/* * Copyright (c) 1990 Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms are permitted * provided that the above copyright notice and this paragraph are * duplicated in all such forms and that any documentation, * advertising materials, and other materials related to such * distribution and use acknowledge that the software was developed * by the University of California, Berkeley. The name of the * University may not be used to endorse or promote products derived * from this software without specific prior written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. */ #if defined(LIBC_SCCS) && !defined(lint) static char sccsid[] = "%W% (Berkeley) %G%"; #endif /* LIBC_SCCS and not lint */ /* * Actual printf innards. * * This code is large and complicated... */ #include #include "ioprivate.h" #include #include /* * Define FLOATING_POINT to get floating point. */ #ifndef NO_FLOATING_POINT #define FLOATING_POINT #endif /* end of configuration stuff */ /* * Helper class and function for `fprintf to unbuffered': creates a * temporary buffer. We only work on write-only files; this avoids * worries about ungetc buffers and so forth. */ class help_streambuf : public backupbuf { public: char *buffer; int buf_size; streambuf *sb; help_streambuf(streambuf *sbuf, char *buf, int n) { sb = sbuf; buffer = buf; buf_size = n; setp(buffer, buffer+buf_size); } ~help_streambuf(); virtual int overflow(int c = EOF); }; int help_streambuf::overflow(int c) { int used = pptr() - pbase(); if (used) { sb->sputn(pbase(), used); pbump(-used); } if (c == EOF || buf_size == 0) return sb->overflow(c); return sputc(c); } help_streambuf::~help_streambuf() { int used = pptr() - pbase(); if (used) { sb->sputn(pbase(), used); pbump(-used); } } int help_vform(streambuf *sb, char const *fmt0, va_list ap) { char buf[_G_BUFSIZ]; help_streambuf helper(sb, buf, _G_BUFSIZ); return helper.vform(fmt0, ap); } #ifdef FLOATING_POINT #include "floatio.h" #define BUF (MAXEXP+MAXFRACT+1) /* + decimal point */ #define DEFPREC 6 extern "C" double modf(double, double*); #else /* no FLOATING_POINT */ #define BUF 40 #endif /* FLOATING_POINT */ /* * Macros for converting digits to letters and vice versa */ #define to_digit(c) ((c) - '0') #define is_digit(c) ((unsigned)to_digit(c) <= 9) #define to_char(n) ((n) + '0') /* * Flags used during conversion. */ #define LONGINT 0x01 /* long integer */ #define LONGDBL 0x02 /* long double; unimplemented */ #define SHORTINT 0x04 /* short integer */ #define ALT 0x08 /* alternate form */ #define LADJUST 0x10 /* left adjustment */ #define ZEROPAD 0x20 /* zero (as opposed to blank) pad */ #define HEXPREFIX 0x40 /* add 0x or 0X prefix */ int streambuf::vform(char const *fmt0, _G_va_list ap) { register const char *fmt; /* format string */ register int ch; /* character from fmt */ register int n; /* handy integer (short term usage) */ register char *cp; /* handy char pointer (short term usage) */ const char *fmark; /* for remembering a place in fmt */ register int flags; /* flags as above */ int ret; /* return value accumulator */ int width; /* width from format (%8d), or 0 */ int prec; /* precision from format (%.3d), or -1 */ char sign; /* sign prefix (' ', '+', '-', or \0) */ #ifdef FLOATING_POINT int softsign; /* temporary negative sign for floats */ double _double; /* double precision arguments %[eEfgG] */ #ifndef USE_DTOA int fpprec; /* `extra' floating precision in [eEfgG] */ #endif #endif unsigned long _ulong; /* integer arguments %[diouxX] */ enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */ int dprec; /* a copy of prec if [diouxX], 0 otherwise */ int dpad; /* extra 0 padding needed for integers */ int fieldsz; /* field size expanded by sign, dpad etc */ // The initialization of 'size' is to suppress a warning that // 'size' might be used unitialized. It seems gcc can't // quite grok this spaghetti code ... int size = 0; /* size of converted field or string */ char buf[BUF]; /* space for %c, %[diouxX], %[eEfgG] */ char ox[2]; /* space for 0x hex-prefix */ /* * Choose PADSIZE to trade efficiency vs size. If larger * printf fields occur frequently, increase PADSIZE (and make * the initialisers below longer). */ #define PADSIZE 16 /* pad chunk size */ static char const blanks[PADSIZE] = {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '}; static char const zeroes[PADSIZE] = {'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'}; /* * BEWARE, these `goto error' on error, and PAD uses `n'. */ #define PRINT(ptr, len) \ do { if (sputn(ptr, len) != len) goto error; } while (0) #if 1 #define PAD_SP(howmany) if (padn(' ', howmany) < 0) goto error; #define PAD_0(howmany) if (padn('0', howmany) < 0) goto error; #else #define PAD(howmany, with) { \ if ((n = (howmany)) > 0) { \ while (n > PADSIZE) { \ PRINT(with, PADSIZE); \ n -= PADSIZE; \ } \ PRINT(with, n); \ } \ } #define PAD_SP(howmany) PAD(howmany, blanks) #define PAD_0(howmany) PAD(howmany, zeroes) #endif /* * To extend shorts properly, we need both signed and unsigned * argument extraction methods. */ #define SARG() \ (flags&LONGINT ? va_arg(ap, long) : \ flags&SHORTINT ? (long)(short)va_arg(ap, int) : \ (long)va_arg(ap, int)) #define UARG() \ (flags&LONGINT ? va_arg(ap, unsigned long) : \ flags&SHORTINT ? (unsigned long)(unsigned short)va_arg(ap, int) : \ (unsigned long)va_arg(ap, unsigned int)) /* optimise cerr (and other unbuffered Unix files) */ if (unbuffered()) return help_vform(this, fmt0, ap); fmt = fmt0; ret = 0; /* * Scan the format for conversions (`%' character). */ for (;;) { for (fmark = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++) /* void */; if ((n = fmt - fmark) != 0) { PRINT(fmark, n); ret += n; } if (ch == '\0') goto done; fmt++; /* skip over '%' */ flags = 0; dprec = 0; #if defined(FLOATING_POINT) && !defined (USE_DTOA) fpprec = 0; #endif width = 0; prec = -1; sign = '\0'; rflag: ch = *fmt++; reswitch: switch (ch) { case ' ': /* * ``If the space and + flags both appear, the space * flag will be ignored.'' * -- ANSI X3J11 */ if (!sign) sign = ' '; goto rflag; case '#': flags |= ALT; goto rflag; case '*': /* * ``A negative field width argument is taken as a * - flag followed by a positive field width.'' * -- ANSI X3J11 * They don't exclude field widths read from args. */ if ((width = va_arg(ap, int)) >= 0) goto rflag; width = -width; /* FALLTHROUGH */ case '-': flags |= LADJUST; flags &= ~ZEROPAD; /* '-' disables '0' */ goto rflag; case '+': sign = '+'; goto rflag; case '.': if ((ch = *fmt++) == '*') { n = va_arg(ap, int); prec = n < 0 ? -1 : n; goto rflag; } n = 0; while (is_digit(ch)) { n = 10 * n + to_digit(ch); ch = *fmt++; } prec = n < 0 ? -1 : n; goto reswitch; case '0': /* * ``Note that 0 is taken as a flag, not as the * beginning of a field width.'' * -- ANSI X3J11 */ if (!(flags & LADJUST)) flags |= ZEROPAD; /* '-' disables '0' */ goto rflag; case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': n = 0; do { n = 10 * n + to_digit(ch); ch = *fmt++; } while (is_digit(ch)); width = n; goto reswitch; #ifdef FLOATING_POINT case 'L': flags |= LONGDBL; goto rflag; #endif case 'h': flags |= SHORTINT; goto rflag; case 'l': flags |= LONGINT; goto rflag; case 'c': *(cp = buf) = va_arg(ap, int); size = 1; sign = '\0'; break; case 'D': flags |= LONGINT; /*FALLTHROUGH*/ case 'd': case 'i': _ulong = SARG(); if ((long)_ulong < 0) { _ulong = -_ulong; sign = '-'; } base = DEC; goto number; #ifdef FLOATING_POINT case 'e': case 'E': case 'f': case 'F': case 'g': case 'G': _double = va_arg(ap, double); #ifdef USE_DTOA { ios::fmtflags fmt_flags = 0; int fill = ' '; if (flags & ALT) fmt_flags |= ios::showpoint; if (flags & LADJUST) fmt_flags |= ios::left; else if (flags & ZEROPAD) fmt_flags |= ios::internal, fill = '0'; n = __outfloat(_double, this, ch, width, prec < 0 ? DEFPREC : prec, fmt_flags, sign, fill); if (n < 0) goto error; ret += n; } // CHECK ERROR! continue; #else /* * don't do unrealistic precision; just pad it with * zeroes later, so buffer size stays rational. */ if (prec > MAXFRACT) { if ((ch != 'g' && ch != 'G') || (flags&ALT)) fpprec = prec - MAXFRACT; prec = MAXFRACT; } else if (prec == -1) prec = DEFPREC; // __cvt_double may have to round up before the // "start" of its buffer, i.e. // ``intf("%.2f", (double)9.999);''; // if the first character is still NUL, it did. // softsign avoids negative 0 if _double < 0 but // no significant digits will be shown. cp = buf; *cp = '\0'; size = __cvt_double(_double, prec, flags, &softsign, ch, cp, buf + sizeof(buf)); if (softsign) sign = '-'; if (*cp == '\0') cp++; break; #endif #endif /* FLOATING_POINT */ case 'n': if (flags & LONGINT) *va_arg(ap, long *) = ret; else if (flags & SHORTINT) *va_arg(ap, short *) = ret; else *va_arg(ap, int *) = ret; continue; /* no output */ case 'O': flags |= LONGINT; /*FALLTHROUGH*/ case 'o': _ulong = UARG(); base = OCT; goto nosign; case 'p': /* * ``The argument shall be a pointer to void. The * value of the pointer is converted to a sequence * of printable characters, in an implementation- * defined manner.'' * -- ANSI X3J11 */ /* NOSTRICT */ _ulong = (unsigned long)va_arg(ap, void *); base = HEX; flags |= HEXPREFIX; ch = 'x'; goto nosign; case 's': if ((cp = va_arg(ap, char *)) == NULL) cp = "(null)"; if (prec >= 0) { /* * can't use strlen; can only look for the * NUL in the first `prec' characters, and * strlen() will go further. */ char *p = (char*)memchr(cp, 0, prec); if (p != NULL) { size = p - cp; if (size > prec) size = prec; } else size = prec; } else size = strlen(cp); sign = '\0'; break; case 'U': flags |= LONGINT; /*FALLTHROUGH*/ case 'u': _ulong = UARG(); base = DEC; goto nosign; case 'X': case 'x': _ulong = UARG(); base = HEX; /* leading 0x/X only if non-zero */ if (flags & ALT && _ulong != 0) flags |= HEXPREFIX; /* unsigned conversions */ nosign: sign = '\0'; /* * ``... diouXx conversions ... if a precision is * specified, the 0 flag will be ignored.'' * -- ANSI X3J11 */ number: if ((dprec = prec) >= 0) flags &= ~ZEROPAD; /* * ``The result of converting a zero value with an * explicit precision of zero is no characters.'' * -- ANSI X3J11 */ cp = buf + BUF; if (_ulong != 0 || prec != 0) { char *xdigs; /* digits for [xX] conversion */ /* * unsigned mod is hard, and unsigned mod * by a constant is easier than that by * a variable; hence this switch. */ switch (base) { case OCT: do { *--cp = to_char(_ulong & 7); _ulong >>= 3; } while (_ulong); /* handle octal leading 0 */ if (flags & ALT && *cp != '0') *--cp = '0'; break; case DEC: /* many numbers are 1 digit */ while (_ulong >= 10) { *--cp = to_char(_ulong % 10); _ulong /= 10; } *--cp = to_char(_ulong); break; case HEX: if (ch == 'X') xdigs = "0123456789ABCDEF"; else /* ch == 'x' || ch == 'p' */ xdigs = "0123456789abcdef"; do { *--cp = xdigs[_ulong & 15]; _ulong >>= 4; } while (_ulong); break; default: cp = "bug in vform: bad base"; goto skipsize; } } size = buf + BUF - cp; skipsize: break; default: /* "%?" prints ?, unless ? is NUL */ if (ch == '\0') goto done; /* pretend it was %c with argument ch */ cp = buf; *cp = ch; size = 1; sign = '\0'; break; } /* * All reasonable formats wind up here. At this point, * `cp' points to a string which (if not flags&LADJUST) * should be padded out to `width' places. If * flags&ZEROPAD, it should first be prefixed by any * sign or other prefix; otherwise, it should be blank * padded before the prefix is emitted. After any * left-hand padding and prefixing, emit zeroes * required by a decimal [diouxX] precision, then print * the string proper, then emit zeroes required by any * leftover floating precision; finally, if LADJUST, * pad with blanks. */ /* * compute actual size, so we know how much to pad. */ #if defined(FLOATING_POINT) && !defined (USE_DTOA) fieldsz = size + fpprec; #else fieldsz = size; #endif dpad = dprec - size; if (dpad < 0) dpad = 0; if (sign) fieldsz++; else if (flags & HEXPREFIX) fieldsz += 2; fieldsz += dpad; /* right-adjusting blank padding */ if ((flags & (LADJUST|ZEROPAD)) == 0) PAD_SP(width - fieldsz); /* prefix */ if (sign) { PRINT(&sign, 1); } else if (flags & HEXPREFIX) { ox[0] = '0'; ox[1] = ch; PRINT(ox, 2); } /* right-adjusting zero padding */ if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) PAD_0(width - fieldsz); /* leading zeroes from decimal precision */ PAD_0(dpad); /* the string or number proper */ PRINT(cp, size); #if defined(FLOATING_POINT) && !defined (USE_DTOA) /* trailing f.p. zeroes */ PAD_0(fpprec); #endif /* left-adjusting padding (always blank) */ if (flags & LADJUST) PAD_SP(width - fieldsz); /* finally, adjust ret */ ret += width > fieldsz ? width : fieldsz; } done: return ret; error: return EOF; /* NOTREACHED */ } #if defined(FLOATING_POINT) && !defined(USE_DTOA) static char *exponent(register char *p, register int exp, int fmtch) { register char *t; char expbuf[MAXEXP]; *p++ = fmtch; if (exp < 0) { exp = -exp; *p++ = '-'; } else *p++ = '+'; t = expbuf + MAXEXP; if (exp > 9) { do { *--t = to_char(exp % 10); } while ((exp /= 10) > 9); *--t = to_char(exp); for (; t < expbuf + MAXEXP; *p++ = *t++); } else { *p++ = '0'; *p++ = to_char(exp); } return (p); } static char * round(double fract, int *exp, register char *start, register char *end, char ch, int *signp) { double tmp; if (fract) (void)modf(fract * 10, &tmp); else tmp = to_digit(ch); if (tmp > 4) for (;; --end) { if (*end == '.') --end; if (++*end <= '9') break; *end = '0'; if (end == start) { if (exp) { /* e/E; increment exponent */ *end = '1'; ++*exp; } else { /* f; add extra digit */ *--end = '1'; --start; } break; } } /* ``"%.3f", (double)-0.0004'' gives you a negative 0. */ else if (*signp == '-') for (;; --end) { if (*end == '.') --end; if (*end != '0') break; if (end == start) *signp = 0; } return (start); } int __cvt_double(double number, register int prec, int flags, int *signp, int fmtch, char *startp, char *endp) { register char *p, *t; register double fract; int dotrim = 0, expcnt, gformat = 0; double integer, tmp; expcnt = 0; if (number < 0) { number = -number; *signp = '-'; } else *signp = 0; fract = modf(number, &integer); /* get an extra slot for rounding. */ t = ++startp; /* * get integer portion of number; put into the end of the buffer; the * .01 is added for modf(356.0 / 10, &integer) returning .59999999... */ for (p = endp - 1; integer; ++expcnt) { tmp = modf(integer / 10, &integer); *p-- = to_char((int)((tmp + .01) * 10)); } switch (fmtch) { case 'f': case 'F': /* reverse integer into beginning of buffer */ if (expcnt) for (; ++p < endp; *t++ = *p); else *t++ = '0'; /* * if precision required or alternate flag set, add in a * decimal point. */ if (prec || flags&ALT) *t++ = '.'; /* if requires more precision and some fraction left */ if (fract) { if (prec) do { fract = modf(fract * 10, &tmp); *t++ = to_char((int)tmp); } while (--prec && fract); if (fract) startp = round(fract, (int *)NULL, startp, t - 1, (char)0, signp); } for (; prec--; *t++ = '0'); break; case 'e': case 'E': eformat: if (expcnt) { *t++ = *++p; if (prec || flags&ALT) *t++ = '.'; /* if requires more precision and some integer left */ for (; prec && ++p < endp; --prec) *t++ = *p; /* * if done precision and more of the integer component, * round using it; adjust fract so we don't re-round * later. */ if (!prec && ++p < endp) { fract = 0; startp = round((double)0, &expcnt, startp, t - 1, *p, signp); } /* adjust expcnt for digit in front of decimal */ --expcnt; } /* until first fractional digit, decrement exponent */ else if (fract) { /* adjust expcnt for digit in front of decimal */ for (expcnt = -1;; --expcnt) { fract = modf(fract * 10, &tmp); if (tmp) break; } *t++ = to_char((int)tmp); if (prec || flags&ALT) *t++ = '.'; } else { *t++ = '0'; if (prec || flags&ALT) *t++ = '.'; } /* if requires more precision and some fraction left */ if (fract) { if (prec) do { fract = modf(fract * 10, &tmp); *t++ = to_char((int)tmp); } while (--prec && fract); if (fract) startp = round(fract, &expcnt, startp, t - 1, (char)0, signp); } /* if requires more precision */ for (; prec--; *t++ = '0'); /* unless alternate flag, trim any g/G format trailing 0's */ if (gformat && !(flags&ALT)) { while (t > startp && *--t == '0'); if (*t == '.') --t; ++t; } t = exponent(t, expcnt, fmtch); break; case 'g': case 'G': /* a precision of 0 is treated as a precision of 1. */ if (!prec) ++prec; /* * ``The style used depends on the value converted; style e * will be used only if the exponent resulting from the * conversion is less than -4 or greater than the precision.'' * -- ANSI X3J11 */ if (expcnt > prec || (!expcnt && fract && fract < .0001)) { /* * g/G format counts "significant digits, not digits of * precision; for the e/E format, this just causes an * off-by-one problem, i.e. g/G considers the digit * before the decimal point significant and e/E doesn't * count it as precision. */ --prec; fmtch -= 2; /* G->E, g->e */ gformat = 1; goto eformat; } /* * reverse integer into beginning of buffer, * note, decrement precision */ if (expcnt) for (; ++p < endp; *t++ = *p, --prec); else *t++ = '0'; /* * if precision required or alternate flag set, add in a * decimal point. If no digits yet, add in leading 0. */ if (prec || flags&ALT) { dotrim = 1; *t++ = '.'; } else dotrim = 0; /* if requires more precision and some fraction left */ if (fract) { if (prec) { /* If no integer part, don't count initial * zeros as significant digits. */ do { fract = modf(fract * 10, &tmp); *t++ = to_char((int)tmp); } while(!tmp && !expcnt); while (--prec && fract) { fract = modf(fract * 10, &tmp); *t++ = to_char((int)tmp); } } if (fract) startp = round(fract, (int *)NULL, startp, t - 1, (char)0, signp); } /* alternate format, adds 0's for precision, else trim 0's */ if (flags&ALT) for (; prec--; *t++ = '0'); else if (dotrim) { while (t > startp && *--t == '0'); if (*t != '.') ++t; } } return (t - startp); } #endif /* defined(FLOATING_POINT) && !defined(USE_DTOA) */ int streambuf::form(char const *format ...) { va_list ap; va_start(ap, format); int count = vform(format, ap); va_end(ap); return count; }