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/* cheap ecvt replacement */
#include "config.h"
#include <math.h>
extern double floor(double);
extern double pow10(double);
#define MAXCONV 0x40
char scratch[MAXCONV];
char* ecvt(double x, int len, int* exp, int* sign)
{
int i, j;
double z;
if(len > (MAXCONV-1)) len = MAXCONV-1;
if(x<0)
{
*sign = 1;
x = -x;
}
else
{
*sign = 0;
}
if(x==0)
*exp=-1;
else
*exp=(int)floor(log10(x));
x = x / pow10((double)*exp);
*exp += 1;
for(i=0; i < len; i++)
{
z=floor(x);
scratch[i]='0'+(char)((int)z);
x = (x-z)*10;
}
if((x >= 5) && i)
{
for(j=i-1; j>=0; j--)
{
if(scratch[j]!='9')
{
scratch[j]+=1; break;
}
else
{
scratch[j]='0';
}
}
if(j==0)
{
scratch[0]='1';
*exp += 1;
}
}
scratch[i]='\0';
return scratch;
}
#ifdef TEST
int main(int argc, char ** argv)
{
int a, b;
char * conv=ecvt(PI*1e10,20,&a,&b);
printf("ecvt Test: %f -> %s, %d, %d\n",PI,conv,a,b);
}
#endif
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