Copy osx_cc_wrapper.sh.tpl from bazel

This is no longer used in bazel so we should just own it. This copies
over the relevant shell test too.

crosstool/osx_cc_configure.bzl

@@ -163,7 +163,7 @@ def configure_osx_toolchain(repository_ctx):
     # https://github.com/bazelbuild/bazel/blob/ab71a1002c9c53a8061336e40f91204a2a32c38e/tools/cpp/lib_cc_configure.bzl#L17-L38
     # for more info
     xcode_locator = Label("@bazel_tools//tools/osx:xcode_locator.m")
-    osx_cc_wrapper = Label("@bazel_tools//tools/cpp:osx_cc_wrapper.sh.tpl")
+    osx_cc_wrapper = Label("@build_bazel_apple_support//crosstool:osx_cc_wrapper.sh.tpl")
     xcrunwrapper = Label("@build_bazel_apple_support//crosstool:xcrunwrapper.sh")
     libtool = Label("@build_bazel_apple_support//crosstool:libtool.sh")
     make_hashed_objlist = Label("@build_bazel_apple_support//crosstool:make_hashed_objlist.py")

crosstool/osx_cc_wrapper.sh.tpl

@@ -0,0 +1,138 @@
+#!/bin/bash
+#
+# Copyright 2015 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.
+#
+# OS X relpath is not really working. This is a wrapper script around gcc
+# to simulate relpath behavior.
+#
+# This wrapper uses install_name_tool to replace all paths in the binary
+# (bazel-out/.../path/to/original/library.so) by the paths relative to
+# the binary. It parses the command line to behave as rpath is supposed
+# to work.
+#
+# See https://blogs.oracle.com/dipol/entry/dynamic_libraries_rpath_and_mac
+# on how to set those paths for Mach-O binaries.
+#
+set -eu
+
+LIBS=
+LIB_PATHS=
+LIB_DIRS=
+RPATHS=
+OUTPUT=
+
+function parse_option() {
+    local -r opt="$1"
+    if [[ "${OUTPUT}" = "1" ]]; then
+        OUTPUT=$opt
+    elif [[ "$opt" =~ ^-l(.*)$ ]]; then
+        LIBS="${BASH_REMATCH[1]} $LIBS"
+    elif [[ "$opt" =~ ^(.*)\.so$ ]]; then
+        LIB_PATHS="${opt} $LIB_PATHS"
+    elif [[ "$opt" =~ ^(.*)\.dylib$ ]]; then
+        LIB_PATHS="${opt} $LIB_PATHS"
+    elif [[ "$opt" =~ ^-L(.*)$ ]]; then
+        LIB_DIRS="${BASH_REMATCH[1]} $LIB_DIRS"
+    elif [[ "$opt" =~ ^\@loader_path/(.*)$ ]]; then
+        RPATHS="${BASH_REMATCH[1]} ${RPATHS}"
+    elif [[ "$opt" = "-o" ]]; then
+        # output is coming
+        OUTPUT=1
+    fi
+}
+
+# let parse the option list
+for i in "$@"; do
+    if [[ "$i" = @* && -r "${i:1}" ]]; then
+        while IFS= read -r opt
+        do
+            parse_option "$opt"
+        done < "${i:1}" || exit 1
+    else
+        parse_option "$i"
+    fi
+done
+
+# Set-up the environment
+%{env}
+
+# Call the C++ compiler
+%{cc} "$@"
+
+# Generate an empty file if header processing succeeded.
+if [[ "${OUTPUT}" == *.h.processed ]]; then
+  echo -n > "${OUTPUT}"
+fi
+
+function get_library_path() {
+    for libdir in ${LIB_DIRS}; do
+        if [ -f ${libdir}/lib$1.so ]; then
+            echo "${libdir}/lib$1.so"
+        elif [ -f ${libdir}/lib$1.dylib ]; then
+            echo "${libdir}/lib$1.dylib"
+        fi
+    done
+}
+
+# A convenient method to return the actual path even for non symlinks
+# and multi-level symlinks.
+function get_realpath() {
+    local previous="$1"
+    local next=$(readlink "${previous}")
+    while [ -n "${next}" ]; do
+        previous="${next}"
+        next=$(readlink "${previous}")
+    done
+    echo "${previous}"
+}
+
+# Get the path of a lib inside a tool
+function get_otool_path() {
+    # the lib path is the path of the original lib relative to the workspace
+    get_realpath $1 | sed 's|^.*/bazel-out/|bazel-out/|'
+}
+
+function call_install_name() {
+    /usr/bin/xcrun install_name_tool -change $(get_otool_path "$1") \
+        "@loader_path/$2/$3" "${OUTPUT}"
+}
+
+# Do replacements in the output
+for rpath in ${RPATHS}; do
+    for lib in ${LIBS}; do
+        unset libname
+        if [ -f "$(dirname ${OUTPUT})/${rpath}/lib${lib}.so" ]; then
+            libname="lib${lib}.so"
+        elif [ -f "$(dirname ${OUTPUT})/${rpath}/lib${lib}.dylib" ]; then
+            libname="lib${lib}.dylib"
+        fi
+        # ${libname-} --> return $libname if defined, or undefined otherwise. This is to make
+        # this set -e friendly
+        if [[ -n "${libname-}" ]]; then
+            libpath=$(get_library_path ${lib})
+            if [ -n "${libpath}" ]; then
+                call_install_name "${libpath}" "${rpath}" "${libname}"
+            fi
+        fi
+    done
+    for libpath in ${LIB_PATHS}; do
+        if [ -f "$libpath" ]; then
+            libname=$(basename "$libpath")
+            if [ -f "$(dirname ${OUTPUT})/${rpath}/${libname}" ]; then
+                call_install_name "${libpath}" "${rpath}" "${libname}"
+            fi
+        fi
+    done
+done

test/rpaths/BUILD

@@ -0,0 +1,34 @@
+load("@rules_shell//shell:sh_test.bzl", "sh_test")
+
+cc_library(
+    name = "foo",
+    srcs = ["foo.cc"],
+)
+
+cc_binary(
+    name = "libbar.so",
+    srcs = ["bar.cc"],
+    linkshared = True,
+)
+
+cc_binary(
+    name = "libbaz.dylib",
+    srcs = ["baz.cc"],
+    linkshared = True,
+)
+
+cc_test(
+    name = "test",
+    srcs = [
+        "test.cc",
+        ":libbar.so",
+        ":libbaz.dylib",
+    ],
+    deps = [":foo"],
+)
+
+sh_test(
+    name = "test-portable",
+    srcs = ["test-portable.sh"],
+    data = [":test"],
+)

test/rpaths/bar.cc

@@ -0,0 +1 @@
+int bar() { return 12; }

test/rpaths/baz.cc

@@ -0,0 +1 @@
+int baz() { return 42; }

test/rpaths/foo.cc

@@ -0,0 +1 @@
+int foo() { return 2; }

test/rpaths/test-portable.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+set -euo pipefail
+
+# Without valid rpaths the binary will only work from a specific PWD
+
+./test/rpaths/test
+cd ./test
+./rpaths/test
+cd ./rpaths
+./test

test/rpaths/test.cc

@@ -0,0 +1,11 @@
+int foo();
+int bar();
+int baz();
+int main() {
+  int result = foo() + bar() + baz();
+  if (result == 56) {
+    return 0;
+  } else {
+    return result;
+  }
+}