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, 1 insertions, 90 deletions

diff --git a/Programs/python.c b/Programs/python.c
index aef7122..a295486 100644
--- a/Programs/python.c
+++ b/Programs/python.c
@@ -17,98 +17,9 @@ wmain(int argc, wchar_t **argv)
 #else
 
 
-static void _Py_NO_RETURN
-fatal_error(const char *msg)
-{
-    fprintf(stderr, "Fatal Python error: %s\n", msg);
-    fflush(stderr);
-    exit(1);
-}
-
-
 int
 main(int argc, char **argv)
 {
-    wchar_t **argv_copy;
-    /* We need a second copy, as Python might modify the first one. */
-    wchar_t **argv_copy2;
-    int i, status;
-    char *oldloc;
-
-    _PyInitError err = _PyRuntime_Initialize();
-    if (_Py_INIT_FAILED(err)) {
-        fatal_error(err.msg);
-    }
-
-    /* Force default allocator, to be able to release memory above
-       with a known allocator. */
-    _PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, NULL);
-
-    argv_copy = (wchar_t **)PyMem_RawMalloc(sizeof(wchar_t*) * (argc+1));
-    argv_copy2 = (wchar_t **)PyMem_RawMalloc(sizeof(wchar_t*) * (argc+1));
-    if (!argv_copy || !argv_copy2) {
-        fatal_error("out of memory");
-        return 1;
-    }
-
-    /* 754 requires that FP exceptions run in "no stop" mode by default,
-     * and until C vendors implement C99's ways to control FP exceptions,
-     * Python requires non-stop mode.  Alas, some platforms enable FP
-     * exceptions by default.  Here we disable them.
-     */
-#ifdef __FreeBSD__
-    fedisableexcept(FE_OVERFLOW);
-#endif
-
-    oldloc = _PyMem_RawStrdup(setlocale(LC_ALL, NULL));
-    if (!oldloc) {
-        fatal_error("out of memory");
-        return 1;
-    }
-
-    /* Reconfigure the locale to the default for this process */
-    _Py_SetLocaleFromEnv(LC_ALL);
-
-    /* The legacy C locale assumes ASCII as the default text encoding, which
-     * causes problems not only for the CPython runtime, but also other
-     * components like GNU readline.
-     *
-     * Accordingly, when the CLI detects it, it attempts to coerce it to a
-     * more capable UTF-8 based alternative.
-     *
-     * See the documentation of the PYTHONCOERCECLOCALE setting for more
-     * details.
-     */
-    if (_Py_LegacyLocaleDetected()) {
-        Py_UTF8Mode = 1;
-        _Py_CoerceLegacyLocale();
-    }
-
-    /* Convert from char to wchar_t based on the locale settings */
-    for (i = 0; i < argc; i++) {
-        argv_copy[i] = Py_DecodeLocale(argv[i], NULL);
-        if (!argv_copy[i]) {
-            PyMem_RawFree(oldloc);
-            fatal_error("unable to decode the command line arguments");
-        }
-        argv_copy2[i] = argv_copy[i];
-    }
-    argv_copy2[argc] = argv_copy[argc] = NULL;
-
-    setlocale(LC_ALL, oldloc);
-    PyMem_RawFree(oldloc);
-
-    status = Py_Main(argc, argv_copy);
-
-    /* Py_Main() can change PyMem_RawMalloc() allocator, so restore the default
-       to release memory blocks allocated before Py_Main() */
-    _PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, NULL);
-
-    for (i = 0; i < argc; i++) {
-        PyMem_RawFree(argv_copy2[i]);
-    }
-    PyMem_RawFree(argv_copy);
-    PyMem_RawFree(argv_copy2);
-    return status;
+    return _Py_UnixMain(argc, argv);
 }
 #endif