Function tok822_parse_limit

lib_acl_cpp/src/mime/internal/tok822_parse.cpp:483–567

/* tok822_parse_limit - translate external string to token tree */

TOK822 *tok822_parse_limit(const char *str, int tok_count_limit)
{
	TOK822 *head;
	TOK822 *tail;
	TOK822 *right;
	TOK822 *first_token;
	TOK822 *last_token;
	TOK822 *tp;
	int     state;

	/*
	 * First, tokenize the string, from left to right. We are not allowed to
	 * throw away any information that we do not understand. With a flat
	 * token list that contains all tokens, we can always convert back to
	 * string form.
	 */
	if ((first_token = tok822_scan_limit(str, &last_token, tok_count_limit)) == 0)
		return (0);

	/*
	 * For convenience, sandwich the token list between two sentinel tokens.
	 */
#define GLUE(left,rite) { left->next = rite; rite->prev = left; }

	head = tok822_alloc(0, (char *) 0);
	GLUE(head, first_token);
	tail = tok822_alloc(0, (char *) 0);
	GLUE(last_token, tail);

	/*
	 * Next step is to transform the token list into a parse tree. This is
	 * done most conveniently from right to left. If there is something that
	 * we do not understand, just leave it alone, don't throw it away. The
	 * address information that we're looking for sits in-between the current
	 * node (tp) and the one called right. Add missing commas on the fly.
	 */
	state = DO_WORD;
	right = tail;
	tp = tail->prev;
	while (tp->type) {
		if (tp->type == TOK822_COMMENT) {	/* move comment to the side */
			MOVE_COMMENT_AND_CONTINUE(tp, right);
		} else if (tp->type == ';') {		/* rh side of named group */
			right = tok822_group(TOK822_ADDR, tp, right, ADD_COMMA);
			state = DO_GROUP | DO_WORD;
		} else if (tp->type == ':' && (state & DO_GROUP) != 0) {
			tp->type = TOK822_STARTGRP;
			(void) tok822_group(TOK822_ADDR, tp, right, NO_MISSING_COMMA);
			SKIP(tp, tp->type != ',');
			right = tp;
			continue;
		} else if (tp->type == '>') {		/* rh side of <route> */
			right = tok822_group(TOK822_ADDR, tp, right, ADD_COMMA);
			SKIP_MOVE_COMMENT(tp, tp->type != '<', right);
			(void) tok822_group(TOK822_ADDR, tp, right, NO_MISSING_COMMA);
			SKIP(tp, tp->type > 0xff || strchr(">;,:", tp->type) == 0);
			right = tp;
			state |= DO_WORD;