This is accomplished by comparing the hashes that the unit files
contain. By filtering for a special key `X-Reload-Triggers` in the
`[Unit]` section, we can differentiate between reloads and restarts.
Since activation scripts can request reloads of units as well, more
checking of this behaviour is implemented. If a unit is to be restarted,
it's never reloaded as well which would make no sense.
Also removes a useless subroutine and perl dependencies that are
nowadays handled by the propagated build inputs feature of
`perl.withPackages`.
The `nix.*` options, apart from options for setting up the
daemon itself, currently provide a lot of setting mappings
for the Nix daemon configuration. The scope of the mapping yields
convience, but the line where an option is considered essential
is blurry. For instance, the `extra-sandbox-paths` mapping is
provided without its primary consumer, and the corresponding
`sandbox-paths` option is also not mapped.
The current system increases the maintenance burden as maintainers have to
closely follow upstream changes. In this case, there are two state versions
of Nix which have to be maintained collectively, with different options
avaliable.
This commit aims to following the standard outlined in RFC 42[1] to
implement a structural setting pattern. The Nix configuration is encoded
at its core as key-value pairs which maps nicely to attribute sets, making
it feasible to express in the Nix language itself. Some existing options are
kept such as `buildMachines` and `registry` which present a simplified interface
to managing the respective settings. The interface is exposed as `nix.settings`.
Legacy configurations are mapped to their corresponding options under `nix.settings`
for backwards compatibility.
Various options settings in other nixos modules and relevant tests have been
updated to use structural setting for consistency.
The generation and validation of the configration file has been modified to
use `writeTextFile` instead of `runCommand` for clarity. Note that validation
is now mandatory as strict checking of options has been pushed down to the
derivation level due to freeformType consuming unmatched options. Furthermore,
validation can not occur when cross-compiling due to current limitations.
A new option `publicHostKey` was added to the `buildMachines`
submodule corresponding to the base64 encoded public host key settings
exposed in the builder syntax. The build machine generation was subsequently
rewritten to use `concatStringsSep` for better performance by grouping
concatenations.
[1] - https://github.com/NixOS/rfcs/blob/master/rfcs/0042-config-option.md
Modules that do not depend on e.g. toplevel should not have to include it just to set
things in `system.build`. As a general rule, this keeps tests simple, usage flexible
and evaluation fast. While one module is insignificant, consistency and good practices
are.
This replaces the naive K=V unit parser with a proper INI parser from a
library and adds proper support for override files. Also adds a bunch of
comments about parsing, I hope this makes it easier to understand and
maintain in the future.
There are multiple reasons to do so, the first one is just general
correctness with is nice imo. But to get to more serious reasons (I
didn't put in all that effort for nothing) is that this is the first
step torwards more clever restart/reload handling. By using a library
like Data::Compare a future PR could replace the current way of
fingerprinting units (which is to compare store paths) by comparing the
hashes. This is more precise because units won't get restarted because
the order of the options change, comments are added, some dependency of
writeText changes, .... Also this allows us to add a feature like
`X-Reload-Triggers` so the unit can either be reloaded when these change
or restarted when everything else changes, giving module authors the
ability to have their services reloaded without having to fear that
updates are not applied because the service doesn't get restarted.
Another reason why this feature is nice is that now that the unit files
are parsed correctly (and values are just extracted from one section),
potential future rewrites can just rely on some INI library without
having to implement their own weird parser that is compatible with this
script.
This also comes with a new subroutine to handle systemd booleans because
I thought the current way of handling it was just ugly. This also allows
overriding values this script reads in an override file.
Apart from making this script more compatible with the world around it,
this also fixes two issues I saw bugging exactly 0 (zero) people. First
is that this script now supports multiple override files, also ones that
are not called override.conf and the second one is that `1` and `on` are
treated as bools by systemd but were previously not parsed as such by
switch-to-configuration.
most modules can be evaluated for their documentation in a very
restricted environment that doesn't include all of nixpkgs. this
evaluation can then be cached and reused for subsequent builds, merging
only documentation that has changed into the cached set. since nixos
ships with a large number of modules of which only a few are used in any
given config this can save evaluation a huge percentage of nixos
options available in any given config.
in tests of this caching, despite having to copy most of nixos/, saves
about 80% of the time needed to build the system manual, or about two
second on the machine used for testing. build time for a full system
config shrank from 9.4s to 7.4s, while turning documentation off
entirely shortened the build to 7.1s.
Add `shellDryRun` to the generic stdenv and substitute it for uses of
`${stdenv.shell} -n`. The point of this layer of abstraction is to add
the flag `-O extglob`, which resolves#126344 in a more direct way.
This reverts commit 57961d2b83, reversing
changes made to b04f913afc.
(I.e. this reverts PR #141192.)
While well-intended, this change does unfortunately introduce very
serious regressions that are especially disruptive/noticeable on desktop
systems (e.g. users of Sway will loose their graphical session when
running "nixos-rebuild switch").
Therefore, this change has to be reverted ASAP instead of trying to fix
it in "production".
Note: An updated version should be extensively discussed, reviewed, and
tested before re-landing this change as an earlier version also had to
be reverted for the exact same issues [0].
Fix: #146727
[0]: https://github.com/NixOS/nixpkgs/pull/73871#issuecomment-559783752
By using the new extendModules function to produce the specialisations,
we avoid reimplementing the eval-config.nix logic in reverse and fix
cross compilation support for specialisations in the process.
When cross-compiling, we can't run the runtime shell to check syntax
if it's e.g. for a different architecture. We have two options here.
We can disable syntax checking when cross compiling, but that risks
letting errors through. Or, we can do what I've done here, and change
the syntax check to use stdenv's shell instead of the runtime shell.
This requires the stdenv shell and runtime shell to be broadly
compatible, but I think that's so ingrained in Nixpkgs anyway that
it's fine. And this way we avoid conditionals that check for cross.
Since 03eaa48 added perl.withPackages, there is a canonical way to
create a perl interpreter from a list of libraries, for use in script
shebangs or generic build inputs. This method is declarative (what we
are doing is clear), produces short shebangs[1] and needs not to wrap
existing scripts.
Unfortunately there are a few exceptions that I've found:
1. Scripts that are calling perl with the -T switch. This makes perl
ignore PERL5LIB, which is what perl.withPackages is using to inform
the interpreter of the library paths.
2. Perl packages that depends on libraries in their own path. This
is not possible because perl.withPackages works at build time. The
workaround is to add `-I $out/${perl.libPrefix}` to the shebang.
In all other cases I propose to switch to perl.withPackages.
[1]: https://lwn.net/Articles/779997/
The `platform` field is pointless nesting: it's just stuff that happens
to be defined together, and that should be an implementation detail.
This instead makes `linux-kernel` and `gcc` top level fields in platform
configs. They join `rustc` there [all are optional], which was put there
and not in `platform` in anticipation of a change like this.
`linux-kernel.arch` in particular also becomes `linuxArch`, to match the
other `*Arch`es.
The next step after is this to combine the *specific* machines from
`lib.systems.platforms` with `lib.systems.examples`, keeping just the
"multiplatform" ones for defaulting.
The toplevel derivations of systems that have `networking.hostName`
set to `""` (because they want their hostname to be set by DHCP) used
to be all named
`nixos-system-unnamed-${config.system.nixos.label}`.
This makes them hard to distinguish.
A similar problem existed in NixOS tests where `vmName` is used in the
`testScript` to refer to the VM. It defaulted to the
`networking.hostName` which when set to `""` won't allow you to refer
to the machine from the `testScript`.
This commit makes the `system.name` configurable. It still defaults to:
```
if config.networking.hostName == ""
then "unnamed"
else config.networking.hostName;
```
but in case `networking.hostName` needs to be to `""` the
`system.name` can be set to a distinguishable name.
`$toplevel/system` of a system closure with `x86_64` kernel and `i686` userland should contain "x86_64-linux".
If `$toplevel/system` contains "i686-linux", the closure will be run using `qemu-system-i386`, which is able to run `x86_64` kernel on most Intel CPU, but fails on AMD.
So this fix is for a rare case of `x86_64` kernel + `i686` userland + AMD CPU
This avoids a possible surprise if the user is using `nixpkgs.system`
and `nesting.children`. `nesting.children` is expected to ignore all
parent configuration so we shouldn't propagate the user-facing option
`nixpkgs.system`. To avoid doing so, we introduce a new internal
option for holding the value passed to eval-config.nix, and use that
when recursing for nesting.
