1 files changed, 34 insertions, 0 deletions
diff --git a/test/bitbuf.test.c b/test/bitbuf.test.c
new file mode 100644
index 0000000..58d1c4d
--- /dev/null
+++ b/test/bitbuf.test.c
@@ -0,0 +1,34 @@
+/* This file is dedicated to the public domain. */
+
+{.desc = "the bit buffer implementation"};
+
+#include "../src/bitbuf.h"
+#include "../src/intdefs.h"
+
+#include <stdio.h>
+#include <string.h>
+
+static union {
+	char buf[512];
+	bitbuf_cell buf_align[512 / sizeof(bitbuf_cell)];
+} bb_buf;
+static struct bitbuf bb = {bb_buf.buf, 512, 512 * 8, 0, false, false, "test"};
+
+TEST("The possible UB in bitbuf_appendbuf shouldn't trigger horrible bugs", 0) {
+	char unalign[3] = {'X', 'X', 'X'};
+	char _buf[32 + sizeof(bitbuf_cell)];
+	char *buf = _buf;
+	if (bitbuf_align <= 1) {
+		// *shouldn't* happen
+		fputs("what's going on with the alignment???\n", stderr);
+		return false;
+	}
+	// make sure the pointer is definitely misaligned
+	while (!((usize)buf % bitbuf_align)) ++buf;
+
+	memcpy(buf, "Misaligned test buffer contents!", 32);
+	bitbuf_appendbuf(&bb, buf, 32);
+	return !memcmp(bb.buf, buf, 32);
+}
+
+// vi: sw=4 ts=4 noet tw=80 cc=80