[libcxx] Split locale management out of newlib/xlocale.h. NFCI

[bcraig]

Summary

This is one part of many of a locale refactor. See http://reviews.llvm.org/D17146 for an idea of where this is going.

For the locale refactor, the locale management functions (newlocale, freelocale, uselocale) are needed in a separate header from the various _l functions. This is because some platforms implement the _l functions in terms of a locale switcher RAII helper, and the locale switcher RAII helper needs the locale management functions. This patch helps pave the way by getting all the functions in the right files, so that later diffs aren't completely horrible.

The "do-nothing" / "nop" locale functions are also useful on their own for other lightweight platforms. Putting these nop implementations in support/xlocale should enable code sharing.

Unfortunately, I have no access to a newlib system to build and test with, so this change has been made blind.

[jroelofs]

LGTM

include/support/newlib/xlocale.h

 #include <clocale>
 #include <cwctype>
 #include <ctype.h>
+#include <support/xlocale/__nop_locale_mgmt.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-// Patch over newlib's lack of extended locale support
-typedef void *locale_t;
-static inline locale_t duplocale(locale_t) {
-  return NULL;
-}
-
-static inline void freelocale(locale_t) {
-}
-
-static inline locale_t newlocale(int, const char *, locale_t) {
-  return NULL;
-}
-
-static inline locale_t uselocale(locale_t) {
-  return NULL;
-}
-
-#define LC_COLLATE_MASK  (1 << LC_COLLATE)
-#define LC_CTYPE_MASK    (1 << LC_CTYPE)
-#define LC_MESSAGES_MASK (1 << LC_MESSAGES)
-#define LC_MONETARY_MASK (1 << LC_MONETARY)
-#define LC_NUMERIC_MASK  (1 << LC_NUMERIC)
-#define LC_TIME_MASK     (1 << LC_TIME)
-#define LC_ALL_MASK (LC_COLLATE_MASK|\
-                     LC_CTYPE_MASK|\
-                     LC_MONETARY_MASK|\
-                     LC_NUMERIC_MASK|\
-                     LC_TIME_MASK|\
-                     LC_MESSAGES_MASK)
-
 // Share implementation with Android's Bionic
 #include <support/xlocale/xlocale.h>
 

include/support/xlocale/__nop_locale_mgmt.h

+// -*- C++ -*-
+//===------------  support/xlocale/__nop_locale_mgmt.h -----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SUPPORT_XLOCALE_NOP_LOCALE_MGMT_H
+#define _LIBCPP_SUPPORT_XLOCALE_NOP_LOCALE_MGMT_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Patch over lack of extended locale support
+typedef void *locale_t;
+static inline locale_t duplocale(locale_t) {
+  return NULL;
+}
+
+static inline void freelocale(locale_t) {
+}
+
+static inline locale_t newlocale(int, const char *, locale_t) {
+  return NULL;
+}
+
+static inline locale_t uselocale(locale_t) {
+  return NULL;
+}
+
+#define LC_COLLATE_MASK  (1 << LC_COLLATE)
+#define LC_CTYPE_MASK    (1 << LC_CTYPE)
+#define LC_MESSAGES_MASK (1 << LC_MESSAGES)
+#define LC_MONETARY_MASK (1 << LC_MONETARY)
+#define LC_NUMERIC_MASK  (1 << LC_NUMERIC)
+#define LC_TIME_MASK     (1 << LC_TIME)
+#define LC_ALL_MASK (LC_COLLATE_MASK|\
+                     LC_CTYPE_MASK|\
+                     LC_MONETARY_MASK|\
+                     LC_NUMERIC_MASK|\
+                     LC_TIME_MASK|\
+                     LC_MESSAGES_MASK)
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif // _LIBCPP_SUPPORT_XLOCALE_NOP_LOCALE_MGMT_H