# tsearch.m4 serial 3
dnl Copyright (C) 2006-2008 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_TSEARCH],
[
  AC_REQUIRE([gl_SEARCH_H_DEFAULTS])
  AC_CHECK_FUNCS([tsearch])
  if test $ac_cv_func_tsearch = yes; then
    dnl On OpenBSD 4.0, the return value of tdelete() is incorrect.
    AC_REQUIRE([AC_PROG_CC])
    AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
    AC_CACHE_CHECK([whether tdelete works], [gl_cv_func_tdelete_works],
      [
        AC_TRY_RUN([
#include <stddef.h>
#include <search.h>
static int
cmp_fn (const void *a, const void *b)
{
  return *(const int *) a - *(const int *) b;
}
int
main ()
{
  int x = 0;
  void *root = NULL;
  if (!(tfind (&x, &root, cmp_fn) == NULL)) return 1;
  tsearch (&x, &root, cmp_fn);
  if (!(tfind (&x, &root, cmp_fn) != NULL)) return 1;
  if (!(tdelete (&x, &root, cmp_fn) != NULL)) return 1;
  return 0;
}], [gl_cv_func_tdelete_works=yes], [gl_cv_func_tdelete_works=no],
            [case "$host_os" in
               openbsd*) gl_cv_func_tdelete_works="guessing no";;
               *)        gl_cv_func_tdelete_works="guessing yes";;
             esac
            ])
      ])
    case "$gl_cv_func_tdelete_works" in
      *no)
        REPLACE_TSEARCH=1
        AC_LIBOBJ([tsearch])
        gl_PREREQ_TSEARCH
        ;;
    esac
  else
    HAVE_TSEARCH=0
    AC_LIBOBJ([tsearch])
    gl_PREREQ_TSEARCH
  fi
])

# Prerequisites of lib/tsearch.c.
AC_DEFUN([gl_PREREQ_TSEARCH], [
  :
])