vfprintf.c

Newlib 嵌入式 C库 标准实现代码

				*va_arg(ap, long *) = ret;
			else if (flags & SHORTINT)
				*va_arg(ap, short *) = ret;
			else
				*va_arg(ap, int *) = ret;
			continue;	/* no output */
		case 'O':
			flags |= LONGINT;
			/*FALLTHROUGH*/
		case 'o':
#ifdef __ALTIVEC__
		        if (!(flags & VECTOR) && vec_sep != ' ') 
			  {
			    fmt = format_anchor;
			    continue;
			  }
#endif /* __ALTIVEC__ */
			_uquad = UARG();
			base = OCT;
			goto nosign;
		case 'p':
			/*
			 * ``The argument shall be a pointer to void.  The
			 * value of the pointer is converted to a sequence
			 * of printable characters, in an implementation-
			 * defined manner.''
			 *	-- ANSI X3J11
			 */
			/* NOSTRICT */
#ifdef __ALTIVEC__
		        if (flags & VECTOR)
		          _uquad = UARG();
		        else if (vec_sep != ' ')
			  {
			    fmt = format_anchor;
			    continue;
			  }
			else
#endif /* __ALTIVEC__ */
		          _uquad = (u_long)(unsigned _POINTER_INT)va_arg(ap, void *);
			base = HEX;
			xdigs = "0123456789abcdef";
			flags |= HEXPREFIX;
			ch = 'x';
			goto nosign;
		case 's':
#ifdef __ALTIVEC__
		        if (flags & VECTOR)
			  {
			    fmt = format_anchor;
			    continue;
			  }
#endif /* __ALTIVEC__ */
			if ((cp = va_arg(ap, char *)) == NULL)
				cp = "(null)";
			if (prec >= 0) {
				/*
				 * can't use strlen; can only look for the
				 * NUL in the first `prec' characters, and
				 * strlen() will go further.
				 */
				char *p = memchr(cp, 0, prec);

				if (p != NULL) {
					size = p - cp;
					if (size > prec)
						size = prec;
				} else
					size = prec;
			} else
				size = strlen(cp);
			sign = '\0';
			break;
		case 'U':
			flags |= LONGINT;
			/*FALLTHROUGH*/
		case 'u':
#ifdef __ALTIVEC__
		        if (!(flags & VECTOR) && vec_sep != ' ') 
			  {
			    fmt = format_anchor;
			    continue;
			  }
#endif /* __ALTIVEC__ */
			_uquad = UARG();
			base = DEC;
			goto nosign;
		case 'X':
			xdigs = "0123456789ABCDEF";
			goto hex;
		case 'x':
			xdigs = "0123456789abcdef";
#ifdef __ALTIVEC__
		        if (!(flags & VECTOR) && vec_sep != ' ') 
			  {
			    fmt = format_anchor;
			    continue;
			  }
#endif /* __ALTIVEC__ */
hex:			_uquad = UARG();
			base = HEX;
			/* leading 0x/X only if non-zero */
			if (flags & ALT && _uquad != 0)
				flags |= HEXPREFIX;

			/* unsigned conversions */
nosign:			sign = '\0';
			/*
			 * ``... diouXx conversions ... if a precision is
			 * specified, the 0 flag will be ignored.''
			 *	-- ANSI X3J11
			 */
number:			if ((dprec = prec) >= 0)
				flags &= ~ZEROPAD;

			/*
			 * ``The result of converting a zero value with an
			 * explicit precision of zero is no characters.''
			 *	-- ANSI X3J11
			 */
			cp = buf + BUF;
			if (_uquad != 0 || prec != 0) {
				/*
				 * Unsigned mod is hard, and unsigned mod
				 * by a constant is easier than that by
				 * a variable; hence this switch.
				 */
				switch (base) {
				case OCT:
					do {
						*--cp = to_char(_uquad & 7);
						_uquad >>= 3;
					} while (_uquad);
					/* handle octal leading 0 */
					if (flags & ALT && *cp != '0')
						*--cp = '0';
					break;

				case DEC:
					/* many numbers are 1 digit */
					while (_uquad >= 10) {
						*--cp = to_char(_uquad % 10);
						_uquad /= 10;
					}
					*--cp = to_char(_uquad);
					break;

				case HEX:
					do {
						*--cp = xdigs[_uquad & 15];
						_uquad >>= 4;
					} while (_uquad);
					break;

				default:
					cp = "bug in vfprintf: bad base";
					size = strlen(cp);
					goto skipsize;
				}
			}
                       /*
			* ...result is to be converted to an 'alternate form'.
			* For o conversion, it increases the precision to force
			* the first digit of the result to be a zero."
			*     -- ANSI X3J11
			*
			* To demonstrate this case, compile and run:
                        *    printf ("%#.0o",0);
			*/
                       else if (base == OCT && (flags & ALT))
                         *--cp = '0';

			size = buf + BUF - cp;
		skipsize:
			break;
		default:	/* "%?" prints ?, unless ? is NUL */
			flags &= ~VECTOR;
			if (ch == '\0')
				goto done;
			/* pretend it was %c with argument ch */
			cp = buf;
			*cp = ch;
			size = 1;
			sign = '\0';
			break;
		}

		/*
		 * All reasonable formats wind up here.  At this point, `cp'
		 * points to a string which (if not flags&LADJUST) should be
		 * padded out to `width' places.  If flags&ZEROPAD, it should
		 * first be prefixed by any sign or other prefix; otherwise,
		 * it should be blank padded before the prefix is emitted.
		 * After any left-hand padding and prefixing, emit zeroes
		 * required by a decimal [diouxX] precision, then print the
		 * string proper, then emit zeroes required by any leftover
		 * floating precision; finally, if LADJUST, pad with blanks.
		 *
		 * Compute actual size, so we know how much to pad.
		 * size excludes decimal prec; realsz includes it.
		 */
		realsz = dprec > size ? dprec : size;
		if (sign)
			realsz++;
		else if (flags & HEXPREFIX)
			realsz+= 2;

		/* right-adjusting blank padding */
		if ((flags & (LADJUST|ZEROPAD)) == 0)
			PAD(width - realsz, blanks);

		/* 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(width - realsz, zeroes);

		/* leading zeroes from decimal precision */
		PAD(dprec - size, zeroes);

		/* the string or number proper */
#ifdef FLOATING_POINT
		if ((flags & FPT) == 0) {
#ifdef __SPE__
		        if (flags & FIXEDPOINT) {
				if (_uquad == 0 && !sign) {
					/* kludge for __dtoa irregularity */
					PRINT("0", 1);
					if (expt < ndig || (flags & ALT) != 0) {
						PRINT(decimal_point, 1);
						PAD(ndig - 1, zeroes);
					}
				} else if (expt <= 0) {
					PRINT("0", 1);
					if(expt || ndig) {
						PRINT(decimal_point, 1);
						PAD(-expt, zeroes);
						PRINT(cp, ndig);
					}
				} else if (expt >= ndig) {
					PRINT(cp, ndig);
					PAD(expt - ndig, zeroes);
					if (flags & ALT)
						PRINT(".", 1);
				} else {
					PRINT(cp, expt);
					cp += expt;
					PRINT(".", 1);
					PRINT(cp, ndig-expt);
				}
		        } else
#endif /* __SPE__ */
 			        PRINT(cp, size);
		} else {	/* glue together f_p fragments */
			if (ch >= 'f') {	/* 'f' or 'g' */
				if (_fpvalue == 0) {
					/* kludge for __dtoa irregularity */
					PRINT("0", 1);
					if (expt < ndig || (flags & ALT) != 0) {
						PRINT(decimal_point, 1);
						PAD(ndig - 1, zeroes);
					}
				} else if (expt <= 0) {
					PRINT("0", 1);
					if(expt || ndig) {
						PRINT(decimal_point, 1);
						PAD(-expt, zeroes);
						PRINT(cp, ndig);
					}
				} else if (expt >= ndig) {
					PRINT(cp, ndig);
					PAD(expt - ndig, zeroes);
					if (flags & ALT)
						PRINT(".", 1);
				} else {
					PRINT(cp, expt);
					cp += expt;
					PRINT(".", 1);
					PRINT(cp, ndig-expt);
				}
			} else {	/* 'e' or 'E' */
				if (ndig > 1 || flags & ALT) {
					ox[0] = *cp++;
					ox[1] = '.';
					PRINT(ox, 2);
                                       if (_fpvalue) {
						PRINT(cp, ndig-1);
					} else	/* 0.[0..] */
						/* __dtoa irregularity */
						PAD(ndig - 1, zeroes);
				} else	/* XeYYY */
					PRINT(cp, 1);
				PRINT(expstr, expsize);
			}
		}
#else
		PRINT(cp, size);
#endif
		/* left-adjusting padding (always blank) */
		if (flags & LADJUST)
			PAD(width - realsz, blanks);

		/* finally, adjust ret */
		ret += width > realsz ? width : realsz;

#ifdef __ALTIVEC__		
		if ((flags & VECTOR) && vec_print_count-- > 1)
		  {
		    /* add vector separator */
		    if (ch != 'c' || vec_sep != ' ')
		      {
		        PRINT(&vec_sep, 1);
		        ret += 1;
		      }
		    FLUSH();
		    sign = old_sign;
		    ch = old_ch;
		    goto reswitch;
		  }
#endif /* __ALTIVEC__ */
		FLUSH();	/* copy out the I/O vectors */
	}
done:
	FLUSH();
error:
	return (__sferror(fp) ? EOF : ret);
	/* NOTREACHED */
}

#ifdef FLOATING_POINT

#ifdef _NO_LONGDBL
extern char *_dtoa_r _PARAMS((struct _reent *, double, int,
			      int, int *, int *, char **));
#else
extern char *_ldtoa_r _PARAMS((struct _reent *, _LONG_DOUBLE, int,
			      int, int *, int *, char **));
#undef word0
#define word0(x) ldword0(x)
#endif

static char *
cvt(data, value, ndigits, flags, sign, decpt, ch, length)
	struct _reent *data;
#ifdef _NO_LONGDBL
	double value;
#else
	_LONG_DOUBLE value;
#endif
	int ndigits, flags, *decpt, ch, *length;
	char *sign;
{
	int mode, dsgn;
	char *digits, *bp, *rve;
#ifdef _NO_LONGDBL
        union double_union tmp;
#else
        struct ldieee *ldptr;
#endif

	if (ch == 'f') {
		mode = 3;		/* ndigits after the decimal point */
	} else {
		/* To obtain ndigits after the decimal point for the 'e' 
		 * and 'E' formats, round to ndigits + 1 significant 
		 * figures.
		 */
		if (ch == 'e' || ch == 'E') {
			ndigits++;
		}
		mode = 2;		/* ndigits significant digits */
	}

#ifdef _NO_LONGDBL
        tmp.d = value;

	if (word0(tmp) & Sign_bit) { /* this will check for < 0 and -0.0 */
		value = -value;
		*sign = '-';
        } else
		*sign = '\000';

	digits = _dtoa_r(data, value, mode, ndigits, decpt, &dsgn, &rve);
#else /* !_NO_LONGDBL */
	ldptr = (struct ldieee *)&value;
	if (ldptr->sign) { /* this will check for < 0 and -0.0 */
		value = -value;
		*sign = '-';
        } else
		*sign = '\000';

	digits = _ldtoa_r(data, value, mode, ndigits, decpt, &dsgn, &rve);
#endif /* !_NO_LONGDBL */

	if ((ch != 'g' && ch != 'G') || flags & ALT) {	/* Print trailing zeros */
		bp = digits + ndigits;
		if (ch == 'f') {
			if (*digits == '0' && value)
				*decpt = -ndigits + 1;
			bp += *decpt;
		}
		if (value == 0)	/* kludge for __dtoa irregularity */
			rve = bp;
		while (rve < bp)
			*rve++ = '0';
	}
	*length = rve - digits;
	return (digits);
}

static int
exponent(p0, exp, fmtch)
	char *p0;
	int exp, fmtch;
{
	register char *p, *t;
	char expbuf[40];

	p = p0;
	*p++ = fmtch;
	if (exp < 0) {
		exp = -exp;
		*p++ = '-';
	}
	else
		*p++ = '+';
	t = expbuf + 40;
	if (exp > 9) {
		do {
			*--t = to_char(exp % 10);
		} while ((exp /= 10) > 9);
		*--t = to_char(exp);
		for (; t < expbuf + 40; *p++ = *t++);
	}
	else {
		*p++ = '0';
		*p++ = to_char(exp);
	}
	return (p - p0);
}
#endif /* FLOATING_POINT */

#ifdef __SPE__
extern char *_ufix64toa_r _PARAMS((struct _reent *, unsigned long long, int,
			           int, int *, int *, char **));
static char *
cvt_ufix64 (data, value, ndigits, decpt, length)
	struct _reent *data;
	unsigned long long value;
	int ndigits, *decpt, *length;
{
	int dsgn;
	char *digits, *bp, *rve;

	/* treat the same as %f format and use mode=3 */
	digits = _ufix64toa_r (data, value, 3, ndigits, decpt, &dsgn, &rve);

        /* print trailing zeroes */
	bp = digits + ndigits;
	if (*digits == '0' && value)
	  *decpt = -ndigits + 1;
	bp += *decpt;
	if (value == 0)	/* kludge for __dtoa irregularity */
	  rve = bp;
	while (rve < bp)
	  *rve++ = '0';
	*length = rve - digits;
	return (digits);
}
#endif /* __SPE__ */