#3907: add component info in conanfile.py, add cmake helper module, e…

recipes/flatcc/all/FlatccGenerateSources.cmake

@@ -0,0 +1,88 @@
+
+# Use the following function to generate C source files from flatbuffer definition files:
+#
+# flatcc_generate_sources(GENERATED_SOURCE_DIRECTORY <directory where to write source files>
+#                         GENERATE_BUILDER
+#                         GENERATE_VERIFIER
+#                         EXPECTED_OUTPUT_FILES <list of files that flatcc is supposed to generate>
+#                         DEFINITION_FILES <list of flatbuffer definition files (.fbs)>
+# )
+#
+# GENERATE_BUILDER and GENERATE_VERIFIER are boolean options. When specified they will instruct
+# flatcc to generate builder / verifier source code.
+#
+# With cross-compiling you should provide the directory where the flatcc compiler executable is located
+# in environment variable FLATCC_BUILD_BIN_PATH. If you use Conan and add flatcc as a build requirement
+# this will be done automatically.
+
+
+function(flatcc_generate_sources)
+
+    # parse function arguments
+    set(OUTPREFIX "FLATCC") #variables created by 'cmake_parse_arguments' will be prefixed with this
+    set(NO_VAL_ARGS GENERATE_BUILDER GENERATE_VERIFIER)
+    set(SINGLE_VAL_ARGS GENERATED_SOURCE_DIRECTORY)
+    set(MULTI_VAL_ARGS DEFINITION_FILES EXPECTED_OUTPUT_FILES CC_OPTIONS)
+
+    cmake_parse_arguments(${OUTPREFIX}
+                          "${NO_VAL_ARGS}"
+                          "${SINGLE_VAL_ARGS}"
+                          "${MULTI_VAL_ARGS}"
+                          ${ARGN}
+    )
+    if (GENERATED_SOURCE_DIRECTORY IN_LIST FLATCC_KEYWORDS_MISSING_VALUES)
+        message(FATAL_ERROR "No directory provided after GENERATED_SOURCE_DIRECTORY keyword")
+    endif()
+    if (NOT FLATCC_GENERATED_SOURCE_DIRECTORY)
+        set(FLATCC_GENERATED_SOURCE_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+    endif()
+    message(STATUS "Flatcc sources will be generated in directory ${FLATCC_GENERATED_SOURCE_DIRECTORY}")
+
+    if (FLATCC_GENERATE_BUILDER)
+        list(APPEND FLATCC_CC_OPTIONS --builder)
+    endif()
+    if (FLATCC_GENERATE_VERIFIER)
+        list(APPEND FLATCC_CC_OPTIONS --verifier)
+    endif()
+
+    if (FLATCC_DEFINITION_FILES)
+        if (NOT EXISTS ${FLATCC_GENERATED_SOURCE_DIRECTORY})
+            file(MAKE_DIRECTORY ${FLATCC_GENERATED_SOURCE_DIRECTORY})
+        endif()
+
+        message(VERBOSE "Executing command ${FLATCC_COMPILER} ${FLATCC_CC_OPTIONS} -o ${FLATCC_GENERATED_SOURCE_DIRECTORY} ${FLATCC_DEFINITION_FILES}")
+        add_custom_command(OUTPUT ${FLATCC_EXPECTED_OUTPUT_FILES}
+                           COMMAND ${FLATCC_COMPILER} ${FLATCC_CC_OPTIONS} -o ${FLATCC_GENERATED_SOURCE_DIRECTORY} ${FLATCC_DEFINITION_FILES}
+                           WORKING_DIRECTORY ${FLATCC_GENERATED_SOURCE_DIRECTORY})
+    else()
+        message(WARNING "No flatbuffer definition files provided, no sources will be generated")
+    endif()
+
+endfunction()
+
+
+#### Main ####
+
+#When cross-compiling user can provide location of the flatbuffers to C compiler in build arch via
+#environment variable FLATCC_BUILD_BIN_PATH
+set(FLATCC_BIN_PATH "$ENV{FLATCC_BUILD_BIN_PATH}")
+if (FLATCC_BIN_PATH)
+    #user provided location where asn1c compiler executable is installed
+    find_program(FLATCC_COMPILER flatcc
+                 PATHS ${FLATCC_BIN_PATH}
+                 NO_DEFAULT_PATH
+                 NO_SYSTEM_ENVIRONMENT_PATH
+                 NO_CMAKE_SYSTEM_PATH
+)
+else()
+    #Find compiler exe in current install location
+    find_program(FLATCC_COMPILER flatcc
+                NO_SYSTEM_ENVIRONMENT_PATH
+                NO_CMAKE_SYSTEM_PATH
+    )
+endif()
+
+
+if (NOT FLATCC_COMPILER)
+    message(FATAL_ERROR "Could not locate the flatcc compiler executable")
+endif()

recipes/flatcc/all/conanfile.py

@@ -35,7 +35,7 @@ class FlatccConan(ConanFile):
     }
     settings = "os", "arch", "compiler", "build_type"
     generators = "cmake"
-    exports_sources = ["CMakeLists.txt"]
+    exports_sources = ["CMakeLists.txt", "FlatccGenerateSources.cmake"]
 
     _cmake = None
 
@@ -89,7 +89,6 @@ def build(self):
         cmake = self._configure_cmake()
         cmake.build()
 
-
     def package(self):
         cmake = self._configure_cmake()
         cmake.install()
@@ -99,12 +98,24 @@ def package(self):
                       os.path.join(self.package_folder, "bin", "flatcc"))
         # Copy license file
         self.copy("LICENSE", dst="licenses", src=self._source_subfolder)
+        # Copy file with cmake functions for end user
+        self.copy("FlatccGenerateSources.cmake", dst="cmake")
 
     def package_info(self):
-        bin_path = os.path.join(self.package_folder, "bin")
-        self.output.info('Appending PATH environment variable: %s' % bin_path)
-        self.env_info.PATH.append(bin_path)
         debug_suffix = "_d" if self.settings.build_type == "Debug" else ""
+        #flatcc package provides two components: the flatcc compiler binary and the runtime library
         if not self.options.runtime_lib_only:
-            self.cpp_info.libs.append("flatcc%s" % debug_suffix)
-        self.cpp_info.libs.append("flatccrt%s" % debug_suffix)
+            self.cpp_info.components["flatcc_exe"].names["cmake_find_package"] = "flatcc_exe"
+            self.cpp_info.components["flatcc_exe"].libs = ["flatcc%s" % debug_suffix]
+            #Our FlatccGenerateSources.cmake should be included by the cmake_find_package generated file
+            self.cpp_info.components["flatcc_exe"].build_modules.append(os.path.join(self.package_folder, "cmake", "FlatccGenerateSources.cmake"))
+            bin_path = os.path.join(self.package_folder, "bin")
+            self.env_info.PATH.append(bin_path)
+            #When we are cross-compiling cmake needs to know the location of the flatbuffer compiler executable
+            #compiled for the build architecture. Provide it via environment variable.
+            settings_target = getattr(self, 'settings_target', None)
+            if settings_target != None:
+                self.env_info.FLATCC_BUILD_BIN_PATH = os.path.join(self.package_folder, "bin")
+        self.cpp_info.components["flatcc_rt"].names["cmake_find_package"] = "flatcc_rt"
+        self.cpp_info.components["flatcc_rt"].libs = ["flatccrt%s" % debug_suffix]
+        self.cpp_info.components["flatcc_rt"].includedirs.append(os.path.join("include", "flatcc", "reflection"))