101 lines
2.6 KiB
C
101 lines
2.6 KiB
C
#include <limits.h>
|
|
#include <errno.h>
|
|
#include <ctype.h>
|
|
#include "shgetc.h"
|
|
|
|
/* Lookup table for digit values. -1==255>=36 -> invalid */
|
|
static const unsigned char table[] = { -1,
|
|
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
|
|
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
|
|
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
|
|
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,-1,-1,-1,-1,-1,-1,
|
|
-1,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,
|
|
25,26,27,28,29,30,31,32,33,34,35,-1,-1,-1,-1,-1,
|
|
-1,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,
|
|
25,26,27,28,29,30,31,32,33,34,35,-1,-1,-1,-1,-1,
|
|
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
|
|
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
|
|
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
|
|
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
|
|
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
|
|
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
|
|
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
|
|
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
|
|
};
|
|
|
|
unsigned long long __intscan(FILE *f, unsigned base, int pok, unsigned long long lim)
|
|
{
|
|
const unsigned char *val = table+1;
|
|
int c, neg=0;
|
|
unsigned x;
|
|
unsigned long long y;
|
|
if (base > 36 || base == 1) {
|
|
errno = EINVAL;
|
|
return 0;
|
|
}
|
|
while (isspace((c=shgetc(f))));
|
|
if (c=='+' || c=='-') {
|
|
neg = -(c=='-');
|
|
c = shgetc(f);
|
|
}
|
|
if ((base == 0 || base == 16) && c=='0') {
|
|
c = shgetc(f);
|
|
if ((c|32)=='x') {
|
|
c = shgetc(f);
|
|
if (val[c]>=16) {
|
|
shunget(f);
|
|
if (pok) shunget(f);
|
|
else shlim(f, 0);
|
|
return 0;
|
|
}
|
|
base = 16;
|
|
} else if (base == 0) {
|
|
base = 8;
|
|
}
|
|
} else {
|
|
if (base == 0) base = 10;
|
|
if (val[c] >= base) {
|
|
shunget(f);
|
|
shlim(f, 0);
|
|
errno = EINVAL;
|
|
return 0;
|
|
}
|
|
}
|
|
if (base == 10) {
|
|
for (x=0; c-'0'<10U && x<=UINT_MAX/10-1; c=shgetc(f))
|
|
x = x*10 + (c-'0');
|
|
for (y=x; c-'0'<10U && y<=ULLONG_MAX/10 && 10*y<=ULLONG_MAX-(c-'0'); c=shgetc(f))
|
|
y = y*10 + (c-'0');
|
|
if (c-'0'>=10U) goto done;
|
|
} else if (!(base & base-1)) {
|
|
int bs = "\0\1\2\4\7\3\6\5"[(0x17*base)>>5&7];
|
|
for (x=0; val[c]<base && x<=UINT_MAX/32; c=shgetc(f))
|
|
x = x<<bs | val[c];
|
|
for (y=x; val[c]<base && y<=ULLONG_MAX>>bs; c=shgetc(f))
|
|
y = y<<bs | val[c];
|
|
} else {
|
|
for (x=0; val[c]<base && x<=UINT_MAX/36-1; c=shgetc(f))
|
|
x = x*base + val[c];
|
|
for (y=x; val[c]<base && y<=ULLONG_MAX/base && base*y<=ULLONG_MAX-val[c]; c=shgetc(f))
|
|
y = y*base + val[c];
|
|
}
|
|
if (val[c]<base) {
|
|
for (; val[c]<base; c=shgetc(f));
|
|
errno = ERANGE;
|
|
y = lim;
|
|
if (lim&1) neg = 0;
|
|
}
|
|
done:
|
|
shunget(f);
|
|
if (y>=lim) {
|
|
if (!(lim&1) && !neg) {
|
|
errno = ERANGE;
|
|
return lim-1;
|
|
} else if (y>lim) {
|
|
errno = ERANGE;
|
|
return lim;
|
|
}
|
|
}
|
|
return (y^neg)-neg;
|
|
}
|