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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<tr><td><span title='2023-10-22 16:09:04 -0400'>2023-10-22</span></td><td><a href='/guix/commit/.patman?id=f44fa21c3ec1d9bf1b9da009e1c795942bf654eb'>gnu: patman: Apply patch for new Change-Id setting.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/bootloaders.scm (u-boot) [source]: Apply patch.
* gnu/packages/patches/u-boot-patman-change-id.patch: New file.
* gnu/local.mk (dist_patch_DATA): Register it.
* .patman (keep_change_id): Use it.

Series-changes: 3
 - New commit
Change-Id: I33c03013f6a260b5f5d80212b7b6ebe8a3f97efa
</span></span></td><td>Maxim Cournoyer</td></tr>