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This release fixes some bugs in dqlite's build system that were introduced when developing the --enable-build-raft option:

• Fix building without --enable-build-raft when liblz4 is not available: https://github.com/canonical/dqlite/pull/603
• Fix building with vendored sqlite3.c: https://github.com/canonical/dqlite/pull/607

It also introduces code for a new thread pool that will be used in future versions of dqlite, but is not currently enabled:

• https://github.com/canonical/dqlite/pull/598

This release brings a new option for dqlite's configure script, --enable-build-raft. When this option is passed, dqlite will build and use a private Raft implementation instead of linking to an external libraft. --enable-build-raft is the preferred way to use dqlite going forward, but linking to an external libraft remains supported for now, and is the default if the new flag is not passed.

One other internal change is included in this release:

• Fix many cases of arithmetic on void pointers (https://github.com/canonical/dqlite/pull/569)

This release brings a fix for using dqlite with SQLite versions greater than 3.45.0 (#564), plus:

• A more readable logging format (#542).
• An internal improvement to how dqlite reacts to Raft state changes (#545).
• A new dqlite_node configuration option to control snapshot compression (#567, thanks to new contributor @cnnrznn).

This release exposes one new API, dqlite_node_set_auto_recovery. See #526.

This release is functionally the same as v1.15.0, but is part of the master branch history. Some new APIs (dqlite_server_create, etc.) are declared in dqlite.h, marked with DQLITE_EXPERIMENTAL.

This release includes:

• Various bug fixes to help dqlite correctly handle large databases (#459, #460)
• Fixes and cleanup for the internal dqlite client API (#458)
• Fixes and cleanup for dqlite's handling of client connections (#476)
• Support for SQL queries that both modify the database and return rows, using the QUERY and QUERY_SQL requests (#477)
• Support for server-side cluster role management (#480)

As well as other miscellaneous bug fixes and improvements.

This release bumps the required version of libraft to 0.17.1 and adapts some internal dqlite code for changes in the raft.h API.

• Provide a disk-mode for dqlite. See #401 for details. WARNING: This API is considered EXPERIMENTAL and UNSTABLE and NOT SUITABLE for production use! It is possible the behavior of the disk-mode will change in the future and it cannot be guaranteed that systems running disk-mode like it exists in this release will be compatible with future versions.
• Fix an issue that limited the maximum row size #445

• Support more statement parameters than 255, see https://github.com/canonical/dqlite/pull/407
• requires libraft 0.16.0
• Bugfixes

• Replace deprecated raft function raft_fixture_init with raft_fixture_initialize