Add $EUDEV_RULES_DIRECTORY to the list of rules directories.

The old udev 182 supported $UDEV_CONFIG_FILE, which in turn allowed
the search path to be customized, but eudev no longer has this, hence
this hack.

--- eudev-3.1.5/src/udev/udev-rules.c	2015-10-13 06:22:14.000000000 +0800
+++ eudev-3.1.5/src/udev/udev-rules.c	2015-10-16 20:45:38.491934336 +0800
@@ -47,15 +47,11 @@
         };
 };
 
-static const char* const rules_dirs[] = {
+static const char* rules_dirs[] = {
         UDEV_CONF_DIR "/rules.d",
         UDEV_RULES_DIR,
-        UDEV_ROOT_RUN "/udev/rules.d",
         UDEV_LIBEXEC_DIR "/rules.d",
-#ifdef HAVE_SPLIT_USR
-        "/lib/udev/rules.d",
-        "/usr/lib/udev/rules.d",
-#endif
+        NULL,			/* placeholder for $EUDEV_RULES_DIRECTORY */
         NULL};
 
 struct udev_rules {
@@ -1704,6 +1700,9 @@
 
         udev_rules_check_timestamp(rules);
 
+        /* Allow the user to specify an additional rules directory.  */
+        rules_dirs[3] = getenv("EUDEV_RULES_DIRECTORY");
+
         r = conf_files_list_strv(&files, ".rules", NULL, rules_dirs);
         if (r < 0) {
                 log_error_errno(r, "failed to enumerate rules files: %m");
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<div class='path'>path: <a href='/guix/log/?id=de96ed11efdfb450ca45952aceda656a78d981c4'>root</a>/<a href='/guix/log/gnu?id=de96ed11efdfb450ca45952aceda656a78d981c4'>gnu</a>/<a href='/guix/log/gnu/installer?id=de96ed11efdfb450ca45952aceda656a78d981c4'>installer</a>/<a href='/guix/log/gnu/installer/newt?id=de96ed11efdfb450ca45952aceda656a78d981c4'>newt</a>/<a href='/guix/log/gnu/installer/newt/ethernet.scm?id=de96ed11efdfb450ca45952aceda656a78d981c4'>ethernet.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/installer/newt/ethernet.scm?id=de96ed11efdfb450ca45952aceda656a78d981c4&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2019-05-06 23:21:33 +0200'>2019-05-06</span></td><td><a href='/guix/commit/gnu/installer/newt/ethernet.scm?id=46c102ca5e76ffc1daa42edba439eee9fd0f102c'>installer: Skip network selection dialogs when there is no choice.</a><span class='msg-avail'>...<span class='msg-tooltip'>Previously, for a machine that only has wired networking, and only one
such network, we'd have to go through two selection boxes.  Now we just
skip both.

* gnu/installer/newt/ethernet.scm (run-ethernet-page): When
'ethernet-services' returns one element, return it directly without
opening a listbox selection.
* gnu/installer/newt/network.scm (run-technology-page): Likewise.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-05-06 23:21:33 +0200'>2019-05-06</span></td><td><a href='/guix/commit/gnu/installer/newt/ethernet.scm?id=d1e5f758e128a3c1042c98563c5b87b81b2f187a'>installer: Shrink simple listboxes to their minimum height.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/installer/newt/partition.scm (run-partioning-page): Pass
 #:listbox-height.
(run-scheme-page): Likewise.
(run-device-page): Likewise.
* gnu/installer/newt/network.scm (run-technology-page): Likewise.
* gnu/installer/newt/ethernet.scm (run-ethernet-page): Likewise.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-01-17 14:04:25 +0100'>2019-01-17</span></td><td><a href='/guix/commit/gnu/installer/newt/ethernet.scm?id=7d812901daf0259d5d381199168d6d2994ce00ac'>installer: Turn "Cancel" buttons into "Exit" buttons.</a><span class='msg-avail'>...<span class='msg-tooltip'>This change and previous ones were,
Suggested-by: Thorsten Wilms &lt;t_w_@freenet.de&gt;
here: https://lists.gnu.org/archive/html/guix-devel/2018-11/msg00330.html

gnu/installer/newt/ethernet.scm: Turn cancel into exit.
gnu/installer/newt/final.scm: Ditto.
gnu/installer/newt/keymap.scm: Ditto.
gnu/installer/newt/locale.scm: Ditto.
gnu/installer/newt/network.scm: Ditto.
gnu/installer/newt/page.scm: Ditto.
gnu/installer/newt/partition.scm: Ditto.
gnu/installer/newt/services.scm: Ditto.
gnu/installer/newt/timezone.scm: Ditto.
gnu/installer/newt/user.scm: Ditto.
gnu/installer/newt/wifi.scm: Ditto.
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2019-01-17 14:04:23 +0100'>2019-01-17</span></td><td><a href='/guix/commit/gnu/installer/newt/ethernet.scm?id=fb1675cbca68a7ada710640294a26cf0f1b22168'>installer: Fix ethernet connection.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/installer/newt/ethernet.scm (connect-ethernet-service): Return the
service passed as parameter.
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2019-01-17 14:04:20 +0100'>2019-01-17</span></td><td><a href='/guix/commit/gnu/installer/newt/ethernet.scm?id=d0f3a672dcbdfefd3556b6a21985ff0e35eed3be'>gnu: Add graphical installer support.</a><span class='msg-avail'>...<span class='msg-tooltip'>* configure.ac: Require that guile-newt is available.
* gnu/installer.scm: New file.
* gnu/installer/aux-files/logo.txt: New file.
* gnu/installer/build-installer.scm: New file.
* gnu/installer/connman.scm: New file.
* gnu/installer/keymap.scm: New file.
* gnu/installer/locale.scm: New file.
* gnu/installer/newt.scm: New file.
* gnu/installer/newt/ethernet.scm: New file.
* gnu/installer/newt/hostname.scm: New file.
* gnu/installer/newt/keymap.scm: New file.
* gnu/installer/newt/locale.scm: New file.
* gnu/installer/newt/menu.scm: New file.
* gnu/installer/newt/network.scm: New file.
* gnu/installer/newt/page.scm: New file.
* gnu/installer/newt/timezone.scm: New file.
* gnu/installer/newt/user.scm: New file.
* gnu/installer/newt/utils.scm: New file.
* gnu/installer/newt/welcome.scm: New file.
* gnu/installer/newt/wifi.scm: New file.
* gnu/installer/steps.scm: New file.
* gnu/installer/timezone.scm: New file.
* gnu/installer/utils.scm: New file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add previous files.
* gnu/system.scm: Export %root-account.
* gnu/system/install.scm (%installation-services): Use kmscon instead of linux
VT for all tty.
(installation-os)[users]: Add the graphical installer as shell of the root
account.
[packages]: Add font related packages.
* po/guix/POTFILES.in: Add installer files.
</span></span></td><td>Mathieu Othacehe</td></tr>