nupp.checksum.spi

Implementation interfaces for nupp.checksum algorithm catalogs.

The facade chooses the unique highest priority during module initialization. Importing this declaration does not load storage or algorithms. A provider supplies an algorithms map keyed by canonical algorithm name. Each descriptor's name agrees with its key, and each create returns independent owned state. The chosen catalog replaces matching built-in algorithms and may add names; other built-in algorithms remain available. Empty discovery uses the built-in catalog. Discovery order never selects a provider.

The facade validates and retains descriptors while requiring the module. Lookup, listing, and context creation then use cached descriptors without SPI resolution. Provider state processes chunks incrementally and retains neither input nor output spans. Cleanup consumes state without suspension. Reuse these canonical State and Algorithm identities, including ownership and borrowing signatures. value returns a non-consuming uint64 snapshot; width specifies its meaningful bits from 1 through 64. Standard names retain their standard widths and exact CRC parameters. Checksums detect corruption and provide no authentication.

interface Algorithm ...

name: string

width: integer

create: function(self: Algorithm): State

interface Provider ...

priority: integer?

algorithms: {[string]: Algorithm}

interface State is nupp.Closeable ...

close: @nosuspend function(takes self: State): nil

update: function(exclusive self: State, borrows bytes: ByteSpan): nil

value: function(self: State): uint64