1 /* Print floating point number in hexadecimal notation according to
3 Copyright (C) 1997 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
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 not,
19 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
30 #include <locale/localeinfo.h>
32 /* #define NDEBUG 1*/ /* Undefine this for debugging assertions. */
35 /* This defines make it possible to use the same code for GNU C library and
36 the GNU I/O library. */
39 # define PUT(f, s, n) _IO_sputn (f, s, n)
40 # define PAD(f, c, n) _IO_padn (f, c, n)
41 /* We use this file GNU C library and GNU I/O library. So make
44 # define putc(c, f) _IO_putc_unlocked (c, f)
45 # define size_t _IO_size_t
46 # define FILE _IO_FILE
47 #else /* ! USE_IN_LIBIO */
48 # define PUT(f, s, n) fwrite (s, 1, n, f)
49 # define PAD(f, c, n) __printf_pad (f, c, n)
50 ssize_t __printf_pad
__P ((FILE *, char pad
, int n
)); /* In vfprintf.c. */
51 #endif /* USE_IN_LIBIO */
53 /* Macros for doing the actual output. */
58 register const int outc = (ch); \
59 if (putc (outc, fp) == EOF) \
64 #define PRINT(ptr, len) \
68 const char *cp = (ptr); \
69 while (outlen-- > 0) \
73 #define PADN(ch, len) \
76 if (PAD (fp, ch, len) != len) \
83 # define MIN(a,b) ((a)<(b)?(a):(b))
88 __printf_fphex (FILE *fp
,
89 const struct printf_info
*info
,
90 const void *const *args
)
92 /* The floating-point value to output. */
95 union ieee754_double dbl
;
96 union ieee854_long_double ldbl
;
100 /* Locale-dependent representation of decimal point. */
103 /* "NaN" or "Inf" for the special cases. */
104 const char *special
= NULL
;
106 /* Buffer for the generated number string for the mantissa. The
107 maximal size for the mantissa is 64 bits. */
113 /* The maximal exponent of two in decimal notation has 5 digits. */
119 /* Non-zero is mantissa is zero. */
122 /* The leading digit before the decimal point. */
126 int precision
= info
->prec
;
129 int width
= info
->width
;
131 /* Number of characters written. */
135 /* Figure out the decimal point character. */
136 if (info
->extra
== 0)
138 if (mbtowc (&decimal
, _NL_CURRENT (LC_NUMERIC
, DECIMAL_POINT
),
139 strlen (_NL_CURRENT (LC_NUMERIC
, DECIMAL_POINT
))) <= 0)
140 decimal
= (wchar_t) *_NL_CURRENT (LC_NUMERIC
, DECIMAL_POINT
);
144 if (mbtowc (&decimal
, _NL_CURRENT (LC_MONETARY
, MON_DECIMAL_POINT
),
145 strlen (_NL_CURRENT (LC_MONETARY
, MON_DECIMAL_POINT
))) <= 0)
146 decimal
= (wchar_t) *_NL_CURRENT (LC_MONETARY
, MON_DECIMAL_POINT
);
148 /* Give default value. */
149 if (decimal
== L
'\0')
153 /* Fetch the argument value. */
154 if (info
->is_long_double
&& sizeof (long double) > sizeof (double))
156 fpnum
.ldbl
.d
= *(const long double *) args
[0];
158 /* Check for special values: not a number or infinity. */
159 if (__isnanl (fpnum
.ldbl
.d
))
161 special
= isupper (info
->spec
) ? "NAN" : "nan";
166 if (__isinfl (fpnum
.ldbl
.d
))
167 special
= isupper (info
->spec
) ? "INF" : "inf";
169 negative
= signbit (fpnum
.ldbl
.d
);
174 fpnum
.dbl
.d
= *(const double *) args
[0];
176 /* Check for special values: not a number or infinity. */
177 if (__isnan (fpnum
.dbl
.d
))
179 special
= isupper (info
->spec
) ? "NAN" : "nan";
184 if (__isinf (fpnum
.dbl
.d
))
185 special
= isupper (info
->spec
) ? "INF" : "inf";
187 negative
= signbit (fpnum
.dbl
.d
);
193 int width
= info
->width
;
195 if (negative
|| info
->showsign
|| info
->space
)
199 if (!info
->left
&& width
> 0)
204 else if (info
->showsign
)
206 else if (info
->space
)
211 if (info
->left
&& width
> 0)
217 /* We are handling here only 64 and 80 bit IEEE foating point
219 if (info
->is_long_double
== 0 || sizeof (double) == sizeof (long double))
221 /* We have 52 bits of mantissa plus one implicit digit. Since
222 52 bits are representable without rest using hexadecimal
223 digits we use only the implicit digits for the number before
224 the decimal point. */
225 unsigned long long int num
;
227 num
= (((unsigned long long int) fpnum
.dbl
.ieee
.mantissa0
) << 32
228 | fpnum
.dbl
.ieee
.mantissa1
);
230 zero_mantissa
= num
== 0;
232 if (sizeof (unsigned long int) > 6)
233 numstr
= _itoa_word (num
, numbuf
+ sizeof numbuf
, 16,
236 numstr
= _itoa (num
, numbuf
+ sizeof numbuf
, 16,
239 /* Fill with zeroes. */
240 while (numstr
> numbuf
+ (sizeof numbuf
- 52 / 4))
243 leading
= fpnum
.dbl
.ieee
.exponent
== 0 ? '0' : '1';
245 exponent
= fpnum
.dbl
.ieee
.exponent
;
247 if (exponent
== 0 ? !zero_mantissa
: exponent
< IEEE754_DOUBLE_BIAS
)
250 exponent
= -(exponent
- IEEE754_DOUBLE_BIAS
);
256 exponent
-= IEEE754_DOUBLE_BIAS
;
261 /* The "strange" 80 bit format on ix86 and m68k has an explicit
262 leading digit in the 64 bit mantissa. */
263 unsigned long long int num
;
265 assert (sizeof (long double) == 12);
267 num
= (((unsigned long long int) fpnum
.ldbl
.ieee
.mantissa0
) << 32
268 | fpnum
.ldbl
.ieee
.mantissa1
);
270 zero_mantissa
= num
== 0;
272 if (sizeof (unsigned long int) > 6)
273 numstr
= _itoa_word (num
, numbuf
+ sizeof numbuf
, 16,
276 numstr
= _itoa (num
, numbuf
+ sizeof numbuf
, 16, info
->spec
== 'A');
278 /* Fill with zeroes. */
279 while (numstr
> numbuf
+ (sizeof numbuf
- 64 / 4))
282 /* We use a full nibble for the leading digit. */
285 /* We have 3 bits from the mantissa in the leading nibble. */
286 exponent
= fpnum
.ldbl
.ieee
.exponent
;
288 if (exponent
== 0 ? !zero_mantissa
289 : exponent
< IEEE854_LONG_DOUBLE_BIAS
+ 3)
292 exponent
= -(exponent
- (IEEE854_LONG_DOUBLE_BIAS
+ 3));
298 exponent
-= IEEE854_LONG_DOUBLE_BIAS
+ 3;
302 /* Look for trailing zeroes. */
305 numend
= numbuf
+ sizeof numbuf
;
306 while (numend
[-1] == '0')
310 precision
= numend
- numstr
;
311 else if (precision
< numend
- numstr
312 && (numstr
[precision
] > '8'
313 || (('A' < '0' || 'a' < '0')
314 && numstr
[precision
] < '0')
315 || (numstr
[precision
] == '8'
316 && (precision
+ 1 < numend
- numstr
319 && ((numstr
[precision
- 1] & 1)
320 ^ (isdigit (numstr
[precision
- 1]) == 0)))
323 ^ (isdigit (leading
) == 0)))))))
329 char ch
= numstr
[cnt
];
330 /* We assume that the digits and the letters are ordered
331 like in ASCII. This is true for the rest of GNU, too. */
334 numstr
[cnt
] = info
->spec
; /* This is tricky,
338 else if (tolower (ch
) < 'f')
348 /* The mantissa so far was fff...f Now increment the
349 leading digit. Here it is again possible that we
352 leading
= info
->spec
;
353 else if (tolower (leading
) < 'f')
373 /* Now we can compute the exponent string. */
374 expstr
= _itoa_word (exponent
, expbuf
+ sizeof expbuf
, 10, 0);
376 /* Now we have all information to compute the size. */
377 width
-= ((negative
|| info
->showsign
|| info
->space
)
379 + 2 + 1 + 1 + precision
+ 1 + 1
380 /* 0x h . hhh P ExpoSign. */
381 + ((expbuf
+ sizeof expbuf
) - expstr
));
384 /* A special case if when the mantissa is zero and the `#' is not
385 given. In this case we must not print the decimal point. */
386 if (zero_mantissa
&& precision
== 0 && !info
->alt
)
387 ++width
; /* This nihilates the +1 for the decimal-point
388 character in the following equation. */
390 if (!info
->left
&& width
> 0)
395 else if (info
->showsign
)
397 else if (info
->space
)
401 outchar (info
->spec
== 'A' ? 'X' : 'x');
404 if (!zero_mantissa
|| precision
> 0 || info
->alt
)
407 if (!zero_mantissa
|| precision
> 0)
409 PRINT (numstr
, MIN (numend
- numstr
, precision
));
410 if (precision
> numend
- numstr
)
411 PADN ('0', precision
- (numend
- numstr
));
414 if (info
->left
&& info
->pad
== '0' && width
> 0)
417 outchar (info
->spec
== 'A' ? 'P' : 'p');
419 outchar (expnegative
? '-' : '+');
421 PRINT (expstr
, (expbuf
+ sizeof expbuf
) - expstr
);
423 if (info
->left
&& info
->pad
!= '0' && width
> 0)
424 PADN (info
->pad
, width
);