Multi Hostname Relay¶

typedef struct cardano_multi_host_name_relay_t cardano_multi_host_name_relay_t¶: This relay points to a multi host name via a DNS (A SRV DNS record) name.

cardano_error_t cardano_multi_host_name_relay_new(const char *dns, size_t str_size, cardano_multi_host_name_relay_t **multi_host_name_relay)¶

Creates and initializes a new cardano_multi_host_name_relay_t object.

This function allocates and initializes a new instance of cardano_multi_host_name_relay_t, which represents a multi-host name relay in the Cardano network. A multi-host name relay provide a DNS name that resolves to multiple IP addresses, facilitating load balancing and failover for stake pool relays.

Usage Example:

const char* dns_name = "relay1.example.com";
cardano_multi_host_name_relay_t* relay = NULL;
cardano_error_t result = cardano_multi_host_name_relay_new(dns_name, strlen(dns_name), &relay);

if (result == CARDANO_SUCCESS)
{
  // Use the multi-host name relay

  // Once done, ensure to clean up and release the relay
  cardano_multi_host_name_relay_unref(&relay);
}
else
{
  printf("Failed to create multi-host name relay: %s\n", dns_name);
}

Parameters:¶

const char *dns¶: [in] A pointer to a character array containing the DNS name for the multi-host relay.
size_t str_size¶: [in] The length of the DNS string.
cardano_multi_host_name_relay_t **multi_host_name_relay¶: [out] On successful initialization, this will point to the newly created cardano_multi_host_name_relay_t object. This object represents a “strong reference” to the multi-host name relay, meaning that it is fully initialized and ready for use. The caller is responsible for managing the lifecycle of this object. Specifically, once the multi-host name relay is no longer needed, the caller must release it by calling cardano_multi_host_name_relay_unref.

Returns:¶

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the multi-host name relay was successfully created, or an appropriate error code indicating the failure reason, such as invalid DNS name format or out of memory errors.

cardano_error_t cardano_multi_host_name_relay_from_cbor(cardano_cbor_reader_t *reader, cardano_multi_host_name_relay_t **multi_host_name_relay)¶

Creates a cardano_multi_host_name_relay_t from a CBOR reader.

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

Usage Example:

cardano_cbor_reader_t* reader = cardano_cbor_reader_new(cbor_data, data_size);
cardano_multi_host_name_relay_t* multi_host_name_relay = NULL;

cardano_error_t result = cardano_multi_host_name_relay_from_cbor(reader, &multi_host_name_relay);

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

  // Once done, ensure to clean up and release the multi_host_name_relay
  cardano_multi_host_name_relay_unref(&multi_host_name_relay);
}
else
{
  const char* error = cardano_cbor_reader_get_last_error(reader);
  printf("Failed to decode multi_host_name_relay: %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_multi_host_name_relay_t object by calling cardano_multi_host_name_relay_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_multi_host_name_relay_t **multi_host_name_relay¶: [out] A pointer to a pointer of cardano_multi_host_name_relay_t that will be set to the address of the newly created multi_host_name_relay 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_multi_host_name_relay_to_cbor(const cardano_multi_host_name_relay_t *multi_host_name_relay, cardano_cbor_writer_t *writer)¶

Serializes protocol version into CBOR format using a CBOR writer.

This function serializes the given cardano_multi_host_name_relay_t object using a cardano_cbor_writer_t.

Usage Example:

cardano_multi_host_name_relay_t* multi_host_name_relay = ...;
cardano_cbor_writer_t* writer = cardano_cbor_writer_new();

if (writer)
{
  cardano_error_t result = cardano_multi_host_name_relay_to_cbor(multi_host_name_relay, 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_multi_host_name_relay_unref(&multi_host_name_relay);

Parameters:¶

const cardano_multi_host_name_relay_t *multi_host_name_relay¶: [in] A constant pointer to the cardano_multi_host_name_relay_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 multi_host_name_relay or writer is NULL, returns CARDANO_ERROR_POINTER_IS_NULL.

cardano_error_t cardano_multi_host_name_relay_to_cip116_json(const cardano_multi_host_name_relay_t *relay, cardano_json_writer_t *writer)¶

Serializes a multi-host name relay to CIP-116 JSON.

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

Parameters:¶

const cardano_multi_host_name_relay_t *relay¶: [in] Pointer to a valid cardano_multi_host_name_relay_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 relay or writer is NULL. Other Any error propagated from nested writers.

size_t cardano_multi_host_name_relay_get_dns_size(const cardano_multi_host_name_relay_t *multi_host_name_relay)¶

Retrieves the size of the DNS name string of a cardano_multi_host_name_relay_t object.

This function returns the size in bytes of the DNS name string stored within a cardano_multi_host_name_relay_t object. This size includes the null-terminating character for the string, thus providing the actual length of the DNS name plus one.

Usage Example:

cardano_multi_host_name_relay_t* relay = ...; // Assume relay is already initialized
size_t dns_size = cardano_multi_host_name_relay_get_dns_size(relay);
printf("Size of the DNS name string: %zu bytes\n", dns_size);

Note

This function returns 0 if the multi_host_name_relay pointer is NULL.

Parameters:¶

const cardano_multi_host_name_relay_t *multi_host_name_relay¶: [in] A constant pointer to an initialized cardano_multi_host_name_relay_t object.

Returns:¶

The size in bytes of the DNS name string, including the null terminator. If the input pointer is NULL, returns 0 to indicate an error or uninitialized relay object.

const char *cardano_multi_host_name_relay_get_dns(const cardano_multi_host_name_relay_t *multi_host_name_relay)¶

Retrieves the DNS name string from a cardano_multi_host_name_relay_t object.

This function provides access to the DNS name string contained within a cardano_multi_host_name_relay_t object. The string represents the domain name used for DNS-based relay discovery and connection in the Cardano network.

Usage Example:

cardano_multi_host_name_relay_t* relay = ...; // Assume relay is already initialized
const char* dns_name = cardano_multi_host_name_relay_get_dns(relay);

if (dns_name != NULL)
{
  printf("DNS Name: %s\n", dns_name);
}
else
{
  printf("Failed to retrieve DNS name.\n");
}

Note

This function returns NULL if the multi_host_name_relay pointer is NULL, indicating either an error or an uninitialized state.

Parameters:¶

const cardano_multi_host_name_relay_t *multi_host_name_relay¶: [in] A constant pointer to an initialized cardano_multi_host_name_relay_t object.

Returns:¶

A constant pointer to a null-terminated string representing the DNS name. If the input pointer is NULL, returns NULL to indicate an error or uninitialized relay object. The returned string points to internal memory within the cardano_multi_host_name_relay_t object and must not be modified or freed by the caller. The memory will remain valid as long as the cardano_multi_host_name_relay_t object is not destroyed.

cardano_error_t cardano_multi_host_name_relay_set_dns(const char *dns, size_t dns_size, cardano_multi_host_name_relay_t *multi_host_name_relay)¶

Sets the DNS name for a cardano_multi_host_name_relay_t object.

This function updates the DNS name in a cardano_multi_host_name_relay_t object with the provided DNS name string. The DNS name is used for DNS-based relay discovery and connection in the Cardano network. The function ensures the new DNS name is properly stored within the relay object, replacing any previous value.

Usage Example:

cardano_multi_host_name_relay_t* relay = ...; // Assume relay is already initialized
const char* new_dns = "new.example.com";
size_t dns_size = strlen(new_dns);
cardano_error_t result = cardano_multi_host_name_relay_set_dns(new_dns, dns_size, relay);

if (result == CARDANO_SUCCESS)
{
  printf("DNS name updated successfully.\n");
}
else
{
  printf("Failed to update DNS name.\n");
}

Note

This function does not take ownership of the dns string; the caller must ensure it remains valid for the duration of the call and manages its memory appropriately.

Parameters:¶

const char *dns¶: [in] A constant pointer to a character array containing the new DNS name in null-terminated string format.
size_t dns_size¶: [in] The size of the DNS name string, excluding the null terminator.
cardano_multi_host_name_relay_t *multi_host_name_relay¶: [out] A pointer to an initialized cardano_multi_host_name_relay_t object which will receive the updated DNS name.

Returns:¶

cardano_error_t indicating the outcome of the operation. Returns CARDANO_SUCCESS if the DNS name was successfully updated, or an appropriate error code indicating the failure reason, such as invalid format, null pointers, or out of memory errors.

void cardano_multi_host_name_relay_unref(cardano_multi_host_name_relay_t **multi_host_name_relay)¶

Decrements the reference count of a cardano_multi_host_name_relay_t object.

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

Usage Example:

cardano_multi_host_name_relay_t* multi_host_name_relay = cardano_multi_host_name_relay_new(major, minor);

// Perform operations with the multi_host_name_relay...

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

Note

After calling cardano_multi_host_name_relay_unref, the pointer to the cardano_multi_host_name_relay_t object will be set to NULL to prevent its reuse.

Parameters:¶

cardano_multi_host_name_relay_t **multi_host_name_relay¶: [inout] A pointer to the pointer of the multi_host_name_relay 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_multi_host_name_relay_ref(cardano_multi_host_name_relay_t *multi_host_name_relay)¶

Increases the reference count of the cardano_multi_host_name_relay_t object.

This function is used to manually increment the reference count of an cardano_multi_host_name_relay_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_multi_host_name_relay_unref.

Usage Example:

// Assuming multi_host_name_relay is a previously created multi_host_name_relay object

cardano_multi_host_name_relay_ref(multi_host_name_relay);

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

Note

Always ensure that for every call to cardano_multi_host_name_relay_ref there is a corresponding call to cardano_multi_host_name_relay_unref to prevent memory leaks.

Parameters:¶

cardano_multi_host_name_relay_t *multi_host_name_relay¶: A pointer to the cardano_multi_host_name_relay_t object whose reference count is to be incremented.

size_t cardano_multi_host_name_relay_refcount(const cardano_multi_host_name_relay_t *multi_host_name_relay)¶

Retrieves the current reference count of the cardano_multi_host_name_relay_t object.

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

Usage Example:

// Assuming multi_host_name_relay is a previously created multi_host_name_relay object

size_t ref_count = cardano_multi_host_name_relay_refcount(multi_host_name_relay);

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_multi_host_name_relay_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_multi_host_name_relay_t *multi_host_name_relay¶: A pointer to the cardano_multi_host_name_relay_t object whose reference count is queried. The object must not be NULL.

Returns:¶

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

void cardano_multi_host_name_relay_set_last_error(cardano_multi_host_name_relay_t *multi_host_name_relay, const char *message)¶

Sets the last error message for a given cardano_multi_host_name_relay_t object.

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

const char *cardano_multi_host_name_relay_get_last_error(const cardano_multi_host_name_relay_t *multi_host_name_relay)¶

Retrieves the last error message recorded for a specific multi_host_name_relay.

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

Parameters:¶

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

Returns:¶

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