treewide: Use pkgs/build-support/roles.bash to remove copy pasta

Also fix some setup hooks that unnecessarily used environment hooks,
which revolted in the same variable being modified too many times.

5 files changed, 103 insertions, 73 deletions

diff --git a/pkgs/build-support/bintools-wrapper/default.nix b/pkgs/build-support/bintools-wrapper/default.nix
index 47301bbdde6..c0aea2d1131 100644
--- a/pkgs/build-support/bintools-wrapper/default.nix
+++ b/pkgs/build-support/bintools-wrapper/default.nix
@@ -190,7 +190,12 @@ stdenv.mkDerivation {
 
   depsTargetTargetPropagated = extraPackages;
 
-  setupHook = ./setup-hook.sh;
+  wrapperName = "BINTOOLS_WRAPPER";
+
+  setupHooks = [
+    ../setup-hooks/role.bash
+    ./setup-hook.sh
+  ];
 
   postFixup =
     ''
diff --git a/pkgs/build-support/bintools-wrapper/setup-hook.sh b/pkgs/build-support/bintools-wrapper/setup-hook.sh
index 48a00b0b9b0..dbe0a0572a4 100644
--- a/pkgs/build-support/bintools-wrapper/setup-hook.sh
+++ b/pkgs/build-support/bintools-wrapper/setup-hook.sh
@@ -11,44 +11,22 @@ set -u
 [[ -z ${crossConfig-} ]] || (( "$hostOffset" < 0 )) || return 0
 
 bintoolsWrapper_addLDVars () {
-    case $depHostOffset in
-        -1) local role='BUILD_' ;;
-        0)  local role='' ;;
-        1)  local role='TARGET_' ;;
-        *)  echo "bintools-wrapper: Error: Cannot be used with $depHostOffset-offset deps" >2;
-            return 1 ;;
-    esac
+    # See ../setup-hooks/role.bash
+    local role_post role_pre
+    getTargetRoleEnvHook
 
     if [[ -d "$1/lib64" && ! -L "$1/lib64" ]]; then
-        export NIX_${role}LDFLAGS+=" -L$1/lib64"
+        export NIX_${role_pre}LDFLAGS+=" -L$1/lib64"
     fi
 
     if [[ -d "$1/lib" ]]; then
-        export NIX_${role}LDFLAGS+=" -L$1/lib"
+        export NIX_${role_pre}LDFLAGS+=" -L$1/lib"
     fi
 }
 
-case $targetOffset in
-    -1)
-        export NIX_BINTOOLS_WRAPPER_@infixSalt@_TARGET_BUILD=1
-        role_pre='BUILD_'
-        role_post='_FOR_BUILD'
-        ;;
-    0)
-        export NIX_BINTOOLS_WRAPPER_@infixSalt@_TARGET_HOST=1
-        role_pre=''
-        role_post=''
-        ;;
-    1)
-        export NIX_BINTOOLS_WRAPPER_@infixSalt@_TARGET_TARGET=1
-        role_pre='TARGET_'
-        role_post='_FOR_TARGET'
-        ;;
-    *)
-        echo "cc-wrapper: used as improper sort of dependency" >2;
-        return 1
-        ;;
-esac
+# See ../setup-hooks/role.bash
+getTargetRole
+getTargetRoleWrapper
 
 addEnvHooks "$targetOffset" bintoolsWrapper_addLDVars
 
diff --git a/pkgs/build-support/cc-wrapper/default.nix b/pkgs/build-support/cc-wrapper/default.nix
index 43cd87fb459..0ea9dd0cb9f 100644
--- a/pkgs/build-support/cc-wrapper/default.nix
+++ b/pkgs/build-support/cc-wrapper/default.nix
@@ -191,7 +191,12 @@ stdenv.mkDerivation {
   propagatedBuildInputs = [ bintools ];
   depsTargetTargetPropagated = extraPackages;
 
-  setupHook = ./setup-hook.sh;
+  wrapperName = "CC_WRAPPER";
+
+  setupHooks = [
+    ../setup-hooks/role.bash
+    ./setup-hook.sh
+  ];
 
   postFixup =
     ''
diff --git a/pkgs/build-support/cc-wrapper/setup-hook.sh b/pkgs/build-support/cc-wrapper/setup-hook.sh
index 29a7306b9b7..17d34c1e1f1 100644
--- a/pkgs/build-support/cc-wrapper/setup-hook.sh
+++ b/pkgs/build-support/cc-wrapper/setup-hook.sh
@@ -66,55 +66,22 @@ set -u
 # over no state, and there's no @-substitutions within, so any redefined
 # function is guaranteed to be exactly the same.
 ccWrapper_addCVars () {
-    # The `depHostOffset` describes how the host platform of the dependencies
-    # are slid relative to the depending package. It is brought into scope of
-    # the environment hook defined as the role of the dependency being applied.
-    case $depHostOffset in
-        -1) local role='BUILD_' ;;
-        0)  local role='' ;;
-        1)  local role='TARGET_' ;;
-        *)  echo "cc-wrapper: Error: Cannot be used with $depHostOffset-offset deps" >2;
-            return 1 ;;
-    esac
+    # See ../setup-hooks/role.bash
+    local role_post role_pre
+    getTargetRoleEnvHook
 
     if [[ -d "$1/include" ]]; then
-        export NIX_${role}CFLAGS_COMPILE+=" ${ccIncludeFlag:--isystem} $1/include"
+        export NIX_${role_pre}CFLAGS_COMPILE+=" ${ccIncludeFlag:--isystem} $1/include"
     fi
 
     if [[ -d "$1/Library/Frameworks" ]]; then
-        export NIX_${role}CFLAGS_COMPILE+=" -F$1/Library/Frameworks"
+        export NIX_${role_pre}CFLAGS_COMPILE+=" -F$1/Library/Frameworks"
     fi
 }
 
-# Since the same cc-wrapper derivation can be depend on in multiple ways, we
-# need to accumulate *each* role (i.e. target platform relative the depending
-# derivation) in which the cc-wrapper derivation is used.
-# `NIX_CC_WRAPPER_@infixSalt@_TARGET_*` tracks this (needs to be an exported env
-# var so can't use fancier data structures).
-#
-# We also need to worry about what role is being added on *this* invocation of
-# setup-hook, which `role` tracks.
-case $targetOffset in
-    -1)
-        export NIX_CC_WRAPPER_@infixSalt@_TARGET_BUILD=1
-        role_pre='BUILD_'
-        role_post='_FOR_BUILD'
-        ;;
-    0)
-        export NIX_CC_WRAPPER_@infixSalt@_TARGET_HOST=1
-        role_pre=''
-        role_post=''
-        ;;
-    1)
-        export NIX_CC_WRAPPER_@infixSalt@_TARGET_TARGET=1
-        role_pre='TARGET_'
-        role_post='_FOR_TARGET'
-        ;;
-    *)
-        echo "cc-wrapper: used as improper sort of dependency" >2;
-        return 1
-        ;;
-esac
+# See ../setup-hooks/role.bash
+getTargetRole
+getTargetRoleWrapper
 
 # We use the `targetOffset` to choose the right env hook to accumulate the right
 # sort of deps (those with that offset).
diff --git a/pkgs/build-support/setup-hooks/role.bash b/pkgs/build-support/setup-hooks/role.bash
new file mode 100644
index 00000000000..6f1c36f5c05
--- /dev/null
+++ b/pkgs/build-support/setup-hooks/role.bash
@@ -0,0 +1,75 @@
+# 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
+#  - $NIX_${role_pre}_SOMETHING
+#  - $NIX_SOMETHING_${role_post}
+
+function getRole() {
+    case $1 in
+        -1)
+            role_pre='BUILD_'
+            role_post='_FOR_BUILD'
+            ;;
+        0)
+            role_pre=''
+            role_post=''
+            ;;
+        1)
+            role_pre='TARGET_'
+            role_post='_FOR_TARGET'
+            ;;
+        *)
+            echo "@name@: used as improper sort of dependency" >2
+            return 1
+            ;;
+    esac
+}
+
+# `hostOffset` describes how the host platform of the package is slid relative
+# to the depending package. `targetOffset` likewise describes the target
+# platform of the package. Both are brought into scope of the setup hook defined
+# for dependency whose setup hook is being processed relative to the package
+# being built.
+
+function getHostRole()   {
+    getRole "$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@_@infixSalt@_TARGET_*` 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@_@infixSalt@_TARGET_BUILD=1
+            ;;
+        0)
+            export NIX_@wrapperName@_@infixSalt@_TARGET_HOST=1
+            ;;
+        1)
+            export NIX_@wrapperName@_@infixSalt@_TARGET_TARGET=1
+            ;;
+        *)
+            echo "@name@: used as improper sort of dependency" >2
+            return 1
+            ;;
+    esac
+}