text-util.c

#include "text-util.h"
#include "util.h"
#include <wchar.h>
#include <errno.h>

bool text_range_valid(Filerange *r) {
	return r->start != EPOS && r->end != EPOS && r->start <= r->end;
}

size_t text_range_size(Filerange *r) {
	return text_range_valid(r) ? r->end - r->start : 0;
}

Filerange text_range_empty(void) {
	return (Filerange){ .start = EPOS, .end = EPOS };
}

Filerange text_range_union(Filerange *r1, Filerange *r2) {
	if (!text_range_valid(r1))
		return *r2;
	if (!text_range_valid(r2))
		return *r1;
	return (Filerange) {
		.start = MIN(r1->start, r2->start),
		.end = MAX(r1->end, r2->end),
	};
}

Filerange text_range_new(size_t a, size_t b) {
	return (Filerange) {
		.start = MIN(a, b),
		.end = MAX(a, b),
	};
}

bool text_range_equal(Filerange *r1, Filerange *r2) {
	if (!text_range_valid(r1) && !text_range_valid(r2))
		return true;
	return r1->start == r2->start && r1->end == r2->end;
}

bool text_range_overlap(Filerange *r1, Filerange *r2) {
	if (!text_range_valid(r1) || !text_range_valid(r2))
		return false;
	return r1->start <= r2->end && r2->start <= r1->end;
}

bool text_range_contains(Filerange *r, size_t pos) {
	return text_range_valid(r) && r->start <= pos && pos <= r->end;
}

int text_char_count(const char *data, size_t len) {
	int count = 0;
	mbstate_t ps = { 0 };
	while (len > 0) {
		wchar_t wc;
		size_t wclen = mbrtowc(&wc, data, len, &ps);
		if (wclen == (size_t)-1 && errno == EILSEQ) {
			count++;
			while (!ISUTF8(*data))
				data++, len--;
		} else if (wclen == (size_t)-2) {
			break;
                } else if (wclen == 0) {
			count++;
			data++;
			len--;
		} else {
			int width = wcwidth(wc);
			if (width != 0)
				count++;
			data += wclen;
			len -= wclen;
                }
	}
	return count;
}