📄 vfscanf.c
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/*- * 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. *//*FUNCTION<<vscanf>>, <<vfscanf>>, <<vsscanf>>---format argument listINDEX vscanfINDEX vfscanfINDEX vsscanfANSI_SYNOPSIS #include <stdio.h> #include <stdarg.h> int vscanf(const char *<[fmt]>, va_list <[list]>); int vfscanf(FILE *<[fp]>, const char *<[fmt]>, va_list <[list]>); int vsscanf(const char *<[str]>, const char *<[fmt]>, va_list <[list]>); int _vscanf_r(struct _reent *<[reent]>, const char *<[fmt]>, va_list <[list]>); int _vfscanf_r(struct _reent *<[reent]>, FILE *<[fp]>, const char *<[fmt]>, va_list <[list]>); int _vsscanf_r(struct _reent *<[reent]>, const char *<[str]>, const char *<[fmt]>, va_list <[list]>);TRAD_SYNOPSIS #include <stdio.h> #include <varargs.h> int vscanf( <[fmt]>, <[ist]>) char *<[fmt]>; va_list <[list]>; int vfscanf( <[fp]>, <[fmt]>, <[list]>) FILE *<[fp]>; char *<[fmt]>; va_list <[list]>; int vsscanf( <[str]>, <[fmt]>, <[list]>) char *<[str]>; char *<[fmt]>; va_list <[list]>; int _vscanf_r( <[reent]>, <[fmt]>, <[ist]>) struct _reent *<[reent]>; char *<[fmt]>; va_list <[list]>; int _vfscanf_r( <[reent]>, <[fp]>, <[fmt]>, <[list]>) struct _reent *<[reent]>; FILE *<[fp]>; char *<[fmt]>; va_list <[list]>; int _vsscanf_r( <[reent]>, <[str]>, <[fmt]>, <[list]>) struct _reent *<[reent]>; char *<[str]>; char *<[fmt]>; va_list <[list]>;DESCRIPTION<<vscanf>>, <<vfscanf>>, and <<vsscanf>> are (respectively) variantsof <<scanf>>, <<fscanf>>, and <<sscanf>>. They differ only in allowing their caller to pass the variable argument list as a <<va_list>> object (initialized by <<va_start>>) rather than directly accepting a variable number of arguments.RETURNSThe return values are consistent with the corresponding functions:<<vscanf>> returns the number of input fields successfully scanned,converted, and stored; the return value does not include scannedfields which were not stored. If <<vscanf>> attempts to read at end-of-file, the return value is <<EOF>>.If no fields were stored, the return value is <<0>>.The routines <<_vscanf_r>>, <<_vfscanf_f>>, and <<_vsscanf_r>> arereentrant versions which take an additional first parameter which points to thereentrancy structure.PORTABILITYThese are GNU extensions.Supporting OS subroutines required:*/#include <_ansi.h>#include <reent.h>#include <newlib.h>#include <ctype.h>#include <wctype.h>#include <stdio.h>#include <stdlib.h>#include <limits.h>#include <wchar.h>#include <string.h>#ifdef _HAVE_STDC#include <stdarg.h>#else#include <varargs.h>#endif#include "local.h"#ifdef INTEGER_ONLY#define VFSCANF vfiscanf#define _VFSCANF_R _vfiscanf_r#define __SVFSCANF __svfiscanf#define __SVFSCANF_R __svfiscanf_r#else#define VFSCANF vfscanf#define _VFSCANF_R _vfscanf_r#define __SVFSCANF __svfscanf#define __SVFSCANF_R __svfscanf_r#ifndef NO_FLOATING_POINT#define FLOATING_POINT#endif#endif#ifdef FLOATING_POINT#include <math.h>#include <float.h>/* Currently a test is made to see if long double processing is warranted. This could be changed in the future should the _ldtoa_r code be preferred over _dtoa_r. */#define _NO_LONGDBL#if defined _WANT_IO_LONG_DOUBLE && (LDBL_MANT_DIG > DBL_MANT_DIG)#undef _NO_LONGDBLextern _LONG_DOUBLE _strtold _PARAMS((char *s, char **sptr));#endif#include "floatio.h"#if ((MAXEXP+MAXFRACT+3) > MB_LEN_MAX)# define BUF (MAXEXP+MAXFRACT+3) /* 3 = sign + decimal point + NUL */#else# define BUF MB_LEN_MAX#endif/* 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#define _NO_LONGLONG#if defined _WANT_IO_LONG_LONG && defined __GNUC__# undef _NO_LONGLONG#endif/* * Flags used during conversion. */#define LONG 0x01 /* l: long or double */#define LONGDBL 0x02 /* L/ll: long double or long long */#define SHORT 0x04 /* h: short */#define CHAR 0x08 /* hh: 8 bit integer */#define SUPPRESS 0x10 /* suppress assignment */#define POINTER 0x20 /* weird %p pointer (`fake hex') */#define NOSKIP 0x40 /* 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 0x80 /* +/- is (still) legal */#define NDIGITS 0x100 /* no digits detected */#define DPTOK 0x200 /* (float) decimal point is still legal */#define EXPOK 0x400 /* (float) exponent (e+3, etc) still legal */#define PFXOK 0x200 /* 0x prefix is (still) legal */#define NZDIGITS 0x400 /* no zero digits detected */#define NNZDIGITS 0x800 /* no non-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#ifndef _NO_LONGLONGtypedef unsigned long long u_long_long;#endif/*static*/ u_char *__sccl ();/* * vfscanf */#define BufferEmpty (fp->_r <= 0 && __srefill_r(rptr, fp))#ifndef _REENT_ONLYint_DEFUN(VFSCANF, (fp, fmt, ap), register FILE *fp _AND _CONST char *fmt _AND va_list ap){ CHECK_INIT(_REENT, fp); return __SVFSCANF_R (_REENT, fp, fmt, ap);}int_DEFUN(__SVFSCANF, (fp, fmt0, ap), register FILE *fp _AND char _CONST *fmt0 _AND va_list ap){ return __SVFSCANF_R (_REENT, fp, fmt0, ap);}#endif /* !_REENT_ONLY */int_DEFUN(_VFSCANF_R, (data, fp, fmt, ap), struct _reent *data _AND register FILE *fp _AND _CONST char *fmt _AND va_list ap){ CHECK_INIT(data, fp); return __SVFSCANF_R (data, fp, fmt, ap);}int_DEFUN(__SVFSCANF_R, (rptr, fp, fmt0, ap), struct _reent *rptr _AND register FILE *fp _AND char _CONST *fmt0 _AND 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 */ wchar_t *wcp; /* handy wide character pointer */ size_t mbslen; /* length of converted multibyte sequence */ mbstate_t state; /* value to keep track of multibyte state */ 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 */ char *cp; short *sp; int *ip; float *flp; _LONG_DOUBLE *ldp; double *dp; long *lp;#ifndef _NO_LONGLONG long long *llp;#endif /* `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}; _flockfile (fp); nassigned = 0; nread = 0; for (;;) {#ifndef _MB_CAPABLE wc = *fmt;#else memset (&state, '\0', sizeof (state)); nbytes = _mbtowc_r (rptr, &wc, fmt, MB_CUR_MAX, &state);#endif fmt += nbytes; if (wc == 0) goto all_done; if (nbytes == 1 && isspace (wc)) { for (;;) { if (BufferEmpty || !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': if (*fmt == 'l') /* Check for 'll' = long long (SUSv3) */ { ++fmt; flags |= LONGDBL; } else flags |= LONG; goto again; case 'L': flags |= LONGDBL; goto again; case 'h': if (*fmt == 'h') /* Check for 'hh' = char int (SUSv3) */ { ++fmt; flags |= CHAR; } 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. 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_r; base = 10; break; case 'i': c = CT_INT; ccfn = (u_long (*)())_strtol_r; base = 0; break; case 'O': /* compat */ flags |= LONG; /* FALLTHROUGH */ case 'o': c = CT_INT; ccfn = _strtoul_r; base = 8; break; case 'u': c = CT_INT; ccfn = _strtoul_r; base = 10; break; case 'X': /* compat XXX */ case 'x': flags |= PFXOK; /* enable 0x prefixing */ c = CT_INT; ccfn = _strtoul_r; 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': 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; ccfn = _strtoul_r; base = 16; break; case 'n': if (flags & SUPPRESS) /* ??? */ continue; if (flags & CHAR) { cp = va_arg (ap, char *); *cp = nread; } else if (flags & SHORT) { sp = va_arg (ap, short *); *sp = nread; } else if (flags & LONG) { lp = va_arg (ap, long *); *lp = nread; }#ifndef _NO_LONGLONG else if (flags & LONGDBL) { llp = va_arg (ap, long long*); *llp = nread; }#endif else { ip = va_arg (ap, int *); *ip = nread; } continue; /* * Disgusting backwards compatibility hacks. XXX */ case '\0': /* compat */ _funlockfile (fp); return EOF; default: /* compat */ if (isupper (c)) flags |= LONG; c = CT_INT; ccfn = (u_long (*)())_strtol_r; 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 if (__srefill_r (rptr, fp)) 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 & LONG) { if ((flags & SUPPRESS) == 0) wcp = va_arg (ap, wchar_t *); else wcp = NULL; n = 0; while (width != 0) { if (n == MB_CUR_MAX) goto input_failure; buf[n++] = *fp->_p; fp->_r -= 1; fp->_p += 1; memset ((_PTR)&state, '\0', sizeof (mbstate_t)); if ((mbslen = _mbrtowc_r (rptr, wcp, buf, n, &state)) == (size_t)-1) goto input_failure; /* Invalid sequence */ if (mbslen == 0 && !(flags & SUPPRESS)) *wcp = L'\0'; if (mbslen != (size_t)-2) /* Incomplete sequence */ { nread += n; width -= 1; if (!(flags & SUPPRESS)) wcp += 1; n = 0; } if (BufferEmpty) { if (n != 0) goto input_failure; break; } } if (!(flags & SUPPRESS)) nassigned++; } else if (flags & SUPPRESS) { size_t sum = 0; for (;;) { if ((n = fp->_r) < (int)width) { sum += n; width -= n; fp->_p += n;
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