Import of Empire 4.2.12

src/lib/lwp/queue.c

@@ -0,0 +1,51 @@
+/*
+ * queue.c -- queue manipulation routines.
+ * Copyright (C) 1991-3 Stephen Crane.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * author: Stephen Crane, (jsc@doc.ic.ac.uk), Department of Computing,
+ * Imperial College of Science, Technology and Medicine, 180 Queen's
+ * Gate, London SW7 2BZ, England.
+ */
+#include "lwp.h"
+#include "lwpint.h"
+#include "prototypes.h"
+
+#if defined(_EMPTH_LWP)
+
+struct lwpProc *lwpGetFirst(q)
+	struct lwpQueue *q;
+{
+	struct lwpProc *head;
+
+	if ((head = q->head) && !(q->head = head->next))
+		q->tail = 0;
+	return (head);
+}
+
+void lwpAddTail(q, p)
+	register struct lwpQueue *q;
+	register struct lwpProc *p;
+{
+	if (!q->tail)
+		q->head = p;
+	else
+		q->tail->next = p;
+	q->tail = p;
+	p->next = 0;
+}
+
+#endif