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 68 int 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 memcpy (&fpnum.value, *(const void *const *) args[0], 167 sizeof (fpnum.value)); 168 169 /* Check for special values: not a number or infinity. */ 170 if (isnanq (fpnum.value)) 171 { 172 negative = fpnum.ieee.negative != 0; 173 if (isupper (info->spec)) 174 { 175 special = "NAN"; 176 wspecial = L_("NAN"); 177 } 178 else 179 { 180 special = "nan"; 181 wspecial = L_("nan"); 182 } 183 } 184 else 185 { 186 if (isinfq (fpnum.value)) 187 { 188 if (isupper (info->spec)) 189 { 190 special = "INF"; 191 wspecial = L_("INF"); 192 } 193 else 194 { 195 special = "inf"; 196 wspecial = L_("inf"); 197 } 198 } 199 200 negative = signbitq (fpnum.value); 201 } 202 } 203 204 if (special) 205 { 206 int width = info->width; 207 208 if (negative || info->showsign || info->space) 209 --width; 210 width -= 3; 211 212 if (!info->left && width > 0) 213 PADN (' ', width); 214 215 if (negative) 216 outchar ('-'); 217 else if (info->showsign) 218 outchar ('+'); 219 else if (info->space) 220 outchar (' '); 221 222 PRINT (special, wspecial, 3); 223 224 if (info->left && width > 0) 225 PADN (' ', width); 226 227 return done; 228 } 229 230 { 231 /* We have 112 bits of mantissa plus one implicit digit. Since 232 112 bits are representable without rest using hexadecimal 233 digits we use only the implicit digits for the number before 234 the decimal point. */ 235 uint64_t num0, num1; 236 237 assert (sizeof (long double) == 16); 238 239 num0 = (((unsigned long long int) fpnum.ieee.mantissa0) << 32 240 | fpnum.ieee.mantissa1); 241 num1 = (((unsigned long long int) fpnum.ieee.mantissa2) << 32 242 | fpnum.ieee.mantissa3); 243 244 zero_mantissa = (num0|num1) == 0; 245 246 if (sizeof (unsigned long int) > 6) 247 { 248 numstr = _itoa_word (num1, numbuf + sizeof numbuf, 16, 249 info->spec == 'A'); 250 wnumstr = _itowa_word (num1, 251 wnumbuf + sizeof (wnumbuf) / sizeof (wchar_t), 252 16, info->spec == 'A'); 253 } 254 else 255 { 256 numstr = _itoa (num1, numbuf + sizeof numbuf, 16, 257 info->spec == 'A'); 258 wnumstr = _itowa (num1, 259 wnumbuf + sizeof (wnumbuf) / sizeof (wchar_t), 260 16, info->spec == 'A'); 261 } 262 263 while (numstr > numbuf + (sizeof numbuf - 64 / 4)) 264 { 265 *--numstr = '0'; 266 *--wnumstr = L_('0'); 267 } 268 269 if (sizeof (unsigned long int) > 6) 270 { 271 numstr = _itoa_word (num0, numstr, 16, info->spec == 'A'); 272 wnumstr = _itowa_word (num0, wnumstr, 16, info->spec == 'A'); 273 } 274 else 275 { 276 numstr = _itoa (num0, numstr, 16, info->spec == 'A'); 277 wnumstr = _itowa (num0, wnumstr, 16, info->spec == 'A'); 278 } 279 280 /* Fill with zeroes. */ 281 while (numstr > numbuf + (sizeof numbuf - 112 / 4)) 282 { 283 *--wnumstr = L_('0'); 284 *--numstr = '0'; 285 } 286 287 leading = fpnum.ieee.exponent == 0 ? '0' : '1'; 288 289 exponent = fpnum.ieee.exponent; 290 291 if (exponent == 0) 292 { 293 if (zero_mantissa) 294 expnegative = 0; 295 else 296 { 297 /* This is a denormalized number. */ 298 expnegative = 1; 299 exponent = IEEE854_FLOAT128_BIAS - 1; 300 } 301 } 302 else if (exponent >= IEEE854_FLOAT128_BIAS) 303 { 304 expnegative = 0; 305 exponent -= IEEE854_FLOAT128_BIAS; 306 } 307 else 308 { 309 expnegative = 1; 310 exponent = -(exponent - IEEE854_FLOAT128_BIAS); 311 } 312 } 313 314 /* Look for trailing zeroes. */ 315 if (! zero_mantissa) 316 { 317 wnumend = &wnumbuf[sizeof wnumbuf / sizeof wnumbuf[0]]; 318 numend = &numbuf[sizeof numbuf / sizeof numbuf[0]]; 319 while (wnumend[-1] == L_('0')) 320 { 321 --wnumend; 322 --numend; 323 } 324 325 do_round_away = false; 326 327 if (precision != -1 && precision < numend - numstr) 328 { 329 char last_digit = precision > 0 ? numstr[precision - 1] : leading; 330 char next_digit = numstr[precision]; 331 int last_digit_value = (last_digit >= 'A' && last_digit <= 'F' 332 ? last_digit - 'A' + 10 333 : (last_digit >= 'a' && last_digit <= 'f' 334 ? last_digit - 'a' + 10 335 : last_digit - '0')); 336 int next_digit_value = (next_digit >= 'A' && next_digit <= 'F' 337 ? next_digit - 'A' + 10 338 : (next_digit >= 'a' && next_digit <= 'f' 339 ? next_digit - 'a' + 10 340 : next_digit - '0')); 341 bool more_bits = ((next_digit_value & 7) != 0 342 || precision + 1 < numend - numstr); 343 #ifdef HAVE_FENV_H 344 int rounding_mode = get_rounding_mode (); 345 do_round_away = round_away (negative, last_digit_value & 1, 346 next_digit_value >= 8, more_bits, 347 rounding_mode); 348 #endif 349 } 350 351 if (precision == -1) 352 precision = numend - numstr; 353 else if (do_round_away) 354 { 355 /* Round up. */ 356 int cnt = precision; 357 while (--cnt >= 0) 358 { 359 char ch = numstr[cnt]; 360 /* We assume that the digits and the letters are ordered 361 like in ASCII. This is true for the rest of GNU, too. */ 362 if (ch == '9') 363 { 364 wnumstr[cnt] = (wchar_t) info->spec; 365 numstr[cnt] = info->spec; /* This is tricky, 366 think about it! */ 367 break; 368 } 369 else if (tolower (ch) < 'f') 370 { 371 ++numstr[cnt]; 372 ++wnumstr[cnt]; 373 break; 374 } 375 else 376 { 377 numstr[cnt] = '0'; 378 wnumstr[cnt] = L_('0'); 379 } 380 } 381 if (cnt < 0) 382 { 383 /* The mantissa so far was fff...f Now increment the 384 leading digit. Here it is again possible that we 385 get an overflow. */ 386 if (leading == '9') 387 leading = info->spec; 388 else if (tolower (leading) < 'f') 389 ++leading; 390 else 391 { 392 leading = '1'; 393 if (expnegative) 394 { 395 exponent -= 4; 396 if (exponent <= 0) 397 { 398 exponent = -exponent; 399 expnegative = 0; 400 } 401 } 402 else 403 exponent += 4; 404 } 405 } 406 } 407 } 408 else 409 { 410 if (precision == -1) 411 precision = 0; 412 numend = numstr; 413 wnumend = wnumstr; 414 } 415 416 /* Now we can compute the exponent string. */ 417 expstr = _itoa_word (exponent, expbuf + sizeof expbuf, 10, 0); 418 wexpstr = _itowa_word (exponent, 419 wexpbuf + sizeof wexpbuf / sizeof (wchar_t), 10, 0); 420 421 /* Now we have all information to compute the size. */ 422 width -= ((negative || info->showsign || info->space) 423 /* Sign. */ 424 + 2 + 1 + 0 + precision + 1 + 1 425 /* 0x h . hhh P ExpoSign. */ 426 + ((expbuf + sizeof expbuf) - expstr)); 427 /* Exponent. */ 428 429 /* Count the decimal point. 430 A special case when the mantissa or the precision is zero and the `#' 431 is not given. In this case we must not print the decimal point. */ 432 if (precision > 0 || info->alt) 433 width -= wide ? 1 : strlen (decimal); 434 435 if (!info->left && info->pad != '0' && width > 0) 436 PADN (' ', width); 437 438 if (negative) 439 outchar ('-'); 440 else if (info->showsign) 441 outchar ('+'); 442 else if (info->space) 443 outchar (' '); 444 445 outchar ('0'); 446 if ('X' - 'A' == 'x' - 'a') 447 outchar (info->spec + ('x' - 'a')); 448 else 449 outchar (info->spec == 'A' ? 'X' : 'x'); 450 451 if (!info->left && info->pad == '0' && width > 0) 452 PADN ('0', width); 453 454 outchar (leading); 455 456 if (precision > 0 || info->alt) 457 { 458 const wchar_t *wtmp = &decimalwc; 459 PRINT (decimal, wtmp, wide ? 1 : strlen (decimal)); 460 } 461 462 if (precision > 0) 463 { 464 ssize_t tofill = precision - (numend - numstr); 465 PRINT (numstr, wnumstr, MIN (numend - numstr, precision)); 466 if (tofill > 0) 467 PADN ('0', tofill); 468 } 469 470 if ('P' - 'A' == 'p' - 'a') 471 outchar (info->spec + ('p' - 'a')); 472 else 473 outchar (info->spec == 'A' ? 'P' : 'p'); 474 475 outchar (expnegative ? '-' : '+'); 476 477 PRINT (expstr, wexpstr, (expbuf + sizeof expbuf) - expstr); 478 479 if (info->left && info->pad != '0' && width > 0) 480 PADN (info->pad, width); 481 482 return done; 483 } 484