Bool
trie_store (Trie *trie, const TrieChar *key, TrieData data)
{
TrieIndex s, t;
short suffix_idx;
const TrieChar *p;
size_t len;
/* walk through branches */
s = da_get_root (trie->da);
for (p = key; !trie_da_is_separate (trie->da, s); p++) {
if (!da_walk (trie->da, &s, *p))
return trie_branch_in_branch (trie, s, p, data);
if ('\0' == *p)
break;
}
/* walk through tail */
t = trie_da_get_tail_index (trie->da, s);
if ('\0' != *p) {
suffix_idx = 0;
len = strlen ((const char *) p) + 1; /* including null-terminator */
if (tail_walk_str (trie->tail, t, &suffix_idx, p, len) != len)
return trie_branch_in_tail (trie, s, p, data);
}
/* duplicated key, overwrite val */
tail_set_data (trie->tail, t, data);
return TRUE;
}
Bool
trie_retrieve (Trie *trie, const TrieChar *key, TrieData *o_data)
{
TrieIndex s;
short suffix_idx;
const TrieChar *p;
size_t len;
/* walk through branches */
s = da_get_root (trie->da);
for (p = key; !trie_da_is_separate (trie->da, s); p++) {
if (!da_walk (trie->da, &s, *p))
return FALSE;
if ('\0' == *p)
break;
}
/* walk through tail */
s = trie_da_get_tail_index (trie->da, s);
if ('\0' != *p) {
suffix_idx = 0;
len = strlen ((const char *) p) + 1; /* including null-terminator */
if (tail_walk_str (trie->tail, s, &suffix_idx, p, len) != len)
return FALSE;
}
/* found, set the val and return */
if (o_data)
*o_data = tail_get_data (trie->tail, s);
return TRUE;
}
/**
* @brief Get data from terminal state
*
* @param s : a terminal state
*
* @return the data associated with the terminal state @a s,
* or TRIE_DATA_ERROR if @a s is not a terminal state
*
*/
TrieData
trie_state_get_terminal_data (const TrieState *s)
{
TrieIndex tail_index;
TrieIndex index = s->index;
if (!s)
return TRIE_DATA_ERROR;
if (!s->is_suffix){
if (!trie_da_is_separate(s->trie->da, index)) {
/* walk to a terminal char to get the data */
Bool ret = da_walk (s->trie->da, &index, TRIE_CHAR_TERM);
if (!ret) {
return TRIE_DATA_ERROR;
}
}
tail_index = trie_da_get_tail_index (s->trie->da, index);
}
else {
tail_index = s->index;
}
return tail_get_data (s->trie->tail, tail_index);
}
static Bool
trie_store_conditionally (Trie *trie,
const AlphaChar *key,
TrieData data,
Bool is_overwrite)
{
TrieIndex s, t;
short suffix_idx;
const AlphaChar *p, *sep;
/* walk through branches */
s = da_get_root (trie->da);
for (p = key; !trie_da_is_separate (trie->da, s); p++) {
if (!da_walk (trie->da, &s,
alpha_map_char_to_trie (trie->alpha_map, *p)))
{
TrieChar *key_str;
Bool res;
key_str = alpha_map_char_to_trie_str (trie->alpha_map, p);
res = trie_branch_in_branch (trie, s, key_str, data);
free (key_str);
return res;
}
if (0 == *p)
break;
}
/* walk through tail */
sep = p;
t = trie_da_get_tail_index (trie->da, s);
suffix_idx = 0;
for ( ; ; p++) {
if (!tail_walk_char (trie->tail, t, &suffix_idx,
alpha_map_char_to_trie (trie->alpha_map, *p)))
{
TrieChar *tail_str;
Bool res;
tail_str = alpha_map_char_to_trie_str (trie->alpha_map, sep);
res = trie_branch_in_tail (trie, s, tail_str, data);
free (tail_str);
return res;
}
if (0 == *p)
break;
}
/* duplicated key, overwrite val if flagged */
if (!is_overwrite) {
return FALSE;
}
tail_set_data (trie->tail, t, data);
trie->is_dirty = TRUE;
return TRUE;
}
Bool
trie_state_walk (TrieState *s, const TrieChar c)
{
if (!s->is_suffix) {
Bool ret;
ret = da_walk (s->trie->da, &s->index, c);
if (ret && trie_da_is_separate (s->trie->da, s->index)) {
s->index = trie_da_get_tail_index (s->trie->da, s->index);
s->suffix_idx = 0;
s->is_suffix = TRUE;
}
return ret;
} else {
return tail_walk_char (s->trie->tail, s->index, &s->suffix_idx, c);
}
}
/**
* @brief Get data for the entry referenced by an iterator
*
* @param iter : an iterator
*
* @return the data associated with the entry referenced by iterator @a iter,
* or TRIE_DATA_ERROR if @a iter does not reference to a unique entry
*
* Get value for the entry referenced by an iterator. Getting value from an
* un-iterated (or broken for any reason) iterator will result in
* TRIE_DATA_ERROR.
*
* Available since: 0.2.6
*/
TrieData
trie_iterator_get_data (const TrieIterator *iter)
{
const TrieState *s = iter->state;
TrieIndex tail_index;
if (!s)
return TRIE_DATA_ERROR;
if (!s->is_suffix) {
if (!trie_da_is_separate (s->trie->da, s->index))
return TRIE_DATA_ERROR;
tail_index = trie_da_get_tail_index (s->trie->da, s->index);
} else {
tail_index = s->index;
}
return tail_get_data (s->trie->tail, tail_index);
}
/**
* @brief Walk the trie from the state
*
* @param s : current state
* @param c : key character for walking
*
* @return boolean value indicating the success of the walk
*
* Walk the trie stepwise, using a given character @a c.
* On return, the state @a s is updated to the new state if successfully walked.
*/
Bool
trie_state_walk (TrieState *s, AlphaChar c)
{
TrieChar tc = alpha_map_char_to_trie (s->trie->alpha_map, c);
if (!s->is_suffix) {
Bool ret;
ret = da_walk (s->trie->da, &s->index, tc);
if (ret && trie_da_is_separate (s->trie->da, s->index)) {
s->index = trie_da_get_tail_index (s->trie->da, s->index);
s->suffix_idx = 0;
s->is_suffix = TRUE;
}
return ret;
} else {
return tail_walk_char (s->trie->tail, s->index, &s->suffix_idx, tc);
}
}
/**
* @brief Delete an entry from trie
*
* @param trie : the trie
* @param key : the key for the entry to delete
*
* @return boolean value indicating whether the key exists and is removed
*
* Delete an entry for the given @a key from @a trie.
*/
Bool
trie_delete (Trie *trie, const AlphaChar *key)
{
TrieIndex s, t;
short suffix_idx;
const AlphaChar *p;
/* walk through branches */
s = da_get_root (trie->da);
for (p = key; !trie_da_is_separate (trie->da, s); p++) {
if (!da_walk (trie->da, &s,
alpha_map_char_to_trie (trie->alpha_map, *p)))
{
return FALSE;
}
if (0 == *p)
break;
}
/* walk through tail */
t = trie_da_get_tail_index (trie->da, s);
suffix_idx = 0;
for ( ; ; p++) {
if (!tail_walk_char (trie->tail, t, &suffix_idx,
alpha_map_char_to_trie (trie->alpha_map, *p)))
{
return FALSE;
}
if (0 == *p)
break;
}
tail_delete (trie->tail, t);
da_set_base (trie->da, s, TRIE_INDEX_ERROR);
da_prune (trie->da, s);
trie->is_dirty = TRUE;
return TRUE;
}
/**
* @brief Retrieve an entry from trie
*
* @param trie : the trie
* @param key : the key for the entry to retrieve
* @param o_data : the storage for storing the entry data on return
*
* @return boolean value indicating the existence of the entry.
*
* Retrieve an entry for the given @a key from @a trie. On return,
* if @a key is found and @a o_data is not NULL, @a *o_data is set
* to the data associated to @a key.
*/
Bool
trie_retrieve (const Trie *trie, const AlphaChar *key, TrieData *o_data)
{
TrieIndex s;
short suffix_idx;
const AlphaChar *p;
/* walk through branches */
s = da_get_root (trie->da);
for (p = key; !trie_da_is_separate (trie->da, s); p++) {
if (!da_walk (trie->da, &s,
alpha_map_char_to_trie (trie->alpha_map, *p)))
{
return FALSE;
}
if (0 == *p)
break;
}
/* walk through tail */
s = trie_da_get_tail_index (trie->da, s);
suffix_idx = 0;
for ( ; ; p++) {
if (!tail_walk_char (trie->tail, s, &suffix_idx,
alpha_map_char_to_trie (trie->alpha_map, *p)))
{
return FALSE;
}
if (0 == *p)
break;
}
/* found, set the val and return */
if (o_data)
*o_data = tail_get_data (trie->tail, s);
return TRUE;
}
