/* $Id$ * $URL$ * * Python plugin * * Copyright 2005 Dan Fritz * Copyright 2005 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net> * * This file is part of LCD4Linux. * * LCD4Linux is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * LCD4Linux is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * */ /* * exported functions: * * int plugin_init_python (void) * adds a python interpreter * */ #include <Python.h> #include "debug.h" #include "plugin.h" /* * Executes a python function specified by function name and module. * * This method is more or less a copy of an example found in the python * documentation. Kudos goes to Guido van Rossum and Fred L. Drake. * * Fixme: this function should be able to accept and receive any types * of arguments supported by the evaluator. Right now only strings are accepted. */ static void pyt_exec_str(RESULT * result, const char *module, const char *function, int argc, const char *argv[]) { PyObject *pName, *pModule, *pDict, *pFunc; PyObject *pArgs, *pValue; const char *rv = NULL; int i; pName = PyString_FromString(module); /* Error checking of pName left out */ pModule = PyImport_Import(pName); Py_DECREF(pName); if (pModule != NULL) { pDict = PyModule_GetDict(pModule); /* pDict is a borrowed reference */ pFunc = PyDict_GetItemString(pDict, function); /* pFun: Borrowed reference */ if (pFunc && PyCallable_Check(pFunc)) { pArgs = PyTuple_New(argc); for (i = 0; i < argc; ++i) { pValue = PyString_FromString(argv[i]); if (!pValue) { Py_DECREF(pArgs); Py_DECREF(pModule); error("Cannot convert argument \"%s\" to python format", argv[i]); SetResult(&result, R_STRING, ""); return; } /* pValue reference stolen here: */ PyTuple_SetItem(pArgs, i, pValue); } pValue = PyObject_CallObject(pFunc, pArgs); Py_DECREF(pArgs); if (pValue != NULL) { rv = PyString_AsString(pValue); SetResult(&result, R_STRING, rv); Py_DECREF(pValue); /* rv is now a 'dangling reference' */ return; } else { Py_DECREF(pModule); error("Python call failed (\"%s.%s\")", module, function); SetResult(&result, R_STRING, ""); return; } /* pDict and pFunc are borrowed and must not be Py_DECREF-ed */ } else { error("Can not find python function \"%s.%s\"", module, function); } Py_DECREF(pModule); } else { error("Failed to load python module \"%s\"", module); } SetResult(&result, R_STRING, ""); return; } static int python_cleanup_responsibility = 0; static void my_exec(RESULT * result, RESULT * module, RESULT * function, RESULT * arg) { /* Fixme: a plugin should be able to accept any number of arguments, don't know how to code that (yet) */ const char *args[] = { R2S(arg) }; pyt_exec_str(result, R2S(module), R2S(function), 1, args); } int plugin_init_python(void) { if (!Py_IsInitialized()) { Py_Initialize(); python_cleanup_responsibility = 1; } AddFunction("python::exec", 3, my_exec); return 0; } void plugin_exit_python(void) { /* Make sure NOT to call Py_Finalize() When (and if) the entire lcd4linux process * is started from inside python */ if (python_cleanup_responsibility) { python_cleanup_responsibility = 0; Py_Finalize(); } }