Function xmlSchemaFormatFloat

ThirdParty/libxml2/vtklibxml2/xmlschemastypes.c:5800–5857

* xmlXPathFormatNumber: * @number: number to format * @buffer: output buffer * @buffersize: size of output buffer * * Convert the number into a string representation. */

 * Convert the number into a string representation.
 */
static void
xmlSchemaFormatFloat(double number, char buffer[], int buffersize)
{
    switch (xmlXPathIsInf(number)) {
    case 1:
	if (buffersize > (int)sizeof("INF"))
	    snprintf(buffer, buffersize, "INF");
	break;
    case -1:
	if (buffersize > (int)sizeof("-INF"))
	    snprintf(buffer, buffersize, "-INF");
	break;
    default:
	if (xmlXPathIsNaN(number)) {
	    if (buffersize > (int)sizeof("NaN"))
		snprintf(buffer, buffersize, "NaN");
	} else if (number == 0) {
	    snprintf(buffer, buffersize, "0.0E0");
	} else {
	    /* 3 is sign, decimal point, and terminating zero */
	    char work[DBL_DIG + EXPONENT_DIGITS + 3];
	    int integer_place, fraction_place;
	    char *ptr;
	    char *after_fraction;
	    double absolute_value;
	    int size;

	    absolute_value = fabs(number);

	    /*
	     * Result is in work, and after_fraction points
	     * just past the fractional part.
	     * Use scientific notation
	    */
	    integer_place = DBL_DIG + EXPONENT_DIGITS + 1;
	    fraction_place = DBL_DIG - 1;
	    snprintf(work, sizeof(work),"%*.*e",
		integer_place, fraction_place, number);
	    after_fraction = strchr(work + DBL_DIG, 'e');
	    /* Remove fractional trailing zeroes */
	    ptr = after_fraction;
	    while (*(--ptr) == '0')
		;
	    if (*ptr != '.')
	        ptr++;
	    while ((*ptr++ = *after_fraction++) != 0);

	    /* Finally copy result back to caller */
	    size = strlen(work) + 1;
	    if (size > buffersize) {
		work[buffersize - 1] = 0;
		size = buffersize;
	    }
	    memmove(buffer, work, size);
	}
	break;
    }
}