plugins: python renderer: Implement first draft that loads a python module and calls a test function. This will be changed later

command-line.c

@@ -146,6 +146,7 @@ int command_line_convert_gds(const char *gds_name,
 			      double scale)
 {
 	int ret = -1;
+	int render_ret;
 	GList *libs = NULL;
 	int res;
 	GList *renderer_list = NULL;
@@ -163,7 +164,14 @@ int command_line_convert_gds(const char *gds_name,
 
 	/* Load layer_settings */
 	layer_sett = layer_settings_new();
-	layer_settings_load_from_csv(layer_sett, layer_file);
+	if (!layer_sett)
+		goto return_value;
+
+	ret = layer_settings_load_from_csv(layer_sett, layer_file);
+	if (ret) {
+		fprintf(stderr, _("Loading layer mapping file failed.\n"));
+		goto ret_destroy_layer_mapping;
+	}
 
 	/* Create renderers */
 	if (create_renderers(renderers, output_file_names, tex_layers, tex_standalone,
@@ -221,7 +229,9 @@ int command_line_convert_gds(const char *gds_name,
 	/* Execute all rendererer instances */
 	for (list_iter = renderer_list; list_iter; list_iter = list_iter->next) {
 		current_renderer = GDS_RENDER_OUTPUT_RENDERER(list_iter->data);
-		gds_output_renderer_render_output(current_renderer, toplevel_cell, scale);
+		render_ret = gds_output_renderer_render_output(current_renderer, toplevel_cell, scale);
+		if (render_ret)
+			fprintf(stderr, "Rendering failed with error code: %d\n", render_ret);
 	}
 
 ret_destroy_library_list:
@@ -231,6 +241,7 @@ ret_clear_renderers:
 		g_object_unref(list_iter->data);
 ret_destroy_layer_mapping:
 	g_object_unref(layer_sett);
+return_value:
 	return ret;
 }
 

plugins/python-renderer/CMakeLists.txt

@@ -1,12 +1,15 @@
 project(pythonrenderer)
-cmake_minimum_required(VERSION 2.8)
-find_package(PkgConfig REQUIRED)
-pkg_search_module(PYTHON REQUIRED python3)
+cmake_minimum_required(VERSION 2.8.8)
+find_package(PythonLibs)
 
 aux_source_directory(src SOURCES)
 
 include_directories(${PYTHON_INCLUDE_DIRS} ${CMAKE_CURRENT_SOURCE_DIR}/include)
-link_libraries(${PYTHON_LDFLAGS} version)
+link_libraries(${PYTHON_LIBRARIES} version)
+
+message("Python version found: ${PYTHONLIBS_VERSION_STRING}")
+message(${PYTHON_LIBRARIES})
+message(${PYTHON_INCLUDE_DIRS})
 
 add_library(${PROJECT_NAME} SHARED EXCLUDE_FROM_ALL ${SOURCES})
 add_dependencies(${PROJECT_NAME} version)

plugins/python-renderer/src/plugin-main.c

@@ -1,26 +1,116 @@
 #include <stdio.h>
 #include <glib.h>
+#include <unistd.h>
 #include <Python.h>
 
 #include <gds-render/gds-utils/gds-types.h>
 #include <gds-render/output-renderers/external-renderer-interfaces.h>
 
+/**
+ * @brief Global variable for loaded module. This is not very nice.
+ * @warning This has to be changed, if this api wants to be re-entrant.
+ */
+static PyObject *p_module = NULL;
+
+static int check_file_exists(const char *path)
+{
+	FILE *file;
+	int ret = -1;
+
+	file = fopen(path, "rb");
+	if (file) {
+		fclose(file);
+		ret = 0;
+	}
+
+	return ret;
+}
+
 int FUNC_DECL(EXTERNAL_LIBRARY_RENDER_FUNCTION)(struct gds_cell *toplevel, GList *layer_info_list, const char *output_file_name, double scale)
 {
+	int ret = 0;
+	PyObject *p_render_func;
+	PyObject *p_return_value;
+
 	if (!toplevel)
 		return -1000;
+	if (!p_module)
+		return -2000;
 
 	printf("Rendering %s\n", toplevel->name);
-	return 0;
+
+	p_render_func = PyObject_GetAttrString(p_module, "test_func");
+	if (!p_render_func && !PyCallable_Check(p_render_func)) {
+		if (PyErr_Occurred())
+			PyErr_Print();
+		else
+			fprintf(stderr, "function not found in python module\n");
+
+		ret = -1;
+		goto return_value;
+	}
+
+	p_return_value = PyObject_CallObject(p_render_func, NULL);
+	if (p_return_value) {
+		printf("Result of call: %ld\n", PyLong_AsLong(p_return_value));
+		Py_DECREF(p_return_value);
+	}
+
+return_value:
+	return ret;
 }
 
 int FUNC_DECL(EXTERNAL_LIBRARY_INIT_FUNCTION)(const char *params, const char *version)
 {
-	PyObject *p_module_name;
+	int ret = 0;
+	PyObject *p_name;
+	PyObject *p_sys_path;
+	PyObject *p_cwd_string;
+	char cwd[256];
+
+	if (!params || !version)
+		return -1000;
 
 	printf("Init with params: %s\ngds-render version: %s\n", params, version);
-
 	Py_Initialize();
 
-	return 0;
+	if (!getcwd(cwd, sizeof(cwd))) {
+		return -2;
+	}
+
+	p_sys_path = PySys_GetObject("path");
+	p_cwd_string = PyUnicode_FromString(cwd);
+	PyList_Append(p_sys_path, p_cwd_string);
+	Py_DECREF(p_cwd_string);
+
+	/* This renderer has only one parameter: The name of the file */
+	/*if (check_file_exists(params))
+		return -1001;
+	*/
+
+	p_name = PyUnicode_DecodeFSDefault(params);
+	p_module = PyImport_Import(p_name);
+	Py_DECREF(p_name);
+
+	if (!p_module) {
+		PyErr_Print();
+		fprintf(stderr, "Failed to load %s\n", params);
+		ret = -1;
+		goto return_value;
+	}
+
+return_value:
+	return ret;
+}
+
+int FUNC_DECL(EXTERNAL_LIBRARY_FINALIZE_FUNCTION)(void)
+{
+	int ret;
+
+	printf("Finalizing\n");
+
+	if (p_module)
+		Py_DECREF(p_module);
+	ret = Py_FinalizeEx();
+	return ret;
 }