getlogin_r: Small fixes.

[gnulib.git] / m4 / btowc.m4

diff --git a/m4/btowc.m4 b/m4/btowc.m4
index a53694a..2c75c8f 100644 (file)
--- a/m4/btowc.m4
+++ b/m4/btowc.m4
@@ -1,5 +1,5 @@
-# btowc.m4 serial 2
-dnl Copyright (C) 2008 Free Software Foundation, Inc.
+# btowc.m4 serial 5
+dnl Copyright (C) 2008-2010 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -8,9 +8,59 @@ AC_DEFUN([gl_FUNC_BTOWC],
 [
   AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
 
+  dnl Check whether <wchar.h> is usable at all, first. Otherwise the test
+  dnl program below may lead to an endless loop. See
+  dnl <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42440>.
+  AC_REQUIRE([gl_WCHAR_H_INLINE_OK])
+
   AC_CHECK_FUNCS_ONCE([btowc])
   if test $ac_cv_func_btowc = no; then
     HAVE_BTOWC=0
+  else
+
+    dnl IRIX 6.5 btowc(EOF) is 0xFF, not WEOF.
+    AC_REQUIRE([AC_PROG_CC])
+    AC_REQUIRE([gt_LOCALE_FR])
+    AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+    AC_CACHE_CHECK([whether btowc(EOF) is correct],
+      [gl_cv_func_btowc_eof],
+      [
+        dnl Initial guess, used when cross-compiling or when no suitable locale
+        dnl is present.
+changequote(,)dnl
+        case "$host_os" in
+                 # Guess no on IRIX.
+          irix*) gl_cv_func_btowc_eof="guessing no" ;;
+                 # Guess yes otherwise.
+          *)     gl_cv_func_btowc_eof="guessing yes" ;;
+        esac
+changequote([,])dnl
+        if test $LOCALE_FR != none; then
+          AC_TRY_RUN([
+#include <locale.h>
+#include <stdio.h>
+#include <string.h>
+#include <wchar.h>
+int main ()
+{
+  if (setlocale (LC_ALL, "$LOCALE_FR") != NULL)
+    {
+      if (btowc (EOF) != WEOF)
+        return 1;
+    }
+  return 0;
+}],
+            [gl_cv_func_btowc_eof=yes],
+            [gl_cv_func_btowc_eof=no],
+            [:])
+        fi
+      ])
+    case "$gl_cv_func_btowc_eof" in
+      *yes) ;;
+      *) REPLACE_BTOWC=1 ;;
+    esac
+  fi
+  if test $HAVE_BTOWC = 0 || test $REPLACE_BTOWC = 1; then
     gl_REPLACE_WCHAR_H
     AC_LIBOBJ([btowc])
     gl_PREREQ_BTOWC