xxhash.c 29.4 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912
/*
*  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 :
 * 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.
 * Method 0 (default) : use `memcpy()`. Safe and portable.
 * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable).
 *            This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`.
 * Method 2 : direct access. This method doesn't depend on compiler but violate C standard.
 *            It can generate buggy code on targets which do not support unaligned memory accesses.
 *            But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6)
 * See http://stackoverflow.com/a/32095106/646947 for details.
 * Prefer these methods in priority order (0 > 1 > 2)
 */
#ifndef XXH_FORCE_MEMORY_ACCESS   /* can be defined externally, on command line for example */
#  if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) \
                        || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) \
                        || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) )
#    define XXH_FORCE_MEMORY_ACCESS 2
#  elif defined(__INTEL_COMPILER) || \
  (defined(__GNUC__) && ( defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) \
                    || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) \
                    || defined(__ARM_ARCH_7S__) ))
#    define XXH_FORCE_MEMORY_ACCESS 1
#  endif
#endif

/*!XXH_ACCEPT_NULL_INPUT_POINTER :
 * If input pointer is NULL, xxHash default behavior is to dereference it, triggering a segfault.
 * When this macro is enabled, xxHash actively checks input for null pointer.
 * It it is, result for null input pointers is the same as a null-length input.
 */
#ifndef XXH_ACCEPT_NULL_INPUT_POINTER   /* can be defined externally */
#  define XXH_ACCEPT_NULL_INPUT_POINTER 0
#endif

/*!XXH_FORCE_NATIVE_FORMAT :
 * By default, xxHash library provides endian-independent 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-independence 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.
 */
#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 it to 0 when the input is guaranteed to be aligned,
 * or when alignment doesn't matter for performance.
 */
#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); }
/*! and 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
***************************************/
#ifdef _MSC_VER    /* Visual Studio */
#  pragma warning(disable : 4127)      /* disable: C4127: conditional expression is constant */
#  define FORCE_INLINE static __forceinline
#else
#  if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L   /* C99 */
#    ifdef __GNUC__
#      define FORCE_INLINE static inline __attribute__((always_inline))
#    else
#      define FORCE_INLINE static inline
#    endif
#  else
#    define FORCE_INLINE static
#  endif /* __STDC_VERSION__ */
#endif


/* *************************************
*  Basic Types
***************************************/
#ifndef MEM_MODULE
# if !defined (__VMS) \
  && (defined (__cplusplus) \
  || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
#   include <stdint.h>
    typedef uint8_t  BYTE;
    typedef uint16_t U16;
    typedef uint32_t U32;
# else
    typedef unsigned char      BYTE;
    typedef unsigned short     U16;
    typedef unsigned int       U32;
# endif
#endif

#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2))

/* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */
static U32 XXH_read32(const void* memPtr) { return *(const U32*) memPtr; }

#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==1))

/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
/* currently only defined for gcc and icc */
typedef union { U32 u32; } __attribute__((packed)) unalign;
static U32 XXH_read32(const void* ptr) { return ((const unalign*)ptr)->u32; }

#else

/* portable and safe solution. Generally efficient.
 * see : http://stackoverflow.com/a/32095106/646947
 */
static U32 XXH_read32(const void* memPtr)
{
    U32 val;
    memcpy(&val, memPtr, sizeof(val));
    return val;
}

#endif   /* XXH_FORCE_DIRECT_MEMORY_ACCESS */


/* ****************************************
*  Compiler-specific Functions and Macros
******************************************/
#define XXH_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)

/* Note : although _rotl exists for minGW (GCC under windows), performance seems poor */
#if defined(_MSC_VER)
#  define XXH_rotl32(x,r) _rotl(x,r)
#  define XXH_rotl64(x,r) _rotl64(x,r)
#else
#  define XXH_rotl32(x,r) ((x << r) | (x >> (32 - r)))
#  define XXH_rotl64(x,r) ((x << r) | (x >> (64 - r)))
#endif

#if defined(_MSC_VER)     /* Visual Studio */
#  define XXH_swap32 _byteswap_ulong
#elif XXH_GCC_VERSION >= 403
#  define XXH_swap32 __builtin_bswap32
#else
static U32 XXH_swap32 (U32 x)
{
    return  ((x << 24) & 0xff000000 ) |
            ((x <<  8) & 0x00ff0000 ) |
            ((x >>  8) & 0x0000ff00 ) |
            ((x >> 24) & 0x000000ff );
}
#endif


/* *************************************
*  Architecture Macros
***************************************/
typedef enum { XXH_bigEndian=0, XXH_littleEndian=1 } XXH_endianess;

/* XXH_CPU_LITTLE_ENDIAN can be defined externally, for example on the compiler command line */
#ifndef XXH_CPU_LITTLE_ENDIAN
    static const int g_one = 1;
#   define XXH_CPU_LITTLE_ENDIAN   (*(const char*)(&g_one))
#endif


/* ***************************
*  Memory reads
*****************************/
typedef enum { XXH_aligned, XXH_unaligned } XXH_alignment;

FORCE_INLINE U32 XXH_readLE32_align(const void* ptr, XXH_endianess endian, XXH_alignment align)
{
    if (align==XXH_unaligned)
        return endian==XXH_littleEndian ? XXH_read32(ptr) : XXH_swap32(XXH_read32(ptr));
    else
        return endian==XXH_littleEndian ? *(const U32*)ptr : XXH_swap32(*(const U32*)ptr);
}

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);
}


/* *************************************
*  Macros
***************************************/
#define XXH_STATIC_ASSERT(c)  { enum { XXH_sa = 1/(int)(!!(c)) }; }  /* use after variable declarations */
XXH_PUBLIC_API unsigned XXH_versionNumber (void) { return XXH_VERSION_NUMBER; }


/* *******************************************************************
*  32-bits hash functions
*********************************************************************/
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;

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;
    const BYTE* bEnd = p + len;
    U32 h32;
#define XXH_get32bits(p) XXH_readLE32_align(p, endian, align)

#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1)
    if (p==NULL) {
        len=0;
        bEnd=p=(const BYTE*)(size_t)16;
    }
#endif

    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 = 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 {
        h32  = seed + PRIME32_5;
    }

    h32 += (U32) len;

    while (p+4<=bEnd) {
        h32 += XXH_get32bits(p) * PRIME32_3;
        h32  = XXH_rotl32(h32, 17) * PRIME32_4 ;
        p+=4;
    }

    while (p<bEnd) {
        h32 += (*p) * PRIME32_5;
        h32 = XXH_rotl32(h32, 11) * PRIME32_1 ;
        p++;
    }

    h32 ^= h32 >> 15;
    h32 *= PRIME32_2;
    h32 ^= h32 >> 13;
    h32 *= PRIME32_3;
    h32 ^= h32 >> 16;

    return h32;
}


XXH_PUBLIC_API unsigned int XXH32 (const void* input, size_t len, unsigned int seed)
{
#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);
#else
    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;

    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);
    else
        return XXH32_endian_align(input, len, seed, XXH_bigEndian, XXH_unaligned);
#endif
}



/*======   Hash streaming   ======*/

XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void)
{
    return (XXH32_state_t*)XXH_malloc(sizeof(XXH32_state_t));
}
XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr)
{
    XXH_free(statePtr);
    return XXH_OK;
}

XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dstState, const XXH32_state_t* srcState)
{
    memcpy(dstState, srcState, sizeof(*dstState));
}

XXH_PUBLIC_API XXH_errorcode XXH32_reset(XXH32_state_t* statePtr, unsigned int seed)
{
    XXH32_state_t state;   /* using a local state to memcpy() in order to avoid strict-aliasing warnings */
    memset(&state, 0, sizeof(state));
    state.v1 = seed + PRIME32_1 + PRIME32_2;
    state.v2 = seed + PRIME32_2;
    state.v3 = seed + 0;
    state.v4 = seed - PRIME32_1;
    /* do not write into reserved, planned to be removed in a future version */
    memcpy(statePtr, &state, sizeof(state) - sizeof(state.reserved));
    return XXH_OK;
}


FORCE_INLINE
XXH_errorcode XXH32_update_endian (XXH32_state_t* state, const void* input, size_t len, XXH_endianess endian)
{
    const BYTE* p = (const BYTE*)input;
    const BYTE* const bEnd = p + len;

    if (input==NULL)
#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1)
        return XXH_OK;
#else
        return XXH_ERROR;
#endif

    state->total_len_32 += (unsigned)len;
    state->large_len |= (len>=16) | (state->total_len_32>=16);

    if (state->memsize + len < 16)  {   /* fill in tmp buffer */
        XXH_memcpy((BYTE*)(state->mem32) + state->memsize, input, len);
        state->memsize += (unsigned)len;
        return XXH_OK;
    }

    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 = 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));
        }
        p += 16-state->memsize;
        state->memsize = 0;
    }

    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 = 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;
        state->v3 = v3;
        state->v4 = v4;
    }

    if (p < bEnd) {
        XXH_memcpy(state->mem32, p, (size_t)(bEnd-p));
        state->memsize = (unsigned)(bEnd-p);
    }

    return XXH_OK;
}

XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* state_in, const void* input, size_t len)
{
    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;

    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
        return XXH32_update_endian(state_in, input, len, XXH_littleEndian);
    else
        return XXH32_update_endian(state_in, input, len, XXH_bigEndian);
}



FORCE_INLINE U32 XXH32_digest_endian (const XXH32_state_t* state, XXH_endianess endian)
{
    const BYTE * p = (const BYTE*)state->mem32;
    const BYTE* const bEnd = (const BYTE*)(state->mem32) + state->memsize;
    U32 h32;

    if (state->large_len) {
        h32 = XXH_rotl32(state->v1, 1)
            + XXH_rotl32(state->v2, 7)
            + XXH_rotl32(state->v3, 12)
            + XXH_rotl32(state->v4, 18);
    } else {
        h32 = state->v3 /* == seed */ + PRIME32_5;
    }

    h32 += state->total_len_32;

    while (p+4<=bEnd) {
        h32 += XXH_readLE32(p, endian) * PRIME32_3;
        h32  = XXH_rotl32(h32, 17) * PRIME32_4;
        p+=4;
    }

    while (p<bEnd) {
        h32 += (*p) * PRIME32_5;
        h32  = XXH_rotl32(h32, 11) * PRIME32_1;
        p++;
    }

    h32 ^= h32 >> 15;
    h32 *= PRIME32_2;
    h32 ^= h32 >> 13;
    h32 *= PRIME32_3;
    h32 ^= h32 >> 16;

    return h32;
}


XXH_PUBLIC_API unsigned int XXH32_digest (const XXH32_state_t* state_in)
{
    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;

    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
        return XXH32_digest_endian(state_in, XXH_littleEndian);
    else
        return XXH32_digest_endian(state_in, XXH_bigEndian);
}


/*======   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, remaining comparable across different systems.
*/

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 XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src)
{
    return XXH_readBE32(src);
}


#ifndef XXH_NO_LONG_LONG

/* *******************************************************************
*  64-bits hash functions
*********************************************************************/

/*======   Memory access   ======*/

#ifndef MEM_MODULE
# define MEM_MODULE
# if !defined (__VMS) \
  && (defined (__cplusplus) \
  || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
#   include <stdint.h>
    typedef uint64_t U64;
# else
    /* if compiler doesn't support unsigned long long, replace by another 64-bit type */
    typedef unsigned long long U64;
# endif
#endif


#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2))

/* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */
static U64 XXH_read64(const void* memPtr) { return *(const U64*) memPtr; }

#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==1))

/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
/* currently only defined for gcc and icc */
typedef union { U32 u32; U64 u64; } __attribute__((packed)) unalign64;
static U64 XXH_read64(const void* ptr) { return ((const unalign64*)ptr)->u64; }

#else

/* portable and safe solution. Generally efficient.
 * see : http://stackoverflow.com/a/32095106/646947
 */

static U64 XXH_read64(const void* memPtr)
{
    U64 val;
    memcpy(&val, memPtr, sizeof(val));
    return val;
}

#endif   /* XXH_FORCE_DIRECT_MEMORY_ACCESS */

#if defined(_MSC_VER)     /* Visual Studio */
#  define XXH_swap64 _byteswap_uint64
#elif XXH_GCC_VERSION >= 403
#  define XXH_swap64 __builtin_bswap64
#else
static U64 XXH_swap64 (U64 x)
{
    return  ((x << 56) & 0xff00000000000000ULL) |
            ((x << 40) & 0x00ff000000000000ULL) |
            ((x << 24) & 0x0000ff0000000000ULL) |
            ((x << 8)  & 0x000000ff00000000ULL) |
            ((x >> 8)  & 0x00000000ff000000ULL) |
            ((x >> 24) & 0x0000000000ff0000ULL) |
            ((x >> 40) & 0x000000000000ff00ULL) |
            ((x >> 56) & 0x00000000000000ffULL);
}
#endif

FORCE_INLINE U64 XXH_readLE64_align(const void* ptr, XXH_endianess endian, XXH_alignment align)
{
    if (align==XXH_unaligned)
        return endian==XXH_littleEndian ? XXH_read64(ptr) : XXH_swap64(XXH_read64(ptr));
    else
        return endian==XXH_littleEndian ? *(const U64*)ptr : XXH_swap64(*(const U64*)ptr);
}

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);
}


/*======   xxh64   ======*/

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;

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;
    U64 h64;
#define XXH_get64bits(p) XXH_readLE64_align(p, endian, align)

#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1)
    if (p==NULL) {
        len=0;
        bEnd=p=(const BYTE*)(size_t)32;
    }
#endif

    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 = 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);

    } else {
        h64  = seed + PRIME64_5;
    }

    h64 += (U64) len;

    while (p+8<=bEnd) {
        U64 const k1 = XXH64_round(0, XXH_get64bits(p));
        h64 ^= k1;
        h64  = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4;
        p+=8;
    }

    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) {
        h64 ^= (*p) * PRIME64_5;
        h64 = XXH_rotl64(h64, 11) * PRIME64_1;
        p++;
    }

    h64 ^= h64 >> 33;
    h64 *= PRIME64_2;
    h64 ^= h64 >> 29;
    h64 *= PRIME64_3;
    h64 ^= h64 >> 32;

    return h64;
}


XXH_PUBLIC_API unsigned long long XXH64 (const void* input, size_t len, unsigned long long seed)
{
#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);
#else
    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;

    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);
    else
        return XXH64_endian_align(input, len, seed, XXH_bigEndian, XXH_unaligned);
#endif
}

/*======   Hash Streaming   ======*/

XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void)
{
    return (XXH64_state_t*)XXH_malloc(sizeof(XXH64_state_t));
}
XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr)
{
    XXH_free(statePtr);
    return XXH_OK;
}

XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dstState, const XXH64_state_t* srcState)
{
    memcpy(dstState, srcState, sizeof(*dstState));
}

XXH_PUBLIC_API XXH_errorcode XXH64_reset(XXH64_state_t* statePtr, unsigned long long seed)
{
    XXH64_state_t state;   /* using a local state to memcpy() in order to avoid strict-aliasing warnings */
    memset(&state, 0, sizeof(state));
    state.v1 = seed + PRIME64_1 + PRIME64_2;
    state.v2 = seed + PRIME64_2;
    state.v3 = seed + 0;
    state.v4 = seed - PRIME64_1;
     /* do not write into reserved, planned to be removed in a future version */
    memcpy(statePtr, &state, sizeof(state) - sizeof(state.reserved));
    return XXH_OK;
}

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;
    const BYTE* const bEnd = p + len;

    if (input==NULL)
#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1)
        return XXH_OK;
#else
        return XXH_ERROR;
#endif

    state->total_len += len;

    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) {   /* tmp buffer is full */
        XXH_memcpy(((BYTE*)state->mem64) + state->memsize, input, 32-state->memsize);
        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) {
        const BYTE* const limit = bEnd - 32;
        U64 v1 = state->v1;
        U64 v2 = state->v2;
        U64 v3 = state->v3;
        U64 v4 = state->v4;

        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;
        state->v3 = v3;
        state->v4 = v4;
    }

    if (p < bEnd) {
        XXH_memcpy(state->mem64, p, (size_t)(bEnd-p));
        state->memsize = (unsigned)(bEnd-p);
    }

    return XXH_OK;
}

XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* state_in, const void* input, size_t len)
{
    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;

    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
        return XXH64_update_endian(state_in, input, len, XXH_littleEndian);
    else
        return XXH64_update_endian(state_in, input, len, XXH_bigEndian);
}

FORCE_INLINE U64 XXH64_digest_endian (const XXH64_state_t* state, XXH_endianess endian)
{
    const BYTE * p = (const BYTE*)state->mem64;
    const BYTE* const bEnd = (const BYTE*)state->mem64 + state->memsize;
    U64 h64;

    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);
        h64 = XXH64_mergeRound(h64, v1);
        h64 = XXH64_mergeRound(h64, v2);
        h64 = XXH64_mergeRound(h64, v3);
        h64 = XXH64_mergeRound(h64, v4);
    } else {
        h64  = state->v3 + PRIME64_5;
    }

    h64 += (U64) state->total_len;

    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;
        p+=8;
    }

    if (p+4<=bEnd) {
        h64 ^= (U64)(XXH_readLE32(p, endian)) * PRIME64_1;
        h64  = XXH_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
        p+=4;
    }

    while (p<bEnd) {
        h64 ^= (*p) * PRIME64_5;
        h64  = XXH_rotl64(h64, 11) * PRIME64_1;
        p++;
    }

    h64 ^= h64 >> 33;
    h64 *= PRIME64_2;
    h64 ^= h64 >> 29;
    h64 *= PRIME64_3;
    h64 ^= h64 >> 32;

    return h64;
}

XXH_PUBLIC_API unsigned long long XXH64_digest (const XXH64_state_t* state_in)
{
    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;

    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
        return XXH64_digest_endian(state_in, XXH_littleEndian);
    else
        return XXH64_digest_endian(state_in, XXH_bigEndian);
}


/*====== Canonical representation   ======*/

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 XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src)
{
    return XXH_readBE64(src);
}

#endif  /* XXH_NO_LONG_LONG */