snmplib/int64.c

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

#include <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 "asn1.h"
#include "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 */