[phrases] New trie_add_nodes_only method for concatenating strings to the trie, plus boolean return values on trie_add_* APIs

src/trie.c

@@ -609,12 +609,47 @@ void trie_print(trie_t *self) {
 
 }
 
-void trie_add_at_index(trie_t *self, uint32_t node_id, char *key, uint32_t data) {
+
+uint32_t trie_add_nodes_only(trie_t *self, uint32_t node_id, char *key, size_t len) {
+    unsigned char *ptr = (unsigned char *)key; 
+    uint32_t last_node_id = node_id;
+    trie_node_t last_node = trie_get_node(self, node_id);
+    if (last_node.base == NULL_ID) return NULL_ID;
+
+    uint32_t original_node_id = node_id;
+
+    trie_node_t node;
+
+    // Walks node until prefix reached, including the trailing \0
+
+    for (int i = 0; i < len; ptr++, i++, last_node_id = node_id, last_node = node) {
+        log_debug("--- char=%c\n", *ptr);
+        node_id = trie_get_transition_index(self, last_node, *ptr);
+        log_debug("node_id=%d\n", node_id);
+        if (node_id != NULL_ID) {
+            trie_make_room_for(self, node_id);
+        }
+
+        node = trie_get_node(self, node_id);
+        log_debug("node.check=%d, last_node_id=%d, node.base=%d\n", node.check, last_node_id, node.base);
+
+        if (node.check < 0 || (node.check != last_node_id)) {
+            node_id = trie_add_transition(self, last_node_id, *ptr);
+            if (node_id == TRIE_INDEX_ERROR) {
+                trie_prune_up_to(self, original_node_id, last_node_id);
+                return NULL_ID;
+            }
+        }
+    }
+    return node_id;
+}
+
+bool trie_add_at_index(trie_t *self, uint32_t node_id, char *key, uint32_t data) {
     int num_chars = strlen(key);
     unsigned char *ptr = (unsigned char *)key; 
     uint32_t last_node_id = node_id;
     trie_node_t last_node = trie_get_node(self, node_id);
-    if (last_node.base == NULL_ID) return;
+    if (last_node.base == NULL_ID) return false;
 
     trie_node_t node;
 
@@ -634,25 +669,25 @@ void trie_add_at_index(trie_t *self, uint32_t node_id, char *key, uint32_t data)
         if (node.check < 0 || (node.check != last_node_id)) {
             log_debug("last_node_id=%d, ptr=%s, tail_pos=%zu\n", last_node_id,  ptr, self->tail->n);
             trie_separate_tail(self, last_node_id, ptr, data);
-            return;
+            return true;
         } else if (node.base < 0 && node.check == last_node_id) {
             log_debug("Case 3 insertion\n");
             trie_tail_merge(self, node_id, ptr + 1, data);
-            return;
+            return true;
         }
     }
 
-    return;
+    return true;
 }
 
 
-void trie_add(trie_t *self, char *key, uint32_t data) {
-    if (strlen(key) == 0) return;
-    trie_add_at_index(self, ROOT_ID, key, data);
+bool trie_add(trie_t *self, char *key, uint32_t data) {
+    if (strlen(key) == 0) return false;
+    return trie_add_at_index(self, ROOT_ID, key, data);
 }
 
-void trie_add_suffix(trie_t *self, char *key, uint32_t data) {
-    if (strlen(key) == 0) return;
+bool trie_add_suffix(trie_t *self, char *key, uint32_t data) {
+    if (strlen(key) == 0) return false;
     trie_node_t root = trie_get_root(self);
 
     uint32_t node_id = trie_get_transition_index(self, root, '\0');
@@ -662,8 +697,9 @@ void trie_add_suffix(trie_t *self, char *key, uint32_t data) {
     }
 
     char *suffix = utf8_reversed_string(key); 
-    trie_add_at_index(self, node_id, suffix, data);
+    bool success = trie_add_at_index(self, node_id, suffix, data);
     free(suffix);
+    return success;
 }
 
 uint32_t trie_get_from_index(trie_t *self, char *word, size_t len, uint32_t i) {
@@ -680,7 +716,7 @@ uint32_t trie_get_from_index(trie_t *self, char *word, size_t len, uint32_t i) {
     /* Include NUL-byte if we're looking for whole phrases.
     *  It may be stored if this phrase is a prefix of a longer one */
 
-    for (int i = 0; i < len; i++, ptr++, node_id = next_id) {
+    for (int i = 0; i < len + 1; i++, ptr++, node_id = next_id) {
         next_id = trie_get_transition_index(self, node, *ptr);
         node = trie_get_node(self, next_id);
 
@@ -700,7 +736,7 @@ uint32_t trie_get_from_index(trie_t *self, char *word, size_t len, uint32_t i) {
             int tail_match = strncmp((char *)current_tail, query_tail, query_tail_len);
 
             if (tail_match == 0) {
-                return next_id;
+                return data_node.data;
             } else {
                 return NULL_ID;
             }

src/trie.h

@@ -91,9 +91,10 @@ void trie_set_tail(trie_t *self, unsigned char *tail, int32_t tail_pos);
 int32_t trie_separate_tail(trie_t *self, uint32_t from_index, unsigned char *tail, uint32_t data);
 void trie_tail_merge(trie_t *self, uint32_t old_node_id, unsigned char *suffix, uint32_t data);
 
-void trie_add_at_index(trie_t *self, uint32_t node_id, char *key, uint32_t data);
-void trie_add(trie_t *self, char *key, uint32_t data);
-void trie_add_suffix(trie_t *self, char *key, uint32_t data);
+uint32_t trie_add_nodes_only(trie_t *self, uint32_t node_id, char *key, size_t len);
+bool trie_add_at_index(trie_t *self, uint32_t node_id, char *key, uint32_t data);
+bool trie_add(trie_t *self, char *key, uint32_t data);
+bool trie_add_suffix(trie_t *self, char *key, uint32_t data);
 
 uint32_t trie_get_from_index(trie_t *self, char *word, size_t len, uint32_t i);
 uint32_t trie_get_len(trie_t *self, char *word, size_t len);