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1 /* Floating point output for `printf'.
2 Copyright (C) 1995, 1996 Free Software Foundation, Inc.
3 Written by Ulrich Drepper.
5 This file is part of the GNU C Library.
7 The GNU C Library is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Library General Public License as
9 published by the Free Software Foundation; either version 2 of the
10 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 Library General Public License for more details.
17 You should have received a copy of the GNU Library General Public
18 License along with the GNU C Library; see the file COPYING.LIB. If
19 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
20 Cambridge, MA 02139, USA. */
22 /* The gmp headers need some configuration frobs. */
33 #include <gmp-mparam.h>
34 #include "../stdlib/gmp.h"
35 #include "../stdlib/gmp-impl.h"
36 #include "../stdlib/longlong.h"
37 #include "../stdlib/fpioconst.h"
38 #include "../locale/localeinfo.h"
46 #define NDEBUG /* Undefine this for debugging assertions. */
49 /* This defines make it possible to use the same code for GNU C library and
50 the GNU I/O library. */
52 # define PUT(f, s, n) _IO_sputn (f, s, n)
53 # define PAD(f, c, n) _IO_padn (f, c, n)
54 /* We use this file GNU C library and GNU I/O library. So make
57 # define putc(c, f) _IO_putc (c, f)
58 # define size_t _IO_size_t
59 # define FILE _IO_FILE
60 #else /* ! USE_IN_LIBIO */
61 # define PUT(f, s, n) fwrite (s, 1, n, f)
62 # define PAD(f, c, n) __printf_pad (f, c, n)
63 ssize_t __printf_pad
__P ((FILE *, char pad
, int n
)); /* In vfprintf.c. */
64 #endif /* USE_IN_LIBIO */
66 /* Macros for doing the actual output. */
71 register const int outc = (ch); \
72 if (putc (outc, fp) == EOF) \
77 #define PRINT(ptr, len) \
80 register size_t outlen = (len); \
83 if (PUT (fp, ptr, outlen) != outlen) \
90 while (outlen-- > 0) \
95 #define PADN(ch, len) \
98 if (PAD (fp, ch, len) != len) \
104 /* We use the GNU MP library to handle large numbers.
106 An MP variable occupies a varying number of entries in its array. We keep
107 track of this number for efficiency reasons. Otherwise we would always
108 have to process the whole array. */
109 #define MPN_VAR(name) mp_limb_t *name; mp_size_t name##size
111 #define MPN_ASSIGN(dst,src) \
112 memcpy (dst, src, (dst##size = src##size) * sizeof (mp_limb_t))
113 #define MPN_GE(u,v) \
114 (u##size > v##size || (u##size == v##size && __mpn_cmp (u, v, u##size) >= 0))
116 extern int __isinfl (long double), __isnanl (long double);
118 extern mp_size_t
__mpn_extract_double (mp_ptr res_ptr
, mp_size_t size
,
119 int *expt
, int *is_neg
,
121 extern mp_size_t
__mpn_extract_long_double (mp_ptr res_ptr
, mp_size_t size
,
122 int *expt
, int *is_neg
,
126 static unsigned int guess_grouping (unsigned int intdig_max
,
127 const char *grouping
, wchar_t sepchar
);
128 static char *group_number (char *buf
, char *bufend
, unsigned int intdig_no
,
129 const char *grouping
, wchar_t thousands_sep
);
133 __printf_fp (FILE *fp
,
134 const struct printf_info
*info
,
135 const void *const *args
)
137 /* The floating-point value to output. */
141 __long_double_t ldbl
;
145 /* Locale-dependent representation of decimal point. */
148 /* Locale-dependent thousands separator and grouping specification. */
149 wchar_t thousands_sep
;
150 const char *grouping
;
152 /* "NaN" or "Inf" for the special cases. */
153 const char *special
= NULL
;
155 /* We need just a few limbs for the input before shifting to the right
157 mp_limb_t fp_input
[(LDBL_MANT_DIG
+ BITS_PER_MP_LIMB
- 1) / BITS_PER_MP_LIMB
];
158 /* We need to shift the contents of fp_input by this amount of bits. */
161 /* The significant of the floting-point value in question */
163 /* and the exponent. */
165 /* Sign of the exponent. */
167 /* Sign of float number. */
170 /* Scaling factor. */
173 /* Temporary bignum value. */
176 /* Digit which is result of last hack_digit() call. */
179 /* The type of output format that will be used: 'e'/'E' or 'f'. */
182 /* Counter for number of written characters. */
185 /* General helper (carry limb). */
188 char hack_digit (void)
192 if (expsign
!= 0 && type
== 'f' && exponent
-- > 0)
194 else if (scalesize
== 0)
196 hi
= frac
[fracsize
- 1];
197 cy
= __mpn_mul_1 (frac
, frac
, fracsize
- 1, 10);
198 frac
[fracsize
- 1] = cy
;
202 if (fracsize
< scalesize
)
206 hi
= mpn_divmod (tmp
, frac
, fracsize
, scale
, scalesize
);
207 tmp
[fracsize
- scalesize
] = hi
;
210 fracsize
= scalesize
;
211 while (fracsize
!= 0 && frac
[fracsize
- 1] == 0)
215 /* We're not prepared for an mpn variable with zero
222 cy
= __mpn_mul_1 (frac
, frac
, fracsize
, 10);
224 frac
[fracsize
++] = cy
;
231 /* Figure out the decimal point character. */
232 if (mbtowc (&decimal
, _NL_CURRENT (LC_NUMERIC
, DECIMAL_POINT
),
233 strlen (_NL_CURRENT (LC_NUMERIC
, DECIMAL_POINT
))) <= 0)
234 decimal
= (wchar_t) *_NL_CURRENT (LC_NUMERIC
, DECIMAL_POINT
);
239 grouping
= _NL_CURRENT (LC_NUMERIC
, GROUPING
);
240 if (*grouping
<= 0 || *grouping
== CHAR_MAX
)
244 /* Figure out the thousands seperator character. */
245 if (mbtowc (&thousands_sep
, _NL_CURRENT (LC_NUMERIC
, THOUSANDS_SEP
),
246 strlen (_NL_CURRENT (LC_NUMERIC
, THOUSANDS_SEP
))) <= 0)
247 thousands_sep
= (wchar_t) *_NL_CURRENT (LC_NUMERIC
, THOUSANDS_SEP
);
248 if (thousands_sep
== L
'\0')
255 /* Fetch the argument value. */
256 if (info
->is_long_double
&& sizeof (long double) > sizeof (double))
258 fpnum
.ldbl
= *(const long double *) args
[0];
260 /* Check for special values: not a number or infinity. */
261 if (__isnanl (fpnum
.ldbl
))
266 else if (__isinfl (fpnum
.ldbl
))
269 is_neg
= fpnum
.ldbl
< 0;
273 fracsize
= __mpn_extract_long_double (fp_input
,
275 sizeof (fp_input
[0])),
278 to_shift
= 1 + fracsize
* BITS_PER_MP_LIMB
- LDBL_MANT_DIG
;
283 fpnum
.dbl
= *(const double *) args
[0];
285 /* Check for special values: not a number or infinity. */
286 if (__isnan (fpnum
.dbl
))
291 else if (__isinf (fpnum
.dbl
))
294 is_neg
= fpnum
.dbl
< 0;
298 fracsize
= __mpn_extract_double (fp_input
,
300 / sizeof (fp_input
[0])),
301 &exponent
, &is_neg
, fpnum
.dbl
);
302 to_shift
= 1 + fracsize
* BITS_PER_MP_LIMB
- DBL_MANT_DIG
;
308 int width
= info
->prec
> info
->width
? info
->prec
: info
->width
;
310 if (is_neg
|| info
->showsign
|| info
->space
)
314 if (!info
->left
&& width
> 0)
319 else if (info
->showsign
)
321 else if (info
->space
)
326 if (info
->left
&& width
> 0)
333 /* We need three multiprecision variables. Now that we have the exponent
334 of the number we can allocate the needed memory. It would be more
335 efficient to use variables of the fixed maximum size but because this
336 would be really big it could lead to memory problems. */
338 mp_size_t bignum_size
= ((ABS (exponent
) + BITS_PER_MP_LIMB
- 1)
339 / BITS_PER_MP_LIMB
+ 4) * sizeof (mp_limb_t
);
340 frac
= (mp_limb_t
*) alloca (bignum_size
);
341 tmp
= (mp_limb_t
*) alloca (bignum_size
);
342 scale
= (mp_limb_t
*) alloca (bignum_size
);
345 /* We now have to distinguish between numbers with positive and negative
346 exponents because the method used for the one is not applicable/efficient
353 int explog
= LDBL_MAX_10_EXP_LOG
;
355 const struct mp_power
*tens
= &_fpioconst_pow10
[explog
+ 1];
358 if ((exponent
+ to_shift
) % BITS_PER_MP_LIMB
== 0)
360 MPN_COPY_DECR (frac
+ (exponent
+ to_shift
) / BITS_PER_MP_LIMB
,
362 fracsize
+= (exponent
+ to_shift
) / BITS_PER_MP_LIMB
;
366 cy
= __mpn_lshift (frac
+ (exponent
+ to_shift
) / BITS_PER_MP_LIMB
,
368 (exponent
+ to_shift
) % BITS_PER_MP_LIMB
);
369 fracsize
+= (exponent
+ to_shift
) / BITS_PER_MP_LIMB
;
371 frac
[fracsize
++] = cy
;
373 MPN_ZERO (frac
, (exponent
+ to_shift
) / BITS_PER_MP_LIMB
);
375 assert (tens
> &_fpioconst_pow10
[0]);
380 /* The number of the product of two binary numbers with n and m
381 bits respectively has m+n or m+n-1 bits. */
382 if (exponent
>= scaleexpo
+ tens
->p_expo
- 1)
385 MPN_ASSIGN (tmp
, tens
->array
);
388 cy
= __mpn_mul (tmp
, scale
, scalesize
,
389 &tens
->array
[_FPIO_CONST_OFFSET
],
390 tens
->arraysize
- _FPIO_CONST_OFFSET
);
391 tmpsize
= scalesize
+ tens
->arraysize
- _FPIO_CONST_OFFSET
;
396 if (MPN_GE (frac
, tmp
))
399 MPN_ASSIGN (scale
, tmp
);
400 count_leading_zeros (cnt
, scale
[scalesize
- 1]);
401 scaleexpo
= (scalesize
- 2) * BITS_PER_MP_LIMB
- cnt
- 1;
402 exp10
|= 1 << explog
;
407 while (tens
> &_fpioconst_pow10
[0]);
410 /* Optimize number representations. We want to represent the numbers
411 with the lowest number of bytes possible without losing any
412 bytes. Also the highest bit in the scaling factor has to be set
413 (this is a requirement of the MPN division routines). */
416 /* Determine minimum number of zero bits at the end of
418 for (i
= 0; scale
[i
] == 0 && frac
[i
] == 0; i
++)
421 /* Determine number of bits the scaling factor is misplaced. */
422 count_leading_zeros (cnt_h
, scale
[scalesize
- 1]);
426 /* The highest bit of the scaling factor is already set. So
427 we only have to remove the trailing empty limbs. */
430 MPN_COPY_INCR (scale
, scale
+ i
, scalesize
- i
);
432 MPN_COPY_INCR (frac
, frac
+ i
, fracsize
- i
);
440 count_trailing_zeros (cnt_l
, scale
[i
]);
444 count_trailing_zeros (cnt_l2
, frac
[i
]);
450 count_trailing_zeros (cnt_l
, frac
[i
]);
452 /* Now shift the numbers to their optimal position. */
453 if (i
== 0 && BITS_PER_MP_LIMB
- cnt_h
> cnt_l
)
455 /* We cannot save any memory. So just roll both numbers
456 so that the scaling factor has its highest bit set. */
458 (void) __mpn_lshift (scale
, scale
, scalesize
, cnt_h
);
459 cy
= __mpn_lshift (frac
, frac
, fracsize
, cnt_h
);
461 frac
[fracsize
++] = cy
;
463 else if (BITS_PER_MP_LIMB
- cnt_h
<= cnt_l
)
465 /* We can save memory by removing the trailing zero limbs
466 and by packing the non-zero limbs which gain another
469 (void) __mpn_rshift (scale
, scale
+ i
, scalesize
- i
,
470 BITS_PER_MP_LIMB
- cnt_h
);
472 (void) __mpn_rshift (frac
, frac
+ i
, fracsize
- i
,
473 BITS_PER_MP_LIMB
- cnt_h
);
474 fracsize
-= frac
[fracsize
- i
- 1] == 0 ? i
+ 1 : i
;
478 /* We can only save the memory of the limbs which are zero.
479 The non-zero parts occupy the same number of limbs. */
481 (void) __mpn_rshift (scale
, scale
+ (i
- 1),
483 BITS_PER_MP_LIMB
- cnt_h
);
485 (void) __mpn_rshift (frac
, frac
+ (i
- 1),
487 BITS_PER_MP_LIMB
- cnt_h
);
488 fracsize
-= frac
[fracsize
- (i
- 1) - 1] == 0 ? i
: i
- 1;
493 else if (exponent
< 0)
497 int explog
= LDBL_MAX_10_EXP_LOG
;
498 const struct mp_power
*tens
= &_fpioconst_pow10
[explog
+ 1];
499 mp_size_t used_limbs
= fracsize
- 1;
501 /* Now shift the input value to its right place. */
502 cy
= __mpn_lshift (frac
, fp_input
, fracsize
, to_shift
);
503 frac
[fracsize
++] = cy
;
504 assert (cy
== 1 || (frac
[fracsize
- 2] == 0 && frac
[0] == 0));
507 exponent
= -exponent
;
509 assert (tens
!= &_fpioconst_pow10
[0]);
514 if (exponent
>= tens
->m_expo
)
516 int i
, incr
, cnt_h
, cnt_l
;
519 /* The __mpn_mul function expects the first argument to be
520 bigger than the second. */
521 if (fracsize
< tens
->arraysize
- _FPIO_CONST_OFFSET
)
522 cy
= __mpn_mul (tmp
, &tens
->array
[_FPIO_CONST_OFFSET
],
523 tens
->arraysize
- _FPIO_CONST_OFFSET
,
526 cy
= __mpn_mul (tmp
, frac
, fracsize
,
527 &tens
->array
[_FPIO_CONST_OFFSET
],
528 tens
->arraysize
- _FPIO_CONST_OFFSET
);
529 tmpsize
= fracsize
+ tens
->arraysize
- _FPIO_CONST_OFFSET
;
533 count_leading_zeros (cnt_h
, tmp
[tmpsize
- 1]);
534 incr
= (tmpsize
- fracsize
) * BITS_PER_MP_LIMB
535 + BITS_PER_MP_LIMB
- 1 - cnt_h
;
537 assert (incr
<= tens
->p_expo
);
539 /* If we increased the exponent by exactly 3 we have to test
540 for overflow. This is done by comparing with 10 shifted
541 to the right position. */
542 if (incr
== exponent
+ 3)
543 if (cnt_h
<= BITS_PER_MP_LIMB
- 4)
547 = ((mp_limb_t
) 10) << (BITS_PER_MP_LIMB
- 4 - cnt_h
);
551 topval
[0] = ((mp_limb_t
) 10) << (BITS_PER_MP_LIMB
- 4);
553 (void) __mpn_lshift (topval
, topval
, 2,
554 BITS_PER_MP_LIMB
- cnt_h
);
557 /* We have to be careful when multiplying the last factor.
558 If the result is greater than 1.0 be have to test it
559 against 10.0. If it is greater or equal to 10.0 the
560 multiplication was not valid. This is because we cannot
561 determine the number of bits in the result in advance. */
562 if (incr
< exponent
+ 3
563 || (incr
== exponent
+ 3 &&
564 (tmp
[tmpsize
- 1] < topval
[1]
565 || (tmp
[tmpsize
- 1] == topval
[1]
566 && tmp
[tmpsize
- 2] < topval
[0]))))
568 /* The factor is right. Adapt binary and decimal
571 exp10
|= 1 << explog
;
573 /* If this factor yields a number greater or equal to
574 1.0, we must not shift the non-fractional digits down. */
578 /* Now we optimize the number representation. */
579 for (i
= 0; tmp
[i
] == 0; ++i
);
580 if (cnt_h
== BITS_PER_MP_LIMB
- 1)
582 MPN_COPY (frac
, tmp
+ i
, tmpsize
- i
);
583 fracsize
= tmpsize
- i
;
587 count_trailing_zeros (cnt_l
, tmp
[i
]);
589 /* Now shift the numbers to their optimal position. */
590 if (i
== 0 && BITS_PER_MP_LIMB
- 1 - cnt_h
> cnt_l
)
592 /* We cannot save any memory. Just roll the
593 number so that the leading digit is in a
596 cy
= __mpn_lshift (frac
, tmp
, tmpsize
, cnt_h
+ 1);
597 fracsize
= tmpsize
+ 1;
598 frac
[fracsize
- 1] = cy
;
600 else if (BITS_PER_MP_LIMB
- 1 - cnt_h
<= cnt_l
)
602 (void) __mpn_rshift (frac
, tmp
+ i
, tmpsize
- i
,
603 BITS_PER_MP_LIMB
- 1 - cnt_h
);
604 fracsize
= tmpsize
- i
;
608 /* We can only save the memory of the limbs which
609 are zero. The non-zero parts occupy the same
612 (void) __mpn_rshift (frac
, tmp
+ (i
- 1),
614 BITS_PER_MP_LIMB
- 1 - cnt_h
);
615 fracsize
= tmpsize
- (i
- 1);
618 used_limbs
= fracsize
- 1;
623 while (tens
!= &_fpioconst_pow10
[1] && exponent
> 0);
624 /* All factors but 10^-1 are tested now. */
629 cy
= __mpn_mul_1 (tmp
, frac
, fracsize
, 10);
631 assert (cy
== 0 || tmp
[tmpsize
- 1] < 20);
633 count_trailing_zeros (cnt_l
, tmp
[0]);
634 if (cnt_l
< MIN (4, exponent
))
636 cy
= __mpn_lshift (frac
, tmp
, tmpsize
,
637 BITS_PER_MP_LIMB
- MIN (4, exponent
));
639 frac
[tmpsize
++] = cy
;
642 (void) __mpn_rshift (frac
, tmp
, tmpsize
, MIN (4, exponent
));
645 assert (frac
[fracsize
- 1] < 10);
651 /* This is a special case. We don't need a factor because the
652 numbers are in the range of 0.0 <= fp < 8.0. We simply
653 shift it to the right place and divide it by 1.0 to get the
654 leading digit. (Of course this division is not really made.) */
655 assert (0 <= exponent
&& exponent
< 3 &&
656 exponent
+ to_shift
< BITS_PER_MP_LIMB
);
658 /* Now shift the input value to its right place. */
659 cy
= __mpn_lshift (frac
, fp_input
, fracsize
, (exponent
+ to_shift
));
660 frac
[fracsize
++] = cy
;
665 int width
= info
->width
;
666 char *buffer
, *startp
, *cp
;
669 int intdig_max
, intdig_no
= 0;
670 int fracdig_min
, fracdig_max
, fracdig_no
= 0;
674 if (tolower (info
->spec
) == 'e')
678 fracdig_min
= fracdig_max
= info
->prec
< 0 ? 6 : info
->prec
;
679 chars_needed
= 1 + 1 + fracdig_max
+ 1 + 1 + 4;
680 /* d . ddd e +- ddd */
681 dig_max
= INT_MAX
; /* Unlimited. */
682 significant
= 1; /* Does not matter here. */
684 else if (info
->spec
== 'f')
687 fracdig_min
= fracdig_max
= info
->prec
< 0 ? 6 : info
->prec
;
690 intdig_max
= exponent
+ 1;
691 /* This can be really big! */ /* XXX Maybe malloc if too big? */
692 chars_needed
= exponent
+ 1 + 1 + fracdig_max
;
697 chars_needed
= 1 + 1 + fracdig_max
;
699 dig_max
= INT_MAX
; /* Unlimited. */
700 significant
= 1; /* Does not matter here. */
704 dig_max
= info
->prec
< 0 ? 6 : (info
->prec
== 0 ? 1 : info
->prec
);
705 if ((expsign
== 0 && exponent
>= dig_max
)
706 || (expsign
!= 0 && exponent
> 4))
708 type
= isupper (info
->spec
) ? 'E' : 'e';
709 fracdig_max
= dig_max
- 1;
711 chars_needed
= 1 + 1 + fracdig_max
+ 1 + 1 + 4;
716 intdig_max
= expsign
== 0 ? exponent
+ 1 : 0;
717 fracdig_max
= dig_max
- intdig_max
;
718 /* We need space for the significant digits and perhaps for
719 leading zeros when < 1.0. Pessimistic guess: dig_max. */
720 chars_needed
= dig_max
+ dig_max
+ 1;
722 fracdig_min
= info
->alt
? fracdig_max
: 0;
723 significant
= 0; /* We count significant digits. */
727 /* Guess the number of groups we will make, and thus how
728 many spaces we need for separator characters. */
729 chars_needed
+= guess_grouping (intdig_max
, grouping
, thousands_sep
);
731 /* Allocate buffer for output. We need two more because while rounding
732 it is possible that we need two more characters in front of all the
734 buffer
= alloca (2 + chars_needed
);
735 cp
= startp
= buffer
+ 2; /* Let room for rounding. */
737 /* Do the real work: put digits in allocated buffer. */
738 if (expsign
== 0 || type
!= 'f')
740 assert (expsign
== 0 || intdig_max
== 1);
741 while (intdig_no
< intdig_max
)
744 *cp
++ = hack_digit ();
749 || (fracdig_max
> 0 && (fracsize
> 1 || frac
[0] != 0)))
754 /* |fp| < 1.0 and the selected type is 'f', so put "0."
761 /* Generate the needed number of fractional digits. */
762 while (fracdig_no
< fracdig_min
763 || (fracdig_no
< fracdig_max
&& (fracsize
> 1 || frac
[0] != 0)))
769 else if (significant
== 0)
779 digit
= hack_digit ();
785 /* This is the critical case. */
786 if (fracsize
== 1 && frac
[0] == 0)
787 /* Rest of the number is zero -> round to even.
788 (IEEE 754-1985 4.1 says this is the default rounding.) */
789 if ((*(cp
- 1) & 1) == 0)
794 /* Process fractional digits. Terminate if not rounded or
795 radix character is reached. */
796 while (*--tp
!= decimal
&& *tp
== '9')
803 if (fracdig_no
== 0 || *tp
== decimal
)
805 /* Round the integer digits. */
806 if (*(tp
- 1) == decimal
)
809 while (--tp
>= startp
&& *tp
== '9')
816 /* It is more citical. All digits were 9's. */
821 exponent
+= expsign
== 0 ? 1 : -1;
823 else if (intdig_no
== dig_max
)
825 /* This is the case where for type %g the number fits
826 really in the range for %f output but after rounding
827 the number of digits is too big. */
831 if (info
->alt
|| fracdig_no
> 0)
833 /* Overwrite the old radix character. */
834 startp
[intdig_no
+ 2] = '0';
838 fracdig_no
+= intdig_no
;
840 fracdig_max
= intdig_max
- intdig_no
;
842 /* Now we must print the exponent. */
843 type
= isupper (info
->spec
) ? 'E' : 'e';
847 /* We can simply add another another digit before the
853 /* While rounding the number of digits can change.
854 If the number now exceeds the limits remove some
855 fractional digits. */
856 if (intdig_no
+ fracdig_no
> dig_max
)
858 cp
-= intdig_no
+ fracdig_no
- dig_max
;
859 fracdig_no
-= intdig_no
+ fracdig_no
- dig_max
;
866 /* Now remove unnecessary '0' at the end of the string. */
867 while (fracdig_no
> fracdig_min
&& *(cp
- 1) == '0')
872 /* If we eliminate all fractional digits we perhaps also can remove
873 the radix character. */
874 if (fracdig_no
== 0 && !info
->alt
&& *(cp
- 1) == decimal
)
878 /* Add in separator characters, overwriting the same buffer. */
879 cp
= group_number (startp
, cp
, intdig_no
, grouping
, thousands_sep
);
881 /* Write the exponent if it is needed. */
885 *cp
++ = expsign
? '-' : '+';
887 /* Find the magnitude of the exponent. */
889 while (expscale
<= exponent
)
893 /* Exponent always has at least two digits. */
899 *cp
++ = '0' + (exponent
/ expscale
);
900 exponent
%= expscale
;
902 while (expscale
> 10);
903 *cp
++ = '0' + exponent
;
906 /* Compute number of characters which must be filled with the padding
908 if (is_neg
|| info
->showsign
|| info
->space
)
910 width
-= cp
- startp
;
912 if (!info
->left
&& info
->pad
!= '0' && width
> 0)
913 PADN (info
->pad
, width
);
917 else if (info
->showsign
)
919 else if (info
->space
)
922 if (!info
->left
&& info
->pad
== '0' && width
> 0)
925 PRINT (startp
, cp
- startp
);
927 if (info
->left
&& width
> 0)
928 PADN (info
->pad
, width
);
933 /* Return the number of extra grouping characters that will be inserted
934 into a number with INTDIG_MAX integer digits. */
937 guess_grouping (unsigned int intdig_max
, const char *grouping
, wchar_t sepchar
)
941 /* We treat all negative values like CHAR_MAX. */
943 if (*grouping
== CHAR_MAX
|| *grouping
<= 0)
944 /* No grouping should be done. */
948 while (intdig_max
> (unsigned int) *grouping
)
951 intdig_max
-= *grouping
++;
953 if (*grouping
== CHAR_MAX
|| *grouping
< 0)
954 /* No more grouping should be done. */
956 else if (*grouping
== 0)
958 /* Same grouping repeats. */
959 groups
+= intdig_max
/ grouping
[-1];
967 /* Group the INTDIG_NO integer digits of the number in [BUF,BUFEND).
968 There is guaranteed enough space past BUFEND to extend it.
969 Return the new end of buffer. */
972 group_number (char *buf
, char *bufend
, unsigned int intdig_no
,
973 const char *grouping
, wchar_t thousands_sep
)
975 unsigned int groups
= guess_grouping (intdig_no
, grouping
, thousands_sep
);
981 /* Move the fractional part down. */
982 memmove (buf
+ intdig_no
+ groups
, buf
+ intdig_no
,
983 bufend
- (buf
+ intdig_no
));
985 p
= buf
+ intdig_no
+ groups
- 1;
988 unsigned int len
= *grouping
++;
990 *p
-- = buf
[--intdig_no
];
992 *p
-- = thousands_sep
;
994 if (*grouping
== CHAR_MAX
|| *grouping
< 0)
995 /* No more grouping should be done. */
997 else if (*grouping
== 0)
998 /* Same grouping repeats. */
1000 } while (intdig_no
> (unsigned int) *grouping
);
1002 /* Copy the remaining ungrouped digits. */
1004 *p
-- = buf
[--intdig_no
];
1007 return bufend
+ groups
;