FreeCalypso > hg > freecalypso-tools
view target-utils/libprintf/doprnt.c @ 768:4e6837859c0b
target-utils: simregs.h moved to include directory
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Thu, 11 Mar 2021 23:34:54 +0000 |
parents | e7502631a0f9 |
children |
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/* the guts of printf - this implementation came from 4.3BSD-Tahoe */ #include <sys/types.h> #include <ctype.h> #include <stdarg.h> #define PUTC(ch) ((*outfunc)((ch), outfunc_param)) #define ARG() \ _ulong = flags&LONGINT ? va_arg(argp, long) : va_arg(argp, int); #define BUF 12 #define todigit(c) ((c) - '0') #define tochar(n) ((n) + '0') #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 */ _doprnt(fmt0, argp, outfunc, outfunc_param) u_char *fmt0; va_list argp; void (*outfunc)(); void *outfunc_param; { register u_char *fmt; /* format string */ register int ch; /* character from fmt */ register int cnt; /* return value accumulator */ register int n; /* random handy integer */ register char *t; /* buffer pointer */ u_long _ulong; /* integer arguments %[diouxX] */ int base; /* base for [diouxX] conversion */ int dprec; /* decimal precision in [diouxX] */ int fieldsz; /* field size expanded by sign, etc */ int flags; /* flags as above */ int prec; /* precision from format (%.3d), or -1 */ int realsz; /* field size expanded by decimal precision */ int size; /* size of converted field or string */ int width; /* width from format (%8d), or 0 */ char sign; /* sign prefix (' ', '+', '-', or \0) */ char softsign; /* temporary negative sign for floats */ char *digs; /* digits for [diouxX] conversion */ char buf[BUF]; /* space for %c, %[diouxX], %[eEfgG] */ fmt = fmt0; digs = "0123456789abcdef"; for (cnt = 0;; ++fmt) { for (; (ch = *fmt) && ch != '%'; ++cnt, ++fmt) PUTC(ch); if (!ch) return (cnt); flags = 0; dprec = 0; width = 0; prec = -1; sign = '\0'; rflag: switch (*++fmt) { 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(argp, int)) >= 0) goto rflag; width = -width; /* FALLTHROUGH */ case '-': flags |= LADJUST; goto rflag; case '+': sign = '+'; goto rflag; case '.': if (*++fmt == '*') n = va_arg(argp, int); else { n = 0; while (isascii(*fmt) && isdigit(*fmt)) n = 10 * n + todigit(*fmt++); --fmt; } prec = n < 0 ? -1 : n; goto rflag; case '0': /* * ``Note that 0 is taken as a flag, not as the * beginning of a field width.'' * -- ANSI X3J11 */ flags |= ZEROPAD; 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 + todigit(*fmt); } while (isascii(*++fmt) && isdigit(*fmt)); width = n; --fmt; goto rflag; case 'L': flags |= LONGDBL; goto rflag; case 'h': flags |= SHORTINT; goto rflag; case 'l': flags |= LONGINT; goto rflag; case 'c': *(t = buf) = va_arg(argp, int); size = 1; sign = '\0'; goto pforw; case 'D': flags |= LONGINT; /*FALLTHROUGH*/ case 'd': case 'i': ARG(); if ((long)_ulong < 0) { _ulong = -_ulong; sign = '-'; } base = 10; goto number; case 'n': if (flags & LONGINT) *va_arg(argp, long *) = cnt; else if (flags & SHORTINT) *va_arg(argp, short *) = cnt; else *va_arg(argp, int *) = cnt; break; case 'O': flags |= LONGINT; /*FALLTHROUGH*/ case 'o': ARG(); base = 8; 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 = (u_long)va_arg(argp, void *); base = 16; goto nosign; case 's': if (!(t = va_arg(argp, char *))) t = "(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; for (p = t, size = 0; size < prec; p++, size++) if (*p == '\0') break; } else size = strlen(t); sign = '\0'; goto pforw; case 'U': flags |= LONGINT; /*FALLTHROUGH*/ case 'u': ARG(); base = 10; goto nosign; case 'X': digs = "0123456789ABCDEF"; /* FALLTHROUGH */ case 'x': ARG(); base = 16; /* 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 */ t = buf + BUF; if (_ulong != 0 || prec != 0) { do { *--t = digs[_ulong % base]; _ulong /= base; } while (_ulong); digs = "0123456789abcdef"; if (flags & ALT && base == 8 && *t != '0') *--t = '0'; /* octal leading 0 */ } size = buf + BUF - t; pforw: /* * All reasonable formats wind up here. At this point, * `t' 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 * fieldsz excludes decimal prec; realsz includes it */ fieldsz = size; if (sign) fieldsz++; if (flags & HEXPREFIX) fieldsz += 2; realsz = dprec > fieldsz ? dprec : fieldsz; /* right-adjusting blank padding */ if ((flags & (LADJUST|ZEROPAD)) == 0 && width) for (n = realsz; n < width; n++) PUTC(' '); /* prefix */ if (sign) PUTC(sign); if (flags & HEXPREFIX) { PUTC('0'); PUTC((char)*fmt); } /* right-adjusting zero padding */ if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) for (n = realsz; n < width; n++) PUTC('0'); /* leading zeroes from decimal precision */ for (n = fieldsz; n < dprec; n++) PUTC('0'); for (n = size; --n >= 0; ) PUTC(*t++); /* left-adjusting padding (always blank) */ if (flags & LADJUST) for (n = realsz; n < width; n++) PUTC(' '); /* finally, adjust cnt */ cnt += width > realsz ? width : realsz; break; case '\0': /* "%?" prints ?, unless ? is NULL */ return (cnt); default: PUTC((char)*fmt); cnt++; } } /* NOTREACHED */ }