snmplib/int64.c

/** file: test.c - test of 64-bit integer stuff
*
*
* 21-jan-1998: David Perkins <dperkins@dsperkins.com>
*
*/

#include <net-snmp/net-snmp-config.h>
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#if HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#if HAVE_WINSOCK_H
#include <winsock.h>
#endif

#include <net-snmp/types.h>
#include <net-snmp/library/int64.h>

#define TRUE 1
#define FALSE 0

/** divBy10 - divide an unsigned 64-bit integer by 10
*
* call with:
*   u64 - number to be divided
*   pu64Q - location to store quotient
*   puR - location to store remainder
*
*/
void
divBy10(U64 u64, U64 * pu64Q, unsigned int *puR)
{
    unsigned long   ulT;
    unsigned long   ulQ;
    unsigned long   ulR;


    /*
     * top 16 bits 
     */
    ulT = (u64.high >> 16) & 0x0ffff;
    ulQ = ulT / 10;
    ulR = ulT % 10;
    pu64Q->high = ulQ << 16;

    /*
     * next 16 
     */
    ulT = (u64.high & 0x0ffff);
    ulT += (ulR << 16);
    ulQ = ulT / 10;
    ulR = ulT % 10;
    pu64Q->high = pu64Q->high | ulQ;

    /*
     * next 16 
     */
    ulT = ((u64.low >> 16) & 0x0ffff) + (ulR << 16);
    ulQ = ulT / 10;
    ulR = ulT % 10;
    pu64Q->low = ulQ << 16;

    /*
     * final 16 
     */
    ulT = (u64.low & 0x0ffff);
    ulT += (ulR << 16);
    ulQ = ulT / 10;
    ulR = ulT % 10;
    pu64Q->low = pu64Q->low | ulQ;

    *puR = (unsigned int) (ulR);


}                               /* divBy10 */


/** multBy10 - multiply an unsigned 64-bit integer by 10
*
* call with:
*   u64 - number to be multiplied
*   pu64P - location to store product
*
*/
void
multBy10(U64 u64, U64 * pu64P)
{
    unsigned long   ulT;
    unsigned long   ulP;
    unsigned long   ulK;


    /*
     * lower 16 bits 
     */
    ulT = u64.low & 0x0ffff;
    ulP = ulT * 10;
    ulK = ulP >> 16;
    pu64P->low = ulP & 0x0ffff;

    /*
     * next 16 
     */
    ulT = (u64.low >> 16) & 0x0ffff;
    ulP = (ulT * 10) + ulK;
    ulK = ulP >> 16;
    pu64P->low = (ulP & 0x0ffff) << 16 | pu64P->low;

    /*
     * next 16 bits 
     */
    ulT = u64.high & 0x0ffff;
    ulP = (ulT * 10) + ulK;
    ulK = ulP >> 16;
    pu64P->high = ulP & 0x0ffff;

    /*
     * final 16 
     */
    ulT = (u64.high >> 16) & 0x0ffff;
    ulP = (ulT * 10) + ulK;
    ulK = ulP >> 16;
    pu64P->high = (ulP & 0x0ffff) << 16 | pu64P->high;


}                               /* multBy10 */


/** incrByU16 - add an unsigned 16-bit int to an unsigned 64-bit integer
*
* call with:
*   pu64 - number to be incremented
*   u16 - amount to add
*
*/
void
incrByU16(U64 * pu64, unsigned int u16)
{
    unsigned long   ulT1;
    unsigned long   ulT2;
    unsigned long   ulR;
    unsigned long   ulK;


    /*
     * lower 16 bits 
     */
    ulT1 = pu64->low;
    ulT2 = ulT1 & 0x0ffff;
    ulR = ulT2 + u16;
    ulK = ulR >> 16;
    if (ulK == 0) {
        pu64->low = ulT1 + u16;
        return;
    }

    /*
     * next 16 bits 
     */
    ulT2 = (ulT1 >> 16) & 0x0ffff;
    ulR = ulT2 + 1;
    ulK = ulR >> 16;
    if (ulK == 0) {
        pu64->low = ulT1 + u16;
        return;
    }

    /*
     * next 32 - ignore any overflow 
     */
    pu64->low = (ulT1 + u16) & 0x0FFFFFFFFL;
    pu64->high++;

}                               /* incrByV16 */

void
incrByU32(U64 * pu64, unsigned int u32)
{
    unsigned int    tmp;
    tmp = pu64->low;
    pu64->low += u32;
    if (pu64->low < tmp)
        pu64->high++;
}

/*
 * pu64out = pu64one - pu64two 
 */
void
u64Subtract(U64 * pu64one, U64 * pu64two, U64 * pu64out)
{
    if (pu64one->low < pu64two->low) {
        pu64out->low = 0xffffffff - pu64two->low + pu64one->low + 1;
        pu64out->high = pu64one->high - pu64two->high - 1;
    } else {
        pu64out->low = pu64one->low - pu64two->low;
        pu64out->high = pu64one->high - pu64two->high;
    }
}

/** zeroU64 - set an unsigned 64-bit number to zero
*
* call with:
*   pu64 - number to be zero'ed
*
*/
void
zeroU64(U64 * pu64)
{

    pu64->low = 0;
    pu64->high = 0;
}                               /* zeroU64 */


/** isZeroU64 - check if an unsigned 64-bit number is
*
* call with:
*   pu64 - number to be zero'ed
*
*/
int
isZeroU64(U64 * pu64)
{

    if ((pu64->low == 0) && (pu64->high == 0))
        return (TRUE);
    else
        return (FALSE);

}                               /* isZeroU64 */

void
                printU64(char *buf,     /* char [I64CHARSZ+1]; */
                         U64 * pu64) {
    U64             u64a;
    U64             u64b;

    char            aRes[I64CHARSZ + 1];
    unsigned int    u;
    int             j;

    u64a.high = pu64->high;
    u64a.low = pu64->low;
    aRes[I64CHARSZ] = 0;
    for (j = 0; j < I64CHARSZ; j++) {
        divBy10(u64a, &u64b, &u);
        aRes[(I64CHARSZ - 1) - j] = (char) ('0' + u);
        u64a.high = u64b.high;
        u64a.low = u64b.low;
        if (isZeroU64(&u64a))
            break;
    }
    strcpy(buf, &aRes[(I64CHARSZ - 1) - j]);
}

void
                printI64(char *buf,     /* char [I64CHARSZ+1]; */
                         U64 * pu64) {
    U64             u64a;
    U64             u64b;

    char            aRes[I64CHARSZ + 1];
    unsigned int    u;
    int             j, sign = 0;

    if (pu64->high & 0x80000000) {
        u64a.high = ~pu64->high;
        u64a.low = ~pu64->low;
        sign = 1;
        incrByU32(&u64a, 1);    /* bit invert and incr by 1 to print 2s complement */
    } else {
        u64a.high = pu64->high;
        u64a.low = pu64->low;
    }

    aRes[I64CHARSZ] = 0;
    for (j = 0; j < I64CHARSZ; j++) {
        divBy10(u64a, &u64b, &u);
        aRes[(I64CHARSZ - 1) - j] = (char) ('0' + u);
        u64a.high = u64b.high;
        u64a.low = u64b.low;
        if (isZeroU64(&u64a))
            break;
    }
    if (sign == 1) {
        aRes[(I64CHARSZ - 1) - j - 1] = '-';
        strcpy(buf, &aRes[(I64CHARSZ - 1) - j - 1]);
        return;
    }
    strcpy(buf, &aRes[(I64CHARSZ - 1) - j]);
}

int
read64(U64 * i64, const char *string)
{
    U64             i64p;
    unsigned int    u;
    int             sign = 0;
    int             ok = 0;

    zeroU64(i64);
    if (*string == '-') {
        sign = 1;
        string++;
    }

    while (*string && isdigit(*string)) {
        ok = 1;
        u = *string - '0';
        multBy10(*i64, &i64p);
        memcpy(i64, &i64p, sizeof(i64p));
        incrByU16(i64, u);
        string++;
    }
    if (sign) {
        i64->high = ~i64->high;
        i64->low = ~i64->low;
        incrByU16(i64, 1);
    }
    return ok;
}




#ifdef TESTING
void
main(int argc, char *argv[])
{
    int             i;
    int             j;
    int             l;
    unsigned int    u;
    U64             u64a;
    U64             u64b;
#define MXSZ 20
    char            aRes[MXSZ + 1];


    if (argc < 2) {
        printf("This program takes numbers from the command line\n"
               "and prints them out.\n" "Usage: test <unsignedInt>...\n");
        exit(1);
    }

    aRes[MXSZ] = 0;

    for (i = 1; i < argc; i++) {
        l = strlen(argv[i]);
        zeroU64(&u64a);
        for (j = 0; j < l; j++) {
            if (!isdigit(argv[i][j])) {
                printf("Argument is not a number \"%s\"\n", argv[i]);
                exit(1);
            }
            u = argv[i][j] - '0';
            multBy10(u64a, &u64b);
            u64a = u64b;
            incrByU16(&u64a, u);
        }

        printf("number \"%s\" in hex is '%08x%08x'h\n",
               argv[i], u64a.high, u64a.low);

        printf("number is \"%s\"\n", printU64(&u64a));
        for (j = 0; j < MXSZ; j++) {
            divBy10(u64a, &u64b, &u);
            aRes[(MXSZ - 1) - j] = (char) ('0' + u);
            u64a = u64b;
            if (isZeroU64(&u64a))
                break;
        }

        printf("number is \"%s\"\n", &aRes[(MXSZ - 1) - j]);
    }
    exit(0);
}                               /* main */
#endif                          /* TESTING */

/*
 * file: test.c 
 */