snprintf.c

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	}
	if (flags & DP_F_MINUS) 
		spadlen = -spadlen; /* Left Justifty */

#ifdef DEBUG_SNPRINTF
	printf("zpad: %d, spad: %d, min: %d, max: %d, place: %d\n",
	       zpadlen, spadlen, min, max, place);
#endif

	/* 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 LDOUBLE abs_val(LDOUBLE value)
{
	LDOUBLE result = value;

	if (value < 0)
		result = -value;
	
	return result;
}

static LDOUBLE POW10(int exp)
{
	LDOUBLE result = 1;
	
	while (exp) {
		result *= 10;
		exp--;
	}
  
	return result;
}

static LLONG ROUND(LDOUBLE value)
{
	LLONG intpart;

	intpart = (LLONG)value;
	value = value - intpart;
	if (value >= 0.5) intpart++;
	
	return intpart;
}

/* a replacement for modf that doesn't need the math library. Should
   be portable, but slow */
static double my_modf(double x0, double *iptr)
{
	int i;
	long l;
	double x = x0;
	double f = 1.0;

	for (i=0;i<100;i++) {
		l = (long)x;
		if (l <= (x+1) && l >= (x-1)) break;
		x *= 0.1;
		f *= 10.0;
	}

	if (i == 100) {
		/* yikes! the number is beyond what we can handle. What do we do? */
		(*iptr) = 0;
		return 0;
	}

	if (i != 0) {
		double i2;
		double ret;

		ret = my_modf(x0-l*f, &i2);
		(*iptr) = l*f + i2;
		return ret;
	} 

	(*iptr) = l;
	return x - (*iptr);
}


static void fmtfp (char *buffer, size_t *currlen, size_t maxlen,
		   LDOUBLE fvalue, int min, int max, int flags)
{
	int signvalue = 0;
	double ufvalue;
	char iconvert[311];
	char fconvert[311];
	int iplace = 0;
	int fplace = 0;
	int padlen = 0; /* amount to pad */
	int zpadlen = 0; 
	int caps = 0;
	int index;
	double intpart;
	double fracpart;
	double temp;
  
	/* 
	 * 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 = ' ';
		}
	}

#if 0
	if (flags & DP_F_UP) caps = 1; /* Should characters be upper case? */
#endif

#if 0
	 if (max == 0) ufvalue += 0.5; /* if max = 0 we must round */
#endif

	/* 
	 * Sorry, we only support 16 digits past the decimal because of our 
	 * conversion method
	 */
	if (max > 16)
		max = 16;

	/* We "cheat" by converting the fractional part to integer by
	 * multiplying by a factor of 10
	 */

	temp = ufvalue;
	my_modf(temp, &intpart);

	fracpart = ROUND((POW10(max)) * (ufvalue - intpart));
	
	if (fracpart >= POW10(max)) {
		intpart++;
		fracpart -= POW10(max);
	}


	/* Convert integer part */
	do {
		temp = intpart;
		my_modf(intpart*0.1, &intpart);
		temp = temp*0.1;
		index = (int) ((temp -intpart +0.05)* 10.0);
		/* index = (int) (((double)(temp*0.1) -intpart +0.05) *10.0); */
		/* printf ("%llf, %f, %x\n", temp, intpart, index); */
		iconvert[iplace++] =
			(caps? "0123456789ABCDEF":"0123456789abcdef")[index];
	} while (intpart && (iplace < 311));
	if (iplace == 311) iplace--;
	iconvert[iplace] = 0;

	/* Convert fractional part */
	if (fracpart)
	{
		do {
			temp = fracpart;
			my_modf(fracpart*0.1, &fracpart);
			temp = temp*0.1;
			index = (int) ((temp -fracpart +0.05)* 10.0);
			/* index = (int) ((((temp/10) -fracpart) +0.05) *10); */
			/* printf ("%lf, %lf, %ld\n", temp, fracpart, index); */
			fconvert[fplace++] =
			(caps? "0123456789ABCDEF":"0123456789abcdef")[index];
		} while(fracpart && (fplace < 311));
		if (fplace == 311) 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]);

#ifdef DEBUG_SNPRINTF
	printf("fmtfp: fplace=%d zpadlen=%d\n", fplace, zpadlen);
#endif

	/*
	 * Decimal point.  This should probably use locale to find the correct
	 * char to print out.
	 */
	if (max > 0) {
		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;
	}
	(*currlen)++;
}

/* yes this really must be a ||. Don't muck with this (tridge) */
#if !defined(HAVE_VSNPRINTF) || !defined(HAVE_C99_VSNPRINTF)
 int vsnprintf (char *str, size_t count, const char *fmt, va_list args)
{
	return dopr(str, count, fmt, args);
}
#endif

/* yes this really must be a ||. Don't muck wiith this (tridge)
 *
 * The logic for these two is that we need our own definition if the
 * OS *either* has no definition of *sprintf, or if it does have one
 * that doesn't work properly according to the autoconf test.  Perhaps
 * these should really be smb_snprintf to avoid conflicts with buggy
 * linkers? -- mbp
 */
#if !defined(HAVE_SNPRINTF) || !defined(HAVE_C99_SNPRINTF)
 int snprintf(char *str,size_t count,const char *fmt,...)
{
	size_t ret;
	va_list ap;
    
	va_start(ap, fmt);
	ret = vsnprintf(str, count, fmt, ap);
	va_end(ap);
	return ret;
}
#endif

#endif 

#ifndef HAVE_VASPRINTF
 int vasprintf(char **ptr, const char *format, va_list ap)
{
	int ret;
	
	ret = vsnprintf(0, 0, format, ap);
	if (ret <= 0) return ret;

	(*ptr) = (char *)malloc(ret+1);
	if (!*ptr) return -1;
	ret = vsnprintf(*ptr, ret+1, format, ap);

	return ret;
}
#endif


#ifndef HAVE_ASPRINTF
 int asprintf(char **ptr, const char *format, ...)
{
	va_list ap;
	int ret;
	
	*ptr = 0;
	va_start(ap, format);
	ret = vasprintf(ptr, format, ap);
	va_end(ap);

	return ret;
}
#endif

#ifndef HAVE_VSYSLOG
#ifdef HAVE_SYSLOG
 void vsyslog (int facility_priority, char *format, va_list arglist)
{
	char *msg = 0;
	vasprintf(&msg, format, arglist);
        if (!msg)
                return;
        syslog(facility_priority, "%s", msg);
        free(msg);
}
#endif /* HAVE_SYSLOG */
#endif /* HAVE_VSYSLOG */

#ifdef TEST_SNPRINTF

 int sprintf(char *str,const char *fmt,...);

 int main (void)
{
	char buf1[1024];
	char buf2[1024];
	char *fp_fmt[] = {
		"%1.1f",
		"%-1.5f",
		"%1.5f",
		"%123.9f",
		"%10.5f",
		"% 10.5f",
		"%+22.9f",
		"%+4.9f",
		"%01.3f",
		"%4f",
		"%3.1f",
		"%3.2f",
		"%.0f",
		"%f",
		"-16.16f",
		0
	};
	double fp_nums[] = { 6442452944.1234, -1.5, 134.21, 91340.2, 341.1234, 0203.9, 0.96, 0.996, 
			     0.9996, 1.996, 4.136,  0};
	char *int_fmt[] = {
		"%-1.5d",
		"%1.5d",
		"%123.9d",
		"%5.5d",
		"%10.5d",
		"% 10.5d",
		"%+22.33d",
		"%01.3d",
		"%4d",
		"%d",
		0
	};
	long int_nums[] = { -1, 134, 91340, 341, 0203, 0};
	char *str_fmt[] = {
		"10.5s",
		"5.10s",
		"10.1s",
		"0.10s",
		"10.0s",
		"1.10s",
		"%s",
		"%.1s",
		"%.10s",
		"%10s",
		0
	};
	char *str_vals[] = {"hello", "a", "", "a longer string", 0};
	int x, y;
	int fail = 0;
	int num = 0;

	printf ("Testing snprintf format codes against system sprintf...\n");

	for (x = 0; fp_fmt[x] ; x++) {
		for (y = 0; fp_nums[y] != 0 ; y++) {
			int l1 = snprintf(0, 0, fp_fmt[x], fp_nums[y]);
			int l2 = snprintf(buf1, sizeof(buf1), fp_fmt[x], fp_nums[y]);
			sprintf (buf2, fp_fmt[x], fp_nums[y]);
			if (strcmp (buf1, buf2)) {
				printf("snprintf doesn't match Format: %s\n\tsnprintf = [%s]\n\t sprintf = [%s]\n", 
				       fp_fmt[x], buf1, buf2);
				fail++;
			}
			if (l1 != l2) {
				printf("snprintf l1 != l2 (%d %d) %s\n", l1, l2, fp_fmt[x]);
				fail++;
			}
			num++;
		}
	}

	for (x = 0; int_fmt[x] ; x++) {
		for (y = 0; int_nums[y] != 0 ; y++) {
			int l1 = snprintf(0, 0, int_fmt[x], int_nums[y]);
			int l2 = snprintf(buf1, sizeof(buf1), int_fmt[x], int_nums[y]);
			sprintf (buf2, int_fmt[x], int_nums[y]);
			if (strcmp (buf1, buf2)) {
				printf("snprintf doesn't match Format: %s\n\tsnprintf = [%s]\n\t sprintf = [%s]\n", 
				       int_fmt[x], buf1, buf2);
				fail++;
			}
			if (l1 != l2) {
				printf("snprintf l1 != l2 (%d %d) %s\n", l1, l2, int_fmt[x]);
				fail++;
			}
			num++;
		}
	}

	for (x = 0; str_fmt[x] ; x++) {
		for (y = 0; str_vals[y] != 0 ; y++) {
			int l1 = snprintf(0, 0, str_fmt[x], str_vals[y]);
			int l2 = snprintf(buf1, sizeof(buf1), str_fmt[x], str_vals[y]);
			sprintf (buf2, str_fmt[x], str_vals[y]);
			if (strcmp (buf1, buf2)) {
				printf("snprintf doesn't match Format: %s\n\tsnprintf = [%s]\n\t sprintf = [%s]\n", 
				       str_fmt[x], buf1, buf2);
				fail++;
			}
			if (l1 != l2) {
				printf("snprintf l1 != l2 (%d %d) %s\n", l1, l2, str_fmt[x]);
				fail++;
			}
			num++;
		}
	}

	printf ("%d tests failed out of %d.\n", fail, num);

	printf("seeing how many digits we support\n");
	{
		double v0 = 0.12345678901234567890123456789012345678901;
		for (x=0; x<100; x++) {
			snprintf(buf1, sizeof(buf1), "%1.1f", v0*pow(10, x));
			sprintf(buf2,                "%1.1f", v0*pow(10, x));
			if (strcmp(buf1, buf2)) {
				printf("we seem to support %d digits\n", x-1);
				break;
			}
		}
	}

	return 0;
}
#endif /* SNPRINTF_TEST */