freebsd-skq/contrib/tcp_wrappers/vfprintf.c
1999-03-14 17:13:19 +00:00

126 lines
3.1 KiB
C

/*
* vfprintf() and vprintf() clones. They will produce unexpected results
* when excessive dynamic ("*") field widths are specified. To be used for
* testing purposes only.
*
* Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
*/
#ifndef lint
static char sccsid[] = "@(#) vfprintf.c 1.2 94/03/23 17:44:46";
#endif
#include <stdio.h>
#include <ctype.h>
#ifdef __STDC__
#include <stdarg.h>
#else
#include <varargs.h>
#endif
/* vfprintf - print variable-length argument list to stream */
int vfprintf(fp, format, ap)
FILE *fp;
char *format;
va_list ap;
{
char fmt[BUFSIZ]; /* format specifier */
register char *fmtp;
register char *cp;
int count = 0;
/*
* Iterate over characters in the format string, picking up arguments
* when format specifiers are found.
*/
for (cp = format; *cp; cp++) {
if (*cp != '%') {
putc(*cp, fp); /* ordinary character */
count++;
} else {
/*
* Format specifiers are handled one at a time, since we can only
* deal with arguments one at a time. Try to determine the end of
* the format specifier. We do not attempt to fully parse format
* strings, since we are ging to let fprintf() do the hard work.
* In regular expression notation, we recognize:
*
* %-?0?([0-9]+|\*)?\.?([0-9]+|\*)?l?[a-z]
*
* which includes some combinations that do not make sense.
*/
fmtp = fmt;
*fmtp++ = *cp++;
if (*cp == '-') /* left-adjusted field? */
*fmtp++ = *cp++;
if (*cp == '0') /* zero-padded field? */
*fmtp++ = *cp++;
if (*cp == '*') { /* dynamic field witdh */
sprintf(fmtp, "%d", va_arg(ap, int));
fmtp += strlen(fmtp);
cp++;
} else {
while (isdigit(*cp)) /* hard-coded field width */
*fmtp++ = *cp++;
}
if (*cp == '.') /* width/precision separator */
*fmtp++ = *cp++;
if (*cp == '*') { /* dynamic precision */
sprintf(fmtp, "%d", va_arg(ap, int));
fmtp += strlen(fmtp);
cp++;
} else {
while (isdigit(*cp)) /* hard-coded precision */
*fmtp++ = *cp++;
}
if (*cp == 'l') /* long whatever */
*fmtp++ = *cp++;
if (*cp == 0) /* premature end, punt */
break;
*fmtp++ = *cp; /* type (checked below) */
*fmtp = 0;
/* Execute the format string - let fprintf() do the hard work. */
switch (fmtp[-1]) {
case 's': /* string-valued argument */
count += fprintf(fp, fmt, va_arg(ap, char *));
break;
case 'c': /* integral-valued argument */
case 'd':
case 'u':
case 'o':
case 'x':
if (fmtp[-2] == 'l')
count += fprintf(fp, fmt, va_arg(ap, long));
else
count += fprintf(fp, fmt, va_arg(ap, int));
break;
case 'e': /* float-valued argument */
case 'f':
case 'g':
count += fprintf(fp, fmt, va_arg(ap, double));
break;
default: /* anything else */
putc(fmtp[-1], fp);
count++;
break;
}
}
}
return (count);
}
/* vprintf - print variable-length argument list to stdout */
vprintf(format, ap)
char *format;
va_list ap;
{
return (vfprintf(stdout, format, ap));
}