shadow/lib/snprintf.c

321 lines
9.2 KiB
C

/**************************************************************
* Original:
* Patrick Powell Tue Apr 11 09:48:21 PDT 1995
* A bombproof version of doprnt (dopr) included.
* Sigh. This sort of thing is always nasty do deal with. Note that
* the version here does not include floating point...
*
* snprintf() is used instead of sprintf() as it does limit checks
* for string length. This covers a nasty loophole.
*
* The other functions are there to prevent NULL pointers from
* causing nast effects.
**************************************************************/
/* $XFree86: xc/lib/misc/snprintf.c,v 3.0 1996/08/26 06:19:23 dawes Exp $ */
#include <ctype.h>
#include "snprintf.h"
static void dopr();
static char *end;
/* varargs declarations: */
#if defined(HAVE_STDARG_H)
# include <stdarg.h>
# define HAVE_STDARGS /* let's hope that works everywhere (mj) */
# define VA_LOCAL_DECL va_list ap;
# define VA_START(f) va_start(ap, f)
# define VA_SHIFT(v,t) ; /* no-op for ANSI */
# define VA_END va_end(ap)
#else
# if defined(HAVE_VARARGS_H)
# include <varargs.h>
# undef HAVE_STDARGS
# define VA_LOCAL_DECL va_list ap;
# define VA_START(f) va_start(ap) /* f is ignored! */
# define VA_SHIFT(v,t) v = va_arg(ap,t)
# define VA_END va_end(ap)
# else
/*XX ** NO VARARGS ** XX*/
# endif
#endif
#ifdef HAVE_STDARGS
int snprintf (char *str, size_t count, const char *fmt, ...);
int vsnprintf (char *str, size_t count, const char *fmt, va_list arg);
#else
int snprintf ();
int vsnprintf ();
#endif
int
vsnprintf(str, count, fmt, args)
char *str;
size_t count;
const char *fmt;
va_list args;
{
str[0] = 0;
end = str+count-1;
dopr( str, fmt, args );
if( count>0 ){
end[0] = 0;
}
return(strlen(str));
}
/* VARARGS3 */
#ifdef HAVE_STDARGS
int
snprintf (char *str,size_t count,const char *fmt,...)
#else
int
snprintf (va_alist) va_dcl
#endif
{
#ifndef HAVE_STDARGS
char *str;
size_t count;
char *fmt;
#endif
VA_LOCAL_DECL
VA_START (fmt);
VA_SHIFT (str, char *);
VA_SHIFT (count, size_t );
VA_SHIFT (fmt, char *);
(void) vsnprintf ( str, count, fmt, ap);
VA_END;
return( strlen( str ) );
}
/*
* dopr(): poor man's version of doprintf
*/
static void fmtstr(
#if NeedFunctionPrototypes
char *value, int ljust, int len, int zpad
#endif
);
static void fmtnum(
#if NeedFunctionPrototypes
long value, int base, int dosign, int ljust, int len, int zpad
#endif
);
static void dostr(
#if NeedFunctionPrototypes
char *
#endif
);
static char *output;
static void dopr_outch(
#if NeedFunctionPrototypes
int c
#endif
);
static void
dopr( buffer, format, args )
char *buffer;
char *format;
va_list args;
{
int ch;
long value;
int longflag = 0;
char *strvalue;
int ljust;
int len;
int zpad;
output = buffer;
while( (ch = *format++) ){
switch( ch ){
case '%':
ljust = len = zpad = 0;
nextch:
ch = *format++;
switch( ch ){
case 0:
dostr( "**end of format**" );
return;
case '-': ljust = 1; goto nextch;
case '0': /* set zero padding if len not set */
if(len==0) zpad = '0';
case '1': case '2': case '3':
case '4': case '5': case '6':
case '7': case '8': case '9':
len = len*10 + ch - '0';
goto nextch;
case 'l': longflag = 1; goto nextch;
case 'u': case 'U':
/*fmtnum(value,base,dosign,ljust,len,zpad) */
if( longflag ){
value = va_arg( args, long );
} else {
value = va_arg( args, int );
}
fmtnum( value, 10,0, ljust, len, zpad ); break;
case 'o': case 'O':
/*fmtnum(value,base,dosign,ljust,len,zpad) */
if( longflag ){
value = va_arg( args, long );
} else {
value = va_arg( args, int );
}
fmtnum( value, 8,0, ljust, len, zpad ); break;
case 'd': case 'D':
if( longflag ){
value = va_arg( args, long );
} else {
value = va_arg( args, int );
}
fmtnum( value, 10,1, ljust, len, zpad ); break;
case 'x':
if( longflag ){
value = va_arg( args, long );
} else {
value = va_arg( args, int );
}
fmtnum( value, 16,0, ljust, len, zpad ); break;
case 'X':
if( longflag ){
value = va_arg( args, long );
} else {
value = va_arg( args, int );
}
fmtnum( value,-16,0, ljust, len, zpad ); break;
case 's':
strvalue = va_arg( args, char *);
fmtstr( strvalue,ljust,len,zpad ); break;
case 'c':
ch = va_arg( args, int );
dopr_outch( ch ); break;
case '%': dopr_outch( ch ); continue;
default:
dostr( "???????" );
}
longflag = 0;
break;
default:
dopr_outch( ch );
break;
}
}
*output = 0;
}
static void
fmtstr( value, ljust, len, zpad )
char *value;
int ljust, len, zpad;
{
int padlen, strlen; /* amount to pad */
if( value == 0 ){
value = "<NULL>";
}
for( strlen = 0; value[strlen]; ++ strlen ); /* strlen */
padlen = len - strlen;
if( padlen < 0 ) padlen = 0;
if( ljust ) padlen = -padlen;
while( padlen > 0 ) {
dopr_outch( ' ' );
--padlen;
}
dostr( value );
while( padlen < 0 ) {
dopr_outch( ' ' );
++padlen;
}
}
static void
fmtnum( value, base, dosign, ljust, len, zpad )
long value;
int base, dosign, ljust, len, zpad;
{
int signvalue = 0;
unsigned long uvalue;
char convert[20];
int place = 0;
int padlen = 0; /* amount to pad */
int caps = 0;
/* DEBUGP(("value 0x%x, base %d, dosign %d, ljust %d, len %d, zpad %d\n",
value, base, dosign, ljust, len, zpad )); */
uvalue = value;
if( dosign ){
if( value < 0 ) {
signvalue = '-';
uvalue = -value;
}
}
if( base < 0 ){
caps = 1;
base = -base;
}
do{
convert[place++] =
(caps? "0123456789ABCDEF":"0123456789abcdef")
[uvalue % (unsigned)base ];
uvalue = (uvalue / (unsigned)base );
}while(uvalue);
convert[place] = 0;
padlen = len - place;
if( padlen < 0 ) padlen = 0;
if( ljust ) padlen = -padlen;
/* DEBUGP(( "str '%s', place %d, sign %c, padlen %d\n",
convert,place,signvalue,padlen)); */
if( zpad && padlen > 0 ){
if( signvalue ){
dopr_outch( signvalue );
--padlen;
signvalue = 0;
}
while( padlen > 0 ){
dopr_outch( zpad );
--padlen;
}
}
while( padlen > 0 ) {
dopr_outch( ' ' );
--padlen;
}
if( signvalue ) dopr_outch( signvalue );
while( place > 0 ) dopr_outch( convert[--place] );
while( padlen < 0 ){
dopr_outch( ' ' );
++padlen;
}
}
static void
dostr( str )
char *str;
{
while(*str) dopr_outch(*str++);
}
static void
dopr_outch( c )
int c;
{
if( iscntrl(c) && c != '\n' && c != '\t' ){
c = '@' + (c & 0x1F);
if( end == 0 || output < end ){
*output++ = '^';
}
}
if( end == 0 || output < end ){
*output++ = c;
}
}