Caterva has an internal structure managed by parameters that record the different properties of each dataset. The most fundamental parts of this structure are the Caterva context and the configuration parameters it depends on.

Context

struct caterva_ctx_t

Context for caterva arrays that specifies the functions used to manage memory and the compression/decompression parameters used in Blosc.

Configuration parameters

struct caterva_config_t

Configuration parameters used to create a caterva context.

Public Members

void *(*alloc)(size_t)

The memory allocation function used internally.

void (*free)(void*)

The memory release function used internally.

uint8_t compcodec

Defines the codec used in compression.

uint8_t compmeta

The metadata for the compressor codec.

uint8_t complevel

Determines the compression level used in Blosc.

int32_t splitmode

Whether the blocks should be split or not.

int usedict

Indicates whether a dictionary is used to compress data or not.

int16_t nthreads

Determines the maximum number of threads that can be used.

uint8_t filters[BLOSC2_MAX_FILTERS]

Defines the filters used in compression.

uint8_t filtersmeta[BLOSC2_MAX_FILTERS]

Indicates the meta filters used in Blosc.

blosc2_prefilter_fn prefilter

Defines the function that is applied to the data before compressing it.

blosc2_prefilter_params *pparams

Indicates the parameters of the prefilter function.

blosc2_btune *udbtune

Indicates user-defined parameters for btune.

static const caterva_config_t CATERVA_CONFIG_DEFAULTS

The default configuration parameters used in caterva.

Creation

int caterva_ctx_new(caterva_config_t *cfg, caterva_ctx_t **ctx)

Create a context for caterva.

Parameters

• cfg – The configuration parameters needed for the context creation.

• ctx – The memory pointer where the context will be created.

Returns

An error code.

Destruction

int caterva_ctx_free(caterva_ctx_t **ctx)

Free a context.

Parameters

ctx – The The context to be freed.

Returns

An error code.