bpo-29240, bpo-32030: Py_Main() re-reads config if encoding changes (#4899)

bpo-29240, bpo-32030: If the encoding change (C locale coerced or
UTF-8 Mode changed), Py_Main() now reads again the configuration with
the new encoding.

Changes:

* Add _Py_UnixMain() called by main().
* Rename pymain_free_pymain() to pymain_clear_pymain(), it can now be
  called multipled times.
* Rename pymain_parse_cmdline_envvars() to pymain_read_conf().
* Py_Main() now clears orig_argc and orig_argv at exit.
* Remove argv_copy2, Py_Main() doesn't modify argv anymore. There is
  no need anymore to get two copies of the wchar_t** argv.
* _PyCoreConfig: add coerce_c_locale and coerce_c_locale_warn.
* Py_UTF8Mode is now initialized to -1.
* Locale coercion (PEP 538) now respects -I and -E options.

1 files changed, 2 insertions, 2 deletions

diff --git a/Python/fileutils.c b/Python/fileutils.c
index 4b69049ce5..c4d495d0d6 100644
--- a/Python/fileutils.c
+++ b/Python/fileutils.c
@@ -393,7 +393,7 @@ Py_DecodeLocale(const char* arg, size_t *size)
 #if defined(__APPLE__) || defined(__ANDROID__)
     return _Py_DecodeUTF8_surrogateescape(arg, strlen(arg), size);
 #else
-    if (Py_UTF8Mode) {
+    if (Py_UTF8Mode == 1) {
         return _Py_DecodeUTF8_surrogateescape(arg, strlen(arg), size);
     }
 
@@ -539,7 +539,7 @@ Py_EncodeLocale(const wchar_t *text, size_t *error_pos)
 #if defined(__APPLE__) || defined(__ANDROID__)
     return _Py_EncodeLocaleUTF8(text, error_pos);
 #else   /* __APPLE__ */
-    if (Py_UTF8Mode) {
+    if (Py_UTF8Mode == 1) {
         return _Py_EncodeLocaleUTF8(text, error_pos);
     }