configure*: Move AC_SUBST calls to more obvious places

These macros should always be called regardless of the intended value of
each variable, as even if e.g.: no --enable-apparmor flag is given, the
configure script still has to substitute `@HAVE_APPARMOR@` with blank in
the relevant files.

Something similar is already being done for HAVE_OVERLAYFS since commit
fb9f2a5fb ("disabled overlayfs, fixes pending; added video channels to
README* files", 2021-02-06).

Note that each AC_SUBST is not immediately converted into search/replace
code when generating the configure script.  It appears that the
variables are handled only after parsing all of configure.ac (or until a
specific command is found), as all arguments passed to every AC_SUBST
call are defined at once on the `ac_subst_vars` list.  The actual
substitutions are also done all at once (while iterating through the
list) and that happens much later in the script (see both occurrences of
`ac_subs_vars` on the current script).

1 files changed, 21 insertions, 23 deletions

diff --git a/configure.ac b/configure.ac
index 3f3d41bb9..20b60b522 100644
--- a/configure.ac
+++ b/configure.ac
@@ -57,22 +57,22 @@ AS_IF([test "x$enable_sanitizer" != "xno" ],
 )])
 
 HAVE_APPARMOR=""
+AC_SUBST([HAVE_APPARMOR])
 AC_ARG_ENABLE([apparmor],
     [AS_HELP_STRING([--enable-apparmor], [enable apparmor])])
 AS_IF([test "x$enable_apparmor" = "xyes"], [
         HAVE_APPARMOR="-DHAVE_APPARMOR"
         PKG_CHECK_MODULES([AA], [libapparmor],
             [EXTRA_CFLAGS="$EXTRA_CFLAGS $AA_CFLAGS" && EXTRA_LDFLAGS="$EXTRA_LDFLAGS $AA_LIBS"])
-        AC_SUBST([HAVE_APPARMOR])
 ])
 
 HAVE_SELINUX=""
+AC_SUBST([HAVE_SELINUX])
 AC_ARG_ENABLE([selinux],
     [AS_HELP_STRING([--enable-selinux], [SELinux labeling support])])
 AS_IF([test "x$enable_selinux" = "xyes"], [
         HAVE_SELINUX="-DHAVE_SELINUX"
         EXTRA_LDFLAGS="$EXTRA_LDFLAGS -lselinux"
-        AC_SUBST([HAVE_SELINUX])
 ])
 
 AC_SUBST([EXTRA_CFLAGS])
@@ -80,173 +80,171 @@ AC_SUBST([EXTRA_LDFLAGS])
 
 
 HAVE_DBUSPROXY=""
+AC_SUBST([HAVE_DBUSPROXY])
 AC_ARG_ENABLE([dbusproxy],
     [AS_HELP_STRING([--disable-dbusproxy], [disable dbus proxy])])
 AS_IF([test "x$enable_dbusproxy" != "xno"], [
         HAVE_DBUSPROXY="-DHAVE_DBUSPROXY"
-        AC_SUBST([HAVE_DBUSPROXY])
 ])
 
 # overlayfs features temporarily disabled pending fixes
 HAVE_OVERLAYFS=""
 AC_SUBST([HAVE_OVERLAYFS])
-#
 #AC_ARG_ENABLE([overlayfs],
 #    [AS_HELP_STRING([--disable-overlayfs], [disable overlayfs])])
 #AS_IF([test "x$enable_overlayfs" != "xno"], [
 #       HAVE_OVERLAYFS="-DHAVE_OVERLAYFS"
-#       AC_SUBST([HAVE_OVERLAYFS])
 #])
 
 HAVE_OUTPUT=""
+AC_SUBST([HAVE_OUTPUT])
 AC_ARG_ENABLE([output],
     [AS_HELP_STRING([--disable-output], [disable --output logging])])
 AS_IF([test "x$enable_output" != "xno"], [
         HAVE_OUTPUT="-DHAVE_OUTPUT"
-        AC_SUBST([HAVE_OUTPUT])
 ])
 
 HAVE_USERTMPFS=""
+AC_SUBST([HAVE_USERTMPFS])
 AC_ARG_ENABLE([usertmpfs],
     [AS_HELP_STRING([--disable-usertmpfs], [disable tmpfs as regular user])])
 AS_IF([test "x$enable_usertmpfs" != "xno"], [
         HAVE_USERTMPFS="-DHAVE_USERTMPFS"
-        AC_SUBST([HAVE_USERTMPFS])
 ])
 
 HAVE_MAN="no"
+AC_SUBST([HAVE_MAN])
 AC_ARG_ENABLE([man],
     [AS_HELP_STRING([--disable-man], [disable man pages])])
 AS_IF([test "x$enable_man" != "xno"], [
         HAVE_MAN="-DHAVE_MAN"
-        AC_SUBST([HAVE_MAN])
         AC_CHECK_PROG([HAVE_GAWK], [gawk], [yes], [no])
         AS_IF([test "x$HAVE_GAWK" != "xyes"], [AC_MSG_ERROR([*** gawk not found ***])])
 ])
 
 HAVE_FIRETUNNEL=""
+AC_SUBST([HAVE_FIRETUNNEL])
 AC_ARG_ENABLE([firetunnel],
     [AS_HELP_STRING([--disable-firetunnel], [disable firetunnel])])
 AS_IF([test "x$enable_firetunnel" != "xno"], [
         HAVE_FIRETUNNEL="-DHAVE_FIRETUNNEL"
-        AC_SUBST([HAVE_FIRETUNNEL])
 ])
 
 HAVE_PRIVATEHOME=""
+AC_SUBST([HAVE_PRIVATE_HOME])
 AC_ARG_ENABLE([private-home],
     [AS_HELP_STRING([--disable-private-home], [disable private home feature])])
 AS_IF([test "x$enable_private_home" != "xno"], [
         HAVE_PRIVATE_HOME="-DHAVE_PRIVATE_HOME"
-        AC_SUBST([HAVE_PRIVATE_HOME])
 ])
 
 HAVE_CHROOT=""
+AC_SUBST([HAVE_CHROOT])
 AC_ARG_ENABLE([chroot],
     [AS_HELP_STRING([--disable-chroot], [disable chroot])])
 AS_IF([test "x$enable_chroot" != "xno"], [
         HAVE_CHROOT="-DHAVE_CHROOT"
-        AC_SUBST([HAVE_CHROOT])
 ])
 
 HAVE_GLOBALCFG=""
+AC_SUBST([HAVE_GLOBALCFG])
 AC_ARG_ENABLE([globalcfg],
     [AS_HELP_STRING([--disable-globalcfg],
         [if the global config file firejail.cfg is not present, continue the program using defaults])])
 AS_IF([test "x$enable_globalcfg" != "xno"], [
         HAVE_GLOBALCFG="-DHAVE_GLOBALCFG"
-        AC_SUBST([HAVE_GLOBALCFG])
 ])
 
 HAVE_NETWORK=""
+AC_SUBST([HAVE_NETWORK])
 AC_ARG_ENABLE([network],
     [AS_HELP_STRING([--disable-network], [disable network])])
 AS_IF([test "x$enable_network" != "xno"], [
         HAVE_NETWORK="-DHAVE_NETWORK"
-        AC_SUBST([HAVE_NETWORK])
 ])
 
 HAVE_USERNS=""
+AC_SUBST([HAVE_USERNS])
 AC_ARG_ENABLE([userns],
     [AS_HELP_STRING([--disable-userns], [disable user namespace])])
 AS_IF([test "x$enable_userns" != "xno"], [
         HAVE_USERNS="-DHAVE_USERNS"
-        AC_SUBST([HAVE_USERNS])
 ])
 
 HAVE_X11=""
+AC_SUBST([HAVE_X11])
 AC_ARG_ENABLE([x11],
     [AS_HELP_STRING([--disable-x11], [disable X11 sandboxing support])])
 AS_IF([test "x$enable_x11" != "xno"], [
         HAVE_X11="-DHAVE_X11"
-        AC_SUBST([HAVE_X11])
 ])
 
 HAVE_FILE_TRANSFER=""
+AC_SUBST([HAVE_FILE_TRANSFER])
 AC_ARG_ENABLE([file-transfer],
     [AS_HELP_STRING([--disable-file-transfer], [disable file transfer])])
 AS_IF([test "x$enable_file_transfer" != "xno"], [
         HAVE_FILE_TRANSFER="-DHAVE_FILE_TRANSFER"
-        AC_SUBST([HAVE_FILE_TRANSFER])
 ])
 
 HAVE_SUID=""
+AC_SUBST([HAVE_SUID])
 AC_ARG_ENABLE([suid],
     [AS_HELP_STRING([--disable-suid], [install as a non-SUID executable])])
 AS_IF([test "x$enable_suid" = "xno"],
         [HAVE_SUID="no"],
         [HAVE_SUID="yes"]
 )
-AC_SUBST([HAVE_SUID])
 
 HAVE_FATAL_WARNINGS=""
+AC_SUBST([HAVE_FATAL_WARNINGS])
 AC_ARG_ENABLE([fatal_warnings],
     [AS_HELP_STRING([--enable-fatal-warnings], [-W -Wall -Werror])])
 AS_IF([test "x$enable_fatal_warnings" = "xyes"], [
         HAVE_FATAL_WARNINGS="-W -Wall -Werror"
-        AC_SUBST([HAVE_FATAL_WARNINGS])
 ])
 
 BUSYBOX_WORKAROUND="no"
+AC_SUBST([BUSYBOX_WORKAROUND])
 AC_ARG_ENABLE([busybox-workaround],
     [AS_HELP_STRING([--enable-busybox-workaround], [enable busybox workaround])])
 AS_IF([test "x$enable_busybox_workaround" = "xyes"], [
         BUSYBOX_WORKAROUND="yes"
-        AC_SUBST([BUSYBOX_WORKAROUND])
 ])
 
 
 HAVE_GCOV=""
+AC_SUBST([HAVE_GCOV])
 AC_ARG_ENABLE([gcov],
     [AS_HELP_STRING([--enable-gcov], [Gcov instrumentation])])
 AS_IF([test "x$enable_gcov" = "xyes"], [
         HAVE_GCOV="--coverage -DHAVE_GCOV"
         EXTRA_LDFLAGS="$EXTRA_LDFLAGS -lgcov --coverage"
-        AC_SUBST([HAVE_GCOV])
 ])
 
 HAVE_CONTRIB_INSTALL="yes"
+AC_SUBST([HAVE_CONTRIB_INSTALL])
 AC_ARG_ENABLE([contrib-install],
     [AS_HELP_STRING([--enable-contrib-install], [install contrib scripts])])
 AS_IF([test "x$enable_contrib_install" = "xno"],
         [HAVE_CONTRIB_INSTALL="no"],
         [HAVE_CONTRIB_INSTALL="yes"]
 )
-AC_SUBST([HAVE_CONTRIB_INSTALL])
 
 HAVE_FORCE_NONEWPRIVS=""
+AC_SUBST([HAVE_FORCE_NONEWPRIVS])
 AC_ARG_ENABLE([force-nonewprivs],
     [AS_HELP_STRING([--enable-force-nonewprivs], [enable force nonewprivs])])
 AS_IF([test "x$enable_force_nonewprivs" = "xyes"], [
         HAVE_FORCE_NONEWPRIVS="-DHAVE_FORCE_NONEWPRIVS"
-        AC_SUBST([HAVE_FORCE_NONEWPRIVS])
 ])
 
 HAVE_LTS=""
+AC_SUBST([HAVE_LTS])
 AC_ARG_ENABLE([lts],
     [AS_HELP_STRING([--enable-lts], [enable long-term support software version (LTS)])])
 AS_IF([test "x$enable_lts" = "xyes"], [
         HAVE_LTS="-DHAVE_LTS"
-        AC_SUBST([HAVE_LTS])
 
         HAVE_DBUSPROXY=""
         AC_SUBST([HAVE_DBUSPROXY])