From 6c903a8dd5d913a5e968646a47e30029d37b5ccd Mon Sep 17 00:00:00 2001
From: Yann Collet <yann.collet.73@gmail.com>
Date: Sat, 28 May 2016 13:34:07 +0200
Subject: [PATCH 1/3] updated xxhash to latest "dev" version

---
 programs/.clang_complete |   3 +
 programs/fuzzer.c        |  11 +-
 programs/xxhash.c        | 621 ++++++++++++++++-----------------------
 programs/xxhash.h        |  97 ++++--
 programs/zbufftest.c     |   9 +-
 5 files changed, 341 insertions(+), 400 deletions(-)
 create mode 100644 programs/.clang_complete

diff --git a/programs/.clang_complete b/programs/.clang_complete
new file mode 100644
index 00000000..658aa00b
--- /dev/null
+++ b/programs/.clang_complete
@@ -0,0 +1,3 @@
+-I../lib/common
+-I../lib/legacy
+-I./legacy
diff --git a/programs/fuzzer.c b/programs/fuzzer.c
index e664bf43..4b5697c4 100644
--- a/programs/fuzzer.c
+++ b/programs/fuzzer.c
@@ -42,8 +42,9 @@
 #include <time.h>        /* clock_t */
 #include "zstd_static.h" /* ZSTD_VERSION_STRING */
 #include "datagen.h"     /* RDG_genBuffer */
-#include "xxhash.h"      /* XXH64 */
 #include "mem.h"
+#define XXH_STATIC_LINKING_ONLY
+#include "xxhash.h"      /* XXH64 */
 
 
 /*-************************************
@@ -463,7 +464,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, U32 const maxD
         size_t sampleSize, sampleStart, maxTestSize, totalTestSize;
         size_t cSize, dSize, totalCSize, totalGenSize;
         U32 sampleSizeLog, nbChunks, n;
-        XXH64_CREATESTATE_STATIC(xxh64);
+        XXH64_state_t xxhState;
         U64 crcOrig;
         BYTE* sampleBuffer;
         const BYTE* dict;
@@ -614,7 +615,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, U32 const maxD
             { size_t const errorCode = ZSTD_copyCCtx(ctx, refCtx);
               CHECK (ZSTD_isError(errorCode), "ZSTD_copyCCtx error : %s", ZSTD_getErrorName(errorCode)); }
         }
-        XXH64_reset(xxh64, 0);
+        XXH64_reset(&xxhState, 0);
         nbChunks = (FUZ_rand(&lseed) & 127) + 2;
         for (totalTestSize=0, cSize=0, n=0 ; n<nbChunks ; n++) {
             sampleSizeLog = FUZ_rand(&lseed) % maxSampleLog;
@@ -629,7 +630,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, U32 const maxD
                 CHECK (ZSTD_isError(compressResult), "multi-segments compression error : %s", ZSTD_getErrorName(compressResult));
                 cSize += compressResult;
             }
-            XXH64_update(xxh64, srcBuffer+sampleStart, sampleSize);
+            XXH64_update(&xxhState, srcBuffer+sampleStart, sampleSize);
             memcpy(mirrorBuffer + totalTestSize, srcBuffer+sampleStart, sampleSize);
             totalTestSize += sampleSize;
         }
@@ -637,7 +638,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, U32 const maxD
             CHECK (ZSTD_isError(flushResult), "multi-segments epilogue error : %s", ZSTD_getErrorName(flushResult));
             cSize += flushResult;
         }
-        crcOrig = XXH64_digest(xxh64);
+        crcOrig = XXH64_digest(&xxhState);
 
         /* streaming decompression test */
         { size_t const errorCode = ZSTD_decompressBegin_usingDict(dctx, dict, dictSize);
diff --git a/programs/xxhash.c b/programs/xxhash.c
index 92df9029..e175ae96 100644
--- a/programs/xxhash.c
+++ b/programs/xxhash.c
@@ -1,41 +1,42 @@
 /*
-xxHash - Fast Hash algorithm
-Copyright (C) 2012-2016, Yann Collet
-
-BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are
-met:
-
-* Redistributions of source code must retain the above copyright
-notice, this list of conditions and the following disclaimer.
-* Redistributions in binary form must reproduce the above
-copyright notice, this list of conditions and the following disclaimer
-in the documentation and/or other materials provided with the
-distribution.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-You can contact the author at :
-- xxHash source repository : https://github.com/Cyan4973/xxHash
+*  xxHash - Fast Hash algorithm
+*  Copyright (C) 2012-2016, Yann Collet
+*
+*  BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+*
+*  Redistribution and use in source and binary forms, with or without
+*  modification, are permitted provided that the following conditions are
+*  met:
+*
+*  * Redistributions of source code must retain the above copyright
+*  notice, this list of conditions and the following disclaimer.
+*  * Redistributions in binary form must reproduce the above
+*  copyright notice, this list of conditions and the following disclaimer
+*  in the documentation and/or other materials provided with the
+*  distribution.
+*
+*  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+*  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+*  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+*  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+*  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+*  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+*  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+*  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+*  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+*  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+*  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*
+*  You can contact the author at :
+*  - xxHash homepage: http://www.xxhash.com
+*  - xxHash source repository : https://github.com/Cyan4973/xxHash
 */
 
 
 /* *************************************
 *  Tuning parameters
 ***************************************/
-/*!XXH_FORCE_MEMORY_ACCESS
+/*!XXH_FORCE_MEMORY_ACCESS :
  * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable.
  * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal.
  * The below switch allow to select different access method for improved performance.
@@ -65,24 +66,47 @@ You can contact the author at :
 /* #define XXH_ACCEPT_NULL_INPUT_POINTER 1 */
 
 /*!XXH_FORCE_NATIVE_FORMAT :
- * By default, xxHash library provides endian-independent Hash values, based on little-endian convention.
+ * By default, xxHash library provides endian-independant Hash values, based on little-endian convention.
  * Results are therefore identical for little-endian and big-endian CPU.
  * This comes at a performance cost for big-endian CPU, since some swapping is required to emulate little-endian format.
  * Should endian-independance be of no importance for your application, you may set the #define below to 1,
  * to improve speed for Big-endian CPU.
  * This option has no impact on Little_Endian CPU.
  */
-#define XXH_FORCE_NATIVE_FORMAT 0
-
-/*!XXH_USELESS_ALIGN_BRANCH :
- * This is a minor performance trick, only useful with lots of very small keys.
- * It means : don't check for aligned/unaligned input, because performance will be the same.
- * It saves one initial branch per hash.
- */
-#if defined(__i386) || defined(_M_IX86) || defined(__x86_64__) || defined(_M_X64)
-#  define XXH_USELESS_ALIGN_BRANCH 1
+#ifndef XXH_FORCE_NATIVE_FORMAT   /* can be defined externally */
+#  define XXH_FORCE_NATIVE_FORMAT 0
 #endif
 
+/*!XXH_FORCE_ALIGN_CHECK :
+ * This is a minor performance trick, only useful with lots of very small keys.
+ * It means : check for aligned/unaligned input.
+ * The check costs one initial branch per hash; set to 0 when the input data
+ * is guaranteed to be aligned.
+ */
+#ifndef XXH_FORCE_ALIGN_CHECK /* can be defined externally */
+#  if defined(__i386) || defined(_M_IX86) || defined(__x86_64__) || defined(_M_X64)
+#    define XXH_FORCE_ALIGN_CHECK 0
+#  else
+#    define XXH_FORCE_ALIGN_CHECK 1
+#  endif
+#endif
+
+
+/* *************************************
+*  Includes & Memory related functions
+***************************************/
+/* Modify the local functions below should you wish to use some other memory routines */
+/* for malloc(), free() */
+#include <stdlib.h>
+static void* XXH_malloc(size_t s) { return malloc(s); }
+static void  XXH_free  (void* p)  { free(p); }
+/* for memcpy() */
+#include <string.h>
+static void* XXH_memcpy(void* dest, const void* src, size_t size) { return memcpy(dest,src,size); }
+
+#define XXH_STATIC_LINKING_ONLY
+#include "xxhash.h"
+
 
 /* *************************************
 *  Compiler Specific Options
@@ -103,27 +127,12 @@ You can contact the author at :
 #endif
 
 
-/* *************************************
-*  Includes & Memory related functions
-***************************************/
-/* Modify the local functions below should you wish to use some other memory routines */
-/* for malloc(), free() */
-#include <stdlib.h>
-static void* XXH_malloc(size_t s) { return malloc(s); }
-static void  XXH_free  (void* p)  { free(p); }
-/* for memcpy() */
-#include <string.h>
-static void* XXH_memcpy(void* dest, const void* src, size_t size) { return memcpy(dest,src,size); }
-
-#include "xxhash.h"
-
-
 /* *************************************
 *  Basic Types
 ***************************************/
 #ifndef MEM_MODULE
 # define MEM_MODULE
-# if !defined (__VMS) && ( defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L   /* C99 */ )
+# if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L   /* C99 */
 #   include <stdint.h>
     typedef uint8_t  BYTE;
     typedef uint16_t U16;
@@ -250,6 +259,11 @@ FORCE_INLINE U32 XXH_readLE32(const void* ptr, XXH_endianess endian)
     return XXH_readLE32_align(ptr, endian, XXH_unaligned);
 }
 
+static U32 XXH_readBE32(const void* ptr)
+{
+    return XXH_CPU_LITTLE_ENDIAN ? XXH_swap32(XXH_read32(ptr)) : XXH_read32(ptr);
+}
+
 FORCE_INLINE U64 XXH_readLE64_align(const void* ptr, XXH_endianess endian, XXH_alignment align)
 {
     if (align==XXH_unaligned)
@@ -263,6 +277,11 @@ FORCE_INLINE U64 XXH_readLE64(const void* ptr, XXH_endianess endian)
     return XXH_readLE64_align(ptr, endian, XXH_unaligned);
 }
 
+static U64 XXH_readBE64(const void* ptr)
+{
+    return XXH_CPU_LITTLE_ENDIAN ? XXH_swap64(XXH_read64(ptr)) : XXH_read64(ptr);
+}
+
 
 /* *************************************
 *  Macros
@@ -273,17 +292,17 @@ FORCE_INLINE U64 XXH_readLE64(const void* ptr, XXH_endianess endian)
 /* *************************************
 *  Constants
 ***************************************/
-#define PRIME32_1   2654435761U
-#define PRIME32_2   2246822519U
-#define PRIME32_3   3266489917U
-#define PRIME32_4    668265263U
-#define PRIME32_5    374761393U
+static const U32 PRIME32_1 = 2654435761U;
+static const U32 PRIME32_2 = 2246822519U;
+static const U32 PRIME32_3 = 3266489917U;
+static const U32 PRIME32_4 =  668265263U;
+static const U32 PRIME32_5 =  374761393U;
 
-#define PRIME64_1 11400714785074694791ULL
-#define PRIME64_2 14029467366897019727ULL
-#define PRIME64_3  1609587929392839161ULL
-#define PRIME64_4  9650029242287828579ULL
-#define PRIME64_5  2870177450012600261ULL
+static const U64 PRIME64_1 = 11400714785074694791ULL;
+static const U64 PRIME64_2 = 14029467366897019727ULL;
+static const U64 PRIME64_3 =  1609587929392839161ULL;
+static const U64 PRIME64_4 =  9650029242287828579ULL;
+static const U64 PRIME64_5 =  2870177450012600261ULL;
 
 XXH_PUBLIC_API unsigned XXH_versionNumber (void) { return XXH_VERSION_NUMBER; }
 
@@ -291,6 +310,15 @@ XXH_PUBLIC_API unsigned XXH_versionNumber (void) { return XXH_VERSION_NUMBER; }
 /* ***************************
 *  Simple Hash Functions
 *****************************/
+
+static U32 XXH32_round(U32 seed, U32 input)
+{
+    seed += input * PRIME32_2;
+    seed  = XXH_rotl32(seed, 13);
+    seed *= PRIME32_1;
+    return seed;
+}
+
 FORCE_INLINE U32 XXH32_endian_align(const void* input, size_t len, U32 seed, XXH_endianess endian, XXH_alignment align)
 {
     const BYTE* p = (const BYTE*)input;
@@ -299,60 +327,40 @@ FORCE_INLINE U32 XXH32_endian_align(const void* input, size_t len, U32 seed, XXH
 #define XXH_get32bits(p) XXH_readLE32_align(p, endian, align)
 
 #ifdef XXH_ACCEPT_NULL_INPUT_POINTER
-    if (p==NULL)
-    {
+    if (p==NULL) {
         len=0;
         bEnd=p=(const BYTE*)(size_t)16;
     }
 #endif
 
-    if (len>=16)
-    {
+    if (len>=16) {
         const BYTE* const limit = bEnd - 16;
         U32 v1 = seed + PRIME32_1 + PRIME32_2;
         U32 v2 = seed + PRIME32_2;
         U32 v3 = seed + 0;
         U32 v4 = seed - PRIME32_1;
 
-        do
-        {
-            v1 += XXH_get32bits(p) * PRIME32_2;
-            v1 = XXH_rotl32(v1, 13);
-            v1 *= PRIME32_1;
-            p+=4;
-            v2 += XXH_get32bits(p) * PRIME32_2;
-            v2 = XXH_rotl32(v2, 13);
-            v2 *= PRIME32_1;
-            p+=4;
-            v3 += XXH_get32bits(p) * PRIME32_2;
-            v3 = XXH_rotl32(v3, 13);
-            v3 *= PRIME32_1;
-            p+=4;
-            v4 += XXH_get32bits(p) * PRIME32_2;
-            v4 = XXH_rotl32(v4, 13);
-            v4 *= PRIME32_1;
-            p+=4;
-        }
-        while (p<=limit);
+        do {
+            v1 = XXH32_round(v1, XXH_get32bits(p)); p+=4;
+            v2 = XXH32_round(v2, XXH_get32bits(p)); p+=4;
+            v3 = XXH32_round(v3, XXH_get32bits(p)); p+=4;
+            v4 = XXH32_round(v4, XXH_get32bits(p)); p+=4;
+        } while (p<=limit);
 
         h32 = XXH_rotl32(v1, 1) + XXH_rotl32(v2, 7) + XXH_rotl32(v3, 12) + XXH_rotl32(v4, 18);
-    }
-    else
-    {
+    } else {
         h32  = seed + PRIME32_5;
     }
 
     h32 += (U32) len;
 
-    while (p+4<=bEnd)
-    {
+    while (p+4<=bEnd) {
         h32 += XXH_get32bits(p) * PRIME32_3;
         h32  = XXH_rotl32(h32, 17) * PRIME32_4 ;
         p+=4;
     }
 
-    while (p<bEnd)
-    {
+    while (p<bEnd) {
         h32 += (*p) * PRIME32_5;
         h32 = XXH_rotl32(h32, 11) * PRIME32_1 ;
         p++;
@@ -372,22 +380,20 @@ XXH_PUBLIC_API unsigned int XXH32 (const void* input, size_t len, unsigned int s
 {
 #if 0
     /* Simple version, good for code maintenance, but unfortunately slow for small inputs */
-    XXH32_state_t state;
-    XXH32_reset(&state, seed);
-    XXH32_update(&state, input, len);
-    return XXH32_digest(&state);
+    XXH32_CREATESTATE_STATIC(state);
+    XXH32_reset(state, seed);
+    XXH32_update(state, input, len);
+    return XXH32_digest(state);
 #else
     XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
 
-#  if !defined(XXH_USELESS_ALIGN_BRANCH)
-    if ((((size_t)input) & 3) == 0)   /* Input is 4-bytes aligned, leverage the speed benefit */
-    {
-        if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-            return XXH32_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned);
-        else
-            return XXH32_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned);
-    }
-#  endif
+    if (XXH_FORCE_ALIGN_CHECK) {
+        if ((((size_t)input) & 3) == 0) {   /* Input is 4-bytes aligned, leverage the speed benefit */
+            if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
+                return XXH32_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned);
+            else
+                return XXH32_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned);
+    }   }
 
     if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
         return XXH32_endian_align(input, len, seed, XXH_littleEndian, XXH_unaligned);
@@ -396,103 +402,77 @@ XXH_PUBLIC_API unsigned int XXH32 (const void* input, size_t len, unsigned int s
 #endif
 }
 
+
+static U64 XXH64_round(U64 acc, U64 input)
+{
+    acc += input * PRIME64_2;
+    acc  = XXH_rotl64(acc, 31);
+    acc *= PRIME64_1;
+    return acc;
+}
+
+static U64 XXH64_mergeRound(U64 acc, U64 val)
+{
+    val  = XXH64_round(0, val);
+    acc ^= val;
+    acc  = acc * PRIME64_1 + PRIME64_4;
+    return acc;
+}
+
 FORCE_INLINE U64 XXH64_endian_align(const void* input, size_t len, U64 seed, XXH_endianess endian, XXH_alignment align)
 {
     const BYTE* p = (const BYTE*)input;
-    const BYTE* bEnd = p + len;
+    const BYTE* const bEnd = p + len;
     U64 h64;
 #define XXH_get64bits(p) XXH_readLE64_align(p, endian, align)
 
 #ifdef XXH_ACCEPT_NULL_INPUT_POINTER
-    if (p==NULL)
-    {
+    if (p==NULL) {
         len=0;
         bEnd=p=(const BYTE*)(size_t)32;
     }
 #endif
 
-    if (len>=32)
-    {
+    if (len>=32) {
         const BYTE* const limit = bEnd - 32;
         U64 v1 = seed + PRIME64_1 + PRIME64_2;
         U64 v2 = seed + PRIME64_2;
         U64 v3 = seed + 0;
         U64 v4 = seed - PRIME64_1;
 
-        do
-        {
-            v1 += XXH_get64bits(p) * PRIME64_2;
-            p+=8;
-            v1 = XXH_rotl64(v1, 31);
-            v1 *= PRIME64_1;
-            v2 += XXH_get64bits(p) * PRIME64_2;
-            p+=8;
-            v2 = XXH_rotl64(v2, 31);
-            v2 *= PRIME64_1;
-            v3 += XXH_get64bits(p) * PRIME64_2;
-            p+=8;
-            v3 = XXH_rotl64(v3, 31);
-            v3 *= PRIME64_1;
-            v4 += XXH_get64bits(p) * PRIME64_2;
-            p+=8;
-            v4 = XXH_rotl64(v4, 31);
-            v4 *= PRIME64_1;
-        }
-        while (p<=limit);
+        do {
+            v1 = XXH64_round(v1, XXH_get64bits(p)); p+=8;
+            v2 = XXH64_round(v2, XXH_get64bits(p)); p+=8;
+            v3 = XXH64_round(v3, XXH_get64bits(p)); p+=8;
+            v4 = XXH64_round(v4, XXH_get64bits(p)); p+=8;
+        } while (p<=limit);
 
         h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18);
+        h64 = XXH64_mergeRound(h64, v1);
+        h64 = XXH64_mergeRound(h64, v2);
+        h64 = XXH64_mergeRound(h64, v3);
+        h64 = XXH64_mergeRound(h64, v4);
 
-        v1 *= PRIME64_2;
-        v1 = XXH_rotl64(v1, 31);
-        v1 *= PRIME64_1;
-        h64 ^= v1;
-        h64 = h64 * PRIME64_1 + PRIME64_4;
-
-        v2 *= PRIME64_2;
-        v2 = XXH_rotl64(v2, 31);
-        v2 *= PRIME64_1;
-        h64 ^= v2;
-        h64 = h64 * PRIME64_1 + PRIME64_4;
-
-        v3 *= PRIME64_2;
-        v3 = XXH_rotl64(v3, 31);
-        v3 *= PRIME64_1;
-        h64 ^= v3;
-        h64 = h64 * PRIME64_1 + PRIME64_4;
-
-        v4 *= PRIME64_2;
-        v4 = XXH_rotl64(v4, 31);
-        v4 *= PRIME64_1;
-        h64 ^= v4;
-        h64 = h64 * PRIME64_1 + PRIME64_4;
-    }
-    else
-    {
+    } else {
         h64  = seed + PRIME64_5;
     }
 
     h64 += (U64) len;
 
-    while (p+8<=bEnd)
-    {
-        U64 k1 = XXH_get64bits(p);
-        k1 *= PRIME64_2;
-        k1 = XXH_rotl64(k1,31);
-        k1 *= PRIME64_1;
+    while (p+8<=bEnd) {
+        U64 const k1 = XXH64_round(0, XXH_get64bits(p));
         h64 ^= k1;
-        h64 = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4;
+        h64  = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4;
         p+=8;
     }
 
-    if (p+4<=bEnd)
-    {
+    if (p+4<=bEnd) {
         h64 ^= (U64)(XXH_get32bits(p)) * PRIME64_1;
         h64 = XXH_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
         p+=4;
     }
 
-    while (p<bEnd)
-    {
+    while (p<bEnd) {
         h64 ^= (*p) * PRIME64_5;
         h64 = XXH_rotl64(h64, 11) * PRIME64_1;
         p++;
@@ -512,22 +492,20 @@ XXH_PUBLIC_API unsigned long long XXH64 (const void* input, size_t len, unsigned
 {
 #if 0
     /* Simple version, good for code maintenance, but unfortunately slow for small inputs */
-    XXH64_state_t state;
-    XXH64_reset(&state, seed);
-    XXH64_update(&state, input, len);
-    return XXH64_digest(&state);
+    XXH64_CREATESTATE_STATIC(state);
+    XXH64_reset(state, seed);
+    XXH64_update(state, input, len);
+    return XXH64_digest(state);
 #else
     XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
 
-#  if !defined(XXH_USELESS_ALIGN_BRANCH)
-    if ((((size_t)input) & 7)==0)   /* Input is aligned, let's leverage the speed advantage */
-    {
-        if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-            return XXH64_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned);
-        else
-            return XXH64_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned);
-    }
-#  endif
+    if (XXH_FORCE_ALIGN_CHECK) {
+        if ((((size_t)input) & 7)==0) {  /* Input is aligned, let's leverage the speed advantage */
+            if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
+                return XXH64_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned);
+            else
+                return XXH64_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned);
+    }   }
 
     if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
         return XXH64_endian_align(input, len, seed, XXH_littleEndian, XXH_unaligned);
@@ -536,39 +514,13 @@ XXH_PUBLIC_API unsigned long long XXH64 (const void* input, size_t len, unsigned
 #endif
 }
 
+
 /* **************************************************
 *  Advanced Hash Functions
 ****************************************************/
 
-/*** Allocation ***/
-struct XXH32_state_s
-{
-    U64 total_len;
-    U32 seed;
-    U32 v1;
-    U32 v2;
-    U32 v3;
-    U32 v4;
-    U32 mem32[4];   /* defined as U32 for alignment */
-    U32 memsize;
-};   /* typedef'd to XXH32_state_t within xxhash.h */
-
-struct XXH64_state_s
-{
-    U64 total_len;
-    U64 seed;
-    U64 v1;
-    U64 v2;
-    U64 v3;
-    U64 v4;
-    U64 mem64[4];   /* defined as U64 for alignment */
-    U32 memsize;
-};   /* typedef'd to XXH64_state_t within xxhash.h */
-
-
 XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void)
 {
-    XXH_STATIC_ASSERT(sizeof(XXH32_stateBody_t) >= sizeof(XXH32_state_t));   /* A compilation error here means XXH32_state_t is not large enough */
     return (XXH32_state_t*)XXH_malloc(sizeof(XXH32_state_t));
 }
 XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr)
@@ -579,7 +531,6 @@ XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr)
 
 XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void)
 {
-    XXH_STATIC_ASSERT(sizeof(XXH64_stateBody_t) >= sizeof(XXH64_state_t));   /* A compilation error here means XXH64_state_t is not large enough */
     return (XXH64_state_t*)XXH_malloc(sizeof(XXH64_state_t));
 }
 XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr)
@@ -630,67 +581,37 @@ FORCE_INLINE XXH_errorcode XXH32_update_endian (XXH32_state_t* state, const void
 
     state->total_len += len;
 
-    if (state->memsize + len < 16)   /* fill in tmp buffer */
-    {
+    if (state->memsize + len < 16)  {   /* fill in tmp buffer */
         XXH_memcpy((BYTE*)(state->mem32) + state->memsize, input, len);
         state->memsize += (U32)len;
         return XXH_OK;
     }
 
-    if (state->memsize)   /* some data left from previous update */
-    {
+    if (state->memsize) {   /* some data left from previous update */
         XXH_memcpy((BYTE*)(state->mem32) + state->memsize, input, 16-state->memsize);
-        {
-            const U32* p32 = state->mem32;
-            state->v1 += XXH_readLE32(p32, endian) * PRIME32_2;
-            state->v1 = XXH_rotl32(state->v1, 13);
-            state->v1 *= PRIME32_1;
-            p32++;
-            state->v2 += XXH_readLE32(p32, endian) * PRIME32_2;
-            state->v2 = XXH_rotl32(state->v2, 13);
-            state->v2 *= PRIME32_1;
-            p32++;
-            state->v3 += XXH_readLE32(p32, endian) * PRIME32_2;
-            state->v3 = XXH_rotl32(state->v3, 13);
-            state->v3 *= PRIME32_1;
-            p32++;
-            state->v4 += XXH_readLE32(p32, endian) * PRIME32_2;
-            state->v4 = XXH_rotl32(state->v4, 13);
-            state->v4 *= PRIME32_1;
-            p32++;
+        {   const U32* p32 = state->mem32;
+            state->v1 = XXH32_round(state->v1, XXH_readLE32(p32, endian)); p32++;
+            state->v2 = XXH32_round(state->v2, XXH_readLE32(p32, endian)); p32++;
+            state->v3 = XXH32_round(state->v3, XXH_readLE32(p32, endian)); p32++;
+            state->v4 = XXH32_round(state->v4, XXH_readLE32(p32, endian)); p32++;
         }
         p += 16-state->memsize;
         state->memsize = 0;
     }
 
-    if (p <= bEnd-16)
-    {
+    if (p <= bEnd-16) {
         const BYTE* const limit = bEnd - 16;
         U32 v1 = state->v1;
         U32 v2 = state->v2;
         U32 v3 = state->v3;
         U32 v4 = state->v4;
 
-        do
-        {
-            v1 += XXH_readLE32(p, endian) * PRIME32_2;
-            v1 = XXH_rotl32(v1, 13);
-            v1 *= PRIME32_1;
-            p+=4;
-            v2 += XXH_readLE32(p, endian) * PRIME32_2;
-            v2 = XXH_rotl32(v2, 13);
-            v2 *= PRIME32_1;
-            p+=4;
-            v3 += XXH_readLE32(p, endian) * PRIME32_2;
-            v3 = XXH_rotl32(v3, 13);
-            v3 *= PRIME32_1;
-            p+=4;
-            v4 += XXH_readLE32(p, endian) * PRIME32_2;
-            v4 = XXH_rotl32(v4, 13);
-            v4 *= PRIME32_1;
-            p+=4;
-        }
-        while (p<=limit);
+        do {
+            v1 = XXH32_round(v1, XXH_readLE32(p, endian)); p+=4;
+            v2 = XXH32_round(v2, XXH_readLE32(p, endian)); p+=4;
+            v3 = XXH32_round(v3, XXH_readLE32(p, endian)); p+=4;
+            v4 = XXH32_round(v4, XXH_readLE32(p, endian)); p+=4;
+        } while (p<=limit);
 
         state->v1 = v1;
         state->v2 = v2;
@@ -698,8 +619,7 @@ FORCE_INLINE XXH_errorcode XXH32_update_endian (XXH32_state_t* state, const void
         state->v4 = v4;
     }
 
-    if (p < bEnd)
-    {
+    if (p < bEnd) {
         XXH_memcpy(state->mem32, p, bEnd-p);
         state->memsize = (int)(bEnd-p);
     }
@@ -722,31 +642,26 @@ XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* state_in, const void*
 FORCE_INLINE U32 XXH32_digest_endian (const XXH32_state_t* state, XXH_endianess endian)
 {
     const BYTE * p = (const BYTE*)state->mem32;
-    const BYTE* bEnd = (const BYTE*)(state->mem32) + state->memsize;
+    const BYTE* const bEnd = (const BYTE*)(state->mem32) + state->memsize;
     U32 h32;
 
-    if (state->total_len >= 16)
-    {
+    if (state->total_len >= 16) {
         h32 = XXH_rotl32(state->v1, 1) + XXH_rotl32(state->v2, 7) + XXH_rotl32(state->v3, 12) + XXH_rotl32(state->v4, 18);
-    }
-    else
-    {
-        h32  = state->seed + PRIME32_5;
+    } else {
+        h32 = state->seed + PRIME32_5;
     }
 
     h32 += (U32) state->total_len;
 
-    while (p+4<=bEnd)
-    {
+    while (p+4<=bEnd) {
         h32 += XXH_readLE32(p, endian) * PRIME32_3;
         h32  = XXH_rotl32(h32, 17) * PRIME32_4;
         p+=4;
     }
 
-    while (p<bEnd)
-    {
+    while (p<bEnd) {
         h32 += (*p) * PRIME32_5;
-        h32 = XXH_rotl32(h32, 11) * PRIME32_1;
+        h32  = XXH_rotl32(h32, 11) * PRIME32_1;
         p++;
     }
 
@@ -771,6 +686,9 @@ XXH_PUBLIC_API unsigned int XXH32_digest (const XXH32_state_t* state_in)
 }
 
 
+
+/* **** XXH64 **** */
+
 FORCE_INLINE XXH_errorcode XXH64_update_endian (XXH64_state_t* state, const void* input, size_t len, XXH_endianess endian)
 {
     const BYTE* p = (const BYTE*)input;
@@ -782,67 +700,35 @@ FORCE_INLINE XXH_errorcode XXH64_update_endian (XXH64_state_t* state, const void
 
     state->total_len += len;
 
-    if (state->memsize + len < 32)   /* fill in tmp buffer */
-    {
+    if (state->memsize + len < 32) {  /* fill in tmp buffer */
         XXH_memcpy(((BYTE*)state->mem64) + state->memsize, input, len);
         state->memsize += (U32)len;
         return XXH_OK;
     }
 
-    if (state->memsize)   /* some data left from previous update */
-    {
+    if (state->memsize) {   /* tmp buffer is full */
         XXH_memcpy(((BYTE*)state->mem64) + state->memsize, input, 32-state->memsize);
-        {
-            const U64* p64 = state->mem64;
-            state->v1 += XXH_readLE64(p64, endian) * PRIME64_2;
-            state->v1 = XXH_rotl64(state->v1, 31);
-            state->v1 *= PRIME64_1;
-            p64++;
-            state->v2 += XXH_readLE64(p64, endian) * PRIME64_2;
-            state->v2 = XXH_rotl64(state->v2, 31);
-            state->v2 *= PRIME64_1;
-            p64++;
-            state->v3 += XXH_readLE64(p64, endian) * PRIME64_2;
-            state->v3 = XXH_rotl64(state->v3, 31);
-            state->v3 *= PRIME64_1;
-            p64++;
-            state->v4 += XXH_readLE64(p64, endian) * PRIME64_2;
-            state->v4 = XXH_rotl64(state->v4, 31);
-            state->v4 *= PRIME64_1;
-            p64++;
-        }
+        state->v1 = XXH64_round(state->v1, XXH_readLE64(state->mem64+0, endian));
+        state->v2 = XXH64_round(state->v2, XXH_readLE64(state->mem64+1, endian));
+        state->v3 = XXH64_round(state->v3, XXH_readLE64(state->mem64+2, endian));
+        state->v4 = XXH64_round(state->v4, XXH_readLE64(state->mem64+3, endian));
         p += 32-state->memsize;
         state->memsize = 0;
     }
 
-    if (p+32 <= bEnd)
-    {
+    if (p+32 <= bEnd) {
         const BYTE* const limit = bEnd - 32;
         U64 v1 = state->v1;
         U64 v2 = state->v2;
         U64 v3 = state->v3;
         U64 v4 = state->v4;
 
-        do
-        {
-            v1 += XXH_readLE64(p, endian) * PRIME64_2;
-            v1 = XXH_rotl64(v1, 31);
-            v1 *= PRIME64_1;
-            p+=8;
-            v2 += XXH_readLE64(p, endian) * PRIME64_2;
-            v2 = XXH_rotl64(v2, 31);
-            v2 *= PRIME64_1;
-            p+=8;
-            v3 += XXH_readLE64(p, endian) * PRIME64_2;
-            v3 = XXH_rotl64(v3, 31);
-            v3 *= PRIME64_1;
-            p+=8;
-            v4 += XXH_readLE64(p, endian) * PRIME64_2;
-            v4 = XXH_rotl64(v4, 31);
-            v4 *= PRIME64_1;
-            p+=8;
-        }
-        while (p<=limit);
+        do {
+            v1 = XXH64_round(v1, XXH_readLE64(p, endian)); p+=8;
+            v2 = XXH64_round(v2, XXH_readLE64(p, endian)); p+=8;
+            v3 = XXH64_round(v3, XXH_readLE64(p, endian)); p+=8;
+            v4 = XXH64_round(v4, XXH_readLE64(p, endian)); p+=8;
+        } while (p<=limit);
 
         state->v1 = v1;
         state->v2 = v2;
@@ -850,8 +736,7 @@ FORCE_INLINE XXH_errorcode XXH64_update_endian (XXH64_state_t* state, const void
         state->v4 = v4;
     }
 
-    if (p < bEnd)
-    {
+    if (p < bEnd) {
         XXH_memcpy(state->mem64, p, bEnd-p);
         state->memsize = (int)(bEnd-p);
     }
@@ -874,71 +759,42 @@ XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* state_in, const void*
 FORCE_INLINE U64 XXH64_digest_endian (const XXH64_state_t* state, XXH_endianess endian)
 {
     const BYTE * p = (const BYTE*)state->mem64;
-    const BYTE* bEnd = (const BYTE*)state->mem64 + state->memsize;
+    const BYTE* const bEnd = (const BYTE*)state->mem64 + state->memsize;
     U64 h64;
 
-    if (state->total_len >= 32)
-    {
-        U64 v1 = state->v1;
-        U64 v2 = state->v2;
-        U64 v3 = state->v3;
-        U64 v4 = state->v4;
+    if (state->total_len >= 32) {
+        U64 const v1 = state->v1;
+        U64 const v2 = state->v2;
+        U64 const v3 = state->v3;
+        U64 const v4 = state->v4;
 
         h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18);
-
-        v1 *= PRIME64_2;
-        v1 = XXH_rotl64(v1, 31);
-        v1 *= PRIME64_1;
-        h64 ^= v1;
-        h64 = h64*PRIME64_1 + PRIME64_4;
-
-        v2 *= PRIME64_2;
-        v2 = XXH_rotl64(v2, 31);
-        v2 *= PRIME64_1;
-        h64 ^= v2;
-        h64 = h64*PRIME64_1 + PRIME64_4;
-
-        v3 *= PRIME64_2;
-        v3 = XXH_rotl64(v3, 31);
-        v3 *= PRIME64_1;
-        h64 ^= v3;
-        h64 = h64*PRIME64_1 + PRIME64_4;
-
-        v4 *= PRIME64_2;
-        v4 = XXH_rotl64(v4, 31);
-        v4 *= PRIME64_1;
-        h64 ^= v4;
-        h64 = h64*PRIME64_1 + PRIME64_4;
-    }
-    else
-    {
+        h64 = XXH64_mergeRound(h64, v1);
+        h64 = XXH64_mergeRound(h64, v2);
+        h64 = XXH64_mergeRound(h64, v3);
+        h64 = XXH64_mergeRound(h64, v4);
+    } else {
         h64  = state->seed + PRIME64_5;
     }
 
     h64 += (U64) state->total_len;
 
-    while (p+8<=bEnd)
-    {
-        U64 k1 = XXH_readLE64(p, endian);
-        k1 *= PRIME64_2;
-        k1 = XXH_rotl64(k1,31);
-        k1 *= PRIME64_1;
+    while (p+8<=bEnd) {
+        U64 const k1 = XXH64_round(0, XXH_readLE64(p, endian));
         h64 ^= k1;
-        h64 = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4;
+        h64  = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4;
         p+=8;
     }
 
-    if (p+4<=bEnd)
-    {
+    if (p+4<=bEnd) {
         h64 ^= (U64)(XXH_readLE32(p, endian)) * PRIME64_1;
-        h64 = XXH_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
+        h64  = XXH_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
         p+=4;
     }
 
-    while (p<bEnd)
-    {
+    while (p<bEnd) {
         h64 ^= (*p) * PRIME64_5;
-        h64 = XXH_rotl64(h64, 11) * PRIME64_1;
+        h64  = XXH_rotl64(h64, 11) * PRIME64_1;
         p++;
     }
 
@@ -963,3 +819,36 @@ XXH_PUBLIC_API unsigned long long XXH64_digest (const XXH64_state_t* state_in)
 }
 
 
+/* **************************
+*  Canonical representation
+****************************/
+
+/*! Default XXH result types are basic unsigned 32 and 64 bits.
+*   The canonical representation follows human-readable write convention, aka big-endian (large digits first).
+*   These functions allow transformation of hash result into and from its canonical format.
+*   This way, hash values can be written into a file or buffer, and remain comparable across different systems and programs.
+*/
+
+XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash)
+{
+    XXH_STATIC_ASSERT(sizeof(XXH32_canonical_t) == sizeof(XXH32_hash_t));
+    if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap32(hash);
+    memcpy(dst, &hash, sizeof(*dst));
+}
+
+XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash)
+{
+    XXH_STATIC_ASSERT(sizeof(XXH64_canonical_t) == sizeof(XXH64_hash_t));
+    if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap64(hash);
+    memcpy(dst, &hash, sizeof(*dst));
+}
+
+XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src)
+{
+    return XXH_readBE32(src);
+}
+
+XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src)
+{
+    return XXH_readBE64(src);
+}
diff --git a/programs/xxhash.h b/programs/xxhash.h
index 4b1e1dcd..d6548716 100644
--- a/programs/xxhash.h
+++ b/programs/xxhash.h
@@ -64,7 +64,8 @@ XXH64       13.8 GB/s            1.9 GB/s
 XXH32        6.8 GB/s            6.0 GB/s
 */
 
-#pragma once
+#ifndef XXHASH_H_5627135585666179
+#define XXHASH_H_5627135585666179 1
 
 #if defined (__cplusplus)
 extern "C" {
@@ -138,7 +139,7 @@ regular symbol name will be automatically translated by this header.
 *  Version
 ***************************************/
 #define XXH_VERSION_MAJOR    0
-#define XXH_VERSION_MINOR    5
+#define XXH_VERSION_MINOR    6
 #define XXH_VERSION_RELEASE  0
 #define XXH_VERSION_NUMBER  (XXH_VERSION_MAJOR *100*100 + XXH_VERSION_MINOR *100 + XXH_VERSION_RELEASE)
 XXH_PUBLIC_API unsigned XXH_versionNumber (void);
@@ -147,9 +148,11 @@ XXH_PUBLIC_API unsigned XXH_versionNumber (void);
 /* ****************************
 *  Simple Hash Functions
 ******************************/
+typedef unsigned int       XXH32_hash_t;
+typedef unsigned long long XXH64_hash_t;
 
-XXH_PUBLIC_API unsigned int       XXH32 (const void* input, size_t length, unsigned int seed);
-XXH_PUBLIC_API unsigned long long XXH64 (const void* input, size_t length, unsigned long long seed);
+XXH_PUBLIC_API XXH32_hash_t XXH32 (const void* input, size_t length, unsigned int seed);
+XXH_PUBLIC_API XXH64_hash_t XXH64 (const void* input, size_t length, unsigned long long seed);
 
 /*!
 XXH32() :
@@ -165,23 +168,13 @@ XXH64() :
 
 
 /* ****************************
-*  Advanced Hash Functions
+*  Streaming Hash Functions
 ******************************/
-typedef struct XXH32_state_s XXH32_state_t;   /* incomplete */
-typedef struct XXH64_state_s XXH64_state_t;   /* incomplete */
+typedef struct XXH32_state_s XXH32_state_t;   /* incomplete type */
+typedef struct XXH64_state_s XXH64_state_t;   /* incomplete type */
 
-
-/*!Static allocation
-   For static linking only, do not use in the context of DLL ! */
-typedef struct { long long ll[ 6]; } XXH32_stateBody_t;
-typedef struct { long long ll[11]; } XXH64_stateBody_t;
-
-#define XXH32_CREATESTATE_STATIC(name) XXH32_stateBody_t name##xxhbody; void* name##xxhvoid = &(name##xxhbody); XXH32_state_t* name = (XXH32_state_t*)(name##xxhvoid)   /* no final ; */
-#define XXH64_CREATESTATE_STATIC(name) XXH64_stateBody_t name##xxhbody; void* name##xxhvoid = &(name##xxhbody); XXH64_state_t* name = (XXH64_state_t*)(name##xxhvoid)   /* no final ; */
-
-
-/*!Dynamic allocation
-   To be preferred in the context of DLL */
+/*! Dynamic allocation of states
+    Compatible with dynamic libraries */
 
 XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void);
 XXH_PUBLIC_API XXH_errorcode  XXH32_freeState(XXH32_state_t* statePtr);
@@ -194,11 +187,11 @@ XXH_PUBLIC_API XXH_errorcode  XXH64_freeState(XXH64_state_t* statePtr);
 
 XXH_PUBLIC_API XXH_errorcode XXH32_reset  (XXH32_state_t* statePtr, unsigned int seed);
 XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* input, size_t length);
-XXH_PUBLIC_API unsigned int  XXH32_digest (const XXH32_state_t* statePtr);
+XXH_PUBLIC_API XXH32_hash_t  XXH32_digest (const XXH32_state_t* statePtr);
 
-XXH_PUBLIC_API XXH_errorcode      XXH64_reset  (XXH64_state_t* statePtr, unsigned long long seed);
-XXH_PUBLIC_API XXH_errorcode      XXH64_update (XXH64_state_t* statePtr, const void* input, size_t length);
-XXH_PUBLIC_API unsigned long long XXH64_digest (const XXH64_state_t* statePtr);
+XXH_PUBLIC_API XXH_errorcode XXH64_reset  (XXH64_state_t* statePtr, unsigned long long seed);
+XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* statePtr, const void* input, size_t length);
+XXH_PUBLIC_API XXH64_hash_t  XXH64_digest (const XXH64_state_t* statePtr);
 
 /*!
 These functions generate the xxHash of an input provided in multiple segments,
@@ -213,14 +206,68 @@ Obviously, input must be valid, hence allocated and read accessible.
 The function returns an error code, with 0 meaning OK, and any other value meaning there is an error.
 
 Finally, a hash value can be produced anytime, by using XXHnn_digest().
-This function returns the nn-bits hash.
-It's nonetheless possible to continue inserting input into the hash state
+This function returns the nn-bits hash as an int or long long.
+
+It's still possible to continue inserting input into the hash state after a digest,
 and later on generate some new hashes, by calling again XXHnn_digest().
 
 When done, free XXH state space if it was allocated dynamically.
 */
 
 
+/* **************************
+*  Canonical representation
+****************************/
+typedef struct { unsigned char digest[4]; } XXH32_canonical_t;
+typedef struct { unsigned char digest[8]; } XXH64_canonical_t;
+
+XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash);
+XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash);
+
+XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src);
+XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src);
+
+/*! Default result type for XXH functions are primitive unsigned 32 and 64 bits.
+*   The canonical representation uses human-readable write convention, aka big-endian (large digits first).
+*   These functions allow transformation of hash result into and from its canonical format.
+*   This way, hash values can be written into a file / memory, and remain comparable on different systems and programs.
+*/
+
+
+#ifdef XXH_STATIC_LINKING_ONLY
+
+/* This part contains definition which shall only be used with static linking.
+   The prototypes / types defined here are not guaranteed to remain stable.
+   They could change in a future version, becoming incompatible with a different version of the library */
+
+   struct XXH32_state_s {
+       unsigned long long total_len;
+       unsigned seed;
+       unsigned v1;
+       unsigned v2;
+       unsigned v3;
+       unsigned v4;
+       unsigned mem32[4];   /* buffer defined as U32 for alignment */
+       unsigned memsize;
+   };   /* typedef'd to XXH32_state_t */
+
+   struct XXH64_state_s {
+       unsigned long long total_len;
+       unsigned long long seed;
+       unsigned long long v1;
+       unsigned long long v2;
+       unsigned long long v3;
+       unsigned long long v4;
+       unsigned long long mem64[4];   /* buffer defined as U64 for alignment */
+       unsigned memsize;
+   };   /* typedef'd to XXH64_state_t */
+
+
+#endif
+
+
 #if defined (__cplusplus)
 }
 #endif
+
+#endif /* XXHASH_H_5627135585666179 */
diff --git a/programs/zbufftest.c b/programs/zbufftest.c
index fce0ab27..d0c0503a 100644
--- a/programs/zbufftest.c
+++ b/programs/zbufftest.c
@@ -44,6 +44,7 @@
 #include "zstd_static.h"  /* ZSTD_compressBound(), ZSTD_maxCLevel() */
 #include "zbuff_static.h" /* ZBUFF_createCCtx_advanced */
 #include "datagen.h"      /* RDG_genBuffer */
+#define XXH_STATIC_LINKING_ONLY
 #include "xxhash.h"       /* XXH64 */
 
 
@@ -322,7 +323,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
         size_t cSize, totalTestSize, totalCSize, totalGenSize;
         size_t errorCode;
         U32 n, nbChunks;
-        XXH64_CREATESTATE_STATIC(xxh64);
+        XXH64_state_t xxhState;
         U64 crcOrig;
 
         /* init */
@@ -366,7 +367,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
         }   }
 
         /* multi-segments compression test */
-        XXH64_reset(xxh64, 0);
+        XXH64_reset(&xxhState, 0);
         nbChunks    = (FUZ_rand(&lseed) & 127) + 2;
         for (n=0, cSize=0, totalTestSize=0 ; (n<nbChunks) && (totalTestSize < maxTestSize) ; n++) {
             /* compress random chunk into random size dst buffer */
@@ -378,7 +379,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
                 size_t const compressionError = ZBUFF_compressContinue(zc, cBuffer+cSize, &dstBuffSize, srcBuffer+srcStart, &readChunkSize);
                 CHECK (ZBUFF_isError(compressionError), "compression error : %s", ZBUFF_getErrorName(compressionError));
 
-                XXH64_update(xxh64, srcBuffer+srcStart, readChunkSize);
+                XXH64_update(&xxhState, srcBuffer+srcStart, readChunkSize);
                 memcpy(copyBuffer+totalTestSize, srcBuffer+srcStart, readChunkSize);
                 cSize += dstBuffSize;
                 totalTestSize += readChunkSize;
@@ -399,7 +400,7 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
             CHECK (ZBUFF_isError(flushError), "flush error : %s", ZBUFF_getErrorName(flushError));
             cSize += dstBuffSize;
         }
-        crcOrig = XXH64_digest(xxh64);
+        crcOrig = XXH64_digest(&xxhState);
 
         /* multi - fragments decompression test */
         ZBUFF_decompressInitDictionary(zd, dict, dictSize);

From fb0ba59c41832eeb9c83842b9b580ca14a3503bf Mon Sep 17 00:00:00 2001
From: Yann Collet <yann.collet.73@gmail.com>
Date: Sat, 28 May 2016 15:30:01 +0200
Subject: [PATCH 2/3] Added : utility `roundTripCrash` which generates a crash
 (double-free) on detecting a round-trip corruption

---
 programs/.gitignore       |   1 +
 programs/Makefile         |  12 ++-
 programs/roundTripCrash.c | 185 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 194 insertions(+), 4 deletions(-)
 create mode 100644 programs/roundTripCrash.c

diff --git a/programs/.gitignore b/programs/.gitignore
index 886af777..87e9e530 100644
--- a/programs/.gitignore
+++ b/programs/.gitignore
@@ -9,6 +9,7 @@ zbufftest
 zbufftest32
 datagen
 paramgrill
+roundTripCrash
 
 # Object files
 *.o
diff --git a/programs/Makefile b/programs/Makefile
index c4e19229..debabfde 100644
--- a/programs/Makefile
+++ b/programs/Makefile
@@ -83,7 +83,7 @@ zstd  : $(ZSTD_FILES) $(ZSTD_FILES_LEGACY) $(ZBUFF_FILES) $(ZDICT_FILES) \
 	$(CC)      $(FLAGS) -DZSTD_LEGACY_SUPPORT=$(ZSTD_LEGACY_SUPPORT) $^ -o $@$(EXT)
 
 zstd32: $(ZSTD_FILES) $(ZSTD_FILES_LEGACY) $(ZBUFF_FILES) $(ZDICT_FILES) \
-        zstdcli.c fileio.c bench.c xxhash.c datagen.c dibio.c 
+        zstdcli.c fileio.c bench.c xxhash.c datagen.c dibio.c
 	$(CC) -m32 $(FLAGS) -DZSTD_LEGACY_SUPPORT=$(ZSTD_LEGACY_SUPPORT) $^ -o $@$(EXT)
 
 zstd_nolegacy :
@@ -109,8 +109,8 @@ zstd-compress: $(ZSTDCOMP_FILES) $(ZSTDDIR)/compress/zbuff_compress.c zstdcli.c
 zstd-decompress: $(ZSTDDECOMP_FILES) $(ZSTDDIR)/decompress/zbuff_decompress.c zstdcli.c fileio.c
 	$(CC)      $(FLAGS) -DZSTD_NOBENCH -DZSTD_NODICT -DZSTD_NOCOMPRESS -DZSTD_LEGACY_SUPPORT=0 $^ -o $@$(EXT)
 
-zstd-small: clean 
-	CFLAGS="-Os -s" $(MAKE) zstd-frugal 
+zstd-small: clean
+	CFLAGS="-Os -s" $(MAKE) zstd-frugal
 
 fullbench  : $(ZSTD_FILES) $(ZBUFF_FILES) datagen.c fullbench.c
 	$(CC)      $(FLAGS) $^ -o $@$(EXT)
@@ -141,12 +141,16 @@ paramgrill : $(ZSTD_FILES) \
 datagen : datagen.c datagencli.c
 	$(CC)      $(FLAGS) $^ -o $@$(EXT)
 
+roundTripCrash  : $(ZSTD_FILES) \
+      roundTripCrash.c
+	$(CC)      $(FLAGS) $^ -o $@$(EXT)
+
 clean:
 	@rm -f core *.o tmp* result* *.gcda dictionary *.zst \
         zstd$(EXT) zstd32$(EXT) zstd-compress$(EXT) zstd-decompress$(EXT) \
         fullbench$(EXT) fullbench32$(EXT) \
         fuzzer$(EXT) fuzzer32$(EXT) zbufftest$(EXT) zbufftest32$(EXT) \
-	datagen$(EXT) paramgrill$(EXT)
+        datagen$(EXT) paramgrill$(EXT) roundTripCrash($EXT)
 	@echo Cleaning completed
 
 
diff --git a/programs/roundTripCrash.c b/programs/roundTripCrash.c
new file mode 100644
index 00000000..1b6e1d7b
--- /dev/null
+++ b/programs/roundTripCrash.c
@@ -0,0 +1,185 @@
+/*
+  roundTripCrash
+  Copyright (C) Yann Collet 2013-2016
+
+  GPL v2 License
+
+  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 this program; if not, write to the Free Software Foundation, Inc.,
+  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+  You can contact the author at :
+  - zstd homepage : http://www.zstd.net
+*/
+/*
+  This program takes a file in input,
+  performs a zstd round-trip test (compression - decompress)
+  compares the result with original
+  and generates a crash (double free) on corruption detection.
+*/
+
+/*===========================================
+*   Dependencies
+*==========================================*/
+#include <stddef.h>     /* size_t */
+#include <stdlib.h>     /* malloc, free, exit */
+#include <stdio.h>      /* fprintf */
+#include <sys/types.h>  /* stat */
+#include <sys/stat.h>   /* stat */
+#include "zstd.h"
+
+/** roundTripTest() :
+*   Compresses `srcBuff` into `compressedBuff`,
+*   then decompresses `compressedBuff` into `resultBuff`.
+*   Compression level used is derived from first content byte.
+*   @return : result of decompression, which should be == `srcSize`
+*          or an error code if either compression or decompression fails.
+*   Note : `compressedBuffCapacity` should be `>= ZSTD_compressBound(srcSize)`
+*          for compression to be guaranteed to work */
+static size_t roundTripTest(void* resultBuff, size_t resultBuffCapacity,
+                            void* compressedBuff, size_t compressedBuffCapacity,
+                      const void* srcBuff, size_t srcBuffSize)
+{
+    static const int maxClevel = 19;
+    int const cLevel = (!srcBuffSize) ? 1 : (*(const unsigned char*)srcBuff) % maxClevel;
+    size_t const cSize = ZSTD_compress(compressedBuff, compressedBuffCapacity, srcBuff, srcBuffSize, cLevel);
+    if (ZSTD_isError(cSize)) {
+        fprintf(stderr, "Compression error : %s \n", ZSTD_getErrorName(cSize));
+        return cSize;
+    }
+    return ZSTD_decompress(resultBuff, resultBuffCapacity, compressedBuff, cSize);
+}
+
+
+static size_t checkBuffers(const void* buff1, const void* buff2, size_t buffSize)
+{
+    const char* ip1 = (const char*)buff1;
+    const char* ip2 = (const char*)buff2;
+    size_t pos;
+
+    for (pos=0; pos<buffSize; pos++)
+        if (ip1[pos]!=ip2[pos])
+            break;
+
+    return pos;
+}
+
+
+static void roundTripCheck(const void* srcBuff, size_t srcBuffSize)
+{
+    size_t const cBuffSize = ZSTD_compressBound(srcBuffSize);
+    void* cBuff = malloc(cBuffSize);
+    void* rBuff = malloc(cBuffSize);
+    #define CRASH { free(cBuff); free(cBuff); }   /* double free, to crash program */
+
+    if (!cBuff || !rBuff) {
+        fprintf(stderr, "not enough memory ! \n");
+        exit (1);
+    }
+
+    {   size_t const result = roundTripTest(rBuff, cBuffSize, cBuff, cBuffSize, srcBuff, srcBuffSize);
+        if (ZSTD_isError(result)) {
+            fprintf(stderr, "roundTripTest error : %s \n", ZSTD_getErrorName(result));
+            CRASH;
+        }
+        if (result != srcBuffSize) {
+            fprintf(stderr, "Incorrect regenerated size : %u != %u\n", (unsigned)result, (unsigned)srcBuffSize);
+            CRASH;
+        }
+        if (checkBuffers(srcBuff, rBuff, srcBuffSize) != srcBuffSize) {
+            fprintf(stderr, "Silent decoding corruption !!!");
+            CRASH;
+        }
+    }
+
+    free(cBuff);
+    free(rBuff);
+}
+
+
+static size_t getFileSize(const char* infilename)
+{
+    int r;
+#if defined(_MSC_VER)
+    struct _stat64 statbuf;
+    r = _stat64(infilename, &statbuf);
+    if (r || !(statbuf.st_mode & S_IFREG)) return 0;   /* No good... */
+#else
+    struct stat statbuf;
+    r = stat(infilename, &statbuf);
+    if (r || !S_ISREG(statbuf.st_mode)) return 0;   /* No good... */
+#endif
+    return (size_t)statbuf.st_size;
+}
+
+
+static int isDirectory(const char* infilename)
+{
+    int r;
+#if defined(_MSC_VER)
+    struct _stat64 statbuf;
+    r = _stat64(infilename, &statbuf);
+    if (!r && (statbuf.st_mode & _S_IFDIR)) return 1;
+#else
+    struct stat statbuf;
+    r = stat(infilename, &statbuf);
+    if (!r && S_ISDIR(statbuf.st_mode)) return 1;
+#endif
+    return 0;
+}
+
+
+/** loadFile() :
+*   requirement : `buffer` size >= `fileSize` */
+static void loadFile(void* buffer, const char* fileName, size_t fileSize)
+{
+    FILE* const f = fopen(fileName, "rb");
+    if (isDirectory(fileName)) {
+        fprintf(stderr, "Ignoring %s directory \n", fileName);
+        exit(2);
+    }
+    if (f==NULL) {
+        fprintf(stderr, "Impossible to open %s \n", fileName);
+        exit(3);
+    }
+    {   size_t const readSize = fread(buffer, 1, fileSize, f);
+        if (readSize != fileSize) {
+            fprintf(stderr, "Error reading %s \n", fileName);
+            exit(5);
+    }   }
+    fclose(f);
+}
+
+
+static void fileCheck(const char* fileName)
+{
+    size_t const fileSize = getFileSize(fileName);
+    void* buffer = malloc(fileSize);
+    if (!buffer) {
+        fprintf(stderr, "not enough memory \n");
+        exit(4);
+    }
+    loadFile(buffer, fileName, fileSize);
+    roundTripCheck(buffer, fileSize);
+    free (buffer);
+}
+
+int main(int argCount, const char** argv) {
+    if (argCount < 2) {
+        fprintf(stderr, "Error : no argument : need input file \n");
+        exit(9);
+    }
+    fileCheck(argv[1]);
+    fprintf(stderr, "no pb detected\n");
+    return 0;
+}

From ab2ee0804274187f0ae63ec58fdca389bcbfc0b2 Mon Sep 17 00:00:00 2001
From: Yann Collet <yann.collet.73@gmail.com>
Date: Sat, 28 May 2016 16:06:29 +0200
Subject: [PATCH 3/3] fixed makefile error in clean target

---
 programs/Makefile | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/programs/Makefile b/programs/Makefile
index debabfde..78ffefaf 100644
--- a/programs/Makefile
+++ b/programs/Makefile
@@ -134,15 +134,13 @@ zbufftest32: $(ZSTD_FILES) $(ZBUFF_FILES) \
       datagen.c xxhash.c zbufftest.c
 	$(CC) -m32 $(FLAGS) $^ -o $@$(EXT)
 
-paramgrill : $(ZSTD_FILES) \
-      datagen.c xxhash.c paramgrill.c
+paramgrill : $(ZSTD_FILES) datagen.c xxhash.c paramgrill.c
 	$(CC)      $(FLAGS) $^ -lm -o $@$(EXT)
 
 datagen : datagen.c datagencli.c
 	$(CC)      $(FLAGS) $^ -o $@$(EXT)
 
-roundTripCrash  : $(ZSTD_FILES) \
-      roundTripCrash.c
+roundTripCrash  : $(ZSTD_FILES) roundTripCrash.c
 	$(CC)      $(FLAGS) $^ -o $@$(EXT)
 
 clean:
@@ -150,7 +148,7 @@ clean:
         zstd$(EXT) zstd32$(EXT) zstd-compress$(EXT) zstd-decompress$(EXT) \
         fullbench$(EXT) fullbench32$(EXT) \
         fuzzer$(EXT) fuzzer32$(EXT) zbufftest$(EXT) zbufftest32$(EXT) \
-        datagen$(EXT) paramgrill$(EXT) roundTripCrash($EXT)
+        datagen$(EXT) paramgrill$(EXT) roundTripCrash$(EXT)
 	@echo Cleaning completed