xref: /device/linaro/bootloader/edk2/StdLib/LibC/Stdio/vfscanf.c

/** @file
    Implementation of scanf internals for <stdio.h>.

    Copyright (c) 2010 - 2014, Intel Corporation. All rights reserved.<BR>
    This program and the accompanying materials are licensed and made available
    under the terms and conditions of the BSD License that accompanies this
    distribution.  The full text of the license may be found at
    http://opensource.org/licenses/bsd-license.

    THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
    WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

    Copyright (c) 1990, 1993
    The Regents of the University of California.  All rights reserved.

    This code is derived from software contributed to Berkeley by
    Chris Torek.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
    are met:
      - Redistributions of source code must retain the above copyright
        notice, this list of conditions and the following disclaimer.
      - Redistributions in binary form must reproduce the above copyright
        notice, this list of conditions and the following disclaimer in the
        documentation and/or other materials provided with the distribution.
      - Neither the name of the University nor the names of its contributors
        may be used to endorse or promote products derived from this software
        without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
    LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.

    NetBSD: vfscanf.c,v 1.37.4.1 2007/05/07 19:49:08 pavel Exp
    FreeBSD: src/lib/libc/stdio/vfscanf.c,v 1.41 2007/01/09 00:28:07 imp Exp
    vfscanf.c 8.1 (Berkeley) 6/4/93
**/
#include  <LibConfig.h>

#include "namespace.h"
#include <assert.h>
#include <ctype.h>
#include  <errno.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdarg.h>
#include <string.h>
#include  <sys/types.h>
#include <wchar.h>
#include <wctype.h>

#include "reentrant.h"
#include "local.h"

#ifndef NO_FLOATING_POINT
#include <locale.h>
#endif

/*
 * Provide an external name for vfscanf.  Note, EFI uses the normal
 * namespace.h method; stdio routines explicitly use the internal name
 * __svfscanf.
 */
#ifdef __weak_alias
__weak_alias(vfscanf,__svfscanf)
#endif

#define BUF   513 /* Maximum length of numeric string. */

/*
 * Flags used during conversion.
 */
#define LONG        0x0001  /* l: long or double */
#define LONGDBL     0x0002  /* L: long double */
#define SHORT       0x0004  /* h: short */
#define SUPPRESS    0x0008  /* *: suppress assignment */
#define POINTER     0x0010  /* p: void * (as hex) */
#define NOSKIP      0x0020  /* [ or c: do not skip blanks */
#define LONGLONG    0x0400  /* ll: long long (+ deprecated q: quad) */
#define INTMAXT     0x0800  /* j: intmax_t */
#define PTRDIFFT    0x1000  /* t: ptrdiff_t */
#define SIZET       0x2000  /* z: size_t */
#define SHORTSHORT  0x4000  /* hh: char */
#define UNSIGNED    0x8000  /* %[oupxX] conversions */

/*
 * The following are used in integral conversions only:
 * SIGNOK, NDIGITS, PFXOK, and NZDIGITS
 */
#define SIGNOK      0x00040 /* +/- is (still) legal */
#define NDIGITS     0x00080 /* no digits detected */
#define PFXOK       0x00100 /* 0x prefix is (still) legal */
#define NZDIGITS    0x00200 /* no zero digits detected */
#define HAVESIGN    0x10000 /* sign detected */

/*
 * Conversion types.
 */
#define CT_CHAR     0 /* %c conversion */
#define CT_CCL      1 /* %[...] conversion */
#define CT_STRING   2 /* %s conversion */
#define CT_INT      3 /* %[dioupxX] conversion */
#define CT_FLOAT    4 /* %[efgEFG] conversion */

static const u_char  *__sccl(char *, const u_char *);
#ifndef NO_FLOATING_POINT
  static int            parsefloat(FILE *, char *, char *);
#endif

int __scanfdebug = 0;

#define __collate_load_error /*CONSTCOND*/0
static int
__collate_range_cmp(int c1, int c2)
{
  static char s1[2] = { 0 };
  static char s2[2] = { 0 };

  s1[0] = (char)c1;
  s2[0] = (char)c2;
  return strcoll(s1, s2);
}


/*
 * __svfscanf - MT-safe version
 */
int
__svfscanf(FILE *fp, char const *fmt0, va_list ap)
{
  int ret;

  if(fp == NULL) {
    errno = EINVAL;
    return (EOF);
  }
  FLOCKFILE(fp);
  ret = __svfscanf_unlocked(fp, fmt0, ap);
  FUNLOCKFILE(fp);
  return (ret);
}

/*
 * __svfscanf_unlocked - non-MT-safe version of __svfscanf
 */
int
__svfscanf_unlocked(FILE *fp, const char *fmt0, va_list ap)
{
          const u_char     *fmt     = (const u_char *)fmt0;
                int         c;              /* character from format, or conversion */
                size_t      width;          /* field width, or 0 */
                char       *p;              /* points into all kinds of strings */
                size_t      n;              /* handy size_t */
                int         flags;          /* flags as defined above */
                char       *p0;             /* saves original value of p when necessary */
                int         nassigned;      /* number of fields assigned */
                int         nconversions;   /* number of conversions */
                int         nread;          /* number of characters consumed from fp */
                int         base;           /* base argument to conversion function */
                char        ccltab[256];    /* character class table for %[...] */
                char        buf[BUF];       /* buffer for numeric and mb conversions */
                wchar_t    *wcp;            /* handy wide character pointer */
                size_t      nconv;          /* length of multibyte sequence converted */
  static const  mbstate_t   initial = { 0 };
                mbstate_t   mbs;

  /* `basefix' is used to avoid `if' tests in the integer scanner */
  static const short basefix[17] =
    { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };

  _DIAGASSERT(fp != NULL);
  _DIAGASSERT(fmt0 != NULL);
  if(fp == NULL) {
    errno = EINVAL;
    return (EOF);
  }

  _SET_ORIENTATION(fp, -1);

//Print(L"%a( %d, \"%a\", ...)\n", __func__, fp->_file, fmt0);
  nassigned = 0;
  nconversions = 0;
  nread = 0;
  base = 0;
  for (;;) {
    c = (unsigned char)*fmt++;
    if (c == 0)
      return (nassigned);
    if (isspace(c)) {
      while ((fp->_r > 0 || __srefill(fp) == 0) &&
          isspace(*fp->_p))
        nread++, fp->_r--, fp->_p++;
      continue;
    }
//Print(L"%a: %d\n", __func__, __LINE__);
    if (c != '%')
      goto literal;
    width = 0;
    flags = 0;
    /*
     * switch on the format.  continue if done;
     * break once format type is derived.
     */
again:    c = *fmt++;
//Print(L"%a: %d\n", __func__, __LINE__);
    switch (c) {
    case '%':
literal:
//Print(L"%a: %d\n", __func__, __LINE__);
      if (fp->_r <= 0 && __srefill(fp))
        goto input_failure;
      if (*fp->_p != c)
        goto match_failure;
      fp->_r--, fp->_p++;
      nread++;
      continue;

    case '*':
      flags |= SUPPRESS;
      goto again;
    case 'j':
      flags |= INTMAXT;
      goto again;
    case 'l':
      if (flags & LONG) {
        flags &= ~LONG;
        flags |= LONGLONG;
      } else
        flags |= LONG;
      goto again;
    case 'q':
      flags |= LONGLONG;  /* not quite */
      goto again;
    case 't':
      flags |= PTRDIFFT;
      goto again;
    case 'z':
      flags |= SIZET;
      goto again;
    case 'L':
      flags |= LONGDBL;
      goto again;
    case 'h':
      if (flags & SHORT) {
        flags &= ~SHORT;
        flags |= SHORTSHORT;
      } else
        flags |= SHORT;
      goto again;

    case '0': case '1': case '2': case '3': case '4':
    case '5': case '6': case '7': case '8': case '9':
      width = width * 10 + c - '0';
      goto again;

    /*
     * Conversions.
     */
    case 'd':
      c = CT_INT;
      base = 10;
      break;

    case 'i':
      c = CT_INT;
      base = 0;
      break;

    case 'o':
      c = CT_INT;
      flags |= UNSIGNED;
      base = 8;
      break;

    case 'u':
      c = CT_INT;
      flags |= UNSIGNED;
      base = 10;
      break;

    case 'X':
    case 'x':
      flags |= PFXOK; /* enable 0x prefixing */
      c = CT_INT;
      flags |= UNSIGNED;
      base = 16;
      break;

#ifndef NO_FLOATING_POINT
    case 'A': case 'E': case 'F': case 'G':
    case 'a': case 'e': case 'f': case 'g':
      c = CT_FLOAT;
      break;
#endif

    case 'S':
      flags |= LONG;
      /* FALLTHROUGH */
    case 's':
      c = CT_STRING;
      break;

    case '[':
      fmt = __sccl(ccltab, fmt);
      flags |= NOSKIP;
      c = CT_CCL;
      break;

    case 'C':
      flags |= LONG;
      /* FALLTHROUGH */
    case 'c':
      flags |= NOSKIP;
      c = CT_CHAR;
      break;

    case 'p': /* pointer format is like hex */
      flags |= POINTER | PFXOK;
      c = CT_INT;   /* assumes sizeof(uintmax_t) */
      flags |= UNSIGNED;  /*      >= sizeof(uintptr_t) */
      base = 16;
      break;

    case 'n':
      nconversions++;
      if (flags & SUPPRESS) /* ??? */
        continue;
      if (flags & SHORTSHORT)
        *va_arg(ap, char *) = (char)nread;
      else if (flags & SHORT)
        *va_arg(ap, short *) = (short)nread;
      else if (flags & LONG)
        *va_arg(ap, long *) = nread;
      else if (flags & LONGLONG)
        *va_arg(ap, long long *) = nread;
      else if (flags & INTMAXT)
        *va_arg(ap, intmax_t *) = nread;
      else if (flags & SIZET)
        *va_arg(ap, size_t *) = nread;
      else if (flags & PTRDIFFT)
        *va_arg(ap, ptrdiff_t *) = nread;
      else
        *va_arg(ap, int *) = nread;
      continue;

    default:
      goto match_failure;

    /*
     * Disgusting backwards compatibility hack. XXX
     */
    case '\0':  /* compat */
      return (EOF);
    }
//Print(L"%a: %d\n", __func__, __LINE__);

    /*
     * We have a conversion that requires input.
     */
    if (fp->_r <= 0 && __srefill(fp))
    {
//Print(L"%a: %d\n", __func__, __LINE__);
      goto input_failure;
    }

    /*
     * Consume leading white space, except for formats
     * that suppress this.
     */
    if ((flags & NOSKIP) == 0) {
      while (isspace(*fp->_p)) {
        nread++;
        if (--fp->_r > 0)
          fp->_p++;
        else if (__srefill(fp))
        {
//Print(L"%a: %d\n", __func__, __LINE__);
          goto input_failure;
        }
      }
      /*
       * Note that there is at least one character in
       * the buffer, so conversions that do not set NOSKIP
       * ca no longer result in an input failure.
       */
    }

    /*
     * Do the conversion.
     */
//Print(L"%a: %d\n", __func__, __LINE__);
    switch (c) {

    case CT_CHAR:
      /* scan arbitrary characters (sets NOSKIP) */
      if (width == 0)
        width = 1;
      if (flags & LONG) {
        if ((flags & SUPPRESS) == 0)
          wcp = va_arg(ap, wchar_t *);
        else
          wcp = NULL;
        n = 0;
        while (width != 0) {
          if (n == MB_CUR_MAX) {
            fp->_flags |= __SERR;
            goto input_failure;
          }
          buf[n++] = *fp->_p;
          fp->_p++;
          fp->_r--;
          mbs = initial;
          nconv = mbrtowc(wcp, buf, n, &mbs);
          if (nconv == (size_t)-1) {
            fp->_flags |= __SERR;
            goto input_failure;
          }
          if (nconv == 0 && !(flags & SUPPRESS))
            *wcp = L'\0';
          if (nconv != (size_t)-2) {
            nread += (int)n;
            width--;
            if (!(flags & SUPPRESS))
              wcp++;
            n = 0;
          }
          if (fp->_r <= 0 && __srefill(fp)) {
            if (n != 0) {
              fp->_flags |= __SERR;
              goto input_failure;
            }
            break;
          }
        }
        if (!(flags & SUPPRESS))
          nassigned++;
      } else if (flags & SUPPRESS) {
        size_t sum = 0;
        for (;;) {
          if ((n = fp->_r) < width) {
            sum += n;
            width -= n;
            fp->_p += n;
            if (__srefill(fp)) {
              if (sum == 0)
                  goto input_failure;
              break;
            }
          } else {
            sum += width;
            fp->_r -= (int)width;
            fp->_p += width;
            break;
          }
        }
        nread += (int)sum;
      } else {
        size_t r = fread(va_arg(ap, char *), 1,
            width, fp);

        if (r == 0)
          goto input_failure;
        nread += (int)r;
        nassigned++;
      }
      nconversions++;
      break;

    case CT_CCL:
      /* scan a (nonempty) character class (sets NOSKIP) */
      if (width == 0)
        width = (size_t)~0; /* `infinity' */
      /* take only those things in the class */
      if (flags & LONG) {
        wchar_t twc;
        int nchars;

        if ((flags & SUPPRESS) == 0)
          wcp = va_arg(ap, wchar_t *);
        else
          wcp = &twc;
        n = 0;
        nchars = 0;
        while (width != 0) {
          if (n == MB_CUR_MAX) {
            fp->_flags |= __SERR;
            goto input_failure;
          }
          buf[n++] = *fp->_p;
          fp->_p++;
          fp->_r--;
          mbs = initial;
          nconv = mbrtowc(wcp, buf, n, &mbs);
          if (nconv == (size_t)-1) {
            fp->_flags |= __SERR;
            goto input_failure;
          }
          if (nconv == 0)
            *wcp = L'\0';
          if (nconv != (size_t)-2) {
            if (wctob(*wcp) != EOF &&
                !ccltab[wctob(*wcp)]) {
              while (n != 0) {
                n--;
                (void)ungetc(buf[n],
                    fp);
              }
              break;
            }
            nread += (int)n;
            width--;
            if (!(flags & SUPPRESS))
              wcp++;
            nchars++;
            n = 0;
          }
          if (fp->_r <= 0 && __srefill(fp)) {
            if (n != 0) {
              fp->_flags |= __SERR;
              goto input_failure;
            }
            break;
          }
        }
        if (n != 0) {
          fp->_flags |= __SERR;
          goto input_failure;
        }
        n = nchars;
        if (n == 0)
          goto match_failure;
        if (!(flags & SUPPRESS)) {
          *wcp = L'\0';
          nassigned++;
        }
      } else if (flags & SUPPRESS) {
        n = 0;
        while (ccltab[*fp->_p]) {
          n++, fp->_r--, fp->_p++;
          if (--width == 0)
            break;
          if (fp->_r <= 0 && __srefill(fp)) {
            if (n == 0)
              goto input_failure;
            break;
          }
        }
        if (n == 0)
          goto match_failure;
      } else {
        p0 = p = va_arg(ap, char *);
        while (ccltab[*fp->_p]) {
          fp->_r--;
          *p++ = *fp->_p++;
          if (--width == 0)
            break;
          if (fp->_r <= 0 && __srefill(fp)) {
            if (p == p0)
              goto input_failure;
            break;
          }
        }
        n = p - p0;
        if (n == 0)
          goto match_failure;
        *p = 0;
        nassigned++;
      }
      nread += (int)n;
      nconversions++;
      break;

    case CT_STRING:
      /* like CCL, but zero-length string OK, & no NOSKIP */
      if (width == 0)
        width = (size_t)~0;
      if (flags & LONG) {
        wchar_t twc;

        if ((flags & SUPPRESS) == 0)
          wcp = va_arg(ap, wchar_t *);
        else
          wcp = &twc;
        n = 0;
        while (!isspace(*fp->_p) && width != 0) {
          if (n == MB_CUR_MAX) {
            fp->_flags |= __SERR;
            goto input_failure;
          }
          buf[n++] = *fp->_p;
          fp->_p++;
          fp->_r--;
          mbs = initial;
          nconv = mbrtowc(wcp, buf, n, &mbs);
          if (nconv == (size_t)-1) {
            fp->_flags |= __SERR;
            goto input_failure;
          }
          if (nconv == 0)
            *wcp = L'\0';
          if (nconv != (size_t)-2) {
            if (iswspace(*wcp)) {
              while (n != 0) {
                n--;
                (void)ungetc(buf[n],
                    fp);
              }
              break;
            }
            nread += (int)n;
            width--;
            if (!(flags & SUPPRESS))
              wcp++;
            n = 0;
          }
          if (fp->_r <= 0 && __srefill(fp)) {
            if (n != 0) {
              fp->_flags |= __SERR;
              goto input_failure;
            }
            break;
          }
        }
        if (!(flags & SUPPRESS)) {
          *wcp = L'\0';
          nassigned++;
        }
      } else if (flags & SUPPRESS) {
        n = 0;
        while (!isspace(*fp->_p)) {
          n++, fp->_r--, fp->_p++;
          if (--width == 0)
            break;
          if (fp->_r <= 0 && __srefill(fp))
            break;
        }
        nread += (int)n;
      } else {
        p0 = p = va_arg(ap, char *);
        while (!isspace(*fp->_p)) {
          fp->_r--;
          *p++ = *fp->_p++;
          if (--width == 0)
            break;
          if (fp->_r <= 0 && __srefill(fp))
            break;
        }
        *p = 0;
        nread += (int)(p - p0);
        nassigned++;
      }
      nconversions++;
      continue;

    case CT_INT:
//Print(L"%a: %d\n", __func__, __LINE__);
      /* scan an integer as if by the conversion function */
#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
      flags |= SIGNOK | NDIGITS | NZDIGITS;
      for (p = buf; width; width--) {
        c = *fp->_p;
        /*
         * Switch on the character; `goto ok'
         * if we accept it as a part of number.
         */
        switch (c) {

        /*
         * The digit 0 is always legal, but is
         * special.  For %i conversions, if no
         * digits (zero or nonzero) have been
         * scanned (only signs), we will have
         * base==0.  In that case, we should set
         * it to 8 and enable 0x prefixing.
         * Also, if we have not scanned zero digits
         * before this, do not turn off prefixing
         * (someone else will turn it off if we
         * have scanned any nonzero digits).
         */
        case '0':
          if (base == 0) {
            base = 8;
            flags |= PFXOK;
          }
          if (flags & NZDIGITS)
              flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
          else
              flags &= ~(SIGNOK|PFXOK|NDIGITS);
          goto ok;

        /* 1 through 7 always legal */
        case '1': case '2': case '3':
        case '4': case '5': case '6': case '7':
          base = basefix[base];
          flags &= ~(SIGNOK | PFXOK | NDIGITS);
          goto ok;

        /* digits 8 and 9 ok iff decimal or hex */
        case '8': case '9':
          base = basefix[base];
          if (base <= 8)
            break;  /* not legal here */
          flags &= ~(SIGNOK | PFXOK | NDIGITS);
          goto ok;

        /* letters ok iff hex */
        case 'A': case 'B': case 'C':
        case 'D': case 'E': case 'F':
        case 'a': case 'b': case 'c':
        case 'd': case 'e': 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;
            flags |= HAVESIGN;
            goto ok;
          }
          break;

        /*
         * x ok iff flag still set & 2nd char (or
         * 3rd char if we have a sign).
         */
        case 'x': case 'X':
          if (flags & PFXOK && p ==
              buf + 1 + !!(flags & HAVESIGN)) {
            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++ = (char)c;
        if (--fp->_r > 0)
          fp->_p++;
        else if (__srefill(fp))
          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)
          (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) {
        //uintmax_t res;
        // Use a union to get around the truncation warnings.
        union {
          uintmax_t   umax;
          intmax_t    imax;
          void       *vp;
          ptrdiff_t   pdt;
          size_t      sz;
          long long   ll;
          long        lo;
          int         in;
          short       hw;
          char        ch;
        } res;

        *p = 0;
        if ((flags & UNSIGNED) == 0)
            res.imax = strtoimax(buf, (char **)NULL, base);
        else
            res.umax = strtoumax(buf, (char **)NULL, base);
        if (flags & POINTER)
          *va_arg(ap, void **) = res.vp;
              //(void *)((uintptr_t)res);
        else if (flags & SHORTSHORT)
          *va_arg(ap, char *) = res.ch;
        else if (flags & SHORT)
          *va_arg(ap, short *) = res.hw;
        else if (flags & LONG)
          *va_arg(ap, long *) = res.lo;
        else if (flags & LONGLONG)
          *va_arg(ap, long long *) = res.ll;
        else if (flags & INTMAXT)
          *va_arg(ap, intmax_t *) = res.imax;
        else if (flags & PTRDIFFT)
          *va_arg(ap, ptrdiff_t *) = res.pdt;
              //(ptrdiff_t)res;
        else if (flags & SIZET)
          *va_arg(ap, size_t *) = res.sz;
        else
          *va_arg(ap, int *) = res.in;
        nassigned++;
      }
      nread += (int)(p - buf);
      nconversions++;
//Print(L"%a: %d\n", __func__, __LINE__);
      break;

#ifndef NO_FLOATING_POINT
    case CT_FLOAT:
      /* scan a floating point number as if by strtod */
      if (width == 0 || width > sizeof(buf) - 1)
        width = sizeof(buf) - 1;
      if ((width = parsefloat(fp, buf, buf + width)) == 0)
        goto match_failure;
      if ((flags & SUPPRESS) == 0) {
        if (flags & LONGDBL) {
          long double res = strtold(buf, &p);
          *va_arg(ap, long double *) = res;
        } else if (flags & LONG) {
          double res = strtod(buf, &p);
          *va_arg(ap, double *) = res;
        } else {
          float res = strtof(buf, &p);
          *va_arg(ap, float *) = res;
        }
        if (__scanfdebug && p - buf != (ptrdiff_t)width)
          abort();
        nassigned++;
      }
      nread += (int)width;
      nconversions++;
      break;
#endif /* !NO_FLOATING_POINT */
    }
  }
input_failure:
//Print(L"%a: %d\n", __func__, __LINE__);
  return (nconversions != 0 ? nassigned : EOF);
match_failure:
  return (nassigned);
}

/*
 * 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 const u_char *
__sccl(char *tab, const u_char *fmt)
{
  int c, n, v, i;

  _DIAGASSERT(tab != NULL);
  _DIAGASSERT(fmt != NULL);
  /* 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 */

  /* XXX: Will not work if sizeof(tab*) > sizeof(char) */
  (void)memset(tab, v, 256);

  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] = (char)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 == ']' || (__collate_load_error ? n < c :
          __collate_range_cmp(n, c) < 0)) {
        c = '-';
        break;  /* resume the for(;;) */
      }
      fmt++;
      /* fill in the range */
      if (__collate_load_error) {
        do
          tab[++c] = (char)v;
        while (c < n);
      } else {
        for (i = 0; i < 256; i ++)
          if (__collate_range_cmp(c, i) < 0 &&
              __collate_range_cmp(i, n) <= 0)
            tab[i] = (char)v;
      }
#if 1 /* XXX another disgusting compatibility hack */
      c = n;
      /*
       * 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

    case ']':   /* end of scanset */
      return (fmt);

    default:    /* just another character */
      c = n;
      break;
    }
  }
  /* NOTREACHED */
}

#ifndef NO_FLOATING_POINT
static int
parsefloat(FILE *fp, char *buf, char *end)
{
  char *commit, *p;
  int infnanpos = 0;
  enum {
    S_START, S_GOTSIGN, S_INF, S_NAN, S_MAYBEHEX,
    S_DIGITS, S_FRAC, S_EXP, S_EXPDIGITS
  } state = S_START;
  unsigned char c;
  char decpt = *localeconv()->decimal_point;
  _Bool gotmantdig = 0, ishex = 0;

  if(fp == NULL) {
    errno = EINVAL;
    return (EOF);
  }

  /*
   * We set commit = p whenever the string we have read so far
   * constitutes a valid representation of a floating point
   * number by itself.  At some point, the parse will complete
   * or fail, and we will ungetc() back to the last commit point.
   * To ensure that the file offset gets updated properly, it is
   * always necessary to read at least one character that doesn't
   * match; thus, we can't short-circuit "infinity" or "nan(...)".
   */
  commit = buf - 1;
  for (p = buf; p < end; ) {
    c = *fp->_p;
reswitch:
    switch (state) {
    case S_START:
      state = S_GOTSIGN;
      if (c == '-' || c == '+')
        break;
      else
        goto reswitch;
    case S_GOTSIGN:
      switch (c) {
      case '0':
        state = S_MAYBEHEX;
        commit = p;
        break;
      case 'I':
      case 'i':
        state = S_INF;
        break;
      case 'N':
      case 'n':
        state = S_NAN;
        break;
      default:
        state = S_DIGITS;
        goto reswitch;
      }
      break;
    case S_INF:
      if (infnanpos > 6 ||
          (c != "nfinity"[infnanpos] &&
           c != "NFINITY"[infnanpos]))
        goto parsedone;
      if (infnanpos == 1 || infnanpos == 6)
        commit = p; /* inf or infinity */
      infnanpos++;
      break;
    case S_NAN:
      switch (infnanpos) {
      case -1:  /* XXX kludge to deal with nan(...) */
        goto parsedone;
      case 0:
        if (c != 'A' && c != 'a')
          goto parsedone;
        break;
      case 1:
        if (c != 'N' && c != 'n')
          goto parsedone;
        else
          commit = p;
        break;
      case 2:
        if (c != '(')
          goto parsedone;
        break;
      default:
        if (c == ')') {
          commit = p;
          infnanpos = -2;
        } else if (!isalnum(c) && c != '_')
          goto parsedone;
        break;
      }
      infnanpos++;
      break;
    case S_MAYBEHEX:
      state = S_DIGITS;
      if (c == 'X' || c == 'x') {
        ishex = 1;
        break;
      } else {  /* we saw a '0', but no 'x' */
        gotmantdig = 1;
        goto reswitch;
      }
    case S_DIGITS:
      if ((ishex && isxdigit(c)) || isdigit(c))
        gotmantdig = 1;
      else {
        state = S_FRAC;
        if (c != decpt)
          goto reswitch;
      }
      if (gotmantdig)
        commit = p;
      break;
    case S_FRAC:
      if (((c == 'E' || c == 'e') && !ishex) ||
          ((c == 'P' || c == 'p') && ishex)) {
        if (!gotmantdig)
          goto parsedone;
        else
          state = S_EXP;
      } else if ((ishex && isxdigit(c)) || isdigit(c)) {
        commit = p;
        gotmantdig = 1;
      } else
        goto parsedone;
      break;
    case S_EXP:
      state = S_EXPDIGITS;
      if (c == '-' || c == '+')
        break;
      else
        goto reswitch;
    case S_EXPDIGITS:
      if (isdigit(c))
        commit = p;
      else
        goto parsedone;
      break;
    default:
      abort();
    }
    *p++ = c;
    if (--fp->_r > 0)
      fp->_p++;
    else if (__srefill(fp))
      break;  /* EOF */
  }

parsedone:
  while (commit < --p)
    (void)ungetc(*(u_char *)p, fp);
  *++commit = '\0';
  return (int)(commit - buf);
}
#endif