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-rw-r--r--test/monniaux/uzlib/src/adler32.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/test/monniaux/uzlib/src/adler32.c b/test/monniaux/uzlib/src/adler32.c
new file mode 100644
index 00000000..1f175949
--- /dev/null
+++ b/test/monniaux/uzlib/src/adler32.c
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+/*
+ * Adler-32 checksum
+ *
+ * Copyright (c) 2003 by Joergen Ibsen / Jibz
+ * All Rights Reserved
+ *
+ * http://www.ibsensoftware.com/
+ *
+ * This software is provided 'as-is', without any express
+ * or implied warranty. In no event will the authors be
+ * held liable for any damages arising from the use of
+ * this software.
+ *
+ * Permission is granted to anyone to use this software
+ * for any purpose, including commercial applications,
+ * and to alter it and redistribute it freely, subject to
+ * the following restrictions:
+ *
+ * 1. The origin of this software must not be
+ * misrepresented; you must not claim that you
+ * wrote the original software. If you use this
+ * software in a product, an acknowledgment in
+ * the product documentation would be appreciated
+ * but is not required.
+ *
+ * 2. Altered source versions must be plainly marked
+ * as such, and must not be misrepresented as
+ * being the original software.
+ *
+ * 3. This notice may not be removed or altered from
+ * any source distribution.
+ */
+
+/*
+ * Adler-32 algorithm taken from the zlib source, which is
+ * Copyright (C) 1995-1998 Jean-loup Gailly and Mark Adler
+ */
+
+#include "tinf.h"
+
+#define A32_BASE 65521
+#define A32_NMAX 5552
+
+uint32_t uzlib_adler32(const void *data, unsigned int length, uint32_t prev_sum /* 1 */)
+{
+ const unsigned char *buf = (const unsigned char *)data;
+
+ unsigned int s1 = prev_sum & 0xffff;
+ unsigned int s2 = prev_sum >> 16;
+
+ while (length > 0)
+ {
+ int k = length < A32_NMAX ? length : A32_NMAX;
+ int i;
+
+ for (i = k / 16; i; --i, buf += 16)
+ {
+ s1 += buf[0]; s2 += s1; s1 += buf[1]; s2 += s1;
+ s1 += buf[2]; s2 += s1; s1 += buf[3]; s2 += s1;
+ s1 += buf[4]; s2 += s1; s1 += buf[5]; s2 += s1;
+ s1 += buf[6]; s2 += s1; s1 += buf[7]; s2 += s1;
+
+ s1 += buf[8]; s2 += s1; s1 += buf[9]; s2 += s1;
+ s1 += buf[10]; s2 += s1; s1 += buf[11]; s2 += s1;
+ s1 += buf[12]; s2 += s1; s1 += buf[13]; s2 += s1;
+ s1 += buf[14]; s2 += s1; s1 += buf[15]; s2 += s1;
+ }
+
+ for (i = k % 16; i; --i) { s1 += *buf++; s2 += s1; }
+
+ s1 %= A32_BASE;
+ s2 %= A32_BASE;
+
+ length -= k;
+ }
+
+ return (s2 << 16) | s1;
+}