adding multi rmw implementation infrastructure

rcl/CMakeLists.txt

@@ -57,6 +57,7 @@ endmacro()
 
 call_for_each_rmw_implementation(target GENERATE_DEFAULT)
 
+ament_export_dependencies(ament_cmake)
 ament_export_dependencies(rcl_interfaces)
 ament_export_dependencies(rmw)
 ament_export_dependencies(rmw_implementation)
@@ -73,7 +74,14 @@ if(AMENT_ENABLE_TESTING)
   add_subdirectory(test)
 endif()
 
-ament_package()
+ament_package(
+  CONFIG_EXTRAS rcl-extras.cmake
+)
+
+install(
+  DIRECTORY cmake
+  DESTINATION share/${PROJECT_NAME}
+)
 
 install(
   DIRECTORY include/

rcl/cmake/get_rcl_information.cmake

@@ -0,0 +1,90 @@
+# Copyright 2016 Open Source Robotics Foundation, Inc.
+#
+# 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.
+
+#
+# Get all information about rcl for a specific RMW implementation.
+#
+# It sets the common variables _DEFINITIONS, _INCLUDE_DIRS and _LIBRARIES
+# with the given prefix.
+#
+# :param rmw_implementation: the RMW implementation name
+# :type target: string
+# :param var_prefix: the prefix of all output variable names
+# :type var_prefix: string
+#
+# Copy/pasted from rclcpp/cmake/get_rclcpp_information.cmake.
+# Code duplication is evil. Don't do this at home, kids.
+
+macro(get_rcl_information rmw_implementation var_prefix)
+  # pretend to be a "package"
+  # so that the variables can be used by various functions / macros
+  set(${var_prefix}_FOUND TRUE)
+
+  # include directories
+  normalize_path(${var_prefix}_INCLUDE_DIRS "${rcl_DIR}/../../../include")
+
+  # libraries
+  set(_libs)
+  # search for library relative to this CMake file
+  set(_library_target "rcl")
+  get_available_rmw_implementations(_rmw_impls)
+  list(LENGTH _rmw_impls _rmw_impls_length)
+  if(_rmw_impls_length GREATER 1)
+    set(_library_target "${_library_target}__${rmw_implementation}")
+  endif()
+  set(_lib "NOTFOUND")
+  find_library(
+    _lib NAMES "${_library_target}"
+    PATHS "${rcl_DIR}/../../../lib"
+    NO_DEFAULT_PATH NO_CMAKE_FIND_ROOT_PATH
+  )
+  if(NOT _lib)
+    # warn about not existing library and ignore it
+    message(WARNING "Package 'rcl' doesn't contain the library '${_library_target}'")
+  elseif(NOT IS_ABSOLUTE "${_lib}")
+    # the found library must be an absolute path
+    message(FATAL_ERROR "Package 'rcl' found the library '${_library_target}' at '${_lib}' which is not an absolute path")
+  elseif(NOT EXISTS "${_lib}")
+    # the found library must exist
+    message(FATAL_ERROR "Package 'rcl' found the library '${_lib}' which doesn't exist")
+  else()
+    list(APPEND _libs "${_lib}")
+  endif()
+
+  # dependencies
+  set(_exported_dependencies
+    "rcl_interfaces"
+    "rmw"
+    "${rmw_implementation}"
+    "rosidl_generator_c")
+  set(${var_prefix}_DEFINITIONS)
+  foreach(_dep ${_exported_dependencies})
+    if(NOT ${_dep}_FOUND)
+      find_package("${_dep}" QUIET REQUIRED)
+    endif()
+    if(${_dep}_DEFINITIONS)
+      list_append_unique(${var_prefix}_DEFINITIONS "${${_dep}_DEFINITIONS}")
+    endif()
+    if(${_dep}_INCLUDE_DIRS)
+      list_append_unique(${var_prefix}_INCLUDE_DIRS "${${_dep}_INCLUDE_DIRS}")
+    endif()
+    if(${_dep}_LIBRARIES)
+      list(APPEND _libs "${${_dep}_LIBRARIES}")
+    endif()
+  endforeach()
+  if(_libs)
+    ament_libraries_deduplicate(_libs "${_libs}")
+  endif()
+  set(${var_prefix}_LIBRARIES "${_libs}")
+endmacro()

rcl/package.xml

@@ -18,6 +18,7 @@
   <build_export_depend>rcl_interfaces</build_export_depend>
   <build_export_depend>rosidl_generator_c</build_export_depend>
 
+  <exec_depend>ament_cmake</exec_depend>
   <exec_depend>rosidl_default_runtime</exec_depend>
 
   <depend>rmw_implementation</depend>

rcl/rcl-extras.cmake

@@ -0,0 +1,17 @@
+# Copyright 2016 Open Source Robotics Foundation, Inc.
+#
+# 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.
+
+# copied from rcl/rcl-extras.cmake
+
+include("${rcl_DIR}/get_rcl_information.cmake")