Function nvpair_unpack_descriptor_array

freebsd/contrib/libnv/bsd_nvpair.c:1023–1072

#ifndef _KERNEL
const unsigned char *
nvpair_unpack_descriptor_array(bool isbe, nvpair_t *nvp,
    const unsigned char *ptr, size_t *leftp, const int *fds, size_t nfds)
{
	int64_t idx;
	size_t size;
	unsigned int ii;
	int *array;

	PJDLOG_ASSERT(nvp->nvp_type == NV_TYPE_DESCRIPTOR_ARRAY);

	size = sizeof(idx) * nvp->nvp_nitems;
	if (nvp->nvp_datasize != size || *leftp < size ||
	    nvp->nvp_nitems == 0 || size < nvp->nvp_nitems) {
		ERRNO_SET(EINVAL);
		return (NULL);
	}

	array = (int *)nv_malloc(size);
	if (array == NULL)
		return (NULL);

	for (ii = 0; ii < nvp->nvp_nitems; ii++) {
		if (isbe)
			idx = be64dec(ptr);
		else
			idx = le64dec(ptr);

		if (idx < 0) {
			ERRNO_SET(EINVAL);
			nv_free(array);
			return (NULL);
		}

		if ((size_t)idx >= nfds) {
			ERRNO_SET(EINVAL);
			nv_free(array);
			return (NULL);
		}

		array[ii] = (uint64_t)fds[idx];

		ptr += sizeof(idx);
		*leftp -= sizeof(idx);
	}

	nvp->nvp_data = (uint64_t)(uintptr_t)array;

	return (ptr);
}
#endif

const unsigned char *