From 1293cd8b6ab48ff2df4949f261b89c92158af9db Mon Sep 17 00:00:00 2001
From: David Adam <zanchey@ucc.gu.uwa.edu.au>
Date: Tue, 15 Nov 2016 12:12:23 +0800
Subject: [PATCH] Check for functions in std namespace

On Solaris, some standard wide character functions are only contained in
the std:: namespace. The configure script now checks for these, enabling
the appropriate `uses` statements in src/common.h.

The checks are handwritten, because Autoconf's AC_CHECK_FUNC macro
always uses C linkage, but the problem only appears under C++ linkage.

Work on #3340.
---
 configure.ac | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/common.h | 12 +++++++++++
 2 files changed, 68 insertions(+)

diff --git a/configure.ac b/configure.ac
index 6f58a0756..c35d67709 100644
--- a/configure.ac
+++ b/configure.ac
@@ -314,6 +314,62 @@ AC_CHECK_FUNCS( getpwent )
 
 AC_CHECK_DECL( [mkostemp], [ AC_CHECK_FUNCS([mkostemp]) ] )
 
+dnl AC_CHECK_FUNCS uses C linkage, but sometimes (Solaris!) the behaviour is
+dnl different with C++.
+AC_MSG_CHECKING([for wcsdup])
+AC_TRY_LINK( [ #include <wchar.h> ],
+             [ wchar_t* foo = wcsdup(L""); ],
+             [ AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_WCSDUP, 1, Define to 1 if you have the `wcsdup' function.)
+             ],
+             [AC_MSG_RESULT(no)],
+             )
+
+AC_MSG_CHECKING([for std::wcsdup])
+AC_TRY_LINK( [ #include <wchar.h> ],
+             [ wchar_t* foo = std::wcsdup(L""); ],
+             [ AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_STD__WCSDUP, 1, Define to 1 if you have the `std::wcsdup' function.)
+             ],
+             [AC_MSG_RESULT(no)],
+             )
+
+AC_MSG_CHECKING([for wcscasecmp])
+AC_TRY_LINK( [ #include <wchar.h> ],
+             [ int foo = wcscasecmp(L"", L""); ],
+             [ AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_WCSCASECMP, 1, Define to 1 if you have the `wcscasecmp' function.)
+             ],
+             [AC_MSG_RESULT(no)],
+             )
+
+AC_MSG_CHECKING([for std::wcscasecmp])
+AC_TRY_LINK( [ #include <wchar.h> ],
+             [ int foo = std::wcscasecmp(L"", L""); ],
+             [ AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_STD__WCSCASECMP, 1, Define to 1 if you have the `std::wcscasecmp' function.)
+             ],
+             [AC_MSG_RESULT(no)],
+             )
+
+AC_MSG_CHECKING([for wcsncasecmp])
+AC_TRY_LINK( [ #include <wchar.h> ],
+             [ int foo = wcsncasecmp(L"", L"", 0); ],
+             [ AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_WCSNCASECMP, 1, Define to 1 if you have the `wcsncasecmp' function.)
+             ],
+             [AC_MSG_RESULT(no)],
+             )
+
+AC_MSG_CHECKING([for std::wcsncasecmp])
+AC_TRY_LINK( [ #include <wchar.h> ],
+             [ int foo = std::wcsncasecmp(L"", L"", 0); ],
+             [ AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_STD__WCSNCASECMP, 1, Define to 1 if you have the `std::wcsncasecmp' function.)
+             ],
+             [AC_MSG_RESULT(no)],
+             )
+
 if test x$local_gettext != xno; then
   AC_CHECK_FUNCS( gettext )
 
diff --git a/src/common.h b/src/common.h
index dcf43ac65..61af1e9cc 100644
--- a/src/common.h
+++ b/src/common.h
@@ -825,4 +825,16 @@ static const wchar_t *enum_to_str(T enum_val, const enum_map<T> map[]) {
     return NULL;
 };
 
+#if !defined(HAVE_WCSDUP) && defined(HAVE_STD__WCSDUP)
+using std::wcsdup;
+#endif
+
+#if !defined(HAVE_WCSCASECMP) && defined(HAVE_STD__WCSCASECMP)
+using std::wcscasecmp;
+#endif
+
+#if !defined(HAVE_WCSNCASECMP) && defined(HAVE_STD__WCSNCASECMP)
+using std::wcsncasecmp;
+#endif
+
 #endif