dnl A placeholder for ISO C99 <wchar.h>, for platforms that have issues.

dnl Copyright (C) 2007-2011 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.

dnl Written by Eric Blake.

# wchar_h.m4 serial 38

AC_DEFUN([gl_WCHAR_H],
[
  AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
  AC_REQUIRE([gl_WCHAR_H_INLINE_OK])
  dnl Prepare for creating substitute <wchar.h>.
  dnl Check for <wchar.h> (missing in Linux uClibc when built without wide
  dnl character support).
  dnl <wchar.h> is always overridden, because of GNULIB_POSIXCHECK.
  gl_CHECK_NEXT_HEADERS([wchar.h])
  if test $ac_cv_header_wchar_h = yes; then
    HAVE_WCHAR_H=1
  else
    HAVE_WCHAR_H=0
  fi
  AC_SUBST([HAVE_WCHAR_H])

  AC_REQUIRE([gl_FEATURES_H])

  AC_REQUIRE([gt_TYPE_WINT_T])
  if test $gt_cv_c_wint_t = yes; then
    HAVE_WINT_T=1
  else
    HAVE_WINT_T=0
  fi
  AC_SUBST([HAVE_WINT_T])

  dnl Check for declarations of anything we want to poison if the
  dnl corresponding gnulib module is not in use.
  gl_WARN_ON_USE_PREPARE([[
/* 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>.  */
#if !(defined __GLIBC__ && !defined __UCLIBC__)
# include <stddef.h>
# include <stdio.h>
# include <time.h>
#endif
#include <wchar.h>
    ]],
    [btowc wctob mbsinit mbrtowc mbrlen mbsrtowcs mbsnrtowcs wcrtomb
     wcsrtombs wcsnrtombs wcwidth wmemchr wmemcmp wmemcpy wmemmove wmemset
     wcslen wcsnlen wcscpy wcpcpy wcsncpy wcpncpy wcscat wcsncat wcscmp
    ])
])

dnl Check whether <wchar.h> is usable at all.
AC_DEFUN([gl_WCHAR_H_INLINE_OK],
[
  dnl Test whether <wchar.h> suffers due to the transition from '__inline' to
  dnl 'gnu_inline'. See <http://sourceware.org/bugzilla/show_bug.cgi?id=4022>
  dnl and <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42440>. In summary,
  dnl glibc version 2.5 or older, together with gcc version 4.3 or newer and
  dnl the option -std=c99 or -std=gnu99, leads to a broken <wchar.h>.
  AC_CACHE_CHECK([whether <wchar.h> uses 'inline' correctly],
    [gl_cv_header_wchar_h_correct_inline],
    [gl_cv_header_wchar_h_correct_inline=yes
     AC_LANG_CONFTEST([
       AC_LANG_SOURCE([[#define wcstod renamed_wcstod
/* 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>
extern int zero (void);
int main () { return zero(); }
]])])
     if AC_TRY_EVAL([ac_compile]); then
       mv conftest.$ac_objext conftest1.$ac_objext
       AC_LANG_CONFTEST([
         AC_LANG_SOURCE([[#define wcstod renamed_wcstod
/* 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>
int zero (void) { return 0; }
]])])
       if AC_TRY_EVAL([ac_compile]); then
         mv conftest.$ac_objext conftest2.$ac_objext
         if $CC -o conftest$ac_exeext $CFLAGS $LDFLAGS conftest1.$ac_objext conftest2.$ac_objext $LIBS >&AS_MESSAGE_LOG_FD 2>&1; then
           :
         else
           gl_cv_header_wchar_h_correct_inline=no
         fi
       fi
     fi
     rm -f conftest1.$ac_objext conftest2.$ac_objext conftest$ac_exeext
    ])
  if test $gl_cv_header_wchar_h_correct_inline = no; then
    AC_MSG_ERROR([<wchar.h> cannot be used with this compiler ($CC $CFLAGS $CPPFLAGS).
This is a known interoperability problem of glibc <= 2.5 with gcc >= 4.3 in
C99 mode. You have four options:
  - Add the flag -fgnu89-inline to CC and reconfigure, or
  - Fix your include files, using parts of
    <http://sourceware.org/git/?p=glibc.git;a=commitdiff;h=b037a293a48718af30d706c2e18c929d0e69a621>, or
  - Use a gcc version older than 4.3, or
  - Don't use the flags -std=c99 or -std=gnu99.
Configuration aborted.])
  fi
])

dnl Unconditionally enables the replacement of <wchar.h>.
AC_DEFUN([gl_REPLACE_WCHAR_H],
[
  dnl This is a no-op, because <wchar.h> is always overridden.
  :
])

AC_DEFUN([gl_WCHAR_MODULE_INDICATOR],
[
  dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
  AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
  gl_MODULE_INDICATOR_SET_VARIABLE([$1])
  dnl Define it also as a C macro, for the benefit of the unit tests.
  gl_MODULE_INDICATOR_FOR_TESTS([$1])
])

AC_DEFUN([gl_WCHAR_H_DEFAULTS],
[
  GNULIB_BTOWC=0;      AC_SUBST([GNULIB_BTOWC])
  GNULIB_WCTOB=0;      AC_SUBST([GNULIB_WCTOB])
  GNULIB_MBSINIT=0;    AC_SUBST([GNULIB_MBSINIT])
  GNULIB_MBRTOWC=0;    AC_SUBST([GNULIB_MBRTOWC])
  GNULIB_MBRLEN=0;     AC_SUBST([GNULIB_MBRLEN])
  GNULIB_MBSRTOWCS=0;  AC_SUBST([GNULIB_MBSRTOWCS])
  GNULIB_MBSNRTOWCS=0; AC_SUBST([GNULIB_MBSNRTOWCS])
  GNULIB_WCRTOMB=0;    AC_SUBST([GNULIB_WCRTOMB])
  GNULIB_WCSRTOMBS=0;  AC_SUBST([GNULIB_WCSRTOMBS])
  GNULIB_WCSNRTOMBS=0; AC_SUBST([GNULIB_WCSNRTOMBS])
  GNULIB_WCWIDTH=0;    AC_SUBST([GNULIB_WCWIDTH])
  GNULIB_WMEMCHR=0;    AC_SUBST([GNULIB_WMEMCHR])
  GNULIB_WMEMCMP=0;    AC_SUBST([GNULIB_WMEMCMP])
  GNULIB_WMEMCPY=0;    AC_SUBST([GNULIB_WMEMCPY])
  GNULIB_WMEMMOVE=0;   AC_SUBST([GNULIB_WMEMMOVE])
  GNULIB_WMEMSET=0;    AC_SUBST([GNULIB_WMEMSET])
  GNULIB_WCSLEN=0;     AC_SUBST([GNULIB_WCSLEN])
  GNULIB_WCSNLEN=0;    AC_SUBST([GNULIB_WCSNLEN])
  GNULIB_WCSCPY=0;     AC_SUBST([GNULIB_WCSCPY])
  GNULIB_WCPCPY=0;     AC_SUBST([GNULIB_WCPCPY])
  GNULIB_WCSNCPY=0;    AC_SUBST([GNULIB_WCSNCPY])
  GNULIB_WCPNCPY=0;    AC_SUBST([GNULIB_WCPNCPY])
  GNULIB_WCSCAT=0;     AC_SUBST([GNULIB_WCSCAT])
  GNULIB_WCSNCAT=0;    AC_SUBST([GNULIB_WCSNCAT])
  GNULIB_WCSCMP=0;     AC_SUBST([GNULIB_WCSCMP])
  dnl Assume proper GNU behavior unless another module says otherwise.
  HAVE_BTOWC=1;         AC_SUBST([HAVE_BTOWC])
  HAVE_MBSINIT=1;       AC_SUBST([HAVE_MBSINIT])
  HAVE_MBRTOWC=1;       AC_SUBST([HAVE_MBRTOWC])
  HAVE_MBRLEN=1;        AC_SUBST([HAVE_MBRLEN])
  HAVE_MBSRTOWCS=1;     AC_SUBST([HAVE_MBSRTOWCS])
  HAVE_MBSNRTOWCS=1;    AC_SUBST([HAVE_MBSNRTOWCS])
  HAVE_WCRTOMB=1;       AC_SUBST([HAVE_WCRTOMB])
  HAVE_WCSRTOMBS=1;     AC_SUBST([HAVE_WCSRTOMBS])
  HAVE_WCSNRTOMBS=1;    AC_SUBST([HAVE_WCSNRTOMBS])
  HAVE_WMEMCHR=1;       AC_SUBST([HAVE_WMEMCHR])
  HAVE_WMEMCMP=1;       AC_SUBST([HAVE_WMEMCMP])
  HAVE_WMEMCPY=1;       AC_SUBST([HAVE_WMEMCPY])
  HAVE_WMEMMOVE=1;      AC_SUBST([HAVE_WMEMMOVE])
  HAVE_WMEMSET=1;       AC_SUBST([HAVE_WMEMSET])
  HAVE_WCSLEN=1;        AC_SUBST([HAVE_WCSLEN])
  HAVE_WCSNLEN=1;       AC_SUBST([HAVE_WCSNLEN])
  HAVE_WCSCPY=1;        AC_SUBST([HAVE_WCSCPY])
  HAVE_WCPCPY=1;        AC_SUBST([HAVE_WCPCPY])
  HAVE_WCSNCPY=1;       AC_SUBST([HAVE_WCSNCPY])
  HAVE_WCPNCPY=1;       AC_SUBST([HAVE_WCPNCPY])
  HAVE_WCSCAT=1;        AC_SUBST([HAVE_WCSCAT])
  HAVE_WCSNCAT=1;       AC_SUBST([HAVE_WCSNCAT])
  HAVE_WCSCMP=1;        AC_SUBST([HAVE_WCSCMP])
  HAVE_DECL_WCTOB=1;    AC_SUBST([HAVE_DECL_WCTOB])
  HAVE_DECL_WCWIDTH=1;  AC_SUBST([HAVE_DECL_WCWIDTH])
  REPLACE_MBSTATE_T=0;  AC_SUBST([REPLACE_MBSTATE_T])
  REPLACE_BTOWC=0;      AC_SUBST([REPLACE_BTOWC])
  REPLACE_WCTOB=0;      AC_SUBST([REPLACE_WCTOB])
  REPLACE_MBSINIT=0;    AC_SUBST([REPLACE_MBSINIT])
  REPLACE_MBRTOWC=0;    AC_SUBST([REPLACE_MBRTOWC])
  REPLACE_MBRLEN=0;     AC_SUBST([REPLACE_MBRLEN])
  REPLACE_MBSRTOWCS=0;  AC_SUBST([REPLACE_MBSRTOWCS])
  REPLACE_MBSNRTOWCS=0; AC_SUBST([REPLACE_MBSNRTOWCS])
  REPLACE_WCRTOMB=0;    AC_SUBST([REPLACE_WCRTOMB])
  REPLACE_WCSRTOMBS=0;  AC_SUBST([REPLACE_WCSRTOMBS])
  REPLACE_WCSNRTOMBS=0; AC_SUBST([REPLACE_WCSNRTOMBS])
  REPLACE_WCWIDTH=0;    AC_SUBST([REPLACE_WCWIDTH])
])