feat: unprivileged read-only open of SQLite DB

If the state SQLite database is configured to use a write-ahead-log, it
creates WAL files in the state directory.

When the state SQLite database is closed by the `nix-daemon` after
builds, those files are removed.

When an unprivileged user would like to open _in read only_ that
database, they cannot do so because they would need to create those WAL
files and they do not have the permission to do so.

For this, SQLite offers a "persistent WAL" feature [1] to leave the WAL
files around, even after closing the database.

This CL enable the persistent WAL mode.

Fixes: https://github.com/NixOS/nix/issues/10300
[1]: https://www.sqlite.org/wal.html

Change-Id: Id8ae534d7d2290457af28782e5215222ae051fe5
Signed-off-by: Raito Bezarius <raito@lix.systems>

0 files changed, 0 insertions, 0 deletions