Move interface so building to action configs

This cl moves the conditional building of interface libraries from LinkCommandLine to action configs and features. It provides link_dynamic_library.sh to keep blaze backwards compatible. The script and related code can be deleted once all crosstools are updated.

RELNOTES: No.

--
MOS_MIGRATED_REVID=135799041

3 files changed, 70 insertions, 0 deletions

diff --git a/tools/cpp/BUILD b/tools/cpp/BUILD
index 50d19a855b..a3c8cbe4a4 100644
--- a/tools/cpp/BUILD
+++ b/tools/cpp/BUILD
@@ -158,3 +158,8 @@ filegroup(
     name = "srcs",
     srcs = glob(["**"]) + ["//tools/cpp/test:srcs"],
 )
+
+filegroup(
+    name = "link_dynamic_library",
+    srcs = ["link_dynamic_library.sh"],
+)
diff --git a/tools/cpp/BUILD.static b/tools/cpp/BUILD.static
index 32a323ad35..6f52c9d0c7 100644
--- a/tools/cpp/BUILD.static
+++ b/tools/cpp/BUILD.static
@@ -94,3 +94,8 @@ filegroup(
         "wrapper/bin/pydir/msvc*",
     ]),
 )
+
+filegroup(
+    name = "link_dynamic_library",
+    srcs = ["link_dynamic_library.sh"],
+)
diff --git a/tools/cpp/link_dynamic_library.sh b/tools/cpp/link_dynamic_library.sh
new file mode 100755
index 0000000000..ae79a80f23
--- /dev/null
+++ b/tools/cpp/link_dynamic_library.sh
@@ -0,0 +1,60 @@
+#!/bin/bash
+#
+# Copyright 2016 The Bazel Authors. 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.
+
+# This script handles interface library generation for dynamic library
+# link action.
+#
+# Bazel can be configured to generate external interface library script
+# to generate interface libraries in CppLinkAction for dynamic libraries.
+# This is not needed on Windows (as the "interface" libraries are
+# generated by default). This script therefore handles the cases when
+# external script is provided, or when no script should be used.
+
+set -eu
+
+E_LINKER_COMMAND_NOT_FOUND=12
+E_INTERFACE_BUILDER_NOT_FOUND=13
+
+# Should generate interface library switch (<yes|no>); if the value is "no",
+# following 3 args are ignored (but must be present)
+GENERATE_INTERFACE_LIBRARY="$1"
+# Tool which can generate interface library from dynamic library file
+INTERFACE_LIBRARY_BUILDER="$2"
+# Dynamic library from which we want to generate interface library
+DYNAMIC_LIBRARY="$3"
+# Resulting interface library
+INTERFACE_LIBRARY="$4"
+# The command used to generate the dynamic library
+LINKER_COMMAND="$5"
+
+shift 5
+
+if [ ! -e "$LINKER_COMMAND" ]; then
+  echo "Linker command ($LINKER_COMMAND) not found." 1>&2;
+  exit "$E_LINKER_COMMAND_NOT_FOUND"
+fi
+
+if [ "no" == "$GENERATE_INTERFACE_LIBRARY" ]; then
+    INTERFACE_GENERATION=:
+else
+    if [ ! -e "$INTERFACE_LIBRARY_BUILDER" ]; then
+      echo "Interface library builder ($INTERFACE_LIBRARY_BUILDER) not found." 1>&2;
+      exit "$E_INTERFACE_BUILDER_NOT_FOUND"
+    fi
+    INTERFACE_GENERATION="${INTERFACE_LIBRARY_BUILDER} ${DYNAMIC_LIBRARY} ${INTERFACE_LIBRARY}"
+fi
+
+${LINKER_COMMAND} "$@" && ${INTERFACE_GENERATION}