1 /* Floating point output for `printf'.
2 Copyright (C) 1995-2003, 2006, 2007, 2008 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5 Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.
7 The GNU C Library is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Lesser General Public
9 License as published by the Free Software Foundation; either
10 version 2.1 of the License, or (at your option) any later version.
12 The GNU C Library is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Lesser General Public License for more details.
17 You should have received a copy of the GNU Lesser General Public
18 License along with the GNU C Library; if not, write to the Free
19 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
22 /* The gmp headers need some configuration frobs. */
29 #include <gmp-mparam.h>
32 #include <stdlib/gmp-impl.h>
33 #include <stdlib/longlong.h>
34 #include <stdlib/fpioconst.h>
35 #include <locale/localeinfo.h>
44 #ifdef COMPILE_WPRINTF
45 # define CHAR_T wchar_t
50 #include "_i18n_number.h"
53 # define NDEBUG /* Undefine this for debugging assertions. */
57 /* This defines make it possible to use the same code for GNU C library and
58 the GNU I/O library. */
59 #define PUT(f, s, n) _IO_sputn (f, s, n)
60 #define PAD(f, c, n) (wide ? _IO_wpadn (f, c, n) : INTUSE(_IO_padn) (f, c, n))
61 /* We use this file GNU C library and GNU I/O library. So make
64 #define putc(c, f) (wide \
65 ? (int)_IO_putwc_unlocked (c, f) : _IO_putc_unlocked (c, f))
66 #define size_t _IO_size_t
69 /* Macros for doing the actual output. */
74 register const int outc = (ch); \
75 if (putc (outc, fp) == EOF) \
77 if (buffer_malloced) \
84 #define PRINT(ptr, wptr, len) \
87 register size_t outlen = (len); \
90 if (PUT (fp, wide ? (const char *) wptr : ptr, outlen) != outlen) \
92 if (buffer_malloced) \
102 while (outlen-- > 0) \
105 while (outlen-- > 0) \
110 #define PADN(ch, len) \
113 if (PAD (fp, ch, len) != len) \
115 if (buffer_malloced) \
123 /* We use the GNU MP library to handle large numbers.
125 An MP variable occupies a varying number of entries in its array. We keep
126 track of this number for efficiency reasons. Otherwise we would always
127 have to process the whole array. */
128 #define MPN_VAR(name) mp_limb_t *name; mp_size_t name##size
130 #define MPN_ASSIGN(dst,src) \
131 memcpy (dst, src, (dst##size = src##size) * sizeof (mp_limb_t))
132 #define MPN_GE(u,v) \
133 (u##size > v##size || (u##size == v##size && __mpn_cmp (u, v, u##size) >= 0))
135 extern int __isinfl_internal (long double) attribute_hidden
;
136 extern int __isnanl_internal (long double) attribute_hidden
;
138 extern mp_size_t
__mpn_extract_double (mp_ptr res_ptr
, mp_size_t size
,
139 int *expt
, int *is_neg
,
141 extern mp_size_t
__mpn_extract_long_double (mp_ptr res_ptr
, mp_size_t size
,
142 int *expt
, int *is_neg
,
144 extern unsigned int __guess_grouping (unsigned int intdig_max
,
145 const char *grouping
);
148 static wchar_t *group_number (wchar_t *buf
, wchar_t *bufend
,
149 unsigned int intdig_no
, const char *grouping
,
150 wchar_t thousands_sep
, int ngroups
)
155 ___printf_fp (FILE *fp
,
156 const struct printf_info
*info
,
157 const void *const *args
)
159 /* The floating-point value to output. */
163 __long_double_t ldbl
;
167 /* Locale-dependent representation of decimal point. */
171 /* Locale-dependent thousands separator and grouping specification. */
172 const char *thousands_sep
= NULL
;
173 wchar_t thousands_sepwc
= 0;
174 const char *grouping
;
176 /* "NaN" or "Inf" for the special cases. */
177 const char *special
= NULL
;
178 const wchar_t *wspecial
= NULL
;
180 /* We need just a few limbs for the input before shifting to the right
182 mp_limb_t fp_input
[(LDBL_MANT_DIG
+ BITS_PER_MP_LIMB
- 1) / BITS_PER_MP_LIMB
];
183 /* We need to shift the contents of fp_input by this amount of bits. */
186 /* The fraction of the floting-point value in question */
188 /* and the exponent. */
190 /* Sign of the exponent. */
192 /* Sign of float number. */
195 /* Scaling factor. */
198 /* Temporary bignum value. */
201 /* Digit which is result of last hack_digit() call. */
204 /* The type of output format that will be used: 'e'/'E' or 'f'. */
207 /* Counter for number of written characters. */
210 /* General helper (carry limb). */
213 /* Nonzero if this is output on a wide character stream. */
214 int wide
= info
->wide
;
216 /* Buffer in which we produce the output. */
217 wchar_t *wbuffer
= NULL
;
218 /* Flag whether wbuffer is malloc'ed or not. */
219 int buffer_malloced
= 0;
221 auto wchar_t hack_digit (void);
223 wchar_t hack_digit (void)
227 if (expsign
!= 0 && type
== 'f' && exponent
-- > 0)
229 else if (scalesize
== 0)
231 hi
= frac
[fracsize
- 1];
232 frac
[fracsize
- 1] = __mpn_mul_1 (frac
, frac
, fracsize
- 1, 10);
236 if (fracsize
< scalesize
)
240 hi
= mpn_divmod (tmp
, frac
, fracsize
, scale
, scalesize
);
241 tmp
[fracsize
- scalesize
] = hi
;
244 fracsize
= scalesize
;
245 while (fracsize
!= 0 && frac
[fracsize
- 1] == 0)
249 /* We're not prepared for an mpn variable with zero
256 mp_limb_t _cy
= __mpn_mul_1 (frac
, frac
, fracsize
, 10);
258 frac
[fracsize
++] = _cy
;
265 /* Figure out the decimal point character. */
266 if (info
->extra
== 0)
268 decimal
= _NL_CURRENT (LC_NUMERIC
, DECIMAL_POINT
);
269 decimalwc
= _NL_CURRENT_WORD (LC_NUMERIC
, _NL_NUMERIC_DECIMAL_POINT_WC
);
273 decimal
= _NL_CURRENT (LC_MONETARY
, MON_DECIMAL_POINT
);
274 if (*decimal
== '\0')
275 decimal
= _NL_CURRENT (LC_NUMERIC
, DECIMAL_POINT
);
276 decimalwc
= _NL_CURRENT_WORD (LC_MONETARY
,
277 _NL_MONETARY_DECIMAL_POINT_WC
);
278 if (decimalwc
== L
'\0')
279 decimalwc
= _NL_CURRENT_WORD (LC_NUMERIC
,
280 _NL_NUMERIC_DECIMAL_POINT_WC
);
282 /* The decimal point character must not be zero. */
283 assert (*decimal
!= '\0');
284 assert (decimalwc
!= L
'\0');
288 if (info
->extra
== 0)
289 grouping
= _NL_CURRENT (LC_NUMERIC
, GROUPING
);
291 grouping
= _NL_CURRENT (LC_MONETARY
, MON_GROUPING
);
293 if (*grouping
<= 0 || *grouping
== CHAR_MAX
)
297 /* Figure out the thousands separator character. */
300 if (info
->extra
== 0)
302 _NL_CURRENT_WORD (LC_NUMERIC
, _NL_NUMERIC_THOUSANDS_SEP_WC
);
305 _NL_CURRENT_WORD (LC_MONETARY
,
306 _NL_MONETARY_THOUSANDS_SEP_WC
);
310 if (info
->extra
== 0)
311 thousands_sep
= _NL_CURRENT (LC_NUMERIC
, THOUSANDS_SEP
);
313 thousands_sep
= _NL_CURRENT (LC_MONETARY
, MON_THOUSANDS_SEP
);
316 if ((wide
&& thousands_sepwc
== L
'\0')
317 || (! wide
&& *thousands_sep
== '\0'))
319 else if (thousands_sepwc
== L
'\0')
320 /* If we are printing multibyte characters and there is a
321 multibyte representation for the thousands separator,
322 we must ensure the wide character thousands separator
323 is available, even if it is fake. */
324 thousands_sepwc
= 0xfffffffe;
330 /* Fetch the argument value. */
331 #ifndef __NO_LONG_DOUBLE_MATH
332 if (info
->is_long_double
&& sizeof (long double) > sizeof (double))
334 fpnum
.ldbl
= *(const long double *) args
[0];
336 /* Check for special values: not a number or infinity. */
337 if (__isnanl (fpnum
.ldbl
))
339 union ieee854_long_double u
= { .d
= fpnum
.ldbl
};
340 is_neg
= u
.ieee
.negative
!= 0;
341 if (isupper (info
->spec
))
352 else if (__isinfl (fpnum
.ldbl
))
354 is_neg
= fpnum
.ldbl
< 0;
355 if (isupper (info
->spec
))
368 fracsize
= __mpn_extract_long_double (fp_input
,
370 sizeof (fp_input
[0])),
373 to_shift
= 1 + fracsize
* BITS_PER_MP_LIMB
- LDBL_MANT_DIG
;
377 #endif /* no long double */
379 fpnum
.dbl
= *(const double *) args
[0];
381 /* Check for special values: not a number or infinity. */
382 if (__isnan (fpnum
.dbl
))
384 union ieee754_double u
= { .d
= fpnum
.dbl
};
385 is_neg
= u
.ieee
.negative
!= 0;
386 if (isupper (info
->spec
))
397 else if (__isinf (fpnum
.dbl
))
399 is_neg
= fpnum
.dbl
< 0;
400 if (isupper (info
->spec
))
413 fracsize
= __mpn_extract_double (fp_input
,
415 / sizeof (fp_input
[0])),
416 &exponent
, &is_neg
, fpnum
.dbl
);
417 to_shift
= 1 + fracsize
* BITS_PER_MP_LIMB
- DBL_MANT_DIG
;
423 int width
= info
->width
;
425 if (is_neg
|| info
->showsign
|| info
->space
)
429 if (!info
->left
&& width
> 0)
434 else if (info
->showsign
)
436 else if (info
->space
)
439 PRINT (special
, wspecial
, 3);
441 if (info
->left
&& width
> 0)
448 /* We need three multiprecision variables. Now that we have the exponent
449 of the number we can allocate the needed memory. It would be more
450 efficient to use variables of the fixed maximum size but because this
451 would be really big it could lead to memory problems. */
453 mp_size_t bignum_size
= ((ABS (exponent
) + BITS_PER_MP_LIMB
- 1)
455 + (LDBL_MANT_DIG
/ BITS_PER_MP_LIMB
> 2 ? 8 : 4))
456 * sizeof (mp_limb_t
);
457 frac
= (mp_limb_t
*) alloca (bignum_size
);
458 tmp
= (mp_limb_t
*) alloca (bignum_size
);
459 scale
= (mp_limb_t
*) alloca (bignum_size
);
462 /* We now have to distinguish between numbers with positive and negative
463 exponents because the method used for the one is not applicable/efficient
470 int explog
= LDBL_MAX_10_EXP_LOG
;
472 const struct mp_power
*powers
= &_fpioconst_pow10
[explog
+ 1];
475 if ((exponent
+ to_shift
) % BITS_PER_MP_LIMB
== 0)
477 MPN_COPY_DECR (frac
+ (exponent
+ to_shift
) / BITS_PER_MP_LIMB
,
479 fracsize
+= (exponent
+ to_shift
) / BITS_PER_MP_LIMB
;
483 cy
= __mpn_lshift (frac
+ (exponent
+ to_shift
) / BITS_PER_MP_LIMB
,
485 (exponent
+ to_shift
) % BITS_PER_MP_LIMB
);
486 fracsize
+= (exponent
+ to_shift
) / BITS_PER_MP_LIMB
;
488 frac
[fracsize
++] = cy
;
490 MPN_ZERO (frac
, (exponent
+ to_shift
) / BITS_PER_MP_LIMB
);
492 assert (powers
> &_fpioconst_pow10
[0]);
497 /* The number of the product of two binary numbers with n and m
498 bits respectively has m+n or m+n-1 bits. */
499 if (exponent
>= scaleexpo
+ powers
->p_expo
- 1)
503 #ifndef __NO_LONG_DOUBLE_MATH
504 if (LDBL_MANT_DIG
> _FPIO_CONST_OFFSET
* BITS_PER_MP_LIMB
505 && info
->is_long_double
)
507 #define _FPIO_CONST_SHIFT \
508 (((LDBL_MANT_DIG + BITS_PER_MP_LIMB - 1) / BITS_PER_MP_LIMB) \
509 - _FPIO_CONST_OFFSET)
510 /* 64bit const offset is not enough for
511 IEEE quad long double. */
512 tmpsize
= powers
->arraysize
+ _FPIO_CONST_SHIFT
;
513 memcpy (tmp
+ _FPIO_CONST_SHIFT
,
514 &__tens
[powers
->arrayoff
],
515 tmpsize
* sizeof (mp_limb_t
));
516 MPN_ZERO (tmp
, _FPIO_CONST_SHIFT
);
517 /* Adjust exponent, as scaleexpo will be this much
519 exponent
+= _FPIO_CONST_SHIFT
* BITS_PER_MP_LIMB
;
524 tmpsize
= powers
->arraysize
;
525 memcpy (tmp
, &__tens
[powers
->arrayoff
],
526 tmpsize
* sizeof (mp_limb_t
));
531 cy
= __mpn_mul (tmp
, scale
, scalesize
,
532 &__tens
[powers
->arrayoff
533 + _FPIO_CONST_OFFSET
],
534 powers
->arraysize
- _FPIO_CONST_OFFSET
);
535 tmpsize
= scalesize
+ powers
->arraysize
- _FPIO_CONST_OFFSET
;
540 if (MPN_GE (frac
, tmp
))
543 MPN_ASSIGN (scale
, tmp
);
544 count_leading_zeros (cnt
, scale
[scalesize
- 1]);
545 scaleexpo
= (scalesize
- 2) * BITS_PER_MP_LIMB
- cnt
- 1;
546 exp10
|= 1 << explog
;
551 while (powers
> &_fpioconst_pow10
[0]);
554 /* Optimize number representations. We want to represent the numbers
555 with the lowest number of bytes possible without losing any
556 bytes. Also the highest bit in the scaling factor has to be set
557 (this is a requirement of the MPN division routines). */
560 /* Determine minimum number of zero bits at the end of
562 for (i
= 0; scale
[i
] == 0 && frac
[i
] == 0; i
++)
565 /* Determine number of bits the scaling factor is misplaced. */
566 count_leading_zeros (cnt_h
, scale
[scalesize
- 1]);
570 /* The highest bit of the scaling factor is already set. So
571 we only have to remove the trailing empty limbs. */
574 MPN_COPY_INCR (scale
, scale
+ i
, scalesize
- i
);
576 MPN_COPY_INCR (frac
, frac
+ i
, fracsize
- i
);
584 count_trailing_zeros (cnt_l
, scale
[i
]);
588 count_trailing_zeros (cnt_l2
, frac
[i
]);
594 count_trailing_zeros (cnt_l
, frac
[i
]);
596 /* Now shift the numbers to their optimal position. */
597 if (i
== 0 && BITS_PER_MP_LIMB
- cnt_h
> cnt_l
)
599 /* We cannot save any memory. So just roll both numbers
600 so that the scaling factor has its highest bit set. */
602 (void) __mpn_lshift (scale
, scale
, scalesize
, cnt_h
);
603 cy
= __mpn_lshift (frac
, frac
, fracsize
, cnt_h
);
605 frac
[fracsize
++] = cy
;
607 else if (BITS_PER_MP_LIMB
- cnt_h
<= cnt_l
)
609 /* We can save memory by removing the trailing zero limbs
610 and by packing the non-zero limbs which gain another
613 (void) __mpn_rshift (scale
, scale
+ i
, scalesize
- i
,
614 BITS_PER_MP_LIMB
- cnt_h
);
616 (void) __mpn_rshift (frac
, frac
+ i
, fracsize
- i
,
617 BITS_PER_MP_LIMB
- cnt_h
);
618 fracsize
-= frac
[fracsize
- i
- 1] == 0 ? i
+ 1 : i
;
622 /* We can only save the memory of the limbs which are zero.
623 The non-zero parts occupy the same number of limbs. */
625 (void) __mpn_rshift (scale
, scale
+ (i
- 1),
627 BITS_PER_MP_LIMB
- cnt_h
);
629 (void) __mpn_rshift (frac
, frac
+ (i
- 1),
631 BITS_PER_MP_LIMB
- cnt_h
);
632 fracsize
-= frac
[fracsize
- (i
- 1) - 1] == 0 ? i
: i
- 1;
637 else if (exponent
< 0)
641 int explog
= LDBL_MAX_10_EXP_LOG
;
642 const struct mp_power
*powers
= &_fpioconst_pow10
[explog
+ 1];
643 mp_size_t used_limbs
= fracsize
- 1;
645 /* Now shift the input value to its right place. */
646 cy
= __mpn_lshift (frac
, fp_input
, fracsize
, to_shift
);
647 frac
[fracsize
++] = cy
;
648 assert (cy
== 1 || (frac
[fracsize
- 2] == 0 && frac
[0] == 0));
651 exponent
= -exponent
;
653 assert (powers
!= &_fpioconst_pow10
[0]);
658 if (exponent
>= powers
->m_expo
)
660 int i
, incr
, cnt_h
, cnt_l
;
663 /* The __mpn_mul function expects the first argument to be
664 bigger than the second. */
665 if (fracsize
< powers
->arraysize
- _FPIO_CONST_OFFSET
)
666 cy
= __mpn_mul (tmp
, &__tens
[powers
->arrayoff
667 + _FPIO_CONST_OFFSET
],
668 powers
->arraysize
- _FPIO_CONST_OFFSET
,
671 cy
= __mpn_mul (tmp
, frac
, fracsize
,
672 &__tens
[powers
->arrayoff
+ _FPIO_CONST_OFFSET
],
673 powers
->arraysize
- _FPIO_CONST_OFFSET
);
674 tmpsize
= fracsize
+ powers
->arraysize
- _FPIO_CONST_OFFSET
;
678 count_leading_zeros (cnt_h
, tmp
[tmpsize
- 1]);
679 incr
= (tmpsize
- fracsize
) * BITS_PER_MP_LIMB
680 + BITS_PER_MP_LIMB
- 1 - cnt_h
;
682 assert (incr
<= powers
->p_expo
);
684 /* If we increased the exponent by exactly 3 we have to test
685 for overflow. This is done by comparing with 10 shifted
686 to the right position. */
687 if (incr
== exponent
+ 3)
689 if (cnt_h
<= BITS_PER_MP_LIMB
- 4)
693 = ((mp_limb_t
) 10) << (BITS_PER_MP_LIMB
- 4 - cnt_h
);
697 topval
[0] = ((mp_limb_t
) 10) << (BITS_PER_MP_LIMB
- 4);
699 (void) __mpn_lshift (topval
, topval
, 2,
700 BITS_PER_MP_LIMB
- cnt_h
);
704 /* We have to be careful when multiplying the last factor.
705 If the result is greater than 1.0 be have to test it
706 against 10.0. If it is greater or equal to 10.0 the
707 multiplication was not valid. This is because we cannot
708 determine the number of bits in the result in advance. */
709 if (incr
< exponent
+ 3
710 || (incr
== exponent
+ 3 &&
711 (tmp
[tmpsize
- 1] < topval
[1]
712 || (tmp
[tmpsize
- 1] == topval
[1]
713 && tmp
[tmpsize
- 2] < topval
[0]))))
715 /* The factor is right. Adapt binary and decimal
718 exp10
|= 1 << explog
;
720 /* If this factor yields a number greater or equal to
721 1.0, we must not shift the non-fractional digits down. */
725 /* Now we optimize the number representation. */
726 for (i
= 0; tmp
[i
] == 0; ++i
);
727 if (cnt_h
== BITS_PER_MP_LIMB
- 1)
729 MPN_COPY (frac
, tmp
+ i
, tmpsize
- i
);
730 fracsize
= tmpsize
- i
;
734 count_trailing_zeros (cnt_l
, tmp
[i
]);
736 /* Now shift the numbers to their optimal position. */
737 if (i
== 0 && BITS_PER_MP_LIMB
- 1 - cnt_h
> cnt_l
)
739 /* We cannot save any memory. Just roll the
740 number so that the leading digit is in a
743 cy
= __mpn_lshift (frac
, tmp
, tmpsize
, cnt_h
+ 1);
744 fracsize
= tmpsize
+ 1;
745 frac
[fracsize
- 1] = cy
;
747 else if (BITS_PER_MP_LIMB
- 1 - cnt_h
<= cnt_l
)
749 (void) __mpn_rshift (frac
, tmp
+ i
, tmpsize
- i
,
750 BITS_PER_MP_LIMB
- 1 - cnt_h
);
751 fracsize
= tmpsize
- i
;
755 /* We can only save the memory of the limbs which
756 are zero. The non-zero parts occupy the same
759 (void) __mpn_rshift (frac
, tmp
+ (i
- 1),
761 BITS_PER_MP_LIMB
- 1 - cnt_h
);
762 fracsize
= tmpsize
- (i
- 1);
765 used_limbs
= fracsize
- 1;
770 while (powers
!= &_fpioconst_pow10
[1] && exponent
> 0);
771 /* All factors but 10^-1 are tested now. */
776 cy
= __mpn_mul_1 (tmp
, frac
, fracsize
, 10);
778 assert (cy
== 0 || tmp
[tmpsize
- 1] < 20);
780 count_trailing_zeros (cnt_l
, tmp
[0]);
781 if (cnt_l
< MIN (4, exponent
))
783 cy
= __mpn_lshift (frac
, tmp
, tmpsize
,
784 BITS_PER_MP_LIMB
- MIN (4, exponent
));
786 frac
[tmpsize
++] = cy
;
789 (void) __mpn_rshift (frac
, tmp
, tmpsize
, MIN (4, exponent
));
792 assert (frac
[fracsize
- 1] < 10);
798 /* This is a special case. We don't need a factor because the
799 numbers are in the range of 1.0 <= |fp| < 8.0. We simply
800 shift it to the right place and divide it by 1.0 to get the
801 leading digit. (Of course this division is not really made.) */
802 assert (0 <= exponent
&& exponent
< 3 &&
803 exponent
+ to_shift
< BITS_PER_MP_LIMB
);
805 /* Now shift the input value to its right place. */
806 cy
= __mpn_lshift (frac
, fp_input
, fracsize
, (exponent
+ to_shift
));
807 frac
[fracsize
++] = cy
;
812 int width
= info
->width
;
813 wchar_t *wstartp
, *wcp
;
816 int intdig_max
, intdig_no
= 0;
822 char spec
= _tolower (info
->spec
);
828 fracdig_min
= fracdig_max
= info
->prec
< 0 ? 6 : info
->prec
;
829 chars_needed
= 1 + 1 + (size_t) fracdig_max
+ 1 + 1 + 4;
830 /* d . ddd e +- ddd */
831 dig_max
= INT_MAX
; /* Unlimited. */
832 significant
= 1; /* Does not matter here. */
834 else if (spec
== 'f')
837 fracdig_min
= fracdig_max
= info
->prec
< 0 ? 6 : info
->prec
;
838 dig_max
= INT_MAX
; /* Unlimited. */
839 significant
= 1; /* Does not matter here. */
842 intdig_max
= exponent
+ 1;
843 /* This can be really big! */ /* XXX Maybe malloc if too big? */
844 chars_needed
= (size_t) exponent
+ 1 + 1 + (size_t) fracdig_max
;
849 chars_needed
= 1 + 1 + (size_t) fracdig_max
;
854 dig_max
= info
->prec
< 0 ? 6 : (info
->prec
== 0 ? 1 : info
->prec
);
855 if ((expsign
== 0 && exponent
>= dig_max
)
856 || (expsign
!= 0 && exponent
> 4))
858 if ('g' - 'G' == 'e' - 'E')
859 type
= 'E' + (info
->spec
- 'G');
861 type
= isupper (info
->spec
) ? 'E' : 'e';
862 fracdig_max
= dig_max
- 1;
864 chars_needed
= 1 + 1 + (size_t) fracdig_max
+ 1 + 1 + 4;
869 intdig_max
= expsign
== 0 ? exponent
+ 1 : 0;
870 fracdig_max
= dig_max
- intdig_max
;
871 /* We need space for the significant digits and perhaps
872 for leading zeros when < 1.0. The number of leading
873 zeros can be as many as would be required for
874 exponential notation with a negative two-digit
875 exponent, which is 4. */
876 chars_needed
= (size_t) dig_max
+ 1 + 4;
878 fracdig_min
= info
->alt
? fracdig_max
: 0;
879 significant
= 0; /* We count significant digits. */
884 /* Guess the number of groups we will make, and thus how
885 many spaces we need for separator characters. */
886 ngroups
= __guess_grouping (intdig_max
, grouping
);
887 chars_needed
+= ngroups
;
890 /* Allocate buffer for output. We need two more because while rounding
891 it is possible that we need two more characters in front of all the
892 other output. If the amount of memory we have to allocate is too
893 large use `malloc' instead of `alloca'. */
894 size_t wbuffer_to_alloc
= (2 + (size_t) chars_needed
) * sizeof (wchar_t);
895 buffer_malloced
= ! __libc_use_alloca (chars_needed
* 2 * sizeof (wchar_t));
896 if (__builtin_expect (buffer_malloced
, 0))
898 wbuffer
= (wchar_t *) malloc (wbuffer_to_alloc
);
900 /* Signal an error to the caller. */
904 wbuffer
= (wchar_t *) alloca (wbuffer_to_alloc
);
905 wcp
= wstartp
= wbuffer
+ 2; /* Let room for rounding. */
907 /* Do the real work: put digits in allocated buffer. */
908 if (expsign
== 0 || type
!= 'f')
910 assert (expsign
== 0 || intdig_max
== 1);
911 while (intdig_no
< intdig_max
)
914 *wcp
++ = hack_digit ();
919 || (fracdig_max
> 0 && (fracsize
> 1 || frac
[0] != 0)))
924 /* |fp| < 1.0 and the selected type is 'f', so put "0."
931 /* Generate the needed number of fractional digits. */
934 while (fracdig_no
< fracdig_min
+ added_zeros
935 || (fracdig_no
< fracdig_max
&& (fracsize
> 1 || frac
[0] != 0)))
938 *wcp
= hack_digit ();
941 else if (significant
== 0)
950 digit
= hack_digit ();
956 && ((*(wcp
- 1) != decimalwc
&& (*(wcp
- 1) & 1) == 0)
957 || ((*(wcp
- 1) == decimalwc
&& (*(wcp
- 2) & 1) == 0))))
959 /* This is the critical case. */
960 if (fracsize
== 1 && frac
[0] == 0)
961 /* Rest of the number is zero -> round to even.
962 (IEEE 754-1985 4.1 says this is the default rounding.) */
964 else if (scalesize
== 0)
966 /* Here we have to see whether all limbs are zero since no
967 normalization happened. */
968 size_t lcnt
= fracsize
;
969 while (lcnt
>= 1 && frac
[lcnt
- 1] == 0)
972 /* Rest of the number is zero -> round to even.
973 (IEEE 754-1985 4.1 says this is the default rounding.) */
980 /* Process fractional digits. Terminate if not rounded or
981 radix character is reached. */
983 while (*--wtp
!= decimalwc
&& *wtp
== L
'9')
988 if (removed
== fracdig_min
&& added_zeros
> 0)
990 if (*wtp
!= decimalwc
)
993 else if (__builtin_expect (spec
== 'g' && type
== 'f' && info
->alt
994 && wtp
== wstartp
+ 1
995 && wstartp
[0] == L
'0',
997 /* This is a special case: the rounded number is 1.0,
998 the format is 'g' or 'G', and the alternative format
999 is selected. This means the result must be "1.". */
1003 if (fracdig_no
== 0 || *wtp
== decimalwc
)
1005 /* Round the integer digits. */
1006 if (*(wtp
- 1) == decimalwc
)
1009 while (--wtp
>= wstartp
&& *wtp
== L
'9')
1016 /* It is more critical. All digits were 9's. */
1021 exponent
+= expsign
== 0 ? 1 : -1;
1023 /* The above exponent adjustment could lead to 1.0e-00,
1024 e.g. for 0.999999999. Make sure exponent 0 always
1029 else if (intdig_no
== dig_max
)
1031 /* This is the case where for type %g the number fits
1032 really in the range for %f output but after rounding
1033 the number of digits is too big. */
1034 *--wstartp
= decimalwc
;
1037 if (info
->alt
|| fracdig_no
> 0)
1039 /* Overwrite the old radix character. */
1040 wstartp
[intdig_no
+ 2] = L
'0';
1044 fracdig_no
+= intdig_no
;
1046 fracdig_max
= intdig_max
- intdig_no
;
1048 /* Now we must print the exponent. */
1049 type
= isupper (info
->spec
) ? 'E' : 'e';
1053 /* We can simply add another another digit before the
1059 /* While rounding the number of digits can change.
1060 If the number now exceeds the limits remove some
1061 fractional digits. */
1062 if (intdig_no
+ fracdig_no
> dig_max
)
1064 wcp
-= intdig_no
+ fracdig_no
- dig_max
;
1065 fracdig_no
-= intdig_no
+ fracdig_no
- dig_max
;
1072 /* Now remove unnecessary '0' at the end of the string. */
1073 while (fracdig_no
> fracdig_min
+ added_zeros
&& *(wcp
- 1) == L
'0')
1078 /* If we eliminate all fractional digits we perhaps also can remove
1079 the radix character. */
1080 if (fracdig_no
== 0 && !info
->alt
&& *(wcp
- 1) == decimalwc
)
1084 /* Add in separator characters, overwriting the same buffer. */
1085 wcp
= group_number (wstartp
, wcp
, intdig_no
, grouping
, thousands_sepwc
,
1088 /* Write the exponent if it is needed. */
1091 if (__builtin_expect (expsign
!= 0 && exponent
== 4 && spec
== 'g', 0))
1093 /* This is another special case. The exponent of the number is
1094 really smaller than -4, which requires the 'e'/'E' format.
1095 But after rounding the number has an exponent of -4. */
1096 assert (wcp
>= wstartp
+ 1);
1097 assert (wstartp
[0] == L
'1');
1098 __wmemcpy (wstartp
, L
"0.0001", 6);
1099 wstartp
[1] = decimalwc
;
1100 if (wcp
>= wstartp
+ 2)
1102 wmemset (wstartp
+ 6, L
'0', wcp
- (wstartp
+ 2));
1110 *wcp
++ = (wchar_t) type
;
1111 *wcp
++ = expsign
? L
'-' : L
'+';
1113 /* Find the magnitude of the exponent. */
1115 while (expscale
<= exponent
)
1119 /* Exponent always has at least two digits. */
1125 *wcp
++ = L
'0' + (exponent
/ expscale
);
1126 exponent
%= expscale
;
1128 while (expscale
> 10);
1129 *wcp
++ = L
'0' + exponent
;
1133 /* Compute number of characters which must be filled with the padding
1135 if (is_neg
|| info
->showsign
|| info
->space
)
1137 width
-= wcp
- wstartp
;
1139 if (!info
->left
&& info
->pad
!= '0' && width
> 0)
1140 PADN (info
->pad
, width
);
1144 else if (info
->showsign
)
1146 else if (info
->space
)
1149 if (!info
->left
&& info
->pad
== '0' && width
> 0)
1153 char *buffer
= NULL
;
1154 char *buffer_end
= NULL
;
1160 /* Create the single byte string. */
1162 size_t thousands_sep_len
;
1164 size_t factor
= (info
->i18n
1165 ? _NL_CURRENT_WORD (LC_CTYPE
, _NL_CTYPE_MB_CUR_MAX
)
1168 decimal_len
= strlen (decimal
);
1170 if (thousands_sep
== NULL
)
1171 thousands_sep_len
= 0;
1173 thousands_sep_len
= strlen (thousands_sep
);
1175 size_t nbuffer
= (2 + chars_needed
* factor
+ decimal_len
1176 + ngroups
* thousands_sep_len
);
1177 if (__builtin_expect (buffer_malloced
, 0))
1179 buffer
= (char *) malloc (nbuffer
);
1182 /* Signal an error to the caller. */
1188 buffer
= (char *) alloca (nbuffer
);
1189 buffer_end
= buffer
+ nbuffer
;
1191 /* Now copy the wide character string. Since the character
1192 (except for the decimal point and thousands separator) must
1193 be coming from the ASCII range we can esily convert the
1194 string without mapping tables. */
1195 for (cp
= buffer
, copywc
= wstartp
; copywc
< wcp
; ++copywc
)
1196 if (*copywc
== decimalwc
)
1197 cp
= (char *) __mempcpy (cp
, decimal
, decimal_len
);
1198 else if (*copywc
== thousands_sepwc
)
1199 cp
= (char *) __mempcpy (cp
, thousands_sep
, thousands_sep_len
);
1201 *cp
++ = (char) *copywc
;
1205 if (__builtin_expect (info
->i18n
, 0))
1207 #ifdef COMPILE_WPRINTF
1208 wstartp
= _i18n_number_rewrite (wstartp
, wcp
,
1209 wbuffer
+ wbuffer_to_alloc
);
1210 wcp
= wbuffer
+ wbuffer_to_alloc
;
1211 assert ((uintptr_t) wbuffer
<= (uintptr_t) wstartp
);
1212 assert ((uintptr_t) wstartp
1213 < (uintptr_t) wbuffer
+ wbuffer_to_alloc
);
1215 tmpptr
= _i18n_number_rewrite (tmpptr
, cp
, buffer_end
);
1217 assert ((uintptr_t) buffer
<= (uintptr_t) tmpptr
);
1218 assert ((uintptr_t) tmpptr
< (uintptr_t) buffer_end
);
1222 PRINT (tmpptr
, wstartp
, wide
? wcp
- wstartp
: cp
- tmpptr
);
1224 /* Free the memory if necessary. */
1225 if (__builtin_expect (buffer_malloced
, 0))
1232 if (info
->left
&& width
> 0)
1233 PADN (info
->pad
, width
);
1237 ldbl_hidden_def (___printf_fp
, __printf_fp
)
1238 ldbl_strong_alias (___printf_fp
, __printf_fp
)
1240 /* Return the number of extra grouping characters that will be inserted
1241 into a number with INTDIG_MAX integer digits. */
1244 __guess_grouping (unsigned int intdig_max
, const char *grouping
)
1246 unsigned int groups
;
1248 /* We treat all negative values like CHAR_MAX. */
1250 if (*grouping
== CHAR_MAX
|| *grouping
<= 0)
1251 /* No grouping should be done. */
1255 while (intdig_max
> (unsigned int) *grouping
)
1258 intdig_max
-= *grouping
++;
1260 if (*grouping
== CHAR_MAX
1265 /* No more grouping should be done. */
1267 else if (*grouping
== 0)
1269 /* Same grouping repeats. */
1270 groups
+= (intdig_max
- 1) / grouping
[-1];
1278 /* Group the INTDIG_NO integer digits of the number in [BUF,BUFEND).
1279 There is guaranteed enough space past BUFEND to extend it.
1280 Return the new end of buffer. */
1284 group_number (wchar_t *buf
, wchar_t *bufend
, unsigned int intdig_no
,
1285 const char *grouping
, wchar_t thousands_sep
, int ngroups
)
1292 /* Move the fractional part down. */
1293 __wmemmove (buf
+ intdig_no
+ ngroups
, buf
+ intdig_no
,
1294 bufend
- (buf
+ intdig_no
));
1296 p
= buf
+ intdig_no
+ ngroups
- 1;
1299 unsigned int len
= *grouping
++;
1301 *p
-- = buf
[--intdig_no
];
1303 *p
-- = thousands_sep
;
1305 if (*grouping
== CHAR_MAX
1310 /* No more grouping should be done. */
1312 else if (*grouping
== 0)
1313 /* Same grouping repeats. */
1315 } while (intdig_no
> (unsigned int) *grouping
);
1317 /* Copy the remaining ungrouped digits. */
1319 *p
-- = buf
[--intdig_no
];
1322 return bufend
+ ngroups
;