Merge pull request #515 from YosysHQ/python_improvements

Python code cleanup

common/command.cc

@@ -321,7 +321,7 @@ int CommandHandler::executeMain(std::unique_ptr<Context> ctx)
     }
 
 #ifndef NO_PYTHON
-    init_python(argv[0], true);
+    init_python(argv[0]);
     python_export_global("ctx", *ctx);
 
     if (vm.count("run")) {

common/pybindings.cc

@@ -26,7 +26,6 @@
 #include "log.h"
 #include "nextpnr.h"
 
-#include <boost/filesystem.hpp>
 #include <fstream>
 #include <memory>
 #include <signal.h>
@@ -84,7 +83,7 @@ template <> struct string_converter<Property>
 
 } // namespace PythonConversion
 
-PYBIND11_MODULE(MODULE_NAME, m)
+PYBIND11_EMBEDDED_MODULE(MODULE_NAME, m)
 {
     py::register_exception_translator([](std::exception_ptr p) {
         try {
@@ -272,7 +271,7 @@ PYBIND11_MODULE(MODULE_NAME, m)
 static wchar_t *program;
 #endif
 
-void init_python(const char *executable, bool first)
+void init_python(const char *executable)
 {
 #ifdef MAIN_EXECUTABLE
     program = Py_DecodeLocale(executable, NULL);
@@ -280,24 +279,10 @@ void init_python(const char *executable, bool first)
         fprintf(stderr, "Fatal error: cannot decode executable filename\n");
         exit(1);
     }
-    try {
-        if (first)
-            PyImport_AppendInittab(TOSTRING(MODULE_NAME), PYINIT_MODULE_NAME);
-        Py_SetProgramName(program);
-        Py_Initialize();
-
-        // Add cwd to Python's search path so `import` can be used in user scripts
-        boost::filesystem::path cwd = boost::filesystem::absolute("./").normalize();
-        PyObject *sys_path = PySys_GetObject("path");
-        PyList_Insert(sys_path, 0, PyUnicode_FromString(cwd.string().c_str()));
-
-        PyImport_ImportModule(TOSTRING(MODULE_NAME));
-        PyRun_SimpleString("from " TOSTRING(MODULE_NAME) " import *");
-    } catch (py::error_already_set const &) {
-        // Parse and output the exception
-        std::string perror_str = parse_python_exception();
-        std::cout << "Error in Python: " << perror_str << std::endl;
-    }
+    Py_SetProgramName(program);
+    py::initialize_interpreter();
+    py::module::import(TOSTRING(MODULE_NAME));
+    PyRun_SimpleString("from " TOSTRING(MODULE_NAME) " import *");
     signal(SIGINT, SIG_DFL);
 #endif
 }
@@ -305,7 +290,7 @@ void init_python(const char *executable, bool first)
 void deinit_python()
 {
 #ifdef MAIN_EXECUTABLE
-    Py_Finalize();
+    py::finalize_interpreter();
     PyMem_RawFree(program);
 #endif
 }

common/pybindings.h

@@ -24,6 +24,7 @@
 #include <Python.h>
 #include <iostream>
 #include <pybind11/pybind11.h>
+#include <pybind11/embed.h>
 #include <stdexcept>
 #include <utility>
 #include "pycontainers.h"
@@ -35,19 +36,15 @@ NEXTPNR_NAMESPACE_BEGIN
 
 namespace py = pybind11;
 
+
 std::string parse_python_exception();
 
 template <typename Tn> void python_export_global(const char *name, Tn &x)
 {
-    PyObject *m, *d;
-    m = PyImport_AddModule("__main__");
-    if (m == NULL)
-        return;
-    d = PyModule_GetDict(m);
     try {
         py::object obj = py::cast(x, py::return_value_policy::reference);
-        PyDict_SetItemString(d, name, obj.ptr());
-    } catch (py::error_already_set const &) {
+        py::module::import("__main__").attr(name) = obj.ptr();
+    } catch (pybind11::error_already_set  &) {
         // Parse and output the exception
         std::string perror_str = parse_python_exception();
         std::cout << "Error in Python: " << perror_str << std::endl;
@@ -55,7 +52,7 @@ template <typename Tn> void python_export_global(const char *name, Tn &x)
     }
 };
 
-void init_python(const char *executable, bool first);
+void init_python(const char *executable);
 
 void deinit_python();
 

gui/pythontab.cc

@@ -96,10 +96,9 @@ void PythonTab::newContext(Context *ctx)
     console->clear();
 
     pyinterpreter_preinit();
-    init_python("nextpnr", true);
+    init_python("nextpnr");
     pyinterpreter_initialize();
     pyinterpreter_aquire();
-    init_python("nextpnr", false);
     python_export_global("ctx", ctx);
     pyinterpreter_release();