Revert "sd-bus: do not connect to dbus-1 socket when kdbus is available"

This reverts commit d4d00020d6ad855d65d31020fefa5003e1bb477f. The idea of
the commit is broken and needs to be reworked. We really cannot reduce
the bus-addresses to a single address. We always will have systemd with
native clients and legacy clients at the same time, so we also need both
addresses at the same time.

1 files changed, 34 insertions, 0 deletions

diff --git a/src/shared/bus-util.c b/src/shared/bus-util.c
index 1bcb8903f3..1369a61458 100644
--- a/src/shared/bus-util.c
+++ b/src/shared/bus-util.c
@@ -2032,3 +2032,37 @@ int bus_path_decode_unique(const char *path, const char *prefix, char **ret_send
         *ret_external = external;
         return 1;
 }
+
+bool is_kdbus_wanted(void) {
+        _cleanup_free_ char *value = NULL;
+#ifdef ENABLE_KDBUS
+        const bool configured = true;
+#else
+        const bool configured = false;
+#endif
+
+        int r;
+
+        if (get_proc_cmdline_key("kdbus", NULL) > 0)
+                return true;
+
+        r = get_proc_cmdline_key("kdbus=", &value);
+        if (r <= 0)
+                return configured;
+
+        return parse_boolean(value) == 1;
+}
+
+bool is_kdbus_available(void) {
+        _cleanup_close_ int fd = -1;
+        struct kdbus_cmd cmd = { .size = sizeof(cmd), .flags = KDBUS_FLAG_NEGOTIATE };
+
+        if (!is_kdbus_wanted())
+                return false;
+
+        fd = open("/sys/fs/kdbus/control", O_RDWR | O_CLOEXEC | O_NONBLOCK | O_NOCTTY);
+        if (fd < 0)
+                return false;
+
+        return ioctl(fd, KDBUS_CMD_BUS_MAKE, &cmd) >= 0;
+}