nixpkgs/pkgs/build-support/buildenv/default.nix
Robert Hensing fcea105698 buildEnv: Nix's buildEnv should be stable
It's mostly used by nix-env, but Nix should remain simple and small
for reproducibility.
2023-07-06 16:13:38 +02:00

82 lines
2.5 KiB
Nix

# buildEnv creates a tree of symlinks to the specified paths. This is
# a fork of the hardcoded buildEnv in the Nix distribution.
{ buildPackages, runCommand, lib, substituteAll }:
lib.makeOverridable
({ name
, # The manifest file (if any). A symlink $out/manifest will be
# created to it.
manifest ? ""
, # The paths to symlink.
paths
, # Whether to ignore collisions or abort.
ignoreCollisions ? false
, # If there is a collision, check whether the contents and permissions match
# and only if not, throw a collision error.
checkCollisionContents ? true
, # The paths (relative to each element of `paths') that we want to
# symlink (e.g., ["/bin"]). Any file not inside any of the
# directories in the list is not symlinked.
pathsToLink ? ["/"]
, # The package outputs to include. By default, only the default
# output is included.
extraOutputsToInstall ? []
, # Root the result in directory "$out${extraPrefix}", e.g. "/share".
extraPrefix ? ""
, # Shell commands to run after building the symlink tree.
postBuild ? ""
# Additional inputs
, nativeBuildInputs ? [] # Handy e.g. if using makeWrapper in `postBuild`.
, buildInputs ? []
, passthru ? {}
, meta ? {}
}:
let
builder = substituteAll {
src = ./builder.pl;
inherit (builtins) storeDir;
};
in
runCommand name
rec {
inherit manifest ignoreCollisions checkCollisionContents passthru
meta pathsToLink extraPrefix postBuild
nativeBuildInputs buildInputs;
pkgs = builtins.toJSON (map (drv: {
paths =
# First add the usual output(s): respect if user has chosen explicitly,
# and otherwise use `meta.outputsToInstall`. The attribute is guaranteed
# to exist in mkDerivation-created cases. The other cases (e.g. runCommand)
# aren't expected to have multiple outputs.
(if (! drv ? outputSpecified || ! drv.outputSpecified)
&& drv.meta.outputsToInstall or null != null
then map (outName: drv.${outName}) drv.meta.outputsToInstall
else [ drv ])
# Add any extra outputs specified by the caller of `buildEnv`.
++ lib.filter (p: p!=null)
(builtins.map (outName: drv.${outName} or null) extraOutputsToInstall);
priority = drv.meta.priority or 5;
}) paths);
preferLocalBuild = true;
allowSubstitutes = false;
# XXX: The size is somewhat arbitrary
passAsFile = if builtins.stringLength pkgs >= 128*1024 then [ "pkgs" ] else [ ];
}
''
${buildPackages.perl}/bin/perl -w ${builder}
eval "$postBuild"
'')