Initial set of files.

The make install target is not working for .proto files, but otherwise
it seems to work.

1 files changed, 286 insertions, 0 deletions

diff --git a/cmake/CompileProtos.cmake b/cmake/CompileProtos.cmake
new file mode 100644
index 000000000000..a01a90b825e8
--- /dev/null
+++ b/cmake/CompileProtos.cmake
@@ -0,0 +1,286 @@
+# ~~~
+# Copyright 2019 Google LLC
+#
+# 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.
+# ~~~
+
+# Introduce a new TARGET property to associate proto files with a target.
+#
+# We use a function to define the property so it can be called multiple times
+# without introducing the property over and over.
+function (google_cloud_cpp_add_protos_property)
+    set_property(TARGET
+                 PROPERTY PROTO_SOURCES
+                          BRIEF_DOCS
+                          "The list of .proto files for a target."
+                          FULL_DOCS
+                          "List of .proto files specified for a target.")
+endfunction ()
+
+# Generate C++ for .proto files preserving the directory hierarchy
+#
+# Receives a list of `.proto` file names and (a) creates the runs to convert
+# these files to `.pb.h` and `.pb.cc` output files, (b) returns the list of
+# `.pb.cc` files and `.pb.h` files in @p HDRS, and (c) creates the list of files
+# preserving the directory hierarchy, such that if a `.proto` file says:
+#
+# import "foo/bar/baz.proto"
+#
+# the resulting C++ code says:
+#
+# #include <foo/bar/baz.pb.h>
+#
+# Use the `PROTO_PATH` option to provide one or more directories to search for
+# proto files in the import.
+#
+# @par Example
+#
+# google_cloud_cpp_generate_proto( MY_PB_FILES "foo/bar/baz.proto"
+# "foo/bar/qux.proto" PROTO_PATH_DIRECTORIES "another/dir/with/protos")
+#
+# Note that `protoc` the protocol buffer compiler requires your protos to be
+# somewhere in the search path defined by the `--proto_path` (aka -I) options.
+# For example, if you want to generate the `.pb.{h,cc}` files for
+# `foo/bar/baz.proto` then the directory containing `foo` must be in the search
+# path.
+function (google_cloud_cpp_generate_proto SRCS)
+    cmake_parse_arguments(_opt "" "" "PROTO_PATH_DIRECTORIES" ${ARGN})
+    if (NOT _opt_UNPARSED_ARGUMENTS)
+        message(SEND_ERROR "Error: google_cloud_cpp_generate_proto() called"
+                           " without any proto files")
+        return()
+    endif ()
+
+    # Build the list of `--proto_path` options. Use the absolute path for each
+    # option given, and do not include any path more than once.
+    set(protobuf_include_path)
+    foreach (dir ${_opt_PROTO_PATH_DIRECTORIES})
+        get_filename_component(absolute_path ${dir} ABSOLUTE)
+        list(FIND protobuf_include_path "${absolute_path}"
+                  already_in_search_path)
+        if (${already_in_search_path} EQUAL -1)
+            list(APPEND protobuf_include_path "--proto_path" "${absolute_path}")
+        endif ()
+    endforeach ()
+
+    set(${SRCS})
+    foreach (filename ${_opt_UNPARSED_ARGUMENTS})
+        get_filename_component(file_directory "${filename}" DIRECTORY)
+        # This gets the filename without the extension, analogous to $(basename
+        # "${filename}" .proto)
+        get_filename_component(file_stem "${filename}" NAME_WE)
+
+        # Strip all the prefixes in ${_opt_PROTO_PATH_DIRECTORIES} from the
+        # source proto directory
+        set(D "${file_directory}")
+        if (DEFINED _opt_PROTO_PATH_DIRECTORIES)
+            foreach (P ${_opt_PROTO_PATH_DIRECTORIES})
+                string(REGEX
+                       REPLACE "^${P}"
+                               ""
+                               T
+                               "${D}")
+                set(D ${T})
+            endforeach ()
+        endif ()
+        set(pb_cc "${CMAKE_CURRENT_BINARY_DIR}/${D}/${file_stem}.pb.cc")
+        set(pb_h "${CMAKE_CURRENT_BINARY_DIR}/${D}/${file_stem}.pb.h")
+        list(APPEND ${SRCS} "${pb_cc}" "${pb_h}")
+        add_custom_command(
+            OUTPUT "${pb_cc}" "${pb_h}"
+            COMMAND $<TARGET_FILE:protobuf::protoc>
+                    ARGS
+                    --cpp_out "${CMAKE_CURRENT_BINARY_DIR}"
+                              ${protobuf_include_path} "${filename}"
+            DEPENDS "${filename}" protobuf::protoc
+            COMMENT "Running C++ protocol buffer compiler on ${filename}"
+            VERBATIM)
+    endforeach ()
+
+    set_source_files_properties(${${SRCS}} PROPERTIES GENERATED TRUE)
+    set(${SRCS} ${${SRCS}} PARENT_SCOPE)
+endfunction ()
+
+# Generate gRPC C++ files from .proto files preserving the directory hierarchy.
+#
+# Receives a list of `.proto` file names and (a) creates the runs to convert
+# these files to `.grpc.pb.h` and `.grpc.pb.cc` output files, (b) returns the
+# list of `.grpc.pb.cc` and `.pb.h` files in @p SRCS, and (c) creates the list
+# of files preserving the directory hierarchy, such that if a `.proto` file says
+#
+# import "foo/bar/baz.proto"
+#
+# the resulting C++ code says:
+#
+# #include <foo/bar/baz.pb.h>
+#
+# Use the `PROTO_PATH` option to provide one or more directories to search for
+# proto files in the import.
+#
+# @par Example
+#
+# google_cloud_cpp_generate_grpc( MY_GRPC_PB_FILES "foo/bar/baz.proto"
+# "foo/bar/qux.proto" PROTO_PATH_DIRECTORIES "another/dir/with/protos")
+#
+# Note that `protoc` the protocol buffer compiler requires your protos to be
+# somewhere in the search path defined by the `--proto_path` (aka -I) options.
+# For example, if you want to generate the `.pb.{h,cc}` files for
+# `foo/bar/baz.proto` then the directory containing `foo` must be in the search
+# path.
+function (google_cloud_cpp_generate_grpcpp SRCS)
+    cmake_parse_arguments(_opt "" "" "PROTO_PATH_DIRECTORIES" ${ARGN})
+    if (NOT _opt_UNPARSED_ARGUMENTS)
+        message(
+            SEND_ERROR "Error: google_cloud_cpp_generate_grpc() called without"
+                       " any proto files")
+        return()
+    endif ()
+
+    # Build the list of `--proto_path` options. Use the absolute path for each
+    # option given, and do not include any path more than once.
+    set(protobuf_include_path)
+    foreach (dir ${_opt_PROTO_PATH_DIRECTORIES})
+        get_filename_component(absolute_path ${dir} ABSOLUTE)
+        list(FIND protobuf_include_path "${absolute_path}"
+                  already_in_search_path)
+        if (${already_in_search_path} EQUAL -1)
+            list(APPEND protobuf_include_path "--proto_path" "${absolute_path}")
+        endif ()
+    endforeach ()
+
+    set(${SRCS})
+    foreach (filename ${_opt_UNPARSED_ARGUMENTS})
+        get_filename_component(file_directory "${filename}" DIRECTORY)
+        # This gets the filename without the extension, analogous to $(basename
+        # "${filename}" .proto)
+        get_filename_component(file_stem "${filename}" NAME_WE)
+
+        # Strip all the prefixes in ${_opt_PROTO_PATH_DIRECTORIES} from the
+        # source proto directory
+        set(D "${file_directory}")
+        if (DEFINED _opt_PROTO_PATH_DIRECTORIES)
+            foreach (P ${_opt_PROTO_PATH_DIRECTORIES})
+                string(REGEX
+                       REPLACE "^${P}"
+                               ""
+                               T
+                               "${D}")
+                set(D ${T})
+            endforeach ()
+        endif ()
+        set(grpc_pb_cc
+            "${CMAKE_CURRENT_BINARY_DIR}/${D}/${file_stem}.grpc.pb.cc")
+        set(grpc_pb_h "${CMAKE_CURRENT_BINARY_DIR}/${D}/${file_stem}.grpc.pb.h")
+        list(APPEND ${SRCS} "${grpc_pb_cc}" "${grpc_pb_h}")
+        add_custom_command(
+            OUTPUT "${grpc_pb_cc}" "${grpc_pb_h}"
+            COMMAND
+                $<TARGET_FILE:protobuf::protoc>
+                ARGS
+                --plugin=protoc-gen-grpc=$<TARGET_FILE:gRPC::grpc_cpp_plugin>
+                    "--grpc_out=${CMAKE_CURRENT_BINARY_DIR}"
+                    "--cpp_out=${CMAKE_CURRENT_BINARY_DIR}"
+                    ${protobuf_include_path} "${filename}"
+            DEPENDS "${filename}" protobuf::protoc gRPC::grpc_cpp_plugin
+            COMMENT "Running gRPC C++ protocol buffer compiler on ${filename}"
+            VERBATIM)
+    endforeach ()
+
+    set_source_files_properties(${${SRCS}} PROPERTIES GENERATED TRUE)
+    set(${SRCS} ${${SRCS}} PARENT_SCOPE)
+endfunction ()
+
+include(GNUInstallDirs)
+
+# Install headers for a C++ proto library.
+function (google_cloud_cpp_install_proto_library_headers target)
+    get_target_property(target_sources ${target} SOURCES)
+    foreach (header ${target_sources})
+        # Skip anything that is not a header file.
+        if (NOT "${header}" MATCHES "\\.h$")
+            continue()
+        endif ()
+        string(REPLACE "${CMAKE_CURRENT_BINARY_DIR}/"
+                       ""
+                       relative
+                       "${header}")
+        get_filename_component(dir "${relative}" DIRECTORY)
+        install(FILES "${header}" DESTINATION
+                      "${CMAKE_INSTALL_INCLUDEDIR}/${dir}")
+    endforeach ()
+endfunction ()
+
+# Install protos for a C++ proto library.
+function (google_cloud_cpp_install_proto_library_protos target)
+    get_target_property(target_protos ${target} PROTO_SOURCES)
+    foreach (header ${target_protos})
+        # Skip anything that is not a header file.
+        if (NOT "${header}" MATCHES "\\.proto$")
+            continue()
+        endif ()
+        string(REPLACE "${CMAKE_CURRENT_BINARY_DIR}/"
+                       ""
+                       relative
+                       "${header}")
+        get_filename_component(dir "${relative}" DIRECTORY)
+        # This is modeled after the Protobuf library, it installs the basic
+        # protos (think google/protobuf/any.proto) in the include directory for
+        # C/C++ code. :shrug:
+        install(FILES "${header}" DESTINATION
+                      "${CMAKE_INSTALL_INCLUDEDIR}/${dir}")
+    endforeach ()
+endfunction ()
+
+function (google_cloud_cpp_proto_library libname)
+    cmake_parse_arguments(_opt "" "" "PROTO_PATH_DIRECTORIES" ${ARGN})
+    if (NOT _opt_UNPARSED_ARGUMENTS)
+        message(SEND_ERROR "Error: google_cloud_cpp_proto_library() called"
+                           " without any proto files")
+        return()
+    endif ()
+
+    google_cloud_cpp_generate_proto(proto_sources
+                                    ${_opt_UNPARSED_ARGUMENTS}
+                                    PROTO_PATH_DIRECTORIES
+                                    ${_opt_PROTO_PATH_DIRECTORIES})
+
+    add_library(${libname} ${proto_sources})
+    set_property(TARGET ${libname}
+                 PROPERTY PROTO_SOURCES ${_opt_UNPARSED_ARGUMENTS})
+    target_link_libraries(${libname}
+                          PUBLIC gRPC::grpc++ gRPC::grpc protobuf::libprotobuf)
+    target_include_directories(
+        ${libname}
+        PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}>
+               $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}>
+               $<INSTALL_INTERFACE:include>)
+endfunction ()
+
+function (google_cloud_cpp_grpcpp_library libname)
+    cmake_parse_arguments(_opt "" "" "PROTO_PATH_DIRECTORIES" ${ARGN})
+    if (NOT _opt_UNPARSED_ARGUMENTS)
+        message(SEND_ERROR "Error: google_cloud_cpp_proto_library() called"
+                           " without any proto files")
+        return()
+    endif ()
+
+    google_cloud_cpp_generate_grpcpp(grpcpp_sources
+                                     ${_opt_UNPARSED_ARGUMENTS}
+                                     PROTO_PATH_DIRECTORIES
+                                     ${_opt_PROTO_PATH_DIRECTORIES})
+    google_cloud_cpp_proto_library(${libname}
+                                   ${_opt_UNPARSED_ARGUMENTS}
+                                   PROTO_PATH_DIRECTORIES
+                                   ${_opt_PROTO_PATH_DIRECTORIES})
+    target_sources(${libname} PRIVATE ${grpcpp_sources})
+endfunction ()