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='2020-11-07 13:40:46 +0100'>2020-11-07</span></td><td><a href='/guix/commit/gnu/system/uuid.scm?id=e87471dc510bc393e3306fba86f919dc6bf89b7b'>uuid: Add support for bcachefs.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-07-26 18:35:10 +0200'>2020-07-26</span></td><td><a href='/guix/commit/gnu/system/uuid.scm?id=675e56221e3dfc58cac94bf30835f16a9c41d530'>file-systems: Add NTFS support.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-06-18 23:24:37 -0400'>2020-06-18</span></td><td><a href='/guix/commit/gnu/system/uuid.scm?id=04a4af6dd4fbfcfc564eac5eafe647b192ba3a8f'>uuid: Prevent a loop on invalid arguments.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2020-01-03 13:54:13 +0100'>2020-01-03</span></td><td><a href='/guix/commit/gnu/system/uuid.scm?id=43c4d27cdfed5ce98ecd4ce48fcd43e188e5a3aa'>uuid: Add support for JFS.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2019-05-07 12:18:44 +0200'>2019-05-07</span></td><td><a href='/guix/commit/gnu/system/uuid.scm?id=6c5790a2faf8ffc401e43b13425a707394e40874'>uuid: 'fat-uuid-&gt;string' preserves leading zeros.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
taller-log-line everywhere.</a><span class='msg-avail'>...</span></td><td>Josselin Poiret</td></tr>
<tr><td><span title='2022-01-14 14:29:19 +0100'>2022-01-14</span></td><td><a href='/guix/commit/gnu/installer/final.scm?id=e92723452d2f1e7639579ea327d3fff6fa25ef4c'>installer: Install the locale before mounting the cow-store.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2022-01-14 14:29:15 +0100'>2022-01-14</span></td><td><a href='/guix/commit/gnu/installer/final.scm?id=0c9693d8b3f9ecd40732ec86b732bbf99f8e8b4d'>installer: Do not set the locale in run-command.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2022-01-14 14:29:12 +0100'>2022-01-14</span></td><td><a href='/guix/commit/gnu/installer/final.scm?id=7c923e6cf4412db3ef22792d639b98f8fbf7f037'>installer: Remove an unused procedure.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-09-10 09:38:52 +0200'>2020-09-10</span></td><td><a href='/guix/commit/gnu/installer/final.scm?id=cafbc5f39084cff62879206d69a3890fce54dc27'>installer: final: Introduce call-with-mnt-container.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-09-02 17:05:23 +0200'>2020-09-02</span></td><td><a href='/guix/commit/gnu/installer/final.scm?id=8ce6f4dc2879919c12bc76a2f4b01200af97e019'>installer: Run the installation inside a container.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-06-16 16:33:55 +0200'>2020-06-16</span></td><td><a href='/guix/commit/gnu/installer/final.scm?id=4febc38d9f398a44e2f72eb6fa71145421c117a3'>installer: final: Remove restart-service procedure.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-06-13 15:21:20 +0200'>2020-06-13</span></td><td><a href='/guix/commit/gnu/installer/final.scm?id=478d1270ce4029b7fe5bfbb369f8e35c57b32ab2'>install: final: Add some logging.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-06-09 17:59:05 +0200'>2020-06-09</span></td><td><a href='/guix/commit/gnu/installer/final.scm?id=9392652e911b3963ef0f52f39677a6fc953f1e1e'>installer: final: Dump "guix system init" command output when testing.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-06-09 17:59:05 +0200'>2020-06-09</span></td><td><a href='/guix/commit/gnu/installer/final.scm?id=ce16b07d10ebda486d6e4cb6fd30fe797125aeac'>installer: final: Remove left-over pk call.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-06-05 09:04:23 +0200'>2020-06-05</span></td><td><a href='/guix/commit/gnu/installer/final.scm?id=7730f41afd90a9c3c83a56adfee09069da66a8e5'>installer: final: Add some extra logging.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>