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fix(core): detect NFS and use local database path to prevent corruption#15131

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jerry-xu0514 wants to merge 2 commits intoanomalyco:devfrom
jerry-xu0514:fix/sqlite-nfs-corruption
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fix(core): detect NFS and use local database path to prevent corruption#15131
jerry-xu0514 wants to merge 2 commits intoanomalyco:devfrom
jerry-xu0514:fix/sqlite-nfs-corruption

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@jerry-xu0514 jerry-xu0514 commented Feb 25, 2026

Issue for this PR

Closes #14970

Type of change

  • Bug fix
  • New feature
  • Refactor / code improvement
  • Documentation

What does this PR do?

SQLite's WAL mode uses shared memory mappings (mmap) via the -shm file. On NFS, these mappings are incoherent across clients and POSIX fcntl() locks are unreliable. Multiple opencode sessions writing to the same WAL-mode database on NFS corrupts the database almost immediately.

This PR:

  1. Detects NFS via statfsSync().type === 0x6969 and redirects the database to /tmp/opencode-{uid}/ on a local filesystem
  2. Adds an integrity check on startup — if corruption is detected, the database is auto-recreated instead of crashing
  3. Wraps wal_checkpoint in try/catch to handle stale WAL state

How did you verify your code works?

Tested on a live NFSv3 environment (local_lock=none) where the bug reproduces consistently:

  • Confirmed statfsSync returns 0x6969 for the NFS mount
  • Built and installed the patched binary; new sessions create the database at /tmp/opencode-{uid}/opencode.db instead of the NFS path
  • Deliberately corrupted a test database; the integrity check detected it and auto-recreated on startup instead of crashing

Screenshots / recordings

N/A — no UI changes.

Checklist

  • I have tested my changes locally
  • I have not included unrelated changes in this PR

SQLite's WAL mode uses shared memory mappings (mmap) via the -shm file,
which are incoherent across NFS clients. This causes database corruption
when multiple opencode sessions write concurrently on NFS-mounted home
directories.

Detect NFS via statfs magic number (0x6969) and fall back to a local
tmpdir path. Also add integrity checks on startup with auto-recreation
to make corruption self-healing instead of a hard crash.

Fixes anomalyco#14970
@github-actions github-actions bot added needs:compliance This means the issue will auto-close after 2 hours. and removed needs:compliance This means the issue will auto-close after 2 hours. labels Feb 25, 2026
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Thanks for updating your PR! It now meets our contributing guidelines. 👍

The previous approach tried to move the database to /tmp on NFS, but:
- Was never deployed (installed binary was still the old one)
- Would lose data on reboot
- Used integrity_check which hangs on large corrupt databases

New approach:
- Detect NFS via statfsSync and use DELETE journal mode (no mmap/-shm)
- Use quick_check instead of integrity_check (fast, won't hang)
- Set busy_timeout before journal mode change (NFS stale locks)
- Wrap journal mode change in try/catch (graceful fallback)
- Keep corruption recovery as defense in depth
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SQLite database corruption (database disk image is malformed) when running concurrent sessions on NFS

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