1 files changed, 119 insertions, 0 deletions
diff --git a/assorted/deque2.c b/assorted/deque2.c
new file mode 100644
index 0000000..e5c4798
--- /dev/null
+++ b/assorted/deque2.c
@@ -0,0 +1,119 @@
+/*
+ *	libHX/assorted/deque2.c
+ *	Copyright Jan Engelhardt, 2002-2007
+ *
+ *	This file is part of libHX. libHX is free software; you can
+ *	redistribute it and/or modify it under the terms of the GNU Lesser
+ *	General Public License as published by the Free Software Foundation;
+ *	either version 2.1 or (at your option) any later version.
+ *
+ *	deque2.c:
+ *	Assorted DEQUE functions that are not deemed to be useful in the
+ *	(compiled) library at this time.
+ */
+#include <stdio.h>
+#include <libHX.h>
+
+EXPORT_SYMBOL struct HXdeque_node *HXdeque_rfind(struct HXdeque *dq,
+    const void *ptr)
+{
+	struct HXdeque_node *trav;
+	for (trav = dq->last; trav != NULL; trav = trav->prev)
+		if (trav->ptr == ptr)
+			return trav;
+	return NULL;
+}
+
+EXPORT_SYMBOL void *HXdeque_rget(struct HXdeque *dq, const void *ptr)
+{
+	struct HXdeque_node *trav;
+	for (trav = dq->last; trav != NULL; trav = trav->prev)
+		if (trav->ptr == ptr)
+			return trav->ptr;
+	return NULL;
+}
+
+EXPORT_SYMBOL void *HXdeque_sget(struct HXdeque *dq, const char *s)
+{
+	struct HXdeque_node *trav;
+	for (trav = dq->first; trav != NULL; trav = trav->next)
+		if (strcmp(trav->ptr, s) == 0)
+			return trav->ptr;
+	return NULL;
+}
+
+EXPORT_SYMBOL struct HXdeque_node *HXdeque_dup(struct HXdeque *dq)
+{
+	/*
+	 * Duplicate the object on top of the stack by popping it off and
+	 * adding it again, twice.
+	 */
+	if (dq->last == NULL)
+		return NULL;
+
+	/*
+	 * The mathematical axiomatic definition is that the last element is
+	 * popped off and pushed twice. We optimize by simply "looking" at the
+	 * last and push it again.
+	 */
+	return HXdeque_push(dq, dq->last->ptr);
+}
+
+EXPORT_SYMBOL struct HXdeque_node *HXdeque_rdup(struct HXdeque *dq)
+{
+	/* Same as HXdeque_dup(), but works on the bottom of the stack */
+	if (dq->first == NULL)
+		return NULL;
+	return HXdeque_unshift(dq, dq->first->ptr);
+}
+
+EXPORT_SYMBOL struct HXdeque_node *HXdeque_toprr(struct HXdeque *dq)
+{
+	/*
+	 * Rotates the topmost three items right ([bottom]...CBA[top] =>
+	 * [bottom]...ACB[top]). Also works if there are only two items in the
+	 * stack.
+	 */
+	struct HXdeque_node *p = dq->last;
+	if (p == NULL)
+		return NULL;
+	HXdeque_down(p);
+	HXdeque_down(p);
+	return p;
+}
+
+EXPORT_SYMBOL struct HXdeque_node *HXdeque_toprl(struct HXdeque *dq)
+{
+	/* Rotates the topmost three items left (...CBA => ...BAC) */
+	struct HXdeque_node *p = dq->last;
+	if (p == NULL)
+		return NULL;
+	if (p->Prev != NULL) p = p->Prev;
+	if (p->Prev != NULL) p = p->Prev;
+	HXdeque_up(p);
+	HXdeque_up(p);
+	return p;
+}
+
+EXPORT_SYMBOL struct HXdeque_node *HXdeque_botrr(struct HXdeque *dq)
+{
+	/* (CBA... => ...ACB) */
+	struct HXdeque_node *p = dq->first;
+	if (p == NULL)
+		return NULL;
+	if (p->Prev != NULL) p = p->Prev;
+	if (p->Prev != NULL) p = p->Prev;
+	HXdeque_down(p);
+	HXdeque_down(p);
+	return p;
+}
+
+EXPORT_SYMBOL struct HXdeque_node *HXdeque_botrl(struct HXdeque *dq)
+{
+	struct HXdeque_node *p = dq->first;
+	if (p == NULL)
+		return NULL;
+	HXdeque_up(p);
+	HXdeque_up(p);
+	return p;
+}