repo: Support reading and upgrading from older composefs-rs repos#285
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cgwalters merged 1 commit intocomposefs:mainfrom Apr 27, 2026
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repo: Support reading and upgrading from older composefs-rs repos#285cgwalters merged 1 commit intocomposefs:mainfrom
cgwalters merged 1 commit intocomposefs:mainfrom
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Production bootc (pinned at composefs-rs 2203e8f) predates three format changes: - ce66285 repository: Add meta.json for repo metadata and cfsctl init - b7dc270 Add repr(c) for SplitStream header structs - d5ec81d oci: Generate composefs EROFS at pull time, track via config refs This commit adds transparent backward compatibility and a non-destructive upgrade path. The splitstream reader detects old-layout headers (where the Rust compiler reordered SplitstreamHeader fields) and converts them on the fly. Repository::open_upgrade() infers the algorithm and verity mode from existing objects when meta.json is missing, writes it, and opens normally — replacing the destructive --reset-metadata flow. upgrade_repo() walks all tagged images and generates EROFS for any that lack it, rewriting config and manifest splitstreams in the current format. Layer splitstreams stay old-format on disk since the reader handles them transparently. The CLI uses open_upgrade by default (opt out with --no-upgrade). An integration test pulls a real image with an old cfsctl binary (requires CFSCTL_PATH_OLD) to verify the full upgrade path. Assisted-by: OpenCode (Claude Opus 4) Signed-off-by: Colin Walters <walters@verbum.org>
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Update composefs-rs to rev b95b1a0b2f which adds support for reading splitstreams written by bootc <= 1.15.x. Those builds were missing #[repr(C)] on SplitstreamHeader, causing the Rust compiler to reorder fields for alignment. The new composefs-rs detects this old layout and translates the header transparently. Switch the initramfs from init_path() to open_upgrade(), which handles the meta.json migration non-destructively: it infers the algorithm and verity mode from existing objects instead of requiring them as arguments. See: composefs/composefs-rs#285 Assisted-by: OpenCode (Claude Opus 4)
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Add unified storage support to the composefs path, leveraging the new support for containers-storage. See: composefs/composefs-rs#285 Assisted-by: OpenCode (Claude Opus 4) Assisted-by: OpenCode (Claude Sonnet 4.6) Signed-off-by: Colin Walters <walters@verbum.org>
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Add unified storage support to the composefs path, leveraging the new support for containers-storage. See: composefs/composefs-rs#285 Assisted-by: OpenCode (Claude Opus 4) Assisted-by: OpenCode (Claude Sonnet 4.6) Signed-off-by: Colin Walters <walters@verbum.org>
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Add unified storage support to the composefs path, leveraging the new support for containers-storage. See: composefs/composefs-rs#285 Assisted-by: OpenCode (Claude Opus 4) Assisted-by: OpenCode (Claude Sonnet 4.6) Signed-off-by: Colin Walters <walters@verbum.org>
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Production bootc (pinned at composefs-rs 2203e8f) predates three format changes:
This commit adds transparent backward compatibility and a non-destructive upgrade path.
The splitstream reader detects old-layout headers (where the Rust compiler reordered SplitstreamHeader fields) and converts them on the fly. Repository::open_upgrade() infers the algorithm and verity mode from existing objects when meta.json is missing, writes it, and opens normally — replacing the destructive --reset-metadata flow. upgrade_repo() walks all tagged images and generates EROFS for any that lack it, rewriting config and manifest splitstreams in the current format. Layer splitstreams stay old-format on disk since the reader handles them transparently.
The CLI uses open_upgrade by default (opt out with --no-upgrade). An integration test pulls a real image with an old cfsctl binary (requires CFSCTL_PATH_OLD) to verify the full upgrade path.
Assisted-by: OpenCode (Claude Opus 4)