Set Python program name during init

Author: jonatanklosko

.github/workflows/test.yml

@@ -5,6 +5,7 @@ on:
     branches:
       - main
       - "v*.*"
+      - jk-init
 jobs:
   linux:
     runs-on: ubuntu-20.04

c_src/pythonx/python.cpp

@@ -77,6 +77,7 @@ DEF_SYMBOL(Py_IsFalse)
 DEF_SYMBOL(Py_IsNone)
 DEF_SYMBOL(Py_IsTrue)
 DEF_SYMBOL(Py_SetPythonHome)
+DEF_SYMBOL(Py_SetProgramName)
 
 dl::LibraryHandle python_library;
 
@@ -150,6 +151,7 @@ void load_python_library(std::string path) {
   LOAD_SYMBOL(python_library, Py_IsNone)
   LOAD_SYMBOL(python_library, Py_IsTrue)
   LOAD_SYMBOL(python_library, Py_SetPythonHome)
+  LOAD_SYMBOL(python_library, Py_SetProgramName)
 }
 
 void unload_python_library() {

c_src/pythonx/python.hpp

@@ -131,6 +131,7 @@ extern int (*Py_IsFalse)(PyObjectPtr);
 extern int (*Py_IsNone)(PyObjectPtr);
 extern int (*Py_IsTrue)(PyObjectPtr);
 extern void (*Py_SetPythonHome)(const wchar_t *);
+extern void (*Py_SetProgramName)(const wchar_t *);
 
 // Opens Python dynamic library at the given path and looks up all
 // relevant symbols.

c_src/pythonx/pythonx.cpp

@@ -23,6 +23,7 @@ using namespace python;
 std::mutex init_mutex;
 bool is_initialized = false;
 std::wstring python_home_path_w;
+std::wstring python_executable_path_w;
 std::map<std::string, std::tuple<PyObjectPtr, PyObjectPtr>> compilation_cache;
 std::mutex compilation_cache_mutex;
 
@@ -225,6 +226,7 @@ ERL_NIF_TERM py_object_to_binary_term(ErlNifEnv *env, PyObjectPtr py_object) {
 
 fine::Ok<> init(ErlNifEnv *env, std::string python_dl_path,
                 ErlNifBinary python_home_path,
+                ErlNifBinary python_executable_path,
                 std::vector<ErlNifBinary> sys_paths) {
   auto init_guard = std::lock_guard<std::mutex>(init_mutex);
 
@@ -240,6 +242,10 @@ fine::Ok<> init(ErlNifEnv *env, std::string python_dl_path,
   python_home_path_w = std::wstring(
       python_home_path.data, python_home_path.data + python_home_path.size);
 
+  python_executable_path_w =
+      std::wstring(python_executable_path.data,
+                   python_executable_path.data + python_executable_path.size);
+
   // As part of the initialization, sys.path is set. It is important
   // that it gets set correctly, so that the built-in modules can be
   // found, otherwise the initialization fails. This logic is internal
@@ -259,6 +265,8 @@ fine::Ok<> init(ErlNifEnv *env, std::string python_dl_path,
   // [1]: https://docs.python.org/3/using/cmdline.html#envvar-PYTHONHOME
   Py_SetPythonHome(python_home_path_w.c_str());
 
+  Py_SetProgramName(python_executable_path_w.c_str());
+
   Py_InitializeEx(0);
 
   // In order to use any of the Python C API functions, the calling

lib/pythonx.ex

@@ -38,7 +38,7 @@ defmodule Pythonx do
 
   """
   @spec init(String.t(), String.t(), keyword()) :: :ok
-  def init(python_dl_path, python_home_path, opts \\ [])
+  def init(python_dl_path, python_home_path, python_executable_path, opts \\ [])
       when is_binary(python_dl_path) and is_binary(python_home_path) and is_list(opts) do
     opts = Keyword.validate!(opts, sys_paths: [])
 
@@ -50,7 +50,7 @@ defmodule Pythonx do
       raise ArgumentError, "the given python home directory does not exist: #{python_home_path}"
     end
 
-    Pythonx.NIF.init(python_dl_path, python_home_path, opts[:sys_paths])
+    Pythonx.NIF.init(python_dl_path, python_home_path, python_executable_path, opts[:sys_paths])
   end
 
   @doc ~S'''

lib/pythonx/nif.ex

@@ -12,7 +12,7 @@ defmodule Pythonx.NIF do
     end
   end
 
-  def init(_python_dl_path, _python_home_path, _sys_paths), do: err!()
+  def init(_python_dl_path, _python_home_path, _python_executable_path, _sys_paths), do: err!()
   def terminate(), do: err!()
   def janitor_decref(_ptr), do: err!()
   def none_new(), do: err!()

lib/pythonx/uv.ex

@@ -106,12 +106,16 @@ defmodule Pythonx.Uv do
 
         python_home_path = make_windows_slashes(root_dir)
 
+        python_executable_path = Path.join(abs_executable_dir, "python.exe")
+
         venv_packages_path =
           project_dir
           |> Path.join(".venv/Lib/site-packages")
           |> make_windows_slashes()
 
-        Pythonx.init(python_dl_path, python_home_path, sys_paths: [venv_packages_path])
+        Pythonx.init(python_dl_path, python_home_path, python_executable_path,
+          sys_paths: [venv_packages_path]
+        )
 
       {:unix, osname} ->
         dl_extension =
@@ -128,12 +132,16 @@ defmodule Pythonx.Uv do
 
         python_home_path = root_dir
 
+        python_executable_path = Path.join(abs_executable_dir, "python")
+
         venv_packages_path =
           project_dir
           |> Path.join(".venv/lib/python3*/site-packages")
           |> wildcard_one!()
 
-        Pythonx.init(python_dl_path, python_home_path, sys_paths: [venv_packages_path])
+        Pythonx.init(python_dl_path, python_home_path, python_executable_path,
+          sys_paths: [venv_packages_path]
+        )
     end
   end