vfprintf.c revision 1.55
1 /* $NetBSD: vfprintf.c,v 1.55 2007/01/26 00:37:30 cbiere Exp $ */ 2 3 /*- 4 * Copyright (c) 1990 The Regents of the University of California. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Chris Torek. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 #if defined(LIBC_SCCS) && !defined(lint) 37 #if 0 38 static char *sccsid = "@(#)vfprintf.c 5.50 (Berkeley) 12/16/92"; 39 #else 40 __RCSID("$NetBSD: vfprintf.c,v 1.55 2007/01/26 00:37:30 cbiere Exp $"); 41 #endif 42 #endif /* LIBC_SCCS and not lint */ 43 44 /* 45 * Actual printf innards. 46 * 47 * This code is large and complicated... 48 */ 49 50 #include "namespace.h" 51 #include <sys/types.h> 52 53 #include <assert.h> 54 #include <errno.h> 55 #include <stdarg.h> 56 #include <stddef.h> 57 #include <stdint.h> 58 #include <stdio.h> 59 #include <stdlib.h> 60 #include <string.h> 61 #include <wchar.h> 62 #include <limits.h> 63 64 #include "reentrant.h" 65 #include "local.h" 66 #include "fvwrite.h" 67 #include "extern.h" 68 69 static int __sprint __P((FILE *, struct __suio *)); 70 static int __sbprintf __P((FILE *, const char *, va_list)) 71 __attribute__((__format__(__printf__, 2, 0))); 72 73 /* 74 * Flush out all the vectors defined by the given uio, 75 * then reset it so that it can be reused. 76 */ 77 /* NB: async-signal-safe when fp->_flags & __SAFE */ 78 static int 79 __sprint(fp, uio) 80 FILE *fp; 81 struct __suio *uio; 82 { 83 int err; 84 85 _DIAGASSERT(fp != NULL); 86 _DIAGASSERT(uio != NULL); 87 88 if (uio->uio_resid == 0) { 89 uio->uio_iovcnt = 0; 90 return (0); 91 } 92 err = __sfvwrite(fp, uio); 93 uio->uio_resid = 0; 94 uio->uio_iovcnt = 0; 95 return (err); 96 } 97 98 /* 99 * Helper function for `fprintf to unbuffered unix file': creates a 100 * temporary buffer. We only work on write-only files; this avoids 101 * worries about ungetc buffers and so forth. 102 */ 103 static int 104 __sbprintf(fp, fmt, ap) 105 FILE *fp; 106 const char *fmt; 107 va_list ap; 108 { 109 int ret; 110 FILE fake; 111 struct __sfileext fakeext; 112 unsigned char buf[BUFSIZ]; 113 114 _DIAGASSERT(fp != NULL); 115 _DIAGASSERT(fmt != NULL); 116 117 _FILEEXT_SETUP(&fake, &fakeext); 118 119 /* copy the important variables */ 120 fake._flags = fp->_flags & ~__SNBF; 121 fake._file = fp->_file; 122 fake._cookie = fp->_cookie; 123 fake._write = fp->_write; 124 125 /* set up the buffer */ 126 fake._bf._base = fake._p = buf; 127 fake._bf._size = fake._w = sizeof(buf); 128 fake._lbfsize = 0; /* not actually used, but Just In Case */ 129 130 /* do the work, then copy any error status */ 131 ret = vfprintf(&fake, fmt, ap); 132 if (ret >= 0 && fflush(&fake)) 133 ret = -1; 134 if (fake._flags & __SERR) 135 fp->_flags |= __SERR; 136 return (ret); 137 } 138 139 140 #ifndef NO_FLOATING_POINT 141 #include <locale.h> 142 #include <math.h> 143 #include "floatio.h" 144 145 #define BUF (MAXEXP+MAXFRACT+1) /* + decimal point */ 146 #define DEFPREC 6 147 148 static char *cvt __P((double, int, int, char *, int *, int, int *)); 149 static int exponent __P((char *, int, int)); 150 151 #else /* FLOATING_POINT */ 152 153 #define BUF 40 154 155 #endif /* NO_FLOATING_POINT */ 156 157 /* 158 * Macros for converting digits to letters and vice versa 159 */ 160 #define to_digit(c) ((c) - '0') 161 #define is_digit(c) ((unsigned)to_digit(c) <= 9) 162 #define to_char(n) ((char)((n) + '0')) 163 164 /* 165 * Flags used during conversion. 166 */ 167 #define ALT 0x001 /* alternate form */ 168 #define HEXPREFIX 0x002 /* add 0x or 0X prefix */ 169 #define LADJUST 0x004 /* left adjustment */ 170 #define LONGDBL 0x008 /* long double; unimplemented */ 171 #define LONGINT 0x010 /* long integer */ 172 #define QUADINT 0x020 /* quad integer */ 173 #define SHORTINT 0x040 /* short integer */ 174 #define MAXINT 0x080 /* (unsigned) intmax_t */ 175 #define PTRINT 0x100 /* (unsigned) ptrdiff_t */ 176 #define SIZEINT 0x200 /* (signed) size_t */ 177 #define ZEROPAD 0x400 /* zero (as opposed to blank) pad */ 178 #define FPT 0x800 /* Floating point number */ 179 180 static inline int 181 add_digit(int value, int d) 182 { 183 unsigned ret; 184 185 ret = value * 10U + d; 186 if (__predict_false(value > (INT_MAX - 9) / 10)) { 187 if (value > INT_MAX / 10 || ret > INT_MAX) 188 return -1; 189 } 190 return ret; 191 } 192 193 int 194 vfprintf(fp, fmt0, ap) 195 FILE *fp; 196 const char *fmt0; 197 _BSD_VA_LIST_ ap; 198 { 199 int ret; 200 201 FLOCKFILE(fp); 202 ret = __vfprintf_unlocked(fp, fmt0, ap); 203 FUNLOCKFILE(fp); 204 205 return ret; 206 } 207 208 209 210 /* NB: async-signal-safe when fp->_flags & __SAFE */ 211 int 212 __vfprintf_unlocked(fp, fmt0, ap) 213 FILE *fp; 214 const char *fmt0; 215 _BSD_VA_LIST_ ap; 216 { 217 const char *fmt;/* format string */ 218 int ch; /* character from fmt */ 219 int n; /* handy integer (short term usage) */ 220 const char *cp; /* handy char pointer (short term usage) */ 221 char *bp; /* handy char pointer (short term usage) */ 222 struct __siov *iovp;/* for PRINT macro */ 223 int flags; /* flags as above */ 224 int ret; /* return value accumulator */ 225 int width; /* width from format (%8d), or 0 */ 226 int prec; /* precision from format (%.3d), or -1 */ 227 char sign; /* sign prefix (' ', '+', '-', or \0) */ 228 wchar_t wc; 229 mbstate_t ps; 230 #ifndef NO_FLOATING_POINT 231 char *decimal_point = NULL; 232 char softsign; /* temporary negative sign for floats */ 233 double _double; /* double precision arguments %[eEfgG] */ 234 int expt; /* integer value of exponent */ 235 int expsize = 0; /* character count for expstr */ 236 int ndig; /* actual number of digits returned by cvt */ 237 char expstr[7]; /* buffer for exponent string */ 238 char *dtoaresult = NULL; 239 #endif 240 241 #ifdef __GNUC__ /* gcc has builtin quad type (long long) SOS */ 242 #define quad_t long long 243 #define u_quad_t unsigned long long 244 #endif 245 246 #define INTMAX_T intmax_t 247 #define UINTMAX_T uintmax_t 248 249 UINTMAX_T _uintmax; /* integer arguments %[diouxX] */ 250 enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */ 251 int dprec; /* a copy of prec if [diouxX], 0 otherwise */ 252 int realsz; /* field size expanded by dprec */ 253 int size; /* size of converted field or string */ 254 const char *xdigs = NULL;/* digits for [xX] conversion */ 255 #define NIOV 8 256 struct __suio uio; /* output information: summary */ 257 struct __siov iov[NIOV];/* ... and individual io vectors */ 258 char buf[BUF]; /* space for %c, %[diouxX], %[eEfgG] */ 259 char ox[2]; /* space for 0x hex-prefix */ 260 261 /* 262 * Choose PADSIZE to trade efficiency vs. size. If larger printf 263 * fields occur frequently, increase PADSIZE and make the initialisers 264 * below longer. 265 */ 266 #define PADSIZE 16 /* pad chunk size */ 267 static const char blanks[PADSIZE] = 268 {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '}; 269 static const char zeroes[PADSIZE] = 270 {'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'}; 271 272 /* 273 * BEWARE, these `goto error' on error, and PAD uses `n'. 274 */ 275 #define PRINT(ptr, len) { \ 276 iovp->iov_base = __UNCONST(ptr); \ 277 iovp->iov_len = (len); \ 278 uio.uio_resid += (len); \ 279 iovp++; \ 280 if (++uio.uio_iovcnt >= NIOV) { \ 281 if (__sprint(fp, &uio)) \ 282 goto error; \ 283 iovp = iov; \ 284 } \ 285 } 286 #define PAD(howmany, with) { \ 287 if ((n = (howmany)) > 0) { \ 288 while (n > PADSIZE) { \ 289 PRINT(with, PADSIZE); \ 290 n -= PADSIZE; \ 291 } \ 292 PRINT(with, n); \ 293 } \ 294 } 295 #define FLUSH() { \ 296 if (uio.uio_resid && __sprint(fp, &uio)) \ 297 goto error; \ 298 uio.uio_iovcnt = 0; \ 299 iovp = iov; \ 300 } 301 302 /* 303 * To extend shorts properly, we need both signed and unsigned 304 * argument extraction methods. 305 */ 306 #define SARG() \ 307 (flags&MAXINT ? va_arg(ap, intmax_t) : \ 308 flags&PTRINT ? va_arg(ap, ptrdiff_t) : \ 309 flags&SIZEINT ? va_arg(ap, ssize_t) : /* XXX */ \ 310 flags&QUADINT ? va_arg(ap, quad_t) : \ 311 flags&LONGINT ? va_arg(ap, long) : \ 312 flags&SHORTINT ? (long)(short)va_arg(ap, int) : \ 313 (long)va_arg(ap, int)) 314 #define UARG() \ 315 (flags&MAXINT ? va_arg(ap, uintmax_t) : \ 316 flags&PTRINT ? va_arg(ap, uintptr_t) : /* XXX */ \ 317 flags&SIZEINT ? va_arg(ap, size_t) : \ 318 flags&QUADINT ? va_arg(ap, u_quad_t) : \ 319 flags&LONGINT ? va_arg(ap, u_long) : \ 320 flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \ 321 (u_long)va_arg(ap, u_int)) 322 323 _DIAGASSERT(fp != NULL); 324 _DIAGASSERT(fmt0 != NULL); 325 326 _SET_ORIENTATION(fp, -1); 327 328 /* sorry, fprintf(read_only_file, "") returns -1, not 0 */ 329 if (cantwrite(fp)) { 330 errno = EBADF; 331 return (-1); 332 } 333 334 /* optimise fprintf(stderr) (and other unbuffered Unix files) */ 335 if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) && 336 fp->_file >= 0) { 337 ret = __sbprintf(fp, fmt0, ap); 338 return (ret); 339 } 340 341 fmt = fmt0; 342 uio.uio_iov = iovp = iov; 343 uio.uio_resid = 0; 344 uio.uio_iovcnt = 0; 345 ret = 0; 346 347 memset(&ps, 0, sizeof(ps)); 348 349 /* 350 * Scan the format for conversions (`%' character). 351 */ 352 for (;;) { 353 cp = fmt; 354 if (fp->_flags & __SAFE) { 355 for (; *fmt && *fmt != '%'; fmt++) 356 continue; 357 n = *fmt == '%'; 358 } else { 359 while ((n = mbrtowc(&wc, fmt, MB_CUR_MAX, &ps)) > 0) { 360 fmt += n; 361 if (wc == '%') { 362 fmt--; 363 break; 364 } 365 } 366 } 367 if (fmt != cp) { 368 ptrdiff_t m = fmt - cp; 369 if (m < 0 || m > INT_MAX - ret) 370 goto overflow; 371 PRINT(cp, m); 372 ret += m; 373 } 374 if (n <= 0) 375 goto done; 376 fmt++; /* skip over '%' */ 377 378 flags = 0; 379 dprec = 0; 380 width = 0; 381 prec = -1; 382 sign = '\0'; 383 384 rflag: ch = *fmt++; 385 reswitch: switch (ch) { 386 case ' ': 387 /* 388 * ``If the space and + flags both appear, the space 389 * flag will be ignored.'' 390 * -- ANSI X3J11 391 */ 392 if (!sign) 393 sign = ' '; 394 goto rflag; 395 case '#': 396 flags |= ALT; 397 goto rflag; 398 case '*': 399 /* 400 * ``A negative field width argument is taken as a 401 * - flag followed by a positive field width.'' 402 * -- ANSI X3J11 403 * They don't exclude field widths read from args. 404 */ 405 if ((width = va_arg(ap, int)) >= 0) 406 goto rflag; 407 if (-(unsigned)width > INT_MAX) 408 goto overflow; 409 width = -width; 410 /* FALLTHROUGH */ 411 case '-': 412 flags |= LADJUST; 413 goto rflag; 414 case '+': 415 sign = '+'; 416 goto rflag; 417 case '.': 418 if ((ch = *fmt++) == '*') { 419 n = va_arg(ap, int); 420 prec = n < 0 ? -1 : n; 421 goto rflag; 422 } 423 prec = 0; 424 while (ch == '0') 425 ch = *fmt++; 426 while (is_digit(ch)) { 427 prec = add_digit(prec, to_digit(ch)); 428 if (prec < 0) 429 goto overflow; 430 ch = *fmt++; 431 } 432 goto reswitch; 433 case '0': 434 /* 435 * ``Note that 0 is taken as a flag, not as the 436 * beginning of a field width.'' 437 * -- ANSI X3J11 438 */ 439 flags |= ZEROPAD; 440 goto rflag; 441 case '1': case '2': case '3': case '4': 442 case '5': case '6': case '7': case '8': case '9': 443 width = 0; 444 do { 445 width = add_digit(width, to_digit(ch)); 446 if (width < 0) 447 goto overflow; 448 ch = *fmt++; 449 } while (is_digit(ch)); 450 goto reswitch; 451 #ifndef NO_FLOATING_POINT 452 case 'L': 453 flags |= LONGDBL; 454 goto rflag; 455 #endif 456 case 'h': 457 flags |= SHORTINT; 458 goto rflag; 459 case 'j': 460 flags |= MAXINT; 461 goto rflag; 462 case 'l': 463 if (*fmt == 'l') { 464 fmt++; 465 flags |= QUADINT; 466 } else { 467 flags |= LONGINT; 468 } 469 goto rflag; 470 case 'q': 471 flags |= QUADINT; 472 goto rflag; 473 case 't': 474 flags |= PTRINT; 475 goto rflag; 476 case 'z': 477 flags |= SIZEINT; 478 goto rflag; 479 case 'c': 480 *buf = va_arg(ap, int); 481 cp = buf; 482 size = 1; 483 sign = '\0'; 484 break; 485 case 'D': 486 flags |= LONGINT; 487 /*FALLTHROUGH*/ 488 case 'd': 489 case 'i': 490 _uintmax = SARG(); 491 if ((intmax_t)_uintmax < 0) { 492 _uintmax = -_uintmax; 493 sign = '-'; 494 } 495 base = DEC; 496 goto number; 497 #ifndef NO_FLOATING_POINT 498 case 'e': 499 case 'E': 500 case 'f': 501 case 'F': 502 case 'g': 503 case 'G': 504 if (prec == -1) { 505 prec = DEFPREC; 506 } else if ((ch == 'g' || ch == 'G') && prec == 0) { 507 prec = 1; 508 } 509 510 if (flags & LONGDBL) { 511 _double = (double) va_arg(ap, long double); 512 } else { 513 _double = va_arg(ap, double); 514 } 515 516 /* do this before tricky precision changes */ 517 if (isinf(_double)) { 518 if (_double < 0) 519 sign = '-'; 520 if (ch == 'E' || ch == 'F' || ch == 'G') 521 cp = "INF"; 522 else 523 cp = "inf"; 524 size = 3; 525 break; 526 } 527 if (isnan(_double)) { 528 if (ch == 'E' || ch == 'F' || ch == 'G') 529 cp = "NAN"; 530 else 531 cp = "nan"; 532 size = 3; 533 break; 534 } 535 if (fp->_flags & __SAFE) { 536 if (ch == 'E' || ch == 'F' || ch == 'G') 537 cp = "UNK"; 538 else 539 cp = "unk"; 540 size = 3; 541 break; 542 } 543 544 flags |= FPT; 545 if (dtoaresult) 546 __freedtoa(dtoaresult); 547 cp = dtoaresult = cvt(_double, prec, flags, &softsign, 548 &expt, ch, &ndig); 549 if (ch == 'g' || ch == 'G') { 550 if (expt <= -4 || expt > prec) 551 ch = (ch == 'g') ? 'e' : 'E'; 552 else 553 ch = 'g'; 554 } 555 if (ch == 'e' || ch == 'E') { 556 --expt; 557 expsize = exponent(expstr, expt, ch); 558 size = expsize + ndig; 559 if (ndig > 1 || flags & ALT) 560 ++size; 561 } else if (ch == 'f' || ch == 'F') { 562 if (expt > 0) { 563 size = expt; 564 if (prec || flags & ALT) 565 size += prec + 1; 566 } else /* "0.X" */ 567 size = prec + 2; 568 } else if (expt >= ndig) { /* fixed g fmt */ 569 size = expt; 570 if (flags & ALT) 571 ++size; 572 } else 573 size = ndig + (expt > 0 ? 574 1 : 2 - expt); 575 576 if (softsign) 577 sign = '-'; 578 break; 579 #endif /* NO_FLOATING_POINT */ 580 case 'n': 581 if (flags & MAXINT) 582 *va_arg(ap, intmax_t *) = ret; 583 else if (flags & PTRINT) 584 *va_arg(ap, ptrdiff_t *) = ret; 585 else if (flags & SIZEINT) 586 *va_arg(ap, ssize_t *) = ret; /* XXX */ 587 else if (flags & QUADINT) 588 *va_arg(ap, quad_t *) = ret; 589 else if (flags & LONGINT) 590 *va_arg(ap, long *) = ret; 591 else if (flags & SHORTINT) 592 *va_arg(ap, short *) = ret; 593 else 594 *va_arg(ap, int *) = ret; 595 continue; /* no output */ 596 case 'O': 597 flags |= LONGINT; 598 /*FALLTHROUGH*/ 599 case 'o': 600 _uintmax = UARG(); 601 base = OCT; 602 goto nosign; 603 case 'p': 604 /* 605 * ``The argument shall be a pointer to void. The 606 * value of the pointer is converted to a sequence 607 * of printable characters, in an implementation- 608 * defined manner.'' 609 * -- ANSI X3J11 610 */ 611 /* NOSTRICT */ 612 _uintmax = (u_long)va_arg(ap, void *); 613 base = HEX; 614 xdigs = "0123456789abcdef"; 615 flags |= HEXPREFIX; 616 ch = 'x'; 617 goto nosign; 618 case 's': 619 if ((cp = va_arg(ap, char *)) == NULL) 620 cp = "(null)"; 621 if (prec >= 0) { 622 /* 623 * can't use strlen; can only look for the 624 * NUL in the first `prec' characters, and 625 * strlen() will go further. 626 */ 627 for (n = 0; n < prec && cp[n]; n++) 628 continue; 629 size = n; 630 } else { 631 size_t len = strlen(cp); 632 633 if (len > INT_MAX) 634 goto overflow; 635 size = len; 636 } 637 sign = '\0'; 638 break; 639 case 'U': 640 flags |= LONGINT; 641 /*FALLTHROUGH*/ 642 case 'u': 643 _uintmax = UARG(); 644 base = DEC; 645 goto nosign; 646 case 'X': 647 xdigs = "0123456789ABCDEF"; 648 goto hex; 649 case 'x': 650 xdigs = "0123456789abcdef"; 651 hex: _uintmax = UARG(); 652 base = HEX; 653 /* leading 0x/X only if non-zero */ 654 if (flags & ALT && _uintmax != 0) 655 flags |= HEXPREFIX; 656 657 /* unsigned conversions */ 658 nosign: sign = '\0'; 659 /* 660 * ``... diouXx conversions ... if a precision is 661 * specified, the 0 flag will be ignored.'' 662 * -- ANSI X3J11 663 */ 664 number: if ((dprec = prec) >= 0) 665 flags &= ~ZEROPAD; 666 667 /* 668 * ``The result of converting a zero value with an 669 * explicit precision of zero is no characters.'' 670 * -- ANSI X3J11 671 */ 672 bp = buf + BUF; 673 if (_uintmax != 0 || prec != 0) { 674 /* 675 * Unsigned mod is hard, and unsigned mod 676 * by a constant is easier than that by 677 * a variable; hence this switch. 678 */ 679 switch (base) { 680 case OCT: 681 do { 682 *--bp = to_char(_uintmax & 7); 683 _uintmax >>= 3; 684 } while (_uintmax); 685 /* handle octal leading 0 */ 686 if (flags & ALT && *bp != '0') 687 *--bp = '0'; 688 break; 689 690 case DEC: 691 /* many numbers are 1 digit */ 692 while (_uintmax >= 10) { 693 *--bp = to_char(_uintmax % 10); 694 _uintmax /= 10; 695 } 696 *--bp = to_char(_uintmax); 697 break; 698 699 case HEX: 700 do { 701 *--bp = xdigs[(size_t) 702 (_uintmax & 15)]; 703 _uintmax >>= 4; 704 } while (_uintmax); 705 break; 706 707 default: 708 cp = "bug in vfprintf: bad base"; 709 size = strlen(cp); 710 goto skipsize; 711 } 712 } 713 cp = bp; 714 size = buf + BUF - bp; 715 skipsize: 716 break; 717 default: /* "%?" prints ?, unless ? is NUL */ 718 if (ch == '\0') 719 goto done; 720 /* pretend it was %c with argument ch */ 721 *buf = ch; 722 cp = buf; 723 size = 1; 724 sign = '\0'; 725 break; 726 } 727 728 /* 729 * All reasonable formats wind up here. At this point, `cp' 730 * points to a string which (if not flags&LADJUST) should be 731 * padded out to `width' places. If flags&ZEROPAD, it should 732 * first be prefixed by any sign or other prefix; otherwise, 733 * it should be blank padded before the prefix is emitted. 734 * After any left-hand padding and prefixing, emit zeroes 735 * required by a decimal [diouxX] precision, then print the 736 * string proper, then emit zeroes required by any leftover 737 * floating precision; finally, if LADJUST, pad with blanks. 738 * 739 * Compute actual size, so we know how much to pad. 740 * size excludes decimal prec; realsz includes it. 741 */ 742 realsz = dprec > size ? dprec : size; 743 if (sign) 744 realsz++; 745 else if (flags & HEXPREFIX) 746 realsz+= 2; 747 748 /* right-adjusting blank padding */ 749 if ((flags & (LADJUST|ZEROPAD)) == 0) 750 PAD(width - realsz, blanks); 751 752 /* prefix */ 753 if (sign) { 754 PRINT(&sign, 1); 755 } else if (flags & HEXPREFIX) { 756 ox[0] = '0'; 757 ox[1] = ch; 758 PRINT(ox, 2); 759 } 760 761 /* right-adjusting zero padding */ 762 if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) 763 PAD(width - realsz, zeroes); 764 765 /* leading zeroes from decimal precision */ 766 PAD(dprec - size, zeroes); 767 768 /* the string or number proper */ 769 #ifndef NO_FLOATING_POINT 770 if ((flags & FPT) == 0) { 771 PRINT(cp, size); 772 } else { /* glue together f_p fragments */ 773 if (ch >= 'f') { /* 'f' or 'g' */ 774 if (decimal_point == NULL) 775 decimal_point = 776 localeconv()->decimal_point; 777 if (_double == 0) { 778 /* kludge for __dtoa irregularity */ 779 PRINT("0", 1); 780 if (expt < ndig || (flags & ALT) != 0) { 781 PRINT(decimal_point, 1); 782 PAD(ndig - 1, zeroes); 783 } 784 } else if (expt <= 0) { 785 PRINT("0", 1); 786 PRINT(decimal_point, 1); 787 PAD(-expt, zeroes); 788 PRINT(cp, ndig); 789 } else if (expt >= ndig) { 790 PRINT(cp, ndig); 791 PAD(expt - ndig, zeroes); 792 if (flags & ALT) 793 PRINT(".", 1); 794 } else { 795 PRINT(cp, expt); 796 cp += expt; 797 PRINT(".", 1); 798 PRINT(cp, ndig-expt); 799 } 800 } else { /* 'e' or 'E' */ 801 if (ndig > 1 || flags & ALT) { 802 ox[0] = *cp++; 803 ox[1] = '.'; 804 PRINT(ox, 2); 805 if (_double) { 806 PRINT(cp, ndig-1); 807 } else /* 0.[0..] */ 808 /* __dtoa irregularity */ 809 PAD(ndig - 1, zeroes); 810 } else /* XeYYY */ 811 PRINT(cp, 1); 812 PRINT(expstr, expsize); 813 } 814 } 815 #else 816 PRINT(cp, size); 817 #endif 818 /* left-adjusting padding (always blank) */ 819 if (flags & LADJUST) 820 PAD(width - realsz, blanks); 821 822 /* finally, adjust ret */ 823 n = width > realsz ? width : realsz; 824 if (n > INT_MAX - ret) 825 goto overflow; 826 ret += n; 827 828 FLUSH(); /* copy out the I/O vectors */ 829 } 830 done: 831 FLUSH(); 832 error: 833 if (__sferror(fp)) 834 ret = -1; 835 goto finish; 836 837 overflow: 838 errno = EOVERFLOW; 839 ret = -1; 840 841 finish: 842 #ifndef NO_FLOATING_POINT 843 if (dtoaresult) 844 __freedtoa(dtoaresult); 845 #endif 846 return (ret); 847 } 848 849 #ifndef NO_FLOATING_POINT 850 851 static char * 852 cvt(value, ndigits, flags, sign, decpt, ch, length) 853 double value; 854 int ndigits, flags, *decpt, ch, *length; 855 char *sign; 856 { 857 int mode, dsgn; 858 char *digits, *bp, *rve; 859 860 _DIAGASSERT(decpt != NULL); 861 _DIAGASSERT(length != NULL); 862 _DIAGASSERT(sign != NULL); 863 864 if (ch == 'f') { 865 mode = 3; /* ndigits after the decimal point */ 866 } else { 867 /* To obtain ndigits after the decimal point for the 'e' 868 * and 'E' formats, round to ndigits + 1 significant 869 * figures. 870 */ 871 if (ch == 'e' || ch == 'E') { 872 ndigits++; 873 } 874 mode = 2; /* ndigits significant digits */ 875 } 876 877 digits = __dtoa(value, mode, ndigits, decpt, &dsgn, &rve); 878 if (dsgn) { 879 value = -value; 880 *sign = '-'; 881 } else 882 *sign = '\000'; 883 if ((ch != 'g' && ch != 'G') || flags & ALT) { /* Print trailing zeros */ 884 bp = digits + ndigits; 885 if (ch == 'f') { 886 if (*digits == '0' && value) 887 *decpt = -ndigits + 1; 888 bp += *decpt; 889 } 890 if (value == 0) /* kludge for __dtoa irregularity */ 891 rve = bp; 892 while (rve < bp) 893 *rve++ = '0'; 894 } 895 *length = rve - digits; 896 return (digits); 897 } 898 899 static int 900 exponent(p0, expon, fmtch) 901 char *p0; 902 int expon, fmtch; 903 { 904 char *p, *t; 905 char expbuf[MAXEXP]; 906 907 _DIAGASSERT(p0 != NULL); 908 909 p = p0; 910 *p++ = fmtch; 911 if (expon < 0) { 912 expon = -expon; 913 *p++ = '-'; 914 } 915 else 916 *p++ = '+'; 917 t = expbuf + MAXEXP; 918 if (expon > 9) { 919 do { 920 *--t = to_char(expon % 10); 921 } while ((expon /= 10) > 9); 922 *--t = to_char(expon); 923 for (; t < expbuf + MAXEXP; *p++ = *t++); 924 } 925 else { 926 *p++ = '0'; 927 *p++ = to_char(expon); 928 } 929 return (p - p0); 930 } 931 #endif /* NO_FLOATING_POINT */ 932
Indexes created Tue Sep 30 11:09:46 GMT 2025