scoutos / prex-0.9.0 / usr / lib / libc / stdio / vfscanf.c @ 03e9c04a
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/*-
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* Copyright (c) 1990, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* Chris Torek.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <ctype.h> |
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#include <stdarg.h> |
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#include "local.h" |
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#define BUF 513 /* Maximum length of numeric string. */ |
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/*
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* Flags used during conversion.
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*/
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#define LONG 0x01 /* l: long or double */ |
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#define LONGDBL 0x02 /* L: long double; unimplemented */ |
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#define SHORT 0x04 /* h: short */ |
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#define SUPPRESS 0x08 /* suppress assignment */ |
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#define POINTER 0x10 /* weird %p pointer (`fake hex') */ |
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#define NOSKIP 0x20 /* do not skip blanks */ |
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|
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/*
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* The following are used in numeric conversions only:
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* SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point;
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* SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral.
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*/
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#define SIGNOK 0x40 /* +/- is (still) legal */ |
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#define NDIGITS 0x80 /* no digits detected */ |
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|
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#define DPTOK 0x100 /* (float) decimal point is still legal */ |
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#define EXPOK 0x200 /* (float) exponent (e+3, etc) still legal */ |
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|
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#define PFXOK 0x100 /* 0x prefix is (still) legal */ |
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#define NZDIGITS 0x200 /* no zero digits detected */ |
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|
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/*
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* Conversion types.
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*/
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#define CT_CHAR 0 /* %c conversion */ |
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#define CT_CCL 1 /* %[...] conversion */ |
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#define CT_STRING 2 /* %s conversion */ |
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#define CT_INT 3 /* integer, i.e., strtol or strtoul */ |
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#define CT_FLOAT 4 /* floating, i.e., strtod */ |
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|
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#define u_char unsigned char |
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#define u_long unsigned long |
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|
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static u_char *__sccl(char *, u_char *); |
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|
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/*
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* vfscanf
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*/
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int
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__svfscanf(fp, fmt0, ap) |
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FILE *fp; |
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char const *fmt0; |
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va_list ap; |
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{
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u_char *fmt = (u_char *)fmt0; |
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int c; /* character from format, or conversion */ |
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size_t width; /* field width, or 0 */
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char *p; /* points into all kinds of strings */ |
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int n; /* handy integer */ |
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int flags; /* flags as defined above */ |
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char *p0; /* saves original value of p when necessary */ |
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int nassigned; /* number of fields assigned */ |
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int nread; /* number of characters consumed from fp */ |
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int base; /* base argument to strtol/strtoul */ |
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u_long (*ccfn)(const char *, char **, int); |
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/* conversion function (strtol/strtoul) */
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char ccltab[256]; /* character class table for %[...] */ |
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char buf[BUF]; /* buffer for numeric conversions */ |
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/* `basefix' is used to avoid `if' tests in the integer scanner */
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static short basefix[17] = |
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{ 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
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nassigned = 0;
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nread = 0;
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base = 0; /* XXX just to keep gcc happy */ |
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ccfn = 0; /* XXX just to keep gcc happy */ |
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for (;;) {
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c = *fmt++; |
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if (c == 0) |
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return (nassigned);
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if (isspace(c)) {
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for (;;) {
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if (fp->_r <= 0 && __srefill(fp)) |
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return (nassigned);
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if (!isspace(*fp->_p))
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break;
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nread++, fp->_r--, fp->_p++; |
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} |
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continue;
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} |
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if (c != '%') |
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goto literal;
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width = 0;
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flags = 0;
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/*
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* switch on the format. continue if done;
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* break once format type is derived.
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*/
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again: c = *fmt++;
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switch (c) {
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case '%': |
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literal:
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if (fp->_r <= 0 && __srefill(fp)) |
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goto input_failure;
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if (*fp->_p != c)
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goto match_failure;
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fp->_r--, fp->_p++; |
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nread++; |
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continue;
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case '*': |
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flags |= SUPPRESS; |
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goto again;
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case 'l': |
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flags |= LONG; |
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goto again;
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case 'L': |
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flags |= LONGDBL; |
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goto again;
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case 'h': |
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flags |= SHORT; |
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goto again;
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case '0': case '1': case '2': case '3': case '4': |
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case '5': case '6': case '7': case '8': case '9': |
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width = width * 10 + c - '0'; |
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goto again;
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/*
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* Conversions.
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* Those marked `compat' are for 4.[123]BSD compatibility.
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*
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* (According to ANSI, E and X formats are supposed
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* to the same as e and x. Sorry about that.)
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*/
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case 'D': /* compat */ |
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flags |= LONG; |
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/* FALLTHROUGH */
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case 'd': |
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c = CT_INT; |
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ccfn = (u_long (*)(const char *, char **, int))strtol; |
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base = 10;
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break;
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|
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case 'i': |
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c = CT_INT; |
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ccfn = (u_long (*)(const char *, char **, int))strtol; |
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base = 0;
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break;
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|
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case 'O': /* compat */ |
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flags |= LONG; |
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/* FALLTHROUGH */
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case 'o': |
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c = CT_INT; |
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ccfn = strtoul; |
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base = 8;
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break;
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|
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case 'u': |
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c = CT_INT; |
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ccfn = strtoul; |
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base = 10;
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break;
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case 'X': /* compat XXX */ |
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flags |= LONG; |
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/* FALLTHROUGH */
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case 'x': |
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flags |= PFXOK; /* enable 0x prefixing */
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c = CT_INT; |
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ccfn = strtoul; |
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base = 16;
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break;
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case 's': |
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c = CT_STRING; |
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break;
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case '[': |
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fmt = __sccl(ccltab, fmt); |
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flags |= NOSKIP; |
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c = CT_CCL; |
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break;
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case 'c': |
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flags |= NOSKIP; |
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c = CT_CHAR; |
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break;
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case 'p': /* pointer format is like hex */ |
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flags |= POINTER | PFXOK; |
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c = CT_INT; |
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ccfn = strtoul; |
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base = 16;
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break;
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case 'n': |
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if (flags & SUPPRESS) /* ??? */ |
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continue;
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if (flags & SHORT)
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*va_arg(ap, short *) = nread;
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else if (flags & LONG) |
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*va_arg(ap, long *) = nread;
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else
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*va_arg(ap, int *) = nread;
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continue;
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/*
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* Disgusting backwards compatibility hacks. XXX
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*/
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case '\0': /* compat */ |
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return (EOF); |
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default: /* compat */ |
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if (isupper(c))
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flags |= LONG; |
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c = CT_INT; |
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ccfn = (u_long (*)(const char *, char **, int))strtol; |
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base = 10;
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break;
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} |
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/*
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* We have a conversion that requires input.
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*/
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if (fp->_r <= 0 && __srefill(fp)) |
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goto input_failure;
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|
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/*
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* Consume leading white space, except for formats
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* that suppress this.
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*/
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if ((flags & NOSKIP) == 0) { |
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while (isspace(*fp->_p)) {
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nread++; |
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if (--fp->_r > 0) |
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fp->_p++; |
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else if (__srefill(fp)) |
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goto input_failure;
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} |
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/*
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* Note that there is at least one character in
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* the buffer, so conversions that do not set NOSKIP
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* ca no longer result in an input failure.
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*/
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} |
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/*
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* Do the conversion.
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*/
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switch (c) {
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case CT_CHAR:
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/* scan arbitrary characters (sets NOSKIP) */
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if (width == 0) |
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width = 1;
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if (flags & SUPPRESS) {
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size_t sum = 0;
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for (;;) {
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if ((size_t)(n = fp->_r) < width) {
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sum += n; |
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width -= n; |
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fp->_p += n; |
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if (__srefill(fp)) {
|
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if (sum == 0) |
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goto input_failure;
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break;
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} |
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} else {
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sum += width; |
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fp->_r -= width; |
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fp->_p += width; |
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break;
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} |
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} |
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nread += sum; |
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} else {
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size_t r = fread((void *)va_arg(ap, char *), 1, |
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width, fp); |
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|
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if (r == 0) |
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goto input_failure;
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nread += r; |
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nassigned++; |
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} |
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break;
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|
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case CT_CCL:
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/* scan a (nonempty) character class (sets NOSKIP) */
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if (width == 0) |
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width = ~0; /* `infinity' */ |
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/* take only those things in the class */
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if (flags & SUPPRESS) {
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n = 0;
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while (ccltab[*fp->_p]) {
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n++, fp->_r--, fp->_p++; |
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if (--width == 0) |
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break;
|
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if (fp->_r <= 0 && __srefill(fp)) { |
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if (n == 0) |
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goto input_failure;
|
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break;
|
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} |
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} |
| 340 |
if (n == 0) |
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goto match_failure;
|
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} else {
|
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p0 = p = va_arg(ap, char *);
|
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while (ccltab[*fp->_p]) {
|
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fp->_r--; |
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*p++ = *fp->_p++; |
| 347 |
if (--width == 0) |
| 348 |
break;
|
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if (fp->_r <= 0 && __srefill(fp)) { |
| 350 |
if (p == p0)
|
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goto input_failure;
|
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break;
|
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} |
| 354 |
} |
| 355 |
n = p - p0; |
| 356 |
if (n == 0) |
| 357 |
goto match_failure;
|
| 358 |
*p = 0;
|
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nassigned++; |
| 360 |
} |
| 361 |
nread += n; |
| 362 |
break;
|
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|
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case CT_STRING:
|
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/* like CCL, but zero-length string OK, & no NOSKIP */
|
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if (width == 0) |
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width = ~0;
|
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if (flags & SUPPRESS) {
|
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n = 0;
|
| 370 |
while (!isspace(*fp->_p)) {
|
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n++, fp->_r--, fp->_p++; |
| 372 |
if (--width == 0) |
| 373 |
break;
|
| 374 |
if (fp->_r <= 0 && __srefill(fp)) |
| 375 |
break;
|
| 376 |
} |
| 377 |
nread += n; |
| 378 |
} else {
|
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p0 = p = va_arg(ap, char *);
|
| 380 |
while (!isspace(*fp->_p)) {
|
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fp->_r--; |
| 382 |
*p++ = *fp->_p++; |
| 383 |
if (--width == 0) |
| 384 |
break;
|
| 385 |
if (fp->_r <= 0 && __srefill(fp)) |
| 386 |
break;
|
| 387 |
} |
| 388 |
*p = 0;
|
| 389 |
nread += p - p0; |
| 390 |
nassigned++; |
| 391 |
} |
| 392 |
continue;
|
| 393 |
|
| 394 |
case CT_INT:
|
| 395 |
/* scan an integer as if by strtol/strtoul */
|
| 396 |
#ifdef hardway
|
| 397 |
if (width == 0 || width > sizeof(buf) - 1) |
| 398 |
width = sizeof(buf) - 1; |
| 399 |
#else
|
| 400 |
/* size_t is unsigned, hence this optimisation */
|
| 401 |
if (--width > sizeof(buf) - 2) |
| 402 |
width = sizeof(buf) - 2; |
| 403 |
width++; |
| 404 |
#endif
|
| 405 |
flags |= SIGNOK | NDIGITS | NZDIGITS; |
| 406 |
for (p = buf; width; width--) {
|
| 407 |
c = *fp->_p; |
| 408 |
/*
|
| 409 |
* Switch on the character; `goto ok'
|
| 410 |
* if we accept it as a part of number.
|
| 411 |
*/
|
| 412 |
switch (c) {
|
| 413 |
|
| 414 |
/*
|
| 415 |
* The digit 0 is always legal, but is
|
| 416 |
* special. For %i conversions, if no
|
| 417 |
* digits (zero or nonzero) have been
|
| 418 |
* scanned (only signs), we will have
|
| 419 |
* base==0. In that case, we should set
|
| 420 |
* it to 8 and enable 0x prefixing.
|
| 421 |
* Also, if we have not scanned zero digits
|
| 422 |
* before this, do not turn off prefixing
|
| 423 |
* (someone else will turn it off if we
|
| 424 |
* have scanned any nonzero digits).
|
| 425 |
*/
|
| 426 |
case '0': |
| 427 |
if (base == 0) { |
| 428 |
base = 8;
|
| 429 |
flags |= PFXOK; |
| 430 |
} |
| 431 |
if (flags & NZDIGITS)
|
| 432 |
flags &= ~(SIGNOK|NZDIGITS|NDIGITS); |
| 433 |
else
|
| 434 |
flags &= ~(SIGNOK|PFXOK|NDIGITS); |
| 435 |
goto ok;
|
| 436 |
|
| 437 |
/* 1 through 7 always legal */
|
| 438 |
case '1': case '2': case '3': |
| 439 |
case '4': case '5': case '6': case '7': |
| 440 |
base = basefix[base]; |
| 441 |
flags &= ~(SIGNOK | PFXOK | NDIGITS); |
| 442 |
goto ok;
|
| 443 |
|
| 444 |
/* digits 8 and 9 ok iff decimal or hex */
|
| 445 |
case '8': case '9': |
| 446 |
base = basefix[base]; |
| 447 |
if (base <= 8) |
| 448 |
break; /* not legal here */ |
| 449 |
flags &= ~(SIGNOK | PFXOK | NDIGITS); |
| 450 |
goto ok;
|
| 451 |
|
| 452 |
/* letters ok iff hex */
|
| 453 |
case 'A': case 'B': case 'C': |
| 454 |
case 'D': case 'E': case 'F': |
| 455 |
case 'a': case 'b': case 'c': |
| 456 |
case 'd': case 'e': case 'f': |
| 457 |
/* no need to fix base here */
|
| 458 |
if (base <= 10) |
| 459 |
break; /* not legal here */ |
| 460 |
flags &= ~(SIGNOK | PFXOK | NDIGITS); |
| 461 |
goto ok;
|
| 462 |
|
| 463 |
/* sign ok only as first character */
|
| 464 |
case '+': case '-': |
| 465 |
if (flags & SIGNOK) {
|
| 466 |
flags &= ~SIGNOK; |
| 467 |
goto ok;
|
| 468 |
} |
| 469 |
break;
|
| 470 |
|
| 471 |
/* x ok iff flag still set & 2nd char */
|
| 472 |
case 'x': case 'X': |
| 473 |
if (flags & PFXOK && p == buf + 1) { |
| 474 |
base = 16; /* if %i */ |
| 475 |
flags &= ~PFXOK; |
| 476 |
goto ok;
|
| 477 |
} |
| 478 |
break;
|
| 479 |
} |
| 480 |
|
| 481 |
/*
|
| 482 |
* If we got here, c is not a legal character
|
| 483 |
* for a number. Stop accumulating digits.
|
| 484 |
*/
|
| 485 |
break;
|
| 486 |
ok:
|
| 487 |
/*
|
| 488 |
* c is legal: store it and look at the next.
|
| 489 |
*/
|
| 490 |
*p++ = c; |
| 491 |
if (--fp->_r > 0) |
| 492 |
fp->_p++; |
| 493 |
else if (__srefill(fp)) |
| 494 |
break; /* EOF */ |
| 495 |
} |
| 496 |
/*
|
| 497 |
* If we had only a sign, it is no good; push
|
| 498 |
* back the sign. If the number ends in `x',
|
| 499 |
* it was [sign] '0' 'x', so push back the x
|
| 500 |
* and treat it as [sign] '0'.
|
| 501 |
*/
|
| 502 |
if (flags & NDIGITS) {
|
| 503 |
if (p > buf)
|
| 504 |
(void) ungetc(*(u_char *)--p, fp);
|
| 505 |
goto match_failure;
|
| 506 |
} |
| 507 |
c = ((u_char *)p)[-1];
|
| 508 |
if (c == 'x' || c == 'X') { |
| 509 |
--p; |
| 510 |
(void) ungetc(c, fp);
|
| 511 |
} |
| 512 |
if ((flags & SUPPRESS) == 0) { |
| 513 |
u_long res; |
| 514 |
|
| 515 |
*p = 0;
|
| 516 |
res = (*ccfn)(buf, (char **)NULL, base); |
| 517 |
if (flags & POINTER)
|
| 518 |
*va_arg(ap, void **) = (void *)res; |
| 519 |
else if (flags & SHORT) |
| 520 |
*va_arg(ap, short *) = res;
|
| 521 |
else if (flags & LONG) |
| 522 |
*va_arg(ap, long *) = res;
|
| 523 |
else
|
| 524 |
*va_arg(ap, int *) = res;
|
| 525 |
nassigned++; |
| 526 |
} |
| 527 |
nread += p - buf; |
| 528 |
break;
|
| 529 |
|
| 530 |
} |
| 531 |
} |
| 532 |
input_failure:
|
| 533 |
return (nassigned ? nassigned : -1); |
| 534 |
match_failure:
|
| 535 |
return (nassigned);
|
| 536 |
} |
| 537 |
|
| 538 |
/*
|
| 539 |
* Fill in the given table from the scanset at the given format
|
| 540 |
* (just after `['). Return a pointer to the character past the
|
| 541 |
* closing `]'. The table has a 1 wherever characters should be
|
| 542 |
* considered part of the scanset.
|
| 543 |
*/
|
| 544 |
static u_char *
|
| 545 |
__sccl(tab, fmt) |
| 546 |
char *tab;
|
| 547 |
u_char *fmt; |
| 548 |
{
|
| 549 |
int c, n, v;
|
| 550 |
|
| 551 |
/* first `clear' the whole table */
|
| 552 |
c = *fmt++; /* first char hat => negated scanset */
|
| 553 |
if (c == '^') { |
| 554 |
v = 1; /* default => accept */ |
| 555 |
c = *fmt++; /* get new first char */
|
| 556 |
} else
|
| 557 |
v = 0; /* default => reject */ |
| 558 |
/* should probably use memset here */
|
| 559 |
for (n = 0; n < 256; n++) |
| 560 |
tab[n] = v; |
| 561 |
if (c == 0) |
| 562 |
return (fmt - 1);/* format ended before closing ] */ |
| 563 |
|
| 564 |
/*
|
| 565 |
* Now set the entries corresponding to the actual scanset
|
| 566 |
* to the opposite of the above.
|
| 567 |
*
|
| 568 |
* The first character may be ']' (or '-') without being special;
|
| 569 |
* the last character may be '-'.
|
| 570 |
*/
|
| 571 |
v = 1 - v;
|
| 572 |
for (;;) {
|
| 573 |
tab[c] = v; /* take character c */
|
| 574 |
doswitch:
|
| 575 |
n = *fmt++; /* and examine the next */
|
| 576 |
switch (n) {
|
| 577 |
|
| 578 |
case 0: /* format ended too soon */ |
| 579 |
return (fmt - 1); |
| 580 |
|
| 581 |
case '-': |
| 582 |
/*
|
| 583 |
* A scanset of the form
|
| 584 |
* [01+-]
|
| 585 |
* is defined as `the digit 0, the digit 1,
|
| 586 |
* the character +, the character -', but
|
| 587 |
* the effect of a scanset such as
|
| 588 |
* [a-zA-Z0-9]
|
| 589 |
* is implementation defined. The V7 Unix
|
| 590 |
* scanf treats `a-z' as `the letters a through
|
| 591 |
* z', but treats `a-a' as `the letter a, the
|
| 592 |
* character -, and the letter a'.
|
| 593 |
*
|
| 594 |
* For compatibility, the `-' is not considerd
|
| 595 |
* to define a range if the character following
|
| 596 |
* it is either a close bracket (required by ANSI)
|
| 597 |
* or is not numerically greater than the character
|
| 598 |
* we just stored in the table (c).
|
| 599 |
*/
|
| 600 |
n = *fmt; |
| 601 |
if (n == ']' || n < c) { |
| 602 |
c = '-';
|
| 603 |
break; /* resume the for(;;) */ |
| 604 |
} |
| 605 |
fmt++; |
| 606 |
do { /* fill in the range */ |
| 607 |
tab[++c] = v; |
| 608 |
} while (c < n);
|
| 609 |
#if 1 /* XXX another disgusting compatibility hack */ |
| 610 |
/*
|
| 611 |
* Alas, the V7 Unix scanf also treats formats
|
| 612 |
* such as [a-c-e] as `the letters a through e'.
|
| 613 |
* This too is permitted by the standard....
|
| 614 |
*/
|
| 615 |
goto doswitch;
|
| 616 |
#else
|
| 617 |
c = *fmt++; |
| 618 |
if (c == 0) |
| 619 |
return (fmt - 1); |
| 620 |
if (c == ']') |
| 621 |
return (fmt);
|
| 622 |
#endif
|
| 623 |
break;
|
| 624 |
|
| 625 |
case ']': /* end of scanset */ |
| 626 |
return (fmt);
|
| 627 |
|
| 628 |
default: /* just another character */ |
| 629 |
c = n; |
| 630 |
break;
|
| 631 |
} |
| 632 |
} |
| 633 |
/* NOTREACHED */
|
| 634 |
} |