# setlocale_null.m4 serial 2

dnl Copyright (C) 2019-2020 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_SETLOCALE_NULL],

[

  AC_REQUIRE([AC_CANONICAL_HOST])

  AC_REQUIRE([gl_PTHREADLIB])

  AC_CHECK_HEADERS_ONCE([threads.h])

  AC_CACHE_CHECK([whether setlocale (LC_ALL, NULL) is multithread-safe],

    [gl_cv_func_setlocale_null_all_mtsafe],

    [case "$host_os" in

       # Guess no on musl libc, macOS, FreeBSD, NetBSD, OpenBSD, AIX, Haiku, Cygwin.

       *-musl* | darwin* | freebsd* | netbsd* | openbsd* | aix* | haiku* | cygwin*)

         gl_cv_func_setlocale_null_all_mtsafe=no ;;

       # Guess yes on glibc, HP-UX, IRIX, Solaris, native Windows.

       *-gnu* | gnu* | hpux* | irix* | solaris* | mingw*)

         gl_cv_func_setlocale_null_all_mtsafe=yes ;;

       # If we don't know, obey --enable-cross-guesses.

       *)

         gl_cv_func_setlocale_null_all_mtsafe="$gl_cross_guess_normal" ;;

     esac

    ])

  dnl On platforms without multithreading, there is no issue.

  case "$host_os" in

    mingw*) ;;

    *)

      if test $gl_pthread_api = no && test $ac_cv_header_threads_h = no; then

        gl_cv_func_setlocale_null_all_mtsafe="trivially yes"

      fi

      ;;

  esac

  case "$gl_cv_func_setlocale_null_all_mtsafe" in

    *yes) SETLOCALE_NULL_ALL_MTSAFE=1 ;;

    *)    SETLOCALE_NULL_ALL_MTSAFE=0 ;;

  esac

  AC_DEFINE_UNQUOTED([SETLOCALE_NULL_ALL_MTSAFE], [$SETLOCALE_NULL_ALL_MTSAFE],

    [Define to 1 if setlocale (LC_ALL, NULL) is multithread-safe.])

  dnl This is about a single category (not LC_ALL).

  AC_CACHE_CHECK([whether setlocale (category, NULL) is multithread-safe],

    [gl_cv_func_setlocale_null_one_mtsafe],

    [case "$host_os" in

       # Guess no on OpenBSD, AIX.

       openbsd* | aix*)

         gl_cv_func_setlocale_null_one_mtsafe=no ;;

       # Guess yes on glibc, musl libc, macOS, FreeBSD, NetBSD, HP-UX, IRIX, Solaris, Haiku, Cygwin, native Windows.

       *-gnu* | gnu* | *-musl* | darwin* | freebsd* | netbsd* | hpux* | irix* | solaris* | haiku* | cygwin* | mingw*)

         gl_cv_func_setlocale_null_one_mtsafe=yes ;;

       # If we don't know, obey --enable-cross-guesses.

       *)

         gl_cv_func_setlocale_null_one_mtsafe="$gl_cross_guess_normal" ;;

     esac

    ])

  dnl On platforms without multithreading, there is no issue.

  case "$host_os" in

    mingw*) ;;

    *)

      if test $gl_pthread_api = no && test $ac_cv_header_threads_h = no; then

        gl_cv_func_setlocale_null_one_mtsafe="trivially yes"

      fi

      ;;

  esac

  case "$gl_cv_func_setlocale_null_one_mtsafe" in

    *yes) SETLOCALE_NULL_ONE_MTSAFE=1 ;;

    *)    SETLOCALE_NULL_ONE_MTSAFE=0 ;;

  esac

  AC_DEFINE_UNQUOTED([SETLOCALE_NULL_ONE_MTSAFE], [$SETLOCALE_NULL_ONE_MTSAFE],

    [Define to 1 if setlocale (category, NULL) is multithread-safe.])

  dnl Determine link dependencies of lib/setlocale_null.c and lib/setlocale-lock.c.

  if test $SETLOCALE_NULL_ALL_MTSAFE = 0 || test $SETLOCALE_NULL_ONE_MTSAFE = 0; then

    case "$host_os" in

      mingw*) LIB_SETLOCALE_NULL= ;;

      *)

        gl_WEAK_SYMBOLS

        case "$gl_cv_have_weak" in

          *yes) LIB_SETLOCALE_NULL= ;;

          *)    LIB_SETLOCALE_NULL="$LIBPTHREAD" ;;

        esac

        ;;

    esac

  else

    LIB_SETLOCALE_NULL=

  fi

  dnl LIB_SETLOCALE_NULL is expected to be '-pthread' or '-lpthread' on AIX

  dnl with gcc or xlc, and empty otherwise.

  AC_SUBST([LIB_SETLOCALE_NULL])

])

# Prerequisites of lib/setlocale-lock.c.

AC_DEFUN([gl_PREREQ_SETLOCALE_LOCK],

[

  gl_VISIBILITY

])