nixpkgs/pkgs/build-support/setup-hooks/role.bash
2023-05-31 04:00:14 +04:00

72 lines
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# Since the same derivation can be depended on in multiple ways, we need to
# accumulate *each* role (i.e. host and target platforms relative the depending
# derivation) in which the derivation is used.
#
# The role is intended to be used as part of other variables names like
# - $NIX_SOMETHING${role_post}
function getRole() {
case $1 in
-1)
role_post='_FOR_BUILD'
;;
0)
role_post=''
;;
1)
role_post='_FOR_TARGET'
;;
*)
echo "@name@: used as improper sort of dependency" >&2
return 1
;;
esac
}
# `hostOffset` describes how the host platform of the package is slid relative
# to the depending package. `targetOffset` likewise describes the target
# platform of the package. Both are brought into scope of the setup hook defined
# for dependency whose setup hook is being processed relative to the package
# being built.
function getHostRole() {
getRole "$hostOffset"
}
function getTargetRole() {
getRole "$targetOffset"
}
# `depHostOffset` describes how the host platform of the dependencies are slid
# relative to the depending package. `depTargetOffset` likewise describes the
# target platform of dependenices. Both are brought into scope of the
# environment hook defined for the dependency being applied relative to the
# package being built.
function getHostRoleEnvHook() {
getRole "$depHostOffset"
}
function getTargetRoleEnvHook() {
getRole "$depTargetOffset"
}
# This variant is intended specifically for code-producing tool wrapper scripts
# `NIX_@wrapperName@_TARGET_*_@suffixSalt@` tracks this (needs to be an exported
# env var so can't use fancier data structures).
function getTargetRoleWrapper() {
case $targetOffset in
-1)
export NIX_@wrapperName@_TARGET_BUILD_@suffixSalt@=1
;;
0)
export NIX_@wrapperName@_TARGET_HOST_@suffixSalt@=1
;;
1)
export NIX_@wrapperName@_TARGET_TARGET_@suffixSalt@=1
;;
*)
echo "@name@: used as improper sort of dependency" >&2
return 1
;;
esac
}