bsd-snprintf.c

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					long long *num;
					num = va_arg(args, long long *);
					*num = currlen;
				} else {
					int *num;
					num = va_arg(args, int *);
					*num = currlen;
				}
				break;
			case '%':
				dopr_outch(buffer, &currlen, maxlen, ch);
				break;
			case 'w': /* not supported yet, treat as next char */
				ch = *format++;
				break;
			default: /* Unknown, skip */
			break;
			}
			ch = *format++;
			state = DP_S_DEFAULT;
			flags = cflags = min = 0;
			max = -1;
			break;
		case DP_S_DONE:
			break;
		default: /* hmm? */
			break; /* some picky compilers need this */
		}
	}
	if (currlen < maxlen - 1) 
		buffer[currlen] = '\0';
	else 
		buffer[maxlen - 1] = '\0';
}

static void
fmtstr(char *buffer, size_t *currlen, size_t maxlen,
    char *value, int flags, int min, int max)
{
	int cnt = 0, padlen, strln;     /* amount to pad */
  
	if (value == 0) 
		value = "<NULL>";

	for (strln = 0; strln < max && value[strln]; ++strln); /* strlen */
	padlen = min - strln;
	if (padlen < 0) 
		padlen = 0;
	if (flags & DP_F_MINUS) 
		padlen = -padlen; /* Left Justify */

	while ((padlen > 0) && (cnt < max)) {
		dopr_outch(buffer, currlen, maxlen, ' ');
		--padlen;
		++cnt;
	}
	while (*value && (cnt < max)) {
		dopr_outch(buffer, currlen, maxlen, *value++);
		++cnt;
	}
	while ((padlen < 0) && (cnt < max)) {
		dopr_outch(buffer, currlen, maxlen, ' ');
		++padlen;
		++cnt;
	}
}

/* Have to handle DP_F_NUM (ie 0x and 0 alternates) */

static void 
fmtint(char *buffer, size_t *currlen, size_t maxlen,
    long value, int base, int min, int max, int flags)
{
	unsigned long uvalue;
	char convert[20];
	int signvalue = 0, place = 0, caps = 0;
	int spadlen = 0; /* amount to space pad */
	int zpadlen = 0; /* amount to zero pad */
  
	if (max < 0)
		max = 0;

	uvalue = value;

	if (!(flags & DP_F_UNSIGNED)) {
		if (value < 0) {
			signvalue = '-';
			uvalue = -value;
		} else if (flags & DP_F_PLUS)  /* Do a sign (+/i) */
			signvalue = '+';
		else if (flags & DP_F_SPACE)
			signvalue = ' ';
	}
  
	if (flags & DP_F_UP) 
		caps = 1; /* Should characters be upper case? */
	do {
		convert[place++] =
		    (caps ? "0123456789ABCDEF" : "0123456789abcdef")
		    [uvalue % (unsigned)base];
		uvalue = (uvalue / (unsigned)base );
	} while (uvalue && (place < 20));
	if (place == 20) 
		place--;
	convert[place] = 0;

	zpadlen = max - place;
	spadlen = min - MAX (max, place) - (signvalue ? 1 : 0);
	if (zpadlen < 0)
		zpadlen = 0;
	if (spadlen < 0)
		spadlen = 0;
	if (flags & DP_F_ZERO) {
		zpadlen = MAX(zpadlen, spadlen);
		spadlen = 0;
	}
	if (flags & DP_F_MINUS) 
		spadlen = -spadlen; /* Left Justifty */

	/* Spaces */
	while (spadlen > 0) {
		dopr_outch(buffer, currlen, maxlen, ' ');
		--spadlen;
	}

	/* Sign */
	if (signvalue) 
		dopr_outch(buffer, currlen, maxlen, signvalue);

	/* Zeros */
	if (zpadlen > 0) {
		while (zpadlen > 0) {
			dopr_outch(buffer, currlen, maxlen, '0');
			--zpadlen;
		}
	}

	/* Digits */
	while (place > 0) 
		dopr_outch(buffer, currlen, maxlen, convert[--place]);
  
	/* Left Justified spaces */
	while (spadlen < 0) {
		dopr_outch (buffer, currlen, maxlen, ' ');
		++spadlen;
	}
}

static long double 
pow10(int exp)
{
	long double result = 1;

	while (exp) {
		result *= 10;
		exp--;
	}
  
	return result;
}

static long 
round(long double value)
{
	long intpart = value;

	value -= intpart;
	if (value >= 0.5)
		intpart++;

	return intpart;
}

static void 
fmtfp(char *buffer, size_t *currlen, size_t maxlen, long double fvalue, 
      int min, int max, int flags)
{
	char iconvert[20], fconvert[20];
	int signvalue = 0, iplace = 0, fplace = 0;
	int padlen = 0; /* amount to pad */
	int zpadlen = 0, caps = 0;
	long intpart, fracpart;
	long double ufvalue;
  
	/* 
	 * AIX manpage says the default is 0, but Solaris says the default
	 * is 6, and sprintf on AIX defaults to 6
	 */
	if (max < 0)
		max = 6;

	ufvalue = abs_val(fvalue);

	if (fvalue < 0)
		signvalue = '-';
	else if (flags & DP_F_PLUS)  /* Do a sign (+/i) */
		signvalue = '+';
	else if (flags & DP_F_SPACE)
		signvalue = ' ';

	intpart = ufvalue;

	/* 
	 * Sorry, we only support 9 digits past the decimal because of our 
	 * conversion method
	 */
	if (max > 9)
		max = 9;

	/* We "cheat" by converting the fractional part to integer by
	 * multiplying by a factor of 10
	 */
	fracpart = round((pow10 (max)) * (ufvalue - intpart));

	if (fracpart >= pow10 (max)) {
		intpart++;
		fracpart -= pow10 (max);
	}

	/* Convert integer part */
	do {
		iconvert[iplace++] =
		    (caps ? "0123456789ABCDEF" : "0123456789abcdef")
		    [intpart % 10];
		intpart = (intpart / 10);
	} while(intpart && (iplace < 20));
	if (iplace == 20) 
		iplace--;
	iconvert[iplace] = 0;

	/* Convert fractional part */
	do {
		fconvert[fplace++] =
		    (caps ? "0123456789ABCDEF" : "0123456789abcdef")
		    [fracpart % 10];
		fracpart = (fracpart / 10);
	} while(fracpart && (fplace < 20));
	if (fplace == 20) 
		fplace--;
	fconvert[fplace] = 0;

	/* -1 for decimal point, another -1 if we are printing a sign */
	padlen = min - iplace - max - 1 - ((signvalue) ? 1 : 0); 
	zpadlen = max - fplace;
	if (zpadlen < 0)
		zpadlen = 0;
	if (padlen < 0) 
		padlen = 0;
	if (flags & DP_F_MINUS) 
		padlen = -padlen; /* Left Justifty */

	if ((flags & DP_F_ZERO) && (padlen > 0)) {
		if (signvalue) {
			dopr_outch(buffer, currlen, maxlen, signvalue);
			--padlen;
			signvalue = 0;
		}
		while (padlen > 0) {
			dopr_outch(buffer, currlen, maxlen, '0');
			--padlen;
		}
	}
	while (padlen > 0) {
		dopr_outch(buffer, currlen, maxlen, ' ');
		--padlen;
	}
	if (signvalue) 
		dopr_outch(buffer, currlen, maxlen, signvalue);

	while (iplace > 0) 
		dopr_outch(buffer, currlen, maxlen, iconvert[--iplace]);

	/*
	 * Decimal point.  This should probably use locale to find the 
	 * correct char to print out.
	 */
	dopr_outch(buffer, currlen, maxlen, '.');

	while (fplace > 0) 
		dopr_outch(buffer, currlen, maxlen, fconvert[--fplace]);

	while (zpadlen > 0) {
		dopr_outch(buffer, currlen, maxlen, '0');
		--zpadlen;
	}

	while (padlen < 0) {
		dopr_outch(buffer, currlen, maxlen, ' ');
		++padlen;
	}
}

static void 
dopr_outch(char *buffer, size_t *currlen, size_t maxlen, char c)
{
	if (*currlen < maxlen)
		buffer[(*currlen)++] = c;
}
#endif /* !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF) */

#ifndef HAVE_VSNPRINTF
int 
vsnprintf(char *str, size_t count, const char *fmt, va_list args)
{
	str[0] = 0;
	dopr(str, count, fmt, args);

	return(strlen(str));
}
#endif /* !HAVE_VSNPRINTF */

#ifndef HAVE_SNPRINTF
int 
snprintf(char *str,size_t count,const char *fmt,...)
{
	va_list ap;

	va_start(ap, fmt);
	(void) vsnprintf(str, count, fmt, ap);
	va_end(ap);

	return(strlen(str));
}

#endif /* !HAVE_SNPRINTF */