794 lines
18 KiB
C
794 lines
18 KiB
C
/*-
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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. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. 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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* $Id: subr_scanf.c,v 1.4 1999/01/29 08:09:32 dillon Exp $
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* From: Id: vfscanf.c,v 1.13 1998/09/25 12:20:27 obrien Exp
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*/
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/kernel.h>
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#include <machine/limits.h>
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/*
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* Note that stdarg.h and the ANSI style va_start macro is used for both
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* ANSI and traditional C compilers.
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*/
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#include <machine/stdarg.h>
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#define BUF 32 /* 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 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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#define QUAD 0x400
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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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#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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#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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* 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., strtoq or strtouq */
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typedef u_quad_t (*ccfntype)(const char *, const char **, int);
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#define isspace(c) ((c) == ' ' || (c) == '\t' || \
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(c) == '\r' || (c) == '\n')
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#define isascii(c) (((c) & ~0x7f) == 0)
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#define isupper(c) ((c) >= 'A' && (c) <= 'Z')
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#define islower(c) ((c) >= 'a' && (c) <= 'z')
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#define isalpha(c) (isupper(c) || (islower(c)))
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#define isdigit(c) ((c) >= '0' && (c) <= '9')
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static const u_char *__sccl(char *, const u_char *);
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int
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sscanf(const char *ibuf, const char *fmt, ...)
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{
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va_list ap;
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int ret;
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va_start(ap, fmt);
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ret = vsscanf(ibuf, fmt, ap);
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va_end(ap);
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return(ret);
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}
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int
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vsscanf(const char *inp, char const *fmt0, va_list ap)
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{
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int inr;
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const u_char *fmt = (const 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 nconversions; /* number of conversions */
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int nread; /* number of characters consumed from fp */
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int base; /* base argument to strtoq/strtouq */
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ccfntype ccfn; /* conversion function (strtoq/strtouq) */
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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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inr = strlen(inp);
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nassigned = 0;
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nconversions = 0;
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nread = 0;
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base = 0; /* XXX just to keep gcc happy */
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ccfn = NULL; /* 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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while (inr > 0 && isspace(*inp))
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nread++, inr--, inp++;
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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 (inr <= 0)
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goto input_failure;
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if (*inp != c)
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goto match_failure;
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inr--, inp++;
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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 'q':
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flags |= QUAD;
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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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*
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*/
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case 'd':
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c = CT_INT;
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ccfn = (ccfntype)strtoq;
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base = 10;
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break;
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case 'i':
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c = CT_INT;
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ccfn = (ccfntype)strtoq;
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base = 0;
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break;
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case 'o':
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c = CT_INT;
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ccfn = strtouq;
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base = 8;
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break;
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case 'u':
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c = CT_INT;
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ccfn = strtouq;
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base = 10;
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break;
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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 = strtouq;
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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 = strtouq;
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base = 16;
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break;
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case 'n':
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nconversions++;
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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 if (flags & QUAD)
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*va_arg(ap, quad_t *) = 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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/*
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* We have a conversion that requires input.
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*/
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if (inr <= 0)
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goto input_failure;
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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(*inp)) {
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nread++;
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if (--inr > 0)
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inp++;
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else
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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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* can 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 ((n = inr) < width) {
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sum += n;
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width -= n;
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inp += n;
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if (sum == 0)
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goto input_failure;
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break;
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} else {
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sum += width;
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inr -= width;
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inp += 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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bcopy(inp, va_arg(ap, char *), width);
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inr -= width;
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inp += width;
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nread += width;
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nassigned++;
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}
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nconversions++;
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break;
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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 = (size_t)~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[(unsigned char)*inp]) {
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n++, inr--, inp++;
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if (--width == 0)
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break;
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if (inr <= 0) {
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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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}
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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[(unsigned char)*inp]) {
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inr--;
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*p++ = *inp++;
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if (--width == 0)
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break;
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if (inr <= 0) {
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if (p == p0)
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goto input_failure;
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break;
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}
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}
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n = p - p0;
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if (n == 0)
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goto match_failure;
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*p = 0;
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nassigned++;
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}
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nread += n;
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nconversions++;
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break;
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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 = (size_t)~0;
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if (flags & SUPPRESS) {
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n = 0;
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while (!isspace(*inp)) {
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n++, inr--, inp++;
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if (--width == 0)
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break;
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if (inr <= 0)
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break;
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}
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nread += n;
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} else {
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p0 = p = va_arg(ap, char *);
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while (!isspace(*inp)) {
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inr--;
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*p++ = *inp++;
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if (--width == 0)
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break;
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if (inr <= 0)
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break;
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}
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*p = 0;
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nread += p - p0;
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nassigned++;
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}
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nconversions++;
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continue;
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case CT_INT:
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/* scan an integer as if by strtoq/strtouq */
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#ifdef hardway
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if (width == 0 || width > sizeof(buf) - 1)
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width = sizeof(buf) - 1;
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#else
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/* size_t is unsigned, hence this optimisation */
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if (--width > sizeof(buf) - 2)
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width = sizeof(buf) - 2;
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width++;
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#endif
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flags |= SIGNOK | NDIGITS | NZDIGITS;
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for (p = buf; width; width--) {
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c = *inp;
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/*
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* Switch on the character; `goto ok'
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* if we accept it as a part of number.
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*/
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switch (c) {
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/*
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* The digit 0 is always legal, but is
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* special. For %i conversions, if no
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* digits (zero or nonzero) have been
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* scanned (only signs), we will have
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* base==0. In that case, we should set
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* it to 8 and enable 0x prefixing.
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* Also, if we have not scanned zero digits
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* before this, do not turn off prefixing
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* (someone else will turn it off if we
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* have scanned any nonzero digits).
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*/
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case '0':
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if (base == 0) {
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base = 8;
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flags |= PFXOK;
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}
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if (flags & NZDIGITS)
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flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
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else
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flags &= ~(SIGNOK|PFXOK|NDIGITS);
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goto ok;
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/* 1 through 7 always legal */
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case '1': case '2': case '3':
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case '4': case '5': case '6': case '7':
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base = basefix[base];
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flags &= ~(SIGNOK | PFXOK | NDIGITS);
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goto ok;
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/* digits 8 and 9 ok iff decimal or hex */
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case '8': case '9':
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base = basefix[base];
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if (base <= 8)
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break; /* not legal here */
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flags &= ~(SIGNOK | PFXOK | NDIGITS);
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goto ok;
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/* letters ok iff hex */
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case 'A': case 'B': case 'C':
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case 'D': case 'E': case 'F':
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case 'a': case 'b': case 'c':
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case 'd': case 'e': case 'f':
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/* no need to fix base here */
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if (base <= 10)
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break; /* not legal here */
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flags &= ~(SIGNOK | PFXOK | NDIGITS);
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goto ok;
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/* sign ok only as first character */
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case '+': case '-':
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if (flags & SIGNOK) {
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flags &= ~SIGNOK;
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goto ok;
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}
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break;
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/* x ok iff flag still set & 2nd char */
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case 'x': case 'X':
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if (flags & PFXOK && p == buf + 1) {
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base = 16; /* if %i */
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flags &= ~PFXOK;
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goto ok;
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}
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break;
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}
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/*
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* If we got here, c is not a legal character
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* for a number. Stop accumulating digits.
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*/
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break;
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ok:
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/*
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* c is legal: store it and look at the next.
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*/
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*p++ = c;
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if (--inr > 0)
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inp++;
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else
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break; /* end of input */
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}
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/*
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* If we had only a sign, it is no good; push
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* back the sign. If the number ends in `x',
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* it was [sign] '0' 'x', so push back the x
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* and treat it as [sign] '0'.
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*/
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if (flags & NDIGITS) {
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if (p > buf) {
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inp--;
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inr++;
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}
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goto match_failure;
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}
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c = ((u_char *)p)[-1];
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if (c == 'x' || c == 'X') {
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--p;
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inp--;
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inr++;
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}
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if ((flags & SUPPRESS) == 0) {
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u_quad_t res;
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*p = 0;
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res = (*ccfn)(buf, (const char **)NULL, base);
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if (flags & POINTER)
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*va_arg(ap, void **) =
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(void *)(u_long)res;
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else if (flags & SHORT)
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*va_arg(ap, short *) = res;
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else if (flags & LONG)
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*va_arg(ap, long *) = res;
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else if (flags & QUAD)
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*va_arg(ap, quad_t *) = res;
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else
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*va_arg(ap, int *) = res;
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nassigned++;
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}
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nread += p - buf;
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nconversions++;
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break;
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}
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}
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input_failure:
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return (nconversions != 0 ? nassigned : -1);
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match_failure:
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return (nassigned);
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}
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/*
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* Fill in the given table from the scanset at the given format
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* (just after `['). Return a pointer to the character past the
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* closing `]'. The table has a 1 wherever characters should be
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* considered part of the scanset.
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*/
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static const u_char *
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__sccl(char *tab, const u_char *fmt)
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{
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int c, n, v;
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|
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/* first `clear' the whole table */
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c = *fmt++; /* first char hat => negated scanset */
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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) */
|
|
for (n = 0; n < 256; n++)
|
|
tab[n] = v; /* 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] = 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++;
|
|
/* fill in the range */
|
|
do {
|
|
tab[++c] = v;
|
|
} while (c < n);
|
|
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;
|
|
break;
|
|
|
|
case ']': /* end of scanset */
|
|
return (fmt);
|
|
|
|
default: /* just another character */
|
|
c = n;
|
|
break;
|
|
}
|
|
}
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
/*
|
|
* Convert a string to an unsigned quad integer.
|
|
*
|
|
* Ignores `locale' stuff. Assumes that the upper and lower case
|
|
* alphabets and digits are each contiguous.
|
|
*/
|
|
u_quad_t
|
|
strtouq(const char *nptr, const char **endptr, int base)
|
|
{
|
|
const char *s = nptr;
|
|
u_quad_t acc;
|
|
unsigned char c;
|
|
u_quad_t qbase, cutoff;
|
|
int neg, any, cutlim;
|
|
|
|
/*
|
|
* See strtoq for comments as to the logic used.
|
|
*/
|
|
s = nptr;
|
|
do {
|
|
c = *s++;
|
|
} while (isspace(c));
|
|
if (c == '-') {
|
|
neg = 1;
|
|
c = *s++;
|
|
} else {
|
|
neg = 0;
|
|
if (c == '+')
|
|
c = *s++;
|
|
}
|
|
if ((base == 0 || base == 16) &&
|
|
c == '0' && (*s == 'x' || *s == 'X')) {
|
|
c = s[1];
|
|
s += 2;
|
|
base = 16;
|
|
}
|
|
if (base == 0)
|
|
base = c == '0' ? 8 : 10;
|
|
qbase = (unsigned)base;
|
|
cutoff = (u_quad_t)UQUAD_MAX / qbase;
|
|
cutlim = (u_quad_t)UQUAD_MAX % qbase;
|
|
for (acc = 0, any = 0;; c = *s++) {
|
|
if (!isascii(c))
|
|
break;
|
|
if (isdigit(c))
|
|
c -= '0';
|
|
else if (isalpha(c))
|
|
c -= isupper(c) ? 'A' - 10 : 'a' - 10;
|
|
else
|
|
break;
|
|
if (c >= base)
|
|
break;
|
|
if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
|
|
any = -1;
|
|
else {
|
|
any = 1;
|
|
acc *= qbase;
|
|
acc += c;
|
|
}
|
|
}
|
|
if (any < 0) {
|
|
acc = UQUAD_MAX;
|
|
} else if (neg)
|
|
acc = -acc;
|
|
if (endptr != 0)
|
|
*endptr = (const char *)(any ? s - 1 : nptr);
|
|
return (acc);
|
|
}
|
|
|
|
/*
|
|
* Convert a string to a quad integer.
|
|
*
|
|
* Ignores `locale' stuff. Assumes that the upper and lower case
|
|
* alphabets and digits are each contiguous.
|
|
*/
|
|
quad_t
|
|
strtoq(const char *nptr, const char **endptr, int base)
|
|
{
|
|
const char *s;
|
|
u_quad_t acc;
|
|
unsigned char c;
|
|
u_quad_t qbase, cutoff;
|
|
int neg, any, cutlim;
|
|
|
|
/*
|
|
* Skip white space and pick up leading +/- sign if any.
|
|
* If base is 0, allow 0x for hex and 0 for octal, else
|
|
* assume decimal; if base is already 16, allow 0x.
|
|
*/
|
|
s = nptr;
|
|
do {
|
|
c = *s++;
|
|
} while (isspace(c));
|
|
if (c == '-') {
|
|
neg = 1;
|
|
c = *s++;
|
|
} else {
|
|
neg = 0;
|
|
if (c == '+')
|
|
c = *s++;
|
|
}
|
|
if ((base == 0 || base == 16) &&
|
|
c == '0' && (*s == 'x' || *s == 'X')) {
|
|
c = s[1];
|
|
s += 2;
|
|
base = 16;
|
|
}
|
|
if (base == 0)
|
|
base = c == '0' ? 8 : 10;
|
|
|
|
/*
|
|
* Compute the cutoff value between legal numbers and illegal
|
|
* numbers. That is the largest legal value, divided by the
|
|
* base. An input number that is greater than this value, if
|
|
* followed by a legal input character, is too big. One that
|
|
* is equal to this value may be valid or not; the limit
|
|
* between valid and invalid numbers is then based on the last
|
|
* digit. For instance, if the range for quads is
|
|
* [-9223372036854775808..9223372036854775807] and the input base
|
|
* is 10, cutoff will be set to 922337203685477580 and cutlim to
|
|
* either 7 (neg==0) or 8 (neg==1), meaning that if we have
|
|
* accumulated a value > 922337203685477580, or equal but the
|
|
* next digit is > 7 (or 8), the number is too big, and we will
|
|
* return a range error.
|
|
*
|
|
* Set any if any `digits' consumed; make it negative to indicate
|
|
* overflow.
|
|
*/
|
|
qbase = (unsigned)base;
|
|
cutoff = neg ? (u_quad_t)-(QUAD_MIN + QUAD_MAX) + QUAD_MAX : QUAD_MAX;
|
|
cutlim = cutoff % qbase;
|
|
cutoff /= qbase;
|
|
for (acc = 0, any = 0;; c = *s++) {
|
|
if (!isascii(c))
|
|
break;
|
|
if (isdigit(c))
|
|
c -= '0';
|
|
else if (isalpha(c))
|
|
c -= isupper(c) ? 'A' - 10 : 'a' - 10;
|
|
else
|
|
break;
|
|
if (c >= base)
|
|
break;
|
|
if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
|
|
any = -1;
|
|
else {
|
|
any = 1;
|
|
acc *= qbase;
|
|
acc += c;
|
|
}
|
|
}
|
|
if (any < 0) {
|
|
acc = neg ? QUAD_MIN : QUAD_MAX;
|
|
} else if (neg)
|
|
acc = -acc;
|
|
if (endptr != 0)
|
|
*endptr = (const char *)(any ? s - 1 : nptr);
|
|
return (acc);
|
|
}
|