vfprintf.c revision 1.50 1 /* $NetBSD: vfprintf.c,v 1.50 2006/02/16 23:26:19 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 1.50 2006/02/16 23:26:19 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 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 #ifndef NO_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 /* FLOATING_POINT */
150
151 #define BUF 40
152
153 #endif /* NO_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 #ifndef NO_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 char *dtoaresult = NULL;
223 #endif
224
225 #ifdef __GNUC__ /* gcc has builtin quad type (long long) SOS */
226 #define quad_t long long
227 #define u_quad_t unsigned long long
228 #endif
229
230 #define INTMAX_T intmax_t
231 #define UINTMAX_T uintmax_t
232
233 UINTMAX_T _uintmax; /* integer arguments %[diouxX] */
234 enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */
235 int dprec; /* a copy of prec if [diouxX], 0 otherwise */
236 int realsz; /* field size expanded by dprec */
237 int size; /* size of converted field or string */
238 const char *xdigs = NULL;/* digits for [xX] conversion */
239 #define NIOV 8
240 struct __suio uio; /* output information: summary */
241 struct __siov iov[NIOV];/* ... and individual io vectors */
242 char buf[BUF]; /* space for %c, %[diouxX], %[eEfgG] */
243 char ox[2]; /* space for 0x hex-prefix */
244
245 /*
246 * Choose PADSIZE to trade efficiency vs. size. If larger printf
247 * fields occur frequently, increase PADSIZE and make the initialisers
248 * below longer.
249 */
250 #define PADSIZE 16 /* pad chunk size */
251 static const char blanks[PADSIZE] =
252 {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '};
253 static const char zeroes[PADSIZE] =
254 {'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'};
255
256 /*
257 * BEWARE, these `goto error' on error, and PAD uses `n'.
258 */
259 #define PRINT(ptr, len) { \
260 iovp->iov_base = __UNCONST(ptr); \
261 iovp->iov_len = (len); \
262 uio.uio_resid += (len); \
263 iovp++; \
264 if (++uio.uio_iovcnt >= NIOV) { \
265 if (__sprint(fp, &uio)) \
266 goto error; \
267 iovp = iov; \
268 } \
269 }
270 #define PAD(howmany, with) { \
271 if ((n = (howmany)) > 0) { \
272 while (n > PADSIZE) { \
273 PRINT(with, PADSIZE); \
274 n -= PADSIZE; \
275 } \
276 PRINT(with, n); \
277 } \
278 }
279 #define FLUSH() { \
280 if (uio.uio_resid && __sprint(fp, &uio)) \
281 goto error; \
282 uio.uio_iovcnt = 0; \
283 iovp = iov; \
284 }
285
286 /*
287 * To extend shorts properly, we need both signed and unsigned
288 * argument extraction methods.
289 */
290 #define SARG() \
291 (flags&MAXINT ? va_arg(ap, intmax_t) : \
292 flags&PTRINT ? va_arg(ap, ptrdiff_t) : \
293 flags&SIZEINT ? va_arg(ap, ssize_t) : /* XXX */ \
294 flags&QUADINT ? va_arg(ap, quad_t) : \
295 flags&LONGINT ? va_arg(ap, long) : \
296 flags&SHORTINT ? (long)(short)va_arg(ap, int) : \
297 (long)va_arg(ap, int))
298 #define UARG() \
299 (flags&MAXINT ? va_arg(ap, uintmax_t) : \
300 flags&PTRINT ? va_arg(ap, uintptr_t) : /* XXX */ \
301 flags&SIZEINT ? va_arg(ap, size_t) : \
302 flags&QUADINT ? va_arg(ap, u_quad_t) : \
303 flags&LONGINT ? va_arg(ap, u_long) : \
304 flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \
305 (u_long)va_arg(ap, u_int))
306
307 _DIAGASSERT(fp != NULL);
308 _DIAGASSERT(fmt0 != NULL);
309
310 _SET_ORIENTATION(fp, -1);
311
312 /* sorry, fprintf(read_only_file, "") returns -1, not 0 */
313 if (cantwrite(fp)) {
314 errno = EBADF;
315 return (-1);
316 }
317
318 /* optimise fprintf(stderr) (and other unbuffered Unix files) */
319 if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) &&
320 fp->_file >= 0) {
321 ret = __sbprintf(fp, fmt0, ap);
322 return (ret);
323 }
324
325 fmt = fmt0;
326 uio.uio_iov = iovp = iov;
327 uio.uio_resid = 0;
328 uio.uio_iovcnt = 0;
329 ret = 0;
330
331 memset(&ps, 0, sizeof(ps));
332
333 /*
334 * Scan the format for conversions (`%' character).
335 */
336 for (;;) {
337 cp = fmt;
338 while ((n = mbrtowc(&wc, fmt, MB_CUR_MAX, &ps)) > 0) {
339 fmt += n;
340 if (wc == '%') {
341 fmt--;
342 break;
343 }
344 }
345 if ((m = fmt - cp) != 0) {
346 PRINT(cp, m);
347 ret += m;
348 }
349 if (n <= 0)
350 goto done;
351 fmt++; /* skip over '%' */
352
353 flags = 0;
354 dprec = 0;
355 width = 0;
356 prec = -1;
357 sign = '\0';
358
359 rflag: ch = *fmt++;
360 reswitch: switch (ch) {
361 case ' ':
362 /*
363 * ``If the space and + flags both appear, the space
364 * flag will be ignored.''
365 * -- ANSI X3J11
366 */
367 if (!sign)
368 sign = ' ';
369 goto rflag;
370 case '#':
371 flags |= ALT;
372 goto rflag;
373 case '*':
374 /*
375 * ``A negative field width argument is taken as a
376 * - flag followed by a positive field width.''
377 * -- ANSI X3J11
378 * They don't exclude field widths read from args.
379 */
380 if ((width = va_arg(ap, int)) >= 0)
381 goto rflag;
382 width = -width;
383 /* FALLTHROUGH */
384 case '-':
385 flags |= LADJUST;
386 goto rflag;
387 case '+':
388 sign = '+';
389 goto rflag;
390 case '.':
391 if ((ch = *fmt++) == '*') {
392 n = va_arg(ap, int);
393 prec = n < 0 ? -1 : n;
394 goto rflag;
395 }
396 n = 0;
397 while (is_digit(ch)) {
398 n = 10 * n + to_digit(ch);
399 ch = *fmt++;
400 }
401 prec = n < 0 ? -1 : n;
402 goto reswitch;
403 case '0':
404 /*
405 * ``Note that 0 is taken as a flag, not as the
406 * beginning of a field width.''
407 * -- ANSI X3J11
408 */
409 flags |= ZEROPAD;
410 goto rflag;
411 case '1': case '2': case '3': case '4':
412 case '5': case '6': case '7': case '8': case '9':
413 n = 0;
414 do {
415 n = 10 * n + to_digit(ch);
416 ch = *fmt++;
417 } while (is_digit(ch));
418 width = n;
419 goto reswitch;
420 #ifndef NO_FLOATING_POINT
421 case 'L':
422 flags |= LONGDBL;
423 goto rflag;
424 #endif
425 case 'h':
426 flags |= SHORTINT;
427 goto rflag;
428 case 'j':
429 flags |= MAXINT;
430 goto rflag;
431 case 'l':
432 if (*fmt == 'l') {
433 fmt++;
434 flags |= QUADINT;
435 } else {
436 flags |= LONGINT;
437 }
438 goto rflag;
439 case 'q':
440 flags |= QUADINT;
441 goto rflag;
442 case 't':
443 flags |= PTRINT;
444 goto rflag;
445 case 'z':
446 flags |= SIZEINT;
447 goto rflag;
448 case 'c':
449 *buf = va_arg(ap, int);
450 cp = buf;
451 size = 1;
452 sign = '\0';
453 break;
454 case 'D':
455 flags |= LONGINT;
456 /*FALLTHROUGH*/
457 case 'd':
458 case 'i':
459 _uintmax = SARG();
460 if ((intmax_t)_uintmax < 0) {
461 _uintmax = -_uintmax;
462 sign = '-';
463 }
464 base = DEC;
465 goto number;
466 #ifndef NO_FLOATING_POINT
467 case 'e':
468 case 'E':
469 case 'f':
470 case 'F':
471 case 'g':
472 case 'G':
473 if (prec == -1) {
474 prec = DEFPREC;
475 } else if ((ch == 'g' || ch == 'G') && prec == 0) {
476 prec = 1;
477 }
478
479 if (flags & LONGDBL) {
480 _double = (double) va_arg(ap, long double);
481 } else {
482 _double = va_arg(ap, double);
483 }
484
485 /* do this before tricky precision changes */
486 if (isinf(_double)) {
487 if (_double < 0)
488 sign = '-';
489 if (ch == 'E' || ch == 'F' || ch == 'G')
490 cp = "INF";
491 else
492 cp = "inf";
493 size = 3;
494 break;
495 }
496 if (isnan(_double)) {
497 if (ch == 'E' || ch == 'F' || ch == 'G')
498 cp = "NAN";
499 else
500 cp = "nan";
501 size = 3;
502 break;
503 }
504
505 flags |= FPT;
506 if (dtoaresult)
507 __freedtoa(dtoaresult);
508 cp = dtoaresult = cvt(_double, prec, flags, &softsign,
509 &expt, ch, &ndig);
510 if (ch == 'g' || ch == 'G') {
511 if (expt <= -4 || expt > prec)
512 ch = (ch == 'g') ? 'e' : 'E';
513 else
514 ch = 'g';
515 }
516 if (ch == 'e' || ch == 'E') {
517 --expt;
518 expsize = exponent(expstr, expt, ch);
519 size = expsize + ndig;
520 if (ndig > 1 || flags & ALT)
521 ++size;
522 } else if (ch == 'f' || ch == 'F') {
523 if (expt > 0) {
524 size = expt;
525 if (prec || flags & ALT)
526 size += prec + 1;
527 } else /* "0.X" */
528 size = prec + 2;
529 } else if (expt >= ndig) { /* fixed g fmt */
530 size = expt;
531 if (flags & ALT)
532 ++size;
533 } else
534 size = ndig + (expt > 0 ?
535 1 : 2 - expt);
536
537 if (softsign)
538 sign = '-';
539 break;
540 #endif /* NO_FLOATING_POINT */
541 case 'n':
542 if (flags & MAXINT)
543 *va_arg(ap, intmax_t *) = ret;
544 else if (flags & PTRINT)
545 *va_arg(ap, ptrdiff_t *) = ret;
546 else if (flags & SIZEINT)
547 *va_arg(ap, ssize_t *) = ret; /* XXX */
548 else if (flags & QUADINT)
549 *va_arg(ap, quad_t *) = ret;
550 else if (flags & LONGINT)
551 *va_arg(ap, long *) = ret;
552 else if (flags & SHORTINT)
553 *va_arg(ap, short *) = ret;
554 else
555 *va_arg(ap, int *) = ret;
556 continue; /* no output */
557 case 'O':
558 flags |= LONGINT;
559 /*FALLTHROUGH*/
560 case 'o':
561 _uintmax = UARG();
562 base = OCT;
563 goto nosign;
564 case 'p':
565 /*
566 * ``The argument shall be a pointer to void. The
567 * value of the pointer is converted to a sequence
568 * of printable characters, in an implementation-
569 * defined manner.''
570 * -- ANSI X3J11
571 */
572 /* NOSTRICT */
573 _uintmax = (u_long)va_arg(ap, void *);
574 base = HEX;
575 xdigs = "0123456789abcdef";
576 flags |= HEXPREFIX;
577 ch = 'x';
578 goto nosign;
579 case 's':
580 if ((cp = va_arg(ap, char *)) == NULL)
581 cp = "(null)";
582 if (prec >= 0) {
583 /*
584 * can't use strlen; can only look for the
585 * NUL in the first `prec' characters, and
586 * strlen() will go further.
587 */
588 char *p = memchr(cp, 0, (size_t)prec);
589
590 if (p != NULL) {
591 size = p - cp;
592 if (size > prec)
593 size = prec;
594 } else
595 size = prec;
596 } else
597 size = strlen(cp);
598 sign = '\0';
599 break;
600 case 'U':
601 flags |= LONGINT;
602 /*FALLTHROUGH*/
603 case 'u':
604 _uintmax = UARG();
605 base = DEC;
606 goto nosign;
607 case 'X':
608 xdigs = "0123456789ABCDEF";
609 goto hex;
610 case 'x':
611 xdigs = "0123456789abcdef";
612 hex: _uintmax = UARG();
613 base = HEX;
614 /* leading 0x/X only if non-zero */
615 if (flags & ALT && _uintmax != 0)
616 flags |= HEXPREFIX;
617
618 /* unsigned conversions */
619 nosign: sign = '\0';
620 /*
621 * ``... diouXx conversions ... if a precision is
622 * specified, the 0 flag will be ignored.''
623 * -- ANSI X3J11
624 */
625 number: if ((dprec = prec) >= 0)
626 flags &= ~ZEROPAD;
627
628 /*
629 * ``The result of converting a zero value with an
630 * explicit precision of zero is no characters.''
631 * -- ANSI X3J11
632 */
633 bp = buf + BUF;
634 if (_uintmax != 0 || prec != 0) {
635 /*
636 * Unsigned mod is hard, and unsigned mod
637 * by a constant is easier than that by
638 * a variable; hence this switch.
639 */
640 switch (base) {
641 case OCT:
642 do {
643 *--bp = to_char(_uintmax & 7);
644 _uintmax >>= 3;
645 } while (_uintmax);
646 /* handle octal leading 0 */
647 if (flags & ALT && *bp != '0')
648 *--bp = '0';
649 break;
650
651 case DEC:
652 /* many numbers are 1 digit */
653 while (_uintmax >= 10) {
654 *--bp = to_char(_uintmax % 10);
655 _uintmax /= 10;
656 }
657 *--bp = to_char(_uintmax);
658 break;
659
660 case HEX:
661 do {
662 *--bp = xdigs[(size_t)
663 (_uintmax & 15)];
664 _uintmax >>= 4;
665 } while (_uintmax);
666 break;
667
668 default:
669 cp = "bug in vfprintf: bad base";
670 size = strlen(cp);
671 goto skipsize;
672 }
673 }
674 cp = bp;
675 size = buf + BUF - bp;
676 skipsize:
677 break;
678 default: /* "%?" prints ?, unless ? is NUL */
679 if (ch == '\0')
680 goto done;
681 /* pretend it was %c with argument ch */
682 *buf = ch;
683 cp = buf;
684 size = 1;
685 sign = '\0';
686 break;
687 }
688
689 /*
690 * All reasonable formats wind up here. At this point, `cp'
691 * points to a string which (if not flags&LADJUST) should be
692 * padded out to `width' places. If flags&ZEROPAD, it should
693 * first be prefixed by any sign or other prefix; otherwise,
694 * it should be blank padded before the prefix is emitted.
695 * After any left-hand padding and prefixing, emit zeroes
696 * required by a decimal [diouxX] precision, then print the
697 * string proper, then emit zeroes required by any leftover
698 * floating precision; finally, if LADJUST, pad with blanks.
699 *
700 * Compute actual size, so we know how much to pad.
701 * size excludes decimal prec; realsz includes it.
702 */
703 realsz = dprec > size ? dprec : size;
704 if (sign)
705 realsz++;
706 else if (flags & HEXPREFIX)
707 realsz+= 2;
708
709 /* right-adjusting blank padding */
710 if ((flags & (LADJUST|ZEROPAD)) == 0)
711 PAD(width - realsz, blanks);
712
713 /* prefix */
714 if (sign) {
715 PRINT(&sign, 1);
716 } else if (flags & HEXPREFIX) {
717 ox[0] = '0';
718 ox[1] = ch;
719 PRINT(ox, 2);
720 }
721
722 /* right-adjusting zero padding */
723 if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD)
724 PAD(width - realsz, zeroes);
725
726 /* leading zeroes from decimal precision */
727 PAD(dprec - size, zeroes);
728
729 /* the string or number proper */
730 #ifndef NO_FLOATING_POINT
731 if ((flags & FPT) == 0) {
732 PRINT(cp, size);
733 } else { /* glue together f_p fragments */
734 if (ch >= 'f') { /* 'f' or 'g' */
735 if (_double == 0) {
736 /* kludge for __dtoa irregularity */
737 PRINT("0", 1);
738 if (expt < ndig || (flags & ALT) != 0) {
739 PRINT(decimal_point, 1);
740 PAD(ndig - 1, zeroes);
741 }
742 } else if (expt <= 0) {
743 PRINT("0", 1);
744 PRINT(decimal_point, 1);
745 PAD(-expt, zeroes);
746 PRINT(cp, ndig);
747 } else if (expt >= ndig) {
748 PRINT(cp, ndig);
749 PAD(expt - ndig, zeroes);
750 if (flags & ALT)
751 PRINT(".", 1);
752 } else {
753 PRINT(cp, expt);
754 cp += expt;
755 PRINT(".", 1);
756 PRINT(cp, ndig-expt);
757 }
758 } else { /* 'e' or 'E' */
759 if (ndig > 1 || flags & ALT) {
760 ox[0] = *cp++;
761 ox[1] = '.';
762 PRINT(ox, 2);
763 if (_double) {
764 PRINT(cp, ndig-1);
765 } else /* 0.[0..] */
766 /* __dtoa irregularity */
767 PAD(ndig - 1, zeroes);
768 } else /* XeYYY */
769 PRINT(cp, 1);
770 PRINT(expstr, expsize);
771 }
772 }
773 #else
774 PRINT(cp, size);
775 #endif
776 /* left-adjusting padding (always blank) */
777 if (flags & LADJUST)
778 PAD(width - realsz, blanks);
779
780 /* finally, adjust ret */
781 ret += width > realsz ? width : realsz;
782
783 FLUSH(); /* copy out the I/O vectors */
784 }
785 done:
786 FLUSH();
787 error:
788 #ifndef NO_FLOATING_POINT
789 if (dtoaresult)
790 __freedtoa(dtoaresult);
791 #endif
792 if (__sferror(fp))
793 ret = -1;
794 return (ret);
795 }
796
797 #ifndef NO_FLOATING_POINT
798
799 static char *
800 cvt(value, ndigits, flags, sign, decpt, ch, length)
801 double value;
802 int ndigits, flags, *decpt, ch, *length;
803 char *sign;
804 {
805 int mode, dsgn;
806 char *digits, *bp, *rve;
807
808 _DIAGASSERT(decpt != NULL);
809 _DIAGASSERT(length != NULL);
810 _DIAGASSERT(sign != NULL);
811
812 if (ch == 'f') {
813 mode = 3; /* ndigits after the decimal point */
814 } else {
815 /* To obtain ndigits after the decimal point for the 'e'
816 * and 'E' formats, round to ndigits + 1 significant
817 * figures.
818 */
819 if (ch == 'e' || ch == 'E') {
820 ndigits++;
821 }
822 mode = 2; /* ndigits significant digits */
823 }
824
825 digits = __dtoa(value, mode, ndigits, decpt, &dsgn, &rve);
826 if (dsgn) {
827 value = -value;
828 *sign = '-';
829 } else
830 *sign = '\000';
831 if ((ch != 'g' && ch != 'G') || flags & ALT) { /* Print trailing zeros */
832 bp = digits + ndigits;
833 if (ch == 'f') {
834 if (*digits == '0' && value)
835 *decpt = -ndigits + 1;
836 bp += *decpt;
837 }
838 if (value == 0) /* kludge for __dtoa irregularity */
839 rve = bp;
840 while (rve < bp)
841 *rve++ = '0';
842 }
843 *length = rve - digits;
844 return (digits);
845 }
846
847 static int
848 exponent(p0, expon, fmtch)
849 char *p0;
850 int expon, fmtch;
851 {
852 char *p, *t;
853 char expbuf[MAXEXP];
854
855 _DIAGASSERT(p0 != NULL);
856
857 p = p0;
858 *p++ = fmtch;
859 if (expon < 0) {
860 expon = -expon;
861 *p++ = '-';
862 }
863 else
864 *p++ = '+';
865 t = expbuf + MAXEXP;
866 if (expon > 9) {
867 do {
868 *--t = to_char(expon % 10);
869 } while ((expon /= 10) > 9);
870 *--t = to_char(expon);
871 for (; t < expbuf + MAXEXP; *p++ = *t++);
872 }
873 else {
874 *p++ = '0';
875 *p++ = to_char(expon);
876 }
877 return (p - p0);
878 }
879 #endif /* NO_FLOATING_POINT */
880