WASM Host Functions

WASM Host Functions Reference

Host functions available to Core Mods (WASM).

Functions

Function	Parameters	Returns	Description
host_get_inventory_slot	_caller: Caller<'_, ModState>, entity_id: u64, slot: u32	Upper 32 bits: item_id, Lower 32 bits: count (0 = empty slot)	Get inventory slot contents
host_get_machine_state	_caller: Caller<'_, ModState>, entity_id: u64	- 0: Idle	Get machine state by entity ID
host_log_error	mut caller: Caller<'_, ModState>, ptr: u32, len: u32	Nothing (void function)	Log an error message from WASM mod
host_log_info	mut caller: Caller<'_, ModState>, ptr: u32, len: u32	Nothing (void function)	Log an info message from WASM mod
host_set_machine_enabled	_caller: Caller<'_, ModState>, entity_id: u64, enabled: i32	- 0: Success	Enable or disable a machine
host_subscribe_event	_caller: Caller<'_, ModState>, event_type: u32	Subscription ID (>= 0 on success, negative on error)	Subscribe to game events

Details

host_get_inventory_slot

Get inventory slot contents

Parameters:

• _caller: Caller<'_
• ModState>
• entity_id: u64
• slot: u32

Returns: Upper 32 bits: item_id, Lower 32 bits: count (0 = empty slot)

host_get_machine_state

Get machine state by entity ID

Parameters:

• _caller: Caller<'_
• ModState>
• entity_id: u64

Returns:

• 0: Idle
• 1: Processing
• 2: Waiting for input
• -1: Error (entity not found)

host_log_error

Log an error message from WASM mod

Parameters:

• mut caller: Caller<'_
• ModState>
• ptr: u32
• len: u32

Returns: Nothing (void function)

host_log_info

Log an info message from WASM mod

Parameters:

• mut caller: Caller<'_
• ModState>
• ptr: u32
• len: u32

Returns: Nothing (void function)

host_set_machine_enabled

Enable or disable a machine

Parameters:

• _caller: Caller<'_
• ModState>
• entity_id: u64
• enabled: i32

Returns:

• 0: Success
• -1: Entity not found
• -2: Permission denied

host_subscribe_event

Subscribe to game events

Parameters:

• _caller: Caller<'_
• ModState>
• event_type: u32

Returns: Subscription ID (>= 0 on success, negative on error)