Remove _dl_initial_dtv
[glibc.git] / stdio-common / printf_fp.c
blob5f3c9042544b5a68f26bee7528c233b12fb115fe
1 /* Floating point output for `printf'.
2 Copyright (C) 1995-2012 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, see
19 <http://www.gnu.org/licenses/>. */
21 /* The gmp headers need some configuration frobs. */
22 #define HAVE_ALLOCA 1
24 #include <libioP.h>
25 #include <alloca.h>
26 #include <ctype.h>
27 #include <float.h>
28 #include <gmp-mparam.h>
29 #include <gmp.h>
30 #include <ieee754.h>
31 #include <stdlib/gmp-impl.h>
32 #include <stdlib/longlong.h>
33 #include <stdlib/fpioconst.h>
34 #include <locale/localeinfo.h>
35 #include <limits.h>
36 #include <math.h>
37 #include <printf.h>
38 #include <string.h>
39 #include <unistd.h>
40 #include <stdlib.h>
41 #include <wchar.h>
43 #ifdef COMPILE_WPRINTF
44 # define CHAR_T wchar_t
45 #else
46 # define CHAR_T char
47 #endif
49 #include "_i18n_number.h"
51 #ifndef NDEBUG
52 # define NDEBUG /* Undefine this for debugging assertions. */
53 #endif
54 #include <assert.h>
56 /* This defines make it possible to use the same code for GNU C library and
57 the GNU I/O library. */
58 #define PUT(f, s, n) _IO_sputn (f, s, n)
59 #define PAD(f, c, n) (wide ? _IO_wpadn (f, c, n) : _IO_padn (f, c, n))
60 /* We use this file GNU C library and GNU I/O library. So make
61 names equal. */
62 #undef putc
63 #define putc(c, f) (wide \
64 ? (int)_IO_putwc_unlocked (c, f) : _IO_putc_unlocked (c, f))
65 #define size_t _IO_size_t
66 #define FILE _IO_FILE
68 /* Macros for doing the actual output. */
70 #define outchar(ch) \
71 do \
72 { \
73 register const int outc = (ch); \
74 if (putc (outc, fp) == EOF) \
75 { \
76 if (buffer_malloced) \
77 free (wbuffer); \
78 return -1; \
79 } \
80 ++done; \
81 } while (0)
83 #define PRINT(ptr, wptr, len) \
84 do \
85 { \
86 register size_t outlen = (len); \
87 if (len > 20) \
88 { \
89 if (PUT (fp, wide ? (const char *) wptr : ptr, outlen) != outlen) \
90 { \
91 if (buffer_malloced) \
92 free (wbuffer); \
93 return -1; \
94 } \
95 ptr += outlen; \
96 done += outlen; \
97 } \
98 else \
99 { \
100 if (wide) \
101 while (outlen-- > 0) \
102 outchar (*wptr++); \
103 else \
104 while (outlen-- > 0) \
105 outchar (*ptr++); \
107 } while (0)
109 #define PADN(ch, len) \
110 do \
112 if (PAD (fp, ch, len) != len) \
114 if (buffer_malloced) \
115 free (wbuffer); \
116 return -1; \
118 done += len; \
120 while (0)
122 /* We use the GNU MP library to handle large numbers.
124 An MP variable occupies a varying number of entries in its array. We keep
125 track of this number for efficiency reasons. Otherwise we would always
126 have to process the whole array. */
127 #define MPN_VAR(name) mp_limb_t *name; mp_size_t name##size
129 #define MPN_ASSIGN(dst,src) \
130 memcpy (dst, src, (dst##size = src##size) * sizeof (mp_limb_t))
131 #define MPN_GE(u,v) \
132 (u##size > v##size || (u##size == v##size && __mpn_cmp (u, v, u##size) >= 0))
134 extern int __isinfl_internal (long double) attribute_hidden;
135 extern int __isnanl_internal (long double) attribute_hidden;
137 extern mp_size_t __mpn_extract_double (mp_ptr res_ptr, mp_size_t size,
138 int *expt, int *is_neg,
139 double value);
140 extern mp_size_t __mpn_extract_long_double (mp_ptr res_ptr, mp_size_t size,
141 int *expt, int *is_neg,
142 long double value);
143 extern unsigned int __guess_grouping (unsigned int intdig_max,
144 const char *grouping);
147 static wchar_t *group_number (wchar_t *buf, wchar_t *bufend,
148 unsigned int intdig_no, const char *grouping,
149 wchar_t thousands_sep, int ngroups)
150 internal_function;
154 ___printf_fp (FILE *fp,
155 const struct printf_info *info,
156 const void *const *args)
158 /* The floating-point value to output. */
159 union
161 double dbl;
162 __long_double_t ldbl;
164 fpnum;
166 /* Locale-dependent representation of decimal point. */
167 const char *decimal;
168 wchar_t decimalwc;
170 /* Locale-dependent thousands separator and grouping specification. */
171 const char *thousands_sep = NULL;
172 wchar_t thousands_sepwc = 0;
173 const char *grouping;
175 /* "NaN" or "Inf" for the special cases. */
176 const char *special = NULL;
177 const wchar_t *wspecial = NULL;
179 /* We need just a few limbs for the input before shifting to the right
180 position. */
181 mp_limb_t fp_input[(LDBL_MANT_DIG + BITS_PER_MP_LIMB - 1) / BITS_PER_MP_LIMB];
182 /* We need to shift the contents of fp_input by this amount of bits. */
183 int to_shift = 0;
185 /* The fraction of the floting-point value in question */
186 MPN_VAR(frac);
187 /* and the exponent. */
188 int exponent;
189 /* Sign of the exponent. */
190 int expsign = 0;
191 /* Sign of float number. */
192 int is_neg = 0;
194 /* Scaling factor. */
195 MPN_VAR(scale);
197 /* Temporary bignum value. */
198 MPN_VAR(tmp);
200 /* Digit which is result of last hack_digit() call. */
201 wchar_t digit;
203 /* The type of output format that will be used: 'e'/'E' or 'f'. */
204 int type;
206 /* Counter for number of written characters. */
207 int done = 0;
209 /* General helper (carry limb). */
210 mp_limb_t cy;
212 /* Nonzero if this is output on a wide character stream. */
213 int wide = info->wide;
215 /* Buffer in which we produce the output. */
216 wchar_t *wbuffer = NULL;
217 /* Flag whether wbuffer is malloc'ed or not. */
218 int buffer_malloced = 0;
220 auto wchar_t hack_digit (void);
222 wchar_t hack_digit (void)
224 mp_limb_t hi;
226 if (expsign != 0 && type == 'f' && exponent-- > 0)
227 hi = 0;
228 else if (scalesize == 0)
230 hi = frac[fracsize - 1];
231 frac[fracsize - 1] = __mpn_mul_1 (frac, frac, fracsize - 1, 10);
233 else
235 if (fracsize < scalesize)
236 hi = 0;
237 else
239 hi = mpn_divmod (tmp, frac, fracsize, scale, scalesize);
240 tmp[fracsize - scalesize] = hi;
241 hi = tmp[0];
243 fracsize = scalesize;
244 while (fracsize != 0 && frac[fracsize - 1] == 0)
245 --fracsize;
246 if (fracsize == 0)
248 /* We're not prepared for an mpn variable with zero
249 limbs. */
250 fracsize = 1;
251 return L'0' + hi;
255 mp_limb_t _cy = __mpn_mul_1 (frac, frac, fracsize, 10);
256 if (_cy != 0)
257 frac[fracsize++] = _cy;
260 return L'0' + hi;
264 /* Figure out the decimal point character. */
265 if (info->extra == 0)
267 decimal = _NL_CURRENT (LC_NUMERIC, DECIMAL_POINT);
268 decimalwc = _NL_CURRENT_WORD (LC_NUMERIC, _NL_NUMERIC_DECIMAL_POINT_WC);
270 else
272 decimal = _NL_CURRENT (LC_MONETARY, MON_DECIMAL_POINT);
273 if (*decimal == '\0')
274 decimal = _NL_CURRENT (LC_NUMERIC, DECIMAL_POINT);
275 decimalwc = _NL_CURRENT_WORD (LC_MONETARY,
276 _NL_MONETARY_DECIMAL_POINT_WC);
277 if (decimalwc == L'\0')
278 decimalwc = _NL_CURRENT_WORD (LC_NUMERIC,
279 _NL_NUMERIC_DECIMAL_POINT_WC);
281 /* The decimal point character must not be zero. */
282 assert (*decimal != '\0');
283 assert (decimalwc != L'\0');
285 if (info->group)
287 if (info->extra == 0)
288 grouping = _NL_CURRENT (LC_NUMERIC, GROUPING);
289 else
290 grouping = _NL_CURRENT (LC_MONETARY, MON_GROUPING);
292 if (*grouping <= 0 || *grouping == CHAR_MAX)
293 grouping = NULL;
294 else
296 /* Figure out the thousands separator character. */
297 if (wide)
299 if (info->extra == 0)
300 thousands_sepwc =
301 _NL_CURRENT_WORD (LC_NUMERIC, _NL_NUMERIC_THOUSANDS_SEP_WC);
302 else
303 thousands_sepwc =
304 _NL_CURRENT_WORD (LC_MONETARY,
305 _NL_MONETARY_THOUSANDS_SEP_WC);
307 else
309 if (info->extra == 0)
310 thousands_sep = _NL_CURRENT (LC_NUMERIC, THOUSANDS_SEP);
311 else
312 thousands_sep = _NL_CURRENT (LC_MONETARY, MON_THOUSANDS_SEP);
315 if ((wide && thousands_sepwc == L'\0')
316 || (! wide && *thousands_sep == '\0'))
317 grouping = NULL;
318 else if (thousands_sepwc == L'\0')
319 /* If we are printing multibyte characters and there is a
320 multibyte representation for the thousands separator,
321 we must ensure the wide character thousands separator
322 is available, even if it is fake. */
323 thousands_sepwc = 0xfffffffe;
326 else
327 grouping = NULL;
329 /* Fetch the argument value. */
330 #ifndef __NO_LONG_DOUBLE_MATH
331 if (info->is_long_double && sizeof (long double) > sizeof (double))
333 fpnum.ldbl = *(const long double *) args[0];
335 /* Check for special values: not a number or infinity. */
336 int res;
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))
343 special = "NAN";
344 wspecial = L"NAN";
346 else
348 special = "nan";
349 wspecial = L"nan";
352 else if ((res = __isinfl (fpnum.ldbl)))
354 is_neg = res < 0;
355 if (isupper (info->spec))
357 special = "INF";
358 wspecial = L"INF";
360 else
362 special = "inf";
363 wspecial = L"inf";
366 else
368 fracsize = __mpn_extract_long_double (fp_input,
369 (sizeof (fp_input) /
370 sizeof (fp_input[0])),
371 &exponent, &is_neg,
372 fpnum.ldbl);
373 to_shift = 1 + fracsize * BITS_PER_MP_LIMB - LDBL_MANT_DIG;
376 else
377 #endif /* no long double */
379 fpnum.dbl = *(const double *) args[0];
381 /* Check for special values: not a number or infinity. */
382 int res;
383 if (__isnan (fpnum.dbl))
385 union ieee754_double u = { .d = fpnum.dbl };
386 is_neg = u.ieee.negative != 0;
387 if (isupper (info->spec))
389 special = "NAN";
390 wspecial = L"NAN";
392 else
394 special = "nan";
395 wspecial = L"nan";
398 else if ((res = __isinf (fpnum.dbl)))
400 is_neg = res < 0;
401 if (isupper (info->spec))
403 special = "INF";
404 wspecial = L"INF";
406 else
408 special = "inf";
409 wspecial = L"inf";
412 else
414 fracsize = __mpn_extract_double (fp_input,
415 (sizeof (fp_input)
416 / sizeof (fp_input[0])),
417 &exponent, &is_neg, fpnum.dbl);
418 to_shift = 1 + fracsize * BITS_PER_MP_LIMB - DBL_MANT_DIG;
422 if (special)
424 int width = info->width;
426 if (is_neg || info->showsign || info->space)
427 --width;
428 width -= 3;
430 if (!info->left && width > 0)
431 PADN (' ', width);
433 if (is_neg)
434 outchar ('-');
435 else if (info->showsign)
436 outchar ('+');
437 else if (info->space)
438 outchar (' ');
440 PRINT (special, wspecial, 3);
442 if (info->left && width > 0)
443 PADN (' ', width);
445 return done;
449 /* We need three multiprecision variables. Now that we have the exponent
450 of the number we can allocate the needed memory. It would be more
451 efficient to use variables of the fixed maximum size but because this
452 would be really big it could lead to memory problems. */
454 mp_size_t bignum_size = ((ABS (exponent) + BITS_PER_MP_LIMB - 1)
455 / BITS_PER_MP_LIMB
456 + (LDBL_MANT_DIG / BITS_PER_MP_LIMB > 2 ? 8 : 4))
457 * sizeof (mp_limb_t);
458 frac = (mp_limb_t *) alloca (bignum_size);
459 tmp = (mp_limb_t *) alloca (bignum_size);
460 scale = (mp_limb_t *) alloca (bignum_size);
463 /* We now have to distinguish between numbers with positive and negative
464 exponents because the method used for the one is not applicable/efficient
465 for the other. */
466 scalesize = 0;
467 if (exponent > 2)
469 /* |FP| >= 8.0. */
470 int scaleexpo = 0;
471 int explog = LDBL_MAX_10_EXP_LOG;
472 int exp10 = 0;
473 const struct mp_power *powers = &_fpioconst_pow10[explog + 1];
474 int cnt_h, cnt_l, i;
476 if ((exponent + to_shift) % BITS_PER_MP_LIMB == 0)
478 MPN_COPY_DECR (frac + (exponent + to_shift) / BITS_PER_MP_LIMB,
479 fp_input, fracsize);
480 fracsize += (exponent + to_shift) / BITS_PER_MP_LIMB;
482 else
484 cy = __mpn_lshift (frac + (exponent + to_shift) / BITS_PER_MP_LIMB,
485 fp_input, fracsize,
486 (exponent + to_shift) % BITS_PER_MP_LIMB);
487 fracsize += (exponent + to_shift) / BITS_PER_MP_LIMB;
488 if (cy)
489 frac[fracsize++] = cy;
491 MPN_ZERO (frac, (exponent + to_shift) / BITS_PER_MP_LIMB);
493 assert (powers > &_fpioconst_pow10[0]);
496 --powers;
498 /* The number of the product of two binary numbers with n and m
499 bits respectively has m+n or m+n-1 bits. */
500 if (exponent >= scaleexpo + powers->p_expo - 1)
502 if (scalesize == 0)
504 #ifndef __NO_LONG_DOUBLE_MATH
505 if (LDBL_MANT_DIG > _FPIO_CONST_OFFSET * BITS_PER_MP_LIMB
506 && info->is_long_double)
508 #define _FPIO_CONST_SHIFT \
509 (((LDBL_MANT_DIG + BITS_PER_MP_LIMB - 1) / BITS_PER_MP_LIMB) \
510 - _FPIO_CONST_OFFSET)
511 /* 64bit const offset is not enough for
512 IEEE quad long double. */
513 tmpsize = powers->arraysize + _FPIO_CONST_SHIFT;
514 memcpy (tmp + _FPIO_CONST_SHIFT,
515 &__tens[powers->arrayoff],
516 tmpsize * sizeof (mp_limb_t));
517 MPN_ZERO (tmp, _FPIO_CONST_SHIFT);
518 /* Adjust exponent, as scaleexpo will be this much
519 bigger too. */
520 exponent += _FPIO_CONST_SHIFT * BITS_PER_MP_LIMB;
522 else
523 #endif
525 tmpsize = powers->arraysize;
526 memcpy (tmp, &__tens[powers->arrayoff],
527 tmpsize * sizeof (mp_limb_t));
530 else
532 cy = __mpn_mul (tmp, scale, scalesize,
533 &__tens[powers->arrayoff
534 + _FPIO_CONST_OFFSET],
535 powers->arraysize - _FPIO_CONST_OFFSET);
536 tmpsize = scalesize + powers->arraysize - _FPIO_CONST_OFFSET;
537 if (cy == 0)
538 --tmpsize;
541 if (MPN_GE (frac, tmp))
543 int cnt;
544 MPN_ASSIGN (scale, tmp);
545 count_leading_zeros (cnt, scale[scalesize - 1]);
546 scaleexpo = (scalesize - 2) * BITS_PER_MP_LIMB - cnt - 1;
547 exp10 |= 1 << explog;
550 --explog;
552 while (powers > &_fpioconst_pow10[0]);
553 exponent = exp10;
555 /* Optimize number representations. We want to represent the numbers
556 with the lowest number of bytes possible without losing any
557 bytes. Also the highest bit in the scaling factor has to be set
558 (this is a requirement of the MPN division routines). */
559 if (scalesize > 0)
561 /* Determine minimum number of zero bits at the end of
562 both numbers. */
563 for (i = 0; scale[i] == 0 && frac[i] == 0; i++)
566 /* Determine number of bits the scaling factor is misplaced. */
567 count_leading_zeros (cnt_h, scale[scalesize - 1]);
569 if (cnt_h == 0)
571 /* The highest bit of the scaling factor is already set. So
572 we only have to remove the trailing empty limbs. */
573 if (i > 0)
575 MPN_COPY_INCR (scale, scale + i, scalesize - i);
576 scalesize -= i;
577 MPN_COPY_INCR (frac, frac + i, fracsize - i);
578 fracsize -= i;
581 else
583 if (scale[i] != 0)
585 count_trailing_zeros (cnt_l, scale[i]);
586 if (frac[i] != 0)
588 int cnt_l2;
589 count_trailing_zeros (cnt_l2, frac[i]);
590 if (cnt_l2 < cnt_l)
591 cnt_l = cnt_l2;
594 else
595 count_trailing_zeros (cnt_l, frac[i]);
597 /* Now shift the numbers to their optimal position. */
598 if (i == 0 && BITS_PER_MP_LIMB - cnt_h > cnt_l)
600 /* We cannot save any memory. So just roll both numbers
601 so that the scaling factor has its highest bit set. */
603 (void) __mpn_lshift (scale, scale, scalesize, cnt_h);
604 cy = __mpn_lshift (frac, frac, fracsize, cnt_h);
605 if (cy != 0)
606 frac[fracsize++] = cy;
608 else if (BITS_PER_MP_LIMB - cnt_h <= cnt_l)
610 /* We can save memory by removing the trailing zero limbs
611 and by packing the non-zero limbs which gain another
612 free one. */
614 (void) __mpn_rshift (scale, scale + i, scalesize - i,
615 BITS_PER_MP_LIMB - cnt_h);
616 scalesize -= i + 1;
617 (void) __mpn_rshift (frac, frac + i, fracsize - i,
618 BITS_PER_MP_LIMB - cnt_h);
619 fracsize -= frac[fracsize - i - 1] == 0 ? i + 1 : i;
621 else
623 /* We can only save the memory of the limbs which are zero.
624 The non-zero parts occupy the same number of limbs. */
626 (void) __mpn_rshift (scale, scale + (i - 1),
627 scalesize - (i - 1),
628 BITS_PER_MP_LIMB - cnt_h);
629 scalesize -= i;
630 (void) __mpn_rshift (frac, frac + (i - 1),
631 fracsize - (i - 1),
632 BITS_PER_MP_LIMB - cnt_h);
633 fracsize -= frac[fracsize - (i - 1) - 1] == 0 ? i : i - 1;
638 else if (exponent < 0)
640 /* |FP| < 1.0. */
641 int exp10 = 0;
642 int explog = LDBL_MAX_10_EXP_LOG;
643 const struct mp_power *powers = &_fpioconst_pow10[explog + 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));
650 expsign = 1;
651 exponent = -exponent;
653 assert (powers != &_fpioconst_pow10[0]);
656 --powers;
658 if (exponent >= powers->m_expo)
660 int i, incr, cnt_h, cnt_l;
661 mp_limb_t topval[2];
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,
669 frac, fracsize);
670 else
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;
675 if (cy == 0)
676 --tmpsize;
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)
691 topval[0] = 0;
692 topval[1]
693 = ((mp_limb_t) 10) << (BITS_PER_MP_LIMB - 4 - cnt_h);
695 else
697 topval[0] = ((mp_limb_t) 10) << (BITS_PER_MP_LIMB - 4);
698 topval[1] = 0;
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
716 exponents. */
717 exponent -= incr;
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. */
722 if (exponent < 0)
723 cnt_h += -exponent;
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;
732 else
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
741 separate limb. */
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;
753 else
755 /* We can only save the memory of the limbs which
756 are zero. The non-zero parts occupy the same
757 number of limbs. */
759 (void) __mpn_rshift (frac, tmp + (i - 1),
760 tmpsize - (i - 1),
761 BITS_PER_MP_LIMB - 1 - cnt_h);
762 fracsize = tmpsize - (i - 1);
767 --explog;
769 while (powers != &_fpioconst_pow10[1] && exponent > 0);
770 /* All factors but 10^-1 are tested now. */
771 if (exponent > 0)
773 int cnt_l;
775 cy = __mpn_mul_1 (tmp, frac, fracsize, 10);
776 tmpsize = fracsize;
777 assert (cy == 0 || tmp[tmpsize - 1] < 20);
779 count_trailing_zeros (cnt_l, tmp[0]);
780 if (cnt_l < MIN (4, exponent))
782 cy = __mpn_lshift (frac, tmp, tmpsize,
783 BITS_PER_MP_LIMB - MIN (4, exponent));
784 if (cy != 0)
785 frac[tmpsize++] = cy;
787 else
788 (void) __mpn_rshift (frac, tmp, tmpsize, MIN (4, exponent));
789 fracsize = tmpsize;
790 exp10 |= 1;
791 assert (frac[fracsize - 1] < 10);
793 exponent = exp10;
795 else
797 /* This is a special case. We don't need a factor because the
798 numbers are in the range of 1.0 <= |fp| < 8.0. We simply
799 shift it to the right place and divide it by 1.0 to get the
800 leading digit. (Of course this division is not really made.) */
801 assert (0 <= exponent && exponent < 3 &&
802 exponent + to_shift < BITS_PER_MP_LIMB);
804 /* Now shift the input value to its right place. */
805 cy = __mpn_lshift (frac, fp_input, fracsize, (exponent + to_shift));
806 frac[fracsize++] = cy;
807 exponent = 0;
811 int width = info->width;
812 wchar_t *wstartp, *wcp;
813 size_t chars_needed;
814 int expscale;
815 int intdig_max, intdig_no = 0;
816 int fracdig_min;
817 int fracdig_max;
818 int dig_max;
819 int significant;
820 int ngroups = 0;
821 char spec = _tolower (info->spec);
823 if (spec == 'e')
825 type = info->spec;
826 intdig_max = 1;
827 fracdig_min = fracdig_max = info->prec < 0 ? 6 : info->prec;
828 chars_needed = 1 + 1 + (size_t) fracdig_max + 1 + 1 + 4;
829 /* d . ddd e +- ddd */
830 dig_max = INT_MAX; /* Unlimited. */
831 significant = 1; /* Does not matter here. */
833 else if (spec == 'f')
835 type = 'f';
836 fracdig_min = fracdig_max = info->prec < 0 ? 6 : info->prec;
837 dig_max = INT_MAX; /* Unlimited. */
838 significant = 1; /* Does not matter here. */
839 if (expsign == 0)
841 intdig_max = exponent + 1;
842 /* This can be really big! */ /* XXX Maybe malloc if too big? */
843 chars_needed = (size_t) exponent + 1 + 1 + (size_t) fracdig_max;
845 else
847 intdig_max = 1;
848 chars_needed = 1 + 1 + (size_t) fracdig_max;
851 else
853 dig_max = info->prec < 0 ? 6 : (info->prec == 0 ? 1 : info->prec);
854 if ((expsign == 0 && exponent >= dig_max)
855 || (expsign != 0 && exponent > 4))
857 if ('g' - 'G' == 'e' - 'E')
858 type = 'E' + (info->spec - 'G');
859 else
860 type = isupper (info->spec) ? 'E' : 'e';
861 fracdig_max = dig_max - 1;
862 intdig_max = 1;
863 chars_needed = 1 + 1 + (size_t) fracdig_max + 1 + 1 + 4;
865 else
867 type = 'f';
868 intdig_max = expsign == 0 ? exponent + 1 : 0;
869 fracdig_max = dig_max - intdig_max;
870 /* We need space for the significant digits and perhaps
871 for leading zeros when < 1.0. The number of leading
872 zeros can be as many as would be required for
873 exponential notation with a negative two-digit
874 exponent, which is 4. */
875 chars_needed = (size_t) dig_max + 1 + 4;
877 fracdig_min = info->alt ? fracdig_max : 0;
878 significant = 0; /* We count significant digits. */
881 if (grouping)
883 /* Guess the number of groups we will make, and thus how
884 many spaces we need for separator characters. */
885 ngroups = __guess_grouping (intdig_max, grouping);
886 /* Allocate one more character in case rounding increases the
887 number of groups. */
888 chars_needed += ngroups + 1;
891 /* Allocate buffer for output. We need two more because while rounding
892 it is possible that we need two more characters in front of all the
893 other output. If the amount of memory we have to allocate is too
894 large use `malloc' instead of `alloca'. */
895 if (__builtin_expect (chars_needed >= (size_t) -1 / sizeof (wchar_t) - 2
896 || chars_needed < fracdig_max, 0))
898 /* Some overflow occurred. */
899 __set_errno (ERANGE);
900 return -1;
902 size_t wbuffer_to_alloc = (2 + chars_needed) * sizeof (wchar_t);
903 buffer_malloced = ! __libc_use_alloca (wbuffer_to_alloc);
904 if (__builtin_expect (buffer_malloced, 0))
906 wbuffer = (wchar_t *) malloc (wbuffer_to_alloc);
907 if (wbuffer == NULL)
908 /* Signal an error to the caller. */
909 return -1;
911 else
912 wbuffer = (wchar_t *) alloca (wbuffer_to_alloc);
913 wcp = wstartp = wbuffer + 2; /* Let room for rounding. */
915 /* Do the real work: put digits in allocated buffer. */
916 if (expsign == 0 || type != 'f')
918 assert (expsign == 0 || intdig_max == 1);
919 while (intdig_no < intdig_max)
921 ++intdig_no;
922 *wcp++ = hack_digit ();
924 significant = 1;
925 if (info->alt
926 || fracdig_min > 0
927 || (fracdig_max > 0 && (fracsize > 1 || frac[0] != 0)))
928 *wcp++ = decimalwc;
930 else
932 /* |fp| < 1.0 and the selected type is 'f', so put "0."
933 in the buffer. */
934 *wcp++ = L'0';
935 --exponent;
936 *wcp++ = decimalwc;
939 /* Generate the needed number of fractional digits. */
940 int fracdig_no = 0;
941 int added_zeros = 0;
942 while (fracdig_no < fracdig_min + added_zeros
943 || (fracdig_no < fracdig_max && (fracsize > 1 || frac[0] != 0)))
945 ++fracdig_no;
946 *wcp = hack_digit ();
947 if (*wcp++ != L'0')
948 significant = 1;
949 else if (significant == 0)
951 ++fracdig_max;
952 if (fracdig_min > 0)
953 ++added_zeros;
957 /* Do rounding. */
958 digit = hack_digit ();
959 if (digit > L'4')
961 wchar_t *wtp = wcp;
963 if (digit == L'5'
964 && ((*(wcp - 1) != decimalwc && (*(wcp - 1) & 1) == 0)
965 || ((*(wcp - 1) == decimalwc && (*(wcp - 2) & 1) == 0))))
967 /* This is the critical case. */
968 if (fracsize == 1 && frac[0] == 0)
969 /* Rest of the number is zero -> round to even.
970 (IEEE 754-1985 4.1 says this is the default rounding.) */
971 goto do_expo;
972 else if (scalesize == 0)
974 /* Here we have to see whether all limbs are zero since no
975 normalization happened. */
976 size_t lcnt = fracsize;
977 while (lcnt >= 1 && frac[lcnt - 1] == 0)
978 --lcnt;
979 if (lcnt == 0)
980 /* Rest of the number is zero -> round to even.
981 (IEEE 754-1985 4.1 says this is the default rounding.) */
982 goto do_expo;
986 if (fracdig_no > 0)
988 /* Process fractional digits. Terminate if not rounded or
989 radix character is reached. */
990 int removed = 0;
991 while (*--wtp != decimalwc && *wtp == L'9')
993 *wtp = L'0';
994 ++removed;
996 if (removed == fracdig_min && added_zeros > 0)
997 --added_zeros;
998 if (*wtp != decimalwc)
999 /* Round up. */
1000 (*wtp)++;
1001 else if (__builtin_expect (spec == 'g' && type == 'f' && info->alt
1002 && wtp == wstartp + 1
1003 && wstartp[0] == L'0',
1005 /* This is a special case: the rounded number is 1.0,
1006 the format is 'g' or 'G', and the alternative format
1007 is selected. This means the result must be "1.". */
1008 --added_zeros;
1011 if (fracdig_no == 0 || *wtp == decimalwc)
1013 /* Round the integer digits. */
1014 if (*(wtp - 1) == decimalwc)
1015 --wtp;
1017 while (--wtp >= wstartp && *wtp == L'9')
1018 *wtp = L'0';
1020 if (wtp >= wstartp)
1021 /* Round up. */
1022 (*wtp)++;
1023 else
1024 /* It is more critical. All digits were 9's. */
1026 if (type != 'f')
1028 *wstartp = '1';
1029 exponent += expsign == 0 ? 1 : -1;
1031 /* The above exponent adjustment could lead to 1.0e-00,
1032 e.g. for 0.999999999. Make sure exponent 0 always
1033 uses + sign. */
1034 if (exponent == 0)
1035 expsign = 0;
1037 else if (intdig_no == dig_max)
1039 /* This is the case where for type %g the number fits
1040 really in the range for %f output but after rounding
1041 the number of digits is too big. */
1042 *--wstartp = decimalwc;
1043 *--wstartp = L'1';
1045 if (info->alt || fracdig_no > 0)
1047 /* Overwrite the old radix character. */
1048 wstartp[intdig_no + 2] = L'0';
1049 ++fracdig_no;
1052 fracdig_no += intdig_no;
1053 intdig_no = 1;
1054 fracdig_max = intdig_max - intdig_no;
1055 ++exponent;
1056 /* Now we must print the exponent. */
1057 type = isupper (info->spec) ? 'E' : 'e';
1059 else
1061 /* We can simply add another another digit before the
1062 radix. */
1063 *--wstartp = L'1';
1064 ++intdig_no;
1067 /* While rounding the number of digits can change.
1068 If the number now exceeds the limits remove some
1069 fractional digits. */
1070 if (intdig_no + fracdig_no > dig_max)
1072 wcp -= intdig_no + fracdig_no - dig_max;
1073 fracdig_no -= intdig_no + fracdig_no - dig_max;
1079 do_expo:
1080 /* Now remove unnecessary '0' at the end of the string. */
1081 while (fracdig_no > fracdig_min + added_zeros && *(wcp - 1) == L'0')
1083 --wcp;
1084 --fracdig_no;
1086 /* If we eliminate all fractional digits we perhaps also can remove
1087 the radix character. */
1088 if (fracdig_no == 0 && !info->alt && *(wcp - 1) == decimalwc)
1089 --wcp;
1091 if (grouping)
1093 /* Rounding might have changed the number of groups. We allocated
1094 enough memory but we need here the correct number of groups. */
1095 if (intdig_no != intdig_max)
1096 ngroups = __guess_grouping (intdig_no, grouping);
1098 /* Add in separator characters, overwriting the same buffer. */
1099 wcp = group_number (wstartp, wcp, intdig_no, grouping, thousands_sepwc,
1100 ngroups);
1103 /* Write the exponent if it is needed. */
1104 if (type != 'f')
1106 if (__builtin_expect (expsign != 0 && exponent == 4 && spec == 'g', 0))
1108 /* This is another special case. The exponent of the number is
1109 really smaller than -4, which requires the 'e'/'E' format.
1110 But after rounding the number has an exponent of -4. */
1111 assert (wcp >= wstartp + 1);
1112 assert (wstartp[0] == L'1');
1113 __wmemcpy (wstartp, L"0.0001", 6);
1114 wstartp[1] = decimalwc;
1115 if (wcp >= wstartp + 2)
1117 wmemset (wstartp + 6, L'0', wcp - (wstartp + 2));
1118 wcp += 4;
1120 else
1121 wcp += 5;
1123 else
1125 *wcp++ = (wchar_t) type;
1126 *wcp++ = expsign ? L'-' : L'+';
1128 /* Find the magnitude of the exponent. */
1129 expscale = 10;
1130 while (expscale <= exponent)
1131 expscale *= 10;
1133 if (exponent < 10)
1134 /* Exponent always has at least two digits. */
1135 *wcp++ = L'0';
1136 else
1139 expscale /= 10;
1140 *wcp++ = L'0' + (exponent / expscale);
1141 exponent %= expscale;
1143 while (expscale > 10);
1144 *wcp++ = L'0' + exponent;
1148 /* Compute number of characters which must be filled with the padding
1149 character. */
1150 if (is_neg || info->showsign || info->space)
1151 --width;
1152 width -= wcp - wstartp;
1154 if (!info->left && info->pad != '0' && width > 0)
1155 PADN (info->pad, width);
1157 if (is_neg)
1158 outchar ('-');
1159 else if (info->showsign)
1160 outchar ('+');
1161 else if (info->space)
1162 outchar (' ');
1164 if (!info->left && info->pad == '0' && width > 0)
1165 PADN ('0', width);
1168 char *buffer = NULL;
1169 char *buffer_end = NULL;
1170 char *cp = NULL;
1171 char *tmpptr;
1173 if (! wide)
1175 /* Create the single byte string. */
1176 size_t decimal_len;
1177 size_t thousands_sep_len;
1178 wchar_t *copywc;
1179 size_t factor = (info->i18n
1180 ? _NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_MB_CUR_MAX)
1181 : 1);
1183 decimal_len = strlen (decimal);
1185 if (thousands_sep == NULL)
1186 thousands_sep_len = 0;
1187 else
1188 thousands_sep_len = strlen (thousands_sep);
1190 size_t nbuffer = (2 + chars_needed * factor + decimal_len
1191 + ngroups * thousands_sep_len);
1192 if (__builtin_expect (buffer_malloced, 0))
1194 buffer = (char *) malloc (nbuffer);
1195 if (buffer == NULL)
1197 /* Signal an error to the caller. */
1198 free (wbuffer);
1199 return -1;
1202 else
1203 buffer = (char *) alloca (nbuffer);
1204 buffer_end = buffer + nbuffer;
1206 /* Now copy the wide character string. Since the character
1207 (except for the decimal point and thousands separator) must
1208 be coming from the ASCII range we can esily convert the
1209 string without mapping tables. */
1210 for (cp = buffer, copywc = wstartp; copywc < wcp; ++copywc)
1211 if (*copywc == decimalwc)
1212 cp = (char *) __mempcpy (cp, decimal, decimal_len);
1213 else if (*copywc == thousands_sepwc)
1214 cp = (char *) __mempcpy (cp, thousands_sep, thousands_sep_len);
1215 else
1216 *cp++ = (char) *copywc;
1219 tmpptr = buffer;
1220 if (__builtin_expect (info->i18n, 0))
1222 #ifdef COMPILE_WPRINTF
1223 wstartp = _i18n_number_rewrite (wstartp, wcp,
1224 wbuffer + wbuffer_to_alloc);
1225 wcp = wbuffer + wbuffer_to_alloc;
1226 assert ((uintptr_t) wbuffer <= (uintptr_t) wstartp);
1227 assert ((uintptr_t) wstartp
1228 < (uintptr_t) wbuffer + wbuffer_to_alloc);
1229 #else
1230 tmpptr = _i18n_number_rewrite (tmpptr, cp, buffer_end);
1231 cp = buffer_end;
1232 assert ((uintptr_t) buffer <= (uintptr_t) tmpptr);
1233 assert ((uintptr_t) tmpptr < (uintptr_t) buffer_end);
1234 #endif
1237 PRINT (tmpptr, wstartp, wide ? wcp - wstartp : cp - tmpptr);
1239 /* Free the memory if necessary. */
1240 if (__builtin_expect (buffer_malloced, 0))
1242 free (buffer);
1243 free (wbuffer);
1247 if (info->left && width > 0)
1248 PADN (info->pad, width);
1250 return done;
1252 ldbl_hidden_def (___printf_fp, __printf_fp)
1253 ldbl_strong_alias (___printf_fp, __printf_fp)
1255 /* Return the number of extra grouping characters that will be inserted
1256 into a number with INTDIG_MAX integer digits. */
1258 unsigned int
1259 __guess_grouping (unsigned int intdig_max, const char *grouping)
1261 unsigned int groups;
1263 /* We treat all negative values like CHAR_MAX. */
1265 if (*grouping == CHAR_MAX || *grouping <= 0)
1266 /* No grouping should be done. */
1267 return 0;
1269 groups = 0;
1270 while (intdig_max > (unsigned int) *grouping)
1272 ++groups;
1273 intdig_max -= *grouping++;
1275 if (*grouping == CHAR_MAX
1276 #if CHAR_MIN < 0
1277 || *grouping < 0
1278 #endif
1280 /* No more grouping should be done. */
1281 break;
1282 else if (*grouping == 0)
1284 /* Same grouping repeats. */
1285 groups += (intdig_max - 1) / grouping[-1];
1286 break;
1290 return groups;
1293 /* Group the INTDIG_NO integer digits of the number in [BUF,BUFEND).
1294 There is guaranteed enough space past BUFEND to extend it.
1295 Return the new end of buffer. */
1297 static wchar_t *
1298 internal_function
1299 group_number (wchar_t *buf, wchar_t *bufend, unsigned int intdig_no,
1300 const char *grouping, wchar_t thousands_sep, int ngroups)
1302 wchar_t *p;
1304 if (ngroups == 0)
1305 return bufend;
1307 /* Move the fractional part down. */
1308 __wmemmove (buf + intdig_no + ngroups, buf + intdig_no,
1309 bufend - (buf + intdig_no));
1311 p = buf + intdig_no + ngroups - 1;
1314 unsigned int len = *grouping++;
1316 *p-- = buf[--intdig_no];
1317 while (--len > 0);
1318 *p-- = thousands_sep;
1320 if (*grouping == CHAR_MAX
1321 #if CHAR_MIN < 0
1322 || *grouping < 0
1323 #endif
1325 /* No more grouping should be done. */
1326 break;
1327 else if (*grouping == 0)
1328 /* Same grouping repeats. */
1329 --grouping;
1330 } while (intdig_no > (unsigned int) *grouping);
1332 /* Copy the remaining ungrouped digits. */
1334 *p-- = buf[--intdig_no];
1335 while (p > buf);
1337 return bufend + ngroups;