Merge pull request #5175 from keszybz/hostname-fallback

Allow distributions to override the "localhost" fallback

configure.ac

@@ -601,6 +601,15 @@ AC_ARG_WITH([nobody-group],
 AC_SUBST(NOBODY_GROUP_NAME)
 AC_DEFINE_UNQUOTED(NOBODY_GROUP_NAME, ["$NOBODY_GROUP_NAME"], [The name of the nobody group (the one with GID 65534)])
 
+AC_ARG_WITH([fallback-hostname],
+        AS_HELP_STRING([--with-fallback-hostname=NAME],
+                [specify the hostname used if none configured]),
+        [FALLBACK_HOSTNAME="$withval"],
+        [FALLBACK_HOSTNAME=localhost])
+
+AC_SUBST(FALLBACK_HOSTNAME)
+AC_DEFINE_UNQUOTED(FALLBACK_HOSTNAME, ["$FALLBACK_HOSTNAME"], [The hostname used if none configured])
+
 # ------------------------------------------------------------------------------
 have_xz=no
 AC_ARG_ENABLE(xz, AS_HELP_STRING([--disable-xz], [disable optional XZ support]))
@@ -1715,12 +1724,13 @@ AC_MSG_RESULT([
         Wheel group:                       ${have_wheel_group}
         Debug shell:                       ${SUSHELL} @ ${DEBUGTTY}
         TTY GID:                           ${TTY_GID}
-        Maximum System UID:                ${SYSTEM_UID_MAX}
-        Maximum System GID:                ${SYSTEM_GID_MAX}
+        Maximum system UID:                ${SYSTEM_UID_MAX}
+        Maximum system GID:                ${SYSTEM_GID_MAX}
         Certificate root:                  ${CERTIFICATEROOT}
         Support URL:                       ${SUPPORT_URL}
-        Nobody User Name:                  ${NOBODY_USER_NAME}
-        Nobody Group Name:                 ${NOBODY_GROUP_NAME}
+        nobody user name:                  ${NOBODY_USER_NAME}
+        nobody group name:                 ${NOBODY_GROUP_NAME}
+        Fallback hostname:                 ${FALLBACK_HOSTNAME}
 
         CFLAGS:   ${OUR_CFLAGS} ${CFLAGS}
         CPPFLAGS: ${OUR_CPPFLAGS} ${CPPFLAGS}

src/hostname/hostnamed.c

@@ -283,7 +283,7 @@ static int context_update_kernel_hostname(Context *c) {
 
         /* ... and the ultimate fallback */
         else
-                hn = "localhost";
+                hn = FALLBACK_HOSTNAME;
 
         if (sethostname_idempotent(hn) < 0)
                 return -errno;
@@ -419,7 +419,7 @@ static int method_set_hostname(sd_bus_message *m, void *userdata, sd_bus_error *
                 name = c->data[PROP_STATIC_HOSTNAME];
 
         if (isempty(name))
-                name = "localhost";
+                name = FALLBACK_HOSTNAME;
 
         if (!hostname_is_valid(name, false))
                 return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid hostname '%s'", name);