static Bool
da_enumerate_recursive (const DArray *d,
TrieIndex state,
DAEnumFunc enum_func,
void *user_data)
{
Bool ret;
TrieIndex base;
base = da_get_base (d, state);
if (base < 0) {
TrieChar *key;
key = da_get_state_key (d, state);
ret = (*enum_func) (key, state, user_data);
free (key);
} else {
Symbols *symbols;
int i;
ret = TRUE;
symbols = da_output_symbols (d, state);
for (i = 0; ret && i < symbols_num (symbols); i++) {
ret = da_enumerate_recursive (d, base + symbols_get (symbols, i),
enum_func, user_data);
}
symbols_free (symbols);
}
return ret;
}
/**
* @brief Get all walkable characters from state
*
* @param s : the state to get
* @param chars : the storage for the result
* @param chars_nelm : the size of @a chars[] in number of elements
*
* @return total walkable characters
*
* Get the list of all walkable characters from state @a s. At most
* @a chars_nelm walkable characters are stored in @a chars[] on return.
*
* The function returns the actual number of walkable characters from @a s.
* Note that this may not equal the number of characters stored in @a chars[]
* if @a chars_nelm is less than the actual number.
*
* Available since: 0.2.6
*/
int
trie_state_walkable_chars (const TrieState *s,
AlphaChar chars[],
int chars_nelm)
{
int syms_num = 0;
if (!s->is_suffix) {
Symbols *syms = da_output_symbols (s->trie->da, s->index);
int i;
syms_num = symbols_num (syms);
for (i = 0; i < syms_num && i < chars_nelm; i++) {
TrieChar tc = symbols_get (syms, i);
chars[i] = alpha_map_trie_to_char (s->trie->alpha_map, tc);
}
symbols_free (syms);
} else {
const TrieChar *suffix = tail_get_suffix (s->trie->tail, s->index);
chars[0] = alpha_map_trie_to_char (s->trie->alpha_map,
suffix[s->suffix_idx]);
syms_num = 1;
}
return syms_num;
}
/**
* @brief Insert a branch from trie node
*
* @param d : the double-array structure
* @param s : the state to add branch to
* @param c : the character for the branch label
*
* @return the index of the new node
*
* Insert a new arc labelled with character @a c from the trie node
* represented by index @a s in double-array structure @a d.
* Note that it assumes that no such arc exists before inserting.
*/
TrieIndex
da_insert_branch (DArray *d, TrieIndex s, TrieChar c)
{
TrieIndex base, next;
base = da_get_base (d, s);
if (base > 0) {
next = base + c;
/* if already there, do not actually insert */
if (da_get_check (d, next) == s)
return next;
/* if (base + c) > TRIE_INDEX_MAX which means 'next' is overflow,
* or cell [next] is not free, relocate to a free slot
*/
if (base > TRIE_INDEX_MAX - c || !da_check_free_cell (d, next)) {
Symbols *symbols;
TrieIndex new_base;
/* relocate BASE[s] */
symbols = da_output_symbols (d, s);
symbols_add (symbols, c);
new_base = da_find_free_base (d, symbols);
symbols_free (symbols);
if (TRIE_INDEX_ERROR == new_base)
return TRIE_INDEX_ERROR;
da_relocate_base (d, s, new_base);
next = new_base + c;
}
} else {
Symbols *symbols;
TrieIndex new_base;
symbols = symbols_new ();
symbols_add (symbols, c);
new_base = da_find_free_base (d, symbols);
symbols_free (symbols);
if (TRIE_INDEX_ERROR == new_base)
return TRIE_INDEX_ERROR;
da_set_base (d, s, new_base);
next = new_base + c;
}
da_alloc_cell (d, next);
da_set_check (d, next, s);
return next;
}
static void
da_relocate_base (DArray *d,
TrieIndex s,
TrieIndex new_base)
{
TrieIndex old_base;
Symbols *symbols;
int i;
old_base = da_get_base (d, s);
symbols = da_output_symbols (d, s);
for (i = 0; i < symbols_num (symbols); i++) {
TrieIndex old_next, new_next, old_next_base;
old_next = old_base + symbols_get (symbols, i);
new_next = new_base + symbols_get (symbols, i);
old_next_base = da_get_base (d, old_next);
/* allocate new next node and copy BASE value */
da_alloc_cell (d, new_next);
da_set_check (d, new_next, s);
da_set_base (d, new_next, old_next_base);
/* old_next node is now moved to new_next
* so, all cells belonging to old_next
* must be given to new_next
*/
/* preventing the case of TAIL pointer */
if (old_next_base > 0) {
TrieIndex c, max_c;
max_c = MIN_VAL (TRIE_CHAR_MAX, TRIE_INDEX_MAX - old_next_base);
for (c = 0; c < max_c; c++) {
if (da_get_check (d, old_next_base + c) == old_next)
da_set_check (d, old_next_base + c, new_next);
}
}
/* free old_next node */
da_free_cell (d, old_next);
}
symbols_free (symbols);
/* finally, make BASE[s] point to new_base */
da_set_base (d, s, new_base);
}
