Function hex_encode

webrtc/base/stringencode.cc:413–416

static const char HEX[] = "0123456789abcdef";

char hex_encode(unsigned char val) {
  RTC_DCHECK_LT(val, 16);
  return (val < 16) ? HEX[val] : '!';
}

bool hex_decode(char ch, unsigned char* val) {
  if ((ch >= '0') && (ch <= '9')) {