1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Chris Torek. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)vfprintf.c 8.1 (Berkeley) 6/4/93 37 * $FreeBSD: src/lib/libc/stdio/vfprintf.c,v 1.34 2001/12/13 19:45:41 phantom Exp $ 38 * $DragonFly: src/lib/libc/stdio/vfprintf.c,v 1.11 2005/07/23 23:14:44 joerg Exp $ 39 */ 40 41 /* 42 * Actual printf innards. 43 * 44 * This code is large and complicated... 45 */ 46 47 #include "namespace.h" 48 #include <sys/types.h> 49 50 #include <ctype.h> 51 #include <limits.h> 52 #include <locale.h> 53 #include <stddef.h> 54 #include <stdint.h> 55 #include <stdio.h> 56 #include <stdlib.h> 57 #include <string.h> 58 59 #include <stdarg.h> 60 #include "un-namespace.h" 61 62 #include "libc_private.h" 63 #include "local.h" 64 #include "priv_stdio.h" 65 66 /* Define FLOATING_POINT to get floating point. */ 67 #define FLOATING_POINT 68 69 /* Borrowed from sys/systm.h, which is _KERNEL-only: */ 70 #define CTASSERT(x) _CTASSERT(x, __LINE__) 71 #define _CTASSERT(x, y) __CTASSERT(x, y) 72 #define __CTASSERT(x, y) typedef char __assert ## y[(x) ? 1 : -1] 73 74 /* This code assumes that a quad_t can fit in a long long: */ 75 CTASSERT(sizeof(quad_t) == sizeof(long long)); 76 77 union arg { 78 int intarg; 79 unsigned int uintarg; 80 long longarg; 81 unsigned long ulongarg; 82 long long longlongarg; 83 unsigned long long ulonglongarg; 84 ptrdiff_t ptrdiffarg; 85 size_t sizearg; 86 intmax_t intmaxarg; 87 uintmax_t uintmaxarg; 88 void *pvoidarg; 89 char *pchararg; 90 signed char *pschararg; 91 short *pshortarg; 92 int *pintarg; 93 long *plongarg; 94 long long *plonglongarg; 95 ptrdiff_t *pptrdiffarg; 96 size_t *psizearg; 97 intmax_t *pintmaxarg; 98 #ifdef FLOATING_POINT 99 double doublearg; 100 long double longdoublearg; 101 #endif 102 }; 103 104 /* 105 * Type ids for argument type table. 106 */ 107 enum typeid { 108 T_UNUSED, TP_SHORT, T_INT, T_U_INT, TP_INT, 109 T_LONG, T_U_LONG, TP_LONG, T_LLONG, T_U_LLONG, TP_LLONG, 110 T_PTRDIFFT, TP_PTRDIFFT, T_SIZET, TP_SIZET, 111 T_INTMAXT, T_UINTMAXT, TP_INTMAXT, TP_VOID, TP_CHAR, TP_SCHAR, 112 T_DOUBLE, T_LONG_DOUBLE 113 }; 114 115 static int __sprint(FILE *, struct __suio *); 116 static int __sbprintf(FILE *, const char *, va_list) __printflike(2, 0); 117 static char * __ujtoa(uintmax_t, char *, int, int, char *, int, 118 char, const char *); 119 static char * __ultoa(u_long, char *, int, int, char *, int, 120 char, const char *); 121 static void __find_arguments(const char *, va_list, union arg **); 122 static void __grow_type_table(int, enum typeid **, int *); 123 124 /* 125 * Flush out all the vectors defined by the given uio, 126 * then reset it so that it can be reused. 127 */ 128 static int 129 __sprint(FILE *fp, struct __suio *uio) 130 { 131 int err; 132 133 if (uio->uio_resid == 0) { 134 uio->uio_iovcnt = 0; 135 return (0); 136 } 137 err = __sfvwrite(fp, uio); 138 uio->uio_resid = 0; 139 uio->uio_iovcnt = 0; 140 return (err); 141 } 142 143 /* 144 * Helper function for `fprintf to unbuffered unix file': creates a 145 * temporary buffer. We only work on write-only files; this avoids 146 * worries about ungetc buffers and so forth. 147 */ 148 static int 149 __sbprintf(FILE *fp, const char *fmt, va_list ap) 150 { 151 int ret; 152 FILE fake; 153 unsigned char buf[BUFSIZ]; 154 155 /* copy the important variables */ 156 fake.pub._flags = fp->pub._flags & ~__SNBF; 157 fake.pub._fileno = fp->pub._fileno; 158 fake._cookie = fp->_cookie; 159 fake._write = fp->_write; 160 161 fake._up = fp->_up; 162 fake.fl_mutex = fp->fl_mutex; 163 fake.fl_owner = fp->fl_owner; 164 fake.fl_count = fp->fl_count; 165 166 /* set up the buffer */ 167 fake._bf._base = fake.pub._p = buf; 168 fake._bf._size = fake.pub._w = sizeof(buf); 169 fake.pub._lbfsize = 0; /* not actually used, but Just In Case */ 170 171 /* do the work, then copy any error status */ 172 ret = __vfprintf(&fake, fmt, ap); 173 if (ret >= 0 && __fflush(&fake)) 174 ret = EOF; 175 if (fake.pub._flags & __SERR) 176 fp->pub._flags |= __SERR; 177 return (ret); 178 } 179 180 /* 181 * Macros for converting digits to letters and vice versa 182 */ 183 #define to_digit(c) ((c) - '0') 184 #define is_digit(c) ((unsigned)to_digit(c) <= 9) 185 #define to_char(n) ((n) + '0') 186 187 /* 188 * Convert an unsigned long to ASCII for printf purposes, returning 189 * a pointer to the first character of the string representation. 190 * Octal numbers can be forced to have a leading zero; hex numbers 191 * use the given digits. 192 */ 193 static char * 194 __ultoa(u_long val, char *endp, int base, int octzero, char *xdigs, 195 int needgrp, char thousep, const char *grp) 196 { 197 char *cp = endp; 198 long sval; 199 int ndig; 200 201 /* 202 * Handle the three cases separately, in the hope of getting 203 * better/faster code. 204 */ 205 switch (base) { 206 case 10: 207 if (val < 10) { /* many numbers are 1 digit */ 208 *--cp = to_char(val); 209 return (cp); 210 } 211 ndig = 0; 212 /* 213 * On many machines, unsigned arithmetic is harder than 214 * signed arithmetic, so we do at most one unsigned mod and 215 * divide; this is sufficient to reduce the range of 216 * the incoming value to where signed arithmetic works. 217 */ 218 if (val > LONG_MAX) { 219 *--cp = to_char(val % 10); 220 ndig++; 221 sval = val / 10; 222 } else 223 sval = val; 224 do { 225 *--cp = to_char(sval % 10); 226 ndig++; 227 /* 228 * If (*grp == CHAR_MAX) then no more grouping 229 * should be performed. 230 */ 231 if (needgrp && ndig == *grp && *grp != CHAR_MAX && 232 sval > 9) { 233 *--cp = thousep; 234 ndig = 0; 235 /* 236 * If (*(grp+1) == '\0') then we have to 237 * use *grp character (last grouping rule) 238 * for all next cases 239 */ 240 if (*(grp + 1) != '\0') 241 grp++; 242 } 243 sval /= 10; 244 } while (sval != 0); 245 break; 246 247 case 8: 248 do { 249 *--cp = to_char(val & 7); 250 val >>= 3; 251 } while (val); 252 if (octzero && *cp != '0') 253 *--cp = '0'; 254 break; 255 256 case 16: 257 do { 258 *--cp = xdigs[val & 15]; 259 val >>= 4; 260 } while (val); 261 break; 262 263 default: /* oops */ 264 abort(); 265 } 266 return (cp); 267 } 268 269 /* Identical to __ultoa, but for intmax_t. */ 270 static char * 271 __ujtoa(u_quad_t val, char *endp, int base, int octzero, char *xdigs, 272 int needgrp, char thousep, const char *grp) 273 { 274 char *cp = endp; 275 intmax_t sval; 276 int ndig; 277 278 /* quick test for small values; __ultoa is typically much faster */ 279 /* (perhaps instead we should run until small, then call __ultoa?) */ 280 if (val <= ULONG_MAX) 281 return (__ultoa((u_long)val, endp, base, octzero, xdigs, 282 needgrp, thousep, grp)); 283 switch (base) { 284 case 10: 285 if (val < 10) { 286 *--cp = to_char(val % 10); 287 return (cp); 288 } 289 ndig = 0; 290 if (val > INTMAX_MAX) { 291 *--cp = to_char(val % 10); 292 ndig++; 293 sval = val / 10; 294 } else 295 sval = val; 296 do { 297 *--cp = to_char(sval % 10); 298 ndig++; 299 /* 300 * If (*grp == CHAR_MAX) then no more grouping 301 * should be performed. 302 */ 303 if (needgrp && *grp != CHAR_MAX && ndig == *grp && 304 sval > 9) { 305 *--cp = thousep; 306 ndig = 0; 307 /* 308 * If (*(grp+1) == '\0') then we have to 309 * use *grp character (last grouping rule) 310 * for all next cases 311 */ 312 if (*(grp + 1) != '\0') 313 grp++; 314 } 315 sval /= 10; 316 } while (sval != 0); 317 break; 318 319 case 8: 320 do { 321 *--cp = to_char(val & 7); 322 val >>= 3; 323 } while (val); 324 if (octzero && *cp != '0') 325 *--cp = '0'; 326 break; 327 328 case 16: 329 do { 330 *--cp = xdigs[val & 15]; 331 val >>= 4; 332 } while (val); 333 break; 334 335 default: 336 abort(); 337 } 338 return (cp); 339 } 340 341 /* 342 * MT-safe version 343 */ 344 int 345 vfprintf(FILE *fp, const char *fmt0, va_list ap) 346 { 347 int ret; 348 349 FLOCKFILE(fp); 350 ret = __vfprintf(fp, fmt0, ap); 351 FUNLOCKFILE(fp); 352 return (ret); 353 } 354 355 #ifdef FLOATING_POINT 356 #include <math.h> 357 #include "floatio.h" 358 359 #define BUF ((MAXEXP * 2) + MAXFRACT + 1) /* + decimal point */ 360 #define DEFPREC 6 361 362 static char *cvt (double, int, int, char *, int *, int, int *, char **); 363 static int exponent (char *, int, int); 364 365 #else /* no FLOATING_POINT */ 366 367 #define BUF 136 368 369 #endif /* FLOATING_POINT */ 370 371 #define STATIC_ARG_TBL_SIZE 8 /* Size of static argument table. */ 372 373 /* 374 * Flags used during conversion. 375 */ 376 #define ALT 0x001 /* alternate form */ 377 #define HEXPREFIX 0x002 /* add 0x or 0X prefix */ 378 #define LADJUST 0x004 /* left adjustment */ 379 #define LONGDBL 0x008 /* long double */ 380 #define LONGINT 0x010 /* long integer */ 381 #define LLONGINT 0x020 /* long long integer */ 382 #define SHORTINT 0x040 /* short integer */ 383 #define ZEROPAD 0x080 /* zero (as opposed to blank) pad */ 384 #define FPT 0x100 /* Floating point number */ 385 #define GROUPING 0x200 /* use grouping ("'" flag) */ 386 /* C99 additional size modifiers: */ 387 #define SIZET 0x400 /* size_t */ 388 #define PTRDIFFT 0x800 /* ptrdiff_t */ 389 #define INTMAXT 0x1000 /* intmax_t */ 390 #define CHARINT 0x2000 /* print char using int format */ 391 /* 392 * Non-MT-safe version 393 */ 394 int 395 __vfprintf(FILE *fp, const char *fmt0, va_list ap) 396 { 397 char *fmt; /* format string */ 398 int ch; /* character from fmt */ 399 int n, n2; /* handy integer (short term usage) */ 400 char *cp; /* handy char pointer (short term usage) */ 401 struct __siov *iovp; /* for PRINT macro */ 402 int flags; /* flags as above */ 403 int ret; /* return value accumulator */ 404 int width; /* width from format (%8d), or 0 */ 405 int prec; /* precision from format (%.3d), or -1 */ 406 char sign; /* sign prefix (' ', '+', '-', or \0) */ 407 char thousands_sep; /* locale specific thousands separator */ 408 const char *grouping; /* locale specific numeric grouping rules */ 409 #ifdef FLOATING_POINT 410 const char *decimal_point; /* locale specific decimal point */ 411 char softsign; /* temporary negative sign for floats */ 412 double _double; /* double precision arguments %[eEfgG] */ 413 int expt; /* integer value of exponent */ 414 int expsize; /* character count for expstr */ 415 int ndig; /* actual number of digits returned by cvt */ 416 char expstr[7]; /* buffer for exponent string */ 417 char *dtoaresult; /* buffer allocated by dtoa */ 418 #endif 419 u_long ulval; /* integer arguments %[diouxX] */ 420 uintmax_t ujval; /* %j, %ll, %q, %t, %z integers */ 421 int base; /* base for [diouxX] conversion */ 422 int dprec; /* a copy of prec if [diouxX], 0 otherwise */ 423 int realsz; /* field size expanded by dprec, sign, etc */ 424 int size; /* size of converted field or string */ 425 int prsize; /* max size of printed field */ 426 char *xdigs; /* digits for [xX] conversion */ 427 #define NIOV 8 428 struct __suio uio; /* output information: summary */ 429 struct __siov iov[NIOV];/* ... and individual io vectors */ 430 char buf[BUF]; /* space for %c, %[diouxX], %[eEfFgG] */ 431 char ox[2]; /* space for 0x hex-prefix */ 432 union arg *argtable; /* args, built due to positional arg */ 433 union arg statargtable[STATIC_ARG_TBL_SIZE]; 434 int nextarg; /* 1-based argument index */ 435 va_list orgap; /* original argument pointer */ 436 437 /* 438 * Choose PADSIZE to trade efficiency vs. size. If larger printf 439 * fields occur frequently, increase PADSIZE and make the initialisers 440 * below longer. 441 */ 442 #define PADSIZE 16 /* pad chunk size */ 443 static char blanks[PADSIZE] = 444 {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '}; 445 static char zeroes[PADSIZE] = 446 {'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'}; 447 448 /* 449 * BEWARE, these `goto error' on error, and PAD uses `n'. 450 */ 451 #define PRINT(ptr, len) { \ 452 iovp->iov_base = __DECONST(void *, ptr); \ 453 iovp->iov_len = (len); \ 454 uio.uio_resid += (len); \ 455 iovp++; \ 456 if (++uio.uio_iovcnt >= NIOV) { \ 457 if (__sprint(fp, &uio)) \ 458 goto error; \ 459 iovp = iov; \ 460 } \ 461 } 462 #define PAD(howmany, with) { \ 463 if ((n = (howmany)) > 0) { \ 464 while (n > PADSIZE) { \ 465 PRINT(with, PADSIZE); \ 466 n -= PADSIZE; \ 467 } \ 468 PRINT(with, n); \ 469 } \ 470 } 471 #define FLUSH() { \ 472 if (uio.uio_resid && __sprint(fp, &uio)) \ 473 goto error; \ 474 uio.uio_iovcnt = 0; \ 475 iovp = iov; \ 476 } 477 478 /* 479 * Get the argument indexed by nextarg. If the argument table is 480 * built, use it to get the argument. If its not, get the next 481 * argument (and arguments must be gotten sequentially). 482 */ 483 #define GETARG(type) \ 484 ((argtable != NULL) ? *((type*)(&argtable[nextarg++])) : \ 485 (nextarg++, va_arg(ap, type))) 486 487 /* 488 * To extend shorts properly, we need both signed and unsigned 489 * argument extraction methods. 490 */ 491 #define SARG() \ 492 (flags&LONGINT ? GETARG(long) : \ 493 flags&SHORTINT ? (long)(short)GETARG(int) : \ 494 flags&CHARINT ? (long)(signed char)GETARG(int) : \ 495 (long)GETARG(int)) 496 #define UARG() \ 497 (flags&LONGINT ? GETARG(u_long) : \ 498 flags&SHORTINT ? (u_long)(u_short)GETARG(int) : \ 499 flags&CHARINT ? (u_long)(u_char)GETARG(int) : \ 500 (u_long)GETARG(u_int)) 501 #define INTMAX_SIZE (INTMAXT|SIZET|PTRDIFFT|LLONGINT) 502 #define SJARG() \ 503 (flags&INTMAXT ? GETARG(intmax_t) : \ 504 flags&SIZET ? (intmax_t)GETARG(size_t) : \ 505 flags&PTRDIFFT ? (intmax_t)GETARG(ptrdiff_t) : \ 506 (intmax_t)GETARG(long long)) 507 #define UJARG() \ 508 (flags&INTMAXT ? GETARG(uintmax_t) : \ 509 flags&SIZET ? (uintmax_t)GETARG(size_t) : \ 510 flags&PTRDIFFT ? (uintmax_t)GETARG(ptrdiff_t) : \ 511 (uintmax_t)GETARG(unsigned long long)) 512 513 /* 514 * Get * arguments, including the form *nn$. Preserve the nextarg 515 * that the argument can be gotten once the type is determined. 516 */ 517 #define GETASTER(val) \ 518 n2 = 0; \ 519 cp = fmt; \ 520 while (is_digit(*cp)) { \ 521 n2 = 10 * n2 + to_digit(*cp); \ 522 cp++; \ 523 } \ 524 if (*cp == '$') { \ 525 int hold = nextarg; \ 526 if (argtable == NULL) { \ 527 argtable = statargtable; \ 528 __find_arguments (fmt0, orgap, &argtable); \ 529 } \ 530 nextarg = n2; \ 531 val = GETARG (int); \ 532 nextarg = hold; \ 533 fmt = ++cp; \ 534 } else { \ 535 val = GETARG (int); \ 536 } 537 538 539 thousands_sep = '\0'; 540 grouping = NULL; 541 #ifdef FLOATING_POINT 542 dtoaresult = NULL; 543 decimal_point = localeconv()->decimal_point; 544 #endif 545 /* sorry, fprintf(read_only_file, "") returns EOF, not 0 */ 546 if (cantwrite(fp)) { 547 return (EOF); 548 } 549 550 /* optimise fprintf(stderr) (and other unbuffered Unix files) */ 551 if ((fp->pub._flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) && 552 fp->pub._fileno >= 0) { 553 return (__sbprintf(fp, fmt0, ap)); 554 } 555 556 fmt = (char *)fmt0; 557 argtable = NULL; 558 nextarg = 1; 559 orgap = ap; 560 uio.uio_iov = iovp = iov; 561 uio.uio_resid = 0; 562 uio.uio_iovcnt = 0; 563 ret = 0; 564 565 /* 566 * Scan the format for conversions (`%' character). 567 */ 568 for (;;) { 569 for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++) 570 /* void */; 571 if ((n = fmt - cp) != 0) { 572 if ((unsigned)ret + n > INT_MAX) { 573 ret = EOF; 574 goto error; 575 } 576 PRINT(cp, n); 577 ret += n; 578 } 579 if (ch == '\0') 580 goto done; 581 fmt++; /* skip over '%' */ 582 583 flags = 0; 584 dprec = 0; 585 width = 0; 586 prec = -1; 587 sign = '\0'; 588 589 rflag: ch = *fmt++; 590 reswitch: switch (ch) { 591 case ' ': 592 /* 593 * ``If the space and + flags both appear, the space 594 * flag will be ignored.'' 595 * -- ANSI X3J11 596 */ 597 if (!sign) 598 sign = ' '; 599 goto rflag; 600 case '#': 601 flags |= ALT; 602 goto rflag; 603 case '*': 604 /* 605 * ``A negative field width argument is taken as a 606 * - flag followed by a positive field width.'' 607 * -- ANSI X3J11 608 * They don't exclude field widths read from args. 609 */ 610 GETASTER (width); 611 if (width >= 0) 612 goto rflag; 613 width = -width; 614 /* FALLTHROUGH */ 615 case '-': 616 flags |= LADJUST; 617 goto rflag; 618 case '+': 619 sign = '+'; 620 goto rflag; 621 case '\'': 622 flags |= GROUPING; 623 thousands_sep = *(localeconv()->thousands_sep); 624 grouping = localeconv()->grouping; 625 goto rflag; 626 case '.': 627 if ((ch = *fmt++) == '*') { 628 GETASTER (n); 629 prec = n < 0 ? -1 : n; 630 goto rflag; 631 } 632 n = 0; 633 while (is_digit(ch)) { 634 n = 10 * n + to_digit(ch); 635 ch = *fmt++; 636 } 637 prec = n < 0 ? -1 : n; 638 goto reswitch; 639 case '0': 640 /* 641 * ``Note that 0 is taken as a flag, not as the 642 * beginning of a field width.'' 643 * -- ANSI X3J11 644 */ 645 flags |= ZEROPAD; 646 goto rflag; 647 case '1': case '2': case '3': case '4': 648 case '5': case '6': case '7': case '8': case '9': 649 n = 0; 650 do { 651 n = 10 * n + to_digit(ch); 652 ch = *fmt++; 653 } while (is_digit(ch)); 654 if (ch == '$') { 655 nextarg = n; 656 if (argtable == NULL) { 657 argtable = statargtable; 658 __find_arguments (fmt0, orgap, 659 &argtable); 660 } 661 goto rflag; 662 } 663 width = n; 664 goto reswitch; 665 #ifdef FLOATING_POINT 666 case 'L': 667 flags |= LONGDBL; 668 goto rflag; 669 #endif 670 case 'h': 671 if (flags & SHORTINT) { 672 flags &= ~SHORTINT; 673 flags |= CHARINT; 674 } else 675 flags |= SHORTINT; 676 goto rflag; 677 case 'j': 678 flags |= INTMAXT; 679 goto rflag; 680 case 'l': 681 if (flags & LONGINT) { 682 flags &= ~LONGINT; 683 flags |= LLONGINT; 684 } else 685 flags |= LONGINT; 686 goto rflag; 687 case 'q': 688 flags |= LLONGINT; 689 goto rflag; 690 case 't': 691 flags |= PTRDIFFT; 692 goto rflag; 693 case 'z': 694 flags |= SIZET; 695 goto rflag; 696 case 'c': 697 *(cp = buf) = GETARG(int); 698 size = 1; 699 sign = '\0'; 700 break; 701 case 'D': 702 flags |= LONGINT; 703 /*FALLTHROUGH*/ 704 case 'd': 705 case 'i': 706 if (flags & INTMAX_SIZE) { 707 ujval = SJARG(); 708 if ((intmax_t)ujval < 0) { 709 ujval = -ujval; 710 sign = '-'; 711 } 712 } else { 713 ulval = SARG(); 714 if ((long)ulval < 0) { 715 ulval = -ulval; 716 sign = '-'; 717 } 718 } 719 base = 10; 720 goto number; 721 #ifdef FLOATING_POINT 722 #ifdef HEXFLOAT 723 case 'a': 724 case 'A': 725 #endif 726 case 'e': 727 case 'E': 728 /* 729 * Grouping apply to %i, %d, %u, %f, %F, %g, %G 730 * conversion specifiers only. For other conversions 731 * behavior is undefined. 732 * -- POSIX 733 */ 734 flags &= ~GROUPING; 735 /*FALLTHROUGH*/ 736 case 'f': 737 case 'F': 738 goto fp_begin; 739 case 'g': 740 case 'G': 741 if (prec == 0) 742 prec = 1; 743 fp_begin: if (prec == -1) 744 prec = DEFPREC; 745 if (flags & LONGDBL) 746 /* XXX this loses precision. */ 747 _double = (double)GETARG(long double); 748 else 749 _double = GETARG(double); 750 /* do this before tricky precision changes */ 751 if (isinf(_double)) { 752 if (_double < 0) 753 sign = '-'; 754 if (isupper(ch)) 755 cp = "INF"; 756 else 757 cp = "inf"; 758 size = 3; 759 break; 760 } 761 if (isnan(_double)) { 762 if (isupper(ch)) 763 cp = "NAN"; 764 else 765 cp = "nan"; 766 size = 3; 767 break; 768 } 769 flags |= FPT; 770 if (dtoaresult != NULL) { 771 free(dtoaresult); 772 dtoaresult = NULL; 773 } 774 cp = cvt(_double, prec, flags, &softsign, 775 &expt, ch, &ndig, &dtoaresult); 776 if (ch == 'g' || ch == 'G') { 777 if (expt <= -4 || expt > prec) 778 ch = (ch == 'g') ? 'e' : 'E'; 779 else 780 ch = 'g'; 781 } 782 if (ch == 'e' || ch == 'E') { 783 --expt; 784 expsize = exponent(expstr, expt, ch); 785 size = expsize + ndig; 786 if (ndig > 1 || flags & ALT) 787 ++size; 788 } else if (ch == 'f' || ch == 'F') { 789 if (expt > 0) { 790 size = expt; 791 if (prec || flags & ALT) 792 size += prec + 1; 793 } else /* "0.X" */ 794 size = prec + 2; 795 } else if (expt >= ndig) { /* fixed g fmt */ 796 size = expt; 797 if (flags & ALT) 798 ++size; 799 } else 800 size = ndig + (expt > 0 ? 801 1 : 2 - expt); 802 803 if (softsign) 804 sign = '-'; 805 break; 806 #endif /* FLOATING_POINT */ 807 case 'n': 808 /* 809 * Assignment-like behavior is specified if the 810 * value overflows or is otherwise unrepresentable. 811 * C99 says to use `signed char' for %hhn conversions. 812 */ 813 if (flags & LLONGINT) 814 *GETARG(long long *) = ret; 815 else if (flags & SIZET) 816 *GETARG(ssize_t *) = (ssize_t)ret; 817 else if (flags & PTRDIFFT) 818 *GETARG(ptrdiff_t *) = ret; 819 else if (flags & INTMAXT) 820 *GETARG(intmax_t *) = ret; 821 else if (flags & LONGINT) 822 *GETARG(long *) = ret; 823 else if (flags & SHORTINT) 824 *GETARG(short *) = ret; 825 else if (flags & CHARINT) 826 *GETARG(signed char *) = ret; 827 else 828 *GETARG(int *) = ret; 829 continue; /* no output */ 830 case 'O': 831 flags |= LONGINT; 832 /*FALLTHROUGH*/ 833 case 'o': 834 if (flags & INTMAX_SIZE) 835 ujval = UJARG(); 836 else 837 ulval = UARG(); 838 base = 8; 839 goto nosign; 840 case 'p': 841 /* 842 * ``The argument shall be a pointer to void. The 843 * value of the pointer is converted to a sequence 844 * of printable characters, in an implementation- 845 * defined manner.'' 846 * -- ANSI X3J11 847 */ 848 ujval = (uintmax_t)(uintptr_t)GETARG(void *); 849 base = 16; 850 xdigs = "0123456789abcdef"; 851 flags = flags | INTMAXT | HEXPREFIX; 852 ch = 'x'; 853 goto nosign; 854 case 's': 855 if ((cp = GETARG(char *)) == NULL) 856 cp = "(null)"; 857 if (prec >= 0) { 858 /* 859 * can't use strlen; can only look for the 860 * NUL in the first `prec' characters, and 861 * strlen() will go further. 862 */ 863 char *p = memchr(cp, 0, (size_t)prec); 864 865 if (p != NULL) { 866 size = p - cp; 867 if (size > prec) 868 size = prec; 869 } else 870 size = prec; 871 } else 872 size = strlen(cp); 873 sign = '\0'; 874 break; 875 case 'U': 876 flags |= LONGINT; 877 /*FALLTHROUGH*/ 878 case 'u': 879 if (flags & INTMAX_SIZE) 880 ujval = UJARG(); 881 else 882 ulval = UARG(); 883 base = 10; 884 goto nosign; 885 case 'X': 886 xdigs = "0123456789ABCDEF"; 887 goto hex; 888 case 'x': 889 xdigs = "0123456789abcdef"; 890 hex: 891 if (flags & INTMAX_SIZE) 892 ujval = UJARG(); 893 else 894 ulval = UARG(); 895 base = 16; 896 /* leading 0x/X only if non-zero */ 897 if (flags & ALT && 898 (flags & INTMAX_SIZE ? ujval != 0 : ulval != 0)) 899 flags |= HEXPREFIX; 900 901 flags &= ~GROUPING; 902 /* unsigned conversions */ 903 nosign: sign = '\0'; 904 /* 905 * ``... diouXx conversions ... if a precision is 906 * specified, the 0 flag will be ignored.'' 907 * -- ANSI X3J11 908 */ 909 number: if ((dprec = prec) >= 0) 910 flags &= ~ZEROPAD; 911 912 /* 913 * ``The result of converting a zero value with an 914 * explicit precision of zero is no characters.'' 915 * -- ANSI X3J11 916 */ 917 cp = buf + BUF; 918 if (flags & INTMAX_SIZE) { 919 if (ujval != 0 || prec != 0) 920 cp = __ujtoa(ujval, cp, base, 921 flags & ALT, xdigs, 922 flags & GROUPING, thousands_sep, 923 grouping); 924 } else { 925 if (ulval != 0 || prec != 0) 926 cp = __ultoa(ulval, cp, base, 927 flags & ALT, xdigs, 928 flags & GROUPING, thousands_sep, 929 grouping); 930 } 931 size = buf + BUF - cp; 932 break; 933 default: /* "%?" prints ?, unless ? is NUL */ 934 if (ch == '\0') 935 goto done; 936 /* pretend it was %c with argument ch */ 937 cp = buf; 938 *cp = ch; 939 size = 1; 940 sign = '\0'; 941 break; 942 } 943 944 /* 945 * All reasonable formats wind up here. At this point, `cp' 946 * points to a string which (if not flags&LADJUST) should be 947 * padded out to `width' places. If flags&ZEROPAD, it should 948 * first be prefixed by any sign or other prefix; otherwise, 949 * it should be blank padded before the prefix is emitted. 950 * After any left-hand padding and prefixing, emit zeroes 951 * required by a decimal [diouxX] precision, then print the 952 * string proper, then emit zeroes required by any leftover 953 * floating precision; finally, if LADJUST, pad with blanks. 954 * 955 * Compute actual size, so we know how much to pad. 956 * size excludes decimal prec; realsz includes it. 957 */ 958 realsz = dprec > size ? dprec : size; 959 if (sign) 960 realsz++; 961 else if (flags & HEXPREFIX) 962 realsz += 2; 963 964 prsize = width > realsz ? width : realsz; 965 if ((unsigned)ret + prsize > INT_MAX) { 966 ret = EOF; 967 goto error; 968 } 969 970 /* right-adjusting blank padding */ 971 if ((flags & (LADJUST|ZEROPAD)) == 0) 972 PAD(width - realsz, blanks); 973 974 /* prefix */ 975 if (sign) { 976 PRINT(&sign, 1); 977 } else if (flags & HEXPREFIX) { 978 ox[0] = '0'; 979 ox[1] = ch; 980 PRINT(ox, 2); 981 } 982 983 /* right-adjusting zero padding */ 984 if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) 985 PAD(width - realsz, zeroes); 986 987 /* leading zeroes from decimal precision */ 988 PAD(dprec - size, zeroes); 989 990 /* the string or number proper */ 991 #ifdef FLOATING_POINT 992 if ((flags & FPT) == 0) { 993 PRINT(cp, size); 994 } else { /* glue together f_p fragments */ 995 if (ch >= 'f') { /* 'f' or 'g' */ 996 if (_double == 0) { 997 /* kludge for __dtoa irregularity */ 998 PRINT("0", 1); 999 if (expt < ndig || (flags & ALT) != 0) { 1000 PRINT(decimal_point, 1); 1001 PAD(ndig - 1, zeroes); 1002 } 1003 } else if (expt <= 0) { 1004 PRINT("0", 1); 1005 PRINT(decimal_point, 1); 1006 PAD(-expt, zeroes); 1007 PRINT(cp, ndig); 1008 } else if (expt >= ndig) { 1009 PRINT(cp, ndig); 1010 PAD(expt - ndig, zeroes); 1011 if (flags & ALT) 1012 PRINT(decimal_point, 1); 1013 } else { 1014 PRINT(cp, expt); 1015 cp += expt; 1016 PRINT(decimal_point, 1); 1017 PRINT(cp, ndig-expt); 1018 } 1019 } else { /* 'e' or 'E' */ 1020 if (ndig > 1 || flags & ALT) { 1021 ox[0] = *cp++; 1022 ox[1] = *decimal_point; 1023 PRINT(ox, 2); 1024 if (_double) { 1025 PRINT(cp, ndig-1); 1026 } else /* 0.[0..] */ 1027 /* __dtoa irregularity */ 1028 PAD(ndig - 1, zeroes); 1029 } else /* XeYYY */ 1030 PRINT(cp, 1); 1031 PRINT(expstr, expsize); 1032 } 1033 } 1034 #else 1035 PRINT(cp, size); 1036 #endif 1037 /* left-adjusting padding (always blank) */ 1038 if (flags & LADJUST) 1039 PAD(width - realsz, blanks); 1040 1041 /* finally, adjust ret */ 1042 ret += prsize; 1043 1044 FLUSH(); /* copy out the I/O vectors */ 1045 } 1046 done: 1047 FLUSH(); 1048 error: 1049 #ifdef FLOATING_POINT 1050 if (dtoaresult != NULL) 1051 free(dtoaresult); 1052 #endif 1053 if (__sferror(fp)) 1054 ret = EOF; 1055 if ((argtable != NULL) && (argtable != statargtable)) 1056 free (argtable); 1057 return (ret); 1058 /* NOTREACHED */ 1059 } 1060 1061 /* 1062 * Find all arguments when a positional parameter is encountered. Returns a 1063 * table, indexed by argument number, of pointers to each arguments. The 1064 * initial argument table should be an array of STATIC_ARG_TBL_SIZE entries. 1065 * It will be replaces with a malloc-ed one if it overflows. 1066 */ 1067 static void 1068 __find_arguments (const char *fmt0, va_list ap, union arg **argtable) 1069 { 1070 char *fmt; /* format string */ 1071 int ch; /* character from fmt */ 1072 int n, n2; /* handy integer (short term usage) */ 1073 char *cp; /* handy char pointer (short term usage) */ 1074 int flags; /* flags as above */ 1075 int width; /* width from format (%8d), or 0 */ 1076 enum typeid *typetable; /* table of types */ 1077 enum typeid stattypetable[STATIC_ARG_TBL_SIZE]; 1078 int tablesize; /* current size of type table */ 1079 int tablemax; /* largest used index in table */ 1080 int nextarg; /* 1-based argument index */ 1081 1082 /* 1083 * Add an argument type to the table, expanding if necessary. 1084 */ 1085 #define ADDTYPE(type) \ 1086 ((nextarg >= tablesize) ? \ 1087 __grow_type_table(nextarg, &typetable, &tablesize) : 0, \ 1088 (nextarg > tablemax) ? tablemax = nextarg : 0, \ 1089 typetable[nextarg++] = type) 1090 1091 #define ADDSARG() \ 1092 ((flags&INTMAXT) ? ADDTYPE(T_INTMAXT) : \ 1093 ((flags&SIZET) ? ADDTYPE(T_SIZET) : \ 1094 ((flags&PTRDIFFT) ? ADDTYPE(T_PTRDIFFT) : \ 1095 ((flags&LLONGINT) ? ADDTYPE(T_LLONG) : \ 1096 ((flags&LONGINT) ? ADDTYPE(T_LONG) : ADDTYPE(T_INT)))))) 1097 1098 #define ADDUARG() \ 1099 ((flags&INTMAXT) ? ADDTYPE(T_UINTMAXT) : \ 1100 ((flags&SIZET) ? ADDTYPE(T_SIZET) : \ 1101 ((flags&PTRDIFFT) ? ADDTYPE(T_PTRDIFFT) : \ 1102 ((flags&LLONGINT) ? ADDTYPE(T_U_LLONG) : \ 1103 ((flags&LONGINT) ? ADDTYPE(T_U_LONG) : ADDTYPE(T_U_INT)))))) 1104 1105 /* 1106 * Add * arguments to the type array. 1107 */ 1108 #define ADDASTER() \ 1109 n2 = 0; \ 1110 cp = fmt; \ 1111 while (is_digit(*cp)) { \ 1112 n2 = 10 * n2 + to_digit(*cp); \ 1113 cp++; \ 1114 } \ 1115 if (*cp == '$') { \ 1116 int hold = nextarg; \ 1117 nextarg = n2; \ 1118 ADDTYPE (T_INT); \ 1119 nextarg = hold; \ 1120 fmt = ++cp; \ 1121 } else { \ 1122 ADDTYPE (T_INT); \ 1123 } 1124 fmt = (char *)fmt0; 1125 typetable = stattypetable; 1126 tablesize = STATIC_ARG_TBL_SIZE; 1127 tablemax = 0; 1128 nextarg = 1; 1129 memset (typetable, T_UNUSED, STATIC_ARG_TBL_SIZE); 1130 1131 /* 1132 * Scan the format for conversions (`%' character). 1133 */ 1134 for (;;) { 1135 for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++) 1136 /* void */; 1137 if (ch == '\0') 1138 goto done; 1139 fmt++; /* skip over '%' */ 1140 1141 flags = 0; 1142 width = 0; 1143 1144 rflag: ch = *fmt++; 1145 reswitch: switch (ch) { 1146 case ' ': 1147 case '#': 1148 goto rflag; 1149 case '*': 1150 ADDASTER (); 1151 goto rflag; 1152 case '-': 1153 case '+': 1154 case '\'': 1155 goto rflag; 1156 case '.': 1157 if ((ch = *fmt++) == '*') { 1158 ADDASTER (); 1159 goto rflag; 1160 } 1161 while (is_digit(ch)) { 1162 ch = *fmt++; 1163 } 1164 goto reswitch; 1165 case '0': 1166 goto rflag; 1167 case '1': case '2': case '3': case '4': 1168 case '5': case '6': case '7': case '8': case '9': 1169 n = 0; 1170 do { 1171 n = 10 * n + to_digit(ch); 1172 ch = *fmt++; 1173 } while (is_digit(ch)); 1174 if (ch == '$') { 1175 nextarg = n; 1176 goto rflag; 1177 } 1178 width = n; 1179 goto reswitch; 1180 #ifdef FLOATING_POINT 1181 case 'L': 1182 flags |= LONGDBL; 1183 goto rflag; 1184 #endif 1185 case 'h': 1186 if (flags & SHORTINT) { 1187 flags &= ~SHORTINT; 1188 flags |= CHARINT; 1189 } else 1190 flags |= SHORTINT; 1191 goto rflag; 1192 case 'j': 1193 flags |= INTMAXT; 1194 goto rflag; 1195 case 'l': 1196 if (flags & LONGINT) { 1197 flags &= ~LONGINT; 1198 flags |= LLONGINT; 1199 } else 1200 flags |= LONGINT; 1201 goto rflag; 1202 case 'q': 1203 flags |= LLONGINT; 1204 goto rflag; 1205 case 't': 1206 flags |= PTRDIFFT; 1207 goto rflag; 1208 case 'z': 1209 flags |= SIZET; 1210 goto rflag; 1211 case 'c': 1212 ADDTYPE(T_INT); 1213 break; 1214 case 'D': 1215 flags |= LONGINT; 1216 /*FALLTHROUGH*/ 1217 case 'd': 1218 case 'i': 1219 ADDSARG(); 1220 break; 1221 #ifdef FLOATING_POINT 1222 #ifdef HEXFLOAT 1223 case 'a': 1224 case 'A': 1225 #endif 1226 case 'e': 1227 case 'E': 1228 case 'f': 1229 case 'g': 1230 case 'G': 1231 if (flags & LONGDBL) 1232 ADDTYPE(T_LONG_DOUBLE); 1233 else 1234 ADDTYPE(T_DOUBLE); 1235 break; 1236 #endif /* FLOATING_POINT */ 1237 case 'n': 1238 if (flags & INTMAXT) 1239 ADDTYPE(TP_INTMAXT); 1240 else if (flags & PTRDIFFT) 1241 ADDTYPE(TP_PTRDIFFT); 1242 else if (flags & SIZET) 1243 ADDTYPE(TP_SIZET); 1244 else if (flags & LLONGINT) 1245 ADDTYPE(TP_LLONG); 1246 else if (flags & LONGINT) 1247 ADDTYPE(TP_LONG); 1248 else if (flags & SHORTINT) 1249 ADDTYPE(TP_SHORT); 1250 else if (flags & CHARINT) 1251 ADDTYPE(TP_SCHAR); 1252 else 1253 ADDTYPE(TP_INT); 1254 continue; /* no output */ 1255 case 'O': 1256 flags |= LONGINT; 1257 /*FALLTHROUGH*/ 1258 case 'o': 1259 ADDUARG(); 1260 break; 1261 case 'p': 1262 ADDTYPE(TP_VOID); 1263 break; 1264 case 's': 1265 ADDTYPE(TP_CHAR); 1266 break; 1267 case 'U': 1268 flags |= LONGINT; 1269 /*FALLTHROUGH*/ 1270 case 'u': 1271 case 'X': 1272 case 'x': 1273 ADDUARG(); 1274 break; 1275 default: /* "%?" prints ?, unless ? is NUL */ 1276 if (ch == '\0') 1277 goto done; 1278 break; 1279 } 1280 } 1281 done: 1282 /* 1283 * Build the argument table. 1284 */ 1285 if (tablemax >= STATIC_ARG_TBL_SIZE) { 1286 *argtable = (union arg *) 1287 malloc(sizeof(union arg) * (tablemax + 1)); 1288 } 1289 (*argtable)[0].intarg = 0; 1290 for (n = 1; n <= tablemax; n++) { 1291 switch (typetable [n]) { 1292 case T_UNUSED: /* "whoops" */ 1293 case T_INT: 1294 (*argtable)[n].intarg = va_arg(ap, int); 1295 break; 1296 case TP_SCHAR: 1297 (*argtable) [n].pschararg = va_arg (ap, signed char *); 1298 case TP_SHORT: 1299 (*argtable)[n].pshortarg = va_arg(ap, short *); 1300 break; 1301 case T_U_INT: 1302 (*argtable)[n].uintarg = va_arg(ap, unsigned int); 1303 break; 1304 case TP_INT: 1305 (*argtable)[n].pintarg = va_arg(ap, int *); 1306 break; 1307 case T_LONG: 1308 (*argtable)[n].longarg = va_arg(ap, long); 1309 break; 1310 case T_U_LONG: 1311 (*argtable)[n].ulongarg = va_arg(ap, unsigned long); 1312 break; 1313 case TP_LONG: 1314 (*argtable)[n].plongarg = va_arg(ap, long *); 1315 break; 1316 case T_LLONG: 1317 (*argtable)[n].longlongarg = va_arg(ap, long long); 1318 break; 1319 case T_U_LLONG: 1320 (*argtable)[n].ulonglongarg = va_arg(ap, unsigned long long); 1321 break; 1322 case TP_LLONG: 1323 (*argtable)[n].plonglongarg = va_arg(ap, long long *); 1324 break; 1325 case T_PTRDIFFT: 1326 (*argtable)[n].ptrdiffarg = va_arg(ap, ptrdiff_t); 1327 break; 1328 case TP_PTRDIFFT: 1329 (*argtable)[n].pptrdiffarg = va_arg(ap, ptrdiff_t *); 1330 break; 1331 case T_SIZET: 1332 (*argtable)[n].sizearg = va_arg(ap, size_t); 1333 break; 1334 case TP_SIZET: 1335 (*argtable)[n].psizearg = va_arg(ap, ssize_t *); 1336 break; 1337 case T_INTMAXT: 1338 (*argtable)[n].intmaxarg = va_arg(ap, intmax_t); 1339 break; 1340 case T_UINTMAXT: 1341 (*argtable)[n].uintmaxarg = va_arg(ap, uintmax_t); 1342 break; 1343 case TP_INTMAXT: 1344 (*argtable)[n].pintmaxarg = va_arg (ap, intmax_t *); 1345 break; 1346 case T_DOUBLE: 1347 (*argtable)[n].doublearg = va_arg(ap, double); 1348 break; 1349 case T_LONG_DOUBLE: 1350 (*argtable)[n].longdoublearg = va_arg(ap, long double); 1351 break; 1352 case TP_CHAR: 1353 (*argtable)[n].pchararg = va_arg(ap, char *); 1354 break; 1355 case TP_VOID: 1356 (*argtable)[n].pvoidarg = va_arg(ap, void *); 1357 break; 1358 } 1359 } 1360 1361 if ((typetable != NULL) && (typetable != stattypetable)) 1362 free (typetable); 1363 } 1364 1365 /* 1366 * Increase the size of the type table. 1367 */ 1368 static void 1369 __grow_type_table(int nextarg, enum typeid **typetable, int *tablesize) 1370 { 1371 enum typeid * const oldtable = *typetable; 1372 const int oldsize = *tablesize; 1373 enum typeid *newtable; 1374 int newsize = oldsize * 2; 1375 1376 if (newsize < nextarg + 1) 1377 newsize = nextarg + 1; 1378 if (oldsize == STATIC_ARG_TBL_SIZE) { 1379 if ((newtable = malloc(newsize)) == NULL) 1380 abort(); /* XXX handle better */ 1381 bcopy(oldtable, newtable, oldsize); 1382 } else { 1383 if ((newtable = reallocf(oldtable, newsize)) == NULL) 1384 abort(); /* XXX handle better */ 1385 } 1386 memset(&newtable[oldsize], T_UNUSED, newsize - oldsize); 1387 1388 *typetable = newtable; 1389 *tablesize = newsize; 1390 } 1391 1392 1393 #ifdef FLOATING_POINT 1394 1395 extern char *__dtoa (double, int, int, int *, int *, char **, char **); 1396 1397 static char * 1398 cvt(double value, int ndigits, int flags, char *sign, int *decpt, 1399 int ch, int *length, char **dtoaresultp) 1400 { 1401 int mode, dsgn; 1402 char *digits, *bp, *rve; 1403 1404 if (ch == 'f') 1405 mode = 3; /* ndigits after the decimal point */ 1406 else { 1407 /* 1408 * To obtain ndigits after the decimal point for the 'e' 1409 * and 'E' formats, round to ndigits + 1 significant 1410 * figures. 1411 */ 1412 if (ch == 'e' || ch == 'E') 1413 ndigits++; 1414 mode = 2; /* ndigits significant digits */ 1415 } 1416 digits = __dtoa(value, mode, ndigits, decpt, &dsgn, &rve, dtoaresultp); 1417 *sign = dsgn != 0; 1418 if ((ch != 'g' && ch != 'G') || flags & ALT) { 1419 /* print trailing zeros */ 1420 bp = digits + ndigits; 1421 if (ch == 'f') { 1422 if (*digits == '0' && value) 1423 *decpt = -ndigits + 1; 1424 bp += *decpt; 1425 } 1426 if (value == 0) /* kludge for __dtoa irregularity */ 1427 rve = bp; 1428 while (rve < bp) 1429 *rve++ = '0'; 1430 } 1431 *length = rve - digits; 1432 return (digits); 1433 } 1434 1435 static int 1436 exponent(char *p0, int exp, int fmtch) 1437 { 1438 char *p, *t; 1439 char expbuf[MAXEXP]; 1440 1441 p = p0; 1442 *p++ = fmtch; 1443 if (exp < 0) { 1444 exp = -exp; 1445 *p++ = '-'; 1446 } 1447 else 1448 *p++ = '+'; 1449 t = expbuf + MAXEXP; 1450 if (exp > 9) { 1451 do { 1452 *--t = to_char(exp % 10); 1453 } while ((exp /= 10) > 9); 1454 *--t = to_char(exp); 1455 for (; t < expbuf + MAXEXP; *p++ = *t++); 1456 } 1457 else { 1458 *p++ = '0'; 1459 *p++ = to_char(exp); 1460 } 1461 return (p - p0); 1462 } 1463 #endif /* FLOATING_POINT */ 1464