m4/wcwidth.m4

   1 # wcwidth.m4 serial 23
   2 dnl Copyright (C) 2006-2013 Free Software Foundation, Inc.
   3 dnl This file is free software; the Free Software Foundation
   4 dnl gives unlimited permission to copy and/or distribute it,
   5 dnl with or without modifications, as long as this notice is preserved.
   6
   7 AC_DEFUN([gl_FUNC_WCWIDTH],
   8 [
   9   AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
  10   AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
  11
  12   dnl Persuade glibc <wchar.h> to declare wcwidth().
  13   AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
  14
  15   AC_REQUIRE([gt_TYPE_WCHAR_T])
  16   AC_REQUIRE([gt_TYPE_WINT_T])
  17
  18   AC_CHECK_HEADERS_ONCE([wchar.h])
  19   AC_CHECK_FUNCS_ONCE([wcwidth])
  20
  21   AC_CHECK_DECLS([wcwidth], [], [], [[
  22 /* AIX 3.2.5 declares wcwidth in <string.h>. */
  23 #include <string.h>
  24 /* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
  25    <wchar.h>.
  26    BSD/OS 4.0.1 has a bug: <stddef.h>, <stdio.h> and <time.h> must be included
  27    before <wchar.h>.  */
  28 #include <stddef.h>
  29 #include <stdio.h>
  30 #include <time.h>
  31 #include <wchar.h>
  32 ]])
  33   if test $ac_cv_have_decl_wcwidth != yes; then
  34     HAVE_DECL_WCWIDTH=0
  35   fi
  36
  37   if test $ac_cv_func_wcwidth = yes; then
  38     HAVE_WCWIDTH=1
  39     dnl On Mac OS X 10.3, wcwidth(0x0301) (COMBINING ACUTE ACCENT) returns 1.
  40     dnl On OpenBSD 5.0, wcwidth(0x05B0) (HEBREW POINT SHEVA) returns 1.
  41     dnl On OSF/1 5.1, wcwidth(0x200B) (ZERO WIDTH SPACE) returns 1.
  42     dnl This leads to bugs in 'ls' (coreutils).
  43     AC_CACHE_CHECK([whether wcwidth works reasonably in UTF-8 locales],
  44       [gl_cv_func_wcwidth_works],
  45       [
  46         AC_RUN_IFELSE(
  47           [AC_LANG_SOURCE([[
  48 #include <locale.h>
  49 /* AIX 3.2.5 declares wcwidth in <string.h>. */
  50 #include <string.h>
  51 /* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
  52    <wchar.h>.
  53    BSD/OS 4.0.1 has a bug: <stddef.h>, <stdio.h> and <time.h> must be included
  54    before <wchar.h>.  */
  55 #include <stddef.h>
  56 #include <stdio.h>
  57 #include <time.h>
  58 #include <wchar.h>
  59 #if !HAVE_DECL_WCWIDTH
  60 extern
  61 # ifdef __cplusplus
  62 "C"
  63 # endif
  64 int wcwidth (int);
  65 #endif
  66 int main ()
  67 {
  68   int result = 0;
  69   if (setlocale (LC_ALL, "fr_FR.UTF-8") != NULL)
  70     {
  71       if (wcwidth (0x0301) > 0)
  72         result |= 1;
  73       if (wcwidth (0x05B0) > 0)
  74         result |= 2;
  75       if (wcwidth (0x200B) > 0)
  76         result |= 4;
  77     }
  78   return result;
  79 }]])],
  80           [gl_cv_func_wcwidth_works=yes],
  81           [gl_cv_func_wcwidth_works=no],
  82           [
  83 changequote(,)dnl
  84            case "$host_os" in
  85                      # Guess yes on glibc and AIX 7 systems.
  86              *-gnu* | aix[7-9]*) gl_cv_func_wcwidth_works="guessing yes";;
  87              *)                  gl_cv_func_wcwidth_works="guessing no";;
  88            esac
  89 changequote([,])dnl
  90           ])
  91       ])
  92     case "$gl_cv_func_wcwidth_works" in
  93       *yes) ;;
  94       *no) REPLACE_WCWIDTH=1 ;;
  95     esac
  96   else
  97     HAVE_WCWIDTH=0
  98   fi
  99   dnl We don't substitute HAVE_WCWIDTH. We assume that if the system does not
 100   dnl have the wcwidth function, then it does not declare it.
 101 ])