+
+int build_subslice(const char *slice, const char*name, char **subslice) {
+ char *ret;
+
+ assert(slice);
+ assert(name);
+ assert(subslice);
+
+ if (streq(slice, "-.slice"))
+ ret = strappend(name, ".slice");
+ else {
+ char *e;
+
+ e = endswith(slice, ".slice");
+ if (!e)
+ return -EINVAL;
+
+ ret = new(char, (e - slice) + 1 + strlen(name) + 6 + 1);
+ if (!ret)
+ return -ENOMEM;
+
+ stpcpy(stpcpy(stpcpy(mempcpy(ret, slice, e - slice), "-"), name), ".slice");
+ }
+
+ *subslice = ret;
+ return 0;
+}