📄 scanf.h
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nch = _GETC_(file);
if (width>0) width--;
}
}
/* handle exponent */
if (width!=0 && (nch == 'e' || nch == 'E')) {
int exponent = 0, negexp = 0;
float expcnt;
nch = _GETC_(file);
if (width>0) width--;
/* possible sign on the exponent */
if (width!=0 && (nch=='+' || nch=='-')) {
negexp = (nch=='-');
nch = _GETC_(file);
if (width>0) width--;
}
/* exponent digits */
while (width!=0 && (nch!=_EOF_) && _ISDIGIT_(nch)) {
exponent *= 10;
exponent += (nch - '0');
nch = _GETC_(file);
if (width>0) width--;
}
/* update 'cur' with this exponent. */
expcnt = negexp ? .1 : 10;
while (exponent!=0) {
if (exponent&1)
cur*=expcnt;
exponent/=2;
expcnt=expcnt*expcnt;
}
}
st = 1;
if (!suppress) {
if (L_prefix) _SET_NUMBER_(long double);
else if (l_prefix) _SET_NUMBER_(double);
else _SET_NUMBER_(float);
}
}
break;
/* According to
* http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vclib/html/_crt_scanf_type_field_characters.asp
* 's' reads a character string in a call to fscanf
* and 'S' a wide character string and vice versa in a
* call to fwscanf. The 'h', 'w' and 'l' prefixes override
* this behaviour. 'h' forces reading char * but 'l' and 'w'
* force reading WCHAR. */
case 's':
if (w_prefix || l_prefix) goto widecharstring;
else if (h_prefix) goto charstring;
#ifdef WIDE_SCANF
else goto widecharstring;
#else /* WIDE_SCANF */
else goto charstring;
#endif /* WIDE_SCANF */
case 'S':
if (w_prefix || l_prefix) goto widecharstring;
else if (h_prefix) goto charstring;
#ifdef WIDE_SCANF
else goto charstring;
#else /* WIDE_SCANF */
else goto widecharstring;
#endif /* WIDE_SCANF */
charstring: { /* read a word into a char */
char*str = suppress ? NULL : va_arg(ap, char*);
char*sptr = str;
/* skip initial whitespace */
while ((nch!=_EOF_) && _ISSPACE_(nch))
nch = _GETC_(file);
/* read until whitespace */
while (width!=0 && (nch!=_EOF_) && !_ISSPACE_(nch)) {
if (!suppress) *sptr++ = _CHAR2SUPPORTED_(nch);
st++;
nch = _GETC_(file);
if (width>0) width--;
}
/* terminate */
if (!suppress) *sptr = 0;
}
break;
widecharstring: { /* read a word into a wchar_t* */
wchar_t*str =
suppress ? NULL : va_arg(ap, wchar_t*);
wchar_t*sptr = str;
/* skip initial whitespace */
while ((nch!=_EOF_) && _ISSPACE_(nch))
nch = _GETC_(file);
/* read until whitespace */
while (width!=0 && (nch!=_EOF_) && !_ISSPACE_(nch)) {
if (!suppress) *sptr++ = _WIDE2SUPPORTED_(nch);
st++;
nch = _GETC_(file);
if (width>0) width--;
}
/* terminate */
if (!suppress) *sptr = 0;
}
break;
/* 'c' and 'C work analogously to 's' and 'S' as described
* above */
case 'c':
if (w_prefix || l_prefix) goto widecharacter;
else if (h_prefix) goto character;
#ifdef WIDE_SCANF
else goto widecharacter;
#else /* WIDE_SCANF */
else goto character;
#endif /* WIDE_SCANF */
case 'C':
if (w_prefix || l_prefix) goto widecharacter;
else if (h_prefix) goto character;
#ifdef WIDE_SCANF
else goto character;
#else /* WIDE_SCANF */
else goto widecharacter;
#endif /* WIDE_SCANF */
character: { /* read single character into char */
if (nch!=_EOF_) {
if (!suppress) {
char*c = va_arg(ap, char*);
*c = _CHAR2SUPPORTED_(nch);
}
st = 1;
nch = _GETC_(file);
}
}
break;
widecharacter: { /* read single character into a wchar_t */
if (nch!=_EOF_) {
if (!suppress) {
wchar_t*c = va_arg(ap, wchar_t*);
*c = _WIDE2SUPPORTED_(nch);
}
nch = _GETC_(file);
st = 1;
}
}
break;
case 'n': {
if (!suppress) {
int*n = va_arg(ap, int*);
/*
*n = consumed - (nch!=_EOF_);
FIXME: The above is the Wine version and it doesnt work in ros
when %n is at end of input string (return one too many).
But does it fail in Wine too?? If so wine also needs fixin.
-Gunnar
*/
*n = consumed - 1;
}
/* This is an odd one: according to the standard,
* "Execution of a %n directive does not increment the
* assignment count returned at the completion of
* execution" even if it wasn't suppressed with the
* '*' flag. The Corrigendum to the standard seems
* to contradict this (comment out the assignment to
* suppress below if you want to implement these
* alternate semantics) but the windows program I'm
* looking at expects the behavior I've coded here
* (which happens to be what glibc does as well).
*/
suppress = 1;
st = 1;
}
break;
case '[': {
_CHAR_ *str = suppress ? NULL : va_arg(ap, _CHAR_*);
_CHAR_ *sptr = str;
RTL_BITMAP bitMask;
ULONG *Mask;
int invert = 0; /* Set if we are NOT to find the chars */
/* Init our bitmap */
Mask = RtlAllocateHeap(RtlGetProcessHeap(), HEAP_ZERO_MEMORY, _BITMAPSIZE_/8);
RtlInitializeBitMap(&bitMask, Mask, _BITMAPSIZE_);
/* Read the format */
format++;
if(*format == '^') {
invert = 1;
format++;
}
if(*format == ']') {
RtlSetBits(&bitMask, ']', 1);
format++;
}
while(*format && (*format != ']')) {
/* According to:
* http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vccore98/html/_crt_scanf_width_specification.asp
* "Note that %[a-z] and %[z-a] are interpreted as equivalent to %[abcde...z]." */
if((*format == '-') && (*(format + 1) != ']')) {
if ((*(format - 1)) < *(format + 1))
RtlSetBits(&bitMask, *(format - 1) +1 , *(format + 1) - *(format - 1));
else
RtlSetBits(&bitMask, *(format + 1) , *(format - 1) - *(format + 1));
format++;
} else
RtlSetBits(&bitMask, *format, 1);
format++;
}
/* read until char is not suitable */
while ((width != 0) && (nch != _EOF_)) {
if(!invert) {
if(RtlAreBitsSet(&bitMask, nch, 1)) {
if (!suppress) *sptr++ = _CHAR2SUPPORTED_(nch);
} else
break;
} else {
if(RtlAreBitsClear(&bitMask, nch, 1)) {
if (!suppress) *sptr++ = _CHAR2SUPPORTED_(nch);
} else
break;
}
st++;
nch = _GETC_(file);
if (width>0) width--;
}
/* terminate */
if (!suppress) *sptr = 0;
RtlFreeHeap(RtlGetProcessHeap(), 0, Mask);
}
break;
default:
/* From spec: "if a percent sign is followed by a character
* that has no meaning as a format-control character, that
* character and the following characters are treated as
* an ordinary sequence of characters, that is, a sequence
* of characters that must match the input. For example,
* to specify that a percent-sign character is to be input,
* use %%." */
while ((nch!=_EOF_) && _ISSPACE_(nch))
nch = _GETC_(file);
if (nch==*format) {
suppress = 1; /* whoops no field to be read */
st = 1; /* but we got what we expected */
nch = _GETC_(file);
}
break;
}
if (st && !suppress) rd++;
else if (!st) break;
}
/* a non-white-space character causes scanf to read, but not store,
* a matching non-white-space character. */
else {
/* check for character match */
if (nch == *format) {
nch = _GETC_(file);
} else break;
}
format++;
}
if (nch!=_EOF_) {
_UNGETC_(nch, file);
}
return rd;
}
#undef _CHAR_
#undef _EOF_
#undef _EOF_RET
#undef _ISSPACE_
#undef _ISDIGIT_
#undef _CHAR2SUPPORTED_
#undef _WIDE2SUPPORTED_
#undef _CHAR2DIGIT_
#undef _GETC_
#undef _UNGETC_
#undef _FUNCTION_
#undef _BITMAPSIZE_
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