Sub Transaction Set¶

typedef struct cardano_sub_transaction_set_t cardano_sub_transaction_set_t¶

Represents the set of sub transactions carried by a transaction body (the sub transactions transaction body field).

Sub transactions let several parties compose intents that are validated and applied atomically as part of a single top-level transaction.

On the wire this field is a non-empty array of sub transactions, optionally wrapped in CBOR tag 258. The ledger models the field as an ordered map keyed by sub transaction id, but the ids are never serialized; each id is derived by hashing the sub transaction body (blake2b-256). The set preserves insertion order and rejects two sub transactions with the same id.

cardano_error_t cardano_sub_transaction_set_new(cardano_sub_transaction_set_t **sub_transaction_set)¶

Creates and initializes a new instance of a sub_transaction_set.

This function allocates and initializes a new instance of cardano_sub_transaction_set_t. It returns an error code to indicate success or failure of the operation.

Usage Example:

cardano_sub_transaction_set_t* sub_transaction_set = NULL;

// Attempt to create a new sub_transaction_set
cardano_error_t result = cardano_sub_transaction_set_new(&sub_transaction_set);

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

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

Parameters:¶

cardano_sub_transaction_set_t **sub_transaction_set¶: [out] On successful initialization, this will point to a newly created cardano_sub_transaction_set_t object. This object represents a “strong reference” to the sub_transaction_set, meaning that it is fully initialized and ready for use. The caller is responsible for managing the lifecycle of this object. Specifically, once the sub_transaction_set is no longer needed, the caller must release it by calling cardano_sub_transaction_set_unref.

Returns:¶

CARDANO_SUCCESS if the sub_transaction_set was successfully created, or an appropriate error code indicating the failure reason.

cardano_error_t cardano_sub_transaction_set_from_cbor(cardano_cbor_reader_t *reader, cardano_sub_transaction_set_t **sub_transaction_set)¶

Creates a sub transaction set from a CBOR reader.

This function parses CBOR data using a provided cardano_cbor_reader_t and constructs a cardano_sub_transaction_set_t object. The set accepts both wire forms, with or without the set tag (258): an array of sub transactions. An empty set is a decoding error, as are two sub transactions with the same id (the blake2b-256 hash of the sub transaction body).

Usage Example:

cardano_cbor_reader_t* reader = cardano_cbor_reader_new(cbor_data, data_size);
cardano_sub_transaction_set_t* sub_transaction_set = NULL;

cardano_error_t result = cardano_sub_transaction_set_from_cbor(reader, &sub_transaction_set);

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

  // Once done, ensure to clean up and release the sub_transaction_set
  cardano_sub_transaction_set_unref(&sub_transaction_set);
}
else
{
  const char* error = cardano_cbor_reader_get_last_error(reader);
  printf("Failed to decode sub_transaction_set: %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_sub_transaction_set_t object by calling cardano_sub_transaction_set_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 sub transaction set data.
cardano_sub_transaction_set_t **sub_transaction_set¶: [out] A pointer to a pointer of cardano_sub_transaction_set_t that will be set to the address of the newly created sub_transaction_set object upon successful decoding.

Returns:¶

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

cardano_error_t cardano_sub_transaction_set_to_cbor(const cardano_sub_transaction_set_t *sub_transaction_set, cardano_cbor_writer_t *writer)¶

Serializes a sub transaction set into CBOR format using a CBOR writer.

This function serializes the given cardano_sub_transaction_set_t object using a cardano_cbor_writer_t. The set is written as an array of sub transactions in insertion order. The array is wrapped in CBOR tag 258 unless the set was decoded from an untagged array, in which case the untagged form is preserved so that the set round-trips byte-exactly.

Usage Example:

cardano_sub_transaction_set_t* sub_transaction_set = ...;
cardano_cbor_writer_t* writer = cardano_cbor_writer_new();

if (writer)
{
  cardano_error_t result = cardano_sub_transaction_set_to_cbor(sub_transaction_set, 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_sub_transaction_set_unref(&sub_transaction_set);

Parameters:¶

const cardano_sub_transaction_set_t *sub_transaction_set¶: [in] A constant pointer to the cardano_sub_transaction_set_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 sub_transaction_set or writer is NULL, returns CARDANO_ERROR_POINTER_IS_NULL.

size_t cardano_sub_transaction_set_get_length(const cardano_sub_transaction_set_t *sub_transaction_set)¶

Retrieves the length of a sub transaction set.

This function retrieves the number of elements in the provided cardano_sub_transaction_set_t object.

Usage Example:

cardano_sub_transaction_set_t* sub_transaction_set = NULL;
cardano_error_t result = cardano_sub_transaction_set_new(&sub_transaction_set);

// Populate sub_transaction_set with elements

size_t length = cardano_sub_transaction_set_get_length(sub_transaction_set);
printf("Length of the sub_transaction_set: %zu\n", length);

// Clean up the sub_transaction_set object once done
cardano_sub_transaction_set_unref(&sub_transaction_set);

Parameters:¶

const cardano_sub_transaction_set_t *sub_transaction_set¶: [in] A constant pointer to the cardano_sub_transaction_set_t object whose length is to be retrieved.

Returns:¶

The number of elements in the sub_transaction_set. Return 0 if the sub_transaction_set is NULL.

cardano_error_t cardano_sub_transaction_set_get(const cardano_sub_transaction_set_t *sub_transaction_set, size_t index, cardano_sub_transaction_t **element)¶

Retrieves an element from a sub transaction set by index.

This function retrieves the element at the specified index from the provided cardano_sub_transaction_set_t object and stores it in the output parameter. Elements keep the order in which they were decoded or added.

Usage Example:

cardano_sub_transaction_set_t* sub_transaction_set = NULL;
cardano_error_t result = cardano_sub_transaction_set_new(&sub_transaction_set);

// Populate sub_transaction_set with elements

cardano_sub_transaction_t* element = NULL;
result = cardano_sub_transaction_set_get(sub_transaction_set, 2, &element);

if (result == CARDANO_SUCCESS)
{
  // Use the retrieved element
  // Remember to unreference the element once done if it's no longer needed
  cardano_sub_transaction_unref(&element);
}

// Clean up the sub_transaction_set object once done
cardano_sub_transaction_set_unref(&sub_transaction_set);

Parameters:¶

const cardano_sub_transaction_set_t *sub_transaction_set¶: [in] A constant pointer to the cardano_sub_transaction_set_t object from which the element is to be retrieved.
size_t index¶: [in] The index of the element to retrieve from the sub transaction set. Indexing starts at 0.
cardano_sub_transaction_t **element¶: [out] Pointer to a variable where the retrieved element will be stored. This variable will point to the retrieved cardano_sub_transaction_t object. The caller is responsible for managing the lifecycle of the element by calling cardano_sub_transaction_unref when it is no longer needed.

Returns:¶

CARDANO_SUCCESS if the element was successfully retrieved, or an appropriate error code indicating the failure reason.

cardano_error_t cardano_sub_transaction_set_add(cardano_sub_transaction_set_t *sub_transaction_set, cardano_sub_transaction_t *element)¶

Adds an element to a sub transaction set.

This function adds the specified element to the end of the provided cardano_sub_transaction_set_t object. Insertion order is preserved. Two sub transactions with the same id (the blake2b-256 hash of the sub transaction body) are rejected.

Usage Example:

cardano_sub_transaction_set_t* sub_transaction_set = NULL;
cardano_error_t result = cardano_sub_transaction_set_new(&sub_transaction_set);

// Create and initialize a new sub transaction element
cardano_sub_transaction_t* element = { ... };

// Add the element to the sub_transaction_set
result = cardano_sub_transaction_set_add(sub_transaction_set, element);

if (result == CARDANO_SUCCESS)
{
  // Element added successfully
}

// Clean up the sub_transaction_set object once done
cardano_sub_transaction_set_unref(&sub_transaction_set);

Parameters:¶

cardano_sub_transaction_set_t *sub_transaction_set¶: [in] A constant pointer to the cardano_sub_transaction_set_t object to which the element is to be added.
cardano_sub_transaction_t *element¶: [in] Pointer to the cardano_sub_transaction_t object that is to be added to the sub_transaction_set. The element will be referenced by the sub_transaction_set after addition.

Returns:¶

CARDANO_SUCCESS if the element was successfully added to the sub_transaction_set, CARDANO_ERROR_DUPLICATED_KEY if a sub transaction with the same id is already present in the set, or an appropriate error code indicating the failure reason.

cardano_error_t cardano_sub_transaction_set_find_by_id(const cardano_sub_transaction_set_t *sub_transaction_set, const cardano_blake2b_hash_t *id, cardano_sub_transaction_t **element)¶

Finds a sub transaction in the set by its id.

This function searches the provided cardano_sub_transaction_set_t object for the sub transaction whose id (the blake2b-256 hash of the sub transaction body) equals the given hash. The ids are never part of the wire encoding; they are derived from the sub transaction bodies.

Usage Example:

cardano_sub_transaction_set_t* sub_transaction_set = ...; // Assume sub_transaction_set is already initialized
cardano_blake2b_hash_t* id = ...; // Assume id is already initialized

cardano_sub_transaction_t* element = NULL;
cardano_error_t result = cardano_sub_transaction_set_find_by_id(sub_transaction_set, id, &element);

if (result == CARDANO_SUCCESS)
{
  // Use the found sub transaction
  cardano_sub_transaction_unref(&element);
}
else if (result == CARDANO_ERROR_ELEMENT_NOT_FOUND)
{
  printf("No sub transaction with the given id.\n");
}

// Clean up the sub_transaction_set object once done
cardano_sub_transaction_set_unref(&sub_transaction_set);

Parameters:¶

const cardano_sub_transaction_set_t *sub_transaction_set¶: [in] A constant pointer to the cardano_sub_transaction_set_t object to be searched.
const cardano_blake2b_hash_t *id¶: [in] A constant pointer to the cardano_blake2b_hash_t object with the sub transaction id to look up.
cardano_sub_transaction_t **element¶: [out] Pointer to a variable where the found element will be stored. This variable will point to the found cardano_sub_transaction_t object. The caller is responsible for managing the lifecycle of the element by calling cardano_sub_transaction_unref when it is no longer needed.

Returns:¶

CARDANO_SUCCESS if a sub transaction with the given id was found, CARDANO_ERROR_ELEMENT_NOT_FOUND if no sub transaction in the set has the given id, or an appropriate error code indicating the failure reason.

bool cardano_sub_transaction_set_is_tagged(const cardano_sub_transaction_set_t *sub_transaction_set)¶

Determines if the sub transaction set uses tags in its encoding.

This function checks whether the given cardano_sub_transaction_set_t object uses the Conway era encoding for sets, which are collections identified by a tag.

Usage Example:

cardano_sub_transaction_set_t* sub_transaction_set = ...; // Assume sub_transaction_set is already initialized
bool is_tagged_set = cardano_sub_transaction_set_is_tagged(sub_transaction_set);

if (is_tagged_set)
{
  printf("The sub transaction set uses Conway era tag for sets.\n");
}
else
{
  printf("The sub transaction set uses pre-Conway era encoding.\n");
}

Note

This function helps in determining the serialization format of the sub transaction set, which may be necessary for compatibility with other transaction encoders/decoders.

Parameters:¶

const cardano_sub_transaction_set_t *sub_transaction_set¶: [in] A pointer to an initialized cardano_sub_transaction_set_t object.

Returns:¶

A boolean value:

true if the sub transaction set uses the Conway era encoding for sets (tagged sets).
false if the sub transaction set uses the older encoding (arrays without tags).

cardano_error_t cardano_sub_transaction_set_set_use_tag(cardano_sub_transaction_set_t *sub_transaction_set, bool use_tag)¶

Enables or disables tagged encoding (Conway era feature) for the sub transaction set.

This function sets whether the specified cardano_sub_transaction_set_t object should use tagged encoding (introduced in the Conway era) when serializing the set in CBOR. If use_tag is set to true, the set will be encoded using tagged sets. Otherwise, it will use the older array-based encoding method.

Usage Example:

cardano_sub_transaction_set_t* sub_transaction_set = ...; // Assume sub_transaction_set is already initialized
cardano_error_t result = cardano_sub_transaction_set_set_use_tag(sub_transaction_set, true);

if (result == CARDANO_SUCCESS)
{
  printf("The sub transaction set is now set to use tagged encoding.\n");
}
else
{
  printf("Failed to set tagged encoding: %s\n", cardano_error_to_string(result));
}

Parameters:¶

cardano_sub_transaction_set_t *sub_transaction_set¶: [inout] A pointer to an initialized cardano_sub_transaction_set_t object.
bool use_tag¶: [in] A boolean value that determines whether to use tagged encoding (true) or legacy array encoding (false).

Returns:¶

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the operation was successful, or an appropriate error code if an error occurred.

void cardano_sub_transaction_set_unref(cardano_sub_transaction_set_t **sub_transaction_set)¶

Decrements the reference count of a sub_transaction_set object.

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

Usage Example:

cardano_sub_transaction_set_t* sub_transaction_set = NULL;
cardano_error_t result = cardano_sub_transaction_set_new(&sub_transaction_set);

// Perform operations with the sub_transaction_set...

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

Note

After calling cardano_sub_transaction_set_unref, the pointer to the cardano_sub_transaction_set_t object will be set to NULL to prevent its reuse.

Parameters:¶

cardano_sub_transaction_set_t **sub_transaction_set¶: [inout] A pointer to the pointer of the sub_transaction_set 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_sub_transaction_set_ref(cardano_sub_transaction_set_t *sub_transaction_set)¶

Increases the reference count of the cardano_sub_transaction_set_t object.

This function is used to manually increment the reference count of a sub_transaction_set 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_sub_transaction_set_unref.

Usage Example:

// Assuming sub_transaction_set is a previously created sub_transaction_set object

cardano_sub_transaction_set_ref(sub_transaction_set);

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

Note

Always ensure that for every call to cardano_sub_transaction_set_ref there is a corresponding call to cardano_sub_transaction_set_unref to prevent memory leaks.

Parameters:¶

cardano_sub_transaction_set_t *sub_transaction_set¶: A pointer to the sub_transaction_set object whose reference count is to be incremented.

size_t cardano_sub_transaction_set_refcount(const cardano_sub_transaction_set_t *sub_transaction_set)¶

Retrieves the current reference count of the cardano_sub_transaction_set_t object.

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

Usage Example:

// Assuming sub_transaction_set is a previously created sub_transaction_set object

size_t ref_count = cardano_sub_transaction_set_refcount(sub_transaction_set);

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_sub_transaction_set_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_sub_transaction_set_t *sub_transaction_set¶: A pointer to the sub_transaction_set object whose reference count is queried. The object must not be NULL.

Returns:¶

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

void cardano_sub_transaction_set_set_last_error(cardano_sub_transaction_set_t *sub_transaction_set, const char *message)¶

Sets the last error message for a given sub_transaction_set object.

Records an error message in the sub_transaction_set’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_sub_transaction_set_t *sub_transaction_set¶: [in] A pointer to the cardano_sub_transaction_set_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 sub_transaction_set’s last_error is set to an empty string, indicating no error.

const char *cardano_sub_transaction_set_get_last_error(const cardano_sub_transaction_set_t *sub_transaction_set)¶

Retrieves the last error message recorded for a specific sub_transaction_set.

This function returns a pointer to the null-terminated string containing the last error message set by cardano_sub_transaction_set_set_last_error for the given sub_transaction_set. 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_sub_transaction_set_set_last_error for the same sub_transaction_set, or until the sub_transaction_set is deallocated.

Parameters:¶

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

Returns:¶

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