chore: added some comments

tries/include/ternarytrie.h

@@ -30,6 +30,13 @@ typedef struct ttrie TernaryTrie;
  */
 TernaryTrie* ternarytrie_init();
 
+/**
+ * Populate trie with entries stored in the given file.
+ *
+ * @param trie
+ * @param file_path path to file containing entries
+ * @return amount of entries added; -1 if an error occured
+ */
 int ternarytrie_populate(TernaryTrie* trie, const char* file_path);
 
 /**
@@ -43,24 +50,26 @@ void ternarytrie_free(TernaryTrie* trie);
  * Search whether a string is contained in this trie.
  *
  * @param trie
- * @param string
- * @return true if the string is contained within this trie, false otherwise
+ * @param key
+ * @return pointer to payload string; NULL if not found
  */
-char * ternarytrie_search(TernaryTrie* trie, const char* string);
+char * ternarytrie_search(TernaryTrie* trie, const char* key);
 
 /**
  * Add a string to this trie.
  *
  * @param trie
- * @param string
+ * @param key
+ * @param payload payload to add
  * @return true if the trie was changed by this operation, false if it was already present
  */
-bool ternarytrie_add(TernaryTrie* trie, const char* string, const char *payload);
+bool ternarytrie_add(TernaryTrie* trie, const char* key, const char *payload);
 
 /**
  * Add a payload by generating a random string as the key.
  *
  * @param trie
+ * @param payload payload to add
  * @return the generated key
  */
 char *ternarytrie_add_random(TernaryTrie *trie, const char *payload);
@@ -72,10 +81,10 @@ char *ternarytrie_add_random(TernaryTrie *trie, const char *payload);
  * Removing the string from the trie should not free the string's memory.
  *
  * @param trie
- * @param string
+ * @param key
  * @return true if the string was present and has been removed, false if it was not present
  */
-bool ternarytrie_remove(TernaryTrie* trie, const char* string);
+bool ternarytrie_remove(TernaryTrie* trie, const char* key);
 
 /**
  * Returns the number of strings in this trie.