vfprintf.c

Newlib 嵌入式 C库 标准实现代码

	       ? args[numargs++].val_##type = va_arg (ap, type)		\
	       : va_arg (ap, type))))
#else
# define GET_ARG(n, ap, type) (va_arg (ap, type))
#endif

	/*
	 * To extend shorts properly, we need both signed and unsigned
	 * argument extraction methods.
	 */
#ifndef _NO_LONGLONG
#define	SARG() \
	(flags&QUADINT ? GET_ARG (N, ap, quad_t) : \
	    flags&LONGINT ? GET_ARG (N, ap, long) : \
	    flags&SHORTINT ? (long)(short)GET_ARG (N, ap, int) : \
	    flags&CHARINT ? (long)(signed char)GET_ARG (N, ap, int) : \
	    (long)GET_ARG (N, ap, int))
#define	UARG() \
	(flags&QUADINT ? GET_ARG (N, ap, u_quad_t) : \
	    flags&LONGINT ? GET_ARG (N, ap, u_long) : \
	    flags&SHORTINT ? (u_long)(u_short)GET_ARG (N, ap, int) : \
	    flags&CHARINT ? (u_long)(unsigned char)GET_ARG (N, ap, int) : \
	    (u_long)GET_ARG (N, ap, u_int))
#else
#define	SARG() \
	(flags&LONGINT ? GET_ARG (N, ap, long) : \
	    flags&SHORTINT ? (long)(short)GET_ARG (N, ap, int) : \
	    flags&CHARINT ? (long)(signed char)GET_ARG (N, ap, int) : \
	    (long)GET_ARG (N, ap, int))
#define	UARG() \
	(flags&LONGINT ? GET_ARG (N, ap, u_long) : \
	    flags&SHORTINT ? (u_long)(u_short)GET_ARG (N, ap, int) : \
	    flags&CHARINT ? (u_long)(unsigned char)GET_ARG (N, ap, int) : \
	    (u_long)GET_ARG (N, ap, u_int))
#endif

	CHECK_INIT (data, fp);
	_flockfile (fp);

	/* sorry, fprintf(read_only_file, "") returns EOF, not 0 */
	if (cantwrite (data, fp)) {
		_funlockfile (fp);	
		return (EOF);
	}

	/* optimise fprintf(stderr) (and other unbuffered Unix files) */
	if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) &&
	    fp->_file >= 0) {
		_funlockfile (fp);
		return (__sbprintf (data, fp, fmt0, ap));
	}

	fmt = (char *)fmt0;
	uio.uio_iov = iovp = iov;
	uio.uio_resid = 0;
	uio.uio_iovcnt = 0;
	ret = 0;
#ifndef _NO_POS_ARGS
	arg_index = 0;
	saved_fmt = NULL;
	arg_type[0] = -1;
	numargs = 0;
	is_pos_arg = 0;
#endif

	/*
	 * Scan the format for conversions (`%' character).
	 */
	for (;;) {
	        cp = fmt;
#ifdef _MB_CAPABLE
	        while ((n = _mbtowc_r (data, &wc, fmt, MB_CUR_MAX, &state)) > 0) {
                    if (wc == '%')
                        break;
                    fmt += n;
		}
#else
                while (*fmt != '\0' && *fmt != '%')
                    fmt += 1;
#endif
		if ((m = fmt - cp) != 0) {
			PRINT (cp, m);
			ret += m;
		}
#ifdef _MB_CAPABLE
		if (n <= 0)
                    goto done;
#else
                if (*fmt == '\0')
                    goto done;
#endif
		fmt_anchor = fmt;
		fmt++;		/* skip over '%' */

		flags = 0;
		dprec = 0;
		width = 0;
		prec = -1;
		sign = '\0';
#ifndef _NO_POS_ARGS
		N = arg_index;
		is_pos_arg = 0;
#endif

rflag:		ch = *fmt++;
reswitch:	switch (ch) {
#ifdef _WANT_IO_C99_FORMATS
		case '\'':
		  /* The ' flag is required by POSIX, but not C99.
		     In the C locale, LC_NUMERIC requires
		     thousands_sep to be the empty string.  And since
		     no other locales are supported (yet), this flag
		     is currently a no-op.  */
		  goto rflag;
#endif
		case ' ':
			/*
			 * ``If the space and + flags both appear, the space
			 * flag will be ignored.''
			 *	-- ANSI X3J11
			 */
			if (!sign)
				sign = ' ';
			goto rflag;
		case '#':
			flags |= ALT;
			goto rflag;
		case '*':
#ifndef _NO_POS_ARGS
			/* we must check for positional arg used for dynamic width */
			n = N;
			old_is_pos_arg = is_pos_arg;
			is_pos_arg = 0;
			if (is_digit (*fmt)) {
				char *old_fmt = fmt;

				n = 0;
				ch = *fmt++;
				do {
					n = 10 * n + to_digit (ch);
					ch = *fmt++;
				} while (is_digit (ch));

				if (ch == '$') {
					if (n <= MAX_POS_ARGS) {
						n -= 1;
						is_pos_arg = 1;
					}
					else
						goto error;
				}
				else {
					fmt = old_fmt;
					goto rflag;
				}
			}
#endif /* !_NO_POS_ARGS */

			/*
			 * ``A negative field width argument is taken as a
			 * - flag followed by a positive field width.''
			 *	-- ANSI X3J11
			 * They don't exclude field widths read from args.
			 */
			width = GET_ARG (n, ap, int);
#ifndef _NO_POS_ARGS
			is_pos_arg = old_is_pos_arg;
#endif
			if (width >= 0)
				goto rflag;
			width = -width;
			/* FALLTHROUGH */
		case '-':
			flags |= LADJUST;
			goto rflag;
		case '+':
			sign = '+';
			goto rflag;
		case '.':
			if ((ch = *fmt++) == '*') {
#ifndef _NO_POS_ARGS
				/* we must check for positional arg used for dynamic width */
				n = N;
				old_is_pos_arg = is_pos_arg;
				is_pos_arg = 0;
				if (is_digit (*fmt)) {
					char *old_fmt = fmt;

					n = 0;
					ch = *fmt++;
					do {
						n = 10 * n + to_digit (ch);
						ch = *fmt++;
					} while (is_digit (ch));

					if (ch == '$') {
						if (n <= MAX_POS_ARGS) {
							n -= 1;
							is_pos_arg = 1;
						}
						else
							goto error;
					}
					else {
						fmt = old_fmt;
						goto rflag;
					}
				}
#endif /* !_NO_POS_ARGS */
				prec = GET_ARG (n, ap, int);
#ifndef _NO_POS_ARGS
				is_pos_arg = old_is_pos_arg;
#endif
				if (prec < 0)
					prec = -1;
				goto rflag;
			}
			n = 0;
			while (is_digit (ch)) {
				n = 10 * n + to_digit (ch);
				ch = *fmt++;
			}
			prec = n < 0 ? -1 : n;
			goto reswitch;
		case '0':
			/*
			 * ``Note that 0 is taken as a flag, not as the
			 * beginning of a field width.''
			 *	-- ANSI X3J11
			 */
			flags |= ZEROPAD;
			goto rflag;
		case '1': case '2': case '3': case '4':
		case '5': case '6': case '7': case '8': case '9':
			n = 0;
			do {
				n = 10 * n + to_digit (ch);
				ch = *fmt++;
			} while (is_digit (ch));
#ifndef _NO_POS_ARGS
			if (ch == '$') {
				if (n <= MAX_POS_ARGS) {
					N = n - 1;
					is_pos_arg = 1;
					goto rflag;
				}
				else
					goto error;
			}
#endif /* !_NO_POS_ARGS */
			width = n;
			goto reswitch;
#ifdef FLOATING_POINT
		case 'L':
			flags |= LONGDBL;
			goto rflag;
#endif
		case 'h':
#ifdef _WANT_IO_C99_FORMATS
			if (*fmt == 'h') {
				fmt++;
				flags |= CHARINT;
			} else
#endif
				flags |= SHORTINT;
			goto rflag;
		case 'l':
#if defined _WANT_IO_C99_FORMATS || !defined _NO_LONGLONG
			if (*fmt == 'l') {
				fmt++;
				flags |= QUADINT;
			} else
#endif
				flags |= LONGINT;
			goto rflag;
		case 'q': /* extension */
			flags |= QUADINT;
			goto rflag;
#ifdef _WANT_IO_C99_FORMATS
		case 'j':
		  if (sizeof (intmax_t) == sizeof (long))
		    flags |= LONGINT;
		  else
		    flags |= QUADINT;
		  goto rflag;
		case 'z':
		  if (sizeof (size_t) < sizeof (int))
		    /* POSIX states size_t is 16 or more bits, as is short.  */
		    flags |= SHORTINT;
		  else if (sizeof (size_t) == sizeof (int))
		    /* no flag needed */;
		  else if (sizeof (size_t) <= sizeof (long))
		    flags |= LONGINT;
		  else
		    /* POSIX states that at least one programming
		       environment must support size_t no wider than
		       long, but that means other environments can
		       have size_t as wide as long long.  */
		    flags |= QUADINT;
		  goto rflag;
		case 't':
		  if (sizeof (ptrdiff_t) < sizeof (int))
		    /* POSIX states ptrdiff_t is 16 or more bits, as
		       is short.  */
		    flags |= SHORTINT;
		  else if (sizeof (ptrdiff_t) == sizeof (int))
		    /* no flag needed */;
		  else if (sizeof (ptrdiff_t) <= sizeof (long))
		    flags |= LONGINT;
		  else
		    /* POSIX states that at least one programming
		       environment must support ptrdiff_t no wider than
		       long, but that means other environments can
		       have ptrdiff_t as wide as long long.  */
		    flags |= QUADINT;
		  goto rflag;
		case 'C':
#endif /* _WANT_IO_C99_FORMATS */
		case 'c':
			cp = buf;
#ifdef _MB_CAPABLE
			if (ch == 'C' || (flags & LONGINT)) {
				mbstate_t ps;

				memset ((_PTR)&ps, '\0', sizeof (mbstate_t));
				if ((size = (int)_wcrtomb_r (data, cp,
					       (wchar_t)GET_ARG (N, ap, wint_t),
						&ps)) == -1) {
					fp->_flags |= __SERR;
					goto error; 
				}
			}
			else
#endif /* _MB_CAPABLE */
			{
				*cp = GET_ARG (N, ap, int);
				size = 1;
			}
			sign = '\0';
			break;
		case 'D':  /* extension */
			flags |= LONGINT;
			/*FALLTHROUGH*/
		case 'd':
		case 'i':
			_uquad = SARG ();
#ifndef _NO_LONGLONG
			if ((quad_t)_uquad < 0)
#else
			if ((long) _uquad < 0)
#endif
			{

				_uquad = -_uquad;
				sign = '-';
			}
			base = DEC;
			goto number;
#ifdef FLOATING_POINT
# ifdef _WANT_IO_C99_FORMATS
		case 'a':
		case 'A':
		case 'F':
# endif
		case 'e':
		case 'E':
		case 'f':
		case 'g':
		case 'G':
# ifdef _NO_LONGDBL
			if (flags & LONGDBL) {
				_fpvalue = (double) GET_ARG (N, ap, _LONG_DOUBLE);
			} else {
				_fpvalue = GET_ARG (N, ap, double);
			}

			/* do this before tricky precision changes

			   If the output is infinite or NaN, leading
			   zeros are not permitted.  Otherwise, scanf
			   could not read what printf wrote.
			 */
			if (isinf (_fpvalue)) {
				if (_fpvalue < 0)
					sign = '-';
				if (ch <= 'G') /* 'A', 'E', 'F', or 'G' */
					cp = "INF";
				else
					cp = "inf";
				size = 3;
				flags &= ~ZEROPAD;
				break;
			}
			if (isnan (_fpvalue)) {
				if (ch <= 'G') /* 'A', 'E', 'F', or 'G' */
					cp = "NAN";
				else
					cp = "nan";
				size = 3;
				flags &= ~ZEROPAD;
				break;
			}

# else /* !_NO_LONGDBL */

			if (flags & LONGDBL) {
				_fpvalue = GET_ARG (N, ap, _LONG_DOUBLE);
			} else {
				_fpvalue = (_LONG_DOUBLE)GET_ARG (N, ap, double);
			}

			/* do this before tricky precision changes */
			expt = _ldcheck (&_fpvalue);
			if (expt == 2) {
				if (_fpvalue < 0)
					sign = '-';
				if (ch <= 'G') /* 'A', 'E', 'F', or 'G' */
					cp = "INF";
				else
					cp = "inf";
				size = 3;
				flags &= ~ZEROPAD;
				break;
			}
			if (expt == 1) {
				if (ch <= 'G') /* 'A', 'E', 'F', or 'G' */
					cp = "NAN";
				else
					cp = "nan";
				size = 3;
				flags &= ~ZEROPAD;
				break;
			}
# endif /* !_NO_LONGDBL */

# ifdef _WANT_IO_C99_FORMATS
			if (ch == 'a' || ch == 'A') {
				ox[0] = '0';
				ox[1] = ch == 'a' ? 'x' : 'X';
				flags |= HEXPREFIX;
				if (prec >= BUF)
				  {
				    if ((malloc_buf =
					 (char *)_malloc_r (data, prec + 1))
					== NULL)
				      {
					fp->_flags |= __SERR;
					goto error;
				      }
				    cp = malloc_buf;
				  }
				else
				  cp = buf;
			} else
# endif /* _WANT_IO_C99_FORMATS */
			if (prec == -1) {
				prec = DEFPREC;
			} else if ((ch == 'g' || ch == 'G') && prec == 0) {
				prec = 1;
			}

			flags |= FPT;

			cp = cvt (data, _fpvalue, prec, flags, &softsign,
				  &expt, ch, &ndig, cp);

			if (ch == 'g' || ch == 'G') {
				if (expt <= -4 || expt > prec)
					ch -= 2; /* 'e' or 'E' */
				else
					ch = 'g';
			}
# ifdef _WANT_IO_C99_FORMATS
			else if (ch == 'F')
				ch = 'f';
# endif
			if (ch <= 'e') {	/* 'a', 'A', 'e', or 'E' fmt */
				--expt;
				expsize = exponent (expstr, expt, ch);
				size = expsize + ndig;
				if (ndig > 1 || flags & ALT)
					++size;
			} else if (ch == 'f') {		/* f fmt */