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   1  <?php
   2  /**
   3   * WordPress implementation for PHP functions either missing from older PHP versions or not included by default.
   4   *
   5   * This file is loaded extremely early and the functions can be relied upon by drop-ins.
   6   * Ergo, please ensure you do not rely on external functions when writing code for this file.
   7   * Only use functions built into PHP or are defined in this file and have adequate testing
   8   * and error suppression to ensure the file will run correctly and not break websites.
   9   *
  10   * @package PHP
  11   * @access private
  12   */
  13  
  14  // If gettext isn't available.
  15  if ( ! function_exists( '_' ) ) {
  16      /**
  17       * Compat function to mimic _(), an alias of gettext().
  18       *
  19       * @since 0.71
  20       *
  21       * @see https://php.net/manual/en/function.gettext.php
  22       *
  23       * @param string $message The message being translated.
  24       * @return string
  25       */
  26      function _( $message ) {
  27          return $message;
  28      }
  29  }
  30  
  31  /**
  32   * Returns whether PCRE/u (PCRE_UTF8 modifier) is available for use.
  33   *
  34   * @ignore
  35   * @since 4.2.2
  36   * @since 6.9.0 Deprecated the `$set` argument.
  37   * @access private
  38   *
  39   * @param bool $set Deprecated. This argument is no longer used for testing purposes.
  40   */
  41  function _wp_can_use_pcre_u( $set = null ) {
  42      static $utf8_pcre = null;
  43  
  44      if ( isset( $set ) ) {
  45          _deprecated_argument( __FUNCTION__, '6.9.0' );
  46      }
  47  
  48      if ( isset( $utf8_pcre ) ) {
  49          return $utf8_pcre;
  50      }
  51  
  52      $utf8_pcre = true;
  53      set_error_handler(
  54          function ( $errno, $errstr ) use ( &$utf8_pcre ) {
  55              if ( str_starts_with( $errstr, 'preg_match():' ) ) {
  56                  $utf8_pcre = false;
  57                  return true;
  58              }
  59  
  60              return false;
  61          },
  62          E_WARNING
  63      );
  64  
  65      /*
  66       * Attempt to compile a PCRE pattern with the PCRE_UTF8 flag. For
  67       * systems lacking Unicode support this will trigger a warning
  68       * during compilation, which the error handler will intercept.
  69       */
  70      preg_match( '//u', '' );
  71      restore_error_handler();
  72  
  73      return $utf8_pcre;
  74  }
  75  
  76  /**
  77   * Indicates if a given slug for a character set represents the UTF-8 text encoding.
  78   *
  79   * A charset is considered to represent UTF-8 if it is a case-insensitive match
  80   * of "UTF-8" with or without the hyphen.
  81   *
  82   * Example:
  83   *
  84   *     true  === _is_utf8_charset( 'UTF-8' );
  85   *     true  === _is_utf8_charset( 'utf8' );
  86   *     false === _is_utf8_charset( 'latin1' );
  87   *     false === _is_utf8_charset( 'UTF 8' );
  88   *
  89   *     // Only strings match.
  90   *     false === _is_utf8_charset( [ 'charset' => 'utf-8' ] );
  91   *
  92   * `is_utf8_charset` should be used outside of this file.
  93   *
  94   * @ignore
  95   * @since 6.6.1
  96   *
  97   * @param string $charset_slug Slug representing a text character encoding, or "charset".
  98   *                             E.g. "UTF-8", "Windows-1252", "ISO-8859-1", "SJIS".
  99   *
 100   * @return bool Whether the slug represents the UTF-8 encoding.
 101   */
 102  function _is_utf8_charset( $charset_slug ) {
 103      if ( ! is_string( $charset_slug ) ) {
 104          return false;
 105      }
 106  
 107      return (
 108          0 === strcasecmp( 'UTF-8', $charset_slug ) ||
 109          0 === strcasecmp( 'UTF8', $charset_slug )
 110      );
 111  }
 112  
 113  if ( ! function_exists( 'mb_substr' ) ) :
 114      /**
 115       * Compat function to mimic mb_substr().
 116       *
 117       * @ignore
 118       * @since 3.2.0
 119       *
 120       * @see _mb_substr()
 121       *
 122       * @param string      $string   The string to extract the substring from.
 123       * @param int         $start    Position to being extraction from in `$string`.
 124       * @param int|null    $length   Optional. Maximum number of characters to extract from `$string`.
 125       *                              Default null.
 126       * @param string|null $encoding Optional. Character encoding to use. Default null.
 127       * @return string Extracted substring.
 128       */
 129  	function mb_substr( $string, $start, $length = null, $encoding = null ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.stringFound
 130          return _mb_substr( $string, $start, $length, $encoding );
 131      }
 132  endif;
 133  
 134  /**
 135   * Internal compat function to mimic mb_substr().
 136   *
 137   * Only supports UTF-8 and non-shifting single-byte encodings. For all other encodings
 138   * expect the substrings to be misaligned. When the given encoding (or the `blog_charset`
 139   * if none is provided) isn’t UTF-8 then the function returns the output of {@see \substr()}.
 140   *
 141   * @ignore
 142   * @since 3.2.0
 143   *
 144   * @param string      $str      The string to extract the substring from.
 145   * @param int         $start    Character offset at which to start the substring extraction.
 146   * @param int|null    $length   Optional. Maximum number of characters to extract from `$str`.
 147   *                              Default null.
 148   * @param string|null $encoding Optional. Character encoding to use. Default null.
 149   * @return string Extracted substring.
 150   */
 151  function _mb_substr( $str, $start, $length = null, $encoding = null ) {
 152      if ( null === $str ) {
 153          return '';
 154      }
 155  
 156      // The solution below works only for UTF-8; treat all other encodings as byte streams.
 157      if ( ! _is_utf8_charset( $encoding ?? get_option( 'blog_charset' ) ) ) {
 158          return is_null( $length ) ? substr( $str, $start ) : substr( $str, $start, $length );
 159      }
 160  
 161      $total_length = ( $start < 0 || $length < 0 )
 162          ? _wp_utf8_codepoint_count( $str )
 163          : 0;
 164  
 165      $normalized_start = $start < 0
 166          ? max( 0, $total_length + $start )
 167          : $start;
 168  
 169      /*
 170       * The starting offset is provided as characters, which means this needs to
 171       * find how many bytes that many characters occupies at the start of the string.
 172       */
 173      $starting_byte_offset = _wp_utf8_codepoint_span( $str, 0, $normalized_start );
 174  
 175      $normalized_length = $length < 0
 176          ? max( 0, $total_length - $normalized_start + $length )
 177          : $length;
 178  
 179      /*
 180       * This is the main step. It finds how many bytes the given length of code points
 181       * occupies in the input, starting at the byte offset calculated above.
 182       */
 183      $byte_length = isset( $normalized_length )
 184          ? _wp_utf8_codepoint_span( $str, $starting_byte_offset, $normalized_length )
 185          : ( strlen( $str ) - $starting_byte_offset );
 186  
 187      // The result is a normal byte-level substring using the computed ranges.
 188      return substr( $str, $starting_byte_offset, $byte_length );
 189  }
 190  
 191  if ( ! function_exists( 'mb_strlen' ) ) :
 192      /**
 193       * Compat function to mimic mb_strlen().
 194       *
 195       * @ignore
 196       * @since 4.2.0
 197       *
 198       * @see _mb_strlen()
 199       *
 200       * @param string      $string   The string to retrieve the character length from.
 201       * @param string|null $encoding Optional. Character encoding to use. Default null.
 202       * @return int String length of `$string`.
 203       */
 204  	function mb_strlen( $string, $encoding = null ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.stringFound
 205          return _mb_strlen( $string, $encoding );
 206      }
 207  endif;
 208  
 209  /**
 210   * Internal compat function to mimic mb_strlen().
 211   *
 212   * Only supports UTF-8 and non-shifting single-byte encodings. For all other
 213   * encodings expect the counts to be wrong. When the given encoding (or the
 214   * `blog_charset` if none is provided) isn’t UTF-8 then the function returns
 215   * the byte-count of the provided string.
 216   *
 217   * @ignore
 218   * @since 4.2.0
 219   *
 220   * @param string      $str      The string to retrieve the character length from.
 221   * @param string|null $encoding Optional. Count characters according to this encoding.
 222   *                              Default is to consult `blog_charset`.
 223   * @return int Count of code points if UTF-8, byte length otherwise.
 224   */
 225  function _mb_strlen( $str, $encoding = null ) {
 226      return _is_utf8_charset( $encoding ?? get_option( 'blog_charset' ) )
 227          ? _wp_utf8_codepoint_count( $str )
 228          : strlen( $str );
 229  }
 230  
 231  if ( ! function_exists( 'utf8_encode' ) ) :
 232      if ( extension_loaded( 'mbstring' ) ) :
 233          /**
 234           * Converts a string from ISO-8859-1 to UTF-8.
 235           *
 236           * @deprecated Use {@see \mb_convert_encoding()} instead.
 237           *
 238           * @since 6.9.0
 239           *
 240           * @param string $iso_8859_1_text Text treated as ISO-8859-1 (latin1) bytes.
 241           * @return string Text converted into a UTF-8.
 242           */
 243  		function utf8_encode( $iso_8859_1_text ): string {
 244              _deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );
 245  
 246              return mb_convert_encoding( $iso_8859_1_text, 'UTF-8', 'ISO-8859-1' );
 247          }
 248  
 249      else :
 250          /**
 251           * @ignore
 252           * @private
 253           *
 254           * @since 6.9.0
 255           */
 256  		function utf8_encode( $iso_8859_1_text ): string {
 257              _deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );
 258  
 259              return _wp_utf8_encode_fallback( $iso_8859_1_text );
 260          }
 261  
 262      endif;
 263  endif;
 264  
 265  if ( ! function_exists( 'utf8_decode' ) ) :
 266      if ( extension_loaded( 'mbstring' ) ) :
 267          /**
 268           * Converts a string from UTF-8 to ISO-8859-1.
 269           *
 270           * @deprecated Use {@see \mb_convert_encoding()} instead.
 271           *
 272           * @since 6.9.0
 273           *
 274           * @param string $utf8_text Text treated as UTF-8.
 275           * @return string Text converted into ISO-8859-1.
 276           */
 277  		function utf8_decode( $utf8_text ): string {
 278              _deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );
 279  
 280              return mb_convert_encoding( $utf8_text, 'ISO-8859-1', 'UTF-8' );
 281          }
 282  
 283      else :
 284          /**
 285           * @ignore
 286           * @private
 287           *
 288           * @since 6.9.0
 289           */
 290  		function utf8_decode( $utf8_text ): string {
 291              _deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );
 292  
 293              return _wp_utf8_decode_fallback( $utf8_text );
 294          }
 295  
 296      endif;
 297  endif;
 298  
 299  // sodium_crypto_box() was introduced in PHP 7.2.
 300  if ( ! function_exists( 'sodium_crypto_box' ) ) {
 301      require  ABSPATH . WPINC . '/sodium_compat/autoload.php';
 302  }
 303  
 304  if ( ! function_exists( 'is_countable' ) ) {
 305      /**
 306       * Polyfill for is_countable() function added in PHP 7.3.
 307       *
 308       * Verify that the content of a variable is an array or an object
 309       * implementing the Countable interface.
 310       *
 311       * @since 4.9.6
 312       *
 313       * @param mixed $value The value to check.
 314       * @return bool True if `$value` is countable, false otherwise.
 315       */
 316  	function is_countable( $value ) {
 317          return ( is_array( $value )
 318              || $value instanceof Countable
 319              || $value instanceof SimpleXMLElement
 320              || $value instanceof ResourceBundle
 321          );
 322      }
 323  }
 324  
 325  if ( ! function_exists( 'array_key_first' ) ) {
 326      /**
 327       * Polyfill for array_key_first() function added in PHP 7.3.
 328       *
 329       * Get the first key of the given array without affecting
 330       * the internal array pointer.
 331       *
 332       * @since 5.9.0
 333       *
 334       * @param array $array An array.
 335       * @return string|int|null The first key of array if the array
 336       *                         is not empty; `null` otherwise.
 337       */
 338  	function array_key_first( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
 339          if ( empty( $array ) ) {
 340              return null;
 341          }
 342  
 343          foreach ( $array as $key => $value ) {
 344              return $key;
 345          }
 346      }
 347  }
 348  
 349  if ( ! function_exists( 'array_key_last' ) ) {
 350      /**
 351       * Polyfill for `array_key_last()` function added in PHP 7.3.
 352       *
 353       * Get the last key of the given array without affecting the
 354       * internal array pointer.
 355       *
 356       * @since 5.9.0
 357       *
 358       * @param array $array An array.
 359       * @return string|int|null The last key of array if the array
 360       *.                        is not empty; `null` otherwise.
 361       */
 362  	function array_key_last( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
 363          if ( empty( $array ) ) {
 364              return null;
 365          }
 366  
 367          end( $array );
 368  
 369          return key( $array );
 370      }
 371  }
 372  
 373  if ( ! function_exists( 'array_is_list' ) ) {
 374      /**
 375       * Polyfill for `array_is_list()` function added in PHP 8.1.
 376       *
 377       * Determines if the given array is a list.
 378       *
 379       * An array is considered a list if its keys consist of consecutive numbers from 0 to count($array)-1.
 380       *
 381       * @see https://github.com/symfony/polyfill-php81/tree/main
 382       *
 383       * @since 6.5.0
 384       *
 385       * @param array<mixed> $arr The array being evaluated.
 386       * @return bool True if array is a list, false otherwise.
 387       */
 388  	function array_is_list( $arr ) {
 389          if ( ( array() === $arr ) || ( array_values( $arr ) === $arr ) ) {
 390              return true;
 391          }
 392  
 393          $next_key = -1;
 394  
 395          foreach ( $arr as $k => $v ) {
 396              if ( ++$next_key !== $k ) {
 397                  return false;
 398              }
 399          }
 400  
 401          return true;
 402      }
 403  }
 404  
 405  if ( ! function_exists( 'str_contains' ) ) {
 406      /**
 407       * Polyfill for `str_contains()` function added in PHP 8.0.
 408       *
 409       * Performs a case-sensitive check indicating if needle is
 410       * contained in haystack.
 411       *
 412       * @since 5.9.0
 413       *
 414       * @param string $haystack The string to search in.
 415       * @param string $needle   The substring to search for in the `$haystack`.
 416       * @return bool True if `$needle` is in `$haystack`, otherwise false.
 417       */
 418  	function str_contains( $haystack, $needle ) {
 419          if ( '' === $needle ) {
 420              return true;
 421          }
 422  
 423          return false !== strpos( $haystack, $needle );
 424      }
 425  }
 426  
 427  if ( ! function_exists( 'str_starts_with' ) ) {
 428      /**
 429       * Polyfill for `str_starts_with()` function added in PHP 8.0.
 430       *
 431       * Performs a case-sensitive check indicating if
 432       * the haystack begins with needle.
 433       *
 434       * @since 5.9.0
 435       *
 436       * @param string $haystack The string to search in.
 437       * @param string $needle   The substring to search for in the `$haystack`.
 438       * @return bool True if `$haystack` starts with `$needle`, otherwise false.
 439       */
 440  	function str_starts_with( $haystack, $needle ) {
 441          if ( '' === $needle ) {
 442              return true;
 443          }
 444  
 445          return 0 === strpos( $haystack, $needle );
 446      }
 447  }
 448  
 449  if ( ! function_exists( 'str_ends_with' ) ) {
 450      /**
 451       * Polyfill for `str_ends_with()` function added in PHP 8.0.
 452       *
 453       * Performs a case-sensitive check indicating if
 454       * the haystack ends with needle.
 455       *
 456       * @since 5.9.0
 457       *
 458       * @param string $haystack The string to search in.
 459       * @param string $needle   The substring to search for in the `$haystack`.
 460       * @return bool True if `$haystack` ends with `$needle`, otherwise false.
 461       */
 462  	function str_ends_with( $haystack, $needle ) {
 463          if ( '' === $haystack ) {
 464              return '' === $needle;
 465          }
 466  
 467          $len = strlen( $needle );
 468  
 469          return substr( $haystack, -$len, $len ) === $needle;
 470      }
 471  }
 472  
 473  if ( ! function_exists( 'array_find' ) ) {
 474      /**
 475       * Polyfill for `array_find()` function added in PHP 8.4.
 476       *
 477       * Searches an array for the first element that passes a given callback.
 478       *
 479       * @since 6.8.0
 480       *
 481       * @param array    $array    The array to search.
 482       * @param callable $callback The callback to run for each element.
 483       * @return mixed|null The first element in the array that passes the `$callback`, otherwise null.
 484       */
 485  	function array_find( array $array, callable $callback ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
 486          foreach ( $array as $key => $value ) {
 487              if ( $callback( $value, $key ) ) {
 488                  return $value;
 489              }
 490          }
 491  
 492          return null;
 493      }
 494  }
 495  
 496  if ( ! function_exists( 'array_find_key' ) ) {
 497      /**
 498       * Polyfill for `array_find_key()` function added in PHP 8.4.
 499       *
 500       * Searches an array for the first key that passes a given callback.
 501       *
 502       * @since 6.8.0
 503       *
 504       * @param array    $array    The array to search.
 505       * @param callable $callback The callback to run for each element.
 506       * @return int|string|null The first key in the array that passes the `$callback`, otherwise null.
 507       */
 508  	function array_find_key( array $array, callable $callback ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
 509          foreach ( $array as $key => $value ) {
 510              if ( $callback( $value, $key ) ) {
 511                  return $key;
 512              }
 513          }
 514  
 515          return null;
 516      }
 517  }
 518  
 519  if ( ! function_exists( 'array_any' ) ) {
 520      /**
 521       * Polyfill for `array_any()` function added in PHP 8.4.
 522       *
 523       * Checks if any element of an array passes a given callback.
 524       *
 525       * @since 6.8.0
 526       *
 527       * @param array    $array    The array to check.
 528       * @param callable $callback The callback to run for each element.
 529       * @return bool True if any element in the array passes the `$callback`, otherwise false.
 530       */
 531  	function array_any( array $array, callable $callback ): bool { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
 532          foreach ( $array as $key => $value ) {
 533              if ( $callback( $value, $key ) ) {
 534                  return true;
 535              }
 536          }
 537  
 538          return false;
 539      }
 540  }
 541  
 542  if ( ! function_exists( 'array_all' ) ) {
 543      /**
 544       * Polyfill for `array_all()` function added in PHP 8.4.
 545       *
 546       * Checks if all elements of an array pass a given callback.
 547       *
 548       * @since 6.8.0
 549       *
 550       * @param array    $array    The array to check.
 551       * @param callable $callback The callback to run for each element.
 552       * @return bool True if all elements in the array pass the `$callback`, otherwise false.
 553       */
 554  	function array_all( array $array, callable $callback ): bool { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
 555          foreach ( $array as $key => $value ) {
 556              if ( ! $callback( $value, $key ) ) {
 557                  return false;
 558              }
 559          }
 560  
 561          return true;
 562      }
 563  }
 564  
 565  if ( ! function_exists( 'array_first' ) ) {
 566      /**
 567       * Polyfill for `array_first()` function added in PHP 8.5.
 568       *
 569       * Returns the first element of an array.
 570       *
 571       * @since 6.9.0
 572       *
 573       * @param array $array The array to get the first element from.
 574       * @return mixed|null The first element of the array, or null if the array is empty.
 575       */
 576  	function array_first( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
 577          if ( empty( $array ) ) {
 578              return null;
 579          }
 580  
 581          foreach ( $array as $value ) {
 582              return $value;
 583          }
 584      }
 585  }
 586  
 587  if ( ! function_exists( 'array_last' ) ) {
 588      /**
 589       * Polyfill for `array_last()` function added in PHP 8.5.
 590       *
 591       * Returns the last element of an array.
 592       *
 593       * @since 6.9.0
 594       *
 595       * @param array $array The array to get the last element from.
 596       * @return mixed|null The last element of the array, or null if the array is empty.
 597       */
 598  	function array_last( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
 599          if ( empty( $array ) ) {
 600              return null;
 601          }
 602  
 603          return $array[ array_key_last( $array ) ];
 604      }
 605  }
 606  
 607  // IMAGETYPE_AVIF constant is only defined in PHP 8.x or later.
 608  if ( ! defined( 'IMAGETYPE_AVIF' ) ) {
 609      define( 'IMAGETYPE_AVIF', 19 );
 610  }
 611  
 612  // IMG_AVIF constant is only defined in PHP 8.x or later.
 613  if ( ! defined( 'IMG_AVIF' ) ) {
 614      define( 'IMG_AVIF', IMAGETYPE_AVIF );
 615  }
 616  
 617  // IMAGETYPE_HEIC constant is not yet defined in PHP as of PHP 8.3.
 618  if ( ! defined( 'IMAGETYPE_HEIC' ) ) {
 619      define( 'IMAGETYPE_HEIC', 99 );
 620  }