dbus: add notification from commands

When a command modifies a PV or VG, or changes the
activation state of an LV, it will send a dbus
notification when the command is finished.  This
can be enabled/disabled with a config setting.

2 files changed, 129 insertions, 0 deletions

diff --git a/lib/notify/lvmnotify.c b/lib/notify/lvmnotify.c
new file mode 100644
index 000000000..0b04ee4ba
--- /dev/null
+++ b/lib/notify/lvmnotify.c
@@ -0,0 +1,109 @@
+/*
+ * Copyright (C) 2015 Red Hat, Inc.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ */
+
+#include "lib.h"
+#include "toolcontext.h"
+#include "metadata.h"
+#include "lvmnotify.h"
+
+#define LVM_DBUS_DESTINATION "com.redhat.lvmdbus1"
+#define LVM_DBUS_PATH        "/com/redhat/lvmdbus1/Manager"
+#define LVM_DBUS_INTERFACE   "com.redhat.lvmdbus1.Manager"
+
+#ifdef NOTIFYDBUS_SUPPORT
+#include <systemd/sd-bus.h>
+
+void lvmnotify_send(struct cmd_context *cmd)
+{
+	sd_bus *bus = NULL;
+	sd_bus_message *m = NULL;
+	sd_bus_error error = SD_BUS_ERROR_NULL;
+	const char *cmd_name;
+	int ret;
+	int result = 0;
+
+	if (!cmd->vg_notify && !cmd->lv_notify && !cmd->pv_notify)
+		return;
+
+	cmd->vg_notify = 0;
+	cmd->lv_notify = 0;
+	cmd->pv_notify = 0;
+
+	cmd_name = get_cmd_name();
+
+	ret = sd_bus_open_system(&bus);
+	if (ret < 0) {
+		log_debug_dbus("Failed to connect to dbus: %d", ret);
+		return;
+	}
+
+	log_debug_dbus("Nofify dbus at %s.", LVM_DBUS_DESTINATION);
+
+	ret = sd_bus_call_method(bus,
+				 LVM_DBUS_DESTINATION,
+				 LVM_DBUS_PATH,
+				 LVM_DBUS_INTERFACE,
+				 "ExternalEvent",
+				 &error,
+				 &m,
+				 "s",
+				 cmd_name);
+
+	if (ret < 0) {
+		log_warn("WARNING: D-Bus notification failed: %s", error.message);
+		goto out;
+	}
+
+	ret = sd_bus_message_read(m, "i", &result);
+	if (ret < 0)
+		log_debug_dbus("Failed to parse dbus response message: %d", ret);
+	if (result)
+		log_debug_dbus("Bad return value from dbus service: %d", result);
+out:
+	sd_bus_error_free(&error);
+	sd_bus_message_unref(m);
+	sd_bus_unref(bus);
+}
+
+void set_vg_notify(struct cmd_context *cmd)
+{
+	cmd->vg_notify = 1;
+}
+
+void set_lv_notify(struct cmd_context *cmd)
+{
+	cmd->lv_notify = 1;
+}
+
+void set_pv_notify(struct cmd_context *cmd)
+{
+	cmd->pv_notify = 1;
+}
+
+#else
+
+void lvmnotify_send(struct cmd_context *cmd)
+{
+}
+
+void set_vg_notify(struct cmd_context *cmd)
+{
+}
+
+void set_lv_notify(struct cmd_context *cmd)
+{
+}
+
+void set_pv_notify(struct cmd_context *cmd)
+{
+}
+
+#endif
+
diff --git a/lib/notify/lvmnotify.h b/lib/notify/lvmnotify.h
new file mode 100644
index 000000000..43fffd0da
--- /dev/null
+++ b/lib/notify/lvmnotify.h
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2015 Red Hat, Inc.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ */
+
+#ifndef _LVMNOTIFY_H
+#define _LVMNOTIFY_H
+
+void lvmnotify_send(struct cmd_context *cmd);
+void set_vg_notify(struct cmd_context *cmd);
+void set_lv_notify(struct cmd_context *cmd);
+void set_pv_notify(struct cmd_context *cmd);
+
+#endif
+