bpo-29240: Fix locale encodings in UTF-8 Mode (#5170)

Modify locale.localeconv(), time.tzname, os.strerror() and other
functions to ignore the UTF-8 Mode: always use the current locale
encoding.

Changes:

* Add _Py_DecodeLocaleEx() and _Py_EncodeLocaleEx(). On decoding or
  encoding error, they return the position of the error and an error
  message which are used to raise Unicode errors in
  PyUnicode_DecodeLocale() and PyUnicode_EncodeLocale().
* Replace _Py_DecodeCurrentLocale() with _Py_DecodeLocaleEx().
* PyUnicode_DecodeLocale() now uses _Py_DecodeLocaleEx() for all
  cases, especially for the strict error handler.
* Add _Py_DecodeUTF8Ex(): return more information on decoding error
  and supports the strict error handler.
* Rename _Py_EncodeUTF8_surrogateescape() to _Py_EncodeUTF8Ex().
* Replace _Py_EncodeCurrentLocale() with _Py_EncodeLocaleEx().
* Ignore the UTF-8 mode to encode/decode localeconv(), strerror()
  and time zone name.
* Remove PyUnicode_DecodeLocale(), PyUnicode_DecodeLocaleAndSize()
  and PyUnicode_EncodeLocale() now ignore the UTF-8 mode: always use
  the "current" locale.
* Remove _PyUnicode_DecodeCurrentLocale(),
  _PyUnicode_DecodeCurrentLocaleAndSize() and
  _PyUnicode_EncodeCurrentLocale().

1 files changed, 2 insertions, 2 deletions

diff --git a/Python/pathconfig.c b/Python/pathconfig.c
index 9591fcc..7ebd69b 100644
--- a/Python/pathconfig.c
+++ b/Python/pathconfig.c
@@ -382,8 +382,8 @@ _Py_FindEnvConfigValue(FILE *env_file, const wchar_t *key,
             /* Comment - skip */
             continue;
         }
-        tmpbuffer = _Py_DecodeUTF8_surrogateescape(buffer, n, NULL);
-        if (tmpbuffer != NULL) {
+        tmpbuffer = _Py_DecodeUTF8_surrogateescape(buffer, n);
+        if (tmpbuffer) {
             wchar_t * state;
             wchar_t * tok = wcstok(tmpbuffer, L" \t\r\n", &state);
             if ((tok != NULL) && !wcscmp(tok, key)) {