg',
3115              'aac'                          => 'audio/aac',
3116              'ra|ram'                       => 'audio/x-realaudio',
3117              'wav'                          => 'audio/wav',
3118              'ogg|oga'                      => 'audio/ogg',
3119              'flac'                         => 'audio/flac',
3120              'mid|midi'                     => 'audio/midi',
3121              'wma'                          => 'audio/x-ms-wma',
3122              'wax'                          => 'audio/x-ms-wax',
3123              'mka'                          => 'audio/x-matroska',
3124              // Misc application formats.
3125              'rtf'                          => 'application/rtf',
3126              'js'                           => 'application/javascript',
3127              'pdf'                          => 'application/pdf',
3128              'swf'                          => 'application/x-shockwave-flash',
3129              'class'                        => 'application/java',
3130              'tar'                          => 'application/x-tar',
3131              'zip'                          => 'application/zip',
3132              'gz|gzip'                      => 'application/x-gzip',
3133              'rar'                          => 'application/rar',
3134              '7z'                           => 'application/x-7z-compressed',
3135              'exe'                          => 'application/x-msdownload',
3136              'psd'                          => 'application/octet-stream',
3137              'xcf'                          => 'application/octet-stream',
3138              // MS Office formats.
3139              'doc'                          => 'application/msword',
3140              'pot|pps|ppt'                  => 'application/vnd.ms-powerpoint',
3141              'wri'                          => 'application/vnd.ms-write',
3142              'xla|xls|xlt|xlw'              => 'application/vnd.ms-excel',
3143              'mdb'                          => 'application/vnd.ms-access',
3144              'mpp'                          => 'application/vnd.ms-project',
3145              'docx'                         => 'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
3146              'docm'                         => 'application/vnd.ms-word.document.macroEnabled.12',
3147              'dotx'                         => 'application/vnd.openxmlformats-officedocument.wordprocessingml.template',
3148              'dotm'                         => 'application/vnd.ms-word.template.macroEnabled.12',
3149              'xlsx'                         => 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
3150              'xlsm'                         => 'application/vnd.ms-excel.sheet.macroEnabled.12',
3151              'xlsb'                         => 'application/vnd.ms-excel.sheet.binary.macroEnabled.12',
3152              'xltx'                         => 'application/vnd.openxmlformats-officedocument.spreadsheetml.template',
3153              'xltm'                         => 'application/vnd.ms-excel.template.macroEnabled.12',
3154              'xlam'                         => 'application/vnd.ms-excel.addin.macroEnabled.12',
3155              'pptx'                         => 'application/vnd.openxmlformats-officedocument.presentationml.presentation',
3156              'pptm'                         => 'application/vnd.ms-powerpoint.presentation.macroEnabled.12',
3157              'ppsx'                         => 'application/vnd.openxmlformats-officedocument.presentationml.slideshow',
3158              'ppsm'                         => 'application/vnd.ms-powerpoint.slideshow.macroEnabled.12',
3159              'potx'                         => 'application/vnd.openxmlformats-officedocument.presentationml.template',
3160              'potm'                         => 'application/vnd.ms-powerpoint.template.macroEnabled.12',
3161              'ppam'                         => 'application/vnd.ms-powerpoint.addin.macroEnabled.12',
3162              'sldx'                         => 'application/vnd.openxmlformats-officedocument.presentationml.slide',
3163              'sldm'                         => 'application/vnd.ms-powerpoint.slide.macroEnabled.12',
3164              'onetoc|onetoc2|onetmp|onepkg' => 'application/onenote',
3165              'oxps'                         => 'application/oxps',
3166              'xps'                          => 'application/vnd.ms-xpsdocument',
3167              // OpenOffice formats.
3168              'odt'                          => 'application/vnd.oasis.opendocument.text',
3169              'odp'                          => 'application/vnd.oasis.opendocument.presentation',
3170              'ods'                          => 'application/vnd.oasis.opendocument.spreadsheet',
3171              'odg'                          => 'application/vnd.oasis.opendocument.graphics',
3172              'odc'                          => 'application/vnd.oasis.opendocument.chart',
3173              'odb'                          => 'application/vnd.oasis.opendocument.database',
3174              'odf'                          => 'application/vnd.oasis.opendocument.formula',
3175              // WordPerfect formats.
3176              'wp|wpd'                       => 'application/wordperfect',
3177              // iWork formats.
3178              'key'                          => 'application/vnd.apple.keynote',
3179              'numbers'                      => 'application/vnd.apple.numbers',
3180              'pages'                        => 'application/vnd.apple.pages',
3181          )
3182      );
3183  }
3184  
3185  /**
3186   * Retrieves the list of common file extensions and their types.
3187   *
3188   * @since 4.6.0
3189   *
3190   * @return array[] Multi-dimensional array of file extensions types keyed by the type of file.
3191   */
3192  function wp_get_ext_types() {
3193  
3194      /**
3195       * Filters file type based on the extension name.
3196       *
3197       * @since 2.5.0
3198       *
3199       * @see wp_ext2type()
3200       *
3201       * @param array[] $ext2type Multi-dimensional array of file extensions types keyed by the type of file.
3202       */
3203      return apply_filters(
3204          'ext2type',
3205          array(
3206              'image'       => array( 'jpg', 'jpeg', 'jpe', 'gif', 'png', 'bmp', 'tif', 'tiff', 'ico', 'heic' ),
3207              'audio'       => array( 'aac', 'ac3', 'aif', 'aiff', 'flac', 'm3a', 'm4a', 'm4b', 'mka', 'mp1', 'mp2', 'mp3', 'ogg', 'oga', 'ram', 'wav', 'wma' ),
3208              'video'       => array( '3g2', '3gp', '3gpp', 'asf', 'avi', 'divx', 'dv', 'flv', 'm4v', 'mkv', 'mov', 'mp4', 'mpeg', 'mpg', 'mpv', 'ogm', 'ogv', 'qt', 'rm', 'vob', 'wmv' ),
3209              'document'    => array( 'doc', 'docx', 'docm', 'dotm', 'odt', 'pages', 'pdf', 'xps', 'oxps', 'rtf', 'wp', 'wpd', 'psd', 'xcf' ),
3210              'spreadsheet' => array( 'numbers', 'ods', 'xls', 'xlsx', 'xlsm', 'xlsb' ),
3211              'interactive' => array( 'swf', 'key', 'ppt', 'pptx', 'pptm', 'pps', 'ppsx', 'ppsm', 'sldx', 'sldm', 'odp' ),
3212              'text'        => array( 'asc', 'csv', 'tsv', 'txt' ),
3213              'archive'     => array( 'bz2', 'cab', 'dmg', 'gz', 'rar', 'sea', 'sit', 'sqx', 'tar', 'tgz', 'zip', '7z' ),
3214              'code'        => array( 'css', 'htm', 'html', 'php', 'js' ),
3215          )
3216      );
3217  }
3218  
3219  /**
3220   * Retrieve list of allowed mime types and file extensions.
3221   *
3222   * @since 2.8.6
3223   *
3224   * @param int|WP_User $user Optional. User to check. Defaults to current user.
3225   * @return string[] Array of mime types keyed by the file extension regex corresponding
3226   *                  to those types.
3227   */
3228  function get_allowed_mime_types( $user = null ) {
3229      $t = wp_get_mime_types();
3230  
3231      unset( $t['swf'], $t['exe'] );
3232      if ( function_exists( 'current_user_can' ) ) {
3233          $unfiltered = $user ? user_can( $user, 'unfiltered_html' ) : current_user_can( 'unfiltered_html' );
3234      }
3235  
3236      if ( empty( $unfiltered ) ) {
3237          unset( $t['htm|html'], $t['js'] );
3238      }
3239  
3240      /**
3241       * Filters list of allowed mime types and file extensions.
3242       *
3243       * @since 2.0.0
3244       *
3245       * @param array            $t    Mime types keyed by the file extension regex corresponding to those types.
3246       * @param int|WP_User|null $user User ID, User object or null if not provided (indicates current user).
3247       */
3248      return apply_filters( 'upload_mimes', $t, $user );
3249  }
3250  
3251  /**
3252   * Display "Are You Sure" message to confirm the action being taken.
3253   *
3254   * If the action has the nonce explain message, then it will be displayed
3255   * along with the "Are you sure?" message.
3256   *
3257   * @since 2.0.4
3258   *
3259   * @param string $action The nonce action.
3260   */
3261  function wp_nonce_ays( $action ) {
3262      if ( 'log-out' === $action ) {
3263          $html = sprintf(
3264              /* translators: %s: Site title. */
3265              __( 'You are attempting to log out of %s' ),
3266              get_bloginfo( 'name' )
3267          );
3268          $html       .= '</p><p>';
3269          $redirect_to = isset( $_REQUEST['redirect_to'] ) ? $_REQUEST['redirect_to'] : '';
3270          $html       .= sprintf(
3271              /* translators: %s: Logout URL. */
3272              __( 'Do you really want to <a href="%s">log out</a>?' ),
3273              wp_logout_url( $redirect_to )
3274          );
3275      } else {
3276          $html = __( 'The link you followed has expired.' );
3277          if ( wp_get_referer() ) {
3278              $html .= '</p><p>';
3279              $html .= sprintf(
3280                  '<a href="%s">%s</a>',
3281                  esc_url( remove_query_arg( 'updated', wp_get_referer() ) ),
3282                  __( 'Please try again.' )
3283              );
3284          }
3285      }
3286  
3287      wp_die( $html, __( 'Something went wrong.' ), 403 );
3288  }
3289  
3290  /**
3291   * Kills WordPress execution and displays HTML page with an error message.
3292   *
3293   * This function complements the `die()` PHP function. The difference is that
3294   * HTML will be displayed to the user. It is recommended to use this function
3295   * only when the execution should not continue any further. It is not recommended
3296   * to call this function very often, and try to handle as many errors as possible
3297   * silently or more gracefully.
3298   *
3299   * As a shorthand, the desired HTTP response code may be passed as an integer to
3300   * the `$title` parameter (the default title would apply) or the `$args` parameter.
3301   *
3302   * @since 2.0.4
3303   * @since 4.1.0 The `$title` and `$args` parameters were changed to optionally accept
3304   *              an integer to be used as the response code.
3305   * @since 5.1.0 The `$link_url`, `$link_text`, and `$exit` arguments were added.
3306   * @since 5.3.0 The `$charset` argument was added.
3307   * @since 5.5.0 The `$text_direction` argument has a priority over get_language_attributes()
3308   *              in the default handler.
3309   *
3310   * @global WP_Query $wp_query WordPress Query object.
3311   *
3312   * @param string|WP_Error  $message Optional. Error message. If this is a WP_Error object,
3313   *                                  and not an Ajax or XML-RPC request, the error's messages are used.
3314   *                                  Default empty.
3315   * @param string|int       $title   Optional. Error title. If `$message` is a `WP_Error` object,
3316   *                                  error data with the key 'title' may be used to specify the title.
3317   *                                  If `$title` is an integer, then it is treated as the response
3318   *                                  code. Default empty.
3319   * @param string|array|int $args {
3320   *     Optional. Arguments to control behavior. If `$args` is an integer, then it is treated
3321   *     as the response code. Default empty array.
3322   *
3323   *     @type int    $response       The HTTP response code. Default 200 for Ajax requests, 500 otherwise.
3324   *     @type string $link_url       A URL to include a link to. Only works in combination with $link_text.
3325   *                                  Default empty string.
3326   *     @type string $link_text      A label for the link to include. Only works in combination with $link_url.
3327   *                                  Default empty string.
3328   *     @type bool   $back_link      Whether to include a link to go back. Default false.
3329   *     @type string $text_direction The text direction. This is only useful internally, when WordPress is still
3330   *                                  loading and the site's locale is not set up yet. Accepts 'rtl' and 'ltr'.
3331   *                                  Default is the value of is_rtl().
3332   *     @type string $charset        Character set of the HTML output. Default 'utf-8'.
3333   *     @type string $code           Error code to use. Default is 'wp_die', or the main error code if $message
3334   *                                  is a WP_Error.
3335   *     @type bool   $exit           Whether to exit the process after completion. Default true.
3336   * }
3337   */
3338  function wp_die( $message = '', $title = '', $args = array() ) {
3339      global $wp_query;
3340  
3341      if ( is_int( $args ) ) {
3342          $args = array( 'response' => $args );
3343      } elseif ( is_int( $title ) ) {
3344          $args  = array( 'response' => $title );
3345          $title = '';
3346      }
3347  
3348      if ( wp_doing_ajax() ) {
3349          /**
3350           * Filters the callback for killing WordPress execution for Ajax requests.
3351           *
3352           * @since 3.4.0
3353           *
3354           * @param callable $function Callback function name.
3355           */
3356          $function = apply_filters( 'wp_die_ajax_handler', '_ajax_wp_die_handler' );
3357      } elseif ( wp_is_json_request() ) {
3358          /**
3359           * Filters the callback for killing WordPress execution for JSON requests.
3360           *
3361           * @since 5.1.0
3362           *
3363           * @param callable $function Callback function name.
3364           */
3365          $function = apply_filters( 'wp_die_json_handler', '_json_wp_die_handler' );
3366      } elseif ( wp_is_jsonp_request() ) {
3367          /**
3368           * Filters the callback for killing WordPress execution for JSONP requests.
3369           *
3370           * @since 5.2.0
3371           *
3372           * @param callable $function Callback function name.
3373           */
3374          $function = apply_filters( 'wp_die_jsonp_handler', '_jsonp_wp_die_handler' );
3375      } elseif ( defined( 'XMLRPC_REQUEST' ) && XMLRPC_REQUEST ) {
3376          /**
3377           * Filters the callback for killing WordPress execution for XML-RPC requests.
3378           *
3379           * @since 3.4.0
3380           *
3381           * @param callable $function Callback function name.
3382           */
3383          $function = apply_filters( 'wp_die_xmlrpc_handler', '_xmlrpc_wp_die_handler' );
3384      } elseif ( wp_is_xml_request()
3385          || isset( $wp_query ) &&
3386              ( function_exists( 'is_feed' ) && is_feed()
3387              || function_exists( 'is_comment_feed' ) && is_comment_feed()
3388              || function_exists( 'is_trackback' ) && is_trackback() ) ) {
3389          /**
3390           * Filters the callback for killing WordPress execution for XML requests.
3391           *
3392           * @since 5.2.0
3393           *
3394           * @param callable $function Callback function name.
3395           */
3396          $function = apply_filters( 'wp_die_xml_handler', '_xml_wp_die_handler' );
3397      } else {
3398          /**
3399           * Filters the callback for killing WordPress execution for all non-Ajax, non-JSON, non-XML requests.
3400           *
3401           * @since 3.0.0
3402           *
3403           * @param callable $function Callback function name.
3404           */
3405          $function = apply_filters( 'wp_die_handler', '_default_wp_die_handler' );
3406      }
3407  
3408      call_user_func( $function, $message, $title, $args );
3409  }
3410  
3411  /**
3412   * Kills WordPress execution and displays HTML page with an error message.
3413   *
3414   * This is the default handler for wp_die(). If you want a custom one,
3415   * you can override this using the {@see 'wp_die_handler'} filter in wp_die().
3416   *
3417   * @since 3.0.0
3418   * @access private
3419   *
3420   * @param string|WP_Error $message Error message or WP_Error object.
3421   * @param string          $title   Optional. Error title. Default empty.
3422   * @param string|array    $args    Optional. Arguments to control behavior. Default empty array.
3423   */
3424  function _default_wp_die_handler( $message, $title = '', $args = array() ) {
3425      list( $message, $title, $parsed_args ) = _wp_die_process_input( $message, $title, $args );
3426  
3427      if ( is_string( $message ) ) {
3428          if ( ! empty( $parsed_args['additional_errors'] ) ) {
3429              $message = array_merge(
3430                  array( $message ),
3431                  wp_list_pluck( $parsed_args['additional_errors'], 'message' )
3432              );
3433              $message = "<ul>\n\t\t<li>" . join( "</li>\n\t\t<li>", $message ) . "</li>\n\t</ul>";
3434          }
3435  
3436          $message = sprintf(
3437              '<div class="wp-die-message">%s</div>',
3438              $message
3439          );
3440      }
3441  
3442      $have_gettext = function_exists( '__' );
3443  
3444      if ( ! empty( $parsed_args['link_url'] ) && ! empty( $parsed_args['link_text'] ) ) {
3445          $link_url = $parsed_args['link_url'];
3446          if ( function_exists( 'esc_url' ) ) {
3447              $link_url = esc_url( $link_url );
3448          }
3449          $link_text = $parsed_args['link_text'];
3450          $message  .= "\n<p><a href='{$link_url}'>{$link_text}</a></p>";
3451      }
3452  
3453      if ( isset( $parsed_args['back_link'] ) && $parsed_args['back_link'] ) {
3454          $back_text = $have_gettext ? __( '&laquo; Back' ) : '&laquo; Back';
3455          $message  .= "\n<p><a href='javascript:history.back()'>$back_text</a></p>";
3456      }
3457  
3458      if ( ! did_action( 'admin_head' ) ) :
3459          if ( ! headers_sent() ) {
3460              header( "Content-Type: text/html; charset={$parsed_args['charset']}" );
3461              status_header( $parsed_args['response'] );
3462              nocache_headers();
3463          }
3464  
3465          $text_direction = $parsed_args['text_direction'];
3466          $dir_attr       = "dir='$text_direction'";
3467  
3468          // If `text_direction` was not explicitly passed,
3469          // use get_language_attributes() if available.
3470          if ( empty( $args['text_direction'] )
3471              && function_exists( 'language_attributes' ) && function_exists( 'is_rtl' )
3472          ) {
3473              $dir_attr = get_language_attributes();
3474          }
3475          ?>
3476  <!DOCTYPE html>
3477  <html <?php echo $dir_attr; ?>>
3478  <head>
3479      <meta http-equiv="Content-Type" content="text/html; charset=<?php echo $parsed_args['charset']; ?>" />
3480      <meta name="viewport" content="width=device-width">
3481          <?php
3482          if ( function_exists( 'wp_no_robots' ) ) {
3483              wp_no_robots();
3484          }
3485          ?>
3486      <title><?php echo $title; ?></title>
3487      <style type="text/css">
3488          html {
3489              background: #f1f1f1;
3490          }
3491          body {
3492              background: #fff;
3493              color: #444;
3494              font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
3495              margin: 2em auto;
3496              padding: 1em 2em;
3497              max-width: 700px;
3498              -webkit-box-shadow: 0 1px 3px rgba(0, 0, 0, 0.13);
3499              box-shadow: 0 1px 3px rgba(0, 0, 0, 0.13);
3500          }
3501          h1 {
3502              border-bottom: 1px solid #dadada;
3503              clear: both;
3504              color: #666;
3505              font-size: 24px;
3506              margin: 30px 0 0 0;
3507              padding: 0;
3508              padding-bottom: 7px;
3509          }
3510          #error-page {
3511              margin-top: 50px;
3512          }
3513          #error-page p,
3514          #error-page .wp-die-message {
3515              font-size: 14px;
3516              line-height: 1.5;
3517              margin: 25px 0 20px;
3518          }
3519          #error-page code {
3520              font-family: Consolas, Monaco, monospace;
3521          }
3522          ul li {
3523              margin-bottom: 10px;
3524              font-size: 14px ;
3525          }
3526          a {
3527              color: #0073aa;
3528          }
3529          a:hover,
3530          a:active {
3531              color: #006799;
3532          }
3533          a:focus {
3534              color: #124964;
3535              -webkit-box-shadow:
3536                  0 0 0 1px #5b9dd9,
3537                  0 0 2px 1px rgba(30, 140, 190, 0.8);
3538              box-shadow:
3539                  0 0 0 1px #5b9dd9,
3540                  0 0 2px 1px rgba(30, 140, 190, 0.8);
3541              outline: none;
3542          }
3543          .button {
3544              background: #f7f7f7;
3545              border: 1px solid #ccc;
3546              color: #555;
3547              display: inline-block;
3548              text-decoration: none;
3549              font-size: 13px;
3550              line-height: 2;
3551              height: 28px;
3552              margin: 0;
3553              padding: 0 10px 1px;
3554              cursor: pointer;
3555              -webkit-border-radius: 3px;
3556              -webkit-appearance: none;
3557              border-radius: 3px;
3558              white-space: nowrap;
3559              -webkit-box-sizing: border-box;
3560              -moz-box-sizing:    border-box;
3561              box-sizing:         border-box;
3562  
3563              -webkit-box-shadow: 0 1px 0 #ccc;
3564              box-shadow: 0 1px 0 #ccc;
3565              vertical-align: top;
3566          }
3567  
3568          .button.button-large {
3569              height: 30px;
3570              line-height: 2.15384615;
3571              padding: 0 12px 2px;
3572          }
3573  
3574          .button:hover,
3575          .button:focus {
3576              background: #fafafa;
3577              border-color: #999;
3578              color: #23282d;
3579          }
3580  
3581          .button:focus {
3582              border-color: #5b9dd9;
3583              -webkit-box-shadow: 0 0 3px rgba(0, 115, 170, 0.8);
3584              box-shadow: 0 0 3px rgba(0, 115, 170, 0.8);
3585              outline: none;
3586          }
3587  
3588          .button:active {
3589              background: #eee;
3590              border-color: #999;
3591              -webkit-box-shadow: inset 0 2px 5px -3px rgba(0, 0, 0, 0.5);
3592              box-shadow: inset 0 2px 5px -3px rgba(0, 0, 0, 0.5);
3593          }
3594  
3595          <?php
3596          if ( 'rtl' === $text_direction ) {
3597              echo 'body { font-family: Tahoma, Arial; }';
3598          }
3599          ?>
3600      </style>
3601  </head>
3602  <body id="error-page">
3603  <?php endif; // ! did_action( 'admin_head' ) ?>
3604      <?php echo $message; ?>
3605  </body>
3606  </html>
3607      <?php
3608      if ( $parsed_args['exit'] ) {
3609          die();
3610      }
3611  }
3612  
3613  /**
3614   * Kills WordPress execution and displays Ajax response with an error message.
3615   *
3616   * This is the handler for wp_die() when processing Ajax requests.
3617   *
3618   * @since 3.4.0
3619   * @access private
3620   *
3621   * @param string       $message Error message.
3622   * @param string       $title   Optional. Error title (unused). Default empty.
3623   * @param string|array $args    Optional. Arguments to control behavior. Default empty array.
3624   */
3625  function _ajax_wp_die_handler( $message, $title = '', $args = array() ) {
3626      // Set default 'response' to 200 for Ajax requests.
3627      $args = wp_parse_args(
3628          $args,
3629          array( 'response' => 200 )
3630      );
3631  
3632      list( $message, $title, $parsed_args ) = _wp_die_process_input( $message, $title, $args );
3633  
3634      if ( ! headers_sent() ) {
3635          // This is intentional. For backward-compatibility, support passing null here.
3636          if ( null !== $args['response'] ) {
3637              status_header( $parsed_args['response'] );
3638          }
3639          nocache_headers();
3640      }
3641  
3642      if ( is_scalar( $message ) ) {
3643          $message = (string) $message;
3644      } else {
3645          $message = '0';
3646      }
3647  
3648      if ( $parsed_args['exit'] ) {
3649          die( $message );
3650      }
3651  
3652      echo $message;
3653  }
3654  
3655  /**
3656   * Kills WordPress execution and displays JSON response with an error message.
3657   *
3658   * This is the handler for wp_die() when processing JSON requests.
3659   *
3660   * @since 5.1.0
3661   * @access private
3662   *
3663   * @param string       $message Error message.
3664   * @param string       $title   Optional. Error title. Default empty.
3665   * @param string|array $args    Optional. Arguments to control behavior. Default empty array.
3666   */
3667  function _json_wp_die_handler( $message, $title = '', $args = array() ) {
3668      list( $message, $title, $parsed_args ) = _wp_die_process_input( $message, $title, $args );
3669  
3670      $data = array(
3671          'code'              => $parsed_args['code'],
3672          'message'           => $message,
3673          'data'              => array(
3674              'status' => $parsed_args['response'],
3675          ),
3676          'additional_errors' => $parsed_args['additional_errors'],
3677      );
3678  
3679      if ( ! headers_sent() ) {
3680          header( "Content-Type: application/json; charset={$parsed_args['charset']}" );
3681          if ( null !== $parsed_args['response'] ) {
3682              status_header( $parsed_args['response'] );
3683          }
3684          nocache_headers();
3685      }
3686  
3687      echo wp_json_encode( $data );
3688      if ( $parsed_args['exit'] ) {
3689          die();
3690      }
3691  }
3692  
3693  /**
3694   * Kills WordPress execution and displays JSONP response with an error message.
3695   *
3696   * This is the handler for wp_die() when processing JSONP requests.
3697   *
3698   * @since 5.2.0
3699   * @access private
3700   *
3701   * @param string       $message Error message.
3702   * @param string       $title   Optional. Error title. Default empty.
3703   * @param string|array $args    Optional. Arguments to control behavior. Default empty array.
3704   */
3705  function _jsonp_wp_die_handler( $message, $title = '', $args = array() ) {
3706      list( $message, $title, $parsed_args ) = _wp_die_process_input( $message, $title, $args );
3707  
3708      $data = array(
3709          'code'              => $parsed_args['code'],
3710          'message'           => $message,
3711          'data'              => array(
3712              'status' => $parsed_args['response'],
3713          ),
3714          'additional_errors' => $parsed_args['additional_errors'],
3715      );
3716  
3717      if ( ! headers_sent() ) {
3718          header( "Content-Type: application/javascript; charset={$parsed_args['charset']}" );
3719          header( 'X-Content-Type-Options: nosniff' );
3720          header( 'X-Robots-Tag: noindex' );
3721          if ( null !== $parsed_args['response'] ) {
3722              status_header( $parsed_args['response'] );
3723          }
3724          nocache_headers();
3725      }
3726  
3727      $result         = wp_json_encode( $data );
3728      $jsonp_callback = $_GET['_jsonp'];
3729      echo '/**/' . $jsonp_callback . '(' . $result . ')';
3730      if ( $parsed_args['exit'] ) {
3731          die();
3732      }
3733  }
3734  
3735  /**
3736   * Kills WordPress execution and displays XML response with an error message.
3737   *
3738   * This is the handler for wp_die() when processing XMLRPC requests.
3739   *
3740   * @since 3.2.0
3741   * @access private
3742   *
3743   * @global wp_xmlrpc_server $wp_xmlrpc_server
3744   *
3745   * @param string       $message Error message.
3746   * @param string       $title   Optional. Error title. Default empty.
3747   * @param string|array $args    Optional. Arguments to control behavior. Default empty array.
3748   */
3749  function _xmlrpc_wp_die_handler( $message, $title = '', $args = array() ) {
3750      global $wp_xmlrpc_server;
3751  
3752      list( $message, $title, $parsed_args ) = _wp_die_process_input( $message, $title, $args );
3753  
3754      if ( ! headers_sent() ) {
3755          nocache_headers();
3756      }
3757  
3758      if ( $wp_xmlrpc_server ) {
3759          $error = new IXR_Error( $parsed_args['response'], $message );
3760          $wp_xmlrpc_server->output( $error->getXml() );
3761      }
3762      if ( $parsed_args['exit'] ) {
3763          die();
3764      }
3765  }
3766  
3767  /**
3768   * Kills WordPress execution and displays XML response with an error message.
3769   *
3770   * This is the handler for wp_die() when processing XML requests.
3771   *
3772   * @since 5.2.0
3773   * @access private
3774   *
3775   * @param string       $message Error message.
3776   * @param string       $title   Optional. Error title. Default empty.
3777   * @param string|array $args    Optional. Arguments to control behavior. Default empty array.
3778   */
3779  function _xml_wp_die_handler( $message, $title = '', $args = array() ) {
3780      list( $message, $title, $parsed_args ) = _wp_die_process_input( $message, $title, $args );
3781  
3782      $message = htmlspecialchars( $message );
3783      $title   = htmlspecialchars( $title );
3784  
3785      $xml = <<<EOD
3786  <error>
3787      <code>{$parsed_args['code']}</code>
3788      <title><![CDATA[{$title}]]></title>
3789      <message><![CDATA[{$message}]]></message>
3790      <data>
3791          <status>{$parsed_args['response']}</status>
3792      </data>
3793  </error>
3794  
3795  EOD;
3796  
3797      if ( ! headers_sent() ) {
3798          header( "Content-Type: text/xml; charset={$parsed_args['charset']}" );
3799          if ( null !== $parsed_args['response'] ) {
3800              status_header( $parsed_args['response'] );
3801          }
3802          nocache_headers();
3803      }
3804  
3805      echo $xml;
3806      if ( $parsed_args['exit'] ) {
3807          die();
3808      }
3809  }
3810  
3811  /**
3812   * Kills WordPress execution and displays an error message.
3813   *
3814   * This is the handler for wp_die() when processing APP requests.
3815   *
3816   * @since 3.4.0
3817   * @since 5.1.0 Added the $title and $args parameters.
3818   * @access private
3819   *
3820   * @param string       $message Optional. Response to print. Default empty.
3821   * @param string       $title   Optional. Error title (unused). Default empty.
3822   * @param string|array $args    Optional. Arguments to control behavior. Default empty array.
3823   */
3824  function _scalar_wp_die_handler( $message = '', $title = '', $args = array() ) {
3825      list( $message, $title, $parsed_args ) = _wp_die_process_input( $message, $title, $args );
3826  
3827      if ( $parsed_args['exit'] ) {
3828          if ( is_scalar( $message ) ) {
3829              die( (string) $message );
3830          }
3831          die();
3832      }
3833  
3834      if ( is_scalar( $message ) ) {
3835          echo (string) $message;
3836      }
3837  }
3838  
3839  /**
3840   * Processes arguments passed to wp_die() consistently for its handlers.
3841   *
3842   * @since 5.1.0
3843   * @access private
3844   *
3845   * @param string|WP_Error $message Error message or WP_Error object.
3846   * @param string          $title   Optional. Error title. Default empty.
3847   * @param string|array    $args    Optional. Arguments to control behavior. Default empty array.
3848   * @return array {
3849   *     Processed arguments.
3850   *
3851   *     @type string $0 Error message.
3852   *     @type string $1 Error title.
3853   *     @type array  $2 Arguments to control behavior.
3854   * }
3855   */
3856  function _wp_die_process_input( $message, $title = '', $args = array() ) {
3857      $defaults = array(
3858          'response'          => 0,
3859          'code'              => '',
3860          'exit'              => true,
3861          'back_link'         => false,
3862          'link_url'          => '',
3863          'link_text'         => '',
3864          'text_direction'    => '',
3865          'charset'           => 'utf-8',
3866          'additional_errors' => array(),
3867      );
3868  
3869      $args = wp_parse_args( $args, $defaults );
3870  
3871      if ( function_exists( 'is_wp_error' ) && is_wp_error( $message ) ) {
3872          if ( ! empty( $message->errors ) ) {
3873              $errors = array();
3874              foreach ( (array) $message->errors as $error_code => $error_messages ) {
3875                  foreach ( (array) $error_messages as $error_message ) {
3876                      $errors[] = array(
3877                          'code'    => $error_code,
3878                          'message' => $error_message,
3879                          'data'    => $message->get_error_data( $error_code ),
3880                      );
3881                  }
3882              }
3883  
3884              $message = $errors[0]['message'];
3885              if ( empty( $args['code'] ) ) {
3886                  $args['code'] = $errors[0]['code'];
3887              }
3888              if ( empty( $args['response'] ) && is_array( $errors[0]['data'] ) && ! empty( $errors[0]['data']['status'] ) ) {
3889                  $args['response'] = $errors[0]['data']['status'];
3890              }
3891              if ( empty( $title ) && is_array( $errors[0]['data'] ) && ! empty( $errors[0]['data']['title'] ) ) {
3892                  $title = $errors[0]['data']['title'];
3893              }
3894  
3895              unset( $errors[0] );
3896              $args['additional_errors'] = array_values( $errors );
3897          } else {
3898              $message = '';
3899          }
3900      }
3901  
3902      $have_gettext = function_exists( '__' );
3903  
3904      // The $title and these specific $args must always have a non-empty value.
3905      if ( empty( $args['code'] ) ) {
3906          $args['code'] = 'wp_die';
3907      }
3908      if ( empty( $args['response'] ) ) {
3909          $args['response'] = 500;
3910      }
3911      if ( empty( $title ) ) {
3912          $title = $have_gettext ? __( 'WordPress &rsaquo; Error' ) : 'WordPress &rsaquo; Error';
3913      }
3914      if ( empty( $args['text_direction'] ) || ! in_array( $args['text_direction'], array( 'ltr', 'rtl' ), true ) ) {
3915          $args['text_direction'] = 'ltr';
3916          if ( function_exists( 'is_rtl' ) && is_rtl() ) {
3917              $args['text_direction'] = 'rtl';
3918          }
3919      }
3920  
3921      if ( ! empty( $args['charset'] ) ) {
3922          $args['charset'] = _canonical_charset( $args['charset'] );
3923      }
3924  
3925      return array( $message, $title, $args );
3926  }
3927  
3928  /**
3929   * Encode a variable into JSON, with some sanity checks.
3930   *
3931   * @since 4.1.0
3932   * @since 5.3.0 No longer handles support for PHP < 5.6.
3933   *
3934   * @param mixed $data    Variable (usually an array or object) to encode as JSON.
3935   * @param int   $options Optional. Options to be passed to json_encode(). Default 0.
3936   * @param int   $depth   Optional. Maximum depth to walk through $data. Must be
3937   *                       greater than 0. Default 512.
3938   * @return string|false The JSON encoded string, or false if it cannot be encoded.
3939   */
3940  function wp_json_encode( $data, $options = 0, $depth = 512 ) {
3941      $json = json_encode( $data, $options, $depth );
3942  
3943      // If json_encode() was successful, no need to do more sanity checking.
3944      if ( false !== $json ) {
3945          return $json;
3946      }
3947  
3948      try {
3949          $data = _wp_json_sanity_check( $data, $depth );
3950      } catch ( Exception $e ) {
3951          return false;
3952      }
3953  
3954      return json_encode( $data, $options, $depth );
3955  }
3956  
3957  /**
3958   * Perform sanity checks on data that shall be encoded to JSON.
3959   *
3960   * @ignore
3961   * @since 4.1.0
3962   * @access private
3963   *
3964   * @see wp_json_encode()
3965   *
3966   * @throws Exception If depth limit is reached.
3967   *
3968   * @param mixed $data  Variable (usually an array or object) to encode as JSON.
3969   * @param int   $depth Maximum depth to walk through $data. Must be greater than 0.
3970   * @return mixed The sanitized data that shall be encoded to JSON.
3971   */
3972  function _wp_json_sanity_check( $data, $depth ) {
3973      if ( $depth < 0 ) {
3974          throw new Exception( 'Reached depth limit' );
3975      }
3976  
3977      if ( is_array( $data ) ) {
3978          $output = array();
3979          foreach ( $data as $id => $el ) {
3980              // Don't forget to sanitize the ID!
3981              if ( is_string( $id ) ) {
3982                  $clean_id = _wp_json_convert_string( $id );
3983              } else {
3984                  $clean_id = $id;
3985              }
3986  
3987              // Check the element type, so that we're only recursing if we really have to.
3988              if ( is_array( $el ) || is_object( $el ) ) {
3989                  $output[ $clean_id ] = _wp_json_sanity_check( $el, $depth - 1 );
3990              } elseif ( is_string( $el ) ) {
3991                  $output[ $clean_id ] = _wp_json_convert_string( $el );
3992              } else {
3993                  $output[ $clean_id ] = $el;
3994              }
3995          }
3996      } elseif ( is_object( $data ) ) {
3997          $output = new stdClass;
3998          foreach ( $data as $id => $el ) {
3999              if ( is_string( $id ) ) {
4000                  $clean_id = _wp_json_convert_string( $id );
4001              } else {
4002                  $clean_id = $id;
4003              }
4004  
4005              if ( is_array( $el ) || is_object( $el ) ) {
4006                  $output->$clean_id = _wp_json_sanity_check( $el, $depth - 1 );
4007              } elseif ( is_string( $el ) ) {
4008                  $output->$clean_id = _wp_json_convert_string( $el );
4009              } else {
4010                  $output->$clean_id = $el;
4011              }
4012          }
4013      } elseif ( is_string( $data ) ) {
4014          return _wp_json_convert_string( $data );
4015      } else {
4016          return $data;
4017      }
4018  
4019      return $output;
4020  }
4021  
4022  /**
4023   * Convert a string to UTF-8, so that it can be safely encoded to JSON.
4024   *
4025   * @ignore
4026   * @since 4.1.0
4027   * @access private
4028   *
4029   * @see _wp_json_sanity_check()
4030   *
4031   * @param string $string The string which is to be converted.
4032   * @return string The checked string.
4033   */
4034  function _wp_json_convert_string( $string ) {
4035      static $use_mb = null;
4036      if ( is_null( $use_mb ) ) {
4037          $use_mb = function_exists( 'mb_convert_encoding' );
4038      }
4039  
4040      if ( $use_mb ) {
4041          $encoding = mb_detect_encoding( $string, mb_detect_order(), true );
4042          if ( $encoding ) {
4043              return mb_convert_encoding( $string, 'UTF-8', $encoding );
4044          } else {
4045              return mb_convert_encoding( $string, 'UTF-8', 'UTF-8' );
4046          }
4047      } else {
4048          return wp_check_invalid_utf8( $string, true );
4049      }
4050  }
4051  
4052  /**
4053   * Prepares response data to be serialized to JSON.
4054   *
4055   * This supports the JsonSerializable interface for PHP 5.2-5.3 as well.
4056   *
4057   * @ignore
4058   * @since 4.4.0
4059   * @deprecated 5.3.0 This function is no longer needed as support for PHP 5.2-5.3
4060   *                   has been dropped.
4061   * @access private
4062   *
4063   * @param mixed $data Native representation.
4064   * @return bool|int|float|null|string|array Data ready for `json_encode()`.
4065   */
4066  function _wp_json_prepare_data( $data ) {
4067      _deprecated_function( __FUNCTION__, '5.3.0' );
4068      return $data;
4069  }
4070  
4071  /**
4072   * Send a JSON response back to an Ajax request.
4073   *
4074   * @since 3.5.0
4075   * @since 4.7.0 The `$status_code` parameter was added.
4076   *
4077   * @param mixed $response    Variable (usually an array or object) to encode as JSON,
4078   *                           then print and die.
4079   * @param int   $status_code The HTTP status code to output.
4080   */
4081  function wp_send_json( $response, $status_code = null ) {
4082      if ( defined( 'REST_REQUEST' ) && REST_REQUEST ) {
4083          _doing_it_wrong(
4084              __FUNCTION__,
4085              sprintf(
4086                  /* translators: 1: WP_REST_Response, 2: WP_Error */
4087                  __( 'Return a %1$s or %2$s object from your callback when using the REST API.' ),
4088                  'WP_REST_Response',
4089                  'WP_Error'
4090              ),
4091              '5.5.0'
4092          );
4093      }
4094  
4095      if ( ! headers_sent() ) {
4096          header( 'Content-Type: application/json; charset=' . get_option( 'blog_charset' ) );
4097          if ( null !== $status_code ) {
4098              status_header( $status_code );
4099          }
4100      }
4101  
4102      echo wp_json_encode( $response );
4103  
4104      if ( wp_doing_ajax() ) {
4105          wp_die(
4106              '',
4107              '',
4108              array(
4109                  'response' => null,
4110              )
4111          );
4112      } else {
4113          die;
4114      }
4115  }
4116  
4117  /**
4118   * Send a JSON response back to an Ajax request, indicating success.
4119   *
4120   * @since 3.5.0
4121   * @since 4.7.0 The `$status_code` parameter was added.
4122   *
4123   * @param mixed $data        Data to encode as JSON, then print and die.
4124   * @param int   $status_code The HTTP status code to output.
4125   */
4126  function wp_send_json_success( $data = null, $status_code = null ) {
4127      $response = array( 'success' => true );
4128  
4129      if ( isset( $data ) ) {
4130          $response['data'] = $data;
4131      }
4132  
4133      wp_send_json( $response, $status_code );
4134  }
4135  
4136  /**
4137   * Send a JSON response back to an Ajax request, indicating failure.
4138   *
4139   * If the `$data` parameter is a WP_Error object, the errors
4140   * within the object are processed and output as an array of error
4141   * codes and corresponding messages. All other types are output
4142   * without further processing.
4143   *
4144   * @since 3.5.0
4145   * @since 4.1.0 The `$data` parameter is now processed if a WP_Error object is passed in.
4146   * @since 4.7.0 The `$status_code` parameter was added.
4147   *
4148   * @param mixed $data        Data to encode as JSON, then print and die.
4149   * @param int   $status_code The HTTP status code to output.
4150   */
4151  function wp_send_json_error( $data = null, $status_code = null ) {
4152      $response = array( 'success' => false );
4153  
4154      if ( isset( $data ) ) {
4155          if ( is_wp_error( $data ) ) {
4156              $result = array();
4157              foreach ( $data->errors as $code => $messages ) {
4158                  foreach ( $messages as $message ) {
4159                      $result[] = array(
4160                          'code'    => $code,
4161                          'message' => $message,
4162                      );
4163                  }
4164              }
4165  
4166              $response['data'] = $result;
4167          } else {
4168              $response['data'] = $data;
4169          }
4170      }
4171  
4172      wp_send_json( $response, $status_code );
4173  }
4174  
4175  /**
4176   * Checks that a JSONP callback is a valid JavaScript callback name.
4177   *
4178   * Only allows alphanumeric characters and the dot character in callback
4179   * function names. This helps to mitigate XSS attacks caused by directly
4180   * outputting user input.
4181   *
4182   * @since 4.6.0
4183   *
4184   * @param string $callback Supplied JSONP callback function name.
4185   * @return bool Whether the callback function name is valid.
4186   */
4187  function wp_check_jsonp_callback( $callback ) {
4188      if ( ! is_string( $callback ) ) {
4189          return false;
4190      }
4191  
4192      preg_replace( '/[^\w\.]/', '', $callback, -1, $illegal_char_count );
4193  
4194      return 0 === $illegal_char_count;
4195  }
4196  
4197  /**
4198   * Retrieve the WordPress home page URL.
4199   *
4200   * If the constant named 'WP_HOME' exists, then it will be used and returned
4201   * by the function. This can be used to counter the redirection on your local
4202   * development environment.
4203   *
4204   * @since 2.2.0
4205   * @access private
4206   *
4207   * @see WP_HOME
4208   *
4209   * @param string $url URL for the home location.
4210   * @return string Homepage location.
4211   */
4212  function _config_wp_home( $url = '' ) {
4213      if ( defined( 'WP_HOME' ) ) {
4214          return untrailingslashit( WP_HOME );
4215      }
4216      return $url;
4217  }
4218  
4219  /**
4220   * Retrieve the WordPress site URL.
4221   *
4222   * If the constant named 'WP_SITEURL' is defined, then the value in that
4223   * constant will always be returned. This can be used for debugging a site
4224   * on your localhost while not having to change the database to your URL.
4225   *
4226   * @since 2.2.0
4227   * @access private
4228   *
4229   * @see WP_SITEURL
4230   *
4231   * @param string $url URL to set the WordPress site location.
4232   * @return string The WordPress Site URL.
4233   */
4234  function _config_wp_siteurl( $url = '' ) {
4235      if ( defined( 'WP_SITEURL' ) ) {
4236          return untrailingslashit( WP_SITEURL );
4237      }
4238      return $url;
4239  }
4240  
4241  /**
4242   * Delete the fresh site option.
4243   *
4244   * @since 4.7.0
4245   * @access private
4246   */
4247  function _delete_option_fresh_site() {
4248      update_option( 'fresh_site', '0' );
4249  }
4250  
4251  /**
4252   * Set the localized direction for MCE plugin.
4253   *
4254   * Will only set the direction to 'rtl', if the WordPress locale has
4255   * the text direction set to 'rtl'.
4256   *
4257   * Fills in the 'directionality' setting, enables the 'directionality'
4258   * plugin, and adds the 'ltr' button to 'toolbar1', formerly
4259   * 'theme_advanced_buttons1' array keys. These keys are then returned
4260   * in the $mce_init (TinyMCE settings) array.
4261   *
4262   * @since 2.1.0
4263   * @access private
4264   *
4265   * @param array $mce_init MCE settings array.
4266   * @return array Direction set for 'rtl', if needed by locale.
4267   */
4268  function _mce_set_direction( $mce_init ) {
4269      if ( is_rtl() ) {
4270          $mce_init['directionality'] = 'rtl';
4271          $mce_init['rtl_ui']         = true;
4272  
4273          if ( ! empty( $mce_init['plugins'] ) && strpos( $mce_init['plugins'], 'directionality' ) === false ) {
4274              $mce_init['plugins'] .= ',directionality';
4275          }
4276  
4277          if ( ! empty( $mce_init['toolbar1'] ) && ! preg_match( '/\bltr\b/', $mce_init['toolbar1'] ) ) {
4278              $mce_init['toolbar1'] .= ',ltr';
4279          }
4280      }
4281  
4282      return $mce_init;
4283  }
4284  
4285  
4286  /**
4287   * Convert smiley code to the icon graphic file equivalent.
4288   *
4289   * You can turn off smilies, by going to the write setting screen and unchecking
4290   * the box, or by setting 'use_smilies' option to false or removing the option.
4291   *
4292   * Plugins may override the default smiley list by setting the $wpsmiliestrans
4293   * to an array, with the key the code the blogger types in and the value the
4294   * image file.
4295   *
4296   * The $wp_smiliessearch global is for the regular expression and is set each
4297   * time the function is called.
4298   *
4299   * The full list of smilies can be found in the function and won't be listed in
4300   * the description. Probably should create a Codex page for it, so that it is
4301   * available.
4302   *
4303   * @global array $wpsmiliestrans
4304   * @global array $wp_smiliessearch
4305   *
4306   * @since 2.2.0
4307   */
4308  function smilies_init() {
4309      global $wpsmiliestrans, $wp_smiliessearch;
4310  
4311      // Don't bother setting up smilies if they are disabled.
4312      if ( ! get_option( 'use_smilies' ) ) {
4313          return;
4314      }
4315  
4316      if ( ! isset( $wpsmiliestrans ) ) {
4317          $wpsmiliestrans = array(
4318              ':mrgreen:' => 'mrgreen.png',
4319              ':neutral:' => "\xf0\x9f\x98\x90",
4320              ':twisted:' => "\xf0\x9f\x98\x88",
4321              ':arrow:'   => "\xe2\x9e\xa1",
4322              ':shock:'   => "\xf0\x9f\x98\xaf",
4323              ':smile:'   => "\xf0\x9f\x99\x82",
4324              ':???:'     => "\xf0\x9f\x98\x95",
4325              ':cool:'    => "\xf0\x9f\x98\x8e",
4326              ':evil:'    => "\xf0\x9f\x91\xbf",
4327              ':grin:'    => "\xf0\x9f\x98\x80",
4328              ':idea:'    => "\xf0\x9f\x92\xa1",
4329              ':oops:'    => "\xf0\x9f\x98\xb3",
4330              ':razz:'    => "\xf0\x9f\x98\x9b",
4331              ':roll:'    => "\xf0\x9f\x99\x84",
4332              ':wink:'    => "\xf0\x9f\x98\x89",
4333              ':cry:'     => "\xf0\x9f\x98\xa5",
4334              ':eek:'     => "\xf0\x9f\x98\xae",
4335              ':lol:'     => "\xf0\x9f\x98\x86",
4336              ':mad:'     => "\xf0\x9f\x98\xa1",
4337              ':sad:'     => "\xf0\x9f\x99\x81",
4338              '8-)'       => "\xf0\x9f\x98\x8e",
4339              '8-O'       => "\xf0\x9f\x98\xaf",
4340              ':-('       => "\xf0\x9f\x99\x81",
4341              ':-)'       => "\xf0\x9f\x99\x82",
4342              ':-?'       => "\xf0\x9f\x98\x95",
4343              ':-D'       => "\xf0\x9f\x98\x80",
4344              ':-P'       => "\xf0\x9f\x98\x9b",
4345              ':-o'       => "\xf0\x9f\x98\xae",
4346              ':-x'       => "\xf0\x9f\x98\xa1",
4347              ':-|'       => "\xf0\x9f\x98\x90",
4348              ';-)'       => "\xf0\x9f\x98\x89",
4349              // This one transformation breaks regular text with frequency.
4350              //     '8)' => "\xf0\x9f\x98\x8e",
4351              '8O'        => "\xf0\x9f\x98\xaf",
4352              ':('        => "\xf0\x9f\x99\x81",
4353              ':)'        => "\xf0\x9f\x99\x82",
4354              ':?'        => "\xf0\x9f\x98\x95",
4355              ':D'        => "\xf0\x9f\x98\x80",
4356              ':P'        => "\xf0\x9f\x98\x9b",
4357              ':o'        => "\xf0\x9f\x98\xae",
4358              ':x'        => "\xf0\x9f\x98\xa1",
4359              ':|'        => "\xf0\x9f\x98\x90",
4360              ';)'        => "\xf0\x9f\x98\x89",
4361              ':!:'       => "\xe2\x9d\x97",
4362              ':?:'       => "\xe2\x9d\x93",
4363          );
4364      }
4365  
4366      /**
4367       * Filters all the smilies.
4368       *
4369       * This filter must be added before `smilies_init` is run, as
4370       * it is normally only run once to setup the smilies regex.
4371       *
4372       * @since 4.7.0
4373       *
4374       * @param string[] $wpsmiliestrans List of the smilies' hexadecimal representations, keyed by their smily code.
4375       */
4376      $wpsmiliestrans = apply_filters( 'smilies', $wpsmiliestrans );
4377  
4378      if ( count( $wpsmiliestrans ) == 0 ) {
4379          return;
4380      }
4381  
4382      /*
4383       * NOTE: we sort the smilies in reverse key order. This is to make sure
4384       * we match the longest possible smilie (:???: vs :?) as the regular
4385       * expression used below is first-match
4386       */
4387      krsort( $wpsmiliestrans );
4388  
4389      $spaces = wp_spaces_regexp();
4390  
4391      // Begin first "subpattern".
4392      $wp_smiliessearch = '/(?<=' . $spaces . '|^)';
4393  
4394      $subchar = '';
4395      foreach ( (array) $wpsmiliestrans as $smiley => $img ) {
4396          $firstchar = substr( $smiley, 0, 1 );
4397          $rest      = substr( $smiley, 1 );
4398  
4399          // New subpattern?
4400          if ( $firstchar != $subchar ) {
4401              if ( '' !== $subchar ) {
4402                  $wp_smiliessearch .= ')(?=' . $spaces . '|$)';  // End previous "subpattern".
4403                  $wp_smiliessearch .= '|(?<=' . $spaces . '|^)'; // Begin another "subpattern".
4404              }
4405              $subchar           = $firstchar;
4406              $wp_smiliessearch .= preg_quote( $firstchar, '/' ) . '(?:';
4407          } else {
4408              $wp_smiliessearch .= '|';
4409          }
4410          $wp_smiliessearch .= preg_quote( $rest, '/' );
4411      }
4412  
4413      $wp_smiliessearch .= ')(?=' . $spaces . '|$)/m';
4414  
4415  }
4416  
4417  /**
4418   * Merge user defined arguments into defaults array.
4419   *
4420   * This function is used throughout WordPress to allow for both string or array
4421   * to be merged into another array.
4422   *
4423   * @since 2.2.0
4424   * @since 2.3.0 `$args` can now also be an object.
4425   *
4426   * @param string|array|object $args     Value to merge with $defaults.
4427   * @param array               $defaults Optional. Array that serves as the defaults.
4428   *                                      Default empty array.
4429   * @return array Merged user defined values with defaults.
4430   */
4431  function wp_parse_args( $args, $defaults = array() ) {
4432      if ( is_object( $args ) ) {
4433          $parsed_args = get_object_vars( $args );
4434      } elseif ( is_array( $args ) ) {
4435          $parsed_args =& $args;
4436      } else {
4437          wp_parse_str( $args, $parsed_args );
4438      }
4439  
4440      if ( is_array( $defaults ) && $defaults ) {
4441          return array_merge( $defaults, $parsed_args );
4442      }
4443      return $parsed_args;
4444  }
4445  
4446  /**
4447   * Cleans up an array, comma- or space-separated list of scalar values.
4448   *
4449   * @since 5.1.0
4450   *
4451   * @param array|string $list List of values.
4452   * @return array Sanitized array of values.
4453   */
4454  function wp_parse_list( $list ) {
4455      if ( ! is_array( $list ) ) {
4456          return preg_split( '/[\s,]+/', $list, -1, PREG_SPLIT_NO_EMPTY );
4457      }
4458  
4459      return $list;
4460  }
4461  
4462  /**
4463   * Clean up an array, comma- or space-separated list of IDs.
4464   *
4465   * @since 3.0.0
4466   *
4467   * @param array|string $list List of IDs.
4468   * @return int[] Sanitized array of IDs.
4469   */
4470  function wp_parse_id_list( $list ) {
4471      $list = wp_parse_list( $list );
4472  
4473      return array_unique( array_map( 'absint', $list ) );
4474  }
4475  
4476  /**
4477   * Clean up an array, comma- or space-separated list of slugs.
4478   *
4479   * @since 4.7.0
4480   *
4481   * @param array|string $list List of slugs.
4482   * @return string[] Sanitized array of slugs.
4483   */
4484  function wp_parse_slug_list( $list ) {
4485      $list = wp_parse_list( $list );
4486  
4487      return array_unique( array_map( 'sanitize_title', $list ) );
4488  }
4489  
4490  /**
4491   * Extract a slice of an array, given a list of keys.
4492   *
4493   * @since 3.1.0
4494   *
4495   * @param array $array The original array.
4496   * @param array $keys  The list of keys.
4497   * @return array The array slice.
4498   */
4499  function wp_array_slice_assoc( $array, $keys ) {
4500      $slice = array();
4501      foreach ( $keys as $key ) {
4502          if ( isset( $array[ $key ] ) ) {
4503              $slice[ $key ] = $array[ $key ];
4504          }
4505      }
4506  
4507      return $slice;
4508  }
4509  
4510  /**
4511   * Determines if the variable is a numeric-indexed array.
4512   *
4513   * @since 4.4.0
4514   *
4515   * @param mixed $data Variable to check.
4516   * @return bool Whether the variable is a list.
4517   */
4518  function wp_is_numeric_array( $data ) {
4519      if ( ! is_array( $data ) ) {
4520          return false;
4521      }
4522  
4523      $keys        = array_keys( $data );
4524      $string_keys = array_filter( $keys, 'is_string' );
4525      return count( $string_keys ) === 0;
4526  }
4527  
4528  /**
4529   * Filters a list of objects, based on a set of key => value arguments.
4530   *
4531   * @since 3.0.0
4532   * @since 4.7.0 Uses `WP_List_Util` class.
4533   *
4534   * @param array       $list     An array of objects to filter
4535   * @param array       $args     Optional. An array of key => value arguments to match
4536   *                              against each object. Default empty array.
4537   * @param string      $operator Optional. The logical operation to perform. 'or' means
4538   *                              only one element from the array needs to match; 'and'
4539   *                              means all elements must match; 'not' means no elements may
4540   *                              match. Default 'and'.
4541   * @param bool|string $field    A field from the object to place instead of the entire object.
4542   *                              Default false.
4543   * @return array A list of objects or object fields.
4544   */
4545  function wp_filter_object_list( $list, $args = array(), $operator = 'and', $field = false ) {
4546      if ( ! is_array( $list ) ) {
4547          return array();
4548      }
4549  
4550      $util = new WP_List_Util( $list );
4551  
4552      $util->filter( $args, $operator );
4553  
4554      if ( $field ) {
4555          $util->pluck( $field );
4556      }
4557  
4558      return $util->get_output();
4559  }
4560  
4561  /**
4562   * Filters a list of objects, based on a set of key => value arguments.
4563   *
4564   * @since 3.1.0
4565   * @since 4.7.0 Uses `WP_List_Util` class.
4566   *
4567   * @param array  $list     An array of objects to filter.
4568   * @param array  $args     Optional. An array of key => value arguments to match
4569   *                         against each object. Default empty array.
4570   * @param string $operator Optional. The logical operation to perform. 'AND' means
4571   *                         all elements from the array must match. 'OR' means only
4572   *                         one element needs to match. 'NOT' means no elements may
4573   *                         match. Default 'AND'.
4574   * @return array Array of found values.
4575   */
4576  function wp_list_filter( $list, $args = array(), $operator = 'AND' ) {
4577      if ( ! is_array( $list ) ) {
4578          return array();
4579      }
4580  
4581      $util = new WP_List_Util( $list );
4582      return $util->filter( $args, $operator );
4583  }
4584  
4585  /**
4586   * Pluck a certain field out of each object in a list.
4587   *
4588   * This has the same functionality and prototype of
4589   * array_column() (PHP 5.5) but also supports objects.
4590   *
4591   * @since 3.1.0
4592   * @since 4.0.0 $index_key parameter added.
4593   * @since 4.7.0 Uses `WP_List_Util` class.
4594   *
4595   * @param array      $list      List of objects or arrays
4596   * @param int|string $field     Field from the object to place instead of the entire object
4597   * @param int|string $index_key Optional. Field from the object to use as keys for the new array.
4598   *                              Default null.
4599   * @return array Array of found values. If `$index_key` is set, an array of found values with keys
4600   *               corresponding to `$index_key`. If `$index_key` is null, array keys from the original
4601   *               `$list` will be preserved in the results.
4602   */
4603  function wp_list_pluck( $list, $field, $index_key = null ) {
4604      $util = new WP_List_Util( $list );
4605      return $util->pluck( $field, $index_key );
4606  }
4607  
4608  /**
4609   * Sorts a list of objects, based on one or more orderby arguments.
4610   *
4611   * @since 4.7.0
4612   *
4613   * @param array        $list          An array of objects to sort.
4614   * @param string|array $orderby       Optional. Either the field name to order by or an array
4615   *                                    of multiple orderby fields as $orderby => $order.
4616   * @param string       $order         Optional. Either 'ASC' or 'DESC'. Only used if $orderby
4617   *                                    is a string.
4618   * @param bool         $preserve_keys Optional. Whether to preserve keys. Default false.
4619   * @return array The sorted array.
4620   */
4621  function wp_list_sort( $list, $orderby = array(), $order = 'ASC', $preserve_keys = false ) {
4622      if ( ! is_array( $list ) ) {
4623          return array();
4624      }
4625  
4626      $util = new WP_List_Util( $list );
4627      return $util->sort( $orderby, $order, $preserve_keys );
4628  }
4629  
4630  /**
4631   * Determines if Widgets library should be loaded.
4632   *
4633   * Checks to make sure that the widgets library hasn't already been loaded.
4634   * If it hasn't, then it will load the widgets library and run an action hook.
4635   *
4636   * @since 2.2.0
4637   */
4638  function wp_maybe_load_widgets() {
4639      /**
4640       * Filters whether to load the Widgets library.
4641       *
4642       * Returning a falsey value from the filter will effectively short-circuit
4643       * the Widgets library from loading.
4644       *
4645       * @since 2.8.0
4646       *
4647       * @param bool $wp_maybe_load_widgets Whether to load the Widgets library.
4648       *                                    Default true.
4649       */
4650      if ( ! apply_filters( 'load_default_widgets', true ) ) {
4651          return;
4652      }
4653  
4654      require_once  ABSPATH . WPINC . '/default-widgets.php';
4655  
4656      add_action( '_admin_menu', 'wp_widgets_add_menu' );
4657  }
4658  
4659  /**
4660   * Append the Widgets menu to the themes main menu.
4661   *
4662   * @since 2.2.0
4663   *
4664   * @global array $submenu
4665   */
4666  function wp_widgets_add_menu() {
4667      global $submenu;
4668  
4669      if ( ! current_theme_supports( 'widgets' ) ) {
4670          return;
4671      }
4672  
4673      $submenu['themes.php'][7] = array( __( 'Widgets' ), 'edit_theme_options', 'widgets.php' );
4674      ksort( $submenu['themes.php'], SORT_NUMERIC );
4675  }
4676  
4677  /**
4678   * Flush all output buffers for PHP 5.2.
4679   *
4680   * Make sure all output buffers are flushed before our singletons are destroyed.
4681   *
4682   * @since 2.2.0
4683   */
4684  function wp_ob_end_flush_all() {
4685      $levels = ob_get_level();
4686      for ( $i = 0; $i < $levels; $i++ ) {
4687          ob_end_flush();
4688      }
4689  }
4690  
4691  /**
4692   * Load custom DB error or display WordPress DB error.
4693   *
4694   * If a file exists in the wp-content directory named db-error.php, then it will
4695   * be loaded instead of displaying the WordPress DB error. If it is not found,
4696   * then the WordPress DB error will be displayed instead.
4697   *
4698   * The WordPress DB error sets the HTTP status header to 500 to try to prevent
4699   * search engines from caching the message. Custom DB messages should do the
4700   * same.
4701   *
4702   * This function was backported to WordPress 2.3.2, but originally was added
4703   * in WordPress 2.5.0.
4704   *
4705   * @since 2.3.2
4706   *
4707   * @global wpdb $wpdb WordPress database abstraction object.
4708   */
4709  function dead_db() {
4710      global $wpdb;
4711  
4712      wp_load_translations_early();
4713  
4714      // Load custom DB error template, if present.
4715      if ( file_exists( WP_CONTENT_DIR . '/db-error.php' ) ) {
4716          require_once WP_CONTENT_DIR . '/db-error.php';
4717          die();
4718      }
4719  
4720      // If installing or in the admin, provide the verbose message.
4721      if ( wp_installing() || defined( 'WP_ADMIN' ) ) {
4722          wp_die( $wpdb->error );
4723      }
4724  
4725      // Otherwise, be terse.
4726      wp_die( '<h1>' . __( 'Error establishing a database connection' ) . '</h1>', __( 'Database Error' ) );
4727  }
4728  
4729  /**
4730   * Convert a value to non-negative integer.
4731   *
4732   * @since 2.5.0
4733   *
4734   * @param mixed $maybeint Data you wish to have converted to a non-negative integer.
4735   * @return int A non-negative integer.
4736   */
4737  function absint( $maybeint ) {
4738      return abs( intval( $maybeint ) );
4739  }
4740  
4741  /**
4742   * Mark a function as deprecated and inform when it has been used.
4743   *
4744   * There is a {@see 'hook deprecated_function_run'} that will be called that can be used
4745   * to get the backtrace up to what file and function called the deprecated
4746   * function.
4747   *
4748   * The current behavior is to trigger a user error if `WP_DEBUG` is true.
4749   *
4750   * This function is to be used in every function that is deprecated.
4751   *
4752   * @since 2.5.0
4753   * @since 5.4.0 This function is no longer marked as "private".
4754   * @since 5.4.0 The error type is now classified as E_USER_DEPRECATED (used to default to E_USER_NOTICE).
4755   *
4756   * @param string $function    The function that was called.
4757   * @param string $version     The version of WordPress that deprecated the function.
4758   * @param string $replacement Optional. The function that should have been called. Default empty.
4759   */
4760  function _deprecated_function( $function, $version, $replacement = '' ) {
4761  
4762      /**
4763       * Fires when a deprecated function is called.
4764       *
4765       * @since 2.5.0
4766       *
4767       * @param string $function    The function that was called.
4768       * @param string $replacement The function that should have been called.
4769       * @param string $version     The version of WordPress that deprecated the function.
4770       */
4771      do_action( 'deprecated_function_run', $function, $replacement, $version );
4772  
4773      /**
4774       * Filters whether to trigger an error for deprecated functions.
4775       *
4776       * @since 2.5.0
4777       *
4778       * @param bool $trigger Whether to trigger the error for deprecated functions. Default true.
4779       */
4780      if ( WP_DEBUG && apply_filters( 'deprecated_function_trigger_error', true ) ) {
4781          if ( function_exists( '__' ) ) {
4782              if ( $replacement ) {
4783                  trigger_error(
4784                      sprintf(
4785                          /* translators: 1: PHP function name, 2: Version number, 3: Alternative function name. */
4786                          __( '%1$s is <strong>deprecated</strong> since version %2$s! Use %3$s instead.' ),
4787                          $function,
4788                          $version,
4789                          $replacement
4790                      ),
4791                      E_USER_DEPRECATED
4792                  );
4793              } else {
4794                  trigger_error(
4795                      sprintf(
4796                          /* translators: 1: PHP function name, 2: Version number. */
4797                          __( '%1$s is <strong>deprecated</strong> since version %2$s with no alternative available.' ),
4798                          $function,
4799                          $version
4800                      ),
4801                      E_USER_DEPRECATED
4802                  );
4803              }
4804          } else {
4805              if ( $replacement ) {
4806                  trigger_error(
4807                      sprintf(
4808                          '%1$s is <strong>deprecated</strong> since version %2$s! Use %3$s instead.',
4809                          $function,
4810                          $version,
4811                          $replacement
4812                      ),
4813                      E_USER_DEPRECATED
4814                  );
4815              } else {
4816                  trigger_error(
4817                      sprintf(
4818                          '%1$s is <strong>deprecated</strong> since version %2$s with no alternative available.',
4819                          $function,
4820                          $version
4821                      ),
4822                      E_USER_DEPRECATED
4823                  );
4824              }
4825          }
4826      }
4827  }
4828  
4829  /**
4830   * Marks a constructor as deprecated and informs when it has been used.
4831   *
4832   * Similar to _deprecated_function(), but with different strings. Used to
4833   * remove PHP4 style constructors.
4834   *
4835   * The current behavior is to trigger a user error if `WP_DEBUG` is true.
4836   *
4837   * This function is to be used in every PHP4 style constructor method that is deprecated.
4838   *
4839   * @since 4.3.0
4840   * @since 4.5.0 Added the `$parent_class` parameter.
4841   * @since 5.4.0 This function is no longer marked as "private".
4842   * @since 5.4.0 The error type is now classified as E_USER_DEPRECATED (used to default to E_USER_NOTICE).
4843   *
4844   * @param string $class        The class containing the deprecated constructor.
4845   * @param string $version      The version of WordPress that deprecated the function.
4846   * @param string $parent_class Optional. The parent class calling the deprecated constructor.
4847   *                             Default empty string.
4848   */
4849  function _deprecated_constructor( $class, $version, $parent_class = '' ) {
4850  
4851      /**
4852       * Fires when a deprecated constructor is called.
4853       *
4854       * @since 4.3.0
4855       * @since 4.5.0 Added the `$parent_class` parameter.
4856       *
4857       * @param string $class        The class containing the deprecated constructor.
4858       * @param string $version      The version of WordPress that deprecated the function.
4859       * @param string $parent_class The parent class calling the deprecated constructor.
4860       */
4861      do_action( 'deprecated_constructor_run', $class, $version, $parent_class );
4862  
4863      /**
4864       * Filters whether to trigger an error for deprecated functions.
4865       *
4866       * `WP_DEBUG` must be true in addition to the filter evaluating to true.
4867       *
4868       * @since 4.3.0
4869       *
4870       * @param bool $trigger Whether to trigger the error for deprecated functions. Default true.
4871       */
4872      if ( WP_DEBUG && apply_filters( 'deprecated_constructor_trigger_error', true ) ) {
4873          if ( function_exists( '__' ) ) {
4874              if ( $parent_class ) {
4875                  trigger_error(
4876                      sprintf(
4877                          /* translators: 1: PHP class name, 2: PHP parent class name, 3: Version number, 4: __construct() method. */
4878                          __( 'The called constructor method for %1$s in %2$s is <strong>deprecated</strong> since version %3$s! Use %4$s instead.' ),
4879                          $class,
4880                          $parent_class,
4881                          $version,
4882                          '<code>__construct()</code>'
4883                      ),
4884                      E_USER_DEPRECATED
4885                  );
4886              } else {
4887                  trigger_error(
4888                      sprintf(
4889                          /* translators: 1: PHP class name, 2: Version number, 3: __construct() method. */
4890                          __( 'The called constructor method for %1$s is <strong>deprecated</strong> since version %2$s! Use %3$s instead.' ),
4891                          $class,
4892                          $version,
4893                          '<code>__construct()</code>'
4894                      ),
4895                      E_USER_DEPRECATED
4896                  );
4897              }
4898          } else {
4899              if ( $parent_class ) {
4900                  trigger_error(
4901                      sprintf(
4902                          'The called constructor method for %1$s in %2$s is <strong>deprecated</strong> since version %3$s! Use %4$s instead.',
4903                          $class,
4904                          $parent_class,
4905                          $version,
4906                          '<code>__construct()</code>'
4907                      ),
4908                      E_USER_DEPRECATED
4909                  );
4910              } else {
4911                  trigger_error(
4912                      sprintf(
4913                          'The called constructor method for %1$s is <strong>deprecated</strong> since version %2$s! Use %3$s instead.',
4914                          $class,
4915                          $version,
4916                          '<code>__construct()</code>'
4917                      ),
4918                      E_USER_DEPRECATED
4919                  );
4920              }
4921          }
4922      }
4923  
4924  }
4925  
4926  /**
4927   * Mark a file as deprecated and inform when it has been used.
4928   *
4929   * There is a hook {@see 'deprecated_file_included'} that will be called that can be used
4930   * to get the backtrace up to what file and function included the deprecated
4931   * file.
4932   *
4933   * The current behavior is to trigger a user error if `WP_DEBUG` is true.
4934   *
4935   * This function is to be used in every file that is deprecated.
4936   *
4937   * @since 2.5.0
4938   * @since 5.4.0 This function is no longer marked as "private".
4939   * @since 5.4.0 The error type is now classified as E_USER_DEPRECATED (used to default to E_USER_NOTICE).
4940   *
4941   * @param string $file        The file that was included.
4942   * @param string $version     The version of WordPress that deprecated the file.
4943   * @param string $replacement Optional. The file that should have been included based on ABSPATH.
4944   *                            Default empty.
4945   * @param string $message     Optional. A message regarding the change. Default empty.
4946   */
4947  function _deprecated_file( $file, $version, $replacement = '', $message = '' ) {
4948  
4949      /**
4950       * Fires when a deprecated file is called.
4951       *
4952       * @since 2.5.0
4953       *
4954       * @param string $file        The file that was called.
4955       * @param string $replacement The file that should have been included based on ABSPATH.
4956       * @param string $version     The version of WordPress that deprecated the file.
4957       * @param string $message     A message regarding the change.
4958       */
4959      do_action( 'deprecated_file_included', $file, $replacement, $version, $message );
4960  
4961      /**
4962       * Filters whether to trigger an error for deprecated files.
4963       *
4964       * @since 2.5.0
4965       *
4966       * @param bool $trigger Whether to trigger the error for deprecated files. Default true.
4967       */
4968      if ( WP_DEBUG && apply_filters( 'deprecated_file_trigger_error', true ) ) {
4969          $message = empty( $message ) ? '' : ' ' . $message;
4970  
4971          if ( function_exists( '__' ) ) {
4972              if ( $replacement ) {
4973                  trigger_error(
4974                      sprintf(
4975                          /* translators: 1: PHP file name, 2: Version number, 3: Alternative file name. */
4976                          __( '%1$s is <strong>deprecated</strong> since version %2$s! Use %3$s instead.' ),
4977                          $file,
4978                          $version,
4979                          $replacement
4980                      ) . $message,
4981                      E_USER_DEPRECATED
4982                  );
4983              } else {
4984                  trigger_error(
4985                      sprintf(
4986                          /* translators: 1: PHP file name, 2: Version number. */
4987                          __( '%1$s is <strong>deprecated</strong> since version %2$s with no alternative available.' ),
4988                          $file,
4989                          $version
4990                      ) . $message,
4991                      E_USER_DEPRECATED
4992                  );
4993              }
4994          } else {
4995              if ( $replacement ) {
4996                  trigger_error(
4997                      sprintf(
4998                          '%1$s is <strong>deprecated</strong> since version %2$s! Use %3$s instead.',
4999                          $file,
5000                          $version,
5001                          $replacement
5002                      ) . $message,
5003                      E_USER_DEPRECATED
5004                  );
5005              } else {
5006                  trigger_error(
5007                      sprintf(
5008                          '%1$s is <strong>deprecated</strong> since version %2$s with no alternative available.',
5009                          $file,
5010                          $version
5011                      ) . $message,
5012                      E_USER_DEPRECATED
5013                  );
5014              }
5015          }
5016      }
5017  }
5018  /**
5019   * Mark a function argument as deprecated and inform when it has been used.
5020   *
5021   * This function is to be used whenever a deprecated function argument is used.
5022   * Before this function is called, the argument must be checked for whether it was
5023   * used by comparing it to its default value or evaluating whether it is empty.
5024   * For example:
5025   *
5026   *     if ( ! empty( $deprecated ) ) {
5027   *         _deprecated_argument( __FUNCTION__, '3.0.0' );
5028   *     }
5029   *
5030   * There is a hook deprecated_argument_run that will be called that can be used
5031   * to get the backtrace up to what file and function used the deprecated
5032   * argument.
5033   *
5034   * The current behavior is to trigger a user error if WP_DEBUG is true.
5035   *
5036   * @since 3.0.0
5037   * @since 5.4.0 This function is no longer marked as "private".
5038   * @since 5.4.0 The error type is now classified as E_USER_DEPRECATED (used to default to E_USER_NOTICE).
5039   *
5040   * @param string $function The function that was called.
5041   * @param string $version  The version of WordPress that deprecated the argument used.
5042   * @param string $message  Optional. A message regarding the change. Default empty.
5043   */
5044  function _deprecated_argument( $function, $version, $message = '' ) {
5045  
5046      /**
5047       * Fires when a deprecated argument is called.
5048       *
5049       * @since 3.0.0
5050       *
5051       * @param string $function The function that was called.
5052       * @param string $message  A message regarding the change.
5053       * @param string $version  The version of WordPress that deprecated the argument used.
5054       */
5055      do_action( 'deprecated_argument_run', $function, $message, $version );
5056  
5057      /**
5058       * Filters whether to trigger an error for deprecated arguments.
5059       *
5060       * @since 3.0.0
5061       *
5062       * @param bool $trigger Whether to trigger the error for deprecated arguments. Default true.
5063       */
5064      if ( WP_DEBUG && apply_filters( 'deprecated_argument_trigger_error', true ) ) {
5065          if ( function_exists( '__' ) ) {
5066              if ( $message ) {
5067                  trigger_error(
5068                      sprintf(
5069                          /* translators: 1: PHP function name, 2: Version number, 3: Optional message regarding the change. */
5070                          __( '%1$s was called with an argument that is <strong>deprecated</strong> since version %2$s! %3$s' ),
5071                          $function,
5072                          $version,
5073                          $message
5074                      ),
5075                      E_USER_DEPRECATED
5076                  );
5077              } else {
5078                  trigger_error(
5079                      sprintf(
5080                          /* translators: 1: PHP function name, 2: Version number. */
5081                          __( '%1$s was called with an argument that is <strong>deprecated</strong> since version %2$s with no alternative available.' ),
5082                          $function,
5083                          $version
5084                      ),
5085                      E_USER_DEPRECATED
5086                  );
5087              }
5088          } else {
5089              if ( $message ) {
5090                  trigger_error(
5091                      sprintf(
5092                          '%1$s was called with an argument that is <strong>deprecated</strong> since version %2$s! %3$s',
5093                          $function,
5094                          $version,
5095                          $message
5096                      ),
5097                      E_USER_DEPRECATED
5098                  );
5099              } else {
5100                  trigger_error(
5101                      sprintf(
5102                          '%1$s was called with an argument that is <strong>deprecated</strong> since version %2$s with no alternative available.',
5103                          $function,
5104                          $version
5105                      ),
5106                      E_USER_DEPRECATED
5107                  );
5108              }
5109          }
5110      }
5111  }
5112  
5113  /**
5114   * Marks a deprecated action or filter hook as deprecated and throws a notice.
5115   *
5116   * Use the {@see 'deprecated_hook_run'} action to get the backtrace describing where
5117   * the deprecated hook was called.
5118   *
5119   * Default behavior is to trigger a user error if `WP_DEBUG` is true.
5120   *
5121   * This function is called by the do_action_deprecated() and apply_filters_deprecated()
5122   * functions, and so generally does not need to be called directly.
5123   *
5124   * @since 4.6.0
5125   * @since 5.4.0 The error type is now classified as E_USER_DEPRECATED (used to default to E_USER_NOTICE).
5126   * @access private
5127   *
5128   * @param string $hook        The hook that was used.
5129   * @param string $version     The version of WordPress that deprecated the hook.
5130   * @param string $replacement Optional. The hook that should have been used. Default empty.
5131   * @param string $message     Optional. A message regarding the change. Default empty.
5132   */
5133  function _deprecated_hook( $hook, $version, $replacement = '', $message = '' ) {
5134      /**
5135       * Fires when a deprecated hook is called.
5136       *
5137       * @since 4.6.0
5138       *
5139       * @param string $hook        The hook that was called.
5140       * @param string $replacement The hook that should be used as a replacement.
5141       * @param string $version     The version of WordPress that deprecated the argument used.
5142       * @param string $message     A message regarding the change.
5143       */
5144      do_action( 'deprecated_hook_run', $hook, $replacement, $version, $message );
5145  
5146      /**
5147       * Filters whether to trigger deprecated hook errors.
5148       *
5149       * @since 4.6.0
5150       *
5151       * @param bool $trigger Whether to trigger deprecated hook errors. Requires
5152       *                      `WP_DEBUG` to be defined true.
5153       */
5154      if ( WP_DEBUG && apply_filters( 'deprecated_hook_trigger_error', true ) ) {
5155          $message = empty( $message ) ? '' : ' ' . $message;
5156  
5157          if ( $replacement ) {
5158              trigger_error(
5159                  sprintf(
5160                      /* translators: 1: WordPress hook name, 2: Version number, 3: Alternative hook name. */
5161                      __( '%1$s is <strong>deprecated</strong> since version %2$s! Use %3$s instead.' ),
5162                      $hook,
5163                      $version,
5164                      $replacement
5165                  ) . $message,
5166                  E_USER_DEPRECATED
5167              );
5168          } else {
5169              trigger_error(
5170                  sprintf(
5171                      /* translators: 1: WordPress hook name, 2: Version number. */
5172                      __( '%1$s is <strong>deprecated</strong> since version %2$s with no alternative available.' ),
5173                      $hook,
5174                      $version
5175                  ) . $message,
5176                  E_USER_DEPRECATED
5177              );
5178          }
5179      }
5180  }
5181  
5182  /**
5183   * Mark something as being incorrectly called.
5184   *
5185   * There is a hook {@see 'doing_it_wrong_run'} that will be called that can be used
5186   * to get the backtrace up to what file and function called the deprecated
5187   * function.
5188   *
5189   * The current behavior is to trigger a user error if `WP_DEBUG` is true.
5190   *
5191   * @since 3.1.0
5192   * @since 5.4.0 This function is no longer marked as "private".
5193   *
5194   * @param string $function The function that was called.
5195   * @param string $message  A message explaining what has been done incorrectly.
5196   * @param string $version  The version of WordPress where the message was added.
5197   */
5198  function _doing_it_wrong( $function, $message, $version ) {
5199  
5200      /**
5201       * Fires when the given function is being used incorrectly.
5202       *
5203       * @since 3.1.0
5204       *
5205       * @param string $function The function that was called.
5206       * @param string $message  A message explaining what has been done incorrectly.
5207       * @param string $version  The version of WordPress where the message was added.
5208       */
5209      do_action( 'doing_it_wrong_run', $function, $message, $version );
5210  
5211      /**
5212       * Filters whether to trigger an error for _doing_it_wrong() calls.
5213       *
5214       * @since 3.1.0
5215       * @since 5.1.0 Added the $function, $message and $version parameters.
5216       *
5217       * @param bool   $trigger  Whether to trigger the error for _doing_it_wrong() calls. Default true.
5218       * @param string $function The function that was called.
5219       * @param string $message  A message explaining what has been done incorrectly.
5220       * @param string $version  The version of WordPress where the message was added.
5221       */
5222      if ( WP_DEBUG && apply_filters( 'doing_it_wrong_trigger_error', true, $function, $message, $version ) ) {
5223          if ( function_exists( '__' ) ) {
5224              if ( $version ) {
5225                  /* translators: %s: Version number. */
5226                  $version = sprintf( __( '(This message was added in version %s.)' ), $version );
5227              }
5228  
5229              $message .= ' ' . sprintf(
5230                  /* translators: %s: Documentation URL. */
5231                  __( 'Please see <a href="%s">Debugging in WordPress</a> for more information.' ),
5232                  __( 'https://wordpress.org/support/article/debugging-in-wordpress/' )
5233              );
5234  
5235              trigger_error(
5236                  sprintf(
5237                      /* translators: Developer debugging message. 1: PHP function name, 2: Explanatory message, 3: WordPress version number. */
5238                      __( '%1$s was called <strong>incorrectly</strong>. %2$s %3$s' ),
5239                      $function,
5240                      $message,
5241                      $version
5242                  ),
5243                  E_USER_NOTICE
5244              );
5245          } else {
5246              if ( $version ) {
5247                  $version = sprintf( '(This message was added in version %s.)', $version );
5248              }
5249  
5250              $message .= sprintf(
5251                  ' Please see <a href="%s">Debugging in WordPress</a> for more information.',
5252                  'https://wordpress.org/support/article/debugging-in-wordpress/'
5253              );
5254  
5255              trigger_error(
5256                  sprintf(
5257                      '%1$s was called <strong>incorrectly</strong>. %2$s %3$s',
5258                      $function,
5259                      $message,
5260                      $version
5261                  ),
5262                  E_USER_NOTICE
5263              );
5264          }
5265      }
5266  }
5267  
5268  /**
5269   * Is the server running earlier than 1.5.0 version of lighttpd?
5270   *
5271   * @since 2.5.0
5272   *
5273   * @return bool Whether the server is running lighttpd < 1.5.0.
5274   */
5275  function is_lighttpd_before_150() {
5276      $server_parts    = explode( '/', isset( $_SERVER['SERVER_SOFTWARE'] ) ? $_SERVER['SERVER_SOFTWARE'] : '' );
5277      $server_parts[1] = isset( $server_parts[1] ) ? $server_parts[1] : '';
5278  
5279      return ( 'lighttpd' === $server_parts[0] && -1 == version_compare( $server_parts[1], '1.5.0' ) );
5280  }
5281  
5282  /**
5283   * Does the specified module exist in the Apache config?
5284   *
5285   * @since 2.5.0
5286   *
5287   * @global bool $is_apache
5288   *
5289   * @param string $mod     The module, e.g. mod_rewrite.
5290   * @param bool   $default Optional. The default return value if the module is not found. Default false.
5291   * @return bool Whether the specified module is loaded.
5292   */
5293  function apache_mod_loaded( $mod, $default = false ) {
5294      global $is_apache;
5295  
5296      if ( ! $is_apache ) {
5297          return false;
5298      }
5299  
5300      if ( function_exists( 'apache_get_modules' ) ) {
5301          $mods = apache_get_modules();
5302          if ( in_array( $mod, $mods, true ) ) {
5303              return true;
5304          }
5305      } elseif ( function_exists( 'phpinfo' ) && false === strpos( ini_get( 'disable_functions' ), 'phpinfo' ) ) {
5306              ob_start();
5307              phpinfo( 8 );
5308              $phpinfo = ob_get_clean();
5309          if ( false !== strpos( $phpinfo, $mod ) ) {
5310              return true;
5311          }
5312      }
5313  
5314      return $default;
5315  }
5316  
5317  /**
5318   * Check if IIS 7+ supports pretty permalinks.
5319   *
5320   * @since 2.8.0
5321   *
5322   * @global bool $is_iis7
5323   *
5324   * @return bool Whether IIS7 supports permalinks.
5325   */
5326  function iis7_supports_permalinks() {
5327      global $is_iis7;
5328  
5329      $supports_permalinks = false;
5330      if ( $is_iis7 ) {
5331          /* First we check if the DOMDocument class exists. If it does not exist, then we cannot
5332           * easily update the xml configuration file, hence we just bail out and tell user that
5333           * pretty permalinks cannot be used.
5334           *
5335           * Next we check if the URL Rewrite Module 1.1 is loaded and enabled for the web site. When
5336           * URL Rewrite 1.1 is loaded it always sets a server variable called 'IIS_UrlRewriteModule'.
5337           * Lastly we make sure that PHP is running via FastCGI. This is important because if it runs
5338           * via ISAPI then pretty permalinks will not work.
5339           */
5340          $supports_permalinks = class_exists( 'DOMDocument', false ) && isset( $_SERVER['IIS_UrlRewriteModule'] ) && ( 'cgi-fcgi' === PHP_SAPI );
5341      }
5342  
5343      /**
5344       * Filters whether IIS 7+ supports pretty permalinks.
5345       *
5346       * @since 2.8.0
5347       *
5348       * @param bool $supports_permalinks Whether IIS7 supports permalinks. Default false.
5349       */
5350      return apply_filters( 'iis7_supports_permalinks', $supports_permalinks );
5351  }
5352  
5353  /**
5354   * Validates a file name and path against an allowed set of rules.
5355   *
5356   * A return value of `1` means the file path contains directory traversal.
5357   *
5358   * A return value of `2` means the file path contains a Windows drive path.
5359   *
5360   * A return value of `3` means the file is not in the allowed files list.
5361   *
5362   * @since 1.2.0
5363   *
5364   * @param string   $file          File path.
5365   * @param string[] $allowed_files Optional. Array of allowed files.
5366   * @return int 0 means nothing is wrong, greater than 0 means something was wrong.
5367   */
5368  function validate_file( $file, $allowed_files = array() ) {
5369      // `../` on its own is not allowed:
5370      if ( '../' === $file ) {
5371          return 1;
5372      }
5373  
5374      // More than one occurence of `../` is not allowed:
5375      if ( preg_match_all( '#\.\./#', $file, $matches, PREG_SET_ORDER ) && ( count( $matches ) > 1 ) ) {
5376          return 1;
5377      }
5378  
5379      // `../` which does not occur at the end of the path is not allowed:
5380      if ( false !== strpos( $file, '../' ) && '../' !== mb_substr( $file, -3, 3 ) ) {
5381          return 1;
5382      }
5383  
5384      // Files not in the allowed file list are not allowed:
5385      if ( ! empty( $allowed_files ) && ! in_array( $file, $allowed_files, true ) ) {
5386          return 3;
5387      }
5388  
5389      // Absolute Windows drive paths are not allowed:
5390      if ( ':' === substr( $file, 1, 1 ) ) {
5391          return 2;
5392      }
5393  
5394      return 0;
5395  }
5396  
5397  /**
5398   * Whether to force SSL used for the Administration Screens.
5399   *
5400   * @since 2.6.0
5401   *
5402   * @param string|bool $force Optional. Whether to force SSL in admin screens. Default null.
5403   * @return bool True if forced, false if not forced.
5404   */
5405  function force_ssl_admin( $force = null ) {
5406      static $forced = false;
5407  
5408      if ( ! is_null( $force ) ) {
5409          $old_forced = $forced;
5410          $forced     = $force;
5411          return $old_forced;
5412      }
5413  
5414      return $forced;
5415  }
5416  
5417  /**
5418   * Guess the URL for the site.
5419   *
5420   * Will remove wp-admin links to retrieve only return URLs not in the wp-admin
5421   * directory.
5422   *
5423   * @since 2.6.0
5424   *
5425   * @return string The guessed URL.
5426   */
5427  function wp_guess_url() {
5428      if ( defined( 'WP_SITEURL' ) && '' !== WP_SITEURL ) {
5429          $url = WP_SITEURL;
5430      } else {
5431          $abspath_fix         = str_replace( '\\', '/', ABSPATH );
5432          $script_filename_dir = dirname( $_SERVER['SCRIPT_FILENAME'] );
5433  
5434          // The request is for the admin.
5435          if ( strpos( $_SERVER['REQUEST_URI'], 'wp-admin' ) !== false || strpos( $_SERVER['REQUEST_URI'], 'wp-login.php' ) !== false ) {
5436              $path = preg_replace( '#/(wp-admin/.*|wp-login.php)#i', '', $_SERVER['REQUEST_URI'] );
5437  
5438              // The request is for a file in ABSPATH.
5439          } elseif ( $script_filename_dir . '/' === $abspath_fix ) {
5440              // Strip off any file/query params in the path.
5441              $path = preg_replace( '#/[^/]*$#i', '', $_SERVER['PHP_SELF'] );
5442  
5443          } else {
5444              if ( false !== strpos( $_SERVER['SCRIPT_FILENAME'], $abspath_fix ) ) {
5445                  // Request is hitting a file inside ABSPATH.
5446                  $directory = str_replace( ABSPATH, '', $script_filename_dir );
5447                  // Strip off the subdirectory, and any file/query params.
5448                  $path = preg_replace( '#/' . preg_quote( $directory, '#' ) . '/[^/]*$#i', '', $_SERVER['REQUEST_URI'] );
5449              } elseif ( false !== strpos( $abspath_fix, $script_filename_dir ) ) {
5450                  // Request is hitting a file above ABSPATH.
5451                  $subdirectory = substr( $abspath_fix, strpos( $abspath_fix, $script_filename_dir ) + strlen( $script_filename_dir ) );
5452                  // Strip off any file/query params from the path, appending the subdirectory to the installation.
5453                  $path = preg_replace( '#/[^/]*$#i', '', $_SERVER['REQUEST_URI'] ) . $subdirectory;
5454              } else {
5455                  $path = $_SERVER['REQUEST_URI'];
5456              }
5457          }
5458  
5459          $schema = is_ssl() ? 'https://' : 'http://'; // set_url_scheme() is not defined yet.
5460          $url    = $schema . $_SERVER['HTTP_HOST'] . $path;
5461      }
5462  
5463      return rtrim( $url, '/' );
5464  }
5465  
5466  /**
5467   * Temporarily suspend cache additions.
5468   *
5469   * Stops more data being added to the cache, but still allows cache retrieval.
5470   * This is useful for actions, such as imports, when a lot of data would otherwise
5471   * be almost uselessly added to the cache.
5472   *
5473   * Suspension lasts for a single page load at most. Remember to call this
5474   * function again if you wish to re-enable cache adds earlier.
5475   *
5476   * @since 3.3.0
5477   *
5478   * @param bool $suspend Optional. Suspends additions if true, re-enables them if false.
5479   * @return bool The current suspend setting
5480   */
5481  function wp_suspend_cache_addition( $suspend = null ) {
5482      static $_suspend = false;
5483  
5484      if ( is_bool( $suspend ) ) {
5485          $_suspend = $suspend;
5486      }
5487  
5488      return $_suspend;
5489  }
5490  
5491  /**
5492   * Suspend cache invalidation.
5493   *
5494   * Turns cache invalidation on and off. Useful during imports where you don't want to do
5495   * invalidations every time a post is inserted. Callers must be sure that what they are
5496   * doing won't lead to an inconsistent cache when invalidation is suspended.
5497   *
5498   * @since 2.7.0
5499   *
5500   * @global bool $_wp_suspend_cache_invalidation
5501   *
5502   * @param bool $suspend Optional. Whether to suspend or enable cache invalidation. Default true.
5503   * @return bool The current suspend setting.
5504   */
5505  function wp_suspend_cache_invalidation( $suspend = true ) {
5506      global $_wp_suspend_cache_invalidation;
5507  
5508      $current_suspend                = $_wp_suspend_cache_invalidation;
5509      $_wp_suspend_cache_invalidation = $suspend;
5510      return $current_suspend;
5511  }
5512  
5513  /**
5514   * Determine whether a site is the main site of the current network.
5515   *
5516   * @since 3.0.0
5517   * @since 4.9.0 The `$network_id` parameter was added.
5518   *
5519   * @param int $site_id    Optional. Site ID to test. Defaults to current site.
5520   * @param int $network_id Optional. Network ID of the network to check for.
5521   *                        Defaults to current network.
5522   * @return bool True if $site_id is the main site of the network, or if not
5523   *              running Multisite.
5524   */
5525  function is_main_site( $site_id = null, $network_id = null ) {
5526      if ( ! is_multisite() ) {
5527          return true;
5528      }
5529  
5530      if ( ! $site_id ) {
5531          $site_id = get_current_blog_id();
5532      }
5533  
5534      $site_id = (int) $site_id;
5535  
5536      return get_main_site_id( $network_id ) === $site_id;
5537  }
5538  
5539  /**
5540   * Gets the main site ID.
5541   *
5542   * @since 4.9.0
5543   *
5544   * @param int $network_id Optional. The ID of the network for which to get the main site.
5545   *                        Defaults to the current network.
5546   * @return int The ID of the main site.
5547   */
5548  function get_main_site_id( $network_id = null ) {
5549      if ( ! is_multisite() ) {
5550          return get_current_blog_id();
5551      }
5552  
5553      $network = get_network( $network_id );
5554      if ( ! $network ) {
5555          return 0;
5556      }
5557  
5558      return $network->site_id;
5559  }
5560  
5561  /**
5562   * Determine whether a network is the main network of the Multisite installation.
5563   *
5564   * @since 3.7.0
5565   *
5566   * @param int $network_id Optional. Network ID to test. Defaults to current network.
5567   * @return bool True if $network_id is the main network, or if not running Multisite.
5568   */
5569  function is_main_network( $network_id = null ) {
5570      if ( ! is_multisite() ) {
5571          return true;
5572      }
5573  
5574      if ( null === $network_id ) {
5575          $network_id = get_current_network_id();
5576      }
5577  
5578      $network_id = (int) $network_id;
5579  
5580      return ( get_main_network_id() === $network_id );
5581  }
5582  
5583  /**
5584   * Get the main network ID.
5585   *
5586   * @since 4.3.0
5587   *
5588   * @return int The ID of the main network.
5589   */
5590  function get_main_network_id() {
5591      if ( ! is_multisite() ) {
5592          return 1;
5593      }
5594  
5595      $current_network = get_network();
5596  
5597      if ( defined( 'PRIMARY_NETWORK_ID' ) ) {
5598          $main_network_id = PRIMARY_NETWORK_ID;
5599      } elseif ( isset( $current_network->id ) && 1 === (int) $current_network->id ) {
5600          // If the current network has an ID of 1, assume it is the main network.
5601          $main_network_id = 1;
5602      } else {
5603          $_networks       = get_networks(
5604              array(
5605                  'fields' => 'ids',
5606                  'number' => 1,
5607              )
5608          );
5609          $main_network_id = array_shift( $_networks );
5610      }
5611  
5612      /**
5613       * Filters the main network ID.
5614       *
5615       * @since 4.3.0
5616       *
5617       * @param int $main_network_id The ID of the main network.
5618       */
5619      return (int) apply_filters( 'get_main_network_id', $main_network_id );
5620  }
5621  
5622  /**
5623   * Determine whether global terms are enabled.
5624   *
5625   * @since 3.0.0
5626   *
5627   * @return bool True if multisite and global terms enabled.
5628   */
5629  function global_terms_enabled() {
5630      if ( ! is_multisite() ) {
5631          return false;
5632      }
5633  
5634      static $global_terms = null;
5635      if ( is_null( $global_terms ) ) {
5636  
5637          /**
5638           * Filters whether global terms are enabled.
5639           *
5640           * Returning a non-null value from the filter will effectively short-circuit the function
5641           * and return the value of the 'global_terms_enabled' site option instead.
5642           *
5643           * @since 3.0.0
5644           *
5645           * @param null $enabled Whether global terms are enabled.
5646           */
5647          $filter = apply_filters( 'global_terms_enabled', null );
5648          if ( ! is_null( $filter ) ) {
5649              $global_terms = (bool) $filter;
5650          } else {
5651              $global_terms = (bool) get_site_option( 'global_terms_enabled', false );
5652          }
5653      }
5654      return $global_terms;
5655  }
5656  
5657  /**
5658   * Determines whether site meta is enabled.
5659   *
5660   * This function checks whether the 'blogmeta' database table exists. The result is saved as
5661   * a setting for the main network, making it essentially a global setting. Subsequent requests
5662   * will refer to this setting instead of running the query.
5663   *
5664   * @since 5.1.0
5665   *
5666   * @global wpdb $wpdb WordPress database abstraction object.
5667   *
5668   * @return bool True if site meta is supported, false otherwise.
5669   */
5670  function is_site_meta_supported() {
5671      global $wpdb;
5672  
5673      if ( ! is_multisite() ) {
5674          return false;
5675      }
5676  
5677      $network_id = get_main_network_id();
5678  
5679      $supported = get_network_option( $network_id, 'site_meta_supported', false );
5680      if ( false === $supported ) {
5681          $supported = $wpdb->get_var( "SHOW TABLES LIKE '{$wpdb->blogmeta}'" ) ? 1 : 0;
5682  
5683          update_network_option( $network_id, 'site_meta_supported', $supported );
5684      }
5685  
5686      return (bool) $supported;
5687  }
5688  
5689  /**
5690   * gmt_offset modification for smart timezone handling.
5691   *
5692   * Overrides the gmt_offset option if we have a timezone_string available.
5693   *
5694   * @since 2.8.0
5695   *
5696   * @return float|false Timezone GMT offset, false otherwise.
5697   */
5698  function wp_timezone_override_offset() {
5699      $timezone_string = get_option( 'timezone_string' );
5700      if ( ! $timezone_string ) {
5701          return false;
5702      }
5703  
5704      $timezone_object = timezone_open( $timezone_string );
5705      $datetime_object = date_create();
5706      if ( false === $timezone_object || false === $datetime_object ) {
5707          return false;
5708      }
5709      return round( timezone_offset_get( $timezone_object, $datetime_object ) / HOUR_IN_SECONDS, 2 );
5710  }
5711  
5712  /**
5713   * Sort-helper for timezones.
5714   *
5715   * @since 2.9.0
5716   * @access private
5717   *
5718   * @param array $a
5719   * @param array $b
5720   * @return int
5721   */
5722  function _wp_timezone_choice_usort_callback( $a, $b ) {
5723      // Don't use translated versions of Etc.
5724      if ( 'Etc' === $a['continent'] && 'Etc' === $b['continent'] ) {
5725          // Make the order of these more like the old dropdown.
5726          if ( 'GMT+' === substr( $a['city'], 0, 4 ) && 'GMT+' === substr( $b['city'], 0, 4 ) ) {
5727              return -1 * ( strnatcasecmp( $a['city'], $b['city'] ) );
5728          }
5729          if ( 'UTC' === $a['city'] ) {
5730              if ( 'GMT+' === substr( $b['city'], 0, 4 ) ) {
5731                  return 1;
5732              }
5733              return -1;
5734          }
5735          if ( 'UTC' === $b['city'] ) {
5736              if ( 'GMT+' === substr( $a['city'], 0, 4 ) ) {
5737                  return -1;
5738              }
5739              return 1;
5740          }
5741          return strnatcasecmp( $a['city'], $b['city'] );
5742      }
5743      if ( $a['t_continent'] == $b['t_continent'] ) {
5744          if ( $a['t_city'] == $b['t_city'] ) {
5745              return strnatcasecmp( $a['t_subcity'], $b['t_subcity'] );
5746          }
5747          return strnatcasecmp( $a['t_city'], $b['t_city'] );
5748      } else {
5749          // Force Etc to the bottom of the list.
5750          if ( 'Etc' === $a['continent'] ) {
5751              return 1;
5752          }
5753          if ( 'Etc' === $b['continent'] ) {
5754              return -1;
5755          }
5756          return strnatcasecmp( $a['t_continent'], $b['t_continent'] );
5757      }
5758  }
5759  
5760  /**
5761   * Gives a nicely-formatted list of timezone strings.
5762   *
5763   * @since 2.9.0
5764   * @since 4.7.0 Added the `$locale` parameter.
5765   *
5766   * @param string $selected_zone Selected timezone.
5767   * @param string $locale        Optional. Locale to load the timezones in. Default current site locale.
5768   * @return string
5769   */
5770  function wp_timezone_choice( $selected_zone, $locale = null ) {
5771      static $mo_loaded = false, $locale_loaded = null;
5772  
5773      $continents = array( 'Africa', 'America', 'Antarctica', 'Arctic', 'Asia', 'Atlantic', 'Australia', 'Europe', 'Indian', 'Pacific' );
5774  
5775      // Load translations for continents and cities.
5776      if ( ! $mo_loaded || $locale !== $locale_loaded ) {
5777          $locale_loaded = $locale ? $locale : get_locale();
5778          $mofile        = WP_LANG_DIR . '/continents-cities-' . $locale_loaded . '.mo';
5779          unload_textdomain( 'continents-cities' );
5780          load_textdomain( 'continents-cities', $mofile );
5781          $mo_loaded = true;
5782      }
5783  
5784      $zonen = array();
5785      foreach ( timezone_identifiers_list() as $zone ) {
5786          $zone = explode( '/', $zone );
5787          if ( ! in_array( $zone[0], $continents, true ) ) {
5788              continue;
5789          }
5790  
5791          // This determines what gets set and translated - we don't translate Etc/* strings here, they are done later.
5792          $exists    = array(
5793              0 => ( isset( $zone[0] ) && $zone[0] ),
5794              1 => ( isset( $zone[1] ) && $zone[1] ),
5795              2 => ( isset( $zone[2] ) && $zone[2] ),
5796          );
5797          $exists[3] = ( $exists[0] && 'Etc' !== $zone[0] );
5798          $exists[4] = ( $exists[1] && $exists[3] );
5799          $exists[5] = ( $exists[2] && $exists[3] );
5800  
5801          // phpcs:disable WordPress.WP.I18n.LowLevelTranslationFunction,WordPress.WP.I18n.NonSingularStringLiteralText
5802          $zonen[] = array(
5803              'continent'   => ( $exists[0] ? $zone[0] : '' ),
5804              'city'        => ( $exists[1] ? $zone[1] : '' ),
5805              'subcity'     => ( $exists[2] ? $zone[2] : '' ),
5806              't_continent' => ( $exists[3] ? translate( str_replace( '_', ' ', $zone[0] ), 'continents-cities' ) : '' ),
5807              't_city'      => ( $exists[4] ? translate( str_replace( '_', ' ', $zone[1] ), 'continents-cities' ) : '' ),
5808              't_subcity'   => ( $exists[5] ? translate( str_replace( '_', ' ', $zone[2] ), 'continents-cities' ) : '' ),
5809          );
5810          // phpcs:enable
5811      }
5812      usort( $zonen, '_wp_timezone_choice_usort_callback' );
5813  
5814      $structure = array();
5815  
5816      if ( empty( $selected_zone ) ) {
5817          $structure[] = '<option selected="selected" value="">' . __( 'Select a city' ) . '</option>';
5818      }
5819  
5820      foreach ( $zonen as $key => $zone ) {
5821          // Build value in an array to join later.
5822          $value = array( $zone['continent'] );
5823  
5824          if ( empty( $zone['city'] ) ) {
5825              // It's at the continent level (generally won't happen).
5826              $display = $zone['t_continent'];
5827          } else {
5828              // It's inside a continent group.
5829  
5830              // Continent optgroup.
5831              if ( ! isset( $zonen[ $key - 1 ] ) || $zonen[ $key - 1 ]['continent'] !== $zone['continent'] ) {
5832                  $label       = $zone['t_continent'];
5833                  $structure[] = '<optgroup label="' . esc_attr( $label ) . '">';
5834              }
5835  
5836              // Add the city to the value.
5837              $value[] = $zone['city'];
5838  
5839              $display = $zone['t_city'];
5840              if ( ! empty( $zone['subcity'] ) ) {
5841