1 files changed, 104 insertions, 0 deletions
diff --git a/m4/wcwidth.m4 b/m4/wcwidth.m4
new file mode 100644
index 0000000..7a743c0
--- /dev/null
+++ b/m4/wcwidth.m4
@@ -0,0 +1,104 @@
+# wcwidth.m4 serial 23
+dnl Copyright (C) 2006-2016 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.
+
+AC_DEFUN([gl_FUNC_WCWIDTH],
+[
+  AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
+  dnl Persuade glibc <wchar.h> to declare wcwidth().
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
+
+  AC_REQUIRE([gt_TYPE_WCHAR_T])
+  AC_REQUIRE([gt_TYPE_WINT_T])
+
+  AC_CHECK_HEADERS_ONCE([wchar.h])
+  AC_CHECK_FUNCS_ONCE([wcwidth])
+
+  AC_CHECK_DECLS([wcwidth], [], [], [[
+/* AIX 3.2.5 declares wcwidth in <string.h>. */
+#include <string.h>
+/* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
+   <wchar.h>.
+   BSD/OS 4.0.1 has a bug: <stddef.h>, <stdio.h> and <time.h> must be included
+   before <wchar.h>.  */
+#include <stddef.h>
+#include <stdio.h>
+#include <time.h>
+#include <wchar.h>
+]])
+  if test $ac_cv_have_decl_wcwidth != yes; then
+    HAVE_DECL_WCWIDTH=0
+  fi
+
+  if test $ac_cv_func_wcwidth = yes; then
+    HAVE_WCWIDTH=1
+    dnl On Mac OS X 10.3, wcwidth(0x0301) (COMBINING ACUTE ACCENT) returns 1.
+    dnl On OpenBSD 5.0, wcwidth(0x05B0) (HEBREW POINT SHEVA) returns 1.
+    dnl On OSF/1 5.1, wcwidth(0x200B) (ZERO WIDTH SPACE) returns 1.
+    dnl On OpenBSD 5.8, wcwidth(0xFF1A) (FULLWIDTH COLON) returns 0.
+    dnl This leads to bugs in 'ls' (coreutils).
+    AC_CACHE_CHECK([whether wcwidth works reasonably in UTF-8 locales],
+      [gl_cv_func_wcwidth_works],
+      [
+        AC_RUN_IFELSE(
+          [AC_LANG_SOURCE([[
+#include <locale.h>
+/* AIX 3.2.5 declares wcwidth in <string.h>. */
+#include <string.h>
+/* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
+   <wchar.h>.
+   BSD/OS 4.0.1 has a bug: <stddef.h>, <stdio.h> and <time.h> must be included
+   before <wchar.h>.  */
+#include <stddef.h>
+#include <stdio.h>
+#include <time.h>
+#include <wchar.h>
+#if !HAVE_DECL_WCWIDTH
+extern
+# ifdef __cplusplus
+"C"
+# endif
+int wcwidth (int);
+#endif
+int main ()
+{
+  int result = 0;
+  if (setlocale (LC_ALL, "fr_FR.UTF-8") != NULL)
+    {
+      if (wcwidth (0x0301) > 0)
+        result |= 1;
+      if (wcwidth (0x05B0) > 0)
+        result |= 2;
+      if (wcwidth (0x200B) > 0)
+        result |= 4;
+      if (wcwidth (0xFF1A) == 0)
+        result |= 8;
+    }
+  return result;
+}]])],
+          [gl_cv_func_wcwidth_works=yes],
+          [gl_cv_func_wcwidth_works=no],
+          [
+changequote(,)dnl
+           case "$host_os" in
+                     # Guess yes on glibc and AIX 7 systems.
+             *-gnu* | aix[7-9]*) gl_cv_func_wcwidth_works="guessing yes";;
+             *)                  gl_cv_func_wcwidth_works="guessing no";;
+           esac
+changequote([,])dnl
+          ])
+      ])
+    case "$gl_cv_func_wcwidth_works" in
+      *yes) ;;
+      *no) REPLACE_WCWIDTH=1 ;;
+    esac
+  else
+    HAVE_WCWIDTH=0
+  fi
+  dnl We don't substitute HAVE_WCWIDTH. We assume that if the system does not
+  dnl have the wcwidth function, then it does not declare it.
+])