Merge topic 'FindProtobuf-upstream-options'

f784ef75a7 FindProtobuf: Add documentation for protobuf_generate()
cd3ff53c88 FindProtobuf: Add DEPENDENCIES to protobuf_generate
31adc11030 FindProtobuf: Add PLUGIN_OPTIONS and PROTOC_OPTIONS to protobuf_generate

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: buildbot <buildbot@kitware.com>
Merge-request: !8601

1 files changed, 111 insertions, 12 deletions

diff --git a/Modules/FindProtobuf.cmake b/Modules/FindProtobuf.cmake
index b046fcc..3455412 100644
--- a/Modules/FindProtobuf.cmake
+++ b/Modules/FindProtobuf.cmake
@@ -136,15 +136,95 @@ Example:
     Variable to define with autogenerated Python files
   ``ARGN``
     ``.proto`` files
+
+.. command:: protobuf_generate
+
+  .. versionadded:: 3.13
+
+  Automatically generate source files from ``.proto`` schema files at build time::
+
+    protobuf_generate (
+        TARGET <target>
+        [LANGUAGE <lang>]
+        [OUT_VAR <out_var>]
+        [EXPORT_MACRO <macro>]
+        [PROTOC_OUT_DIR <dir>]
+        [PLUGIN <plugin>]
+        [PLUGIN_OPTIONS <plugin_options>]
+        [DEPENDENCIES <depends]
+        [PROTOS <protobuf_files>]
+        [IMPORT_DIRS <dirs>]
+        [GENERATE_EXTENSIONS <extensions>]
+        [PROTOC_OPTIONS <protoc_options>]
+        [APPEND_PATH])
+
+  ``APPEND_PATH``
+    A flag that causes the base path of all proto schema files to be added to
+    ``IMPORT_DIRS``.
+  ``LANGUAGE``
+    A single value: cpp or python. Determines what kind of source files are
+    being generated. Defaults to cpp.
+  ``OUT_VAR``
+    Name of a CMake variable that will be filled with the paths to the generated
+    source files.
+  ``EXPORT_MACRO``
+    Name of a macro that is applied to all generated Protobuf message classes
+    and extern variables. It can, for example, be used to declare DLL exports.
+  ``PROTOC_OUT_DIR``
+    Output directory of generated source files. Defaults to ``CMAKE_CURRENT_BINARY_DIR``.
+  ``PLUGIN``
+    .. versionadded:: 3.21
+
+    An optional plugin executable. This could, for example, be the path to
+    ``grpc_cpp_plugin``.
+  ``PLUGIN_OPTIONS``
+    .. versionadded:: 3.28
+
+    Additional options provided to the plugin, such as ``generate_mock_code=true``
+    for the gRPC cpp plugin.
+  ``DEPENDENCIES``
+    .. versionadded:: 3.28
+
+    Arguments forwarded to the ``DEPENDS`` of the underlying ``add_custom_command``
+    invocation.
+  ``TARGET``
+    CMake target that will have the generated files added as sources.
+  ``PROTOS``
+    List of proto schema files. If omitted, then every source file ending in *proto* of ``TARGET`` will be used.
+  ``IMPORT_DIRS``
+    A common parent directory for the schema files. For example, if the schema file is
+    ``proto/helloworld/helloworld.proto`` and the import directory ``proto/`` then the
+    generated files are ``${PROTOC_OUT_DIR}/helloworld/helloworld.pb.h`` and
+    ``${PROTOC_OUT_DIR}/helloworld/helloworld.pb.cc``.
+  ``GENERATE_EXTENSIONS``
+    If LANGUAGE is omitted then this must be set to the extensions that protoc generates.
+  ``PROTOC_OPTIONS``
+    .. versionadded:: 3.28
+
+    Additional arguments that are forwarded to protoc.
+
+  Example::
+
+    find_package(gRPC CONFIG REQUIRED)
+    find_package(Protobuf REQUIRED)
+    add_library(ProtoTest Test.proto)
+    target_link_libraries(ProtoTest PUBLIC gRPC::grpc++)
+    protobuf_generate(TARGET ProtoTest)
+    protobuf_generate(
+        TARGET ProtoTest
+        LANGUAGE grpc
+        PLUGIN protoc-gen-grpc=$<TARGET_FILE:gRPC::grpc_cpp_plugin>
+        PLUGIN_OPTIONS generate_mock_code=true
+        GENERATE_EXTENSIONS .grpc.pb.h .grpc.pb.cc)
 #]=======================================================================]
 
 function(protobuf_generate)
   set(_options APPEND_PATH DESCRIPTORS)
-  set(_singleargs LANGUAGE OUT_VAR EXPORT_MACRO PROTOC_OUT_DIR PLUGIN)
+  set(_singleargs LANGUAGE OUT_VAR EXPORT_MACRO PROTOC_OUT_DIR PLUGIN PLUGIN_OPTIONS DEPENDENCIES)
   if(COMMAND target_sources)
     list(APPEND _singleargs TARGET)
   endif()
-  set(_multiargs PROTOS IMPORT_DIRS GENERATE_EXTENSIONS)
+  set(_multiargs PROTOS IMPORT_DIRS GENERATE_EXTENSIONS PROTOC_OPTIONS)
 
   cmake_parse_arguments(protobuf_generate "${_options}" "${_singleargs}" "${_multiargs}" "${ARGN}")
 
@@ -168,9 +248,18 @@ function(protobuf_generate)
   endif()
 
   if(protobuf_generate_EXPORT_MACRO AND protobuf_generate_LANGUAGE STREQUAL cpp)
-    set(_dll_export_decl "dllexport_decl=${protobuf_generate_EXPORT_MACRO}:")
+    set(_dll_export_decl "dllexport_decl=${protobuf_generate_EXPORT_MACRO}")
   endif()
 
+  foreach(_option ${_dll_export_decl} ${protobuf_generate_PLUGIN_OPTIONS})
+    # append comma - not using CMake lists and string replacement as users
+    # might have semicolons in options
+    if(_plugin_options)
+      set( _plugin_options "${_plugin_options},")
+    endif()
+    set(_plugin_options "${_plugin_options}${_option}")
+  endforeach()
+
   if(protobuf_generate_PLUGIN)
     set(_plugin "--plugin=${protobuf_generate_PLUGIN}")
   endif()
@@ -204,14 +293,12 @@ function(protobuf_generate)
     # Create an include path for each file specified
     foreach(_file ${protobuf_generate_PROTOS})
       get_filename_component(_abs_file ${_file} ABSOLUTE)
-      get_filename_component(_abs_path ${_abs_file} PATH)
-      list(FIND _protobuf_include_path ${_abs_path} _contains_already)
+      get_filename_component(_abs_dir ${_abs_file} DIRECTORY)
+      list(FIND _protobuf_include_path ${_abs_dir} _contains_already)
       if(${_contains_already} EQUAL -1)
-          list(APPEND _protobuf_include_path -I ${_abs_path})
+          list(APPEND _protobuf_include_path -I ${_abs_dir})
       endif()
     endforeach()
-  else()
-    set(_protobuf_include_path -I ${CMAKE_CURRENT_SOURCE_DIR})
   endif()
 
   foreach(DIR ${protobuf_generate_IMPORT_DIRS})
@@ -222,6 +309,10 @@ function(protobuf_generate)
     endif()
   endforeach()
 
+  if(NOT _protobuf_include_path)
+    set(_protobuf_include_path -I ${CMAKE_CURRENT_SOURCE_DIR})
+  endif()
+
   set(_generated_srcs_all)
   foreach(_proto ${protobuf_generate_PROTOS})
     get_filename_component(_abs_file ${_proto} ABSOLUTE)
@@ -246,12 +337,20 @@ function(protobuf_generate)
     endif()
     list(APPEND _generated_srcs_all ${_generated_srcs})
 
+    set(_comment "Running ${protobuf_generate_LANGUAGE} protocol buffer compiler on ${_proto}")
+    if(protobuf_generate_PROTOC_OPTIONS)
+      set(_comment "${_comment}, protoc-options: ${protobuf_generate_PROTOC_OPTIONS}")
+    endif()
+    if(_plugin_options)
+      set(_comment "${_comment}, plugin-options: ${_plugin_options}")
+    endif()
+
     add_custom_command(
       OUTPUT ${_generated_srcs}
-      COMMAND  protobuf::protoc
-      ARGS --${protobuf_generate_LANGUAGE}_out ${_dll_export_decl}${protobuf_generate_PROTOC_OUT_DIR} ${_plugin} ${_dll_desc_out} ${_protobuf_include_path} ${_abs_file}
-      DEPENDS ${_abs_file} protobuf::protoc
-      COMMENT "Running ${protobuf_generate_LANGUAGE} protocol buffer compiler on ${_proto}"
+      COMMAND protobuf::protoc
+      ARGS ${protobuf_generate_PROTOC_OPTIONS} --${protobuf_generate_LANGUAGE}_out ${_plugin_options}:${protobuf_generate_PROTOC_OUT_DIR} ${_plugin} ${_dll_desc_out} ${_protobuf_include_path} ${_abs_file}
+      DEPENDS ${_abs_file} protobuf::protoc ${protobuf_generate_DEPENDENCIES}
+      COMMENT ${_comment}
       VERBATIM )
   endforeach()