libcharconv_counting_rods.c


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/* See LICENSE file for copyright and license details. */
#include "lib-common.h"


enum libcharconv_result
libcharconv_counting_rods(const char *s, size_t slen, size_t *n, uint_least32_t *cp, size_t *ncp)
{
	uint_least32_t c;
	*n = 0;
	for (; slen--; s++) {
		if ('1' <= *s && *s <= '9') {
			c = UINT32_C(0x13D60) + (unsigned)(*s - '1');
			if (!slen)
				goto conv_if_end;
			if (s[1] != '0')
				goto conv1;
			c += 9u;
			goto conv2;
		} else {
			*n += 1u;
		}
	}
no_conv:
	return LIBCHARCONV_NO_CONVERT;

conv_if_end:
	if (*n)
		goto no_conv;
	if (*ncp)
		*cp = c;
	*n += 1u;
	*ncp = 1u;
	return LIBCHARCONV_CONVERT_IF_END;

conv1:
	if (*n)
		goto no_conv;
	if (*ncp)
		*cp = c;
	*n += 1u;
	*ncp = 1u;
	return LIBCHARCONV_CONVERTED;

conv2:
	if (*n)
		goto no_conv;
	if (*ncp)
		*cp = c;
	*n += 2u;
	*ncp = 1u;
	return LIBCHARCONV_CONVERTED;
}