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 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 = (((unsigned long long int) fpnum.ieee.mantissa0) << 32 239 | fpnum.ieee.mantissa1); 240 num1 = (((unsigned long long int) fpnum.ieee.mantissa2) << 32 241 | fpnum.ieee.mantissa3); 242 243 zero_mantissa = (num0|num1) == 0; 244 245 if (sizeof (unsigned long int) > 6) 246 { 247 numstr = _itoa_word (num1, numbuf + sizeof numbuf, 16, 248 info->spec == 'A'); 249 wnumstr = _itowa_word (num1, 250 wnumbuf + sizeof (wnumbuf) / sizeof (wchar_t), 251 16, info->spec == 'A'); 252 } 253 else 254 { 255 numstr = _itoa (num1, numbuf + sizeof numbuf, 16, 256 info->spec == 'A'); 257 wnumstr = _itowa (num1, 258 wnumbuf + sizeof (wnumbuf) / sizeof (wchar_t), 259 16, info->spec == 'A'); 260 } 261 262 while (numstr > numbuf + (sizeof numbuf - 64 / 4)) 263 { 264 *--numstr = '0'; 265 *--wnumstr = L_('0'); 266 } 267 268 if (sizeof (unsigned long int) > 6) 269 { 270 numstr = _itoa_word (num0, numstr, 16, info->spec == 'A'); 271 wnumstr = _itowa_word (num0, wnumstr, 16, info->spec == 'A'); 272 } 273 else 274 { 275 numstr = _itoa (num0, numstr, 16, info->spec == 'A'); 276 wnumstr = _itowa (num0, wnumstr, 16, info->spec == 'A'); 277 } 278 279 /* Fill with zeroes. */ 280 while (numstr > numbuf + (sizeof numbuf - 112 / 4)) 281 { 282 *--wnumstr = L_('0'); 283 *--numstr = '0'; 284 } 285 286 leading = fpnum.ieee.exponent == 0 ? '0' : '1'; 287 288 exponent = fpnum.ieee.exponent; 289 290 if (exponent == 0) 291 { 292 if (zero_mantissa) 293 expnegative = 0; 294 else 295 { 296 /* This is a denormalized number. */ 297 expnegative = 1; 298 exponent = IEEE854_FLOAT128_BIAS - 1; 299 } 300 } 301 else if (exponent >= IEEE854_FLOAT128_BIAS) 302 { 303 expnegative = 0; 304 exponent -= IEEE854_FLOAT128_BIAS; 305 } 306 else 307 { 308 expnegative = 1; 309 exponent = -(exponent - IEEE854_FLOAT128_BIAS); 310 } 311 } 312 313 /* Look for trailing zeroes. */ 314 if (! zero_mantissa) 315 { 316 wnumend = &wnumbuf[sizeof wnumbuf / sizeof wnumbuf[0]]; 317 numend = &numbuf[sizeof numbuf / sizeof numbuf[0]]; 318 while (wnumend[-1] == L_('0')) 319 { 320 --wnumend; 321 --numend; 322 } 323 324 do_round_away = false; 325 326 if (precision != -1 && precision < numend - numstr) 327 { 328 char last_digit = precision > 0 ? numstr[precision - 1] : leading; 329 char next_digit = numstr[precision]; 330 int last_digit_value = (last_digit >= 'A' && last_digit <= 'F' 331 ? last_digit - 'A' + 10 332 : (last_digit >= 'a' && last_digit <= 'f' 333 ? last_digit - 'a' + 10 334 : last_digit - '0')); 335 int next_digit_value = (next_digit >= 'A' && next_digit <= 'F' 336 ? next_digit - 'A' + 10 337 : (next_digit >= 'a' && next_digit <= 'f' 338 ? next_digit - 'a' + 10 339 : next_digit - '0')); 340 bool more_bits = ((next_digit_value & 7) != 0 341 || precision + 1 < numend - numstr); 342 #ifdef HAVE_FENV_H 343 int rounding_mode = get_rounding_mode (); 344 do_round_away = round_away (negative, last_digit_value & 1, 345 next_digit_value >= 8, more_bits, 346 rounding_mode); 347 #endif 348 } 349 350 if (precision == -1) 351 precision = numend - numstr; 352 else if (do_round_away) 353 { 354 /* Round up. */ 355 int cnt = precision; 356 while (--cnt >= 0) 357 { 358 char ch = numstr[cnt]; 359 /* We assume that the digits and the letters are ordered 360 like in ASCII. This is true for the rest of GNU, too. */ 361 if (ch == '9') 362 { 363 wnumstr[cnt] = (wchar_t) info->spec; 364 numstr[cnt] = info->spec; /* This is tricky, 365 think about it! */ 366 break; 367 } 368 else if (tolower (ch) < 'f') 369 { 370 ++numstr[cnt]; 371 ++wnumstr[cnt]; 372 break; 373 } 374 else 375 { 376 numstr[cnt] = '0'; 377 wnumstr[cnt] = L_('0'); 378 } 379 } 380 if (cnt < 0) 381 { 382 /* The mantissa so far was fff...f Now increment the 383 leading digit. Here it is again possible that we 384 get an overflow. */ 385 if (leading == '9') 386 leading = info->spec; 387 else if (tolower (leading) < 'f') 388 ++leading; 389 else 390 { 391 leading = '1'; 392 if (expnegative) 393 { 394 exponent -= 4; 395 if (exponent <= 0) 396 { 397 exponent = -exponent; 398 expnegative = 0; 399 } 400 } 401 else 402 exponent += 4; 403 } 404 } 405 } 406 } 407 else 408 { 409 if (precision == -1) 410 precision = 0; 411 numend = numstr; 412 wnumend = wnumstr; 413 } 414 415 /* Now we can compute the exponent string. */ 416 expstr = _itoa_word (exponent, expbuf + sizeof expbuf, 10, 0); 417 wexpstr = _itowa_word (exponent, 418 wexpbuf + sizeof wexpbuf / sizeof (wchar_t), 10, 0); 419 420 /* Now we have all information to compute the size. */ 421 width -= ((negative || info->showsign || info->space) 422 /* Sign. */ 423 + 2 + 1 + 0 + precision + 1 + 1 424 /* 0x h . hhh P ExpoSign. */ 425 + ((expbuf + sizeof expbuf) - expstr)); 426 /* Exponent. */ 427 428 /* Count the decimal point. 429 A special case when the mantissa or the precision is zero and the `#' 430 is not given. In this case we must not print the decimal point. */ 431 if (precision > 0 || info->alt) 432 width -= wide ? 1 : strlen (decimal); 433 434 if (!info->left && info->pad != '0' && width > 0) 435 PADN (' ', width); 436 437 if (negative) 438 outchar ('-'); 439 else if (info->showsign) 440 outchar ('+'); 441 else if (info->space) 442 outchar (' '); 443 444 outchar ('0'); 445 if ('X' - 'A' == 'x' - 'a') 446 outchar (info->spec + ('x' - 'a')); 447 else 448 outchar (info->spec == 'A' ? 'X' : 'x'); 449 450 if (!info->left && info->pad == '0' && width > 0) 451 PADN ('0', width); 452 453 outchar (leading); 454 455 if (precision > 0 || info->alt) 456 { 457 const wchar_t *wtmp = &decimalwc; 458 PRINT (decimal, wtmp, wide ? 1 : strlen (decimal)); 459 } 460 461 if (precision > 0) 462 { 463 ssize_t tofill = precision - (numend - numstr); 464 PRINT (numstr, wnumstr, MIN (numend - numstr, precision)); 465 if (tofill > 0) 466 PADN ('0', tofill); 467 } 468 469 if ('P' - 'A' == 'p' - 'a') 470 outchar (info->spec + ('p' - 'a')); 471 else 472 outchar (info->spec == 'A' ? 'P' : 'p'); 473 474 outchar (expnegative ? '-' : '+'); 475 476 PRINT (expstr, wexpstr, (expbuf + sizeof expbuf) - expstr); 477 478 if (info->left && info->pad != '0' && width > 0) 479 PADN (info->pad, width); 480 481 return done; 482 } 483