Refactor <locale> RAII guards to aid upcoming Windows locale changes.

Previously <locale> used std::unique_ptr<remove_ptr<locale_t>, locale-mgmt-function>
as a scope guard for (A) creating new locales, and (B) setting the thread specific locale
in RAII safe manner.

However using unique_ptr has some problems, first it requires that locale_t is a pointer
type, which may not be the case (Windows will need a non-pointer locale_t type that emulates _locale_t).

The second problem is that users of the guards had to supply the locale management function to the custom
deleter at every call site. However these locale management functions don't exist natively Windows, making
a good Windows implementation of locale more difficult.

This patch creates distinct and simply RAII guards that replace unique_ptr. These guards handle calling
the correct locale management function so that callers don't have too. This simplification will
aid in upcoming Windows fixes.

llvm-svn: 302474

1 files changed, 14 insertions, 17 deletions

diff --git a/libcxx/include/__bsd_locale_fallbacks.h b/libcxx/include/__bsd_locale_fallbacks.h
index cbc8ad226fd..3425ce659b7 100644
--- a/libcxx/include/__bsd_locale_fallbacks.h
+++ b/libcxx/include/__bsd_locale_fallbacks.h
@@ -19,27 +19,24 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-typedef _VSTD::remove_pointer<locale_t>::type __use_locale_struct;
-typedef _VSTD::unique_ptr<__use_locale_struct, decltype(&uselocale)> __locale_raii;
-
 inline _LIBCPP_ALWAYS_INLINE
 decltype(MB_CUR_MAX) __libcpp_mb_cur_max_l(locale_t __l)
 {
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     return MB_CUR_MAX;
 }
 
 inline _LIBCPP_ALWAYS_INLINE
 wint_t __libcpp_btowc_l(int __c, locale_t __l)
 {
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     return btowc(__c);
 }
 
 inline _LIBCPP_ALWAYS_INLINE
 int __libcpp_wctob_l(wint_t __c, locale_t __l)
 {
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     return wctob(__c);
 }
 
@@ -47,14 +44,14 @@ inline _LIBCPP_ALWAYS_INLINE
 size_t __libcpp_wcsnrtombs_l(char *__dest, const wchar_t **__src, size_t __nwc,
                          size_t __len, mbstate_t *__ps, locale_t __l)
 {
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     return wcsnrtombs(__dest, __src, __nwc, __len, __ps);
 }
 
 inline _LIBCPP_ALWAYS_INLINE
 size_t __libcpp_wcrtomb_l(char *__s, wchar_t __wc, mbstate_t *__ps, locale_t __l)
 {
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     return wcrtomb(__s, __wc, __ps);
 }
 
@@ -62,7 +59,7 @@ inline _LIBCPP_ALWAYS_INLINE
 size_t __libcpp_mbsnrtowcs_l(wchar_t * __dest, const char **__src, size_t __nms,
                       size_t __len, mbstate_t *__ps, locale_t __l)
 {
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     return mbsnrtowcs(__dest, __src, __nms, __len, __ps);
 }
 
@@ -70,28 +67,28 @@ inline _LIBCPP_ALWAYS_INLINE
 size_t __libcpp_mbrtowc_l(wchar_t *__pwc, const char *__s, size_t __n,
                    mbstate_t *__ps, locale_t __l)
 {
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     return mbrtowc(__pwc, __s, __n, __ps);
 }
 
 inline _LIBCPP_ALWAYS_INLINE
 int __libcpp_mbtowc_l(wchar_t *__pwc, const char *__pmb, size_t __max, locale_t __l)
 {
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     return mbtowc(__pwc, __pmb, __max);
 }
 
 inline _LIBCPP_ALWAYS_INLINE
 size_t __libcpp_mbrlen_l(const char *__s, size_t __n, mbstate_t *__ps, locale_t __l)
 {
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     return mbrlen(__s, __n, __ps);
 }
 
 inline _LIBCPP_ALWAYS_INLINE
 lconv *__libcpp_localeconv_l(locale_t __l)
 {
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     return localeconv();
 }
 
@@ -99,7 +96,7 @@ inline _LIBCPP_ALWAYS_INLINE
 size_t __libcpp_mbsrtowcs_l(wchar_t *__dest, const char **__src, size_t __len,
                      mbstate_t *__ps, locale_t __l)
 {
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     return mbsrtowcs(__dest, __src, __len, __ps);
 }
 
@@ -107,7 +104,7 @@ inline
 int __libcpp_snprintf_l(char *__s, size_t __n, locale_t __l, const char *__format, ...) {
     va_list __va;
     va_start(__va, __format);
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     int __res = vsnprintf(__s, __n, __format, __va);
     va_end(__va);
     return __res;
@@ -117,7 +114,7 @@ inline
 int __libcpp_asprintf_l(char **__s, locale_t __l, const char *__format, ...) {
     va_list __va;
     va_start(__va, __format);
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     int __res = vasprintf(__s, __format, __va);
     va_end(__va);
     return __res;
@@ -127,7 +124,7 @@ inline
 int __libcpp_sscanf_l(const char *__s, locale_t __l, const char *__format, ...) {
     va_list __va;
     va_start(__va, __format);
-    __locale_raii __current( uselocale(__l), uselocale );
+    __libcpp_locale_guard __current(__l);
     int __res = vsscanf(__s, __format, __va);
     va_end(__va);
     return __res;