Switch to blueprint's microfactory

Bug: 63720725
Test: m -j nothing
Test: mkdir o; ../bootstrap.bash; ./soong
Change-Id: Id1f8312678f36afd08b49f8511fec3e6e5ba8de2
diff --git a/scripts/microfactory.bash b/scripts/microfactory.bash
new file mode 100644
index 0000000..65ba55d
--- /dev/null
+++ b/scripts/microfactory.bash
@@ -0,0 +1,66 @@
+# Copyright 2017 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Set of utility functions to build and run go code with microfactory
+#
+# Inputs:
+#  ${TOP}: The top of the android source tree
+#  ${OUT_DIR}: The output directory location (defaults to ${TOP}/out)
+#  ${OUT_DIR_COMMON_BASE}: Change the default out directory to
+#    ${OUT_DIR_COMMON_BASE}/$(basename ${TOP})
+
+# Ensure GOROOT is set to the in-tree version.
+case $(uname) in
+    Linux)
+        export GOROOT="${TOP}/prebuilts/go/linux-x86/"
+        ;;
+    Darwin)
+        export GOROOT="${TOP}/prebuilts/go/darwin-x86/"
+        ;;
+    *) echo "unknown OS:" $(uname) >&2 && exit 1;;
+esac
+
+# Find the output directory
+function getoutdir
+{
+    local out_dir="${OUT_DIR-}"
+    if [ -z "${out_dir}" ]; then
+        if [ "${OUT_DIR_COMMON_BASE-}" ]; then
+            out_dir="${OUT_DIR_COMMON_BASE}/$(basename ${TOP})"
+        else
+            out_dir="out"
+        fi
+    fi
+    if [[ "${out_dir}" != /* ]]; then
+        out_dir="${TOP}/${out_dir}"
+    fi
+    echo "${out_dir}"
+}
+
+# Bootstrap microfactory from source if necessary and use it to build the
+# requested binary.
+#
+# Arguments:
+#  $1: name of the requested binary
+#  $2: package name
+function soong_build_go
+{
+    BUILDDIR=$(getoutdir) \
+      SRCDIR=${TOP} \
+      BLUEPRINTDIR=${TOP}/build/blueprint \
+      EXTRA_ARGS="-pkg-path android/soong=${TOP}/build/soong" \
+      build_go $@
+}
+
+source ${TOP}/build/blueprint/microfactory/microfactory.bash