Add 'infra/libkookie/' from commit 'd661aa56a8843e991261510c1bb28fdc2f6975ae'

git-subtree-dir: infra/libkookie
git-subtree-mainline: 49f735974dd103039ddc4cb576bb76555164a9e7
git-subtree-split: d661aa56a8843e991261510c1bb28fdc2f6975ae

1 files changed, 71 insertions, 0 deletions

diff --git a/infra/libkookie/nixpkgs/pkgs/build-support/setup-hooks/role.bash b/infra/libkookie/nixpkgs/pkgs/build-support/setup-hooks/role.bash
new file mode 100644
index 000000000000..cf69e732e7c3
--- /dev/null
+++ b/infra/libkookie/nixpkgs/pkgs/build-support/setup-hooks/role.bash
@@ -0,0 +1,71 @@
+# Since the same derivation can be depend 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 intened to be use 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 inteneded specifically for code-prodocing 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
+}