📄 vfscanf.cxx
字号:
case 'f':
/* no need to fix base here */
if (base <= 10)
break; /* not legal here */
flags &= ~(SIGNOK | PFXOK | NDIGITS);
goto ok;
/* sign ok only as first character */
case '+':
case '-':
if (flags & SIGNOK)
{
flags &= ~SIGNOK;
goto ok;
}
break;
/* x ok iff flag still set & 2nd char */
case 'x':
case 'X':
if (flags & PFXOK && p == buf + 1)
{
base = 16;/* if %i */
flags &= ~PFXOK;
goto ok;
}
break;
}
/*
* If we got here, c is not a legal character
* for a number. Stop accumulating digits.
*/
break;
ok:
/*
* c is legal: store it and look at the next.
*/
*p++ = c;
INC_CURR_POS;
if (SPACE_LEFT == 0)
#ifndef REDHAT_NEC
if (REFILL)
#endif
break; /* EOF */
}
/*
* If we had only a sign, it is no good; push back the sign.
* If the number ends in `x', it was [sign] '0' 'x', so push
* back the x and treat it as [sign] '0'.
*/
if (flags & NDIGITS)
{
if (p > buf)
_CAST_VOID ungetc (*(u_char *)-- p, fp);
goto match_failure;
}
c = ((u_char *) p)[-1];
if (c == 'x' || c == 'X')
{
--p;
/*(void)*/ ungetc (c, fp);
}
if ((flags & SUPPRESS) == 0)
{
u_long res;
*p = 0;
res = (*ccfn) (buf, (char **) NULL, base);
if (flags & POINTER)
*(va_arg (ap, char **)) = (char *) (CYG_ADDRESS) res;
else if (flags & SHORT)
{
sp = va_arg (ap, short *);
*sp = res;
}
else if (flags & LONG)
{
lp = va_arg (ap, long *);
*lp = res;
}
else
{
ip = va_arg (ap, int *);
*ip = res;
}
nassigned++;
}
nread += p - buf;
break;
case CT_FLOAT:
/* scan a floating point number as if by strtod */
#ifdef hardway
if (width == 0 || width > sizeof (buf) - 1)
width = sizeof (buf) - 1;
#else
/* size_t is unsigned, hence this optimisation */
if (--width > sizeof (buf) - 2)
width = sizeof (buf) - 2;
width++;
#endif // ifdef hardway
flags |= SIGNOK | NDIGITS | DPTOK | EXPOK;
for (p = buf; width; width--)
{
c = *CURR_POS;
/*
* This code mimicks the integer conversion
* code, but is much simpler.
*/
switch (c)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
flags &= ~(SIGNOK | NDIGITS);
goto fok;
case '+':
case '-':
if (flags & SIGNOK)
{
flags &= ~SIGNOK;
goto fok;
}
break;
case '.':
if (flags & DPTOK)
{
flags &= ~(SIGNOK | DPTOK);
goto fok;
}
break;
case 'e':
case 'E':
/* no exponent without some digits */
if ((flags & (NDIGITS | EXPOK)) == EXPOK)
{
flags =
(flags & ~(EXPOK | DPTOK)) |
SIGNOK | NDIGITS;
goto fok;
}
break;
}
break;
fok:
*p++ = c;
INC_CURR_POS;
if (SPACE_LEFT == 0)
#ifndef REDHAT_NEC
if (REFILL)
#endif
break; /* EOF */
}
/*
* If no digits, might be missing exponent digits
* (just give back the exponent) or might be missing
* regular digits, but had sign and/or decimal point.
*/
if (flags & NDIGITS)
{
if (flags & EXPOK)
{
/* no digits at all */
while (p > buf)
ungetc (*(u_char *)-- p, fp);
goto match_failure;
}
/* just a bad exponent (e and maybe sign) */
c = *(u_char *)-- p;
if (c != 'e' && c != 'E')
{
_CAST_VOID ungetc (c, fp); /* sign */
c = *(u_char *)-- p;
}
_CAST_VOID ungetc (c, fp);
}
if ((flags & SUPPRESS) == 0)
{
double res;
*p = 0;
#ifdef CYGSEM_LIBC_STDIO_SCANF_FLOATING_POINT
res = atof (buf);
#else
res = 0.0;
#endif
if (flags & LONG)
{
dp = va_arg (ap, double *);
*dp = res;
}
else if (flags & LONGDBL)
{
ldp = va_arg (ap, long double *);
*ldp = res;
}
else
{
flp = va_arg (ap, float *);
*flp = res;
}
nassigned++;
}
nread += p - buf;
break;
}
}
input_failure:
return nassigned ? nassigned : -1;
match_failure:
return nassigned;
} // vfscanf()
/*
* Fill in the given table from the scanset at the given format
* (just after `['). Return a pointer to the character past the
* closing `]'. The table has a 1 wherever characters should be
* considered part of the scanset.
*/
/*static*/
u_char *
__sccl (char *tab, u_char *fmt)
{
int c, n, v;
/* first `clear' the whole table */
c = *fmt++; /* first char hat => negated scanset */
if (c == '^')
{
v = 1; /* default => accept */
c = *fmt++; /* get new first char */
}
else
v = 0; /* default => reject */
/* should probably use memset here */
for (n = 0; n < 256; n++)
tab[n] = v;
if (c == 0)
return fmt - 1; /* format ended before closing ] */
/*
* Now set the entries corresponding to the actual scanset to the
* opposite of the above.
*
* The first character may be ']' (or '-') without being special; the
* last character may be '-'.
*/
v = 1 - v;
for (;;)
{
tab[c] = v; /* take character c */
doswitch:
n = *fmt++; /* and examine the next */
switch (n)
{
case 0: /* format ended too soon */
return fmt - 1;
case '-':
/*
* A scanset of the form [01+-] is defined as `the digit 0, the
* digit 1, the character +, the character -', but the effect
* of a scanset such as [a-zA-Z0-9] is implementation defined.
* The V7 Unix scanf treats `a-z' as `the letters a through z',
* but treats `a-a' as `the letter a, the character -, and the
* letter a'.
*
* For compatibility, the `-' is not considerd to define a
* range if the character following it is either a close
* bracket (required by ANSI) or is not numerically greater
* than the character we just stored in the table (c).
*/
n = *fmt;
if (n == ']' || n < c)
{
c = '-';
break; /* resume the for(;;) */
}
fmt++;
do
{ /* fill in the range */
tab[++c] = v;
}
while (c < n);
#if 1 /* XXX another disgusting compatibility hack */
/*
* Alas, the V7 Unix scanf also treats formats such
* as [a-c-e] as `the letters a through e'. This too
* is permitted by the standard....
*/
goto doswitch;
#else
c = *fmt++;
if (c == 0)
return fmt - 1;
if (c == ']')
return fmt;
#endif
break;
case ']': /* end of scanset */
return fmt;
default: /* just another character */
c = n;
break;
}
}
/* NOTREACHED */
} // __sccl()
#endif // if defined(CYGFUN_LIBC_STDIO_ungetc)
// EOF vfscanf.cxx
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