# gc.m4 serial 1
dnl Copyright (C) 2005 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_GC],
[
  AC_LIBSOURCES([gc.h, gc-gnulib.c, gc-libgcrypt.c])
  AC_ARG_WITH(libgcrypt,
    AS_HELP_STRING([--with-libgcrypt], [use libgcrypt for low-level crypto]),
    libgcrypt=$withval, libgcrypt=no)
  if test "$libgcrypt" != no; then
    AC_LIB_HAVE_LINKFLAGS([gcrypt], [], [#include <gcrypt.h>])
  fi
  if test "$ac_cv_libgcrypt" = yes; then
    AC_LIBOBJ([gc-libgcrypt])
  else
    AC_LIBOBJ([gc-gnulib])

    # Devices with randomness.
    # FIXME: Are these the best defaults?

    case "${target}" in
      *-openbsd*)
  	NAME_OF_RANDOM_DEVICE="/dev/srandom"
  	NAME_OF_PSEUDO_RANDOM_DEVICE="/dev/prandom"
  	NAME_OF_NONCE_DEVICE="/dev/urandom"
          ;;
  
      *-netbsd*)
  	NAME_OF_RANDOM_DEVICE="/dev/srandom"
  	NAME_OF_PSEUDO_RANDOM_DEVICE="/dev/urandom"
  	NAME_OF_NONCE_DEVICE="/dev/urandom"
          ;;
  
      *-solaris* | *-irix* | *-dec-osf* )
  	NAME_OF_RANDOM_DEVICE="/dev/random"
  	NAME_OF_PSEUDO_RANDOM_DEVICE="/dev/random"
  	NAME_OF_NONCE_DEVICE="/dev/random"
          ;;
  
      *)
  	NAME_OF_RANDOM_DEVICE="/dev/random"
  	NAME_OF_PSEUDO_RANDOM_DEVICE="/dev/urandom"
  	NAME_OF_NONCE_DEVICE="/dev/urandom"
          ;;
    esac
  
    AC_MSG_CHECKING([device with (strong) random data...])
    AC_ARG_ENABLE(random-device,
  	AC_HELP_STRING([--enable-random-device],
  		[device with (strong) randomness (for Nettle)]),
  	test "$enableval" != "no" && NAME_OF_RANDOM_DEVICE=$enableval)
    AC_MSG_RESULT($NAME_OF_RANDOM_DEVICE)
  
    AC_MSG_CHECKING([device with pseudo random data...])
    AC_ARG_ENABLE(pseudo-random-device,
  	AC_HELP_STRING([--enable-pseudo-random-device],
  		[device with pseudo randomness (for Nettle)]),
  	test "$enableval" != "no" && NAME_OF_PSEUDO_RANDOM_DEVICE=$enableval)
    AC_MSG_RESULT($NAME_OF_PSEUDO_RANDOM_DEVICE)
  
    AC_MSG_CHECKING([device with unpredictable data for nonces...])
    AC_ARG_ENABLE(nonce-device,
  	AC_HELP_STRING([--enable-nonce-device],
  		[device with unpredictable nonces (for Nettle)]),
  	test "$enableval" != "no" && NAME_OF_NONCE_DEVICE=$enableval)
    AC_MSG_RESULT($NAME_OF_NONCE_DEVICE)
  
    if test "$cross_compiling" != yes; then
      AC_CHECK_FILE($NAME_OF_RANDOM_DEVICE,,
        AC_MSG_ERROR([[device for (strong) random data `$NAME_OF_RANDOM_DEVICE' does not exist]]))
      AC_CHECK_FILE($NAME_OF_PSEUDO_RANDOM_DEVICE,,
        AC_MSG_ERROR([[device for pseudo-random data `$NAME_OF_PSEUDO_RANDOM_DEVICE' does not exist]]))
      AC_CHECK_FILE($NAME_OF_NONCE_DEVICE,,
        AC_MSG_ERROR([[device for unpredictable nonces `$NAME_OF_NONCE_DEVICE' does not exist]]))
    else
      AC_MSG_NOTICE([[Cross compiling, assuming random devices exists...]])  
    fi
  
    # FIXME: Open+read 42 bytes+close twice and compare data.  Should differ.
  
    AC_DEFINE_UNQUOTED(NAME_OF_RANDOM_DEVICE, "$NAME_OF_RANDOM_DEVICE",
                     [defined to the name of the (strong) random device])
    AC_DEFINE_UNQUOTED(NAME_OF_PSEUDO_RANDOM_DEVICE,
  			 "$NAME_OF_PSEUDO_RANDOM_DEVICE",
                     [defined to the name of the pseudo random device])
    AC_DEFINE_UNQUOTED(NAME_OF_NONCE_DEVICE, "$NAME_OF_NONCE_DEVICE",
                     [defined to the name of the unpredictable nonce device])
  fi
])

# Prerequisites of lib/gc.h
AC_DEFUN([gl_PREREQ_GC], [:])