/*
* Given a valid ncp, return NC_EVARSIZE if any variable has a bad len
* (product of non-rec dim sizes too large), else return NC_NOERR.
*/
static int
NC_check_vlens(NC *ncp)
{
NC_var **vpp;
/* maximum permitted variable size (or size of one record's worth
of a record variable) in bytes. This is different for format 1
and format 2. */
size_t vlen_max;
size_t ii;
size_t large_vars_count;
size_t rec_vars_count;
int last = 0;
if(ncp->vars.nelems == 0)
return NC_NOERR;
if ((ncp->flags & NC_64BIT_OFFSET) && sizeof(off_t) > 4) {
/* CDF2 format and LFS */
vlen_max = X_UINT_MAX - 3; /* "- 3" handles rounded-up size */
} else {
/* CDF1 format */
vlen_max = X_INT_MAX - 3;
}
/* Loop through vars, first pass is for non-record variables. */
large_vars_count = 0;
rec_vars_count = 0;
vpp = ncp->vars.value;
for (ii = 0; ii < ncp->vars.nelems; ii++, vpp++) {
if( !IS_RECVAR(*vpp) ) {
last = 0;
if( NC_check_vlen(*vpp, vlen_max) == 0 ) {
large_vars_count++;
last = 1;
}
} else {
rec_vars_count++;
}
}
/* OK if last non-record variable size too large, since not used to
compute an offset */
if( large_vars_count > 1) { /* only one "too-large" variable allowed */
return NC_EVARSIZE;
}
/* and it has to be the last one */
if( large_vars_count == 1 && last == 0) {
return NC_EVARSIZE;
}
if( rec_vars_count > 0 ) {
/* and if it's the last one, there can't be any record variables */
if( large_vars_count == 1 && last == 1) {
return NC_EVARSIZE;
}
/* Loop through vars, second pass is for record variables. */
large_vars_count = 0;
vpp = ncp->vars.value;
for (ii = 0; ii < ncp->vars.nelems; ii++, vpp++) {
if( IS_RECVAR(*vpp) ) {
last = 0;
if( NC_check_vlen(*vpp, vlen_max) == 0 ) {
large_vars_count++;
last = 1;
}
}
}
/* OK if last record variable size too large, since not used to
compute an offset */
if( large_vars_count > 1) { /* only one "too-large" variable allowed */
return NC_EVARSIZE;
}
/* and it has to be the last one */
if( large_vars_count == 1 && last == 0) {
return NC_EVARSIZE;
}
}
return NC_NOERR;
}
/*
* 'compile' the shape and len of a variable
* Formerly
NC_var_shape(var, dims)
*/
int
NC_var_shape(NC_var *varp, const NC_dimarray *dims)
{
size_t *shp, *op;
off_t *dsp;
int *ip = NULL;
const NC_dim *dimp;
off_t product = 1;
varp->xsz = ncx_szof(varp->type);
if(varp->ndims == 0 || varp->dimids == NULL)
{
goto out;
}
/*
* use the user supplied dimension indices
* to determine the shape
*/
for(ip = varp->dimids, op = varp->shape
; ip < &varp->dimids[varp->ndims]; ip++, op++)
{
if(*ip < 0 || (size_t) (*ip) >= ((dims != NULL) ? dims->nelems : 1) )
return NC_EBADDIM;
dimp = elem_NC_dimarray(dims, (size_t)*ip);
*op = dimp->size;
if(*op == NC_UNLIMITED && ip != varp->dimids)
return NC_EUNLIMPOS;
}
/*
* Compute the dsizes
*/
/* ndims is > 0 here */
for(shp = varp->shape + varp->ndims -1,
dsp = varp->dsizes + varp->ndims -1;
shp >= varp->shape;
shp--, dsp--)
{
/*if(!(shp == varp->shape && IS_RECVAR(varp)))*/
if( shp != NULL && (shp != varp->shape || !IS_RECVAR(varp)))
{
if( ((off_t)(*shp)) <= OFF_T_MAX / product )
{
product *= (*shp > 0 ? *shp : 1);
} else
{
product = OFF_T_MAX ;
}
}
*dsp = product;
}
out :
/* No variable size can be > X_INT64_MAX - 3 */
if (0 == NC_check_vlen(varp, X_INT64_MAX-3)) return NC_EVARSIZE;
/*
* For CDF-1 and CDF-2 formats, the total number of array elements
* cannot exceed 2^32, unless this variable is the last fixed-size
* variable, there is no record variable, and the file starting
* offset of this variable is less than 2GiB.
* This will be checked in NC_check_vlens() during NC_endef()
*/
varp->len = product * varp->xsz;
if (varp->len % 4 > 0)
varp->len += 4 - varp->len % 4; /* round up */
#if 0
arrayp("\tshape", varp->ndims, varp->shape);
arrayp("\tdsizes", varp->ndims, varp->dsizes);
#endif
return NC_NOERR;
}
