Link: order the streams of an attachment by bind sequence - #358
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The serve peer assigns each bound stream a sequence under its tracking lock, before it answers Bound, and passes it to the service handler. A stream bound later gets a larger sequence however late its handler runs, so a service can fence a stream's successor by bind order. Handlers that need no order ignore it.
TestBindSequence opens two streams of one attachment, lets the later one's handler report first, reconnects the serve peer and opens a third; the sequences the handlers saw must increase strictly from above zero. The ServiceHandler comment and the Link guide define bind order as the order of assignment under the serve peer's tracking lock, which concurrent Bound and Opened replies need not follow, and scope the sequence to one Serve call: it survives reconnects and increases strictly, with gaps.
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Link protocol change, split out of the File protocol fixes (plan row 6a, L1c) so that it gets its own review.
What changes
sandboxlink.ServiceHandler.Servenow also receives a bind sequence:func(ctx, Bind, seq uint64, Stream).track's lock, before it answersBound. A stream of an attachment that binds later therefore gets a larger sequence, however late its handler runs.docs/sandbox-link-protocol.md§ "Implement a serve peer" states that order. A service may rely on it to fence the succession of an attachment's streams.Why
The File protocol's stream succession fence admits one stream per attachment at a time. Without this change, its order would come from when each handler reaches the File server, which can differ from bind order. This PR only adds the sequence; the File protocol PR that follows uses it.
Callers
sandboxio, the File and Process handlers accept and ignore it, so the File protocol is unchanged at this commit.Checks
go build ./...go vet ./internal/sandboxlink/... ./apps/sandboxio/... ./apps/daemon/...go test -race -count=1 ./internal/sandboxlink/... ./apps/sandboxio/... ./apps/daemon/internal/gateway/GOOS=darwinandGOOS=windowsbuilds of./internal/sandboxlink/... ./apps/daemon/...Need help on this PR? Tag
@codesmith-botwith what you need. Autofix is disabled.