1 files changed, 119 insertions, 0 deletions
diff --git a/libnormalform_and2__.c b/libnormalform_and2__.c
new file mode 100644
index 0000000..c20eb3e
--- /dev/null
+++ b/libnormalform_and2__.c
@@ -0,0 +1,119 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+#ifndef TEST
+
+
+/** 
+ * See `.inverse` in `struct libnormalform_sentence` (AND implementation)
+ */
+static LIBNORMALFORM_SENTENCE *
+and_inverse(LIBNORMALFORM_SENTENCE *this)
+{
+	/* ¬(ab) = ¬a + ¬b */
+	LIBNORMALFORM_SENTENCE *l, *r, *ret;
+	l = this->data.binary.l->inverse(this->data.binary.l);
+	if (!l)
+		return NULL;
+	r = this->data.binary.r->inverse(this->data.binary.r);
+	if (!r) {
+		libnormalform_free(l);
+		return NULL;
+	}
+	ret = libnormalform_or2__(l, r);
+        if (ret && this->atom) {
+		ret->atom = this->atom;
+                ret->atom->refcount += 1;
+	}
+        return ret;
+}
+
+
+/** 
+ * See `.equals` in `struct libnormalform_sentence` (AND implementation)
+ */
+static int
+and_equals(LIBNORMALFORM_SENTENCE *this, LIBNORMALFORM_SENTENCE *other, int *inv_out)
+{
+	LIBNORMALFORM_SENTENCE *tl, *tr;
+	LIBNORMALFORM_SENTENCE *ol, *or;
+	int inv;
+
+	if (other->type != TYPE_AND && other->type != TYPE_OR)
+		return other->type == TYPE_XOR && other->equals(other, this, inv_out);
+
+	tl = this->data.binary.l;
+	tr = this->data.binary.r;
+	ol = other->data.binary.l;
+	or = other->data.binary.r;
+
+	if (tl->hash != ol->hash || tr->hash != or->hash)
+		return 0;
+
+	if (!tl->equals(tl, ol, inv_out)) {
+		if (tl->hash == tr->hash) {
+			ol = other->data.binary.r;
+			or = other->data.binary.l;
+			if (!tl->equals(tl, ol, inv_out))
+				return 0;
+		} else {
+			return 0;
+		}
+	}
+	if (!tr->equals(tr, or, &inv))
+		return 0;
+	return inv == *inv_out && inv == (other->type == TYPE_OR);
+}
+
+
+/** 
+ * See `.evaluate` in `struct libnormalform_sentence` (AND implementation)
+ */
+static int
+and_evaluate(LIBNORMALFORM_SENTENCE *this, void *input)
+{
+	int r = this->data.binary.l->evaluate(this->data.binary.l, input);
+	return r <= 0 ? r : this->data.binary.r->evaluate(this->data.binary.r, input);
+}
+
+
+LIBNORMALFORM_SENTENCE *
+(libnormalform_and2__)(LIBNORMALFORM_SENTENCE *l, LIBNORMALFORM_SENTENCE *r)
+{
+	static const struct libnormalform_sentence prototype = {
+		PROTOTYPE_COMMON,
+		.type = TYPE_AND,
+		.inverse = &and_inverse,
+		.equals = &and_equals,
+		.evaluate = &and_evaluate
+	};
+
+	LIBNORMALFORM_SENTENCE *ret = malloc(sizeof(*ret));
+	if (!ret) {
+		libnormalform_free(l);
+		libnormalform_free(r);
+		return NULL;
+	}
+	*ret = prototype;
+	ret->hash = AND_OR_HASH(l, r);
+	if (l->hash <= r->hash) {
+		ret->data.binary.l = l;
+		ret->data.binary.r = r;
+	} else {
+		ret->data.binary.l = r;
+		ret->data.binary.r = l;
+	}
+	return ret;
+}
+
+
+#else
+
+
+CONST int
+main(void)
+{
+	return 0; /* indirectly tested */
+}
+
+
+#endif