Allow the configuration file to be specified via an environment variable.

diff --git a/src/gclue-config.c b/src/gclue-config.c
index 7ab2a67..e41f3df 100644
--- a/src/gclue-config.c
+++ b/src/gclue-config.c
@@ -332,6 +332,11 @@ static void
 gclue_config_init (GClueConfig *config)
 {
         GError *error = NULL;
+	const char *config_file_path;
+
+	config_file_path = g_getenv ("GEOCLUE_CONFIG_FILE");
+	if (!config_file_path)
+            config_file_path = CONFIG_FILE_PATH;
 
         config->priv = gclue_config_get_instance_private(config);
         config->priv->key_file = g_key_file_new ();
@@ -341,7 +346,7 @@ gclue_config_init (GClueConfig *config)
                                    &error);
         if (error != NULL) {
                 g_critical ("Failed to load configuration file '%s': %s",
-                            CONFIG_FILE_PATH, error->message);
+                            config_file_path, error->message);
                 g_error_free (error);
 
                 return;
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<tr><td><span title='2023-05-21 01:04:39 +0200'>2023-05-21</span></td><td><a href='/guix/commit/gnu/system/pam.scm?id=f52020ea99f59eae3537a22bb23305da90af310b'>system: pam: Change 'stop' method to return #f.</a><span class='msg-avail'>...<span class='msg-tooltip'>When the 'stop' method returns a truth value, shepherd interprets it as
potential failure and logs it.

* gnu/system/pam.scm (pam-shepherd-service): Change 'stop' method to
return #f.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-05-11 13:21:45 +0200'>2023-05-11</span></td><td><a href='/guix/commit/gnu/system/pam.scm?id=2df5d4fd18a2fbcb8066a50e2da8ec64635f5162'>system: pam: Let PAM extensions add shepherd requirements.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/system/pam.scm (&lt;pam-extension&gt;): New record type.
(pam-shepherd-service): Add Shepherd synchronization point.

* gnu/services/mail.scm (dovecot-shepherd-service)
* gnu/services/lightdm.scm (lightdm-shepherd-service)
* gnu/services/mail.scm (opensmtpd-shepherd-service)
* gnu/services/sddm.scm (sddm-shepherd-service)
* gnu/services/ssh.scm (lsh-shepherd-service, openssh-shepherd-service)
* gnu/services/xorg.scm (slim-shepherd-service, gdm-shepherd-service)
* gnu/services/base.scm (greetd-shepherd-services): Add PAM requirement.

* gnu/system/pam.scm (/etc-entry, extend-configuration,
pam-root-service-type, pam-root-service)
* gnu/services/authentication.scm (pam-ldap-pam-service)
* gnu/services/base.scm (pam-limits-service-type)
(greetd-pam-service)
* gnu/services/desktop.scm (pam-gnome-keyring)
* gnu/services/kerberos.scm (pam-krb5-pam-service)
* gnu/services/pam-mount.scm (pam-mount-pam-service): Adapt to use
pam-extension.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Josselin Poiret</td></tr>