1 files changed, 61 insertions, 0 deletions
diff --git a/xen/ring.c b/xen/ring.c
new file mode 100644
index 00000000..8644059e
--- /dev/null
+++ b/xen/ring.c
@@ -0,0 +1,61 @@
+/*
+ *  Copyright (C) 2006 Samuel Thibault <samuel.thibault@ens-lyon.org>
+ *
+ * This program is free software ; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation ; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with the program ; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <sys/types.h>
+#include <string.h>
+#include "ring.h"
+
+/* dest is ring */
+void hyp_ring_store(void *dest, const void *src, size_t size, void *start, void *end)
+{
+	if (dest + size > end) {
+		size_t first_size = end - dest;
+		memcpy(dest, src, first_size);
+		src += first_size;
+		dest = start;
+		size -= first_size;
+	}
+	memcpy(dest, src, size);
+}
+
+/* src is ring */
+void hyp_ring_fetch(void *dest, const void *src, size_t size, void *start, void *end)
+{
+	if (src + size > end) {
+		size_t first_size = end - src;
+		memcpy(dest, src, first_size);
+		dest += first_size;
+		src = start;
+		size -= first_size;
+	}
+	memcpy(dest, src, size);
+}
+
+size_t hyp_ring_next_word(char **c, void *start, void *end)
+{
+	size_t n = 0;
+
+	while (**c) {
+		n++;
+		if (++(*c) == end)
+			*c = start;
+	}
+	(*c)++;
+
+	return n;
+}