Mercurial > hg > webserver / file diff

--- a/src/ucx/cx/list.h	Sat Nov 29 19:03:52 2025 +0100
+++ b/src/ucx/cx/list.h	Sun Nov 30 18:25:55 2025 +0100
@@ -170,6 +170,12 @@
     void (*reverse)(struct cx_list_s *list);
 
     /**
+     * Optional member function for changing the capacity.
+     * If the list does not support overallocation, this can be set to @c NULL.
+     */
+    int (*change_capacity)(struct cx_list_s *list, size_t new_capacity);
+
+    /**
      * Member function for returning an iterator pointing to the specified index.
      */
     struct cx_iterator_s (*iterator)(const struct cx_list_s *list, size_t index, bool backward);
@@ -1147,6 +1153,40 @@
 cx_attr_nonnull
 CX_EXPORT int cxListUnionSimple(CxList *dst, const CxList *src, const CxList *other);
 
+/**
+ * Asks the list to reserve enough memory for a given total number of elements.
+ *
+ * List implementations are free to choose if reserving memory upfront makes
+ * sense.
+ * For example, array-based implementations usually do support reserving memory
+ * for additional elements while linked lists usually don't.
+ *
+ * @note When the requested capacity is smaller than the current size,
+ * this function returns zero without performing any action.
+ *
+ * @param list the list
+ * @param capacity the expected total number of elements
+ * @retval zero on success or when overallocation is not supported
+ * @retval non-zero when an allocation error occurred
+ * @see cxListShrink()
+ */
+cx_attr_nonnull
+CX_EXPORT int cxListReserve(CxList *list, size_t capacity);
+
+/**
+ * Advises the list to free any overallocated memory.
+ *
+ * Lists that do not support overallocation simply return zero.
+ *
+ * This function usually returns zero, except for very special and custom
+ * list and/or allocator implementations where freeing memory can fail.
+ *
+ * @param list the list
+ * @return usually zero
+ */
+cx_attr_nonnull
+CX_EXPORT int cxListShrink(CxList *list);
+
 #ifdef __cplusplus
 } // extern "C"
 #endif