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/*
* Handling of the int64 and uint64 types. Done in 32-bit integers,
* for (pre-C99) portability. Hopefully once C99 becomes widespread
* we can kiss this lot goodbye...
*/
#include <assert.h>
#include <string.h>
#include "int64.h"
uint64 uint64_div10(uint64 x, int *remainder)
{
uint64 y;
unsigned int rem, r2;
y.hi = x.hi / 10;
y.lo = x.lo / 10;
rem = x.lo % 10;
/*
* Now we have to add in the remainder left over from x.hi.
*/
r2 = x.hi % 10;
y.lo += r2 * 429496729;
rem += r2 * 6;
y.lo += rem / 10;
rem %= 10;
if (remainder)
*remainder = rem;
return y;
}
void uint64_decimal(uint64 x, char *buffer)
{
char buf[20];
int start = 20;
int d;
do {
x = uint64_div10(x, &d);
assert(start > 0);
buf[--start] = d + '0';
} while (x.hi || x.lo);
memcpy(buffer, buf + start, sizeof(buf) - start);
buffer[sizeof(buf) - start] = '\0';
}
uint64 uint64_make(unsigned long hi, unsigned long lo)
{
uint64 y;
y.hi = hi & 0xFFFFFFFFU;
y.lo = lo & 0xFFFFFFFFU;
return y;
}
uint64 uint64_add(uint64 x, uint64 y)
{
x.lo = (x.lo + y.lo) & 0xFFFFFFFFU;
x.hi += y.hi + (x.lo < y.lo ? 1 : 0);
return x;
}
uint64 uint64_add32(uint64 x, unsigned long y)
{
uint64 yy;
yy.hi = 0;
yy.lo = y;
return uint64_add(x, yy);
}
int uint64_compare(uint64 x, uint64 y)
{
if (x.hi != y.hi)
return x.hi < y.hi ? -1 : +1;
if (x.lo != y.lo)
return x.lo < y.lo ? -1 : +1;
return 0;
}
uint64 uint64_subtract(uint64 x, uint64 y)
{
x.lo = (x.lo - y.lo) & 0xFFFFFFFFU;
x.hi = (x.hi - y.hi - (x.lo > (y.lo ^ 0xFFFFFFFFU) ? 1 : 0)) & 0xFFFFFFFFU;
return x;
}
double uint64_to_double(uint64 x)
{
return (4294967296.0 * x.hi) + (double)x.lo;
}
uint64 uint64_shift_right(uint64 x, int shift)
{
if (shift < 32) {
x.lo >>= shift;
x.lo |= (x.hi << (32-shift)) & 0xFFFFFFFFU;
x.hi >>= shift;
} else {
x.lo = x.hi >> (shift-32);
x.hi = 0;
}
return x;
}
uint64 uint64_shift_left(uint64 x, int shift)
{
if (shift < 32) {
x.hi = (x.hi << shift) & 0xFFFFFFFFU;
x.hi |= (x.lo >> (32-shift));
x.lo = (x.lo << shift) & 0xFFFFFFFFU;
} else {
x.hi = (x.lo << (shift-32)) & 0xFFFFFFFFU;
x.lo = 0;
}
return x;
}
uint64 uint64_from_decimal(char *str)
{
uint64 ret;
ret.hi = ret.lo = 0;
while (*str >= '0' && *str <= '9') {
ret = uint64_add(uint64_shift_left(ret, 3),
uint64_shift_left(ret, 1));
ret = uint64_add32(ret, *str - '0');
str++;
}
return ret;
}
#ifdef TESTMODE
#include <stdio.h>
int main(void)
{
uint64 x, y, z;
char buf[80];
x = uint64_make(0x3456789AUL, 0xDEF01234UL);
printf("%08lx.%08lx\n", x.hi, x.lo);
uint64_decimal(x, buf);
printf("%s\n", buf);
y = uint64_add32(x, 0xFFFFFFFFU);
printf("%08lx.%08lx\n", y.hi, y.lo);
uint64_decimal(y, buf);
printf("%s\n", buf);
z = uint64_subtract(y, x);
printf("%08lx.%08lx\n", z.hi, z.lo);
uint64_decimal(z, buf);
printf("%s\n", buf);
z = uint64_subtract(x, y);
printf("%08lx.%08lx\n", z.hi, z.lo);
uint64_decimal(z, buf);
printf("%s\n", buf);
y = uint64_shift_right(x, 4);
printf("%08lx.%08lx\n", y.hi, y.lo);
y = uint64_shift_right(x, 36);
printf("%08lx.%08lx\n", y.hi, y.lo);
y = uint64_shift_left(x, 4);
printf("%08lx.%08lx\n", x.hi, x.lo);
y = uint64_shift_left(x, 36);
printf("%08lx.%08lx\n", x.hi, x.lo);
return 0;
}
#endif
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