utils llist: Added sdb_llist_get().

[sysdb.git] / src / include / utils / llist.h

diff --git a/src/include/utils/llist.h b/src/include/utils/llist.h
index 4bf9d605ad74e8d46e28c262a8c92470acf6dc47..3eefae5e19b894adf457a5d195e7840a11f79757 100644 (file)
--- a/src/include/utils/llist.h
+++ b/src/include/utils/llist.h
@@ -41,6 +41,7 @@ struct sdb_llist_iter;
 typedef struct sdb_llist_iter sdb_llist_iter_t;
 
 typedef int (*sdb_llist_cmp_cb)(const sdb_object_t *, const sdb_object_t *);
+typedef int (*sdb_llist_lookup_cb)(const sdb_object_t *, const void *user_data);
 
 /*
  * sdb_llist_create, sdb_llist_destroy:
@@ -118,11 +119,18 @@ int
 sdb_llist_insert_sorted(sdb_llist_t *list,
                sdb_object_t *obj, sdb_llist_cmp_cb);
 
+/*
+ * sdb_llist_get:
+ * Returns the i-th element of the list or NULL in case of an error.
+ */
+sdb_object_t *
+sdb_llist_get(sdb_llist_t *list, size_t i);
+
 /*
  * sdb_llist_search:
- * Search for a 'key' in the given 'list'. The function will return the first
- * entry that matches the specified 'key'. For that purpose, the 'compare'
- * function is used. It should return 0 iff the two arguments compare equal.
+ * Search for a object in the given 'list'. The function will return the first
+ * entry for which the 'lookup' callback returns 0. The 'user_data' is passed
+ * on to the lookup function on each invocation.
  *
  * Returns:
  *  - a pointer to the first matching object
@@ -130,7 +138,7 @@ sdb_llist_insert_sorted(sdb_llist_t *list,
  */
 sdb_object_t *
 sdb_llist_search(sdb_llist_t *list,
-               const sdb_object_t *key, sdb_llist_cmp_cb);
+               sdb_llist_lookup_cb lookup, const void *user_data);
 
 /*
  * sdb_llist_search_by_name:
@@ -145,6 +153,20 @@ sdb_llist_search(sdb_llist_t *list,
 sdb_object_t *
 sdb_llist_search_by_name(sdb_llist_t *list, const char *key);
 
+/*
+ * sdb_llist_remove:
+ * Removes and returns the first matchin element of the list. The ref-count of
+ * the item will not be changed, that is, if the element will not be used any
+ * further, it should be de-referenced by the caller.
+ *
+ * Returns:
+ *  - a pointer to the first matching object
+ *  - NULL else
+ */
+sdb_object_t *
+sdb_llist_remove(sdb_llist_t *list,
+               sdb_llist_lookup_cb lookup, const void *user_data);
+
 /*
  * sdb_llist_shift:
  * Removes and returns the first element of the list. The ref-count of the
@@ -158,7 +180,8 @@ sdb_llist_search_by_name(sdb_llist_t *list, const char *key);
 sdb_object_t *
 sdb_llist_shift(sdb_llist_t *list);
 
-/* sdb_llist_get_iter, sdb_llist_iter_has_next, sdb_llist_iter_get_next:
+/*
+ * sdb_llist_get_iter, sdb_llist_iter_has_next, sdb_llist_iter_get_next:
  * Iterate through the list, element by element.
  *
  * sdb_llist_iter_get_next returns NULL if there is no next element.
@@ -173,6 +196,27 @@ sdb_llist_iter_has_next(sdb_llist_iter_t *iter);
 sdb_object_t *
 sdb_llist_iter_get_next(sdb_llist_iter_t *iter);
 
+/*
+ * sdb_llist_iter_remove_current:
+ * Remove the current object from the list, that is, the object which was
+ * returned by the last call to sdb_llist_iter_get_next().
+ *
+ * This operation is not safe if another iterator is in use at the same time.
+ *
+ * Returns:
+ *  - 0 on success
+ *  - a negative value else
+ */
+int
+sdb_llist_iter_remove_current(sdb_llist_iter_t *iter);
+
+/*
+ * sdb_llist_len:
+ * Return the length (number of elements) of the list.
+ */
+size_t
+sdb_llist_len(sdb_llist_t *list);
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif