1 /* $NetBSD: vfprintf.c,v 1.51 2006/10/27 19:59:58 christos 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 1.51 2006/10/27 19:59:58 christos 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 63 #include "reentrant.h" 64 #include "local.h" 65 #include "fvwrite.h" 66 #include "extern.h" 67 68 static int __sprint __P((FILE *, struct __suio *)); 69 static int __sbprintf __P((FILE *, const char *, va_list)) 70 __attribute__((__format__(__printf__, 2, 0))); 71 72 /* 73 * Flush out all the vectors defined by the given uio, 74 * then reset it so that it can be reused. 75 */ 76 /* NB: async-signal-safe when fp->_flags & __SAFE */ 77 static int 78 __sprint(fp, uio) 79 FILE *fp; 80 struct __suio *uio; 81 { 82 int err; 83 84 _DIAGASSERT(fp != NULL); 85 _DIAGASSERT(uio != NULL); 86 87 if (uio->uio_resid == 0) { 88 uio->uio_iovcnt = 0; 89 return (0); 90 } 91 err = __sfvwrite(fp, uio); 92 uio->uio_resid = 0; 93 uio->uio_iovcnt = 0; 94 return (err); 95 } 96 97 /* 98 * Helper function for `fprintf to unbuffered unix file': creates a 99 * temporary buffer. We only work on write-only files; this avoids 100 * worries about ungetc buffers and so forth. 101 */ 102 static int 103 __sbprintf(fp, fmt, ap) 104 FILE *fp; 105 const char *fmt; 106 va_list ap; 107 { 108 int ret; 109 FILE fake; 110 struct __sfileext fakeext; 111 unsigned char buf[BUFSIZ]; 112 113 _DIAGASSERT(fp != NULL); 114 _DIAGASSERT(fmt != NULL); 115 116 _FILEEXT_SETUP(&fake, &fakeext); 117 118 /* copy the important variables */ 119 fake._flags = fp->_flags & ~__SNBF; 120 fake._file = fp->_file; 121 fake._cookie = fp->_cookie; 122 fake._write = fp->_write; 123 124 /* set up the buffer */ 125 fake._bf._base = fake._p = buf; 126 fake._bf._size = fake._w = sizeof(buf); 127 fake._lbfsize = 0; /* not actually used, but Just In Case */ 128 129 /* do the work, then copy any error status */ 130 ret = vfprintf(&fake, fmt, ap); 131 if (ret >= 0 && fflush(&fake)) 132 ret = -1; 133 if (fake._flags & __SERR) 134 fp->_flags |= __SERR; 135 return (ret); 136 } 137 138 139 #ifndef NO_FLOATING_POINT 140 #include <locale.h> 141 #include <math.h> 142 #include "floatio.h" 143 144 #define BUF (MAXEXP+MAXFRACT+1) /* + decimal point */ 145 #define DEFPREC 6 146 147 static char *cvt __P((double, int, int, char *, int *, int, int *)); 148 static int exponent __P((char *, int, int)); 149 150 #else /* FLOATING_POINT */ 151 152 #define BUF 40 153 154 #endif /* NO_FLOATING_POINT */ 155 156 /* 157 * Macros for converting digits to letters and vice versa 158 */ 159 #define to_digit(c) ((c) - '0') 160 #define is_digit(c) ((unsigned)to_digit(c) <= 9) 161 #define to_char(n) ((char)((n) + '0')) 162 163 /* 164 * Flags used during conversion. 165 */ 166 #define ALT 0x001 /* alternate form */ 167 #define HEXPREFIX 0x002 /* add 0x or 0X prefix */ 168 #define LADJUST 0x004 /* left adjustment */ 169 #define LONGDBL 0x008 /* long double; unimplemented */ 170 #define LONGINT 0x010 /* long integer */ 171 #define QUADINT 0x020 /* quad integer */ 172 #define SHORTINT 0x040 /* short integer */ 173 #define MAXINT 0x080 /* (unsigned) intmax_t */ 174 #define PTRINT 0x100 /* (unsigned) ptrdiff_t */ 175 #define SIZEINT 0x200 /* (signed) size_t */ 176 #define ZEROPAD 0x400 /* zero (as opposed to blank) pad */ 177 #define FPT 0x800 /* Floating point number */ 178 179 int 180 vfprintf(fp, fmt0, ap) 181 FILE *fp; 182 const char *fmt0; 183 _BSD_VA_LIST_ ap; 184 { 185 int ret; 186 187 FLOCKFILE(fp); 188 ret = __vfprintf_unlocked(fp, fmt0, ap); 189 FUNLOCKFILE(fp); 190 191 return ret; 192 } 193 194 195 196 /* NB: async-signal-safe when fp->_flags & __SAFE */ 197 int 198 __vfprintf_unlocked(fp, fmt0, ap) 199 FILE *fp; 200 const char *fmt0; 201 _BSD_VA_LIST_ ap; 202 { 203 const char *fmt;/* format string */ 204 int ch; /* character from fmt */ 205 int n, m; /* handy integers (short term usage) */ 206 const char *cp; /* handy char pointer (short term usage) */ 207 char *bp; /* handy char pointer (short term usage) */ 208 struct __siov *iovp;/* for PRINT macro */ 209 int flags; /* flags as above */ 210 int ret; /* return value accumulator */ 211 int width; /* width from format (%8d), or 0 */ 212 int prec; /* precision from format (%.3d), or -1 */ 213 char sign; /* sign prefix (' ', '+', '-', or \0) */ 214 wchar_t wc; 215 mbstate_t ps; 216 #ifndef NO_FLOATING_POINT 217 char *decimal_point = localeconv()->decimal_point; 218 char softsign; /* temporary negative sign for floats */ 219 double _double; /* double precision arguments %[eEfgG] */ 220 int expt; /* integer value of exponent */ 221 int expsize = 0; /* character count for expstr */ 222 int ndig; /* actual number of digits returned by cvt */ 223 char expstr[7]; /* buffer for exponent string */ 224 char *dtoaresult = NULL; 225 #endif 226 227 #ifdef __GNUC__ /* gcc has builtin quad type (long long) SOS */ 228 #define quad_t long long 229 #define u_quad_t unsigned long long 230 #endif 231 232 #define INTMAX_T intmax_t 233 #define UINTMAX_T uintmax_t 234 235 UINTMAX_T _uintmax; /* integer arguments %[diouxX] */ 236 enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */ 237 int dprec; /* a copy of prec if [diouxX], 0 otherwise */ 238 int realsz; /* field size expanded by dprec */ 239 int size; /* size of converted field or string */ 240 const char *xdigs = NULL;/* digits for [xX] conversion */ 241 #define NIOV 8 242 struct __suio uio; /* output information: summary */ 243 struct __siov iov[NIOV];/* ... and individual io vectors */ 244 char buf[BUF]; /* space for %c, %[diouxX], %[eEfgG] */ 245 char ox[2]; /* space for 0x hex-prefix */ 246 247 /* 248 * Choose PADSIZE to trade efficiency vs. size. If larger printf 249 * fields occur frequently, increase PADSIZE and make the initialisers 250 * below longer. 251 */ 252 #define PADSIZE 16 /* pad chunk size */ 253 static const char blanks[PADSIZE] = 254 {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '}; 255 static const char zeroes[PADSIZE] = 256 {'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'}; 257 258 /* 259 * BEWARE, these `goto error' on error, and PAD uses `n'. 260 */ 261 #define PRINT(ptr, len) { \ 262 iovp->iov_base = __UNCONST(ptr); \ 263 iovp->iov_len = (len); \ 264 uio.uio_resid += (len); \ 265 iovp++; \ 266 if (++uio.uio_iovcnt >= NIOV) { \ 267 if (__sprint(fp, &uio)) \ 268 goto error; \ 269 iovp = iov; \ 270 } \ 271 } 272 #define PAD(howmany, with) { \ 273 if ((n = (howmany)) > 0) { \ 274 while (n > PADSIZE) { \ 275 PRINT(with, PADSIZE); \ 276 n -= PADSIZE; \ 277 } \ 278 PRINT(with, n); \ 279 } \ 280 } 281 #define FLUSH() { \ 282 if (uio.uio_resid && __sprint(fp, &uio)) \ 283 goto error; \ 284 uio.uio_iovcnt = 0; \ 285 iovp = iov; \ 286 } 287 288 /* 289 * To extend shorts properly, we need both signed and unsigned 290 * argument extraction methods. 291 */ 292 #define SARG() \ 293 (flags&MAXINT ? va_arg(ap, intmax_t) : \ 294 flags&PTRINT ? va_arg(ap, ptrdiff_t) : \ 295 flags&SIZEINT ? va_arg(ap, ssize_t) : /* XXX */ \ 296 flags&QUADINT ? va_arg(ap, quad_t) : \ 297 flags&LONGINT ? va_arg(ap, long) : \ 298 flags&SHORTINT ? (long)(short)va_arg(ap, int) : \ 299 (long)va_arg(ap, int)) 300 #define UARG() \ 301 (flags&MAXINT ? va_arg(ap, uintmax_t) : \ 302 flags&PTRINT ? va_arg(ap, uintptr_t) : /* XXX */ \ 303 flags&SIZEINT ? va_arg(ap, size_t) : \ 304 flags&QUADINT ? va_arg(ap, u_quad_t) : \ 305 flags&LONGINT ? va_arg(ap, u_long) : \ 306 flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \ 307 (u_long)va_arg(ap, u_int)) 308 309 _DIAGASSERT(fp != NULL); 310 _DIAGASSERT(fmt0 != NULL); 311 312 _SET_ORIENTATION(fp, -1); 313 314 /* sorry, fprintf(read_only_file, "") returns -1, not 0 */ 315 if (cantwrite(fp)) { 316 errno = EBADF; 317 return (-1); 318 } 319 320 /* optimise fprintf(stderr) (and other unbuffered Unix files) */ 321 if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) && 322 fp->_file >= 0) { 323 ret = __sbprintf(fp, fmt0, ap); 324 return (ret); 325 } 326 327 fmt = fmt0; 328 uio.uio_iov = iovp = iov; 329 uio.uio_resid = 0; 330 uio.uio_iovcnt = 0; 331 ret = 0; 332 333 memset(&ps, 0, sizeof(ps)); 334 335 /* 336 * Scan the format for conversions (`%' character). 337 */ 338 for (;;) { 339 cp = fmt; 340 if (fp->_flags & __SAFE) { 341 for (; *fmt &&*fmt != '%'; fmt++) 342 continue; 343 } else { 344 while ((n = mbrtowc(&wc, fmt, MB_CUR_MAX, &ps)) > 0) { 345 fmt += n; 346 if (wc == '%') { 347 fmt--; 348 break; 349 } 350 } 351 } 352 if ((m = fmt - cp) != 0) { 353 PRINT(cp, m); 354 ret += m; 355 } 356 if (n <= 0) 357 goto done; 358 fmt++; /* skip over '%' */ 359 360 flags = 0; 361 dprec = 0; 362 width = 0; 363 prec = -1; 364 sign = '\0'; 365 366 rflag: ch = *fmt++; 367 reswitch: switch (ch) { 368 case ' ': 369 /* 370 * ``If the space and + flags both appear, the space 371 * flag will be ignored.'' 372 * -- ANSI X3J11 373 */ 374 if (!sign) 375 sign = ' '; 376 goto rflag; 377 case '#': 378 flags |= ALT; 379 goto rflag; 380 case '*': 381 /* 382 * ``A negative field width argument is taken as a 383 * - flag followed by a positive field width.'' 384 * -- ANSI X3J11 385 * They don't exclude field widths read from args. 386 */ 387 if ((width = va_arg(ap, int)) >= 0) 388 goto rflag; 389 width = -width; 390 /* FALLTHROUGH */ 391 case '-': 392 flags |= LADJUST; 393 goto rflag; 394 case '+': 395 sign = '+'; 396 goto rflag; 397 case '.': 398 if ((ch = *fmt++) == '*') { 399 n = va_arg(ap, int); 400 prec = n < 0 ? -1 : n; 401 goto rflag; 402 } 403 n = 0; 404 while (is_digit(ch)) { 405 n = 10 * n + to_digit(ch); 406 ch = *fmt++; 407 } 408 prec = n < 0 ? -1 : n; 409 goto reswitch; 410 case '0': 411 /* 412 * ``Note that 0 is taken as a flag, not as the 413 * beginning of a field width.'' 414 * -- ANSI X3J11 415 */ 416 flags |= ZEROPAD; 417 goto rflag; 418 case '1': case '2': case '3': case '4': 419 case '5': case '6': case '7': case '8': case '9': 420 n = 0; 421 do { 422 n = 10 * n + to_digit(ch); 423 ch = *fmt++; 424 } while (is_digit(ch)); 425 width = n; 426 goto reswitch; 427 #ifndef NO_FLOATING_POINT 428 case 'L': 429 flags |= LONGDBL; 430 goto rflag; 431 #endif 432 case 'h': 433 flags |= SHORTINT; 434 goto rflag; 435 case 'j': 436 flags |= MAXINT; 437 goto rflag; 438 case 'l': 439 if (*fmt == 'l') { 440 fmt++; 441 flags |= QUADINT; 442 } else { 443 flags |= LONGINT; 444 } 445 goto rflag; 446 case 'q': 447 flags |= QUADINT; 448 goto rflag; 449 case 't': 450 flags |= PTRINT; 451 goto rflag; 452 case 'z': 453 flags |= SIZEINT; 454 goto rflag; 455 case 'c': 456 *buf = va_arg(ap, int); 457 cp = buf; 458 size = 1; 459 sign = '\0'; 460 break; 461 case 'D': 462 flags |= LONGINT; 463 /*FALLTHROUGH*/ 464 case 'd': 465 case 'i': 466 _uintmax = SARG(); 467 if ((intmax_t)_uintmax < 0) { 468 _uintmax = -_uintmax; 469 sign = '-'; 470 } 471 base = DEC; 472 goto number; 473 #ifndef NO_FLOATING_POINT 474 case 'e': 475 case 'E': 476 case 'f': 477 case 'F': 478 case 'g': 479 case 'G': 480 if (prec == -1) { 481 prec = DEFPREC; 482 } else if ((ch == 'g' || ch == 'G') && prec == 0) { 483 prec = 1; 484 } 485 486 if (flags & LONGDBL) { 487 _double = (double) va_arg(ap, long double); 488 } else { 489 _double = va_arg(ap, double); 490 } 491 492 /* do this before tricky precision changes */ 493 if (isinf(_double)) { 494 if (_double < 0) 495 sign = '-'; 496 if (ch == 'E' || ch == 'F' || ch == 'G') 497 cp = "INF"; 498 else 499 cp = "inf"; 500 size = 3; 501 break; 502 } 503 if (isnan(_double)) { 504 if (ch == 'E' || ch == 'F' || ch == 'G') 505 cp = "NAN"; 506 else 507 cp = "nan"; 508 size = 3; 509 break; 510 } 511 if (fp->_flags & __SAFE) { 512 if (ch == 'E' || ch == 'F' || ch == 'G') 513 cp = "UNK"; 514 else 515 cp = "unk"; 516 size = 3; 517 break; 518 } 519 520 flags |= FPT; 521 if (dtoaresult) 522 __freedtoa(dtoaresult); 523 cp = dtoaresult = cvt(_double, prec, flags, &softsign, 524 &expt, ch, &ndig); 525 if (ch == 'g' || ch == 'G') { 526 if (expt <= -4 || expt > prec) 527 ch = (ch == 'g') ? 'e' : 'E'; 528 else 529 ch = 'g'; 530 } 531 if (ch == 'e' || ch == 'E') { 532 --expt; 533 expsize = exponent(expstr, expt, ch); 534 size = expsize + ndig; 535 if (ndig > 1 || flags & ALT) 536 ++size; 537 } else if (ch == 'f' || ch == 'F') { 538 if (expt > 0) { 539 size = expt; 540 if (prec || flags & ALT) 541 size += prec + 1; 542 } else /* "0.X" */ 543 size = prec + 2; 544 } else if (expt >= ndig) { /* fixed g fmt */ 545 size = expt; 546 if (flags & ALT) 547 ++size; 548 } else 549 size = ndig + (expt > 0 ? 550 1 : 2 - expt); 551 552 if (softsign) 553 sign = '-'; 554 break; 555 #endif /* NO_FLOATING_POINT */ 556 case 'n': 557 if (flags & MAXINT) 558 *va_arg(ap, intmax_t *) = ret; 559 else if (flags & PTRINT) 560 *va_arg(ap, ptrdiff_t *) = ret; 561 else if (flags & SIZEINT) 562 *va_arg(ap, ssize_t *) = ret; /* XXX */ 563 else if (flags & QUADINT) 564 *va_arg(ap, quad_t *) = ret; 565 else if (flags & LONGINT) 566 *va_arg(ap, long *) = ret; 567 else if (flags & SHORTINT) 568 *va_arg(ap, short *) = ret; 569 else 570 *va_arg(ap, int *) = ret; 571 continue; /* no output */ 572 case 'O': 573 flags |= LONGINT; 574 /*FALLTHROUGH*/ 575 case 'o': 576 _uintmax = UARG(); 577 base = OCT; 578 goto nosign; 579 case 'p': 580 /* 581 * ``The argument shall be a pointer to void. The 582 * value of the pointer is converted to a sequence 583 * of printable characters, in an implementation- 584 * defined manner.'' 585 * -- ANSI X3J11 586 */ 587 /* NOSTRICT */ 588 _uintmax = (u_long)va_arg(ap, void *); 589 base = HEX; 590 xdigs = "0123456789abcdef"; 591 flags |= HEXPREFIX; 592 ch = 'x'; 593 goto nosign; 594 case 's': 595 if ((cp = va_arg(ap, char *)) == NULL) 596 cp = "(null)"; 597 if (prec >= 0) { 598 /* 599 * can't use strlen; can only look for the 600 * NUL in the first `prec' characters, and 601 * strlen() will go further. 602 */ 603 char *p = memchr(cp, 0, (size_t)prec); 604 605 if (p != NULL) { 606 size = p - cp; 607 if (size > prec) 608 size = prec; 609 } else 610 size = prec; 611 } else 612 size = strlen(cp); 613 sign = '\0'; 614 break; 615 case 'U': 616 flags |= LONGINT; 617 /*FALLTHROUGH*/ 618 case 'u': 619 _uintmax = UARG(); 620 base = DEC; 621 goto nosign; 622 case 'X': 623 xdigs = "0123456789ABCDEF"; 624 goto hex; 625 case 'x': 626 xdigs = "0123456789abcdef"; 627 hex: _uintmax = UARG(); 628 base = HEX; 629 /* leading 0x/X only if non-zero */ 630 if (flags & ALT && _uintmax != 0) 631 flags |= HEXPREFIX; 632 633 /* unsigned conversions */ 634 nosign: sign = '\0'; 635 /* 636 * ``... diouXx conversions ... if a precision is 637 * specified, the 0 flag will be ignored.'' 638 * -- ANSI X3J11 639 */ 640 number: if ((dprec = prec) >= 0) 641 flags &= ~ZEROPAD; 642 643 /* 644 * ``The result of converting a zero value with an 645 * explicit precision of zero is no characters.'' 646 * -- ANSI X3J11 647 */ 648 bp = buf + BUF; 649 if (_uintmax != 0 || prec != 0) { 650 /* 651 * Unsigned mod is hard, and unsigned mod 652 * by a constant is easier than that by 653 * a variable; hence this switch. 654 */ 655 switch (base) { 656 case OCT: 657 do { 658 *--bp = to_char(_uintmax & 7); 659 _uintmax >>= 3; 660 } while (_uintmax); 661 /* handle octal leading 0 */ 662 if (flags & ALT && *bp != '0') 663 *--bp = '0'; 664 break; 665 666 case DEC: 667 /* many numbers are 1 digit */ 668 while (_uintmax >= 10) { 669 *--bp = to_char(_uintmax % 10); 670 _uintmax /= 10; 671 } 672 *--bp = to_char(_uintmax); 673 break; 674 675 case HEX: 676 do { 677 *--bp = xdigs[(size_t) 678 (_uintmax & 15)]; 679 _uintmax >>= 4; 680 } while (_uintmax); 681 break; 682 683 default: 684 cp = "bug in vfprintf: bad base"; 685 size = strlen(cp); 686 goto skipsize; 687 } 688 } 689 cp = bp; 690 size = buf + BUF - bp; 691 skipsize: 692 break; 693 default: /* "%?" prints ?, unless ? is NUL */ 694 if (ch == '\0') 695 goto done; 696 /* pretend it was %c with argument ch */ 697 *buf = ch; 698 cp = buf; 699 size = 1; 700 sign = '\0'; 701 break; 702 } 703 704 /* 705 * All reasonable formats wind up here. At this point, `cp' 706 * points to a string which (if not flags&LADJUST) should be 707 * padded out to `width' places. If flags&ZEROPAD, it should 708 * first be prefixed by any sign or other prefix; otherwise, 709 * it should be blank padded before the prefix is emitted. 710 * After any left-hand padding and prefixing, emit zeroes 711 * required by a decimal [diouxX] precision, then print the 712 * string proper, then emit zeroes required by any leftover 713 * floating precision; finally, if LADJUST, pad with blanks. 714 * 715 * Compute actual size, so we know how much to pad. 716 * size excludes decimal prec; realsz includes it. 717 */ 718 realsz = dprec > size ? dprec : size; 719 if (sign) 720 realsz++; 721 else if (flags & HEXPREFIX) 722 realsz+= 2; 723 724 /* right-adjusting blank padding */ 725 if ((flags & (LADJUST|ZEROPAD)) == 0) 726 PAD(width - realsz, blanks); 727 728 /* prefix */ 729 if (sign) { 730 PRINT(&sign, 1); 731 } else if (flags & HEXPREFIX) { 732 ox[0] = '0'; 733 ox[1] = ch; 734 PRINT(ox, 2); 735 } 736 737 /* right-adjusting zero padding */ 738 if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) 739 PAD(width - realsz, zeroes); 740 741 /* leading zeroes from decimal precision */ 742 PAD(dprec - size, zeroes); 743 744 /* the string or number proper */ 745 #ifndef NO_FLOATING_POINT 746 if ((flags & FPT) == 0) { 747 PRINT(cp, size); 748 } else { /* glue together f_p fragments */ 749 if (ch >= 'f') { /* 'f' or 'g' */ 750 if (_double == 0) { 751 /* kludge for __dtoa irregularity */ 752 PRINT("0", 1); 753 if (expt < ndig || (flags & ALT) != 0) { 754 PRINT(decimal_point, 1); 755 PAD(ndig - 1, zeroes); 756 } 757 } else if (expt <= 0) { 758 PRINT("0", 1); 759 PRINT(decimal_point, 1); 760 PAD(-expt, zeroes); 761 PRINT(cp, ndig); 762 } else if (expt >= ndig) { 763 PRINT(cp, ndig); 764 PAD(expt - ndig, zeroes); 765 if (flags & ALT) 766 PRINT(".", 1); 767 } else { 768 PRINT(cp, expt); 769 cp += expt; 770 PRINT(".", 1); 771 PRINT(cp, ndig-expt); 772 } 773 } else { /* 'e' or 'E' */ 774 if (ndig > 1 || flags & ALT) { 775 ox[0] = *cp++; 776 ox[1] = '.'; 777 PRINT(ox, 2); 778 if (_double) { 779 PRINT(cp, ndig-1); 780 } else /* 0.[0..] */ 781 /* __dtoa irregularity */ 782 PAD(ndig - 1, zeroes); 783 } else /* XeYYY */ 784 PRINT(cp, 1); 785 PRINT(expstr, expsize); 786 } 787 } 788 #else 789 PRINT(cp, size); 790 #endif 791 /* left-adjusting padding (always blank) */ 792 if (flags & LADJUST) 793 PAD(width - realsz, blanks); 794 795 /* finally, adjust ret */ 796 ret += width > realsz ? width : realsz; 797 798 FLUSH(); /* copy out the I/O vectors */ 799 } 800 done: 801 FLUSH(); 802 error: 803 #ifndef NO_FLOATING_POINT 804 if (dtoaresult) 805 __freedtoa(dtoaresult); 806 #endif 807 if (__sferror(fp)) 808 ret = -1; 809 return (ret); 810 } 811 812 #ifndef NO_FLOATING_POINT 813 814 static char * 815 cvt(value, ndigits, flags, sign, decpt, ch, length) 816 double value; 817 int ndigits, flags, *decpt, ch, *length; 818 char *sign; 819 { 820 int mode, dsgn; 821 char *digits, *bp, *rve; 822 823 _DIAGASSERT(decpt != NULL); 824 _DIAGASSERT(length != NULL); 825 _DIAGASSERT(sign != NULL); 826 827 if (ch == 'f') { 828 mode = 3; /* ndigits after the decimal point */ 829 } else { 830 /* To obtain ndigits after the decimal point for the 'e' 831 * and 'E' formats, round to ndigits + 1 significant 832 * figures. 833 */ 834 if (ch == 'e' || ch == 'E') { 835 ndigits++; 836 } 837 mode = 2; /* ndigits significant digits */ 838 } 839 840 digits = __dtoa(value, mode, ndigits, decpt, &dsgn, &rve); 841 if (dsgn) { 842 value = -value; 843 *sign = '-'; 844 } else 845 *sign = '\000'; 846 if ((ch != 'g' && ch != 'G') || flags & ALT) { /* Print trailing zeros */ 847 bp = digits + ndigits; 848 if (ch == 'f') { 849 if (*digits == '0' && value) 850 *decpt = -ndigits + 1; 851 bp += *decpt; 852 } 853 if (value == 0) /* kludge for __dtoa irregularity */ 854 rve = bp; 855 while (rve < bp) 856 *rve++ = '0'; 857 } 858 *length = rve - digits; 859 return (digits); 860 } 861 862 static int 863 exponent(p0, expon, fmtch) 864 char *p0; 865 int expon, fmtch; 866 { 867 char *p, *t; 868 char expbuf[MAXEXP]; 869 870 _DIAGASSERT(p0 != NULL); 871 872 p = p0; 873 *p++ = fmtch; 874 if (expon < 0) { 875 expon = -expon; 876 *p++ = '-'; 877 } 878 else 879 *p++ = '+'; 880 t = expbuf + MAXEXP; 881 if (expon > 9) { 882 do { 883 *--t = to_char(expon % 10); 884 } while ((expon /= 10) > 9); 885 *--t = to_char(expon); 886 for (; t < expbuf + MAXEXP; *p++ = *t++); 887 } 888 else { 889 *p++ = '0'; 890 *p++ = to_char(expon); 891 } 892 return (p - p0); 893 } 894 #endif /* NO_FLOATING_POINT */ 895