Module slot 

Byte-string keys and slot addressing.

Key is the byte-string key type used across the cap model: it names one slot in a single cnode (a slot key), and it also keys the kernel’s resource tables (a meter key / quota key — same type, unrelated meaning; see the kernel-assisted Gas/Quota handles). A SlotPath walks from the root cnode through nested Cap::CNode slots down to a target slot.

A cnode is a sparse direct map keyed by logical byte strings, not an integer-indexed array — so a slot name is a Key (a short byte string), and a path is a SlotPath (a sequence of Keys). There is no fixed slot count: a cnode is bounded by storage quota, not a compile-time capacity. The V1 ABI uses single-byte keys (Key::from(b)), but the type admits arbitrary-length keys for future ABI extensions (e.g. address -> Cap::Instance).

Structs

ArchivedKey

An archived Key

ArchivedSlotPath

An archived SlotPath

Key

The logical key naming one slot in a single cnode.

KeyResolver

The resolver for an archived Key

SlotPath

Path from the root cnode through nested cnodes to a slot.

SlotPathResolver

The resolver for an archived SlotPath

Constants

MAX_KEY_LEN

Inline byte capacity of a Key. Keys longer than this spill to the heap — there is no hard cap (unlike a fixed array). The V1 ABI uses 1-byte keys; 8 bytes inline covers an address-sized key without allocating.

Functions

key_from_regs

Reconstruct a Key from the (packed, len) register pair produced by key_to_regs. A len > 8 is clamped to 8 (defensive; key_to_regs never emits one).

key_to_regs

Pack a Key (≤ MAX_KEY_LEN bytes) into two registers for storage in a kernel-assisted unit handle (Gas{meter_key} / Quota{quota_key}): the key bytes little-endian-packed into the first register, the byte length into the second. Inverse of key_from_regs.