1/* Print floating point number in hexadecimal notation according to ISO C99.
2   Copyright (C) 1997-2012 Free Software Foundation, Inc.
3   This file is part of the GNU C Library.
4   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
5
6   The GNU C Library is free software; you can redistribute it and/or
7   modify it under the terms of the GNU Lesser General Public
8   License as published by the Free Software Foundation; either
9   version 2.1 of the License, or (at your option) any later version.
10
11   The GNU C Library is distributed in the hope that it will be useful,
12   but WITHOUT ANY WARRANTY; without even the implied warranty of
13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14   Lesser General Public License for more details.
15
16   You should have received a copy of the GNU Lesser General Public
17   License along with the GNU C Library; if not, see
18   <http://www.gnu.org/licenses/>.  */
19
20#include <config.h>
21#include <math.h>
22#include <stdlib.h>
23#include <stdio.h>
24#include <string.h>
25#include <stdbool.h>
26#define NDEBUG
27#include <assert.h>
28#include "quadmath-rounding-mode.h"
29#include "quadmath-printf.h"
30#include "_itoa.h"
31#include "_itowa.h"
32
33
34/* Macros for doing the actual output.  */
35
36#define outchar(ch)							      \
37  do									      \
38    {									      \
39      register const int outc = (ch);					      \
40      if (PUTC (outc, fp) == EOF)					      \
41	return -1;							      \
42      ++done;								      \
43    } while (0)
44
45#define PRINT(ptr, wptr, len)						      \
46  do									      \
47    {									      \
48      register size_t outlen = (len);					      \
49      if (wide)								      \
50	while (outlen-- > 0)						      \
51	  outchar (*wptr++);						      \
52      else								      \
53	while (outlen-- > 0)						      \
54	  outchar (*ptr++);						      \
55    } while (0)
56
57#define PADN(ch, len)							      \
58  do									      \
59    {									      \
60      if (PAD (fp, ch, len) != len)					      \
61	return -1;							      \
62      done += len;							      \
63    }									      \
64  while (0)
65
66
67
68int
69__quadmath_printf_fphex (struct __quadmath_printf_file *fp,
70			 const struct printf_info *info,
71			 const void *const *args)
72{
73  /* The floating-point value to output.  */
74  ieee854_float128 fpnum;
75
76  /* Locale-dependent representation of decimal point.	*/
77  const char *decimal;
78  wchar_t decimalwc;
79
80  /* "NaN" or "Inf" for the special cases.  */
81  const char *special = NULL;
82  const wchar_t *wspecial = NULL;
83
84  /* Buffer for the generated number string for the mantissa.  The
85     maximal size for the mantissa is 128 bits.  */
86  char numbuf[32];
87  char *numstr;
88  char *numend;
89  wchar_t wnumbuf[32];
90  wchar_t *wnumstr;
91  wchar_t *wnumend;
92  int negative;
93
94  /* The maximal exponent of two in decimal notation has 5 digits.  */
95  char expbuf[5];
96  char *expstr;
97  wchar_t wexpbuf[5];
98  wchar_t *wexpstr;
99  int expnegative;
100  int exponent;
101
102  /* Non-zero is mantissa is zero.  */
103  int zero_mantissa;
104
105  /* The leading digit before the decimal point.  */
106  char leading;
107
108  /* Precision.  */
109  int precision = info->prec;
110
111  /* Width.  */
112  int width = info->width;
113
114  /* Number of characters written.  */
115  int done = 0;
116
117  /* Nonzero if this is output on a wide character stream.  */
118  int wide = info->wide;
119
120  bool do_round_away;
121
122  /* Figure out the decimal point character.  */
123#ifdef USE_NL_LANGINFO
124  if (info->extra == 0)
125    decimal = nl_langinfo (DECIMAL_POINT);
126  else
127    {
128      decimal = nl_langinfo (MON_DECIMAL_POINT);
129      if (*decimal == '\0')
130	decimal = nl_langinfo (DECIMAL_POINT);
131    }
132  /* The decimal point character must never be zero.  */
133  assert (*decimal != '\0');
134#elif defined USE_LOCALECONV
135  const struct lconv *lc = localeconv ();
136  if (info->extra == 0)
137    decimal = lc->decimal_point;
138  else
139    {
140      decimal = lc->mon_decimal_point;
141      if (decimal == NULL || *decimal == '\0')
142	decimal = lc->decimal_point;
143    }
144  if (decimal == NULL || *decimal == '\0')
145    decimal = ".";
146#else
147  decimal = ".";
148#endif
149#ifdef USE_NL_LANGINFO_WC
150  if (info->extra == 0)
151    decimalwc = nl_langinfo_wc (_NL_NUMERIC_DECIMAL_POINT_WC);
152  else
153    {
154      decimalwc = nl_langinfo_wc (_NL_MONETARY_DECIMAL_POINT_WC);
155      if (decimalwc == L_('\0'))
156	decimalwc = nl_langinfo_wc (_NL_NUMERIC_DECIMAL_POINT_WC);
157    }
158  /* The decimal point character must never be zero.  */
159  assert (decimalwc != L_('\0'));
160#else
161  decimalwc = L_('.');
162#endif
163
164  /* Fetch the argument value.	*/
165    {
166      fpnum.value = **(const __float128 **) args[0];
167
168      /* Check for special values: not a number or infinity.  */
169      if (isnanq (fpnum.value))
170	{
171	  negative = fpnum.ieee.negative != 0;
172	  if (isupper (info->spec))
173	    {
174	      special = "NAN";
175	      wspecial = L_("NAN");
176	    }
177	  else
178	    {
179	      special = "nan";
180	      wspecial = L_("nan");
181	    }
182	}
183      else
184	{
185	  if (isinfq (fpnum.value))
186	    {
187	      if (isupper (info->spec))
188		{
189		  special = "INF";
190		  wspecial = L_("INF");
191		}
192	      else
193		{
194		  special = "inf";
195		  wspecial = L_("inf");
196		}
197	    }
198
199	  negative = signbitq (fpnum.value);
200	}
201    }
202
203  if (special)
204    {
205      int width = info->width;
206
207      if (negative || info->showsign || info->space)
208	--width;
209      width -= 3;
210
211      if (!info->left && width > 0)
212	PADN (' ', width);
213
214      if (negative)
215	outchar ('-');
216      else if (info->showsign)
217	outchar ('+');
218      else if (info->space)
219	outchar (' ');
220
221      PRINT (special, wspecial, 3);
222
223      if (info->left && width > 0)
224	PADN (' ', width);
225
226      return done;
227    }
228
229    {
230      /* We have 112 bits of mantissa plus one implicit digit.  Since
231	 112 bits are representable without rest using hexadecimal
232	 digits we use only the implicit digits for the number before
233	 the decimal point.  */
234      uint64_t num0, num1;
235
236      assert (sizeof (long double) == 16);
237
238      num0 = fpnum.ieee.mant_high;
239      num1 = fpnum.ieee.mant_low;
240
241      zero_mantissa = (num0|num1) == 0;
242
243      if (sizeof (unsigned long int) > 6)
244	{
245	  numstr = _itoa_word (num1, numbuf + sizeof numbuf, 16,
246			       info->spec == 'A');
247	  wnumstr = _itowa_word (num1,
248				 wnumbuf + sizeof (wnumbuf) / sizeof (wchar_t),
249				 16, info->spec == 'A');
250	}
251      else
252	{
253	  numstr = _itoa (num1, numbuf + sizeof numbuf, 16,
254			  info->spec == 'A');
255	  wnumstr = _itowa (num1,
256			    wnumbuf + sizeof (wnumbuf) / sizeof (wchar_t),
257			    16, info->spec == 'A');
258	}
259
260      while (numstr > numbuf + (sizeof numbuf - 64 / 4))
261	{
262	  *--numstr = '0';
263	  *--wnumstr = L_('0');
264	}
265
266      if (sizeof (unsigned long int) > 6)
267	{
268	  numstr = _itoa_word (num0, numstr, 16, info->spec == 'A');
269	  wnumstr = _itowa_word (num0, wnumstr, 16, info->spec == 'A');
270	}
271      else
272	{
273	  numstr = _itoa (num0, numstr, 16, info->spec == 'A');
274	  wnumstr = _itowa (num0, wnumstr, 16, info->spec == 'A');
275	}
276
277      /* Fill with zeroes.  */
278      while (numstr > numbuf + (sizeof numbuf - 112 / 4))
279	{
280	  *--wnumstr = L_('0');
281	  *--numstr = '0';
282	}
283
284      leading = fpnum.ieee.exponent == 0 ? '0' : '1';
285
286      exponent = fpnum.ieee.exponent;
287
288      if (exponent == 0)
289	{
290	  if (zero_mantissa)
291	    expnegative = 0;
292	  else
293	    {
294	      /* This is a denormalized number.  */
295	      expnegative = 1;
296	      exponent = IEEE854_FLOAT128_BIAS - 1;
297	    }
298	}
299      else if (exponent >= IEEE854_FLOAT128_BIAS)
300	{
301	  expnegative = 0;
302	  exponent -= IEEE854_FLOAT128_BIAS;
303	}
304      else
305	{
306	  expnegative = 1;
307	  exponent = -(exponent - IEEE854_FLOAT128_BIAS);
308	}
309    }
310
311  /* Look for trailing zeroes.  */
312  if (! zero_mantissa)
313    {
314      wnumend = &wnumbuf[sizeof wnumbuf / sizeof wnumbuf[0]];
315      numend = &numbuf[sizeof numbuf / sizeof numbuf[0]];
316      while (wnumend[-1] == L_('0'))
317	{
318	  --wnumend;
319	  --numend;
320	}
321
322      do_round_away = false;
323
324      if (precision != -1 && precision < numend - numstr)
325	{
326	  char last_digit = precision > 0 ? numstr[precision - 1] : leading;
327	  char next_digit = numstr[precision];
328	  int last_digit_value = (last_digit >= 'A' && last_digit <= 'F'
329				  ? last_digit - 'A' + 10
330				  : (last_digit >= 'a' && last_digit <= 'f'
331				     ? last_digit - 'a' + 10
332				     : last_digit - '0'));
333	  int next_digit_value = (next_digit >= 'A' && next_digit <= 'F'
334				  ? next_digit - 'A' + 10
335				  : (next_digit >= 'a' && next_digit <= 'f'
336				     ? next_digit - 'a' + 10
337				     : next_digit - '0'));
338	  bool more_bits = ((next_digit_value & 7) != 0
339			    || precision + 1 < numend - numstr);
340#ifdef HAVE_FENV_H
341	  int rounding_mode = get_rounding_mode ();
342	  do_round_away = round_away (negative, last_digit_value & 1,
343				      next_digit_value >= 8, more_bits,
344				      rounding_mode);
345#endif
346	}
347
348      if (precision == -1)
349	precision = numend - numstr;
350      else if (do_round_away)
351	{
352	  /* Round up.  */
353	  int cnt = precision;
354	  while (--cnt >= 0)
355	    {
356	      char ch = numstr[cnt];
357	      /* We assume that the digits and the letters are ordered
358		 like in ASCII.  This is true for the rest of GNU, too.  */
359	      if (ch == '9')
360		{
361		  wnumstr[cnt] = (wchar_t) info->spec;
362		  numstr[cnt] = info->spec;	/* This is tricky,
363		  				   think about it!  */
364		  break;
365		}
366	      else if (tolower (ch) < 'f')
367		{
368		  ++numstr[cnt];
369		  ++wnumstr[cnt];
370		  break;
371		}
372	      else
373		{
374		  numstr[cnt] = '0';
375		  wnumstr[cnt] = L_('0');
376		}
377	    }
378	  if (cnt < 0)
379	    {
380	      /* The mantissa so far was fff...f  Now increment the
381		 leading digit.  Here it is again possible that we
382		 get an overflow.  */
383	      if (leading == '9')
384		leading = info->spec;
385	      else if (tolower (leading) < 'f')
386		++leading;
387	      else
388		{
389		  leading = '1';
390		  if (expnegative)
391		    {
392		      exponent -= 4;
393		      if (exponent <= 0)
394			{
395			  exponent = -exponent;
396			  expnegative = 0;
397			}
398		    }
399		  else
400		    exponent += 4;
401		}
402	    }
403	}
404    }
405  else
406    {
407      if (precision == -1)
408	precision = 0;
409      numend = numstr;
410      wnumend = wnumstr;
411    }
412
413  /* Now we can compute the exponent string.  */
414  expstr = _itoa_word (exponent, expbuf + sizeof expbuf, 10, 0);
415  wexpstr = _itowa_word (exponent,
416			 wexpbuf + sizeof wexpbuf / sizeof (wchar_t), 10, 0);
417
418  /* Now we have all information to compute the size.  */
419  width -= ((negative || info->showsign || info->space)
420	    /* Sign.  */
421	    + 2    + 1 + 0 + precision + 1 + 1
422	    /* 0x    h   .   hhh         P   ExpoSign.  */
423	    + ((expbuf + sizeof expbuf) - expstr));
424	    /* Exponent.  */
425
426  /* Count the decimal point.
427     A special case when the mantissa or the precision is zero and the `#'
428     is not given.  In this case we must not print the decimal point.  */
429  if (precision > 0 || info->alt)
430    width -= wide ? 1 : strlen (decimal);
431
432  if (!info->left && info->pad != '0' && width > 0)
433    PADN (' ', width);
434
435  if (negative)
436    outchar ('-');
437  else if (info->showsign)
438    outchar ('+');
439  else if (info->space)
440    outchar (' ');
441
442  outchar ('0');
443  if ('X' - 'A' == 'x' - 'a')
444    outchar (info->spec + ('x' - 'a'));
445  else
446    outchar (info->spec == 'A' ? 'X' : 'x');
447
448  if (!info->left && info->pad == '0' && width > 0)
449    PADN ('0', width);
450
451  outchar (leading);
452
453  if (precision > 0 || info->alt)
454    {
455      const wchar_t *wtmp = &decimalwc;
456      PRINT (decimal, wtmp, wide ? 1 : strlen (decimal));
457    }
458
459  if (precision > 0)
460    {
461      ssize_t tofill = precision - (numend - numstr);
462      PRINT (numstr, wnumstr, MIN (numend - numstr, precision));
463      if (tofill > 0)
464	PADN ('0', tofill);
465    }
466
467  if ('P' - 'A' == 'p' - 'a')
468    outchar (info->spec + ('p' - 'a'));
469  else
470    outchar (info->spec == 'A' ? 'P' : 'p');
471
472  outchar (expnegative ? '-' : '+');
473
474  PRINT (expstr, wexpstr, (expbuf + sizeof expbuf) - expstr);
475
476  if (info->left && info->pad != '0' && width > 0)
477    PADN (info->pad, width);
478
479  return done;
480}
481