# tor-dirmgr
Code to fetch, store, and update Tor directory information.
## Overview
This crate is part of
[Arti](https://gitlab.torproject.org/tpo/core/arti/), a project to
implement [Tor](https://www.torproject.org/) in Rust.
In its current design, Tor requires a set of up-to-date
authenticated directory documents in order to build multi-hop
anonymized circuits through the network.
This directory manager crate is responsible for figuring out which
directory information we lack, downloading what we're missing, and
keeping a cache of it on disk.
## Compile-time features
* `mmap` (default) -- Use memory mapping to reduce the memory load for
reading large directory objects from disk.
* `routerdesc` -- (Incomplete) support for downloading and storing
router descriptors.
* `compression` (default) -- Build support for downloading compressed
documents. Requires a C compiler.
* `bridge-client`: Provide APIs used to fetch
and use bridge information.
* `full` -- Enable all features above.
### Non-additive features
* `static` -- Try to link with a static copy of sqlite3.
### Experimental and unstable features
Note that the APIs enabled by these features are NOT covered by
semantic versioning[^1] guarantees: we might break them or remove
them between patch versions.
* `experimental-api`: Add additional non-stable APIs to our public
interfaces.
* `dirfilter`: enable an experimental mechanism to modify incoming
directory information before it is used.
* `experimental`: Enable all the above experimental features.
features work reliably. To be explicit: if you want `cargo update`
to _only_ make safe changes, then you cannot enable these
features.
License: MIT OR Apache-2.0