+static struct uci_option *
+uci_alloc_list(struct uci_section *s, const char *name)
+{
+ struct uci_package *p = s->package;
+ struct uci_context *ctx = p->ctx;
+ struct uci_option *o;
+
+ o = uci_alloc_element(ctx, option, name, 0);
+ o->type = UCI_TYPE_LIST;
+ o->section = s;
+ uci_list_init(&o->v.list);
+ uci_list_add(&s->options, &o->e.list);
+
+ return o;
+}
+
+/* Based on an efficient hash function published by D. J. Bernstein */
+static unsigned int djbhash(unsigned int hash, char *str)
+{
+ int len = strlen(str);
+ int i;
+
+ /* initial value */
+ if (hash == ~0)
+ hash = 5381;
+
+ for(i = 0; i < len; i++) {
+ hash = ((hash << 5) + hash) + str[i];
+ }
+ return (hash & 0x7FFFFFFF);
+}
+
+/* fix up an unnamed section, e.g. after adding options to it */
+__private void uci_fixup_section(struct uci_context *ctx, struct uci_section *s)
+{
+ unsigned int hash = ~0;
+ struct uci_element *e;
+ char buf[16];
+
+ if (!s || s->e.name)
+ return;
+
+ /*
+ * Generate a name for unnamed sections. This is used as reference
+ * when locating or updating the section from apps/scripts.
+ * To make multiple concurrent versions somewhat safe for updating,
+ * the name is generated from a hash of its type and name/value
+ * pairs of its option, and it is prefixed by a counter value.
+ * If the order of the unnamed sections changes for some reason,
+ * updates to them will be rejected.
+ */
+ hash = djbhash(hash, s->type);
+ uci_foreach_element(&s->options, e) {
+ struct uci_option *o;
+ hash = djbhash(hash, e->name);
+ o = uci_to_option(e);
+ switch(o->type) {
+ case UCI_TYPE_STRING:
+ hash = djbhash(hash, o->v.string);
+ break;
+ default:
+ break;
+ }
+ }
+ sprintf(buf, "cfg%02x%04x", ++s->package->n_section, hash % (1 << 16));
+ s->e.name = uci_strdup(ctx, buf);
+}
+