Add kmod_list_remove_n_latest()

diff --git a/libkmod/libkmod-list.c b/libkmod/libkmod-list.c
index d74d66d..d9caba0 100644 (file)
--- a/libkmod/libkmod-list.c
+++ b/libkmod/libkmod-list.c
@@ -138,6 +138,34 @@ struct kmod_list *kmod_list_remove_data(struct kmod_list *list,
        return container_of(node, struct kmod_list, node);
 }
 
+/*
+ * n must be greater to or equal the number of elements (we don't check the
+ * condition
+ */
+struct kmod_list *kmod_list_remove_n_latest(struct kmod_list *list,
+                                                       unsigned int n)
+{
+       struct kmod_list *l;
+       unsigned int i;
+
+       /*
+        * Get last element, remove all appended elments and if list became
+        * empty, set return pointer to NULL
+        */
+       l = kmod_list_prev(list, list);
+       if (l == NULL)
+               l = list;
+
+       for (i = 0; i < n; i++)
+               l = kmod_list_remove(l);
+
+       /* If list became empty, save it*/
+       if (l == NULL)
+               list = NULL;
+
+       return list;
+}
+
 KMOD_EXPORT struct kmod_list *kmod_list_prev(struct kmod_list *list,
                                                        struct kmod_list *curr)
 {

diff --git a/libkmod/libkmod-private.h b/libkmod/libkmod-private.h
index 55626f2..af1c93e 100644 (file)
--- a/libkmod/libkmod-private.h
+++ b/libkmod/libkmod-private.h
@@ -51,7 +51,8 @@ struct kmod_list *kmod_list_prepend(struct kmod_list *list, void *data) __must_c
 struct kmod_list *kmod_list_remove(struct kmod_list *list);
 struct kmod_list *kmod_list_remove_data(struct kmod_list *list,
                                        const void *data) __must_check;
-
+struct kmod_list *kmod_list_remove_n_latest(struct kmod_list *list,
+                                               unsigned int n) __must_check;
 
 /* libkmod.c */
 const char *kmod_get_dirname(struct kmod_ctx *ctx) __attribute__((nonnull(1)));