AC_INIT(potd, 1.0, matzeton@googlemail.com)
AC_CONFIG_HEADERS([src/config.h])
AC_CANONICAL_TARGET
AM_INIT_AUTOMAKE
AM_SILENT_RULES([yes])
AM_MAINTAINER_MODE

if test -z "$CFLAGS"; then
    CFLAGS="-Os -g"
fi

AC_CANONICAL_HOST
AC_PROG_CC
AC_PROG_CC_STDC
AC_PROG_INSTALL

AC_TYPE_SIZE_T

# check for spectre mitigation
saved_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS -mindirect-branch=thunk"
AC_MSG_CHECKING([if ${CC} supports -mindirect-branch=thunk spectre mitigation])
AC_COMPILE_IFELSE([AC_LANG_SOURCE([char foo;])],
      [ AC_MSG_RESULT([yes])
        SPECTRE_MIT="-mindirect-branch=thunk" ],
        AC_MSG_RESULT([no]))
CFLAGS="$saved_CFLAGS"
AC_SUBST(SPECTRE_MIT)

# check for -fvisibility=hidden compiler support (GCC >= 4)
saved_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS -fvisibility=hidden -fvisibility-inlines-hidden"
AC_MSG_CHECKING([if ${CC} supports -fvisibility=hidden -fvisibility-inlines-hidden])
AC_COMPILE_IFELSE([AC_LANG_SOURCE([char foo;])],
      [ AC_MSG_RESULT([yes])
        SYMBOL_VISIBILITY="-fvisibility=hidden" ],
        AC_MSG_RESULT([no]))
CFLAGS="$saved_CFLAGS"
AC_SUBST(SYMBOL_VISIBILITY)

AC_CHECK_LIB(socket, connect)
AC_CHECK_LIB(pthread, pthread_create)

dnl libssh-dev
PKG_CHECK_MODULES([libssh], [libssh >= 0.7.3])
AC_SUBST([libssh_CFLAGS])
AC_SUBST([libssh_LIBS])

dnl libseccomp-dev
PKG_CHECK_MODULES([libseccomp], [libseccomp >= 2.3.1])
AC_SUBST([libseccomp_CFLAGS])
AC_SUBST([libseccomp_LIBS])

dnl Check for std header files
AC_CHECK_HEADERS([stdio.h stdlib.h unistd.h string.h ctype.h assert.h sched.h signal.h errno.h])

dnl Check for system specific header files
AC_CHECK_HEADERS([pty.h linux/capability.h sys/types.h sys/wait.h sys/stat.h])
AC_CHECK_HEADERS([libutil.h pthread.h pty.h strings.h syslog.h sys/prctl.h \
                  sys/uio.h poll.h sys/epoll.h util.h])

dnl Most systems require linking against libutil.so in order to get forkpty()
AC_CHECK_FUNCS(forkpty, [],
               [AC_CHECK_LIB(util, forkpty,
               [LIBS="-lutil $LIBS"
                AC_DEFINE(HAVE_FORKPTY)])])

AC_OUTPUT(Makefile src/Makefile)