nixpkgs/pkgs/build-support/buildenv/default.nix
tilpner 77f1c7d5bc
buildenv: Make buildEnv overridable
callPackage already calls makeOverridable, but that just
makes the function that evaluates to buildEnv overridable,
not buildEnv itself.
If no overridable version of buildEnv is used during construction,
users can't override e.g. `paths` at all
2017-08-02 11:56:37 +02:00

73 lines
2.4 KiB
Nix

# buildEnv creates a tree of symlinks to the specified paths. This is
# a fork of the buildEnv in the Nix distribution. Most changes should
# eventually be merged back into the Nix distribution.
{ buildPackages, runCommand, lib }:
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${extraPrefix}", e.g. "/share".
extraPrefix ? ""
, # Shell commands to run after building the symlink tree.
postBuild ? ""
, # Additional inputs. Handy e.g. if using makeWrapper in `postBuild`.
buildInputs ? []
, passthru ? {}
, meta ? {}
}:
runCommand name
rec {
inherit manifest ignoreCollisions checkCollisionContents passthru
meta pathsToLink extraPrefix postBuild buildInputs;
pkgs = builtins.toJSON (map (drv: {
paths =
# First add the usual output(s): respect if user has chosen explicitly,
# and otherwise use `meta.outputsToInstall`. The attribute is guaranteed
# to exist in mkDerivation-created cases. The other cases (e.g. runCommand)
# aren't expected to have multiple outputs.
(if drv.outputUnspecified or false
&& drv.meta.outputsToInstall or null != null
then map (outName: drv.${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;
# XXX: The size is somewhat arbitrary
passAsFile = if builtins.stringLength pkgs >= 128*1024 then [ "pkgs" ] else null;
}
''
${buildPackages.perl}/bin/perl -w ${./builder.pl}
eval "$postBuild"
'')