5.x PHPMailer.php

public PHPMailer::utf8CharBoundary($encodedText, $maxLength)

Find the last character boundary prior to $maxLength in a utf-8 quoted-printable encoded string. Original written by Colin Brown.

Parameters

string $encodedText utf-8 QP text:

int $maxLength Find the last character boundary prior to this length:

Return value

int

File

inc/PHPMailer/src/PHPMailer.php, line 2256

Class

PHPMailer

PHPMailer - PHP email creation and transport class.

Namespace

PHPMailer\PHPMailer

Code

public function utf8CharBoundary($encodedText, $maxLength) 
 {
  $foundSplitPos = false;
  $lookBack = 3;
  while (!$foundSplitPos) {
    $lastChunk = substr($encodedText, $maxLength - $lookBack, $lookBack);
    $encodedCharPos = strpos($lastChunk, '=');
    if (false !== $encodedCharPos) {
      // Found start of encoded character byte within $lookBack block.
      // Check the encoded byte value (the 2 chars after the '=')
      $hex = substr($encodedText, $maxLength - $lookBack + $encodedCharPos + 1, 2);
      $dec = hexdec($hex);
      if ($dec < 128) {
        // Single byte character.
        // If the encoded char was found at pos 0, it will fit
        // otherwise reduce maxLength to start of the encoded char
        if ($encodedCharPos > 0) {
          $maxLength -= $lookBack - $encodedCharPos;
        }
        $foundSplitPos = true;
      }
      elseif ($dec >= 192) {
        // First byte of a multi byte character
        // Reduce maxLength to split at start of character
        $maxLength -= $lookBack - $encodedCharPos;
        $foundSplitPos = true;
      }
      elseif ($dec < 192) {
        // Middle byte of a multi byte character, look further back
        $lookBack += 3;
      }
    }
    else {
      // No encoded character found
      $foundSplitPos = true;
    }
  }

  return $maxLength;
}