857 lines
20 KiB
C
857 lines
20 KiB
C
/*
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* Copyright (c) 1990 Regents of the University of California.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms are permitted
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* provided that the above copyright notice and this paragraph are
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* duplicated in all such forms and that any documentation,
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* advertising materials, and other materials related to such
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* distribution and use acknowledge that the software was developed
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* by the University of California, Berkeley. The name of the
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* University may not be used to endorse or promote products derived
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* from this software without specific prior written permission.
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
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* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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*/
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#if defined(LIBC_SCCS) && !defined(lint)
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static char sccsid[] = "%W% (Berkeley) %G%";
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#endif /* LIBC_SCCS and not lint */
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/*
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* Actual printf innards.
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*
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* This code is large and complicated...
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*/
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#include <sys/types.h>
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#include "ioprivate.h"
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#include <string.h>
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#include <stdarg.h>
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/*
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* Define FLOATING_POINT to get floating point.
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*/
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#ifndef NO_FLOATING_POINT
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#define FLOATING_POINT
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#endif
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/* end of configuration stuff */
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/*
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* Helper class and function for `fprintf to unbuffered': creates a
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* temporary buffer. We only work on write-only files; this avoids
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* worries about ungetc buffers and so forth.
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*/
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class help_streambuf : public backupbuf {
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public:
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char *buffer;
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int buf_size;
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streambuf *sb;
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help_streambuf(streambuf *sbuf, char *buf, int n) {
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sb = sbuf; buffer = buf; buf_size = n;
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setp(buffer, buffer+buf_size); }
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~help_streambuf();
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virtual int overflow(int c = EOF);
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};
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int help_streambuf::overflow(int c)
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{
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int used = pptr() - pbase();
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if (used) {
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sb->sputn(pbase(), used);
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pbump(-used);
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}
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if (c == EOF || buf_size == 0)
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return sb->overflow(c);
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return sputc(c);
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}
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help_streambuf::~help_streambuf()
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{
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int used = pptr() - pbase();
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if (used) {
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sb->sputn(pbase(), used);
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pbump(-used);
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}
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}
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int help_vform(streambuf *sb, char const *fmt0, va_list ap)
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{
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char buf[_G_BUFSIZ];
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help_streambuf helper(sb, buf, _G_BUFSIZ);
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return helper.vform(fmt0, ap);
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}
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#ifdef FLOATING_POINT
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#include "floatio.h"
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#define BUF (MAXEXP+MAXFRACT+1) /* + decimal point */
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#define DEFPREC 6
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extern "C" double modf(double, double*);
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#else /* no FLOATING_POINT */
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#define BUF 40
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#endif /* FLOATING_POINT */
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/*
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* Macros for converting digits to letters and vice versa
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*/
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#define to_digit(c) ((c) - '0')
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#define is_digit(c) ((unsigned)to_digit(c) <= 9)
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#define to_char(n) ((n) + '0')
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/*
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* Flags used during conversion.
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*/
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#define LONGINT 0x01 /* long integer */
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#define LONGDBL 0x02 /* long double; unimplemented */
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#define SHORTINT 0x04 /* short integer */
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#define ALT 0x08 /* alternate form */
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#define LADJUST 0x10 /* left adjustment */
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#define ZEROPAD 0x20 /* zero (as opposed to blank) pad */
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#define HEXPREFIX 0x40 /* add 0x or 0X prefix */
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int streambuf::vform(char const *fmt0, _G_va_list ap)
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{
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register const char *fmt; /* format string */
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register int ch; /* character from fmt */
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register int n; /* handy integer (short term usage) */
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register char *cp; /* handy char pointer (short term usage) */
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const char *fmark; /* for remembering a place in fmt */
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register int flags; /* flags as above */
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int ret; /* return value accumulator */
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int width; /* width from format (%8d), or 0 */
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int prec; /* precision from format (%.3d), or -1 */
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char sign; /* sign prefix (' ', '+', '-', or \0) */
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#ifdef FLOATING_POINT
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int softsign; /* temporary negative sign for floats */
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double _double; /* double precision arguments %[eEfgG] */
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#ifndef USE_DTOA
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int fpprec; /* `extra' floating precision in [eEfgG] */
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#endif
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#endif
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unsigned long _ulong; /* integer arguments %[diouxX] */
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enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */
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int dprec; /* a copy of prec if [diouxX], 0 otherwise */
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int dpad; /* extra 0 padding needed for integers */
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int fieldsz; /* field size expanded by sign, dpad etc */
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// The initialization of 'size' is to suppress a warning that
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// 'size' might be used unitialized. It seems gcc can't
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// quite grok this spaghetti code ...
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int size = 0; /* size of converted field or string */
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char buf[BUF]; /* space for %c, %[diouxX], %[eEfgG] */
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char ox[2]; /* space for 0x hex-prefix */
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/*
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* Choose PADSIZE to trade efficiency vs size. If larger
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* printf fields occur frequently, increase PADSIZE (and make
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* the initialisers below longer).
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*/
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#define PADSIZE 16 /* pad chunk size */
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static char const blanks[PADSIZE] =
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{' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '};
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static char const zeroes[PADSIZE] =
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{'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'};
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/*
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* BEWARE, these `goto error' on error, and PAD uses `n'.
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*/
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#define PRINT(ptr, len) \
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do { if (sputn(ptr, len) != len) goto error; } while (0)
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#if 1
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#define PAD_SP(howmany) if (padn(' ', howmany) < 0) goto error;
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#define PAD_0(howmany) if (padn('0', howmany) < 0) goto error;
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#else
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#define PAD(howmany, with) { \
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if ((n = (howmany)) > 0) { \
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while (n > PADSIZE) { \
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PRINT(with, PADSIZE); \
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n -= PADSIZE; \
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} \
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PRINT(with, n); \
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} \
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}
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#define PAD_SP(howmany) PAD(howmany, blanks)
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#define PAD_0(howmany) PAD(howmany, zeroes)
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#endif
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/*
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* To extend shorts properly, we need both signed and unsigned
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* argument extraction methods.
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*/
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#define SARG() \
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(flags&LONGINT ? va_arg(ap, long) : \
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flags&SHORTINT ? (long)(short)va_arg(ap, int) : \
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(long)va_arg(ap, int))
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#define UARG() \
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(flags&LONGINT ? va_arg(ap, unsigned long) : \
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flags&SHORTINT ? (unsigned long)(unsigned short)va_arg(ap, int) : \
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(unsigned long)va_arg(ap, unsigned int))
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/* optimise cerr (and other unbuffered Unix files) */
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if (unbuffered())
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return help_vform(this, fmt0, ap);
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fmt = fmt0;
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ret = 0;
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/*
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* Scan the format for conversions (`%' character).
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*/
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for (;;) {
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for (fmark = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++)
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/* void */;
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if ((n = fmt - fmark) != 0) {
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PRINT(fmark, n);
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ret += n;
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}
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if (ch == '\0')
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goto done;
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fmt++; /* skip over '%' */
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flags = 0;
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dprec = 0;
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#if defined(FLOATING_POINT) && !defined (USE_DTOA)
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fpprec = 0;
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#endif
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width = 0;
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prec = -1;
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sign = '\0';
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rflag: ch = *fmt++;
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reswitch: switch (ch) {
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case ' ':
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/*
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* ``If the space and + flags both appear, the space
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* flag will be ignored.''
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* -- ANSI X3J11
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*/
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if (!sign)
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sign = ' ';
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goto rflag;
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case '#':
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flags |= ALT;
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goto rflag;
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case '*':
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/*
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* ``A negative field width argument is taken as a
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* - flag followed by a positive field width.''
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* -- ANSI X3J11
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* They don't exclude field widths read from args.
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*/
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if ((width = va_arg(ap, int)) >= 0)
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goto rflag;
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width = -width;
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/* FALLTHROUGH */
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case '-':
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flags |= LADJUST;
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flags &= ~ZEROPAD; /* '-' disables '0' */
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goto rflag;
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case '+':
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sign = '+';
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goto rflag;
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case '.':
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if ((ch = *fmt++) == '*') {
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n = va_arg(ap, int);
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prec = n < 0 ? -1 : n;
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goto rflag;
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}
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n = 0;
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while (is_digit(ch)) {
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n = 10 * n + to_digit(ch);
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ch = *fmt++;
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}
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prec = n < 0 ? -1 : n;
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goto reswitch;
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case '0':
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/*
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* ``Note that 0 is taken as a flag, not as the
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* beginning of a field width.''
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* -- ANSI X3J11
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*/
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if (!(flags & LADJUST))
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flags |= ZEROPAD; /* '-' disables '0' */
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goto rflag;
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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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n = 0;
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do {
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n = 10 * n + to_digit(ch);
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ch = *fmt++;
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} while (is_digit(ch));
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width = n;
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goto reswitch;
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#ifdef FLOATING_POINT
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case 'L':
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flags |= LONGDBL;
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goto rflag;
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#endif
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case 'h':
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flags |= SHORTINT;
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goto rflag;
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case 'l':
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flags |= LONGINT;
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goto rflag;
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case 'c':
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*(cp = buf) = va_arg(ap, int);
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size = 1;
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sign = '\0';
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break;
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case 'D':
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flags |= LONGINT;
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/*FALLTHROUGH*/
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case 'd':
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case 'i':
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_ulong = SARG();
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if ((long)_ulong < 0) {
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_ulong = -_ulong;
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sign = '-';
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}
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base = DEC;
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goto number;
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#ifdef FLOATING_POINT
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case 'e':
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case 'E':
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case 'f':
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case 'F':
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case 'g':
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case 'G':
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_double = va_arg(ap, double);
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#ifdef USE_DTOA
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{
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ios::fmtflags fmt_flags = 0;
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int fill = ' ';
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if (flags & ALT)
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fmt_flags |= ios::showpoint;
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if (flags & LADJUST)
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fmt_flags |= ios::left;
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else if (flags & ZEROPAD)
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fmt_flags |= ios::internal, fill = '0';
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n = __outfloat(_double, this, ch, width,
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prec < 0 ? DEFPREC : prec,
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fmt_flags, sign, fill);
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if (n < 0)
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goto error;
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ret += n;
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}
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// CHECK ERROR!
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continue;
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#else
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/*
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* don't do unrealistic precision; just pad it with
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* zeroes later, so buffer size stays rational.
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*/
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if (prec > MAXFRACT) {
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if ((ch != 'g' && ch != 'G') || (flags&ALT))
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fpprec = prec - MAXFRACT;
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prec = MAXFRACT;
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} else if (prec == -1)
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prec = DEFPREC;
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// __cvt_double may have to round up before the
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// "start" of its buffer, i.e.
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// ``intf("%.2f", (double)9.999);'';
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// if the first character is still NUL, it did.
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// softsign avoids negative 0 if _double < 0 but
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// no significant digits will be shown.
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cp = buf;
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*cp = '\0';
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size = __cvt_double(_double, prec, flags, &softsign,
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ch, cp, buf + sizeof(buf));
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if (softsign)
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sign = '-';
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if (*cp == '\0')
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cp++;
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break;
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#endif
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#endif /* FLOATING_POINT */
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case 'n':
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if (flags & LONGINT)
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*va_arg(ap, long *) = ret;
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else if (flags & SHORTINT)
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*va_arg(ap, short *) = ret;
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else
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*va_arg(ap, int *) = ret;
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continue; /* no output */
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case 'O':
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flags |= LONGINT;
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/*FALLTHROUGH*/
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case 'o':
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_ulong = UARG();
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base = OCT;
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goto nosign;
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case 'p':
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/*
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* ``The argument shall be a pointer to void. The
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* value of the pointer is converted to a sequence
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* of printable characters, in an implementation-
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* defined manner.''
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* -- ANSI X3J11
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*/
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/* NOSTRICT */
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_ulong = (unsigned long)va_arg(ap, void *);
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base = HEX;
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flags |= HEXPREFIX;
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ch = 'x';
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goto nosign;
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case 's':
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if ((cp = va_arg(ap, char *)) == NULL)
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cp = "(null)";
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if (prec >= 0) {
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/*
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* can't use strlen; can only look for the
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* NUL in the first `prec' characters, and
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* strlen() will go further.
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*/
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char *p = (char*)memchr(cp, 0, prec);
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if (p != NULL) {
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size = p - cp;
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if (size > prec)
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size = prec;
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} else
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size = prec;
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} else
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size = strlen(cp);
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sign = '\0';
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break;
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case 'U':
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flags |= LONGINT;
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/*FALLTHROUGH*/
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case 'u':
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_ulong = UARG();
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base = DEC;
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goto nosign;
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case 'X':
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case 'x':
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_ulong = UARG();
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base = HEX;
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/* leading 0x/X only if non-zero */
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if (flags & ALT && _ulong != 0)
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flags |= HEXPREFIX;
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/* unsigned conversions */
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nosign: sign = '\0';
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/*
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* ``... diouXx conversions ... if a precision is
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* specified, the 0 flag will be ignored.''
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* -- ANSI X3J11
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*/
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number: if ((dprec = prec) >= 0)
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flags &= ~ZEROPAD;
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/*
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* ``The result of converting a zero value with an
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* explicit precision of zero is no characters.''
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* -- ANSI X3J11
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*/
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cp = buf + BUF;
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if (_ulong != 0 || prec != 0) {
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char *xdigs; /* digits for [xX] conversion */
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/*
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* unsigned mod is hard, and unsigned mod
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* by a constant is easier than that by
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* a variable; hence this switch.
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*/
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switch (base) {
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case OCT:
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do {
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*--cp = to_char(_ulong & 7);
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_ulong >>= 3;
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} while (_ulong);
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/* handle octal leading 0 */
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if (flags & ALT && *cp != '0')
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*--cp = '0';
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break;
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case DEC:
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/* many numbers are 1 digit */
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while (_ulong >= 10) {
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*--cp = to_char(_ulong % 10);
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_ulong /= 10;
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}
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*--cp = to_char(_ulong);
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break;
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case HEX:
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if (ch == 'X')
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xdigs = "0123456789ABCDEF";
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else /* ch == 'x' || ch == 'p' */
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xdigs = "0123456789abcdef";
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do {
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*--cp = xdigs[_ulong & 15];
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_ulong >>= 4;
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} while (_ulong);
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break;
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default:
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cp = "bug in vform: bad base";
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goto skipsize;
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}
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}
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size = buf + BUF - cp;
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skipsize:
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break;
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default: /* "%?" prints ?, unless ? is NUL */
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if (ch == '\0')
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goto done;
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/* pretend it was %c with argument ch */
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cp = buf;
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*cp = ch;
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size = 1;
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sign = '\0';
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break;
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}
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/*
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* All reasonable formats wind up here. At this point,
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* `cp' points to a string which (if not flags&LADJUST)
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* should be padded out to `width' places. If
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* flags&ZEROPAD, it should first be prefixed by any
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* sign or other prefix; otherwise, it should be blank
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* padded before the prefix is emitted. After any
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* left-hand padding and prefixing, emit zeroes
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* required by a decimal [diouxX] precision, then print
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* the string proper, then emit zeroes required by any
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* leftover floating precision; finally, if LADJUST,
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* pad with blanks.
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*/
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/*
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* compute actual size, so we know how much to pad.
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*/
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#if defined(FLOATING_POINT) && !defined (USE_DTOA)
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fieldsz = size + fpprec;
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#else
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fieldsz = size;
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#endif
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dpad = dprec - size;
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if (dpad < 0)
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dpad = 0;
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if (sign)
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fieldsz++;
|
|
else if (flags & HEXPREFIX)
|
|
fieldsz += 2;
|
|
fieldsz += dpad;
|
|
|
|
/* right-adjusting blank padding */
|
|
if ((flags & (LADJUST|ZEROPAD)) == 0)
|
|
PAD_SP(width - fieldsz);
|
|
|
|
/* prefix */
|
|
if (sign) {
|
|
PRINT(&sign, 1);
|
|
} else if (flags & HEXPREFIX) {
|
|
ox[0] = '0';
|
|
ox[1] = ch;
|
|
PRINT(ox, 2);
|
|
}
|
|
|
|
/* right-adjusting zero padding */
|
|
if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD)
|
|
PAD_0(width - fieldsz);
|
|
|
|
/* leading zeroes from decimal precision */
|
|
PAD_0(dpad);
|
|
|
|
/* the string or number proper */
|
|
PRINT(cp, size);
|
|
|
|
#if defined(FLOATING_POINT) && !defined (USE_DTOA)
|
|
/* trailing f.p. zeroes */
|
|
PAD_0(fpprec);
|
|
#endif
|
|
|
|
/* left-adjusting padding (always blank) */
|
|
if (flags & LADJUST)
|
|
PAD_SP(width - fieldsz);
|
|
|
|
/* finally, adjust ret */
|
|
ret += width > fieldsz ? width : fieldsz;
|
|
|
|
}
|
|
done:
|
|
return ret;
|
|
error:
|
|
return EOF;
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
#if defined(FLOATING_POINT) && !defined(USE_DTOA)
|
|
|
|
static char *exponent(register char *p, register int exp, int fmtch)
|
|
{
|
|
register char *t;
|
|
char expbuf[MAXEXP];
|
|
|
|
*p++ = fmtch;
|
|
if (exp < 0) {
|
|
exp = -exp;
|
|
*p++ = '-';
|
|
}
|
|
else
|
|
*p++ = '+';
|
|
t = expbuf + MAXEXP;
|
|
if (exp > 9) {
|
|
do {
|
|
*--t = to_char(exp % 10);
|
|
} while ((exp /= 10) > 9);
|
|
*--t = to_char(exp);
|
|
for (; t < expbuf + MAXEXP; *p++ = *t++);
|
|
}
|
|
else {
|
|
*p++ = '0';
|
|
*p++ = to_char(exp);
|
|
}
|
|
return (p);
|
|
}
|
|
|
|
static char * round(double fract, int *exp,
|
|
register char *start, register char *end,
|
|
char ch, int *signp)
|
|
{
|
|
double tmp;
|
|
|
|
if (fract)
|
|
(void)modf(fract * 10, &tmp);
|
|
else
|
|
tmp = to_digit(ch);
|
|
if (tmp > 4)
|
|
for (;; --end) {
|
|
if (*end == '.')
|
|
--end;
|
|
if (++*end <= '9')
|
|
break;
|
|
*end = '0';
|
|
if (end == start) {
|
|
if (exp) { /* e/E; increment exponent */
|
|
*end = '1';
|
|
++*exp;
|
|
}
|
|
else { /* f; add extra digit */
|
|
*--end = '1';
|
|
--start;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
/* ``"%.3f", (double)-0.0004'' gives you a negative 0. */
|
|
else if (*signp == '-')
|
|
for (;; --end) {
|
|
if (*end == '.')
|
|
--end;
|
|
if (*end != '0')
|
|
break;
|
|
if (end == start)
|
|
*signp = 0;
|
|
}
|
|
return (start);
|
|
}
|
|
|
|
int __cvt_double(double number, register int prec, int flags, int *signp,
|
|
int fmtch, char *startp, char *endp)
|
|
{
|
|
register char *p, *t;
|
|
register double fract;
|
|
int dotrim = 0, expcnt, gformat = 0;
|
|
double integer, tmp;
|
|
|
|
expcnt = 0;
|
|
if (number < 0) {
|
|
number = -number;
|
|
*signp = '-';
|
|
} else
|
|
*signp = 0;
|
|
|
|
fract = modf(number, &integer);
|
|
|
|
/* get an extra slot for rounding. */
|
|
t = ++startp;
|
|
|
|
/*
|
|
* get integer portion of number; put into the end of the buffer; the
|
|
* .01 is added for modf(356.0 / 10, &integer) returning .59999999...
|
|
*/
|
|
for (p = endp - 1; integer; ++expcnt) {
|
|
tmp = modf(integer / 10, &integer);
|
|
*p-- = to_char((int)((tmp + .01) * 10));
|
|
}
|
|
switch (fmtch) {
|
|
case 'f':
|
|
case 'F':
|
|
/* reverse integer into beginning of buffer */
|
|
if (expcnt)
|
|
for (; ++p < endp; *t++ = *p);
|
|
else
|
|
*t++ = '0';
|
|
/*
|
|
* if precision required or alternate flag set, add in a
|
|
* decimal point.
|
|
*/
|
|
if (prec || flags&ALT)
|
|
*t++ = '.';
|
|
/* if requires more precision and some fraction left */
|
|
if (fract) {
|
|
if (prec)
|
|
do {
|
|
fract = modf(fract * 10, &tmp);
|
|
*t++ = to_char((int)tmp);
|
|
} while (--prec && fract);
|
|
if (fract)
|
|
startp = round(fract, (int *)NULL, startp,
|
|
t - 1, (char)0, signp);
|
|
}
|
|
for (; prec--; *t++ = '0');
|
|
break;
|
|
case 'e':
|
|
case 'E':
|
|
eformat: if (expcnt) {
|
|
*t++ = *++p;
|
|
if (prec || flags&ALT)
|
|
*t++ = '.';
|
|
/* if requires more precision and some integer left */
|
|
for (; prec && ++p < endp; --prec)
|
|
*t++ = *p;
|
|
/*
|
|
* if done precision and more of the integer component,
|
|
* round using it; adjust fract so we don't re-round
|
|
* later.
|
|
*/
|
|
if (!prec && ++p < endp) {
|
|
fract = 0;
|
|
startp = round((double)0, &expcnt, startp,
|
|
t - 1, *p, signp);
|
|
}
|
|
/* adjust expcnt for digit in front of decimal */
|
|
--expcnt;
|
|
}
|
|
/* until first fractional digit, decrement exponent */
|
|
else if (fract) {
|
|
/* adjust expcnt for digit in front of decimal */
|
|
for (expcnt = -1;; --expcnt) {
|
|
fract = modf(fract * 10, &tmp);
|
|
if (tmp)
|
|
break;
|
|
}
|
|
*t++ = to_char((int)tmp);
|
|
if (prec || flags&ALT)
|
|
*t++ = '.';
|
|
}
|
|
else {
|
|
*t++ = '0';
|
|
if (prec || flags&ALT)
|
|
*t++ = '.';
|
|
}
|
|
/* if requires more precision and some fraction left */
|
|
if (fract) {
|
|
if (prec)
|
|
do {
|
|
fract = modf(fract * 10, &tmp);
|
|
*t++ = to_char((int)tmp);
|
|
} while (--prec && fract);
|
|
if (fract)
|
|
startp = round(fract, &expcnt, startp,
|
|
t - 1, (char)0, signp);
|
|
}
|
|
/* if requires more precision */
|
|
for (; prec--; *t++ = '0');
|
|
|
|
/* unless alternate flag, trim any g/G format trailing 0's */
|
|
if (gformat && !(flags&ALT)) {
|
|
while (t > startp && *--t == '0');
|
|
if (*t == '.')
|
|
--t;
|
|
++t;
|
|
}
|
|
t = exponent(t, expcnt, fmtch);
|
|
break;
|
|
case 'g':
|
|
case 'G':
|
|
/* a precision of 0 is treated as a precision of 1. */
|
|
if (!prec)
|
|
++prec;
|
|
/*
|
|
* ``The style used depends on the value converted; style e
|
|
* will be used only if the exponent resulting from the
|
|
* conversion is less than -4 or greater than the precision.''
|
|
* -- ANSI X3J11
|
|
*/
|
|
if (expcnt > prec || (!expcnt && fract && fract < .0001)) {
|
|
/*
|
|
* g/G format counts "significant digits, not digits of
|
|
* precision; for the e/E format, this just causes an
|
|
* off-by-one problem, i.e. g/G considers the digit
|
|
* before the decimal point significant and e/E doesn't
|
|
* count it as precision.
|
|
*/
|
|
--prec;
|
|
fmtch -= 2; /* G->E, g->e */
|
|
gformat = 1;
|
|
goto eformat;
|
|
}
|
|
/*
|
|
* reverse integer into beginning of buffer,
|
|
* note, decrement precision
|
|
*/
|
|
if (expcnt)
|
|
for (; ++p < endp; *t++ = *p, --prec);
|
|
else
|
|
*t++ = '0';
|
|
/*
|
|
* if precision required or alternate flag set, add in a
|
|
* decimal point. If no digits yet, add in leading 0.
|
|
*/
|
|
if (prec || flags&ALT) {
|
|
dotrim = 1;
|
|
*t++ = '.';
|
|
}
|
|
else
|
|
dotrim = 0;
|
|
/* if requires more precision and some fraction left */
|
|
if (fract) {
|
|
if (prec) {
|
|
/* If no integer part, don't count initial
|
|
* zeros as significant digits. */
|
|
do {
|
|
fract = modf(fract * 10, &tmp);
|
|
*t++ = to_char((int)tmp);
|
|
} while(!tmp && !expcnt);
|
|
while (--prec && fract) {
|
|
fract = modf(fract * 10, &tmp);
|
|
*t++ = to_char((int)tmp);
|
|
}
|
|
}
|
|
if (fract)
|
|
startp = round(fract, (int *)NULL, startp,
|
|
t - 1, (char)0, signp);
|
|
}
|
|
/* alternate format, adds 0's for precision, else trim 0's */
|
|
if (flags&ALT)
|
|
for (; prec--; *t++ = '0');
|
|
else if (dotrim) {
|
|
while (t > startp && *--t == '0');
|
|
if (*t != '.')
|
|
++t;
|
|
}
|
|
}
|
|
return (t - startp);
|
|
}
|
|
|
|
#endif /* defined(FLOATING_POINT) && !defined(USE_DTOA) */
|
|
|
|
int streambuf::form(char const *format ...)
|
|
{
|
|
va_list ap;
|
|
va_start(ap, format);
|
|
int count = vform(format, ap);
|
|
va_end(ap);
|
|
return count;
|
|
}
|