vfprintf.c revision 1.46.4.1 1 /* $NetBSD: vfprintf.c,v 1.46.4.1 2005/06/01 15:50:34 riz 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 1.46.4.1 2005/06/01 15:50:34 riz 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 static int
77 __sprint(fp, uio)
78 FILE *fp;
79 struct __suio *uio;
80 {
81 int err;
82
83 _DIAGASSERT(fp != NULL);
84 _DIAGASSERT(uio != NULL);
85
86 if (uio->uio_resid == 0) {
87 uio->uio_iovcnt = 0;
88 return (0);
89 }
90 err = __sfvwrite(fp, uio);
91 uio->uio_resid = 0;
92 uio->uio_iovcnt = 0;
93 return (err);
94 }
95
96 /*
97 * Helper function for `fprintf to unbuffered unix file': creates a
98 * temporary buffer. We only work on write-only files; this avoids
99 * worries about ungetc buffers and so forth.
100 */
101 static int
102 __sbprintf(fp, fmt, ap)
103 FILE *fp;
104 const char *fmt;
105 va_list ap;
106 {
107 int ret;
108 FILE fake;
109 struct __sfileext fakeext;
110 unsigned char buf[BUFSIZ];
111
112 _DIAGASSERT(fp != NULL);
113 _DIAGASSERT(fmt != NULL);
114
115 _FILEEXT_SETUP(&fake, &fakeext);
116
117 /* copy the important variables */
118 fake._flags = fp->_flags & ~__SNBF;
119 fake._file = fp->_file;
120 fake._cookie = fp->_cookie;
121 fake._write = fp->_write;
122
123 /* set up the buffer */
124 fake._bf._base = fake._p = buf;
125 fake._bf._size = fake._w = sizeof(buf);
126 fake._lbfsize = 0; /* not actually used, but Just In Case */
127
128 /* do the work, then copy any error status */
129 ret = vfprintf(&fake, fmt, ap);
130 if (ret >= 0 && fflush(&fake))
131 ret = -1;
132 if (fake._flags & __SERR)
133 fp->_flags |= __SERR;
134 return (ret);
135 }
136
137
138 #ifdef FLOATING_POINT
139 #include <locale.h>
140 #include <math.h>
141 #include "floatio.h"
142
143 #define BUF (MAXEXP+MAXFRACT+1) /* + decimal point */
144 #define DEFPREC 6
145
146 static char *cvt __P((double, int, int, char *, int *, int, int *));
147 static int exponent __P((char *, int, int));
148
149 #else /* no FLOATING_POINT */
150
151 #define BUF 40
152
153 #endif /* FLOATING_POINT */
154
155 /*
156 * Macros for converting digits to letters and vice versa
157 */
158 #define to_digit(c) ((c) - '0')
159 #define is_digit(c) ((unsigned)to_digit(c) <= 9)
160 #define to_char(n) ((char)((n) + '0'))
161
162 /*
163 * Flags used during conversion.
164 */
165 #define ALT 0x001 /* alternate form */
166 #define HEXPREFIX 0x002 /* add 0x or 0X prefix */
167 #define LADJUST 0x004 /* left adjustment */
168 #define LONGDBL 0x008 /* long double; unimplemented */
169 #define LONGINT 0x010 /* long integer */
170 #define QUADINT 0x020 /* quad integer */
171 #define SHORTINT 0x040 /* short integer */
172 #define MAXINT 0x080 /* (unsigned) intmax_t */
173 #define PTRINT 0x100 /* (unsigned) ptrdiff_t */
174 #define SIZEINT 0x200 /* (signed) size_t */
175 #define ZEROPAD 0x400 /* zero (as opposed to blank) pad */
176 #define FPT 0x800 /* Floating point number */
177
178 int
179 vfprintf(fp, fmt0, ap)
180 FILE *fp;
181 const char *fmt0;
182 _BSD_VA_LIST_ ap;
183 {
184 int ret;
185
186 FLOCKFILE(fp);
187 ret = vfprintf_unlocked(fp, fmt0, ap);
188 FUNLOCKFILE(fp);
189
190 return ret;
191 }
192
193
194
195 int
196 vfprintf_unlocked(fp, fmt0, ap)
197 FILE *fp;
198 const char *fmt0;
199 _BSD_VA_LIST_ ap;
200 {
201 const char *fmt;/* format string */
202 int ch; /* character from fmt */
203 int n, m; /* handy integers (short term usage) */
204 const char *cp; /* handy char pointer (short term usage) */
205 char *bp; /* handy char pointer (short term usage) */
206 struct __siov *iovp;/* for PRINT macro */
207 int flags; /* flags as above */
208 int ret; /* return value accumulator */
209 int width; /* width from format (%8d), or 0 */
210 int prec; /* precision from format (%.3d), or -1 */
211 char sign; /* sign prefix (' ', '+', '-', or \0) */
212 wchar_t wc;
213 mbstate_t ps;
214 #ifdef FLOATING_POINT
215 char *decimal_point = localeconv()->decimal_point;
216 char softsign; /* temporary negative sign for floats */
217 double _double; /* double precision arguments %[eEfgG] */
218 int expt; /* integer value of exponent */
219 int expsize = 0; /* character count for expstr */
220 int ndig; /* actual number of digits returned by cvt */
221 char expstr[7]; /* buffer for exponent string */
222 #endif
223
224 #ifdef __GNUC__ /* gcc has builtin quad type (long long) SOS */
225 #define quad_t long long
226 #define u_quad_t unsigned long long
227 #endif
228
229 #define INTMAX_T intmax_t
230 #define UINTMAX_T uintmax_t
231
232 UINTMAX_T _uintmax; /* integer arguments %[diouxX] */
233 enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */
234 int dprec; /* a copy of prec if [diouxX], 0 otherwise */
235 int realsz; /* field size expanded by dprec */
236 int size; /* size of converted field or string */
237 char *xdigs = NULL; /* digits for [xX] conversion */
238 #define NIOV 8
239 struct __suio uio; /* output information: summary */
240 struct __siov iov[NIOV];/* ... and individual io vectors */
241 char buf[BUF]; /* space for %c, %[diouxX], %[eEfgG] */
242 char ox[2]; /* space for 0x hex-prefix */
243
244 /*
245 * Choose PADSIZE to trade efficiency vs. size. If larger printf
246 * fields occur frequently, increase PADSIZE and make the initialisers
247 * below longer.
248 */
249 #define PADSIZE 16 /* pad chunk size */
250 static const char blanks[PADSIZE] =
251 {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '};
252 static const char zeroes[PADSIZE] =
253 {'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'};
254
255 /*
256 * BEWARE, these `goto error' on error, and PAD uses `n'.
257 */
258 #define PRINT(ptr, len) { \
259 iovp->iov_base = __UNCONST(ptr); \
260 iovp->iov_len = (len); \
261 uio.uio_resid += (len); \
262 iovp++; \
263 if (++uio.uio_iovcnt >= NIOV) { \
264 if (__sprint(fp, &uio)) \
265 goto error; \
266 iovp = iov; \
267 } \
268 }
269 #define PAD(howmany, with) { \
270 if ((n = (howmany)) > 0) { \
271 while (n > PADSIZE) { \
272 PRINT(with, PADSIZE); \
273 n -= PADSIZE; \
274 } \
275 PRINT(with, n); \
276 } \
277 }
278 #define FLUSH() { \
279 if (uio.uio_resid && __sprint(fp, &uio)) \
280 goto error; \
281 uio.uio_iovcnt = 0; \
282 iovp = iov; \
283 }
284
285 /*
286 * To extend shorts properly, we need both signed and unsigned
287 * argument extraction methods.
288 */
289 #define SARG() \
290 (flags&MAXINT ? va_arg(ap, intmax_t) : \
291 flags&PTRINT ? va_arg(ap, ptrdiff_t) : \
292 flags&SIZEINT ? va_arg(ap, ssize_t) : /* XXX */ \
293 flags&QUADINT ? va_arg(ap, quad_t) : \
294 flags&LONGINT ? va_arg(ap, long) : \
295 flags&SHORTINT ? (long)(short)va_arg(ap, int) : \
296 (long)va_arg(ap, int))
297 #define UARG() \
298 (flags&MAXINT ? va_arg(ap, uintmax_t) : \
299 flags&PTRINT ? va_arg(ap, uintptr_t) : /* XXX */ \
300 flags&SIZEINT ? va_arg(ap, size_t) : \
301 flags&QUADINT ? va_arg(ap, u_quad_t) : \
302 flags&LONGINT ? va_arg(ap, u_long) : \
303 flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \
304 (u_long)va_arg(ap, u_int))
305
306 _DIAGASSERT(fp != NULL);
307 _DIAGASSERT(fmt0 != NULL);
308
309 _SET_ORIENTATION(fp, -1);
310
311 /* sorry, fprintf(read_only_file, "") returns -1, not 0 */
312 if (cantwrite(fp)) {
313 errno = EBADF;
314 return (-1);
315 }
316
317 /* optimise fprintf(stderr) (and other unbuffered Unix files) */
318 if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) &&
319 fp->_file >= 0) {
320 ret = __sbprintf(fp, fmt0, ap);
321 return (ret);
322 }
323
324 fmt = fmt0;
325 uio.uio_iov = iovp = iov;
326 uio.uio_resid = 0;
327 uio.uio_iovcnt = 0;
328 ret = 0;
329
330 memset(&ps, 0, sizeof(ps));
331
332 /*
333 * Scan the format for conversions (`%' character).
334 */
335 for (;;) {
336 cp = fmt;
337 while ((n = mbrtowc(&wc, fmt, MB_CUR_MAX, &ps)) > 0) {
338 fmt += n;
339 if (wc == '%') {
340 fmt--;
341 break;
342 }
343 }
344 if ((m = fmt - cp) != 0) {
345 PRINT(cp, m);
346 ret += m;
347 }
348 if (n <= 0)
349 goto done;
350 fmt++; /* skip over '%' */
351
352 flags = 0;
353 dprec = 0;
354 width = 0;
355 prec = -1;
356 sign = '\0';
357
358 rflag: ch = *fmt++;
359 reswitch: switch (ch) {
360 case ' ':
361 /*
362 * ``If the space and + flags both appear, the space
363 * flag will be ignored.''
364 * -- ANSI X3J11
365 */
366 if (!sign)
367 sign = ' ';
368 goto rflag;
369 case '#':
370 flags |= ALT;
371 goto rflag;
372 case '*':
373 /*
374 * ``A negative field width argument is taken as a
375 * - flag followed by a positive field width.''
376 * -- ANSI X3J11
377 * They don't exclude field widths read from args.
378 */
379 if ((width = va_arg(ap, int)) >= 0)
380 goto rflag;
381 width = -width;
382 /* FALLTHROUGH */
383 case '-':
384 flags |= LADJUST;
385 goto rflag;
386 case '+':
387 sign = '+';
388 goto rflag;
389 case '.':
390 if ((ch = *fmt++) == '*') {
391 n = va_arg(ap, int);
392 prec = n < 0 ? -1 : n;
393 goto rflag;
394 }
395 n = 0;
396 while (is_digit(ch)) {
397 n = 10 * n + to_digit(ch);
398 ch = *fmt++;
399 }
400 prec = n < 0 ? -1 : n;
401 goto reswitch;
402 case '0':
403 /*
404 * ``Note that 0 is taken as a flag, not as the
405 * beginning of a field width.''
406 * -- ANSI X3J11
407 */
408 flags |= ZEROPAD;
409 goto rflag;
410 case '1': case '2': case '3': case '4':
411 case '5': case '6': case '7': case '8': case '9':
412 n = 0;
413 do {
414 n = 10 * n + to_digit(ch);
415 ch = *fmt++;
416 } while (is_digit(ch));
417 width = n;
418 goto reswitch;
419 #ifdef FLOATING_POINT
420 case 'L':
421 flags |= LONGDBL;
422 goto rflag;
423 #endif
424 case 'h':
425 flags |= SHORTINT;
426 goto rflag;
427 case 'j':
428 flags |= MAXINT;
429 goto rflag;
430 case 'l':
431 if (*fmt == 'l') {
432 fmt++;
433 flags |= QUADINT;
434 } else {
435 flags |= LONGINT;
436 }
437 goto rflag;
438 case 'q':
439 flags |= QUADINT;
440 goto rflag;
441 case 't':
442 flags |= PTRINT;
443 goto rflag;
444 case 'z':
445 flags |= SIZEINT;
446 goto rflag;
447 case 'c':
448 *buf = va_arg(ap, int);
449 cp = buf;
450 size = 1;
451 sign = '\0';
452 break;
453 case 'D':
454 flags |= LONGINT;
455 /*FALLTHROUGH*/
456 case 'd':
457 case 'i':
458 _uintmax = SARG();
459 if ((intmax_t)_uintmax < 0) {
460 _uintmax = -_uintmax;
461 sign = '-';
462 }
463 base = DEC;
464 goto number;
465 #ifdef FLOATING_POINT
466 case 'e':
467 case 'E':
468 case 'f':
469 case 'F':
470 case 'g':
471 case 'G':
472 if (prec == -1) {
473 prec = DEFPREC;
474 } else if ((ch == 'g' || ch == 'G') && prec == 0) {
475 prec = 1;
476 }
477
478 if (flags & LONGDBL) {
479 _double = (double) va_arg(ap, long double);
480 } else {
481 _double = va_arg(ap, double);
482 }
483
484 /* do this before tricky precision changes */
485 if (isinf(_double)) {
486 if (_double < 0)
487 sign = '-';
488 if (ch == 'E' || ch == 'F' || ch == 'G')
489 cp = "INF";
490 else
491 cp = "inf";
492 size = 3;
493 break;
494 }
495 if (isnan(_double)) {
496 if (ch == 'E' || ch == 'F' || ch == 'G')
497 cp = "NAN";
498 else
499 cp = "nan";
500 size = 3;
501 break;
502 }
503
504 flags |= FPT;
505 cp = cvt(_double, prec, flags, &softsign,
506 &expt, ch, &ndig);
507 if (ch == 'g' || ch == 'G') {
508 if (expt <= -4 || expt > prec)
509 ch = (ch == 'g') ? 'e' : 'E';
510 else
511 ch = 'g';
512 }
513 if (ch == 'e' || ch == 'E') {
514 --expt;
515 expsize = exponent(expstr, expt, ch);
516 size = expsize + ndig;
517 if (ndig > 1 || flags & ALT)
518 ++size;
519 } else if (ch == 'f' || ch == 'F') {
520 if (expt > 0) {
521 size = expt;
522 if (prec || flags & ALT)
523 size += prec + 1;
524 } else /* "0.X" */
525 size = prec + 2;
526 } else if (expt >= ndig) { /* fixed g fmt */
527 size = expt;
528 if (flags & ALT)
529 ++size;
530 } else
531 size = ndig + (expt > 0 ?
532 1 : 2 - expt);
533
534 if (softsign)
535 sign = '-';
536 break;
537 #endif /* FLOATING_POINT */
538 case 'n':
539 if (flags & MAXINT)
540 *va_arg(ap, intmax_t *) = ret;
541 else if (flags & PTRINT)
542 *va_arg(ap, ptrdiff_t *) = ret;
543 else if (flags & SIZEINT)
544 *va_arg(ap, ssize_t *) = ret; /* XXX */
545 else if (flags & QUADINT)
546 *va_arg(ap, quad_t *) = ret;
547 else if (flags & LONGINT)
548 *va_arg(ap, long *) = ret;
549 else if (flags & SHORTINT)
550 *va_arg(ap, short *) = ret;
551 else
552 *va_arg(ap, int *) = ret;
553 continue; /* no output */
554 case 'O':
555 flags |= LONGINT;
556 /*FALLTHROUGH*/
557 case 'o':
558 _uintmax = UARG();
559 base = OCT;
560 goto nosign;
561 case 'p':
562 /*
563 * ``The argument shall be a pointer to void. The
564 * value of the pointer is converted to a sequence
565 * of printable characters, in an implementation-
566 * defined manner.''
567 * -- ANSI X3J11
568 */
569 /* NOSTRICT */
570 _uintmax = (u_long)va_arg(ap, void *);
571 base = HEX;
572 xdigs = "0123456789abcdef";
573 flags |= HEXPREFIX;
574 ch = 'x';
575 goto nosign;
576 case 's':
577 if ((cp = va_arg(ap, char *)) == NULL)
578 cp = "(null)";
579 if (prec >= 0) {
580 /*
581 * can't use strlen; can only look for the
582 * NUL in the first `prec' characters, and
583 * strlen() will go further.
584 */
585 char *p = memchr(cp, 0, (size_t)prec);
586
587 if (p != NULL) {
588 size = p - cp;
589 if (size > prec)
590 size = prec;
591 } else
592 size = prec;
593 } else
594 size = strlen(cp);
595 sign = '\0';
596 break;
597 case 'U':
598 flags |= LONGINT;
599 /*FALLTHROUGH*/
600 case 'u':
601 _uintmax = UARG();
602 base = DEC;
603 goto nosign;
604 case 'X':
605 xdigs = "0123456789ABCDEF";
606 goto hex;
607 case 'x':
608 xdigs = "0123456789abcdef";
609 hex: _uintmax = UARG();
610 base = HEX;
611 /* leading 0x/X only if non-zero */
612 if (flags & ALT && _uintmax != 0)
613 flags |= HEXPREFIX;
614
615 /* unsigned conversions */
616 nosign: sign = '\0';
617 /*
618 * ``... diouXx conversions ... if a precision is
619 * specified, the 0 flag will be ignored.''
620 * -- ANSI X3J11
621 */
622 number: if ((dprec = prec) >= 0)
623 flags &= ~ZEROPAD;
624
625 /*
626 * ``The result of converting a zero value with an
627 * explicit precision of zero is no characters.''
628 * -- ANSI X3J11
629 */
630 bp = buf + BUF;
631 if (_uintmax != 0 || prec != 0) {
632 /*
633 * Unsigned mod is hard, and unsigned mod
634 * by a constant is easier than that by
635 * a variable; hence this switch.
636 */
637 switch (base) {
638 case OCT:
639 do {
640 *--bp = to_char(_uintmax & 7);
641 _uintmax >>= 3;
642 } while (_uintmax);
643 /* handle octal leading 0 */
644 if (flags & ALT && *bp != '0')
645 *--bp = '0';
646 break;
647
648 case DEC:
649 /* many numbers are 1 digit */
650 while (_uintmax >= 10) {
651 *--bp = to_char(_uintmax % 10);
652 _uintmax /= 10;
653 }
654 *--bp = to_char(_uintmax);
655 break;
656
657 case HEX:
658 do {
659 *--bp = xdigs[(size_t)
660 (_uintmax & 15)];
661 _uintmax >>= 4;
662 } while (_uintmax);
663 break;
664
665 default:
666 cp = "bug in vfprintf: bad base";
667 size = strlen(cp);
668 goto skipsize;
669 }
670 }
671 cp = bp;
672 size = buf + BUF - bp;
673 skipsize:
674 break;
675 default: /* "%?" prints ?, unless ? is NUL */
676 if (ch == '\0')
677 goto done;
678 /* pretend it was %c with argument ch */
679 *buf = ch;
680 cp = buf;
681 size = 1;
682 sign = '\0';
683 break;
684 }
685
686 /*
687 * All reasonable formats wind up here. At this point, `cp'
688 * points to a string which (if not flags&LADJUST) should be
689 * padded out to `width' places. If flags&ZEROPAD, it should
690 * first be prefixed by any sign or other prefix; otherwise,
691 * it should be blank padded before the prefix is emitted.
692 * After any left-hand padding and prefixing, emit zeroes
693 * required by a decimal [diouxX] precision, then print the
694 * string proper, then emit zeroes required by any leftover
695 * floating precision; finally, if LADJUST, pad with blanks.
696 *
697 * Compute actual size, so we know how much to pad.
698 * size excludes decimal prec; realsz includes it.
699 */
700 realsz = dprec > size ? dprec : size;
701 if (sign)
702 realsz++;
703 else if (flags & HEXPREFIX)
704 realsz+= 2;
705
706 /* right-adjusting blank padding */
707 if ((flags & (LADJUST|ZEROPAD)) == 0)
708 PAD(width - realsz, blanks);
709
710 /* prefix */
711 if (sign) {
712 PRINT(&sign, 1);
713 } else if (flags & HEXPREFIX) {
714 ox[0] = '0';
715 ox[1] = ch;
716 PRINT(ox, 2);
717 }
718
719 /* right-adjusting zero padding */
720 if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD)
721 PAD(width - realsz, zeroes);
722
723 /* leading zeroes from decimal precision */
724 PAD(dprec - size, zeroes);
725
726 /* the string or number proper */
727 #ifdef FLOATING_POINT
728 if ((flags & FPT) == 0) {
729 PRINT(cp, size);
730 } else { /* glue together f_p fragments */
731 if (ch >= 'f') { /* 'f' or 'g' */
732 if (_double == 0) {
733 /* kludge for __dtoa irregularity */
734 PRINT("0", 1);
735 if (expt < ndig || (flags & ALT) != 0) {
736 PRINT(decimal_point, 1);
737 PAD(ndig - 1, zeroes);
738 }
739 } else if (expt <= 0) {
740 PRINT("0", 1);
741 PRINT(decimal_point, 1);
742 PAD(-expt, zeroes);
743 PRINT(cp, ndig);
744 } else if (expt >= ndig) {
745 PRINT(cp, ndig);
746 PAD(expt - ndig, zeroes);
747 if (flags & ALT)
748 PRINT(".", 1);
749 } else {
750 PRINT(cp, expt);
751 cp += expt;
752 PRINT(".", 1);
753 PRINT(cp, ndig-expt);
754 }
755 } else { /* 'e' or 'E' */
756 if (ndig > 1 || flags & ALT) {
757 ox[0] = *cp++;
758 ox[1] = '.';
759 PRINT(ox, 2);
760 if (_double) {
761 PRINT(cp, ndig-1);
762 } else /* 0.[0..] */
763 /* __dtoa irregularity */
764 PAD(ndig - 1, zeroes);
765 } else /* XeYYY */
766 PRINT(cp, 1);
767 PRINT(expstr, expsize);
768 }
769 }
770 #else
771 PRINT(cp, size);
772 #endif
773 /* left-adjusting padding (always blank) */
774 if (flags & LADJUST)
775 PAD(width - realsz, blanks);
776
777 /* finally, adjust ret */
778 ret += width > realsz ? width : realsz;
779
780 FLUSH(); /* copy out the I/O vectors */
781 }
782 done:
783 FLUSH();
784 error:
785 if (__sferror(fp))
786 ret = -1;
787 return (ret);
788 }
789
790 #ifdef FLOATING_POINT
791
792 static char *
793 cvt(value, ndigits, flags, sign, decpt, ch, length)
794 double value;
795 int ndigits, flags, *decpt, ch, *length;
796 char *sign;
797 {
798 int mode, dsgn;
799 char *digits, *bp, *rve;
800
801 _DIAGASSERT(decpt != NULL);
802 _DIAGASSERT(length != NULL);
803 _DIAGASSERT(sign != NULL);
804
805 if (ch == 'f') {
806 mode = 3; /* ndigits after the decimal point */
807 } else {
808 /* To obtain ndigits after the decimal point for the 'e'
809 * and 'E' formats, round to ndigits + 1 significant
810 * figures.
811 */
812 if (ch == 'e' || ch == 'E') {
813 ndigits++;
814 }
815 mode = 2; /* ndigits significant digits */
816 }
817
818 digits = __dtoa(value, mode, ndigits, decpt, &dsgn, &rve);
819 if (dsgn) {
820 value = -value;
821 *sign = '-';
822 } else
823 *sign = '\000';
824 if ((ch != 'g' && ch != 'G') || flags & ALT) { /* Print trailing zeros */
825 bp = digits + ndigits;
826 if (ch == 'f') {
827 if (*digits == '0' && value)
828 *decpt = -ndigits + 1;
829 bp += *decpt;
830 }
831 if (value == 0) /* kludge for __dtoa irregularity */
832 rve = bp;
833 while (rve < bp)
834 *rve++ = '0';
835 }
836 *length = rve - digits;
837 return (digits);
838 }
839
840 static int
841 exponent(p0, expon, fmtch)
842 char *p0;
843 int expon, fmtch;
844 {
845 char *p, *t;
846 char expbuf[MAXEXP];
847
848 _DIAGASSERT(p0 != NULL);
849
850 p = p0;
851 *p++ = fmtch;
852 if (expon < 0) {
853 expon = -expon;
854 *p++ = '-';
855 }
856 else
857 *p++ = '+';
858 t = expbuf + MAXEXP;
859 if (expon > 9) {
860 do {
861 *--t = to_char(expon % 10);
862 } while ((expon /= 10) > 9);
863 *--t = to_char(expon);
864 for (; t < expbuf + MAXEXP; *p++ = *t++);
865 }
866 else {
867 *p++ = '0';
868 *p++ = to_char(expon);
869 }
870 return (p - p0);
871 }
872 #endif /* FLOATING_POINT */
873