Set the Hook State on another account for a given key, value and namespace

Behaviour

  • Read a 32 byte Hook State key from the kread_ptr
  • Read an arbitrary amount of data from read_ptr (the value)
  • Read a 32 byte Namespace from the nread_ptr
  • Read a 20 byte Account ID from aread_ptr
  • Update the Hook State key on the specified account within the specified namespace with the value
  • But only if a Grant on that account allows this.
  • If the Hook Account is specified in aread_ptr then the behaviour is that of state_set but still allows specification of namespace through nread_ptr

Definition

int64_t state_foreign_set (
    uint32_t read_ptr,
    uint32_t read_len,
    uint32_t kread_ptr,
    uint32_t kread_len,
    uint32_t nread_ptr,
    uint32_t nread_len,
    uint32_t aread_ptr,
    uint32_t aread_len  
);

Example

#define SBUF(str) (uint32_t)(str), sizeof(str)
if (state_foreign_set(SBUF(vault), SBUF(vault_key), SBUF(namespace), SBUF(account)) < 0)
		rollback(SBUF("Error: could not set foreign state!"), 1);

Parameters

NameTypeDescription
read_ptruint32_tPointer to the data (value) to write into Hook State.
If this is 0 (null) then delete the data at this key. May be null.
read_lenuint32_tThe length of the data.
If this is 0 (null) then delete the data at this key. May be null.
kread_ptruint32_tA pointer to the Hook State key at which to store the value.
kread_lenuint32_tThe length of the key. (Should always be 32.)
nread_ptruint32_tA pointer to the namespace which the key belongs to.
nread_lenuint32_tThe length of the namespace. (Should always be 32.)
aread_ptruint32_tA pointer to the Account ID whose state we are trying to modify.
aread_lenuint32_tThe length of the Account ID. (Should always be 20.)

🚧

Caution

XRPL sets internally a maximum hook data size. At time of writing and for public testnet this is hard coded at 128 bytes, however in future it will be a validator-votable number.

Return Code

TypeDescription
int64_tThe number of bytes written to Hook State (the length of the data.)

If negative, an error:
OUT_OF_BOUNDS
- pointers/lengths specified outside of hook memory.

TOO_BIG
- kread_len was greater than 32, or
- read_len was greater than the maximum hook data size.

TOO_SMALL
- kread_len was 0.

NOT_AUTHORIZED
- no appropriate HookGrant was present on the foreign account to allow this state mutation.

PREVIOUS_FAILURE_PREVENTS_RETRY
- during this execution a previous state_foreign_set failed with NOT_AUTHORIZED, and consequently no further calls to this API are allowed during this execution.