htable: handle v. unlikely case where entries look deleted/empty.

[ccan] / ccan / htable / test / run-clash.c

diff --git a/ccan/htable/test/run-clash.c b/ccan/htable/test/run-clash.c
new file mode 100644 (file)
index 0000000..0328c35
--- /dev/null
+++ b/ccan/htable/test/run-clash.c
@@ -0,0 +1,30 @@
+#include <ccan/htable/htable.h>
+#include <ccan/htable/htable.c>
+#include <ccan/tap/tap.h>
+#include <stdbool.h>
+#include <string.h>
+
+/* Clashy hash */
+static size_t hash(const void *elem, void *unused UNNEEDED)
+{
+       return 0;
+}
+
+int main(void)
+{
+       struct htable ht;
+
+       plan_tests(254 * 253);
+       /* We try to get two elements which clash */
+       for (size_t i = 2; i < 256; i++) {
+               for (size_t j = 2; j < 256; j++) {
+                       if (i == j)
+                               continue;
+                       htable_init(&ht, hash, NULL);
+                       htable_add(&ht, hash((void *)i, NULL), (void *)i);
+                       htable_add(&ht, hash((void *)j, NULL), (void *)j);
+                       ok1(htable_check(&ht, "test"));
+               }
+       }
+       return exit_status();
+}