added default Linux UE toolchain directory (#558)

Instead of forcing user to specify a suitable directory for the UE toolchain, we offer a default which matches what the Github runners use and which is also covered by the root `.gitignore` file

2 files changed, 22 insertions, 14 deletions

diff --git a/scripts/ue_build_linux/get_ue_toolchain.sh b/scripts/ue_build_linux/get_ue_toolchain.sh
index dab87cf88..c2538b09a 100755
--- a/scripts/ue_build_linux/get_ue_toolchain.sh
+++ b/scripts/ue_build_linux/get_ue_toolchain.sh
@@ -5,21 +5,23 @@ ZEN_ROOT=$(realpath $SCRIPT_DIR/../..)
 
 die() { echo "ERROR: $1"; exit; }
 
-if [ -z $1 ]; then
+toolchain_dir="${1:-${ZEN_ROOT}/.tmp-ue-toolchain}"
+
+if [[ $toolchain_dir == "--help" ]]; then
 	echo "usage: $(basename ${BASH_SOURCE[0]}) <output_dir>"
 	exit
 fi
 
-if [ -e $1 ]; then
-	rmdir $1
+if [ -e $toolchain_dir ]; then
+	rmdir $toolchain_dir
 	if [ $? -gt 0 ]; then
-		die "$1 is not empty"
+		die "$toolchain_dir is not empty"
 		exit
 	fi
 fi
 
-mkdir -p $1
-cd $1
+mkdir -p $toolchain_dir
+cd $toolchain_dir
 
 mkdir -p tmp
 cd tmp
@@ -27,7 +29,7 @@ cd tmp
 CLANG_VERSION=v25_clang-18.1.0-rockylinux8
 TOOLCHAIN_PLATFORM=x86_64-unknown-linux-gnu
 
-echo "Fetching UE toolchain $CLANG_VERSION..."
+echo "Fetching UE toolchain $CLANG_VERSION into '$toolchain_dir'..."
 wget -q --show-progress http://cdn.unrealengine.com/Toolchain_Linux/native-linux-$CLANG_VERSION.tar.gz
 
 echo "Extracting toolchain $TOOLCHAIN_PLATFORM..."
diff --git a/scripts/ue_build_linux/ue_build.sh b/scripts/ue_build_linux/ue_build.sh
index 4613dd5ec..690f9f661 100755
--- a/scripts/ue_build_linux/ue_build.sh
+++ b/scripts/ue_build_linux/ue_build.sh
@@ -1,22 +1,28 @@
 #!/bin/bash
 
+SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
+ZEN_ROOT=$(realpath $SCRIPT_DIR/../..)
+
 die() { echo ERROR: $1; exit 1; }
 
-# Validate input
-if [ -z $1 ]; then
-	echo "usage: $0 <ue_toolchain_dir>"
-	exit 1
+if [[ $1 == "--help" ]]; then
+	echo "usage: $0 <ue_toolchain_dir> (defaults to ${ZEN_ROOT}/.tmp-ue-toolchain)"
+	exit
 fi
 
-if ! [ -d $1 ]; then
+toolchain_dir="${1:-${ZEN_ROOT}/.tmp-ue-toolchain}"
+
+# Validate input
+
+if ! [ -d $toolchain_dir ]; then
 	die "$1 is not a directory"
 fi
 
-if ! [ -e $1/bin/clang++ ]; then
+if ! [ -e $toolchain_dir/bin/clang++ ]; then
 	die "$1/bin/clang++ does not exist"
 fi
 
-export UE_TOOLCHAIN_DIR=$(realpath $1)
+export UE_TOOLCHAIN_DIR=$(realpath $toolchain_dir)
 export CC="clang"
 export CXX="clang++"
 export LD="clang++"