Artifact [e7e65bd8ee]

Artifact e7e65bd8ee988d7fdf5bb364317c1bbe1f63a9ee6a952fead2c7f8133d265936:

• File repo_submanifest.go — part of check-in [05a53c393d] at 2026-10-19 21:50:52 on branch feat/submanifest-reader — fix(sync): gate sub-manifest trees on the send-submanifests pragma

  draft-fossil-submanifests-00 §7.2 no longer gates S-bearing artifacts on the peer's announced version: fossil 2.29 announces 22900 and reads no tree. A peer that reads trees now says so with pragma send-submanifests, which go-libfossil sends in every request right after client-version and in every reply, clone replies included, right after server-version, whatever the sub-manifest settings. The version threshold and the 22900 reader marker are gone; client-version and server-version announce 22800, the fossil release whose protocol this library speaks.

  A tree manifest or sub-manifest is refused to a peer that has not sent the pragma with "Peer does not accept sub-manifests.", never converted or omitted. A server decides from the whole request it answers, a client from the replies it has received in the exchange. avoid-submanifests moves from the ci-lock answer into the same leading run of every reply.

  Enabling emission over a stored submanifest-k outside 1 to 12 without an explicit k is refused, naming the stored value (§8.1).

  The conformance suite pins the draft with the 2026-10-19 errata applied: SM-7.2-1 and SM-6.3-3 are met rather than deviations, SM-7.2-2, SM-7.2-3, SM-6.3-1/2/7 and SM-8.1-3 follow the corrected text, and SM-7.2-4 covers the pragma's placement. The zit interop pushes a tree go-libfossil wrote to zit and checks both sides refuse trees when the pragma is stripped.

  Tracked in #452. (user: [email protected], size: 3127) [annotate] [blame] [check-ins using] [more...]

package libfossil

import (
	"errors"
	"fmt"

	fsltype "github.com/danmestas/go-libfossil/internal/fsltype"
	"github.com/danmestas/go-libfossil/internal/manifest"
)

// EnableSubmanifests turns on tree manifest emission
// (draft-fossil-submanifests-00 §8.1): from the next commit, check-ins carry
// their file sets as sub-manifest trees. k is the partition parameter, 1 to
// 12, or 0 to select one. A valid pinned k is kept, and an explicit k that
// differs from it is refused: changing it is RetuneSubmanifests. A stored k
// outside 1..12 is no valid pin: an explicit k replaces it, and k = 0 is
// refused, naming the stored value. With no stored k, an explicit k is
// pinned, or one is selected as zit selects it:
// the §6.3 cost over one check-in's file set, refined by replaying recent
// history. The check-in analyzed is the current trunk (CurrentTrunk, the
// main-branch tip, which the next commit most plausibly descends from);
// when no check-in is on the main branch, it is the newest check-in by
// time, the highest rid breaking a tie. A request that cannot be met -- k
// outside 1..12, no check-in at all to select from, or a file set no k
// partitions -- changes neither setting. It returns the pinned k and the
// warning the operator must be shown: peers that do not announce
// sub-manifest support, every fossil among them, are refused trees, and
// trees cannot be retired.
func (r *Repo) EnableSubmanifests(k int) (pinned int, warning string, err error) {
	current, err := r.CurrentTrunk()
	if errors.Is(err, ErrVersionNotFound) {
		var newest fsltype.FslID
		newest, err = manifest.NewestCheckin(r.inner.DB())
		current = int64(newest)
	}
	if err != nil {
		return 0, "", fmt.Errorf("libfossil: enable sub-manifests: %w", err)
	}
	pinned, err = manifest.EnableSubmanifests(r.inner, fsltype.FslID(current), k)
	if err != nil {
		return 0, "", fmt.Errorf("libfossil: enable sub-manifests: %w", err)
	}
	return pinned, manifest.SubmanifestEnableWarning, nil
}

// RetuneSubmanifests pins a new partition parameter k, 1 to 12, for the
// commits that follow (draft-fossil-submanifests-00 §6.4). It is forward
// only: existing check-ins are unchanged, and the next tree shares only the
// sub-manifests whose bytes are the same under both values.
func (r *Repo) RetuneSubmanifests(k int) error {
	if err := manifest.RetuneSubmanifests(r.inner, k); err != nil {
		return fmt.Errorf("libfossil: re-tune sub-manifests: %w", err)
	}
	return nil
}

// DisableSubmanifests turns tree manifest emission off: later commits are
// flat, and the pinned k is kept for a later EnableSubmanifests. Existing
// trees remain -- artifact names are immutable, so they cannot be retired --
// and keep being served, though peers that do not announce sub-manifest
// support are still refused them. Unlike the CLI's disable, it returns no note saying so; an
// embedder that wants to tell its operator must do it itself.
func (r *Repo) DisableSubmanifests() error {
	if _, err := manifest.DisableSubmanifests(r.inner); err != nil {
		return fmt.Errorf("libfossil: disable sub-manifests: %w", err)
	}
	return nil
}