comparison gsm-fw/sprintf/old/doprnt.c.43tahoe @ 145:7e45ada9c365

gsm-fw: sprintf overhaul in preparation for adding %f format support
author Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
date Thu, 14 Nov 2013 17:51:33 +0000
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144:ea819b60fe0d 145:7e45ada9c365
1 /*
2 * Copyright (c) 1988 Regents of the University of California.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms are permitted
6 * provided that the above copyright notice and this paragraph are
7 * duplicated in all such forms and that any documentation,
8 * advertising materials, and other materials related to such
9 * distribution and use acknowledge that the software was developed
10 * by the University of California, Berkeley. The name of the
11 * University may not be used to endorse or promote products derived
12 * from this software without specific prior written permission.
13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16 */
17
18 #if defined(LIBC_SCCS) && !defined(lint)
19 static char sccsid[] = "@(#)doprnt.c 5.35 (Berkeley) 6/27/88";
20 #endif /* LIBC_SCCS and not lint */
21
22 #include <sys/types.h>
23 #include <varargs.h>
24 #include <stdio.h>
25 #include <ctype.h>
26
27 /* 11-bit exponent (VAX G floating point) is 308 decimal digits */
28 #define MAXEXP 308
29 /* 128 bit fraction takes up 39 decimal digits; max reasonable precision */
30 #define MAXFRACT 39
31
32 #define DEFPREC 6
33
34 #define BUF (MAXEXP+MAXFRACT+1) /* + decimal point */
35
36 #define PUTC(ch) (void) putc(ch, fp)
37
38 #define ARG() \
39 _ulong = flags&LONGINT ? va_arg(argp, long) : \
40 flags&SHORTINT ? va_arg(argp, short) : va_arg(argp, int);
41
42 #define todigit(c) ((c) - '0')
43 #define tochar(n) ((n) + '0')
44
45 /* have to deal with the negative buffer count kludge */
46 #define NEGATIVE_COUNT_KLUDGE
47
48 #define LONGINT 0x01 /* long integer */
49 #define LONGDBL 0x02 /* long double; unimplemented */
50 #define SHORTINT 0x04 /* short integer */
51 #define ALT 0x08 /* alternate form */
52 #define LADJUST 0x10 /* left adjustment */
53 #define ZEROPAD 0x20 /* zero (as opposed to blank) pad */
54 #define HEXPREFIX 0x40 /* add 0x or 0X prefix */
55
56 _doprnt(fmt0, argp, fp)
57 u_char *fmt0;
58 va_list argp;
59 register FILE *fp;
60 {
61 register u_char *fmt; /* format string */
62 register int ch; /* character from fmt */
63 register int cnt; /* return value accumulator */
64 register int n; /* random handy integer */
65 register char *t; /* buffer pointer */
66 double _double; /* double precision arguments %[eEfgG] */
67 u_long _ulong; /* integer arguments %[diouxX] */
68 int base; /* base for [diouxX] conversion */
69 int dprec; /* decimal precision in [diouxX] */
70 int fieldsz; /* field size expanded by sign, etc */
71 int flags; /* flags as above */
72 int fpprec; /* `extra' floating precision in [eEfgG] */
73 int prec; /* precision from format (%.3d), or -1 */
74 int realsz; /* field size expanded by decimal precision */
75 int size; /* size of converted field or string */
76 int width; /* width from format (%8d), or 0 */
77 char sign; /* sign prefix (' ', '+', '-', or \0) */
78 char softsign; /* temporary negative sign for floats */
79 char *digs; /* digits for [diouxX] conversion */
80 char buf[BUF]; /* space for %c, %[diouxX], %[eEfgG] */
81
82 if (fp->_flag & _IORW) {
83 fp->_flag |= _IOWRT;
84 fp->_flag &= ~(_IOEOF|_IOREAD);
85 }
86 if ((fp->_flag & _IOWRT) == 0)
87 return (EOF);
88
89 fmt = fmt0;
90 digs = "0123456789abcdef";
91 for (cnt = 0;; ++fmt) {
92 n = fp->_cnt;
93 for (t = (char *)fp->_ptr; (ch = *fmt) && ch != '%';
94 ++cnt, ++fmt)
95 if (--n < 0
96 #ifdef NEGATIVE_COUNT_KLUDGE
97 && (!(fp->_flag & _IOLBF) || -n >= fp->_bufsiz)
98 #endif
99 || ch == '\n' && fp->_flag & _IOLBF) {
100 fp->_cnt = n;
101 fp->_ptr = t;
102 (void) _flsbuf((u_char)ch, fp);
103 n = fp->_cnt;
104 t = (char *)fp->_ptr;
105 } else
106 *t++ = ch;
107 fp->_cnt = n;
108 fp->_ptr = t;
109 if (!ch)
110 return (cnt);
111
112 flags = 0; dprec = 0; fpprec = 0; width = 0;
113 prec = -1;
114 sign = '\0';
115
116 rflag: switch (*++fmt) {
117 case ' ':
118 /*
119 * ``If the space and + flags both appear, the space
120 * flag will be ignored.''
121 * -- ANSI X3J11
122 */
123 if (!sign)
124 sign = ' ';
125 goto rflag;
126 case '#':
127 flags |= ALT;
128 goto rflag;
129 case '*':
130 /*
131 * ``A negative field width argument is taken as a
132 * - flag followed by a positive field width.''
133 * -- ANSI X3J11
134 * They don't exclude field widths read from args.
135 */
136 if ((width = va_arg(argp, int)) >= 0)
137 goto rflag;
138 width = -width;
139 /* FALLTHROUGH */
140 case '-':
141 flags |= LADJUST;
142 goto rflag;
143 case '+':
144 sign = '+';
145 goto rflag;
146 case '.':
147 if (*++fmt == '*')
148 n = va_arg(argp, int);
149 else {
150 n = 0;
151 while (isascii(*fmt) && isdigit(*fmt))
152 n = 10 * n + todigit(*fmt++);
153 --fmt;
154 }
155 prec = n < 0 ? -1 : n;
156 goto rflag;
157 case '0':
158 /*
159 * ``Note that 0 is taken as a flag, not as the
160 * beginning of a field width.''
161 * -- ANSI X3J11
162 */
163 flags |= ZEROPAD;
164 goto rflag;
165 case '1': case '2': case '3': case '4':
166 case '5': case '6': case '7': case '8': case '9':
167 n = 0;
168 do {
169 n = 10 * n + todigit(*fmt);
170 } while (isascii(*++fmt) && isdigit(*fmt));
171 width = n;
172 --fmt;
173 goto rflag;
174 case 'L':
175 flags |= LONGDBL;
176 goto rflag;
177 case 'h':
178 flags |= SHORTINT;
179 goto rflag;
180 case 'l':
181 flags |= LONGINT;
182 goto rflag;
183 case 'c':
184 *(t = buf) = va_arg(argp, int);
185 size = 1;
186 sign = '\0';
187 goto pforw;
188 case 'D':
189 flags |= LONGINT;
190 /*FALLTHROUGH*/
191 case 'd':
192 case 'i':
193 ARG();
194 if ((long)_ulong < 0) {
195 _ulong = -_ulong;
196 sign = '-';
197 }
198 base = 10;
199 goto number;
200 case 'e':
201 case 'E':
202 case 'f':
203 case 'g':
204 case 'G':
205 _double = va_arg(argp, double);
206 /*
207 * don't do unrealistic precision; just pad it with
208 * zeroes later, so buffer size stays rational.
209 */
210 if (prec > MAXFRACT) {
211 if (*fmt != 'g' && *fmt != 'G' || (flags&ALT))
212 fpprec = prec - MAXFRACT;
213 prec = MAXFRACT;
214 }
215 else if (prec == -1)
216 prec = DEFPREC;
217 /*
218 * softsign avoids negative 0 if _double is < 0 and
219 * no significant digits will be shown
220 */
221 if (_double < 0) {
222 softsign = '-';
223 _double = -_double;
224 }
225 else
226 softsign = 0;
227 /*
228 * cvt may have to round up past the "start" of the
229 * buffer, i.e. ``intf("%.2f", (double)9.999);'';
230 * if the first char isn't NULL, it did.
231 */
232 *buf = NULL;
233 size = cvt(_double, prec, flags, &softsign, *fmt, buf,
234 buf + sizeof(buf));
235 if (softsign)
236 sign = '-';
237 t = *buf ? buf : buf + 1;
238 goto pforw;
239 case 'n':
240 if (flags & LONGINT)
241 *va_arg(argp, long *) = cnt;
242 else if (flags & SHORTINT)
243 *va_arg(argp, short *) = cnt;
244 else
245 *va_arg(argp, int *) = cnt;
246 break;
247 case 'O':
248 flags |= LONGINT;
249 /*FALLTHROUGH*/
250 case 'o':
251 ARG();
252 base = 8;
253 goto nosign;
254 case 'p':
255 /*
256 * ``The argument shall be a pointer to void. The
257 * value of the pointer is converted to a sequence
258 * of printable characters, in an implementation-
259 * defined manner.''
260 * -- ANSI X3J11
261 */
262 /* NOSTRICT */
263 _ulong = (u_long)va_arg(argp, void *);
264 base = 16;
265 goto nosign;
266 case 's':
267 if (!(t = va_arg(argp, char *)))
268 t = "(null)";
269 if (prec >= 0) {
270 /*
271 * can't use strlen; can only look for the
272 * NUL in the first `prec' characters, and
273 * strlen() will go further.
274 */
275 char *p, *memchr();
276
277 if (p = memchr(t, 0, prec)) {
278 size = p - t;
279 if (size > prec)
280 size = prec;
281 } else
282 size = prec;
283 } else
284 size = strlen(t);
285 sign = '\0';
286 goto pforw;
287 case 'U':
288 flags |= LONGINT;
289 /*FALLTHROUGH*/
290 case 'u':
291 ARG();
292 base = 10;
293 goto nosign;
294 case 'X':
295 digs = "0123456789ABCDEF";
296 /* FALLTHROUGH */
297 case 'x':
298 ARG();
299 base = 16;
300 /* leading 0x/X only if non-zero */
301 if (flags & ALT && _ulong != 0)
302 flags |= HEXPREFIX;
303
304 /* unsigned conversions */
305 nosign: sign = '\0';
306 /*
307 * ``... diouXx conversions ... if a precision is
308 * specified, the 0 flag will be ignored.''
309 * -- ANSI X3J11
310 */
311 number: if ((dprec = prec) >= 0)
312 flags &= ~ZEROPAD;
313
314 /*
315 * ``The result of converting a zero value with an
316 * explicit precision of zero is no characters.''
317 * -- ANSI X3J11
318 */
319 t = buf + BUF;
320 if (_ulong != 0 || prec != 0) {
321 do {
322 *--t = digs[_ulong % base];
323 _ulong /= base;
324 } while (_ulong);
325 digs = "0123456789abcdef";
326 if (flags & ALT && base == 8 && *t != '0')
327 *--t = '0'; /* octal leading 0 */
328 }
329 size = buf + BUF - t;
330
331 pforw:
332 /*
333 * All reasonable formats wind up here. At this point,
334 * `t' points to a string which (if not flags&LADJUST)
335 * should be padded out to `width' places. If
336 * flags&ZEROPAD, it should first be prefixed by any
337 * sign or other prefix; otherwise, it should be blank
338 * padded before the prefix is emitted. After any
339 * left-hand padding and prefixing, emit zeroes
340 * required by a decimal [diouxX] precision, then print
341 * the string proper, then emit zeroes required by any
342 * leftover floating precision; finally, if LADJUST,
343 * pad with blanks.
344 */
345
346 /*
347 * compute actual size, so we know how much to pad
348 * fieldsz excludes decimal prec; realsz includes it
349 */
350 fieldsz = size + fpprec;
351 if (sign)
352 fieldsz++;
353 if (flags & HEXPREFIX)
354 fieldsz += 2;
355 realsz = dprec > fieldsz ? dprec : fieldsz;
356
357 /* right-adjusting blank padding */
358 if ((flags & (LADJUST|ZEROPAD)) == 0 && width)
359 for (n = realsz; n < width; n++)
360 PUTC(' ');
361 /* prefix */
362 if (sign)
363 PUTC(sign);
364 if (flags & HEXPREFIX) {
365 PUTC('0');
366 PUTC((char)*fmt);
367 }
368 /* right-adjusting zero padding */
369 if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD)
370 for (n = realsz; n < width; n++)
371 PUTC('0');
372 /* leading zeroes from decimal precision */
373 for (n = fieldsz; n < dprec; n++)
374 PUTC('0');
375
376 /* the string or number proper */
377 if (fp->_cnt - (n = size) >= 0 &&
378 (fp->_flag & _IOLBF) == 0) {
379 fp->_cnt -= n;
380 bcopy(t, (char *)fp->_ptr, n);
381 fp->_ptr += n;
382 } else
383 while (--n >= 0)
384 PUTC(*t++);
385 /* trailing f.p. zeroes */
386 while (--fpprec >= 0)
387 PUTC('0');
388 /* left-adjusting padding (always blank) */
389 if (flags & LADJUST)
390 for (n = realsz; n < width; n++)
391 PUTC(' ');
392 /* finally, adjust cnt */
393 cnt += width > realsz ? width : realsz;
394 break;
395 case '\0': /* "%?" prints ?, unless ? is NULL */
396 return (cnt);
397 default:
398 PUTC((char)*fmt);
399 cnt++;
400 }
401 }
402 /* NOTREACHED */
403 }
404
405 static
406 cvt(number, prec, flags, signp, fmtch, startp, endp)
407 double number;
408 register int prec;
409 int flags;
410 u_char fmtch;
411 char *signp, *startp, *endp;
412 {
413 register char *p, *t;
414 register double fract;
415 int dotrim, expcnt, gformat;
416 double integer, tmp, modf();
417 char *exponent(), *round();
418
419 dotrim = expcnt = gformat = 0;
420 fract = modf(number, &integer);
421
422 /* get an extra slot for rounding. */
423 t = ++startp;
424
425 /*
426 * get integer portion of number; put into the end of the buffer; the
427 * .01 is added for modf(356.0 / 10, &integer) returning .59999999...
428 */
429 for (p = endp - 1; integer; ++expcnt) {
430 tmp = modf(integer / 10, &integer);
431 *p-- = tochar((int)((tmp + .01) * 10));
432 }
433 switch(fmtch) {
434 case 'f':
435 /* reverse integer into beginning of buffer */
436 if (expcnt)
437 for (; ++p < endp; *t++ = *p);
438 else
439 *t++ = '0';
440 /*
441 * if precision required or alternate flag set, add in a
442 * decimal point.
443 */
444 if (prec || flags&ALT)
445 *t++ = '.';
446 /* if requires more precision and some fraction left */
447 if (fract) {
448 if (prec)
449 do {
450 fract = modf(fract * 10, &tmp);
451 *t++ = tochar((int)tmp);
452 } while (--prec && fract);
453 if (fract)
454 startp = round(fract, (int *)NULL, startp,
455 t - 1, (char)0, signp);
456 }
457 for (; prec--; *t++ = '0');
458 break;
459 case 'e':
460 case 'E':
461 eformat: if (expcnt) {
462 *t++ = *++p;
463 if (prec || flags&ALT)
464 *t++ = '.';
465 /* if requires more precision and some integer left */
466 for (; prec && ++p < endp; --prec)
467 *t++ = *p;
468 /*
469 * if done precision and more of the integer component,
470 * round using it; adjust fract so we don't re-round
471 * later.
472 */
473 if (!prec && ++p < endp) {
474 fract = 0;
475 startp = round((double)0, &expcnt, startp,
476 t - 1, *p, signp);
477 }
478 /* adjust expcnt for digit in front of decimal */
479 --expcnt;
480 }
481 /* until first fractional digit, decrement exponent */
482 else if (fract) {
483 /* adjust expcnt for digit in front of decimal */
484 for (expcnt = -1;; --expcnt) {
485 fract = modf(fract * 10, &tmp);
486 if (tmp)
487 break;
488 }
489 *t++ = tochar((int)tmp);
490 if (prec || flags&ALT)
491 *t++ = '.';
492 }
493 else {
494 *t++ = '0';
495 if (prec || flags&ALT)
496 *t++ = '.';
497 }
498 /* if requires more precision and some fraction left */
499 if (fract) {
500 if (prec)
501 do {
502 fract = modf(fract * 10, &tmp);
503 *t++ = tochar((int)tmp);
504 } while (--prec && fract);
505 if (fract)
506 startp = round(fract, &expcnt, startp,
507 t - 1, (char)0, signp);
508 }
509 /* if requires more precision */
510 for (; prec--; *t++ = '0');
511
512 /* unless alternate flag, trim any g/G format trailing 0's */
513 if (gformat && !(flags&ALT)) {
514 while (t > startp && *--t == '0');
515 if (*t == '.')
516 --t;
517 ++t;
518 }
519 t = exponent(t, expcnt, fmtch);
520 break;
521 case 'g':
522 case 'G':
523 /* a precision of 0 is treated as a precision of 1. */
524 if (!prec)
525 ++prec;
526 /*
527 * ``The style used depends on the value converted; style e
528 * will be used only if the exponent resulting from the
529 * conversion is less than -4 or greater than the precision.''
530 * -- ANSI X3J11
531 */
532 if (expcnt > prec || !expcnt && fract && fract < .0001) {
533 /*
534 * g/G format counts "significant digits, not digits of
535 * precision; for the e/E format, this just causes an
536 * off-by-one problem, i.e. g/G considers the digit
537 * before the decimal point significant and e/E doesn't
538 * count it as precision.
539 */
540 --prec;
541 fmtch -= 2; /* G->E, g->e */
542 gformat = 1;
543 goto eformat;
544 }
545 /*
546 * reverse integer into beginning of buffer,
547 * note, decrement precision
548 */
549 if (expcnt)
550 for (; ++p < endp; *t++ = *p, --prec);
551 else
552 *t++ = '0';
553 /*
554 * if precision required or alternate flag set, add in a
555 * decimal point. If no digits yet, add in leading 0.
556 */
557 if (prec || flags&ALT) {
558 dotrim = 1;
559 *t++ = '.';
560 }
561 else
562 dotrim = 0;
563 /* if requires more precision and some fraction left */
564 if (fract) {
565 if (prec) {
566 do {
567 fract = modf(fract * 10, &tmp);
568 *t++ = tochar((int)tmp);
569 } while(!tmp);
570 while (--prec && fract) {
571 fract = modf(fract * 10, &tmp);
572 *t++ = tochar((int)tmp);
573 }
574 }
575 if (fract)
576 startp = round(fract, (int *)NULL, startp,
577 t - 1, (char)0, signp);
578 }
579 /* alternate format, adds 0's for precision, else trim 0's */
580 if (flags&ALT)
581 for (; prec--; *t++ = '0');
582 else if (dotrim) {
583 while (t > startp && *--t == '0');
584 if (*t != '.')
585 ++t;
586 }
587 }
588 return(t - startp);
589 }
590
591 static char *
592 round(fract, exp, start, end, ch, signp)
593 double fract;
594 int *exp;
595 register char *start, *end;
596 char ch, *signp;
597 {
598 double tmp;
599
600 if (fract)
601 (void)modf(fract * 10, &tmp);
602 else
603 tmp = todigit(ch);
604 if (tmp > 4)
605 for (;; --end) {
606 if (*end == '.')
607 --end;
608 if (++*end <= '9')
609 break;
610 *end = '0';
611 if (end == start) {
612 if (exp) { /* e/E; increment exponent */
613 *end = '1';
614 ++*exp;
615 }
616 else { /* f; add extra digit */
617 *--end = '1';
618 --start;
619 }
620 break;
621 }
622 }
623 /* ``"%.3f", (double)-0.0004'' gives you a negative 0. */
624 else if (*signp == '-')
625 for (;; --end) {
626 if (*end == '.')
627 --end;
628 if (*end != '0')
629 break;
630 if (end == start)
631 *signp = 0;
632 }
633 return(start);
634 }
635
636 static char *
637 exponent(p, exp, fmtch)
638 register char *p;
639 register int exp;
640 u_char fmtch;
641 {
642 register char *t;
643 char expbuf[MAXEXP];
644
645 *p++ = fmtch;
646 if (exp < 0) {
647 exp = -exp;
648 *p++ = '-';
649 }
650 else
651 *p++ = '+';
652 t = expbuf + MAXEXP;
653 if (exp > 9) {
654 do {
655 *--t = tochar(exp % 10);
656 } while ((exp /= 10) > 9);
657 *--t = tochar(exp);
658 for (; t < expbuf + MAXEXP; *p++ = *t++);
659 }
660 else {
661 *p++ = '0';
662 *p++ = tochar(exp);
663 }
664 return(p);
665 }