1 files changed, 60 insertions, 0 deletions
diff --git a/package/cfgfs/src/adler.h b/package/cfgfs/src/adler.h
new file mode 100644
index 000000000..a1608705f
--- /dev/null
+++ b/package/cfgfs/src/adler.h
@@ -0,0 +1,60 @@
+/* $MirOS: contrib/hosted/fwcf/adler.h,v 1.10 2007/05/07 16:15:56 tg Exp $ */
+
+/*-
+ * Copyright (c) 2006, 2007
+ *	Thorsten Glaser <tg@mirbsd.de>
+ * The adler32 algorithm is
+ * Copyright (C) 1995 Mark Adler
+ *
+ * Provided that these terms and disclaimer and all copyright notices
+ * are retained or reproduced in an accompanying document, permission
+ * is granted to deal in this work without restriction, including un-
+ * limited rights to use, publicly perform, distribute, sell, modify,
+ * merge, give away, or sublicence.
+ *
+ * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
+ * the utmost extent permitted by applicable law, neither express nor
+ * implied; without malicious intent or gross negligence. In no event
+ * may a licensor, author or contributor be held liable for indirect,
+ * direct, other damage, loss, or other issues arising in any way out
+ * of dealing in the work, even if advised of the possibility of such
+ * damage or existence of a defect, except proven that it results out
+ * of said person's immediate fault when using the work as intended.
+ *-
+ * See also:
+ *	contrib/hosted/fwcf/adler.h
+ *	src/lib/libc/hash/adh32.c
+ *	src/kern/z/adler32s.c
+ *	src/kern/z/adler32_i386.S
+ */
+
+#ifndef ADLER_H
+#define ADLER_H	"$MirOS: contrib/hosted/fwcf/adler.h,v 1.10 2007/05/07 16:15:56 tg Exp $"
+
+/*
+ * ADLER-32 implementation
+ */
+
+#define ADLER_BASE 65521 /* largest prime smaller than 65536 */
+#define ADLER_NMAX 5552	 /* largest n: 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
+
+/* declare everything needed by the adler32 routine */
+#define ADLER_DECL		unsigned s1 = 1, s2 = 0, n
+
+/* calculate the adler32 crc of the data pointed to
+   by the 'buffer' argument, size expected in 'len'
+   which is TRASHED; stores the result in s1 and s2 */
+#define ADLER_CALC(buffer)	do {					\
+		const uint8_t *adler_buf = (const uint8_t *)(buffer);	\
+		while (len) {						\
+			len -= (n = MIN(len, ADLER_NMAX));		\
+			while (n--) {					\
+				s1 += *adler_buf++;			\
+				s2 += s1;				\
+			}						\
+			s1 %= ADLER_BASE;				\
+			s2 %= ADLER_BASE;				\
+		}							\
+	} while (0)
+
+#endif