scanf.h

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/*
 * general implementation of scanf used by scanf, sscanf, fscanf,
 * _cscanf, wscanf, swscanf and fwscanf
 *
 * Copyright 1996,1998 Marcus Meissner
 * Copyright 1996 Jukka Iivonen
 * Copyright 1997,2000, 2003 Uwe Bonnes
 * Copyright 2000 Jon Griffiths
 * Copyright 2002 Daniel Gudbjartsson
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

#ifdef WIDE_SCANF
#define _CHAR_ wchar_t
#define _EOF_ WEOF
#define _EOF_RET WEOF
#define _ISSPACE_(c) iswspace(c)
#define _ISDIGIT_(c) iswdigit(c)
#define _WIDE2SUPPORTED_(c) c /* No conversion needed (wide to wide) */
#define _CHAR2SUPPORTED_(c) c /* FIXME: convert char to wide char */
#define _CHAR2DIGIT_(c, base) wchar2digit((c), (base))
#define _BITMAPSIZE_ 256*256
#else /* WIDE_SCANF */
#define _CHAR_ char
#define _EOF_ EOF
#define _EOF_RET EOF
#define _ISSPACE_(c) isspace(c)
#define _ISDIGIT_(c) isdigit(c)
#define _WIDE2SUPPORTED_(c) c /* FIXME: convert wide char to char */
#define _CHAR2SUPPORTED_(c) c /* No conversion needed (char to char) */
#define _CHAR2DIGIT_(c, base) char2digit((c), (base))
#define _BITMAPSIZE_ 256
#endif /* WIDE_SCANF */

#ifdef CONSOLE
#define _GETC_(file) (consumed++, _getch())
#define _UNGETC_(nch, file) do { _ungetch(nch); consumed--; } while(0)
#define _FUNCTION_ int vcscanf(const char *format, va_list ap)
#else
#ifdef STRING
#undef _EOF_
#define _EOF_ 0
#define _GETC_(file) (consumed++, *file++)
#define _UNGETC_(nch, file) do { file--; consumed--; } while(0)
#ifdef WIDE_SCANF
#define _FUNCTION_ int vswscanf(const wchar_t *file, const wchar_t *format, va_list ap)
#else /* WIDE_SCANF */
#define _FUNCTION_ int vsscanf(const char *file, const char *format, va_list ap)
#endif /* WIDE_SCANF */
#else /* STRING */
#ifdef WIDE_SCANF
#define _GETC_(file) (consumed++, fgetwc(file))
#define _UNGETC_(nch, file) do { ungetwc(nch, file); consumed--; } while(0)
#define _FUNCTION_ int vfwscanf(FILE* file, const wchar_t *format, va_list ap)
#else /* WIDE_SCANF */
#define _GETC_(file) (consumed++, fgetc(file))
#define _UNGETC_(nch, file) do { ungetc(nch, file); consumed--; } while(0)
#define _FUNCTION_ int vfscanf(FILE* file, const char *format, va_list ap)
#endif /* WIDE_SCANF */
#endif /* STRING */
#endif /* CONSOLE */

_FUNCTION_ {
    int rd = 0, consumed = 0;
    int nch;
    if (!*format) return 0;
#ifndef WIDE_SCANF
#ifdef CONSOLE
    TRACE("(%s):\n", debugstr_a(format));
#else /* CONSOLE */
#ifdef STRING
    TRACE("%s (%s)\n", file, debugstr_a(format));
#else /* STRING */
    TRACE("%p (%s)\n", file, debugstr_a(format));
#endif /* STRING */
#endif /* CONSOLE */
#endif /* WIDE_SCANF */
    nch = _GETC_(file);
    if (nch == _EOF_) return _EOF_RET;

    while (*format) {
    /* a whitespace character in the format string causes scanf to read,
     * but not store, all consecutive white-space characters in the input
     * up to the next non-white-space character.  One white space character
     * in the input matches any number (including zero) and combination of
     * white-space characters in the input. */
    if (_ISSPACE_(*format)) {
            /* skip whitespace */
            while ((nch!=_EOF_) && _ISSPACE_(nch))
                nch = _GETC_(file);
        }
    /* a format specification causes scanf to read and convert characters
     * in the input into values of a specified type.  The value is assigned
     * to an argument in the argument list.  Format specifications have
     * the form %[*][width][{h | l | I64 | L}]type */
        else if (*format == '%') {
            int st = 0; int suppress = 0; int width = 0;
        int base;
        int h_prefix = 0;
        int l_prefix = 0;
        int L_prefix = 0;
        int w_prefix = 0;
        int prefix_finished = 0;
        int I64_prefix = 0;
            format++;
        /* look for leading asterisk, which means 'suppress assignment of
         * this field'. */
        if (*format=='*') {
        format++;
        suppress=1;
        }
        /* look for width specification */
        while (_ISDIGIT_(*format)) {
        width*=10;
        width+=*format++ - '0';
        }
        if (width==0) width=-1; /* no width spec seen */
        /* read prefix (if any) */
        while (!prefix_finished) {
        switch(*format) {
        case 'h': h_prefix = 1; break;
        case 'l': l_prefix = 1; break;
        case 'w': w_prefix = 1; break;
        case 'L': L_prefix = 1; break;
        case 'I':
            if (*(format + 1) == '6' &&
            *(format + 2) == '4') {
            I64_prefix = 1;
            format += 2;
            }
            break;
        default:
            prefix_finished = 1;
        }
        if (!prefix_finished) format++;
        }
        /* read type */
            switch(*format) {
        case 'p':
        case 'P': /* pointer. */
                if (sizeof(void *) == sizeof(LONGLONG)) I64_prefix = 1;
                /* fall through */
        case 'x':
        case 'X': /* hexadecimal integer. */
        base = 16;
        goto number;
        case 'o': /* octal integer */
        base = 8;
        goto number;
        case 'u': /* unsigned decimal integer */
        base = 10;
        goto number;
        case 'd': /* signed decimal integer */
        base = 10;
        goto number;
        case 'i': /* generic integer */
        base = 0;
        number: {
            /* read an integer */
            __int64 cur = 0;
            int negative = 0;
            int seendigit=0;
                    /* skip initial whitespace */
                    while ((nch!=_EOF_) && _ISSPACE_(nch))
                        nch = _GETC_(file);
                    /* get sign */
                    if (nch == '-' || nch == '+') {
            negative = (nch=='-');
                        nch = _GETC_(file);
            if (width>0) width--;
                    }
            /* look for leading indication of base */
            if (width!=0 && nch == '0' && *format != 'p' && *format != 'P') {
                        nch = _GETC_(file);
            if (width>0) width--;
            seendigit=1;
            if (width!=0 && (nch=='x' || nch=='X')) {
                if (base==0)
                base=16;
                if (base==16) {
                nch = _GETC_(file);
                if (width>0) width--;
                seendigit=0;
                }
            } else if (base==0)
                base = 8;
            }
            /* format %i without indication of base */
            if (base==0)
            base = 10;
            /* throw away leading zeros */
            while (width!=0 && nch=='0') {
                        nch = _GETC_(file);
            if (width>0) width--;
            seendigit=1;
            }
            if (width!=0 && _CHAR2DIGIT_(nch, base)!=-1) {
            cur = _CHAR2DIGIT_(nch, base);
            nch = _GETC_(file);
            if (width>0) width--;
            seendigit=1;
            }
                    /* read until no more digits */
                    while (width!=0 && (nch!=_EOF_) && _CHAR2DIGIT_(nch, base)!=-1) {
                        cur = cur*base + _CHAR2DIGIT_(nch, base);
                        nch = _GETC_(file);
            if (width>0) width--;
            seendigit=1;
                    }
            /* okay, done! */
            if (!seendigit) break; /* not a valid number */
                    st = 1;
                    if (!suppress) {
#define _SET_NUMBER_(type) *va_arg(ap, type*) = (type)(negative ? -cur : cur)
            if (I64_prefix) _SET_NUMBER_(LONGLONG);
            else if (l_prefix) _SET_NUMBER_(LONG);
            else if (h_prefix) _SET_NUMBER_(short int);
            else _SET_NUMBER_(int);
            }
                }
                break;
        case 'e':
        case 'E':
        case 'f':
        case 'g':
            case 'G': { /* read a float */
                    long double cur = 0;
            int negative = 0;
                    /* skip initial whitespace */
                    while ((nch!=_EOF_) && _ISSPACE_(nch))
                        nch = _GETC_(file);
            /* get sign. */
                    if (nch == '-' || nch == '+') {
            negative = (nch=='-');
            if (width>0) width--;
            if (width==0) break;
                        nch = _GETC_(file);
                    }
            /* get first digit. */
            if ('.' != nch) {
              if (!_ISDIGIT_(nch)) break;
              cur = (nch - '0');
              nch = _GETC_(file);
              if (width>0) width--;
              /* read until no more digits */
              while (width!=0 && (nch!=_EOF_) && _ISDIGIT_(nch)) {
                        cur = cur*10 + (nch - '0');
                        nch = _GETC_(file);
            if (width>0) width--;
              }
            } else {
              cur = 0; /* MaxPayneDemo Fix: .8 -> 0.8 */
            }
            /* handle decimals */
                    if (width!=0 && nch == '.') {
                        long double dec = 1;
                        nch = _GETC_(file);
            if (width>0) width--;
                        while (width!=0 && (nch!=_EOF_) && _ISDIGIT_(nch)) {
                            dec /= 10;
                            cur += dec * (nch - '0');
                            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 ? 0.1f : 10.0f;
            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 msdn,
         * '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 *sptr = suppress ? NULL : va_arg(ap, char*);
                    /* 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 *sptr = suppress ? NULL : va_arg(ap, wchar_t*);
                    /* 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 */
                    char *str = suppress ? NULL : va_arg(ap, char*);
                    if (width == -1) width = 1;
                    while ((width != 0) && (nch != _EOF_))
                    {
                        if (!suppress) *str++ = _CHAR2SUPPORTED_(nch);
                        st++;
                        width--;
                        nch = _GETC_(file);
                    }
                }
        break;
      widecharacter: { /* read single character into a wchar_t */
                    wchar_t *str = suppress ? NULL : va_arg(ap, wchar_t*);
                    if (width == -1) width = 1;
                    while ((width != 0) && (nch != _EOF_))
                    {
                        if (!suppress) *str++ = _WIDE2SUPPORTED_(nch);
                        st++;
                        width--;
                        nch = _GETC_(file);
                    }
            }
        break;
        case 'n': {
            if (!suppress) {
            int*n = va_arg(ap, int*);
            *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 */
#ifdef _LIBCNT_
            Mask = RtlAllocateHeap(RtlGetProcessHeap(), HEAP_ZERO_MEMORY, _BITMAPSIZE_/8);
#else
            Mask = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, _BITMAPSIZE_/8);
#endif
            RtlInitializeBitMap(&bitMask, Mask, _BITMAPSIZE_);

            /* Read the format */
            format++;
            if(*format == '^') {
            invert = 1;
            format++;
            }
            if(*format == ']') {
            RtlSetBits(&bitMask, ']', 1);
            format++;
            }
                    while(*format && (*format != ']')) {
            /* According to msdn:
             * "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;
#ifdef _LIBCNT_
            RtlFreeHeap(RtlGetProcessHeap(), 0, Mask);
#else
            HeapFree(GetProcessHeap(), 0, Mask);
#endif
                }
                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);
    }
    TRACE("returning %d\n", rd);
    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_