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#include <u.h>
#include <libc.h>
#include <stdio.h>
/*
* try all combination of flags and float conversions
* with some different widths & precisions
*/
#define Njust 2
#define Nplus 3
#define Nalt 2
#define Nzero 2
#define Nspec 5
#define Nwidth 5
#define Nprec 5
static double fmtvals[] = {
3.1415925535897932e15,
3.1415925535897932e14,
3.1415925535897932e13,
3.1415925535897932e12,
3.1415925535897932e11,
3.1415925535897932e10,
3.1415925535897932e9,
3.1415925535897932e8,
3.1415925535897932e7,
3.1415925535897932e6,
3.1415925535897932e5,
3.1415925535897932e4,
3.1415925535897932e3,
3.1415925535897932e2,
3.1415925535897932e1,
3.1415925535897932e0,
3.1415925535897932e-1,
3.1415925535897932e-2,
3.1415925535897932e-3,
3.1415925535897932e-4,
3.1415925535897932e-5,
3.1415925535897932e-6,
3.1415925535897932e-7,
3.1415925535897932e-8,
3.1415925535897932e-9,
3.1415925535897932e-10,
3.1415925535897932e-11,
3.1415925535897932e-12,
3.1415925535897932e-13,
3.1415925535897932e-14,
3.1415925535897932e-15,
};
/*
* are the numbers close?
* used to compare long numbers where the last few digits are garbage
* due to precision problems
*/
static int
numclose(char *num1, char *num2)
{
int ndig;
double d1, d2;
enum { MAXDIG = 15 };
d1 = fmtstrtod(num1, 0);
d2 = fmtstrtod(num2, 0);
if(d1 != d2)
return 0;
ndig = 0;
while (*num1) {
if (*num1 >= '0' && *num1 <= '9') {
ndig++;
if (ndig > MAXDIG) {
if (!(*num2 >= '0' && *num2 <= '9')) {
return 0;
}
} else if (*num1 != *num2) {
return 0;
}
} else if (*num1 != *num2) {
return 0;
} else if (*num1 == 'e' || *num1 == 'E') {
ndig = 0;
}
num1++;
num2++;
}
if (*num1 || !num2)
return 0;
return 1;
}
static void
doit(int just, int plus, int alt, int zero, int width, int prec, int spec)
{
char format[256];
char *p;
const char *s;
int i;
p = format;
*p++ = '%';
if (just > 0)
*p++ = "-"[just - 1];
if (plus > 0)
*p++ = "+ "[plus - 1];
if (alt > 0)
*p++ = "#"[alt - 1];
if (zero > 0)
*p++ = "0"[zero - 1];
s = "";
switch (width) {
case 1: s = "1"; break;
case 2: s = "5"; break;
case 3: s = "10"; break;
case 4: s = "15"; break;
}
strcpy(p, s);
s = "";
switch (prec) {
case 1: s = ".0"; break;
case 2: s = ".2"; break;
case 3: s = ".5"; break;
case 4: s = ".15"; break;
}
strcat(p, s);
p = strchr(p, '\0');
*p++ = "efgEG"[spec];
*p = '\0';
for (i = 0; i < sizeof(fmtvals) / sizeof(fmtvals[0]); i++) {
char ref[1024], buf[1024];
Rune rbuf[1024];
double d1, d2;
sprintf(ref, format, fmtvals[i]);
snprint(buf, sizeof(buf), format, fmtvals[i]);
if (strcmp(ref, buf) != 0
&& !numclose(ref, buf)) {
d1 = fmtstrtod(ref, 0);
d2 = fmtstrtod(buf, 0);
fprintf(stderr, "%s: ref='%s'%s fmt='%s'%s\n",
format,
ref, d1==fmtvals[i] ? "" : " (ref is inexact!)",
buf, d2==fmtvals[i] ? "" : " (fmt is inexact!)");
// exits("oops");
}
/* Check again with output to rune string */
runesnprint(rbuf, 1024, format, fmtvals[i]);
snprint(buf, sizeof(buf), "%S", rbuf);
if (strcmp(ref, buf) != 0
&& !numclose(ref, buf)) {
d1 = fmtstrtod(ref, 0);
d2 = fmtstrtod(buf, 0);
fprintf(stderr, "%s: ref='%s'%s fmt='%s'%s\n",
format,
ref, d1==fmtvals[i] ? "" : " (ref is inexact!)",
buf, d2==fmtvals[i] ? "" : " (fmt is inexact!)");
// exits("oops");
}
}
}
void
main(int argc, char **argv)
{
int just, plus, alt, zero, width, prec, spec;
for (just = 0; just < Njust; just++)
for (plus = 0; plus < Nplus; plus++)
for (alt = 0; alt < Nalt; alt++)
for (zero = 0; zero < Nzero; zero++)
for (width = 0; width < Nwidth; width++)
for (prec = 0; prec < Nprec; prec++)
for (spec = 0; spec < Nspec; spec++)
doit(just, plus, alt, zero, width, prec, spec);
exits(0);
}
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