Commit graph

800 commits

Author SHA1 Message Date
Eelco Dolstra
cb7f25869d
Merge pull request #9430 from hercules-ci/remove-vlas
Fix stack overflow in `filter`
2023-11-30 15:31:44 +01:00
Robert Hensing
4e790efade Use boost::container::small_vector in place of VLAs 2023-11-21 20:52:27 +01:00
Eelco Dolstra
a0162d5732 Improve SourceAccessor path display
Backported from lazy-trees. This allows SourceAccessors to show the
origin of the accessor. E.g. we now get

  copying '«git+https://github.com/blender/blender.git?ref=refs/heads/main&rev=4edc1389337dd3679ff66969c332d2aff52e1992»/' to the store

instead of

  copying '/' to the store
2023-11-20 18:54:36 +01:00
Eelco Dolstra
1d6abec993 Revert use of boost::container::small_vector in the evaluator
It caused random crashes (https://hydra.nixos.org/build/241514506,
https://hydra.nixos.org/build/241443330) because the heap allocation
done by small_vector in the not-small case is not scanned for GC
roots.
2023-11-20 12:35:35 +01:00
Robert Hensing
4a539ac3ea Fix buildNoGc
Fixes https://hydra.nixos.org/build/241067941/nixlog/1

    src/libexpr/eval.cc:1776:54: error: variable 'boost::container::small_vector<nix::Value*, 4> vArgs' has initializer but incomplete type
2023-11-17 17:38:08 +01:00
Robert Hensing
1b9813e4e6 primops: Name stack reservation limits 2023-11-16 15:38:21 +01:00
Robert Hensing
898c47384f primops: Err on the side of less stack usage
Try to stay away from stack overflows.

These small vectors use stack space. Most instances will not need
to allocate because in general most things are small, and large
things are worth heap allocating.

16 * 3 * word = 384 bytes is still quite a bit, but these functions
tend not to be part of deep recursions.
2023-11-16 15:38:21 +01:00
Robert Hensing
91114a6fa4 ExprCall::eval: Heap allocate at arity 5+ 2023-11-16 15:38:21 +01:00
Robert Hensing
0daccb1121 libexpr: Check primop arity earlier 2023-11-16 12:28:32 +01:00
Théophane Hufschmitt
ba3cb4a049 Remove all the occurences of VLAs
There's generally no strict reason for using them, and they are somewhat
fishy, so let's avoid them.
2023-11-16 12:27:30 +01:00
John Ericson
ac89bb064a Split up util.{hh,cc}
All OS and IO operations should be moved out, leaving only some misc
portable pure functions.

This is useful to avoid copious CPP when doing things like Windows and
Emscripten ports.

Newly exposed functions to break cycles:

 - `restoreSignals`
 - `updateWindowSize`
2023-11-05 12:20:02 -05:00
Eelco Dolstra
bcf5c31950 Add future FIXME 2023-10-20 16:58:33 +02:00
Eelco Dolstra
173abec0bc coerceToPath(): Handle __toString, add tests 2023-10-20 13:06:44 +02:00
Eelco Dolstra
5be7705ddf Remove stuff we don't need yet 2023-10-19 19:20:21 +02:00
Eelco Dolstra
f16af08e83 Fix macOS compilation 2023-10-19 14:20:50 +02:00
Eelco Dolstra
12214fef09 InputAccessor::fetchToStore(): Support arbitrary ingestion methods 2023-10-19 14:19:10 +02:00
Eelco Dolstra
df73c6eb8c Introduce MemoryInputAccessor and use it for corepkgs
MemoryInputAccessor is an in-memory virtual filesystem that returns
files like <nix/fetchurl.nix>. This removes the need for special hacks
to handle those files.
2023-10-18 17:38:11 +02:00
Eelco Dolstra
ea38605d11 Introduce FSInputAccessor and use it
Backported from the lazy-trees branch. Note that this doesn't yet use
the access control features of FSInputAccessor.
2023-10-18 17:37:32 +02:00
Jacek Galowicz
54b350d517 Drop some moves that would happen anyway but forbid NRVO where appicable 2023-10-16 21:48:35 +01:00
Jacek Galowicz
abf7df2b37 Fix moves that accidentally copy anyway 2023-10-16 21:48:35 +01:00
Robert Hensing
c32084a12c printStats -> maybePrintStats 2023-10-09 16:34:35 +02:00
Robert Hensing
f95364a803 eval: Run a full GC before printing stats
This makes the numbers more deterministic, especially when it comes
to the final heap size.
2023-10-06 00:21:05 +02:00
Tom Bereknyei
399ef84420 refactor: use string accessors
Create context, string_view, and c_str, accessors throughout in order to
better support improvements to the underlying string representation.
2023-09-27 00:33:01 -04:00
Robert Hensing
3720e811fa libexpr: Add nrExprs to NIX_SHOW_STATS 2023-09-12 13:21:55 +02:00
John Ericson
fe71faa920 Delete EvalState::addToSearchPath
This function is now trivial enough that it doesn't need to exist.

`EvalState` can still be initialized with a custom search path, but we
don't have a need to mutate the search path after it has been
constructed, and I don't see why we would need to in the future.

Fixes #8229
2023-08-18 14:04:33 -04:00
John Ericson
9121fed4b4 Fixing #7479
Types converted:

- `NixStringContextElem`
- `OutputsSpec`
- `ExtendedOutputsSpec`
- `DerivationOutput`
- `DerivationType`

Existing ones mostly conforming the pattern cleaned up:

- `ContentAddressMethod`
- `ContentAddressWithReferences`

The `DerivationGoal::derivationType` field had a bogus initialization,
now caught, so I made it `std::optional`. I think #8829 can make it
non-optional again because it will ensure we always have the derivation
when we construct a `DerivationGoal`.

See that issue (#7479) for details on the general goal.

`git grep 'Raw::Raw'` indicates the two types I didn't yet convert
`DerivedPath` and `BuiltPath` (and their `Single` variants) . This is
because @roberth and I (can't find issue right now...) plan on reworking
them somewhat, so I didn't want to churn them more just yet.

Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
2023-08-18 11:44:00 -04:00
John Ericson
e7c39ff00b Rework evaluator SingleDerivedPath infra
`EvalState::mkSingleDerivedPathString` previously contained its own
inverse (printing, rather than parsing) in order to validate what was
parsed. Now that is pulled out into its own separate function:
`EvalState::coerceToSingleDerivedPath`.

In additional that pulled out logic is deduplicated with
`EvalState::mkOutputString` via `EvalState::mkOutputStringRaw`, which is
itself deduplicated (and generalized) with
`DownstreamPlaceholder::mkOutputStringRaw`.

All these changes make the unit tests simpler.

(We would ideally write more unit tests for `mkSingleDerivedPathString`
`coerceToSingleDerivedPath` directly, but we cannot yet do that because
the IO in reading the store path won't work when the dummy store cannot
hold anything. Someday we'll have a proper in-memory store which will
work for this.)

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
2023-08-14 08:44:50 -04:00
John Ericson
a04720e68c Rename optOutputPath to optStaticOutputPath
This choice of variable name makes it more clear what is going on.

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
2023-08-14 08:44:48 -04:00
John Ericson
60b7121d2c Make the Derived Path family of types inductive for dynamic derivations
We want to be able to write down `foo.drv^bar.drv^baz`:
`foo.drv^bar.drv` is the dynamic derivation (since it is itself a
derivation output, `bar.drv` from `foo.drv`).

To that end, we create `Single{Derivation,BuiltPath}` types, that are
very similar except instead of having multiple outputs (in a set or
map), they have a single one. This is for everything to the left of the
rightmost `^`.

`NixStringContextElem` has an analogous change, and now can reuse
`SingleDerivedPath` at the top level. In fact, if we ever get rid of
`DrvDeep`, `NixStringContextElem` could be replaced with
`SingleDerivedPath` entirely!

Important note: some JSON formats have changed.

We already can *produce* dynamic derivations, but we can't refer to them
directly. Today, we can merely express building or example at the top
imperatively over time by building `foo.drv^bar.drv`, and then with a
second nix invocation doing `<result-from-first>^baz`, but this is not
declarative. The ethos of Nix of being able to write down the full plan
everything you want to do, and then execute than plan with a single
command, and for that we need the new inductive form of these types.

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
2023-08-10 00:08:32 -04:00
Théophane Hufschmitt
5df0f1755f
Merge pull request #8692 from obsidiansystems/add-another-xp-check
Feature gate `DownstreamPlaceholder::unknownCaOutput`
2023-08-07 13:11:44 +02:00
John Ericson
1570e80219 Move evaluator settings (type and global) to separate file/header 2023-07-31 10:14:15 -04:00
John Ericson
caabc4f648 Feature gate DownstreamPlaceholder::unknownCaOutput
This is a part of CA derivations that we forgot to put behind the
experimental feature.

This was caught by @fricklerhandwerk in
https://github.com/NixOS/nix/pull/8369#discussion_r1258133719
2023-07-13 07:56:33 -04:00
John Ericson
be518e73ae Clean up SearchPath
- Better types

- Own header / C++ file pair

- Test factored out methods

- Pass parsed thing around more than strings

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
2023-07-09 23:22:22 -04:00
John Ericson
87dcd09047 Clean up resolveSearchPathElem
We should use `std::optional<std::string>` not `std::pair<bool,
std::string>` for an optional string.
2023-07-09 23:13:30 -04:00
Robert Hensing
7b39a388b3
Merge pull request #8566 from inclyc/nixd/value-print-depth
libexpr: extend `Value::print` to allow limited depth
2023-07-01 20:08:52 +02:00
John Ericson
22b278e011 Automatically document builtin constants
This is done in roughly the same way builtin functions are documented.

Also auto-link experimental features for primops, subsuming PR #8371.

Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
2023-06-27 09:37:54 -04:00
John Ericson
e8067daf09 Generialize showType 2023-06-27 09:11:42 -04:00
Yingchi Long
1400fde144 libexpr: extend Value::print to allow limited depth 2023-06-22 18:28:30 +08:00
Yorick van Pelt
2c462486fe
create pathAccessible, use it to infer default dirs 2023-05-26 15:36:47 +02:00
Yorick van Pelt
a6c78ba367
getDefaultNixPath: ignore EPERM 2023-05-26 15:36:46 +02:00
John Ericson
b9e5ce4a27 Upgrade downstreamPlaceholder to a type with methods
This gets us ready for dynamic derivation dependencies (part of RFC 92).
2023-05-17 17:41:16 -04:00
John Ericson
5a23b80b0a Create EvalState::coerceToDerivedPath
This gives us some round trips to test.

`EvalState::coerceToDerivedPathUnchecked` is a factored out helper just
for unit testing.
2023-05-15 09:03:37 -04:00
John Ericson
8e1a990268 Expose mkOutputString as method of EvalState 2023-05-15 09:03:37 -04:00
Alex Ameen
82296f8113
prevent double quotation 2023-05-09 09:59:18 -05:00
Alex Ameen
b72bc4a972
libexpr: quote reserved keys when printing
This fixes a bug in commands like `nix eval' which would emit invalid attribute
sets if they contained reserved keywords such as "assert", "let", etc.

These keywords will not be quoted when printed, making them valid expressions.
All keywords recognized by the lexer are quoted except "or", which does not
require quotation.
2023-05-09 09:45:12 -05:00
Eelco Dolstra
01232358ff Merge remote-tracking branch 'origin/master' into source-path 2023-04-24 13:20:36 +02:00
John Ericson
85f0cdc370 Use std::set<StringContextElem> not PathSet for string contexts
Motivation

`PathSet` is not correct because string contexts have other forms
(`Built` and `DrvDeep`) that are not rendered as plain store paths.
Instead of wrongly using `PathSet`, or "stringly typed" using
`StringSet`, use `std::std<StringContextElem>`.

-----

In support of this change, `NixStringContext` is now defined as
`std::std<StringContextElem>` not `std:vector<StringContextElem>`. The
old definition was just used by a `getContext` method which was only
used by the eval cache. It can be deleted altogether since the types are
now unified and the preexisting `copyContext` function already suffices.

Summarizing the previous paragraph:

Old:

  - `value/context.hh`: `NixStringContext = std::vector<StringContextElem>`
  - `value.hh`: `NixStringContext Value::getContext(...)`
  - `value.hh`: `copyContext(...)`

New:

  - `value/context.hh`: `NixStringContext = std::set<StringContextElem>`
  - `value.hh`: `copyContext(...)`
----

The string representation of string context elements no longer contains
the store dir. The diff of `src/libexpr/tests/value/context.cc` should
make clear what the new representation is, so we recommend reviewing
that file first. This was done for two reasons:

Less API churn:

`Value::mkString` and friends did not take a `Store` before. But if
`NixStringContextElem::{parse, to_string}` *do* take a store (as they
did before), then we cannot have the `Value` functions use them (in
order to work with the fully-structured `NixStringContext`) without
adding that argument.

That would have been a lot of churn of threading the store, and this
diff is already large enough, so the easier and less invasive thing to
do was simply make the element `parse` and `to_string` functions not
take the `Store` reference, and the easiest way to do that was to simply
drop the store dir.

Space usage:

Dropping the `/nix/store/` (or similar) from the internal representation
will safe space in the heap of the Nix programming being interpreted. If
the heap contains many strings with non-trivial contexts, the saving
could add up to something significant.

----

The eval cache version is bumped.

The eval cache serialization uses `NixStringContextElem::{parse,
to_string}`, and since those functions are changed per the above, that
means the on-disk representation is also changed.

This is simply done by changing the name of the used for the eval cache
from `eval-cache-v4` to eval-cache-v5`.

----

To avoid some duplication `EvalCache::mkPathString` is added to abstract
over the simple case of turning a store path to a string with just that
string in the context.

Context

This PR picks up where #7543 left off. That one introduced the fully
structured `NixStringContextElem` data type, but kept `PathSet context`
as an awkward middle ground between internal `char[][]` interpreter heap
string contexts and `NixStringContext` fully parsed string contexts.

The infelicity of `PathSet context` was specifically called out during
Nix team group review, but it was agreeing that fixing it could be left
as future work. This is that future work.

A possible follow-up step would be to get rid of the `char[][]`
evaluator heap representation, too, but it is not yet clear how to do
that. To use `NixStringContextElem` there we would need to get the STL
containers to GC pointers in the GC build, and I am not sure how to do
that.

----

PR #7543 effectively is writing the inverse of a `mkPathString`,
`mkOutputString`, and one more such function for the `DrvDeep` case. I
would like that PR to have property tests ensuring it is actually the
inverse as expected.

This PR sets things up nicely so that reworking that PR to be in that
more elegant and better tested way is possible.

Co-authored-by: Théophane Hufschmitt <7226587+thufschmitt@users.noreply.github.com>
2023-04-21 01:05:49 -04:00
Robert Hensing
cb2615cf47 Merge remote-tracking branch 'upstream/master' into source-path 2023-04-17 11:41:50 +02:00
Robert Hensing
28a5cdde02 libexpr/value/print.* -> libexpr/print.*
Generalizes the file to sensibly allow printing any part of the
language syntax.
2023-04-16 13:10:45 +02:00
Robert Hensing
1e2dd669bc printLiteral: Do not overload 2023-04-16 13:04:35 +02:00