voku\helper\UTF8::is_utf8()

Complexity

Conditions	25
Paths	29

Size

Total Lines	134
Code Lines	69

Duplication

Lines	21
Ratio	15.67 %

Code Coverage

Tests	60
CRAP Score	25.1525

Importance

Changes	5
Bugs	0	Features	3

<?php
  public static function is_utf8($str, $strict = false)
  {
    $str = (string)$str;

    if (!isset($str[0])) {
      return true;
    }

    if ($strict === true) {
      if (self::is_utf16($str) !== false) {
        return false;
      }

      if (self::is_utf32($str) !== false) {
        return false;
      }
    }

    if (self::pcre_utf8_support() !== true) {

      // If even just the first character can be matched, when the /u
      // modifier is used, then it's valid UTF-8. If the UTF-8 is somehow
      // invalid, nothing at all will match, even if the string contains
      // some valid sequences
      return (preg_match('/^.{1}/us', $str, $ar) === 1);

    } else {

      $mState = 0; // cached expected number of octets after the current octet
      // until the beginning of the next UTF8 character sequence
      $mUcs4 = 0; // cached Unicode character
      $mBytes = 1; // cached expected number of octets in the current sequence
      $len = strlen($str);

      /** @noinspection ForeachInvariantsInspection */
      for ($i = 0; $i < $len; $i++) {
        $in = ord($str[$i]);
        if ($mState === 0) {
          // When mState is zero we expect either a US-ASCII character or a
          // multi-octet sequence.
          if (0 === (0x80 & $in)) {
            // US-ASCII, pass straight through.
            $mBytes = 1;
          } elseif (0xC0 === (0xE0 & $in)) {

This code seems to be duplicated across your project.

            // First octet of 2 octet sequence.
            $mUcs4 = $in;
            $mUcs4 = ($mUcs4 & 0x1F) << 6;
            $mState = 1;
            $mBytes = 2;
          } elseif (0xE0 === (0xF0 & $in)) {
            // First octet of 3 octet sequence.
            $mUcs4 = $in;
            $mUcs4 = ($mUcs4 & 0x0F) << 12;
            $mState = 2;
            $mBytes = 3;
          } elseif (0xF0 === (0xF8 & $in)) {

This code seems to be duplicated across your project.

            // First octet of 4 octet sequence.
            $mUcs4 = $in;
            $mUcs4 = ($mUcs4 & 0x07) << 18;
            $mState = 3;
            $mBytes = 4;
          } elseif (0xF8 === (0xFC & $in)) {
            /* First octet of 5 octet sequence.
            *
            * This is illegal because the encoded codepoint must be either
            * (a) not the shortest form or
            * (b) outside the Unicode range of 0-0x10FFFF.
            * Rather than trying to resynchronize, we will carry on until the end
            * of the sequence and let the later error handling code catch it.
            */
            $mUcs4 = $in;
            $mUcs4 = ($mUcs4 & 0x03) << 24;
            $mState = 4;
            $mBytes = 5;
          } elseif (0xFC === (0xFE & $in)) {

This code seems to be duplicated across your project.

            // First octet of 6 octet sequence, see comments for 5 octet sequence.
            $mUcs4 = $in;
            $mUcs4 = ($mUcs4 & 1) << 30;
            $mState = 5;
            $mBytes = 6;
          } else {
            /* Current octet is neither in the US-ASCII range nor a legal first
             * octet of a multi-octet sequence.
             */
            return false;
          }
        } else {
          // When mState is non-zero, we expect a continuation of the multi-octet
          // sequence
          if (0x80 === (0xC0 & $in)) {
            // Legal continuation.
            $shift = ($mState - 1) * 6;
            $tmp = $in;
            $tmp = ($tmp & 0x0000003F) << $shift;
            $mUcs4 |= $tmp;
            /**
             * End of the multi-octet sequence. mUcs4 now contains the final
             * Unicode code point to be output
             */
            if (0 === --$mState) {
              /*
              * Check for illegal sequences and code points.
              */
              // From Unicode 3.1, non-shortest form is illegal
              if (
                  (2 === $mBytes && $mUcs4 < 0x0080) ||
                  (3 === $mBytes && $mUcs4 < 0x0800) ||
                  (4 === $mBytes && $mUcs4 < 0x10000) ||
                  (4 < $mBytes) ||
                  // From Unicode 3.2, surrogate characters are illegal.
                  (($mUcs4 & 0xFFFFF800) === 0xD800) ||
                  // Code points outside the Unicode range are illegal.
                  ($mUcs4 > 0x10FFFF)
              ) {
                return false;
              }
              // initialize UTF8 cache
              $mState = 0;
              $mUcs4 = 0;
              $mBytes = 1;
            }
          } else {
            /**
             *((0xC0 & (*in) != 0x80) && (mState != 0))
             * Incomplete multi-octet sequence.
             */
            return false;
          }
        }
      }

      return true;
    }
  }