Execution Units Prices¶

typedef struct cardano_ex_unit_prices_t cardano_ex_unit_prices_t¶

Specifies the cost (in Lovelace) of these ExUnits.

In essence, they set the “price” for the computational resources used by a smart contract.

cardano_error_t cardano_ex_unit_prices_new(cardano_unit_interval_t *memory_prices, cardano_unit_interval_t *steps_prices, cardano_ex_unit_prices_t **ex_unit_prices)¶

Creates and initializes a new instance of the execution unit prices.

This function allocates and initializes a new instance of the execution unit prices, representing the cost of computational resources used by a smart contract.

Usage Example:

cardano_ex_unit_prices_t* ex_unit_prices = NULL;
cardano_unit_interval_t* memory_prices = NULL;
cardano_unit_interval_t* steps_prices = NULL;
cardano_error_t result = CARDANO_SUCCESS;

// Initialize the unit intervals for memory and steps prices
result = cardano_unit_interval_from_double(0.003, &memory_prices);

if (result != CARDANO_SUCCESS)
{
  // Handle error
}

result = cardano_unit_interval_from_double(0.007, &steps_prices);

if (result != CARDANO_SUCCESS)
{
  // Handle error
}

// Attempt to create a new execution unit prices object
result = cardano_ex_unit_prices_new(memory_prices, steps_prices, &ex_unit_prices);

if (result == CARDANO_SUCCESS)
{
  // Use the ex_unit_prices

  // Once done, ensure to clean up and release the ex_unit_prices
  cardano_ex_unit_prices_unref(&ex_unit_prices);
}

// Clean up
cardano_unit_interval_unref(&memory_prices);
cardano_unit_interval_unref(&steps_prices);

Parameters:¶

cardano_unit_interval_t *memory_prices¶: [in] The price for memory consumption as a unit interval.
cardano_unit_interval_t *steps_prices¶: [in] The price for CPU steps as a unit interval.
cardano_ex_unit_prices_t **ex_unit_prices¶: [out] On successful initialization, this will point to a newly created execution unit prices object. This object represents a “strong reference”, meaning that it is fully initialized and ready for use. The caller is responsible for managing the lifecycle of this object. Specifically, once the execution unit prices is no longer needed, the caller must release it by calling cardano_ex_unit_prices_unref.

Returns:¶

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the execution unit prices was successfully created, or an appropriate error code indicating the failure reason.

cardano_error_t cardano_ex_unit_prices_from_cbor(cardano_cbor_reader_t *reader, cardano_ex_unit_prices_t **ex_unit_prices)¶

Creates a cardano_ex_unit_prices_t from a CBOR reader.

This function parses CBOR data using a provided cardano_cbor_reader_t and constructs a cardano_ex_unit_prices_t object. It assumes that the CBOR reader is set up correctly and that the CBOR data corresponds to the structure expected for a ex_unit_prices.

Usage Example:

cardano_cbor_reader_t* reader = cardano_cbor_reader_new(cbor_data, data_size);
cardano_ex_unit_prices_t* ex_unit_prices = NULL;

cardano_error_t result = cardano_ex_unit_prices_from_cbor(reader, &ex_unit_prices);

if (result == CARDANO_SUCCESS)
{
  // Use the ex_unit_prices

  // Once done, ensure to clean up and release the ex_unit_prices
  cardano_ex_unit_prices_unref(&ex_unit_prices);
}
else
{
  const char* error = cardano_cbor_reader_get_last_error(reader);
  printf("Failed to decode ex_unit_prices: %s\n", error);
}

cardano_cbor_reader_unref(&reader); // Cleanup the CBOR reader

Note

If the function fails, the last error can be retrieved by calling cardano_cbor_reader_get_last_error with the reader. The caller is responsible for freeing the created cardano_ex_unit_prices_t object by calling cardano_ex_unit_prices_unref when it is no longer needed.

Parameters:¶

cardano_cbor_reader_t *reader¶: [in] A pointer to an initialized cardano_cbor_reader_t that is ready to read the CBOR-encoded data.
cardano_ex_unit_prices_t **ex_unit_prices¶: [out] A pointer to a pointer of cardano_ex_unit_prices_t that will be set to the address of the newly created ex_unit_prices object upon successful decoding.

Returns:¶

A cardano_error_t value indicating the outcome of the operation. Returns CARDANO_SUCCESS if the object was successfully created, or an appropriate error code if an error occurred.

cardano_error_t cardano_ex_unit_prices_to_cbor(const cardano_ex_unit_prices_t *ex_unit_prices, cardano_cbor_writer_t *writer)¶

Serializes protocol version into CBOR format using a CBOR writer.

This function serializes the given cardano_ex_unit_prices_t object using a cardano_cbor_writer_t.

Usage Example:

cardano_ex_unit_prices_t* ex_unit_prices = ...;
cardano_cbor_writer_t* writer = cardano_cbor_writer_new();

if (writer)
{
  cardano_error_t result = cardano_ex_unit_prices_to_cbor(ex_unit_prices, writer);

  if (result == CARDANO_SUCCESS)
  {
    // Use the writer's buffer containing the serialized data
  }
  else
  {
    const char* error_message = cardano_cbor_writer_get_last_error(writer);
    printf("Serialization failed: %s\n", error_message);
  }

  cardano_cbor_writer_unref(&writer);
}

cardano_ex_unit_prices_unref(&ex_unit_prices);

Parameters:¶

const cardano_ex_unit_prices_t *ex_unit_prices¶: [in] A constant pointer to the cardano_ex_unit_prices_t object that is to be serialized.
cardano_cbor_writer_t *writer¶: [out] A pointer to a cardano_cbor_writer_t where the CBOR serialized data will be written. The writer must already be initialized and ready to accept the data.

Returns:¶

Returns CARDANO_SUCCESS if the serialization is successful. If the ex_unit_prices or writer is NULL, returns CARDANO_ERROR_POINTER_IS_NULL.

cardano_error_t cardano_ex_unit_prices_to_cip116_json(const cardano_ex_unit_prices_t *prices, cardano_json_writer_t *writer)¶

Serializes execution unit prices to CIP-116 JSON.

The function writes the full JSON object, including the surrounding braces. Keys are written in the order: “mem_price”, “step_price”.

Parameters:¶

const cardano_ex_unit_prices_t *prices¶: [in] Pointer to a valid cardano_ex_unit_prices_t.
cardano_json_writer_t *writer¶: [in] Pointer to a valid cardano_json_writer_t.

Returns:¶

CARDANO_SUCCESS On success. CARDANO_ERROR_POINTER_IS_NULL If prices or writer is NULL. Other Any error propagated from nested writers.

cardano_error_t cardano_ex_unit_prices_get_memory_prices(cardano_ex_unit_prices_t *ex_unit_prices, cardano_unit_interval_t **memory_prices)¶

Retrieves the memory price from the execution unit prices.

This function returns the memory price from the execution unit prices object.

Usage Example:

cardano_ex_unit_prices_t* ex_unit_prices = ...;
cardano_unit_interval_t* memory_prices = NULL;

// Assume ex_unit_prices is initialized properly
cardano_error_t result = cardano_ex_unit_prices_get_memory_prices(ex_unit_prices, &memory_prices);

if (result == CARDANO_SUCCESS)
{
  // Use the memory_prices
  // Clean up
  cardano_unit_interval_unref(&memory_prices);
}

cardano_ex_unit_prices_unref(&ex_unit_prices);

Parameters:¶

cardano_ex_unit_prices_t *ex_unit_prices¶: [in] Pointer to the execution unit prices object.
cardano_unit_interval_t **memory_prices¶: [out] On successful retrieval, this will point to the memory price as a unit interval.

Returns:¶

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the memory price was successfully retrieved, or an appropriate error code indicating the failure reason.

cardano_error_t cardano_ex_unit_prices_get_steps_prices(cardano_ex_unit_prices_t *ex_unit_prices, cardano_unit_interval_t **steps_prices)¶

Retrieves the steps price from the execution unit prices.

This function returns the steps price from the execution unit prices object.

Usage Example:

cardano_ex_unit_prices_t* ex_unit_prices = NULL;
cardano_unit_interval_t* steps_prices = NULL;

// Assume ex_unit_prices is initialized properly

cardano_error_t result = cardano_ex_unit_prices_get_steps_prices(ex_unit_prices, &steps_prices);

if (result == CARDANO_SUCCESS)
{
  // Use the steps_prices
  // Clean up
  cardano_unit_interval_unref(&steps_prices);
}

cardano_ex_unit_prices_unref(&ex_unit_prices);

Parameters:¶

cardano_ex_unit_prices_t *ex_unit_prices¶: [in] Pointer to the execution unit prices object.
cardano_unit_interval_t **steps_prices¶: [out] On successful retrieval, this will point to the steps price as a unit interval.

Returns:¶

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the steps price was successfully retrieved, or an appropriate error code indicating the failure reason.

cardano_error_t cardano_ex_unit_prices_set_memory_prices(cardano_ex_unit_prices_t *ex_unit_prices, cardano_unit_interval_t *memory_prices)¶

Sets the memory price in the execution unit prices.

This function sets the memory price in the execution unit prices object.

Usage Example:

cardano_ex_unit_prices_t* ex_unit_prices = NULL;
cardano_unit_interval_t* memory_prices = NULL;

// Assume ex_unit_prices and memory_prices are initialized properly

cardano_error_t result = cardano_ex_unit_prices_set_memory_prices(ex_unit_prices, memory_prices);

if (result == CARDANO_SUCCESS)
{
  // Memory price was successfully set
}

// Clean up
cardano_ex_unit_prices_unref(&ex_unit_prices);
cardano_unit_interval_unref(&memory_prices);

Parameters:¶

cardano_ex_unit_prices_t *ex_unit_prices¶: [in] Pointer to the execution unit prices object.
cardano_unit_interval_t *memory_prices¶: [in] Pointer to the unit interval representing the memory price.

Returns:¶

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the memory price was successfully set, or an appropriate error code indicating the failure reason.

cardano_error_t cardano_ex_unit_prices_set_steps_prices(cardano_ex_unit_prices_t *ex_unit_prices, cardano_unit_interval_t *steps_prices)¶

Sets the steps price in the execution unit prices.

This function sets the steps price in the execution unit prices object.

Usage Example:

cardano_ex_unit_prices_t* ex_unit_prices = NULL;
cardano_unit_interval_t* steps_prices = NULL;

// Assume ex_unit_prices and steps_prices are initialized properly

cardano_error_t result = cardano_ex_unit_prices_set_steps_prices(ex_unit_prices, steps_prices);

if (result == CARDANO_SUCCESS)
{
  // Steps price was successfully set
}

// Clean up
cardano_ex_unit_prices_unref(&ex_unit_prices);
cardano_unit_interval_unref(&steps_prices);

Parameters:¶

cardano_ex_unit_prices_t *ex_unit_prices¶: [in] Pointer to the execution unit prices object.
cardano_unit_interval_t *steps_prices¶: [in] Pointer to the unit interval representing the steps price.

Returns:¶

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the steps price was successfully set, or an appropriate error code indicating the failure reason.

void cardano_ex_unit_prices_unref(cardano_ex_unit_prices_t **ex_unit_prices)¶

Decrements the reference count of a cardano_ex_unit_prices_t object.

This function is responsible for managing the lifecycle of a cardano_ex_unit_prices_t object by decreasing its reference count. When the reference count reaches zero, the ex_unit_prices is finalized; its associated resources are released, and its memory is deallocated.

Usage Example:

cardano_ex_unit_prices_t* ex_unit_prices = cardano_ex_unit_prices_new(major, minor);

// Perform operations with the ex_unit_prices...

cardano_ex_unit_prices_unref(&ex_unit_prices);
// At this point, ex_unit_prices is NULL and cannot be used.

Note

After calling cardano_ex_unit_prices_unref, the pointer to the cardano_ex_unit_prices_t object will be set to NULL to prevent its reuse.

Parameters:¶

cardano_ex_unit_prices_t **ex_unit_prices¶: [inout] A pointer to the pointer of the ex_unit_prices object. This double indirection allows the function to set the caller’s pointer to NULL, avoiding dangling pointer issues after the object has been freed.

void cardano_ex_unit_prices_ref(cardano_ex_unit_prices_t *ex_unit_prices)¶

Increases the reference count of the cardano_ex_unit_prices_t object.

This function is used to manually increment the reference count of an cardano_ex_unit_prices_t object, indicating that another part of the code has taken ownership of it. This ensures the object remains allocated and valid until all owners have released their reference by calling cardano_ex_unit_prices_unref.

Usage Example:

// Assuming ex_unit_prices is a previously created ex_unit_prices object

cardano_ex_unit_prices_ref(ex_unit_prices);

// Now ex_unit_prices can be safely used elsewhere without worrying about premature deallocation

Note

Always ensure that for every call to cardano_ex_unit_prices_ref there is a corresponding call to cardano_ex_unit_prices_unref to prevent memory leaks.

Parameters:¶

cardano_ex_unit_prices_t *ex_unit_prices¶: A pointer to the cardano_ex_unit_prices_t object whose reference count is to be incremented.

size_t cardano_ex_unit_prices_refcount(const cardano_ex_unit_prices_t *ex_unit_prices)¶

Retrieves the current reference count of the cardano_ex_unit_prices_t object.

This function returns the number of active references to an cardano_ex_unit_prices_t object. It’s useful for debugging purposes or managing the lifecycle of the object in complex scenarios.

Usage Example:

// Assuming ex_unit_prices is a previously created ex_unit_prices object

size_t ref_count = cardano_ex_unit_prices_refcount(ex_unit_prices);

printf("Reference count: %zu\n", ref_count);

Warning

This function does not account for transitive references. A transitive reference occurs when an object holds a reference to another object, rather than directly to the cardano_ex_unit_prices_t. As such, the reported count may not fully represent the total number of conceptual references in cases where such transitive relationships exist.

Parameters:¶

const cardano_ex_unit_prices_t *ex_unit_prices¶: A pointer to the cardano_ex_unit_prices_t object whose reference count is queried. The object must not be NULL.

Returns:¶

The number of active references to the specified cardano_ex_unit_prices_t object. If the object is properly managed (i.e., every cardano_ex_unit_prices_ref call is matched with a cardano_ex_unit_prices_unref call), this count should reach zero right before the object is deallocated.

void cardano_ex_unit_prices_set_last_error(cardano_ex_unit_prices_t *ex_unit_prices, const char *message)¶

Sets the last error message for a given cardano_ex_unit_prices_t object.

Records an error message in the ex_unit_prices’s last_error buffer, overwriting any existing message. This is useful for storing descriptive error information that can be later retrieved. The message is truncated if it exceeds the buffer’s capacity.

Note

The error message is limited to 1023 characters, including the null terminator, due to the fixed size of the last_error buffer.

Parameters:¶

cardano_ex_unit_prices_t *ex_unit_prices¶: [in] A pointer to the cardano_ex_unit_prices_t instance whose last error message is to be set. If NULL, the function does nothing.
const char *message¶: [in] A null-terminated string containing the error message. If NULL, the ex_unit_prices’s last_error is set to an empty string, indicating no error.

const char *cardano_ex_unit_prices_get_last_error(const cardano_ex_unit_prices_t *ex_unit_prices)¶

Retrieves the last error message recorded for a specific ex_unit_prices.

This function returns a pointer to the null-terminated string containing the last error message set by cardano_ex_unit_prices_set_last_error for the given ex_unit_prices. If no error message has been set, or if the last_error buffer was explicitly cleared, an empty string is returned, indicating no error.

Note

The returned string points to internal storage within the object and must not be modified by the caller. The string remains valid until the next call to cardano_ex_unit_prices_set_last_error for the same ex_unit_prices, or until the ex_unit_prices is deallocated.

Parameters:¶

const cardano_ex_unit_prices_t *ex_unit_prices¶: [in] A pointer to the cardano_ex_unit_prices_t instance whose last error message is to be retrieved. If the ex_unit_prices is NULL, the function returns a generic error message indicating the null ex_unit_prices.

Returns:¶

A pointer to a null-terminated string containing the last error message for the specified ex_unit_prices. If the ex_unit_prices is NULL, “Object is NULL.” is returned to indicate the error.