libquanta_palette_size.c


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


int
libquanta_palette_size(size_t ncolours, size_t nchannels, size_t *size_out)
{
	if (!ncolours || !nchannels) {
		errno = EINVAL;
		return -1;
	}

	if (ncolours > (SIZE_MAX - PALETTE_BASE_SIZE) / PALETTE_VALUE_SIZE / nchannels) {
		errno = EOVERFLOW;
		return -1;
	}

	if (size_out)
		*size_out = PALETTE_BASE_SIZE + ncolours * nchannels * PALETTE_VALUE_SIZE;

	return 0;
}