state_foreign_set

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

C

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

C

#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

Name	Type	Description
read_ptr	uint32_t	Pointer 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_len	uint32_t	The length of the data. If this is 0 (null) then delete the data at this key. May be null.
kread_ptr	uint32_t	A pointer to the Hook State key at which to store the value.
kread_len	uint32_t	The length of the key. (Should always be 32.)
nread_ptr	uint32_t	A pointer to the namespace which the key belongs to.
nread_len	uint32_t	The length of the namespace. (Should always be 32.)
aread_ptr	uint32_t	A pointer to the Account ID whose state we are trying to modify.
aread_len	uint32_t	The 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

Type

Description

int64_t

The 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.