Commit graph

13 commits

Author SHA1 Message Date
Vincent Ambo
26b55f8cda fix(tvix/cli): use tvlfyi/wu-manber fork for refscanner
Our fork fixes a small bug (https://github.com/jneem/wu-manber/pull/1)
but it's not clear whether upstream will accept patches, so for now
lets point this directly at our fork.

Change-Id: Iccdcedae3e9a8b783241431787c952561d032694
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8031
Reviewed-by: tazjin <tazjin@tvl.su>
Autosubmit: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
2023-02-04 12:44:59 +00:00
Vincent Ambo
9d6f29a72b refactor(tvix/cli): use Wu-Manber string scanning for drv references
Switch out the string-scanning algorithm used in the reference scanner.

The construction of aho-corasick automata made up the vast majority of
runtime when evaluating nixpkgs previously. While the actual scanning
with a constructed automaton is relatively fast, we almost never scan
for the same set of strings twice and the cost is not worth it.

An algorithm that better matches our needs is the Wu-Manber multiple
string match algorithm, which works efficiently on *long* and *random*
strings of the *same length*, which describes store paths (up to their
hash component).

This switches the refscanner crate to a Rust implementation[0][1] of
this algorithm.

This has several implications:

1. This crate does not provide a way to scan streams. I'm not sure if
   this is an inherent problem with the algorithm (probably not, but
   it would need buffering). Either way, related functions and
   tests (which were actually unused) have been removed.

2. All strings need to be of the same length. For this reason, we
   truncate the known paths after their hash part (they are still
   unique, of course).

3. Passing an empty set of matches, or a match that is shorter than
   the length of a store path, causes the crate to panic. We safeguard
   against this by completely skipping the refscanning if there are no
   known paths (i.e. when evaluating the first derivation of an eval),
   and by bailing out of scanning a string that is shorter than a
   store path.

On the upside, this reduces overall runtime to less 1/5 of what it was
before when evaluating `pkgs.stdenv.drvPath`.

[0]: Frankly, it's a random, research-grade MIT-licensed
     crate that I found on Github:

     https://github.com/jneem/wu-manber

[1]: We probably want to rewrite or at least fork the above crate, and
     add things like a three-byte wide scanner. Evaluating large
     portions of nixpkgs can easily lead to more than 65k derivations
     being scanned for.

Change-Id: I08926778e1e5d5a87fc9ac26e0437aed8bbd9eb0
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8017
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
2023-02-02 17:50:44 +00:00
Florian Klink
2d24c5f260 refactor(tvix/nix-compat): absorb //tvix/derivation
Put this in its src/derivation.

Change-Id: Ic047ab1c2da555a833ee454e10ef60c77537b617
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7967
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Autosubmit: flokli <flokli@flokli.de>
2023-01-31 15:16:39 +00:00
Florian Klink
c27bacd905 refactor(tvix): introduce nix-compat crate
Move nixbase32 and store_path into this.

This allows //tvix/cli to not pull in //tvix/store for now.

Change-Id: Id3a32867205d95794bc0d33b21d4cb3d9bafd02a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7964
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
2023-01-31 13:26:18 +00:00
Florian Klink
4b3ccd205a refactor(tvix/cli): absorb construct_output_hash
This helper function only was created because
populate_output_configuration was hard to test before cl/7939.

With that out of the way, we can pull it in.

Change-Id: I64b36c0eb34343290a8d84a03b0d29392a821fc7
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7961
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
2023-01-31 08:52:00 +00:00
Florian Klink
e3c2b3650a refactor(tvix/cli): describe errors with thiserror
This is much less code, and makes it much easier to read.

Change-Id: I9028f226105f905c2cc2cabd33907ff493e26225
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7938
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Autosubmit: flokli <flokli@flokli.de>
2023-01-27 14:08:15 +00:00
Florian Klink
a94a1434cc fix(tvix/cli): handle SRI hashes in outputHash
Instead of being called with `md5`, `sha1`, `sha256` or `sha512`,
`fetchurl.nix` (from corepkgs / `<nix`) can also be called with a `hash`
attribute, being an SRI hash.

In that case, `builtin.derivation` is called with `outputHashAlgo` being
an empty string, and `outputHash` being an SRI hash string.

In other cases, an SRI hash is passed as outputHash, but outputHashAlgo
is set too.

Nix does modify these values in (single, fixed) output specification it
serializes to ATerm, but keeps it unharmed in `env`.

Move this into a construct_output_hash helper function, that can be
tested better in isolation.

Change-Id: Id9d716a119664c44ea7747540399966752e20187
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7933
Reviewed-by: tazjin <tazjin@tvl.su>
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
2023-01-27 14:06:13 +00:00
Vincent Ambo
259faea2b2 feat(tvix/cli): add errors module with drv construction errors
These will be threaded through to eval through the new `TvixError`
variant.

Change-Id: Ia0d3f8710dcf26bb95015cd2a6a2b2911f06343f
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7842
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
2023-01-20 15:39:51 +00:00
Vincent Ambo
3045645df0 feat(tvix/cli): implement initial refscan module
This module implements a ReferenceScanner struct which uses the
aho_corasick crate to scan string inputs for known, non-overlapping
candidates (store paths, in our case).

I experimented with several different APIs, and landed on this version
with an initial accumulator in the scanner. The scanner is
instantiated from the candidates and "fed" all the strings, then
consumed by the caller to retrieve the result.

Right now only things that look vaguely like bytestrings can be fed to
the scanner, there is no streaming support in the API yet.

Change-Id: I7782f0f0df5fc64bccd813aa14712f5525b0168c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7808
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
2023-01-11 16:03:51 +00:00
Vincent Ambo
ea7d63e177 feat(tvix/cli): implement NixCompatIO helper type
This type allows for temporarily compatibility with the C++ Nix store,
specifically (for now) it gives us the store directory used by Nix and
imports files the same way.

Change-Id: I4767794ef2863eba49661315c63c4e17de946d60
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7587
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
2022-12-22 19:09:40 +00:00
Vincent Ambo
8b3d03db92 chore(tvix/cli): rename binary to just 'tvix'
Change-Id: If735c81a04f60dcd77f1c40b595b52ed88bbbe95
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7580
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Reviewed-by: flokli <flokli@flokli.de>
2022-12-21 21:48:08 +00:00
Vincent Ambo
257c67f204 chore(tvix): upgrade to clap 4.0
In //tvix/eval:

* criterion bumped to 4.0, which at least depends on clap 3.x instead
  of 2.x, which is less incompatible

In //tvix/cli:

* no changes required

In //tvix/nix_cli:

* some minor changes for compatibility with clap 4.0, no functionality
  changes

Change-Id: If793f64b59fcaa2402d3d483ddbab4092f32df03
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7588
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
2022-12-21 13:23:38 +00:00
Vincent Ambo
d9e2bec953 refactor(tvix): split binary (REPL etc.) out from evaluator library
The tvix-eval project is independent from any *uses* of the evaluator,
such as the tvix-repl.

This functionality has been split out into a separate "tvix-cli"
crate. Note that this doesn't have to mean that this CLI crate is the
"final" CLI crate for tvix, the point of this is not "getting the CLI
structure right" but rather "getting the evaluator structure right".

This reshuffling is part of restructuring the way that functionality
like store communication is injected into language evaluation.

Note that at this commit the new CLI crate is not at feature-parity.

Change-Id: Id0af03dc8e07ef09a9f882a89612ad555eca8f93
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7541
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
2022-12-21 13:09:29 +00:00