diff -r 9c1fccda16bc -r 31bf97fdbf71 test/test_list.c
--- a/test/test_list.c	Sat Oct 09 11:12:48 2021 +0200
+++ b/test/test_list.c	Sat Dec 04 17:38:23 2021 +0100
@@ -88,8 +88,8 @@
     cx_linked_list_add(&begin, &end, loc_prev, loc_next, &nodes[0]);
     CU_ASSERT_PTR_EQUAL(begin, &nodes[0])
     CU_ASSERT_PTR_EQUAL(end, &nodes[0])
-    CU_ASSERT_PTR_EQUAL(nodes[0].prev, NULL)
-    CU_ASSERT_PTR_EQUAL(nodes[0].next, NULL)
+    CU_ASSERT_PTR_NULL(nodes[0].prev)
+    CU_ASSERT_PTR_NULL(nodes[0].next)
 
     cx_linked_list_add(&begin, &end, loc_prev, loc_next, &nodes[1]);
     CU_ASSERT_PTR_EQUAL(begin, &nodes[0])
@@ -113,6 +113,23 @@
     CU_ASSERT_PTR_EQUAL(nodes[1].next, &nodes[2])
     CU_ASSERT_PTR_EQUAL(nodes[2].prev, &nodes[1])
 
+    // test with end only / prev, next
+    memset(nodes, 0, 4 * sizeof(struct node));
+    begin = NULL;
+    end = NULL;
+
+    cx_linked_list_add(NULL, &end, loc_prev, loc_next, &nodes[0]);
+    CU_ASSERT_PTR_EQUAL(end, &nodes[0])
+    cx_linked_list_add(NULL, &end,  loc_prev, loc_next, &nodes[1]);
+    CU_ASSERT_PTR_EQUAL(end, &nodes[1])
+    CU_ASSERT_PTR_EQUAL(nodes[0].next, &nodes[1])
+    CU_ASSERT_PTR_EQUAL(nodes[1].prev, &nodes[0])
+
+    cx_linked_list_add(NULL, &end,  loc_prev, loc_next, &nodes[2]);
+    CU_ASSERT_PTR_EQUAL(end, &nodes[2])
+    CU_ASSERT_PTR_EQUAL(nodes[1].next, &nodes[2])
+    CU_ASSERT_PTR_EQUAL(nodes[2].prev, &nodes[1])
+
     // test with begin, end / next
     memset(nodes, 0, 4 * sizeof(struct node));
     begin = NULL;
@@ -127,6 +144,104 @@
     CU_ASSERT_PTR_NULL(nodes[1].prev)
 }
 
+void test_linked_list_prepend(void) {
+    struct node {
+        void *prev;
+        void *next;
+    };
+
+    struct node nodes[4];
+
+    // test with begin, end / prev, next
+    memset(nodes, 0, 4 * sizeof(struct node));
+    void *begin = NULL;
+    void *end = NULL;
+
+    ptrdiff_t loc_prev = offsetof(struct node, prev);
+    ptrdiff_t loc_next = offsetof(struct node, next);
+
+    cx_linked_list_prepend(&begin, &end, loc_prev, loc_next, &nodes[0]);
+    CU_ASSERT_PTR_EQUAL(begin, &nodes[0])
+    CU_ASSERT_PTR_EQUAL(end, &nodes[0])
+    CU_ASSERT_PTR_NULL(nodes[0].prev)
+    CU_ASSERT_PTR_NULL(nodes[0].next)
+
+    cx_linked_list_prepend(&begin, &end, loc_prev, loc_next, &nodes[1]);
+    CU_ASSERT_PTR_EQUAL(begin, &nodes[1])
+    CU_ASSERT_PTR_EQUAL(end, &nodes[0])
+    CU_ASSERT_PTR_EQUAL(nodes[1].next, &nodes[0])
+    CU_ASSERT_PTR_EQUAL(nodes[0].prev, &nodes[1])
+
+    // test with begin only / prev, next
+    memset(nodes, 0, 4 * sizeof(struct node));
+    begin = NULL;
+    end = NULL;
+
+    cx_linked_list_prepend(&begin, NULL, loc_prev, loc_next, &nodes[0]);
+    CU_ASSERT_PTR_EQUAL(begin, &nodes[0])
+    cx_linked_list_prepend(&begin, NULL, loc_prev, loc_next, &nodes[1]);
+    CU_ASSERT_PTR_EQUAL(begin, &nodes[1])
+    CU_ASSERT_PTR_EQUAL(nodes[1].next, &nodes[0])
+    CU_ASSERT_PTR_EQUAL(nodes[0].prev, &nodes[1])
+
+    cx_linked_list_prepend(&begin, NULL, loc_prev, loc_next, &nodes[2]);
+    CU_ASSERT_PTR_EQUAL(begin, &nodes[2])
+    CU_ASSERT_PTR_EQUAL(nodes[2].next, &nodes[1])
+    CU_ASSERT_PTR_EQUAL(nodes[1].prev, &nodes[2])
+
+    // test with end only / prev, next
+    memset(nodes, 0, 4 * sizeof(struct node));
+    begin = NULL;
+    end = NULL;
+
+    cx_linked_list_prepend(NULL, &end, loc_prev, loc_next, &nodes[0]);
+    CU_ASSERT_PTR_EQUAL(end, &nodes[0])
+    cx_linked_list_prepend(NULL, &end, loc_prev, loc_next, &nodes[1]);
+    CU_ASSERT_PTR_EQUAL(end, &nodes[0])
+    CU_ASSERT_PTR_EQUAL(nodes[1].next, &nodes[0])
+    CU_ASSERT_PTR_EQUAL(nodes[0].prev, &nodes[1])
+
+    cx_linked_list_prepend(NULL, &end, loc_prev, loc_next, &nodes[2]);
+    CU_ASSERT_PTR_EQUAL(end, &nodes[0])
+    CU_ASSERT_PTR_EQUAL(nodes[2].next, &nodes[1])
+    CU_ASSERT_PTR_EQUAL(nodes[1].prev, &nodes[2])
+
+    // test with begin, end / next
+    memset(nodes, 0, 4 * sizeof(struct node));
+    begin = NULL;
+    end = NULL;
+
+    cx_linked_list_prepend(&begin, &end, -1, loc_next, &nodes[0]);
+    CU_ASSERT_PTR_EQUAL(begin, &nodes[0])
+    CU_ASSERT_PTR_EQUAL(end, &nodes[0])
+    cx_linked_list_prepend(&begin, &end, -1, loc_next, &nodes[1]);
+    cx_linked_list_prepend(&begin, &end, -1, loc_next, &nodes[2]);
+    CU_ASSERT_PTR_EQUAL(begin, &nodes[2])
+    CU_ASSERT_PTR_EQUAL(end, &nodes[0])
+    CU_ASSERT_PTR_EQUAL(nodes[1].next, &nodes[0])
+    CU_ASSERT_PTR_EQUAL(nodes[2].next, &nodes[1])
+    CU_ASSERT_PTR_NULL(nodes[1].prev)
+    CU_ASSERT_PTR_NULL(nodes[0].prev)
+}
+
+void test_linked_list_first(void) {
+    CU_ASSERT_PTR_NULL(cx_linked_list_first(NULL, 0))
+
+    struct node {
+        int data;
+        void *prev;
+    };
+    ptrdiff_t loc = offsetof(struct node, prev);
+
+    struct node first = {1, NULL};
+    struct node second = {2, &first};
+    struct node third = {3, &second};
+
+    CU_ASSERT_PTR_EQUAL(cx_linked_list_first(&first, loc), &first)
+    CU_ASSERT_PTR_EQUAL(cx_linked_list_first(&second, loc), &first)
+    CU_ASSERT_PTR_EQUAL(cx_linked_list_first(&third, loc), &first)
+}
+
 void test_linked_list_last(void) {
     CU_ASSERT_PTR_NULL(cx_linked_list_last(NULL, 0))
 
@@ -738,7 +853,9 @@
     suite = CU_add_suite("low level linked list", NULL, NULL);
 
     cu_add_test(suite, test_linked_list_at);
+    cu_add_test(suite, test_linked_list_prepend);
     cu_add_test(suite, test_linked_list_add);
+    cu_add_test(suite, test_linked_list_first);
     cu_add_test(suite, test_linked_list_last);
     cu_add_test(suite, test_linked_list_prev);
     cu_add_test(suite, test_linked_list_remove);