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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/u-boot/lib/zlib/adler32.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/u-boot/lib/zlib/adler32.c')
-rw-r--r--qemu/roms/u-boot/lib/zlib/adler32.c122
1 files changed, 122 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/lib/zlib/adler32.c b/qemu/roms/u-boot/lib/zlib/adler32.c
new file mode 100644
index 000000000..b468441d7
--- /dev/null
+++ b/qemu/roms/u-boot/lib/zlib/adler32.c
@@ -0,0 +1,122 @@
+/* adler32.c -- compute the Adler-32 checksum of a data stream
+ * Copyright (C) 1995-2004 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* @(#) $Id$ */
+
+#define ZLIB_INTERNAL
+#include "zlib.h"
+
+#define BASE 65521UL /* largest prime smaller than 65536 */
+#define NMAX 5552
+/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
+
+#define DO1(buf,i) {adler += (buf)[i]; sum2 += adler;}
+#define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
+#define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
+#define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
+#define DO16(buf) DO8(buf,0); DO8(buf,8);
+
+/* use NO_DIVIDE if your processor does not do division in hardware */
+#ifdef NO_DIVIDE
+# define MOD(a) \
+ do { \
+ if (a >= (BASE << 16)) a -= (BASE << 16); \
+ if (a >= (BASE << 15)) a -= (BASE << 15); \
+ if (a >= (BASE << 14)) a -= (BASE << 14); \
+ if (a >= (BASE << 13)) a -= (BASE << 13); \
+ if (a >= (BASE << 12)) a -= (BASE << 12); \
+ if (a >= (BASE << 11)) a -= (BASE << 11); \
+ if (a >= (BASE << 10)) a -= (BASE << 10); \
+ if (a >= (BASE << 9)) a -= (BASE << 9); \
+ if (a >= (BASE << 8)) a -= (BASE << 8); \
+ if (a >= (BASE << 7)) a -= (BASE << 7); \
+ if (a >= (BASE << 6)) a -= (BASE << 6); \
+ if (a >= (BASE << 5)) a -= (BASE << 5); \
+ if (a >= (BASE << 4)) a -= (BASE << 4); \
+ if (a >= (BASE << 3)) a -= (BASE << 3); \
+ if (a >= (BASE << 2)) a -= (BASE << 2); \
+ if (a >= (BASE << 1)) a -= (BASE << 1); \
+ if (a >= BASE) a -= BASE; \
+ } while (0)
+# define MOD4(a) \
+ do { \
+ if (a >= (BASE << 4)) a -= (BASE << 4); \
+ if (a >= (BASE << 3)) a -= (BASE << 3); \
+ if (a >= (BASE << 2)) a -= (BASE << 2); \
+ if (a >= (BASE << 1)) a -= (BASE << 1); \
+ if (a >= BASE) a -= BASE; \
+ } while (0)
+#else
+# define MOD(a) a %= BASE
+# define MOD4(a) a %= BASE
+#endif
+
+/* ========================================================================= */
+uLong ZEXPORT adler32(uLong adler, const Bytef *buf, uInt len)
+{
+ unsigned long sum2;
+ unsigned n;
+
+ /* split Adler-32 into component sums */
+ sum2 = (adler >> 16) & 0xffff;
+ adler &= 0xffff;
+
+ /* in case user likes doing a byte at a time, keep it fast */
+ if (len == 1) {
+ adler += buf[0];
+ if (adler >= BASE)
+ adler -= BASE;
+ sum2 += adler;
+ if (sum2 >= BASE)
+ sum2 -= BASE;
+ return adler | (sum2 << 16);
+ }
+
+ /* initial Adler-32 value (deferred check for len == 1 speed) */
+ if (buf == Z_NULL)
+ return 1L;
+
+ /* in case short lengths are provided, keep it somewhat fast */
+ if (len < 16) {
+ while (len--) {
+ adler += *buf++;
+ sum2 += adler;
+ }
+ if (adler >= BASE)
+ adler -= BASE;
+ MOD4(sum2); /* only added so many BASE's */
+ return adler | (sum2 << 16);
+ }
+
+ /* do length NMAX blocks -- requires just one modulo operation */
+ while (len >= NMAX) {
+ len -= NMAX;
+ n = NMAX / 16; /* NMAX is divisible by 16 */
+ do {
+ DO16(buf); /* 16 sums unrolled */
+ buf += 16;
+ } while (--n);
+ MOD(adler);
+ MOD(sum2);
+ }
+
+ /* do remaining bytes (less than NMAX, still just one modulo) */
+ if (len) { /* avoid modulos if none remaining */
+ while (len >= 16) {
+ len -= 16;
+ DO16(buf);
+ buf += 16;
+ }
+ while (len--) {
+ adler += *buf++;
+ sum2 += adler;
+ }
+ MOD(adler);
+ MOD(sum2);
+ }
+
+ /* return recombined sums */
+ return adler | (sum2 << 16);
+}