gh-105145: Remove old functions to config Python init (#105154)

Remove the following old functions to configure the Python
initialization, deprecated in Python 3.11:

* PySys_AddWarnOptionUnicode()
* PySys_AddWarnOption()
* PySys_AddXOption()
* PySys_HasWarnOptions()
* PySys_SetArgvEx()
* PySys_SetArgv()
* PySys_SetPath()
* Py_SetPath()
* Py_SetProgramName()
* Py_SetPythonHome()
* Py_SetStandardStreamEncoding()
* _Py_SetProgramFullPath()

Most of these functions are kept in the stable ABI, except:

* Py_SetStandardStreamEncoding()
* _Py_SetProgramFullPath()

Update Doc/extending/embedding.rst and Doc/extending/extending.rst to
use the new PyConfig API.

_testembed.c:

* check_stdio_details() now sets stdio_encoding and stdio_errors
  of PyConfig.
* Add definitions of functions removed from the API but kept in the
  stable ABI.
* test_init_from_config() and test_init_read_set() now use
  PyConfig_SetString() instead of PyConfig_SetBytesString().

Remove _Py_ClearStandardStreamEncoding() internal function.

4 files changed, 20 insertions, 141 deletions

diff --git a/Python/initconfig.c b/Python/initconfig.c
index 0d42b7e..1dcefd4 100644
--- a/Python/initconfig.c
+++ b/Python/initconfig.c
@@ -514,94 +514,6 @@ _PyWideStringList_AsList(const PyWideStringList *list)
 }
 
 
-/* --- Py_SetStandardStreamEncoding() ----------------------------- */
-
-/* Helper to allow an embedding application to override the normal
- * mechanism that attempts to figure out an appropriate IO encoding
- */
-
-static char *_Py_StandardStreamEncoding = NULL;
-static char *_Py_StandardStreamErrors = NULL;
-
-int
-Py_SetStandardStreamEncoding(const char *encoding, const char *errors)
-{
-    if (Py_IsInitialized()) {
-        /* This is too late to have any effect */
-        return -1;
-    }
-
-    int res = 0;
-
-    /* Py_SetStandardStreamEncoding() can be called before Py_Initialize(),
-       but Py_Initialize() can change the allocator. Use a known allocator
-       to be able to release the memory later. */
-    PyMemAllocatorEx old_alloc;
-    _PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
-
-    /* Can't call PyErr_NoMemory() on errors, as Python hasn't been
-     * initialised yet.
-     *
-     * However, the raw memory allocators are initialised appropriately
-     * as C static variables, so _PyMem_RawStrdup is OK even though
-     * Py_Initialize hasn't been called yet.
-     */
-    if (encoding) {
-        PyMem_RawFree(_Py_StandardStreamEncoding);
-        _Py_StandardStreamEncoding = _PyMem_RawStrdup(encoding);
-        if (!_Py_StandardStreamEncoding) {
-            res = -2;
-            goto done;
-        }
-    }
-    if (errors) {
-        PyMem_RawFree(_Py_StandardStreamErrors);
-        _Py_StandardStreamErrors = _PyMem_RawStrdup(errors);
-        if (!_Py_StandardStreamErrors) {
-            PyMem_RawFree(_Py_StandardStreamEncoding);
-            _Py_StandardStreamEncoding = NULL;
-            res = -3;
-            goto done;
-        }
-    }
-#ifdef MS_WINDOWS
-    if (_Py_StandardStreamEncoding) {
-_Py_COMP_DIAG_PUSH
-_Py_COMP_DIAG_IGNORE_DEPR_DECLS
-        /* Overriding the stream encoding implies legacy streams */
-        Py_LegacyWindowsStdioFlag = 1;
-_Py_COMP_DIAG_POP
-    }
-#endif
-
-done:
-    PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
-
-    return res;
-}
-
-
-void
-_Py_ClearStandardStreamEncoding(void)
-{
-    /* Use the same allocator than Py_SetStandardStreamEncoding() */
-    PyMemAllocatorEx old_alloc;
-    _PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
-
-    /* We won't need them anymore. */
-    if (_Py_StandardStreamEncoding) {
-        PyMem_RawFree(_Py_StandardStreamEncoding);
-        _Py_StandardStreamEncoding = NULL;
-    }
-    if (_Py_StandardStreamErrors) {
-        PyMem_RawFree(_Py_StandardStreamErrors);
-        _Py_StandardStreamErrors = NULL;
-    }
-
-    PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
-}
-
-
 /* --- Py_GetArgcArgv() ------------------------------------------- */
 
 void
@@ -1973,26 +1885,6 @@ config_init_stdio_encoding(PyConfig *config,
 {
     PyStatus status;
 
-    /* If Py_SetStandardStreamEncoding() has been called, use its
-        arguments if they are not NULL. */
-    if (config->stdio_encoding == NULL && _Py_StandardStreamEncoding != NULL) {
-        status = CONFIG_SET_BYTES_STR(config, &config->stdio_encoding,
-                                      _Py_StandardStreamEncoding,
-                                      "_Py_StandardStreamEncoding");
-        if (_PyStatus_EXCEPTION(status)) {
-            return status;
-        }
-    }
-
-    if (config->stdio_errors == NULL && _Py_StandardStreamErrors != NULL) {
-        status = CONFIG_SET_BYTES_STR(config, &config->stdio_errors,
-                                      _Py_StandardStreamErrors,
-                                      "_Py_StandardStreamErrors");
-        if (_PyStatus_EXCEPTION(status)) {
-            return status;
-        }
-    }
-
     // Exit if encoding and errors are defined
     if (config->stdio_encoding != NULL && config->stdio_errors != NULL) {
         return _PyStatus_OK();
diff --git a/Python/pathconfig.c b/Python/pathconfig.c
index be0f97c..afffa13 100644
--- a/Python/pathconfig.c
+++ b/Python/pathconfig.c
@@ -211,7 +211,8 @@ path_out_of_memory(const char *func)
     _Py_FatalErrorFunc(func, "out of memory");
 }
 
-void
+// Removed in Python 3.13 API, but kept for the stable ABI
+PyAPI_FUNC(void)
 Py_SetPath(const wchar_t *path)
 {
     if (path == NULL) {
@@ -252,7 +253,8 @@ Py_SetPath(const wchar_t *path)
 }
 
 
-void
+// Removed in Python 3.13 API, but kept for the stable ABI
+PyAPI_FUNC(void)
 Py_SetPythonHome(const wchar_t *home)
 {
     int has_value = home && home[0];
@@ -275,7 +277,8 @@ Py_SetPythonHome(const wchar_t *home)
 }
 
 
-void
+// Removed in Python 3.13 API, but kept for the stable ABI
+PyAPI_FUNC(void)
 Py_SetProgramName(const wchar_t *program_name)
 {
     int has_value = program_name && program_name[0];
@@ -297,28 +300,6 @@ Py_SetProgramName(const wchar_t *program_name)
     }
 }
 
-void
-_Py_SetProgramFullPath(const wchar_t *program_full_path)
-{
-    int has_value = program_full_path && program_full_path[0];
-
-    PyMemAllocatorEx old_alloc;
-    _PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
-
-    PyMem_RawFree(_Py_path_config.program_full_path);
-    _Py_path_config.program_full_path = NULL;
-
-    if (has_value) {
-        _Py_path_config.program_full_path = _PyMem_RawWcsdup(program_full_path);
-    }
-
-    PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
-
-    if (has_value && _Py_path_config.program_full_path == NULL) {
-        path_out_of_memory(__func__);
-    }
-}
-
 
 wchar_t *
 Py_GetPath(void)
diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index 06c4345..c6fbf17 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -2556,7 +2556,6 @@ error:
     res = _PyStatus_ERR("can't initialize sys standard streams");
 
 done:
-    _Py_ClearStandardStreamEncoding();
     Py_XDECREF(iomod);
     return res;
 }
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index 32be7ec..4427e73 100644
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -2614,7 +2614,8 @@ _PySys_AddWarnOptionWithError(PyThreadState *tstate, PyObject *option)
     return 0;
 }
 
-void
+// Removed in Python 3.13 API, but kept for the stable ABI
+PyAPI_FUNC(void)
 PySys_AddWarnOptionUnicode(PyObject *option)
 {
     PyThreadState *tstate = _PyThreadState_GET();
@@ -2626,7 +2627,8 @@ PySys_AddWarnOptionUnicode(PyObject *option)
     }
 }
 
-void
+// Removed in Python 3.13 API, but kept for the stable ABI
+PyAPI_FUNC(void)
 PySys_AddWarnOption(const wchar_t *s)
 {
     PyThreadState *tstate = _PyThreadState_GET();
@@ -2645,7 +2647,8 @@ _Py_COMP_DIAG_POP
     Py_DECREF(unicode);
 }
 
-int
+// Removed in Python 3.13 API, but kept for the stable ABI
+PyAPI_FUNC(int)
 PySys_HasWarnOptions(void)
 {
     PyThreadState *tstate = _PyThreadState_GET();
@@ -2718,7 +2721,8 @@ error:
     return -1;
 }
 
-void
+// Removed in Python 3.13 API, but kept for the stable ABI
+PyAPI_FUNC(void)
 PySys_AddXOption(const wchar_t *s)
 {
     PyThreadState *tstate = _PyThreadState_GET();
@@ -3621,7 +3625,8 @@ makepathobject(const wchar_t *path, wchar_t delim)
     return v;
 }
 
-void
+// Removed in Python 3.13 API, but kept for the stable ABI
+PyAPI_FUNC(void)
 PySys_SetPath(const wchar_t *path)
 {
     PyObject *v;
@@ -3653,7 +3658,8 @@ make_sys_argv(int argc, wchar_t * const * argv)
     return list;
 }
 
-void
+// Removed in Python 3.13 API, but kept for the stable ABI
+PyAPI_FUNC(void)
 PySys_SetArgvEx(int argc, wchar_t **argv, int updatepath)
 {
     wchar_t* empty_argv[1] = {L""};
@@ -3697,7 +3703,8 @@ PySys_SetArgvEx(int argc, wchar_t **argv, int updatepath)
     }
 }
 
-void
+// Removed in Python 3.13 API, but kept for the stable ABI
+PyAPI_FUNC(void)
 PySys_SetArgv(int argc, wchar_t **argv)
 {
 _Py_COMP_DIAG_PUSH