calc_first (dfa, node);
if (node->next == -1)
calc_next (dfa, node);
- if (node->eclosure.nelem == 0)
- calc_epsdest (dfa, node);
+ calc_epsdest (dfa, node);
+
/* Calculate "first" etc. for the left child. */
if (node->left != NULL)
{
for (idx = 0; idx < dfa->eclosures[src].nelem; ++idx)
{
dest = dfa->eclosures[src].elems[idx];
- re_node_set_insert (dfa->inveclosures + dest, src);
+ re_node_set_insert_last (dfa->inveclosures + dest, src);
}
}
}
reg_errcode_t *err;
{
re_token_t dup_token;
- bin_tree_t *tree = NULL;
+ bin_tree_t *tree = NULL, *old_tree = NULL;
int i, start, end, start_idx = re_string_cur_idx (regexp);
re_token_t start_token = *token;
end = (token->type == OP_DUP_QUESTION) ? 1 : -1;
}
+ fetch_token (token, regexp, syntax);
+
/* Treat "<re>{0}*" etc. as "<re>{0}". */
- if (BE (elem == NULL, 0))
- start = end = 0;
+ if (BE (elem == NULL || (start == 0 && end == 0), 0))
+ return NULL;
/* Extract "<re>{n,m}" to "<re><re>...<re><re>{0,<m-n>}". */
- else if (BE (start > 0, 0))
+ if (BE (start > 0, 0))
{
tree = elem;
for (i = 2; i <= start; ++i)
if (BE (elem == NULL || tree == NULL, 0))
goto parse_dup_op_espace;
}
- }
- if (BE (end != start, 1))
- {
- dup_token.type = (end == -1 ? OP_DUP_ASTERISK : OP_DUP_QUESTION);
- if (BE (start > 0, 0))
- {
- elem = duplicate_tree (elem, dfa);
- if (BE (elem == NULL, 0))
- goto parse_dup_op_espace;
+ if (start == end)
+ return tree;
- /* This subexpression will be marked as optional, so that
- empty matches do not touch the registers. */
- mark_opt_subexp (elem, dfa);
+ /* Duplicate ELEM before it is marked optional. */
+ elem = duplicate_tree (elem, dfa);
+ old_tree = tree;
+ }
+ else
+ old_tree = NULL;
- /* Prepare the tree with the modifier. */
- elem = re_dfa_add_tree_node (dfa, elem, NULL, &dup_token);
- tree = create_tree (dfa, tree, elem, CONCAT, 0);
- }
- else
- {
- /* We do not need to duplicate the tree because we have not
- created it yet. */
- mark_opt_subexp (elem, dfa);
- tree = elem = re_dfa_add_tree_node (dfa, elem, NULL, &dup_token);
- }
+ mark_opt_subexp (elem, dfa);
+ dup_token.type = (end == -1 ? OP_DUP_ASTERISK : OP_DUP_QUESTION);
+ tree = re_dfa_add_tree_node (dfa, elem, NULL, &dup_token);
+ if (BE (tree == NULL, 0))
+ goto parse_dup_op_espace;
+ /* This loop is actually executed only when end != -1,
+ to rewrite <re>{0,n} as (<re>(<re>...<re>?)?)?... We have
+ already created the start+1-th copy. */
+ for (i = start + 2; i <= end; ++i)
+ {
+ elem = duplicate_tree (elem, dfa);
+ tree = create_tree (dfa, tree, elem, CONCAT, 0);
if (BE (elem == NULL || tree == NULL, 0))
goto parse_dup_op_espace;
- /* This loop is actually executed only when end != -1,
- to rewrite <re>{0,n} as <re>?<re>?<re>?... We have
- already created the start+1-th copy. */
- for (i = start + 2; i <= end; ++i)
- {
- elem = duplicate_tree (elem, dfa);
- tree = create_tree (dfa, tree, elem, CONCAT, 0);
- if (BE (elem == NULL || tree == NULL, 0))
- {
- *err = REG_ESPACE;
- return NULL;
- }
- }
+ tree = re_dfa_add_tree_node (dfa, tree, NULL, &dup_token);
+ if (BE (tree == NULL, 0))
+ goto parse_dup_op_espace;
}
- fetch_token (token, regexp, syntax);
+ if (old_tree)
+ tree = create_tree (dfa, old_tree, tree, CONCAT, 0);
+
return tree;
parse_dup_op_espace: