String GetHashCode from mscorlib (.NET)

main.cpp

#include <iostream>

using namespace std;

typedef unsigned short u16;
typedef unsigned int u32;
typedef int s32;
typedef wchar_t wc;

static s32
getHash32(wc* src, int length)
{
    int hash1 = (5381<<16) + 5381;
    int hash2 = hash1;
    int* pint = (int *)src;
    int len = length;
    while (len > 2)
    {
        hash1 = ((hash1 << 5) + hash1 + (hash1 >> 27)) ^ pint[0];
        hash2 = ((hash2 << 5) + hash2 + (hash2 >> 27)) ^ pint[1];
        pint += 2;
        len  -= 4;
    }

    if (len > 0)
    {
        hash1 = ((hash1 << 5) + hash1 + (hash1 >> 27)) ^ pint[0];
    }
    
    return hash1 + (hash2 * 1566083941);
}

static s32
getHash64(wc* src, int length)
{
    int hash1 = 5381;
    int hash2 = hash1;
    int     c = 0;
    wc *s = src;
    while ((c = s[0]) != 0) {
        hash1 = ((hash1 << 5) + hash1) ^ c;
        c = s[1];
        if (c == 0)
            break;
        hash2 = ((hash2 << 5) + hash2) ^ c;
        s += 2;
    }

    return hash1 + (hash2 * 1566083941);
}

static s32
getHash11(wc* src, int length)
{
    int hash = 5381;
    int c = 0;
    wc* szStr = src;
    
    while ((c = *szStr) != 0) {
        hash = ((hash << 5) + hash) ^ c;
        ++szStr;
    }
    return hash;
}

static s32
getHashMono(wc* src, int length)
{
    wc* chPtr1 = src;
    wc* chPtr2 = chPtr1;
    wc* chPtr3 = chPtr2 + length - 1;
    int num1 = 0;
    while (chPtr2 < chPtr3)
    {
        int num2 = (num1 << 5) - num1 + (int) *chPtr2;
        num1 = (num2 << 5) - num2 + (int) *(chPtr2 + 1);
        chPtr2 += 2;
    }
    wc* chPtr4 = (chPtr3 + 1);
    if (chPtr2 < chPtr4)
        num1 = (num1 << 5) - num1 + (int) *chPtr2;
    return num1;
}

static u16
getHash(wc*src, int length)
{
    return getHashMono(src, length);
}

int main() {
    std::cout << "hash 'yuna' = " << getHash(L"yuna", 4) << endl;
}