kagbuildnumber.cpp

#include <cstdlib>
#include <cstdio>

int StringEqualUntil(const char* s1, const char* s2, int n)
{
    int c1, c2;

    while (1)
    {
        c1 =  *s1++;
        c2 =  *s2++;

        if (!n--)
        {
            return 0;
        } // strings are equal until end point

        if (c1 != c2)
        {
            if (c1 >= 'a' && c1 <= 'z')
            {
                c1 -= ('a' - 'A');
            }

            if (c2 >= 'a' && c2 <= 'z')
            {
                c2 -= ('a' - 'A');
            }

            if (c1 != c2)
            {
                return  - 1;
            } // strings not equal
        }

        if (!c1)
        {
            return 0;
        } // strings are equal
    }

    return  - 1;
}

int MakeBuildNumber(char* date)
{
    static const char* mon[12] =
    {
        "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
    };
    char mond[12] =
    {
        31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
    };
    int m = 0;
    int d = 0;
    int y = 0;
    int b;

    for (m = 0; m < 11; m++)
    {
        if (StringEqualUntil(&date[0], mon[m], 3) == 0)
        {
            break;
        }

        d += mond[m];
    }

    d += atoi(&date[4]) - 1;
    y = atoi(&date[7]) - 1900;
    b = d + (int)((y - 1) *365.25);

    if (((y % 4) == 0) && m > 1)
    {
        b += 1;
    }

    b -= 40284; // Apr 17 2011
    return b;
}

int main()
{
        char date[] = __DATE__;
        int buildnum = MakeBuildNumber( date );

        printf("%d\n", buildnum);
}