[build-toolchain] Add the ability to specify a prefix to prepend to the specific toolchain preset invoked.

Author: gottesmm

utils/build-toolchain

@@ -32,6 +32,9 @@ function usage() {
   echo "--preset-file"
   echo "load build-script presets from the specified file"
   echo ""
+  echo "--preset-prefix"
+  echo "Customize the preset invoked by prepending a prefix"
+  echo ""
 }
 
 RESULT_DIR=$PWD
@@ -42,6 +45,7 @@ DISTCC_FLAG=
 DRY_RUN=
 BUNDLE_PREFIX=
 PRESET_FILE_FLAGS=
+PRESET_PREFIX=
 case $(uname -s) in
   Darwin)
     SWIFT_PACKAGE=buildbot_osx_package,no_test
@@ -77,6 +81,10 @@ while [ $# -ne 0 ]; do
     --preset-file)
       shift
       PRESET_FILE_FLAGS="${PRESET_FILE_FLAGS} --preset-file=$1"
+  ;;
+    --preset-prefix)
+      shift
+      PRESET_PREFIX="$1"
   ;;
   -h|--help)
     usage
@@ -125,7 +133,7 @@ DRY_RUN="${DRY_RUN}"
 DISTCC_FLAG="${DISTCC_FLAG}"
 PRESET_FILE_FLAGS="${PRESET_FILE_FLAGS}"
 
-./utils/build-script ${DRY_RUN} ${DISTCC_FLAG} ${PRESET_FILE_FLAGS} --preset="${SWIFT_PACKAGE}" \
+./utils/build-script ${DRY_RUN} ${DISTCC_FLAG} ${PRESET_FILE_FLAGS} --preset="${PRESET_PREFIX}${SWIFT_PACKAGE}" \
         install_destdir="${SWIFT_INSTALL_DIR}" \
         installable_package="${SWIFT_INSTALLABLE_PACKAGE}" \
         install_toolchain_dir="${SWIFT_TOOLCHAIN_DIR}" \