summaryrefslogtreecommitdiff
path: root/src/lib9/fmt/fltfmt.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/lib9/fmt/fltfmt.c')
-rw-r--r--src/lib9/fmt/fltfmt.c679
1 files changed, 0 insertions, 679 deletions
diff --git a/src/lib9/fmt/fltfmt.c b/src/lib9/fmt/fltfmt.c
deleted file mode 100644
index 9f3f3edab..000000000
--- a/src/lib9/fmt/fltfmt.c
+++ /dev/null
@@ -1,679 +0,0 @@
-/*
- * The authors of this software are Rob Pike and Ken Thompson,
- * with contributions from Mike Burrows and Sean Dorward.
- *
- * Copyright (c) 2002-2006 by Lucent Technologies.
- * Portions Copyright (c) 2004 Google Inc.
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose without fee is hereby granted, provided that this entire notice
- * is included in all copies of any software which is or includes a copy
- * or modification of this software and in all copies of the supporting
- * documentation for such software.
- * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
- * WARRANTY. IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES
- * NOR GOOGLE INC MAKE ANY REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING
- * THE MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
- */
-
-/* Copyright (c) 2002-2006 Lucent Technologies; see LICENSE */
-#include <u.h>
-#include <errno.h>
-#include <libc.h>
-#include "fmtdef.h"
-
-enum
-{
- FDIGIT = 30,
- FDEFLT = 6,
- NSIGNIF = 17
-};
-
-/*
- * first few powers of 10, enough for about 1/2 of the
- * total space for doubles.
- */
-static double pows10[] =
-{
- 1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
- 1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
- 1e20, 1e21, 1e22, 1e23, 1e24, 1e25, 1e26, 1e27, 1e28, 1e29,
- 1e30, 1e31, 1e32, 1e33, 1e34, 1e35, 1e36, 1e37, 1e38, 1e39,
- 1e40, 1e41, 1e42, 1e43, 1e44, 1e45, 1e46, 1e47, 1e48, 1e49,
- 1e50, 1e51, 1e52, 1e53, 1e54, 1e55, 1e56, 1e57, 1e58, 1e59,
- 1e60, 1e61, 1e62, 1e63, 1e64, 1e65, 1e66, 1e67, 1e68, 1e69,
- 1e70, 1e71, 1e72, 1e73, 1e74, 1e75, 1e76, 1e77, 1e78, 1e79,
- 1e80, 1e81, 1e82, 1e83, 1e84, 1e85, 1e86, 1e87, 1e88, 1e89,
- 1e90, 1e91, 1e92, 1e93, 1e94, 1e95, 1e96, 1e97, 1e98, 1e99,
- 1e100, 1e101, 1e102, 1e103, 1e104, 1e105, 1e106, 1e107, 1e108, 1e109,
- 1e110, 1e111, 1e112, 1e113, 1e114, 1e115, 1e116, 1e117, 1e118, 1e119,
- 1e120, 1e121, 1e122, 1e123, 1e124, 1e125, 1e126, 1e127, 1e128, 1e129,
- 1e130, 1e131, 1e132, 1e133, 1e134, 1e135, 1e136, 1e137, 1e138, 1e139,
- 1e140, 1e141, 1e142, 1e143, 1e144, 1e145, 1e146, 1e147, 1e148, 1e149,
- 1e150, 1e151, 1e152, 1e153, 1e154, 1e155, 1e156, 1e157, 1e158, 1e159,
-};
-
-#undef pow10
-#define npows10 ((int)(sizeof(pows10)/sizeof(pows10[0])))
-#define pow10(x) fmtpow10(x)
-
-static double
-pow10(int n)
-{
- double d;
- int neg;
-
- neg = 0;
- if(n < 0){
- neg = 1;
- n = -n;
- }
-
- if(n < npows10)
- d = pows10[n];
- else{
- d = pows10[npows10-1];
- for(;;){
- n -= npows10 - 1;
- if(n < npows10){
- d *= pows10[n];
- break;
- }
- d *= pows10[npows10 - 1];
- }
- }
- if(neg)
- return 1./d;
- return d;
-}
-
-/*
- * add 1 to the decimal integer string a of length n.
- * if 99999 overflows into 10000, return 1 to tell caller
- * to move the virtual decimal point.
- */
-static int
-xadd1(char *a, int n)
-{
- char *b;
- int c;
-
- if(n < 0 || n > NSIGNIF)
- return 0;
- for(b = a+n-1; b >= a; b--) {
- c = *b + 1;
- if(c <= '9') {
- *b = c;
- return 0;
- }
- *b = '0';
- }
- /*
- * need to overflow adding digit.
- * shift number down and insert 1 at beginning.
- * decimal is known to be 0s or we wouldn't
- * have gotten this far. (e.g., 99999+1 => 00000)
- */
- a[0] = '1';
- return 1;
-}
-
-/*
- * subtract 1 from the decimal integer string a.
- * if 10000 underflows into 09999, make it 99999
- * and return 1 to tell caller to move the virtual
- * decimal point. this way, xsub1 is inverse of xadd1.
- */
-static int
-xsub1(char *a, int n)
-{
- char *b;
- int c;
-
- if(n < 0 || n > NSIGNIF)
- return 0;
- for(b = a+n-1; b >= a; b--) {
- c = *b - 1;
- if(c >= '0') {
- if(c == '0' && b == a) {
- /*
- * just zeroed the top digit; shift everyone up.
- * decimal is known to be 9s or we wouldn't
- * have gotten this far. (e.g., 10000-1 => 09999)
- */
- *b = '9';
- return 1;
- }
- *b = c;
- return 0;
- }
- *b = '9';
- }
- /*
- * can't get here. the number a is always normalized
- * so that it has a nonzero first digit.
- */
- abort();
-}
-
-/*
- * format exponent like sprintf(p, "e%+02d", e)
- */
-static void
-xfmtexp(char *p, int e, int ucase)
-{
- char se[9];
- int i;
-
- *p++ = ucase ? 'E' : 'e';
- if(e < 0) {
- *p++ = '-';
- e = -e;
- } else
- *p++ = '+';
- i = 0;
- while(e) {
- se[i++] = e % 10 + '0';
- e /= 10;
- }
- while(i < 2)
- se[i++] = '0';
- while(i > 0)
- *p++ = se[--i];
- *p++ = '\0';
-}
-
-/*
- * compute decimal integer m, exp such that:
- * f = m*10^exp
- * m is as short as possible with losing exactness
- * assumes special cases (NaN, +Inf, -Inf) have been handled.
- */
-static void
-xdtoa(double f, char *s, int *exp, int *neg, int *ns)
-{
- int c, d, e2, e, ee, i, ndigit, oerrno;
- char tmp[NSIGNIF+10];
- double g;
-
- oerrno = errno; /* in case strtod smashes errno */
-
- /*
- * make f non-negative.
- */
- *neg = 0;
- if(f < 0) {
- f = -f;
- *neg = 1;
- }
-
- /*
- * must handle zero specially.
- */
- if(f == 0){
- *exp = 0;
- s[0] = '0';
- s[1] = '\0';
- *ns = 1;
- return;
- }
-
- /*
- * find g,e such that f = g*10^e.
- * guess 10-exponent using 2-exponent, then fine tune.
- */
- frexp(f, &e2);
- e = (int)(e2 * .301029995664);
- g = f * pow10(-e);
- while(g < 1) {
- e--;
- g = f * pow10(-e);
- }
- while(g >= 10) {
- e++;
- g = f * pow10(-e);
- }
-
- /*
- * convert NSIGNIF digits as a first approximation.
- */
- for(i=0; i<NSIGNIF; i++) {
- d = (int)g;
- s[i] = d+'0';
- g = (g-d) * 10;
- }
- s[i] = 0;
-
- /*
- * adjust e because s is 314159... not 3.14159...
- */
- e -= NSIGNIF-1;
- xfmtexp(s+NSIGNIF, e, 0);
-
- /*
- * adjust conversion until strtod(s) == f exactly.
- */
- for(i=0; i<10; i++) {
- g = strtod(s, nil);
- if(f > g) {
- if(xadd1(s, NSIGNIF)) {
- /* gained a digit */
- e--;
- xfmtexp(s+NSIGNIF, e, 0);
- }
- continue;
- }
- if(f < g) {
- if(xsub1(s, NSIGNIF)) {
- /* lost a digit */
- e++;
- xfmtexp(s+NSIGNIF, e, 0);
- }
- continue;
- }
- break;
- }
-
- /*
- * play with the decimal to try to simplify.
- */
-
- /*
- * bump last few digits up to 9 if we can
- */
- for(i=NSIGNIF-1; i>=NSIGNIF-3; i--) {
- c = s[i];
- if(c != '9') {
- s[i] = '9';
- g = strtod(s, nil);
- if(g != f) {
- s[i] = c;
- break;
- }
- }
- }
-
- /*
- * add 1 in hopes of turning 9s to 0s
- */
- if(s[NSIGNIF-1] == '9') {
- strcpy(tmp, s);
- ee = e;
- if(xadd1(tmp, NSIGNIF)) {
- ee--;
- xfmtexp(tmp+NSIGNIF, ee, 0);
- }
- g = strtod(tmp, nil);
- if(g == f) {
- strcpy(s, tmp);
- e = ee;
- }
- }
-
- /*
- * bump last few digits down to 0 as we can.
- */
- for(i=NSIGNIF-1; i>=NSIGNIF-3; i--) {
- c = s[i];
- if(c != '0') {
- s[i] = '0';
- g = strtod(s, nil);
- if(g != f) {
- s[i] = c;
- break;
- }
- }
- }
-
- /*
- * remove trailing zeros.
- */
- ndigit = NSIGNIF;
- while(ndigit > 1 && s[ndigit-1] == '0'){
- e++;
- --ndigit;
- }
- s[ndigit] = 0;
- *exp = e;
- *ns = ndigit;
- errno = oerrno;
-}
-
-#ifdef PLAN9PORT
-static char *special[] = { "NaN", "NaN", "+Inf", "+Inf", "-Inf", "-Inf" };
-#else
-static char *special[] = { "nan", "NAN", "inf", "INF", "-inf", "-INF" };
-#endif
-
-int
-__efgfmt(Fmt *fmt)
-{
- char buf[NSIGNIF+10], *dot, *digits, *p, *s, suf[10], *t;
- double f;
- int c, chr, dotwid, e, exp, fl, ndigits, neg, newndigits;
- int pad, point, prec, realchr, sign, sufwid, ucase, wid, z1, z2;
- Rune r, *rs, *rt;
-
- if(fmt->flags&FmtLong)
- f = va_arg(fmt->args, long double);
- else
- f = va_arg(fmt->args, double);
-
- /*
- * extract formatting flags
- */
- fl = fmt->flags;
- fmt->flags = 0;
- prec = FDEFLT;
- if(fl & FmtPrec)
- prec = fmt->prec;
- chr = fmt->r;
- ucase = 0;
- switch(chr) {
- case 'A':
- case 'E':
- case 'F':
- case 'G':
- chr += 'a'-'A';
- ucase = 1;
- break;
- }
-
- /*
- * pick off special numbers.
- */
- if(__isNaN(f)) {
- s = special[0+ucase];
- special:
- fmt->flags = fl & (FmtWidth|FmtLeft);
- return __fmtcpy(fmt, s, strlen(s), strlen(s));
- }
- if(__isInf(f, 1)) {
- s = special[2+ucase];
- goto special;
- }
- if(__isInf(f, -1)) {
- s = special[4+ucase];
- goto special;
- }
-
- /*
- * get exact representation.
- */
- digits = buf;
- xdtoa(f, digits, &exp, &neg, &ndigits);
-
- /*
- * get locale's decimal point.
- */
- dot = fmt->decimal;
- if(dot == nil)
- dot = ".";
- dotwid = utflen(dot);
-
- /*
- * now the formatting fun begins.
- * compute parameters for actual fmt:
- *
- * pad: number of spaces to insert before/after field.
- * z1: number of zeros to insert before digits
- * z2: number of zeros to insert after digits
- * point: number of digits to print before decimal point
- * ndigits: number of digits to use from digits[]
- * suf: trailing suffix, like "e-5"
- */
- realchr = chr;
- switch(chr){
- case 'g':
- /*
- * convert to at most prec significant digits. (prec=0 means 1)
- */
- if(prec == 0)
- prec = 1;
- if(ndigits > prec) {
- if(digits[prec] >= '5' && xadd1(digits, prec))
- exp++;
- exp += ndigits-prec;
- ndigits = prec;
- }
-
- /*
- * extra rules for %g (implemented below):
- * trailing zeros removed after decimal unless FmtSharp.
- * decimal point only if digit follows.
- */
-
- /* fall through to %e */
- default:
- case 'e':
- /*
- * one significant digit before decimal, no leading zeros.
- */
- point = 1;
- z1 = 0;
-
- /*
- * decimal point is after ndigits digits right now.
- * slide to be after first.
- */
- e = exp + (ndigits-1);
-
- /*
- * if this is %g, check exponent and convert prec
- */
- if(realchr == 'g') {
- if(-4 <= e && e < prec)
- goto casef;
- prec--; /* one digit before decimal; rest after */
- }
-
- /*
- * compute trailing zero padding or truncate digits.
- */
- if(1+prec >= ndigits)
- z2 = 1+prec - ndigits;
- else {
- /*
- * truncate digits
- */
- assert(realchr != 'g');
- newndigits = 1+prec;
- if(digits[newndigits] >= '5' && xadd1(digits, newndigits)) {
- /*
- * had 999e4, now have 100e5
- */
- e++;
- }
- ndigits = newndigits;
- z2 = 0;
- }
- xfmtexp(suf, e, ucase);
- sufwid = strlen(suf);
- break;
-
- casef:
- case 'f':
- /*
- * determine where digits go with respect to decimal point
- */
- if(ndigits+exp > 0) {
- point = ndigits+exp;
- z1 = 0;
- } else {
- point = 1;
- z1 = 1 + -(ndigits+exp);
- }
-
- /*
- * %g specifies prec = number of significant digits
- * convert to number of digits after decimal point
- */
- if(realchr == 'g')
- prec += z1 - point;
-
- /*
- * compute trailing zero padding or truncate digits.
- */
- if(point+prec >= z1+ndigits)
- z2 = point+prec - (z1+ndigits);
- else {
- /*
- * truncate digits
- */
- assert(realchr != 'g');
- newndigits = point+prec - z1;
- if(newndigits < 0) {
- z1 += newndigits;
- newndigits = 0;
- } else if(newndigits == 0) {
- /* perhaps round up */
- if(digits[0] >= '5'){
- digits[0] = '1';
- newndigits = 1;
- goto newdigit;
- }
- } else if(digits[newndigits] >= '5' && xadd1(digits, newndigits)) {
- /*
- * digits was 999, is now 100; make it 1000
- */
- digits[newndigits++] = '0';
- newdigit:
- /*
- * account for new digit
- */
- if(z1) /* 0.099 => 0.100 or 0.99 => 1.00*/
- z1--;
- else /* 9.99 => 10.00 */
- point++;
- }
- z2 = 0;
- ndigits = newndigits;
- }
- sufwid = 0;
- break;
- }
-
- /*
- * if %g is given without FmtSharp, remove trailing zeros.
- * must do after truncation, so that e.g. print %.3g 1.001
- * produces 1, not 1.00. sorry, but them's the rules.
- */
- if(realchr == 'g' && !(fl & FmtSharp)) {
- if(z1+ndigits+z2 >= point) {
- if(z1+ndigits < point)
- z2 = point - (z1+ndigits);
- else{
- z2 = 0;
- while(z1+ndigits > point && digits[ndigits-1] == '0')
- ndigits--;
- }
- }
- }
-
- /*
- * compute width of all digits and decimal point and suffix if any
- */
- wid = z1+ndigits+z2;
- if(wid > point)
- wid += dotwid;
- else if(wid == point){
- if(fl & FmtSharp)
- wid += dotwid;
- else
- point++; /* do not print any decimal point */
- }
- wid += sufwid;
-
- /*
- * determine sign
- */
- sign = 0;
- if(neg)
- sign = '-';
- else if(fl & FmtSign)
- sign = '+';
- else if(fl & FmtSpace)
- sign = ' ';
- if(sign)
- wid++;
-
- /*
- * compute padding
- */
- pad = 0;
- if((fl & FmtWidth) && fmt->width > wid)
- pad = fmt->width - wid;
- if(pad && !(fl & FmtLeft) && (fl & FmtZero)){
- z1 += pad;
- point += pad;
- pad = 0;
- }
-
- /*
- * format the actual field. too bad about doing this twice.
- */
- if(fmt->runes){
- if(pad && !(fl & FmtLeft) && __rfmtpad(fmt, pad) < 0)
- return -1;
- rt = (Rune*)fmt->to;
- rs = (Rune*)fmt->stop;
- if(sign)
- FMTRCHAR(fmt, rt, rs, sign);
- while(z1>0 || ndigits>0 || z2>0) {
- if(z1 > 0){
- z1--;
- c = '0';
- }else if(ndigits > 0){
- ndigits--;
- c = *digits++;
- }else{
- z2--;
- c = '0';
- }
- FMTRCHAR(fmt, rt, rs, c);
- if(--point == 0) {
- for(p = dot; *p; ){
- p += chartorune(&r, p);
- FMTRCHAR(fmt, rt, rs, r);
- }
- }
- }
- fmt->nfmt += rt - (Rune*)fmt->to;
- fmt->to = rt;
- if(sufwid && __fmtcpy(fmt, suf, sufwid, sufwid) < 0)
- return -1;
- if(pad && (fl & FmtLeft) && __rfmtpad(fmt, pad) < 0)
- return -1;
- }else{
- if(pad && !(fl & FmtLeft) && __fmtpad(fmt, pad) < 0)
- return -1;
- t = (char*)fmt->to;
- s = (char*)fmt->stop;
- if(sign)
- FMTCHAR(fmt, t, s, sign);
- while(z1>0 || ndigits>0 || z2>0) {
- if(z1 > 0){
- z1--;
- c = '0';
- }else if(ndigits > 0){
- ndigits--;
- c = *digits++;
- }else{
- z2--;
- c = '0';
- }
- FMTCHAR(fmt, t, s, c);
- if(--point == 0)
- for(p=dot; *p; p++)
- FMTCHAR(fmt, t, s, *p);
- }
- fmt->nfmt += t - (char*)fmt->to;
- fmt->to = t;
- if(sufwid && __fmtcpy(fmt, suf, sufwid, sufwid) < 0)
- return -1;
- if(pad && (fl & FmtLeft) && __fmtpad(fmt, pad) < 0)
- return -1;
- }
- return 0;
-}
-
generated by cgit v1.2.3 (git 2.39.1) at 2025-06-05 04:30:25 +0000