ParagonIE_Sodium_Core_Base64_UrlSafe

9class ParagonIE_Sodium_Core_Base64_UrlSafe10{11    // COPY ParagonIE_Sodium_Core_Base64_Common STARTING HERE12    /**13     * Encode into Base6414     *15     * Base64 character set "[A-Z][a-z][0-9]+/"16     *17     * @param string $src18     * @return string19     * @throws TypeError20     */21    public static function encode($src)22    {23        return self::doEncode($src, true);24    }25 26    /**27     * Encode into Base64, no = padding28     *29     * Base64 character set "[A-Z][a-z][0-9]+/"30     *31     * @param string $src32     * @return string33     * @throws TypeError34     */35    public static function encodeUnpadded($src)36    {37        return self::doEncode($src, false);38    }39 40    /**41     * @param string $src42     * @param bool $pad   Include = padding?43     * @return string44     * @throws TypeError45     */46    protected static function doEncode($src, $pad = true)47    {48        $dest = '';49        $srcLen = ParagonIE_Sodium_Core_Util::strlen($src);50        // Main loop (no padding):51        for ($i = 0; $i + 3 <= $srcLen; $i += 3) {52            /** @var array<int, int> $chunk */53            $chunk = unpack('C*', ParagonIE_Sodium_Core_Util::substr($src, $i, 3));54            $b0 = $chunk[1];55            $b1 = $chunk[2];56            $b2 = $chunk[3];57 58            $dest .=59                self::encode6Bits(               $b0 >> 2       ) .60                self::encode6Bits((($b0 << 4) | ($b1 >> 4)) & 63) .61                self::encode6Bits((($b1 << 2) | ($b2 >> 6)) & 63) .62                self::encode6Bits(  $b2                     & 63);63        }64        // The last chunk, which may have padding:65        if ($i < $srcLen) {66            /** @var array<int, int> $chunk */67            $chunk = unpack('C*', ParagonIE_Sodium_Core_Util::substr($src, $i, $srcLen - $i));68            $b0 = $chunk[1];69            if ($i + 1 < $srcLen) {70                $b1 = $chunk[2];71                $dest .=72                    self::encode6Bits($b0 >> 2) .73                    self::encode6Bits((($b0 << 4) | ($b1 >> 4)) & 63) .74                    self::encode6Bits(($b1 << 2) & 63);75                if ($pad) {76                    $dest .= '=';77                }78            } else {79                $dest .=80                    self::encode6Bits( $b0 >> 2) .81                    self::encode6Bits(($b0 << 4) & 63);82                if ($pad) {83                    $dest .= '==';84                }85            }86        }87        return $dest;88    }