S_QUOTE
if (str[0] == S_QUOTE
&& str[2] == S_QUOTE) {
buffer[bufp++] = S_QUOTE;
|| ch == S_QUOTE)
buffer[bufp++] = S_QUOTE;
case S_QUOTE:
case S_QUOTE:
*d++ = S_QUOTE;
*d++ = S_QUOTE;