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Diffstat (limited to 'newlib/libc/stdio/vfscanf.c')
-rw-r--r--newlib/libc/stdio/vfscanf.c956
1 files changed, 956 insertions, 0 deletions
diff --git a/newlib/libc/stdio/vfscanf.c b/newlib/libc/stdio/vfscanf.c
new file mode 100644
index 0000000..00fd98d
--- /dev/null
+++ b/newlib/libc/stdio/vfscanf.c
@@ -0,0 +1,956 @@
+/* No user fns here. Pesch 15apr92. */
+
+/*
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by the University of California, Berkeley. The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#include <_ansi.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <limits.h>
+#ifdef _HAVE_STDC
+#include <stdarg.h>
+#else
+#include <varargs.h>
+#endif
+#include "local.h"
+
+#ifndef NO_FLOATING_POINT
+#define FLOATING_POINT
+#endif
+
+#ifdef FLOATING_POINT
+#include "floatio.h"
+#define BUF (MAXEXP+MAXFRACT+3) /* 3 = sign + decimal point + NUL */
+/* An upper bound for how long a long prints in decimal. 4 / 13 approximates
+ log (2). Add one char for roundoff compensation and one for the sign. */
+#define MAX_LONG_LEN ((CHAR_BIT * sizeof (long) - 1) * 4 / 13 + 2)
+#else
+#define BUF 40
+#endif
+
+/*
+ * Flags used during conversion.
+ */
+
+#define LONG 0x01 /* l: long or double */
+#define LONGDBL 0x02 /* L: long double; unimplemented */
+#define SHORT 0x04 /* h: short */
+#define SUPPRESS 0x08 /* suppress assignment */
+#define POINTER 0x10 /* weird %p pointer (`fake hex') */
+#define NOSKIP 0x20 /* do not skip blanks */
+
+/*
+ * The following are used in numeric conversions only:
+ * SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point;
+ * SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral.
+ */
+
+#define SIGNOK 0x40 /* +/- is (still) legal */
+#define NDIGITS 0x80 /* no digits detected */
+
+#define DPTOK 0x100 /* (float) decimal point is still legal */
+#define EXPOK 0x200 /* (float) exponent (e+3, etc) still legal */
+
+#define PFXOK 0x100 /* 0x prefix is (still) legal */
+#define NZDIGITS 0x200 /* no zero digits detected */
+
+/*
+ * Conversion types.
+ */
+
+#define CT_CHAR 0 /* %c conversion */
+#define CT_CCL 1 /* %[...] conversion */
+#define CT_STRING 2 /* %s conversion */
+#define CT_INT 3 /* integer, i.e., strtol or strtoul */
+#define CT_FLOAT 4 /* floating, i.e., strtod */
+
+#if 0
+#define u_char unsigned char
+#endif
+#define u_char char
+#define u_long unsigned long
+
+/*static*/ u_char *__sccl ();
+
+/*
+ * vfscanf
+ */
+
+#define BufferEmpty (fp->_r <= 0 && __srefill(fp))
+
+int
+__svfscanf (fp, fmt0, ap)
+ register FILE *fp;
+ char _CONST *fmt0;
+ va_list ap;
+{
+ register u_char *fmt = (u_char *) fmt0;
+ register int c; /* character from format, or conversion */
+ register size_t width; /* field width, or 0 */
+ register char *p; /* points into all kinds of strings */
+ register int n; /* handy integer */
+ register int flags; /* flags as defined above */
+ register char *p0; /* saves original value of p when necessary */
+ int nassigned; /* number of fields assigned */
+ int nread; /* number of characters consumed from fp */
+ int base = 0; /* base argument to strtol/strtoul */
+ int nbytes = 1; /* number of bytes read from fmt string */
+ wchar_t wc; /* wchar to use to read format string */
+
+ u_long (*ccfn) () = 0; /* conversion function (strtol/strtoul) */
+ char ccltab[256]; /* character class table for %[...] */
+ char buf[BUF]; /* buffer for numeric conversions */
+ char *lptr; /* literal pointer */
+ int state = 0; /* value to keep track of multibyte state */
+
+ short *sp;
+ int *ip;
+ float *flp;
+ _LONG_DOUBLE *ldp;
+ double *dp;
+ long *lp;
+
+ /* `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};
+
+ nassigned = 0;
+ nread = 0;
+ for (;;)
+ {
+#ifndef MB_CAPABLE
+ wc = *fmt;
+#else
+ nbytes = _mbtowc_r (_REENT, &wc, fmt, MB_CUR_MAX, &state);
+#endif
+ fmt += nbytes;
+ if (wc == 0)
+ return nassigned;
+ if (nbytes == 1 && isspace (wc))
+ {
+ for (;;)
+ {
+ if (BufferEmpty)
+ return nassigned;
+ if (!isspace (*fp->_p))
+ break;
+ nread++, fp->_r--, fp->_p++;
+ }
+ continue;
+ }
+ if (wc != '%')
+ goto literal;
+ width = 0;
+ flags = 0;
+
+ /*
+ * switch on the format. continue if done; break once format
+ * type is derived.
+ */
+
+ again:
+ c = *fmt++;
+
+ switch (c)
+ {
+ case '%':
+ literal:
+ lptr = fmt - nbytes;
+ for (n = 0; n < nbytes; ++n)
+ {
+ if (BufferEmpty)
+ goto input_failure;
+ if (*fp->_p != *lptr)
+ goto match_failure;
+ fp->_r--, fp->_p++;
+ nread++;
+ ++lptr;
+ }
+ continue;
+
+ case '*':
+ flags |= SUPPRESS;
+ goto again;
+ case 'l':
+ flags |= LONG;
+ goto again;
+ case 'L':
+ flags |= LONGDBL;
+ goto again;
+ case 'h':
+ 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. Those marked `compat' are for
+ * 4.[123]BSD compatibility.
+ *
+ * (According to ANSI, E and X formats are supposed to
+ * the same as e and x. Sorry about that.)
+ */
+
+ case 'D': /* compat */
+ flags |= LONG;
+ /* FALLTHROUGH */
+ case 'd':
+ c = CT_INT;
+ ccfn = (u_long (*)())strtol;
+ base = 10;
+ break;
+
+ case 'i':
+ c = CT_INT;
+ ccfn = (u_long (*)())strtol;
+ base = 0;
+ break;
+
+ case 'O': /* compat */
+ flags |= LONG;
+ /* FALLTHROUGH */
+ case 'o':
+ c = CT_INT;
+ ccfn = strtoul;
+ base = 8;
+ break;
+
+ case 'u':
+ c = CT_INT;
+ ccfn = strtoul;
+ base = 10;
+ break;
+
+ case 'X': /* compat XXX */
+ case 'x':
+ flags |= PFXOK; /* enable 0x prefixing */
+ c = CT_INT;
+ ccfn = strtoul;
+ base = 16;
+ break;
+
+#ifdef FLOATING_POINT
+ case 'E': /* compat XXX */
+ case 'G': /* compat XXX */
+/* ANSI says that E,G and X behave the same way as e,g,x */
+ /* FALLTHROUGH */
+ case 'e':
+ case 'f':
+ case 'g':
+ c = CT_FLOAT;
+ break;
+#endif
+
+ case 's':
+ c = CT_STRING;
+ break;
+
+ case '[':
+ fmt = __sccl (ccltab, fmt);
+ flags |= NOSKIP;
+ c = CT_CCL;
+ break;
+
+ case 'c':
+ flags |= NOSKIP;
+ c = CT_CHAR;
+ break;
+
+ case 'p': /* pointer format is like hex */
+ flags |= POINTER | PFXOK;
+ c = CT_INT;
+ ccfn = strtoul;
+ base = 16;
+ break;
+
+ case 'n':
+ if (flags & SUPPRESS) /* ??? */
+ continue;
+ if (flags & SHORT)
+ {
+ sp = va_arg (ap, short *);
+ *sp = nread;
+ }
+ else if (flags & LONG)
+ {
+ lp = va_arg (ap, long *);
+ *lp = nread;
+ }
+ else
+ {
+ ip = va_arg (ap, int *);
+ *ip = nread;
+ }
+ continue;
+
+ /*
+ * Disgusting backwards compatibility hacks. XXX
+ */
+ case '\0': /* compat */
+ return EOF;
+
+ default: /* compat */
+ if (isupper (c))
+ flags |= LONG;
+ c = CT_INT;
+ ccfn = (u_long (*)())strtol;
+ base = 10;
+ break;
+ }
+
+ /*
+ * We have a conversion that requires input.
+ */
+ if (BufferEmpty)
+ 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
+#ifndef CYGNUS_NEC
+ if (__srefill (fp))
+#endif
+ 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.
+ */
+ switch (c)
+ {
+
+ case CT_CHAR:
+ /* scan arbitrary characters (sets NOSKIP) */
+ if (width == 0)
+ width = 1;
+ if (flags & SUPPRESS)
+ {
+ size_t sum = 0;
+
+ for (;;)
+ {
+ if ((n = fp->_r) < width)
+ {
+ sum += n;
+ width -= n;
+ fp->_p += n;
+#ifndef CYGNUS_NEC
+ if (__srefill (fp))
+ {
+#endif
+ if (sum == 0)
+ goto input_failure;
+ break;
+#ifndef CYGNUS_NEC
+ }
+#endif
+ }
+ else
+ {
+ sum += width;
+ fp->_r -= width;
+ fp->_p += width;
+ break;
+ }
+ }
+ nread += sum;
+ }
+ else
+ {
+#ifdef CYGNUS_NEC
+ /* Kludge city for the moment */
+ char *dest = va_arg (ap, char *);
+ int n = width;
+ if (fp->_r == 0)
+ goto input_failure;
+
+ while (n && fp->_r)
+ {
+ *dest++ = *(fp->_p++);
+ n--;
+ fp->_r--;
+ nread++;
+ }
+#else
+ size_t r = fread ((_PTR) va_arg (ap, char *), 1, width, fp);
+
+ if (r == 0)
+ goto input_failure;
+ nread += r;
+#endif
+ nassigned++;
+ }
+ break;
+
+ case CT_CCL:
+ /* scan a (nonempty) character class (sets NOSKIP) */
+ if (width == 0)
+ width = ~0; /* `infinity' */
+ /* take only those things in the class */
+ if (flags & SUPPRESS)
+ {
+ n = 0;
+ while (ccltab[*fp->_p])
+ {
+ n++, fp->_r--, fp->_p++;
+ if (--width == 0)
+ break;
+ if (BufferEmpty)
+ {
+ 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 (BufferEmpty)
+ {
+ if (p == p0)
+ goto input_failure;
+ break;
+ }
+ }
+ n = p - p0;
+ if (n == 0)
+ goto match_failure;
+ *p = 0;
+ nassigned++;
+ }
+ nread += n;
+ break;
+
+ case CT_STRING:
+ /* like CCL, but zero-length string OK, & no NOSKIP */
+ if (width == 0)
+ width = ~0;
+ if (flags & SUPPRESS)
+ {
+ n = 0;
+ while (!isspace (*fp->_p))
+ {
+ n++, fp->_r--, fp->_p++;
+ if (--width == 0)
+ break;
+ if (BufferEmpty)
+ break;
+ }
+ nread += n;
+ }
+ else
+ {
+ p0 = p = va_arg (ap, char *);
+ while (!isspace (*fp->_p))
+ {
+ fp->_r--;
+ *p++ = *fp->_p++;
+ if (--width == 0)
+ break;
+ if (BufferEmpty)
+ break;
+ }
+ *p = 0;
+ nread += p - p0;
+ nassigned++;
+ }
+ continue;
+
+ case CT_INT:
+ /* scan an integer as if by strtol/strtoul */
+#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;
+ 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;
+ if (--fp->_r > 0)
+ fp->_p++;
+ else
+#ifndef CYGNUS_NEC
+ if (__srefill (fp))
+#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, _PTR *)) = (_PTR) (unsigned _POINTER_INT) 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;
+
+#ifdef FLOATING_POINT
+ case CT_FLOAT:
+ {
+ /* scan a floating point number as if by strtod */
+ /* This code used to assume that the number of digits is reasonable.
+ However, ANSI / ISO C makes no such stipulation; we have to get
+ exact results even when there is an unreasonable amount of
+ leading zeroes. */
+ long leading_zeroes, zeroes, exp_adjust;
+ char *exp_start;
+#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 | DPTOK | EXPOK;
+ zeroes = 0;
+ exp_adjust = 0;
+ for (p = buf; width; )
+ {
+ c = *fp->_p;
+ /*
+ * This code mimicks the integer conversion
+ * code, but is much simpler.
+ */
+ switch (c)
+ {
+
+ case '0':
+ if (flags & NDIGITS)
+ {
+ flags &= ~SIGNOK;
+ zeroes++;
+ goto fskip;
+ }
+ /* Fall through. */
+ 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);
+ leading_zeroes = zeroes;
+ goto fok;
+ }
+ break;
+ case 'e':
+ case 'E':
+ /* no exponent without some digits */
+ if ((flags & (NDIGITS | EXPOK)) == EXPOK
+ || ((flags & EXPOK) && zeroes))
+ {
+ if (! (flags & DPTOK))
+ {
+ exp_adjust = zeroes - leading_zeroes;
+ exp_start = p;
+ }
+ flags =
+ (flags & ~(EXPOK | DPTOK)) |
+ SIGNOK | NDIGITS;
+ zeroes = 0;
+ goto fok;
+ }
+ break;
+ }
+ break;
+ fok:
+ *p++ = c;
+ width--;
+ fskip:
+ if (--fp->_r > 0)
+ fp->_p++;
+ else
+#ifndef CYGNUS_NEC
+ if (__srefill (fp))
+#endif
+ break; /* EOF */
+ }
+ if (zeroes)
+ flags &= ~NDIGITS;
+ /*
+ * 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;
+ long new_exp;
+
+ *p = 0;
+ if ((flags & (DPTOK | EXPOK)) == EXPOK)
+ {
+ exp_adjust = zeroes - leading_zeroes;
+ new_exp = -exp_adjust;
+ exp_start = p;
+ }
+ else if (exp_adjust)
+ new_exp = atol (exp_start + 1) - exp_adjust;
+ if (exp_adjust)
+ {
+
+ /* If there might not be enough space for the new exponent,
+ truncate some trailing digits to make room. */
+ if (exp_start >= buf + sizeof (buf) - MAX_LONG_LEN)
+ exp_start = buf + sizeof (buf) - MAX_LONG_LEN - 1;
+ sprintf (exp_start, "e%d", new_exp);
+ }
+ res = atof (buf);
+ 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;
+ }
+#endif /* FLOATING_POINT */
+ }
+ }
+input_failure:
+ return nassigned ? nassigned : -1;
+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*/
+u_char *
+__sccl (tab, fmt)
+ register char *tab;
+ register u_char *fmt;
+{
+ register 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 */
+}
generated by cgit v1.1 at 2024-11-15 14:28:13 +0000