Asset ID

typedef struct cardano_asset_id_t cardano_asset_id_t

Represents an asset identifier in the Cardano blockchain.

The cardano_asset_id_t structure encapsulates the unique identification of a native asset on the Cardano blockchain. Each asset is uniquely identified by a combination of its policy ID and asset name.

cardano_error_t cardano_asset_id_new(cardano_blake2b_hash_t *policy_id, cardano_asset_name_t *asset_name, cardano_asset_id_t **asset_id)

Creates and initializes a new instance of a Cardano asset identifier.

This function allocates and initializes a new instance of a cardano_asset_id_t object, which represents a unique asset identifier in the Cardano blockchain. The asset ID is composed of a policy ID and an asset name.

  • Policy ID: A cryptographic hash (Blake2b hash) that identifies the minting policy.

  • Asset Name: A user-defined name (max 32 bytes) associated with the asset.

The function ensures that a valid asset identifier is created by linking the provided policy ID and asset name.

Usage Example: 

cardano_blake2b_hash_t* policy_id = ...; // Assume policy ID is initialized
cardano_asset_name_t* asset_name = ...;  // Assume asset name is initialized
cardano_asset_id_t* asset_id = NULL;

// Create a new asset ID
cardano_error_t result = cardano_asset_id_new(policy_id, asset_name, &asset_id);

if (result == CARDANO_SUCCESS)
{
  // Use the asset ID

  // Once done, release the asset ID
  cardano_asset_id_unref(&asset_id);
}
else
{
  printf("Failed to create asset ID: %s\n", cardano_error_to_string(result));
}

Parameters:
cardano_blake2b_hash_t *policy_id

[in] A pointer to an initialized cardano_blake2b_hash_t object representing the minting policy ID. This value must not be NULL.

cardano_asset_name_t *asset_name

[in] A pointer to an initialized cardano_asset_name_t object representing the name of the asset. This value must not be NULL.

cardano_asset_id_t **asset_id

[out] On successful creation, this will point to a newly created cardano_asset_id_t object representing the asset. The caller is responsible for managing the lifecycle of this object by calling cardano_asset_id_unref when it is no longer needed.

Returns:

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the asset ID was successfully created, or an appropriate error code indicating the failure reason, such as:

cardano_error_t cardano_asset_id_new_lovelace(cardano_asset_id_t **asset_id)

Creates a new instance of the Cardano native asset identifier for Lovelace.

This function allocates and initializes a new instance of a cardano_asset_id_t object that represents the Cardano native coin, Lovelace. Lovelace is the smallest denomination of the ADA cryptocurrency, and it does not have an associated asset name or a policy ID like other assets. Instead, Lovelace is identified by the special identifier “lovelace.”

Usage Example: 

cardano_asset_id_t* lovelace_asset_id = NULL;

// Create a new asset ID for Lovelace
cardano_error_t result = cardano_asset_id_new_lovelace(&lovelace_asset_id);

if (result == CARDANO_SUCCESS)
{
  // Use the Lovelace asset ID

  // Once done, release the asset ID
  cardano_asset_id_unref(&lovelace_asset_id);
}
else
{
  printf("Failed to create Lovelace asset ID: %s\n", cardano_error_to_string(result));
}

Parameters:
cardano_asset_id_t **asset_id

[out] On successful creation, this will point to a newly created cardano_asset_id_t object representing the Lovelace asset. The caller is responsible for managing the lifecycle of this object and must release it by calling cardano_asset_id_unref when it is no longer needed.

Returns:

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the Lovelace asset ID was successfully created, or an appropriate error code indicating the failure reason, such as:

cardano_error_t cardano_asset_id_from_bytes(const byte_t *data, size_t size, cardano_asset_id_t **asset_id)

Creates and initializes a new instance of a Cardano asset ID from byte data.

This function allocates and initializes a new instance of a cardano_asset_id_t object, which represents a Cardano native asset. The asset ID is formed by concatenating the bytes of the policy ID and the asset name. The asset name can be an empty byte sequence, but the policy ID must always be present.

Usage Example: 

const byte_t* asset_data = ...; // Asset data should contain policy ID followed by asset name
size_t asset_size = ...; // Size of asset_data (minimum 28 bytes)
cardano_asset_id_t* asset_id = NULL;

cardano_error_t result = cardano_asset_id_from_bytes(asset_data, asset_size, &asset_id);
if (result == CARDANO_SUCCESS)
{
  // Use the asset_id
  // Once done, ensure to clean up and release the asset_id
  cardano_asset_id_unref(&asset_id);
}
else
{
  printf("Failed to create asset ID: %s\n", cardano_error_to_string(result));
}

Note

The byte data must include the policy ID followed by the asset name, which could be empty.

Parameters:
const byte_t *data

[in] A pointer to an array of bytes representing the concatenation of the policy ID and the asset name. The policy ID typically occupies the first 28 bytes, followed by the bytes of the asset name. The data pointer must not be NULL.

size_t size

[in] The size of the byte array, which includes both the policy ID and the asset name. The size must be at least 28 bytes (the size of the policy ID), but it can be larger depending on the length of the asset name.

cardano_asset_id_t **asset_id

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

Returns:

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the asset ID was successfully created from the provided bytes, or an appropriate error code indicating the failure reason, such as CARDANO_ERROR_POINTER_IS_NULL if the input data pointer is NULL, or CARDANO_ERROR_INVALID_ARGUMENT if the size is less than 28 bytes or violates other constraints.

cardano_error_t cardano_asset_id_from_hex(const char *hex_string, size_t size, cardano_asset_id_t **asset_id)

Creates and initializes a new instance of a Cardano asset ID from a hexadecimal string.

This function allocates and initializes a new instance of a cardano_asset_id_t object, which represents the ID of a Cardano native asset. The asset ID is derived from a hexadecimal-encoded string, typically representing a policy ID or asset name in hexadecimal format.

Usage Example: 

const char* hex_string = "616263646566..."; // Hexadecimal representation of some asset data
size_t hex_size = strlen(hex_string); // Size of the hexadecimal string
cardano_asset_id_t* asset_id = NULL;

cardano_error_t result = cardano_asset_id_from_hex(hex_string, hex_size, &asset_id);

if (result == CARDANO_SUCCESS)
{
  // Use the asset_id
  // Once done, ensure to clean up and release the asset_id
  cardano_asset_id_unref(&asset_id);
}
else
{
  printf("Failed to create asset ID from hex: %s\n", cardano_error_to_string(result));
}

Parameters:
const char *hex_string

[in] A pointer to a null-terminated string containing the asset ID in hexadecimal format. The string must only contain valid hexadecimal characters (0-9, a-f, A-F) and must not be NULL.

size_t size

[in] The size of the hexadecimal string, not including the null terminator. This allows for flexible string lengths while excluding the null terminator from the conversion process.

cardano_asset_id_t **asset_id

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

Returns:

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the asset ID was successfully created from the provided hexadecimal string, or an appropriate error code indicating the failure reason, such as CARDANO_ERROR_POINTER_IS_NULL if the input string pointer is NULL, or CARDANO_ERROR_INVALID_ARGUMENT if the string contains invalid characters or does not meet other constraints.

const byte_t *cardano_asset_id_get_bytes(const cardano_asset_id_t *asset_id)

Retrieves the byte representation of a Cardano asset id.

This function provides access to the underlying byte array of a cardano_asset_id_t object. The byte array represents the asset id as it is stored and used within the Cardano ecosystem.

Usage Example: 

cardano_asset_id_t* asset_id = ...; // Assume asset_id is already initialized
const byte_t* name_bytes = cardano_asset_id_get_bytes(asset_id);

if (name_bytes != NULL)
{
  // Process the bytes of the asset id
  // Note: The length of the byte array should be known or determined separately
}
else
{
  printf("Failed to retrieve the bytes of the asset id.\n");
}

Parameters:
const cardano_asset_id_t *asset_id

[in] A pointer of an initialized cardano_asset_id_t object. The pointer must not be NULL and should point to a valid asset id object.

Returns:

A pointer to the constant byte array representing the asset id. This pointer points to an internal buffer and must not be modified or freed by the caller. If the input is NULL or an error occurs, the function returns NULL.

size_t cardano_asset_id_get_bytes_size(const cardano_asset_id_t *asset_id)

Retrieves the size of the byte array for a Cardano asset id.

This function returns the size of the byte array representing the asset id contained within a cardano_asset_id_t object.

Usage Example: 

cardano_asset_id_t* asset_id = ...; // Assume asset_id is already initialized
size_t name_size = cardano_asset_id_get_bytes_size(asset_id);

if (name_size > 0)
{
  const byte_t* name_bytes = cardano_asset_id_get_bytes(asset_id);
  // Process the bytes knowing the exact size of the asset id
}
else
{
  printf("Failed to retrieve the size of the asset id or asset id is empty.\n");
}

Parameters:
const cardano_asset_id_t *asset_id

[in] A pointer of an initialized cardano_asset_id_t object. The pointer must not be NULL and should point to a valid asset id object.

Returns:

The size of the byte array representing the asset id. If the input is NULL or an error occurs, the function returns 0. This size does not include a null terminator, as asset ids can contain arbitrary binary data.

const char *cardano_asset_id_get_hex(const cardano_asset_id_t *asset_id)

Retrieves the hexadecimal string representation of a Cardano asset ID.

This function returns the hexadecimal string representation of a cardano_asset_id_t object. The string encodes the asset ID, which consists of the concatenated bytes of the policy ID and asset name.

Usage Example: 

const cardano_asset_id_t* asset_id = ...; // Assume asset_id is already initialized
const char* hex_string = cardano_asset_id_get_hex(asset_id);

if (hex_string != NULL)
{
  // Process the hexadecimal string of the asset ID
  printf("Asset ID in hex: %s\n", hex_string);
}
else
{
  printf("Failed to retrieve the hexadecimal string of the asset ID.\n");
}

Parameters:
const cardano_asset_id_t *asset_id

[in] A pointer to an initialized cardano_asset_id_t object. The pointer must not be NULL and should point to a valid asset ID object.

Returns:

A pointer to a null-terminated string representing the asset ID in hexadecimal format. This string is owned by the cardano_asset_id_t object and must not be modified or freed by the caller. If the input is NULL or an error occurs, the function returns NULL.

size_t cardano_asset_id_get_hex_size(const cardano_asset_id_t *asset_id)

Retrieves the size of the hexadecimal string for a Cardano asset ID.

This function returns the size of the hexadecimal string representation of a cardano_asset_id_t object. The size includes the number of characters in the hexadecimal string, not including the null terminator.

Usage Example: 

const cardano_asset_id_t* asset_id = ...; // Assume asset_id is already initialized
size_t hex_size = cardano_asset_id_get_hex_size(asset_id);

if (hex_size > 0)
{
  const char* hex_string = cardano_asset_id_get_hex(asset_id);
  // Process the hex string knowing the exact size of the asset ID
  printf("Hexadecimal string size: %zu\n", hex_size);
}
else
{
  printf("Failed to retrieve the size of the asset ID in hex or asset ID is empty.\n");
}

Parameters:
const cardano_asset_id_t *asset_id

[in] A pointer to an initialized cardano_asset_id_t object. The pointer must not be NULL and should point to a valid asset ID object.

Returns:

The size of the hexadecimal string representing the asset ID. If the input is NULL or an error occurs, the function returns 0. The size does not include a null terminator.

bool cardano_asset_id_is_lovelace(const cardano_asset_id_t *asset_id)

Checks if the given asset ID represents the native Cardano currency, Lovelace.

This function determines if a cardano_asset_id_t object corresponds to the Lovelace currency. Lovelace is the smallest unit of ADA, the native cryptocurrency of the Cardano network. A Lovelace asset ID is identified by the absence of an asset name and a specific policy ID.

Usage Example: 

const cardano_asset_id_t* asset_id = ...; // Assume asset_id is already initialized
bool is_lovelace = cardano_asset_id_is_lovelace(asset_id);

if (is_lovelace)
{
  printf("The asset is Lovelace.\n");
}
else
{
  printf("The asset is not Lovelace.\n");
}

Parameters:
const cardano_asset_id_t *asset_id

[in] A constant pointer to an initialized cardano_asset_id_t object.

Returns:

true if the asset ID represents Lovelace, or false otherwise. If the input asset_id is NULL, the function returns false.

cardano_blake2b_hash_t *cardano_asset_id_get_policy_id(cardano_asset_id_t *asset_id)

Retrieves the policy ID from a Cardano asset ID.

This function extracts the policy ID from a given cardano_asset_id_t object. The policy ID is a cardano_blake2b_hash_t object representing the unique identifier of the policy under which the asset was issued.

Usage Example: 

cardano_asset_id_t* asset_id = ...; // Assume asset_id is already initialized
if (!cardano_asset_id_is_lovelace(asset_id))
{
  cardano_blake2b_hash_t* policy_id = cardano_asset_id_get_policy_id(asset_id);

  if (policy_id != NULL)
  {
    // Use the policy ID
    // Ensure to release the policy ID once done
    cardano_blake2b_hash_unref(&policy_id);
  }
  else
  {
    printf("Failed to retrieve the policy ID or asset_id is NULL.\n");
  }
}
else
{
  printf("This asset is Lovelace and has no policy ID.\n");
}

Note

For assets that represent the native currency Lovelace, there is no associated policy ID. Clients must first call cardano_asset_id_is_lovelace to check if the asset is Lovelace before attempting to retrieve the policy ID. If the asset is Lovelace, this function will return NULL.

Parameters:
cardano_asset_id_t *asset_id

[in] A pointer to an initialized cardano_asset_id_t object.

Returns:

A pointer to the cardano_blake2b_hash_t object representing the policy ID. The returned policy ID is a new reference, and the caller is responsible for releasing it with cardano_blake2b_hash_unref when it is no longer needed. If the asset ID is NULL, or if the asset represents Lovelace, the function returns NULL.

cardano_asset_name_t *cardano_asset_id_get_asset_name(cardano_asset_id_t *asset_id)

Retrieves the asset name from a Cardano asset ID.

This function extracts the asset name from a given cardano_asset_id_t object. The asset name is a cardano_asset_name_t object representing the name of the asset within the specified policy.

Usage Example: 

cardano_asset_id_t* asset_id = ...; // Assume asset_id is already initialized

if (!cardano_asset_id_is_lovelace(asset_id))
{
  cardano_asset_name_t* asset_name = cardano_asset_id_get_asset_name(asset_id);

  if (asset_name != NULL)
  {
    // Use the asset name
    // Ensure to release the asset name once done
    cardano_asset_name_unref(&asset_name);
  }
  else
  {
    printf("Failed to retrieve the asset name or asset_id is NULL.\n");
  }
}
else
{
  printf("This asset is Lovelace and has no asset name.\n");
}

Note

For assets that represent the native currency Lovelace, there is no associated asset name. Clients must first call cardano_asset_id_is_lovelace to check if the asset is Lovelace before attempting to retrieve the asset name. If the asset is Lovelace, this function will return NULL.

Parameters:
cardano_asset_id_t *asset_id

[in] A pointer to an initialized cardano_asset_id_t object.

Returns:

A pointer to the cardano_asset_name_t object representing the asset name. The returned asset name is a new reference, and the caller is responsible for releasing it with cardano_asset_name_unref when it is no longer needed. If the asset ID is NULL or if the asset represents Lovelace, the function returns NULL.

void cardano_asset_id_unref(cardano_asset_id_t **asset_id)

Decrements the reference count of a cardano_asset_id_t object.

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

Usage Example: 

cardano_asset_id_t* asset_id = cardano_asset_id_new(major, minor);

// Perform operations with the asset_id...

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

Note

After calling cardano_asset_id_unref, the pointer to the cardano_asset_id_t object will be set to NULL to prevent its reuse.

Parameters:
cardano_asset_id_t **asset_id

[inout] A pointer to the pointer of the asset_id 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_asset_id_ref(cardano_asset_id_t *asset_id)

Increases the reference count of the cardano_asset_id_t object.

This function is used to manually increment the reference count of an cardano_asset_id_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_asset_id_unref.

Usage Example: 

// Assuming asset_id is a previously created asset_id object

cardano_asset_id_ref(asset_id);

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

Note

Always ensure that for every call to cardano_asset_id_ref there is a corresponding call to cardano_asset_id_unref to prevent memory leaks.

Parameters:
cardano_asset_id_t *asset_id

A pointer to the cardano_asset_id_t object whose reference count is to be incremented.

size_t cardano_asset_id_refcount(const cardano_asset_id_t *asset_id)

Retrieves the current reference count of the cardano_asset_id_t object.

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

Usage Example: 

// Assuming asset_id is a previously created asset_id object

size_t ref_count = cardano_asset_id_refcount(asset_id);

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_asset_id_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_asset_id_t *asset_id

A pointer to the cardano_asset_id_t object whose reference count is queried. The object must not be NULL.

Returns:

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

void cardano_asset_id_set_last_error(cardano_asset_id_t *asset_id, const char *message)

Sets the last error message for a given cardano_asset_id_t object.

Records an error message in the asset_id’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_asset_id_t *asset_id

[in] A pointer to the cardano_asset_id_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 asset_id’s last_error is set to an empty string, indicating no error.

const char *cardano_asset_id_get_last_error(const cardano_asset_id_t *asset_id)

Retrieves the last error message recorded for a specific asset_id.

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

Parameters:
const cardano_asset_id_t *asset_id

[in] A pointer to the cardano_asset_id_t instance whose last error message is to be retrieved. If the asset_id is NULL, the function returns a generic error message indicating the null asset_id.

Returns:

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