# pty.m4 serial 2
dnl Copyright (C) 2010 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.

# gl_PTY_LIB
# ----------
# Define automake variable PTY_LIB to the library needed (if any).
AC_DEFUN([gl_PTY_LIB],
[
  # Check for the library required for forkpty.
  PTY_LIB=
  save_LIBS="$LIBS"
  AC_SEARCH_LIBS([forkpty], [util],
    [if test "$ac_cv_search_forkpty" != "none required"; then
       PTY_LIB="$ac_cv_search_forkpty"
     fi])
  LIBS="$save_LIBS"
  AC_SUBST([PTY_LIB])
])

AC_DEFUN([gl_FORKPTY],
[
  AC_REQUIRE([gl_PTY_LIB])
  AC_REQUIRE([gl_PTY])

  AC_CHECK_DECLS([forkpty],,, [[
#if HAVE_PTY_H
# include <pty.h>
#endif
#if HAVE_UTIL_H
# include <util.h>
#endif
#if HAVE_LIBUTIL_H
# include <libutil.h>
#endif
]])
  if test $ac_cv_have_decl_forkpty = no; then
    AC_MSG_WARN([[Cannot find forkpty, build will likely fail]])
  fi

  dnl Prefer glibc's const-safe prototype, if available.
  AC_CACHE_CHECK([for const-safe forkpty signature],
    [gl_cv_func_forkpty_const],
    [AC_COMPILE_IFELSE(
      [AC_LANG_PROGRAM([[
#if HAVE_PTY_H
# include <pty.h>
#endif
#if HAVE_UTIL_H
# include <util.h>
#endif
#if HAVE_LIBUTIL_H
# include <libutil.h>
#endif
      ]], [[
        int forkpty (int *, char *, struct termios const *,
                     struct winsize const *);
      ]])],
      [gl_cv_func_forkpty_const=yes], [gl_cv_func_forkpty_const=no])])
  if test $gl_cv_func_forkpty_const != yes; then
    REPLACE_FORKPTY=1
    AC_LIBOBJ([forkpty])
  fi
])

AC_DEFUN([gl_OPENPTY],
[
  AC_REQUIRE([gl_PTY_LIB])
  AC_REQUIRE([gl_PTY])

  AC_CHECK_DECLS([openpty],,, [[
#if HAVE_PTY_H
# include <pty.h>
#endif
#if HAVE_UTIL_H
# include <util.h>
#endif
#if HAVE_LIBUTIL_H
# include <libutil.h>
#endif
]])
  if test $ac_cv_have_decl_openpty = no; then
    AC_MSG_WARN([[Cannot find openpty, build will likely fail]])
  fi

  dnl Prefer glibc's const-safe prototype, if available.
  AC_CACHE_CHECK([for const-safe openpty signature],
    [gl_cv_func_openpty_const],
    [AC_COMPILE_IFELSE(
      [AC_LANG_PROGRAM([[
#if HAVE_PTY_H
# include <pty.h>
#endif
#if HAVE_UTIL_H
# include <util.h>
#endif
#if HAVE_LIBUTIL_H
# include <libutil.h>
#endif
      ]], [[
        int openpty (int *, int *, char *, struct termios const *,
                     struct winsize const *);
      ]])],
      [gl_cv_func_openpty_const=yes], [gl_cv_func_openpty_const=no])])
  if test $gl_cv_func_openpty_const != yes; then
    REPLACE_OPENPTY=1
    AC_LIBOBJ([openpty])
  fi
])