chiark / gitweb /
udevd: export event queue and event state
authorKay Sievers <kay.sievers@suse.de>
Wed, 16 Nov 2005 03:12:53 +0000 (04:12 +0100)
committerKay Sievers <kay.sievers@suse.de>
Wed, 16 Nov 2005 03:12:53 +0000 (04:12 +0100)
All pending and running events can be found as symlinks to the actual
device in /dev/.udev/queue/ now. This way we can lookup if specific events
are still in the queue, before doing actions which require events to have
finished.

All failed event processes can be found in /dev/.udev/failed/. This makes
it possible to retry a failed event process at a later time in the boot
process.

Signed-off-by: Kay Sievers <kay.sievers@suse.de>
udevd.c

diff --git a/udevd.c b/udevd.c
index b7b3061..93f02c5 100644 (file)
--- a/udevd.c
+++ b/udevd.c
@@ -133,9 +133,83 @@ static int udev_event_process(struct uevent_msg *msg)
        return retval;
 }
 
+enum event_state {
+       EVENT_QUEUED,
+       EVENT_FINISHED,
+       EVENT_FAILED,
+};
+
+#define PATH_TO_NAME_CHAR              '@'
+#define EVENT_QUEUE_DIR                        ".udev/queue"
+#define EVENT_FAILED_DIR               ".udev/failed"
+static void export_event_state(struct uevent_msg *msg, enum event_state state)
+{
+       char filename[PATH_SIZE];
+       char filename_failed[PATH_SIZE];
+       char target[PATH_SIZE];
+       size_t start, end, i;
+       struct uevent_msg *loop_msg;
+
+       /* add location of queue files */
+       strlcpy(filename, udev_root, sizeof(filename));
+       strlcat(filename, "/", sizeof(filename));
+       start = strlcat(filename, EVENT_QUEUE_DIR, sizeof(filename));
+       end = strlcat(filename, msg->devpath, sizeof(filename));
+       if (end > sizeof(filename))
+               end = sizeof(filename);
+
+       /* replace '/' to transform path into a filename */
+       for (i = start+1; i < end; i++)
+               if (filename[i] == '/')
+                       filename[i] = PATH_TO_NAME_CHAR;
+
+       /* add location of failed files */
+       strlcpy(filename_failed, udev_root, sizeof(filename_failed));
+       strlcat(filename_failed, "/", sizeof(filename_failed));
+       start = strlcat(filename_failed, EVENT_FAILED_DIR, sizeof(filename_failed));
+       end = strlcat(filename_failed, msg->devpath, sizeof(filename_failed));
+       if (end > sizeof(filename_failed))
+               end = sizeof(filename_failed);
+
+       /* replace '/' to transform path into a filename */
+       for (i = start+1; i < end; i++)
+               if (filename_failed[i] == '/')
+                       filename_failed[i] = PATH_TO_NAME_CHAR;
+
+       switch (state) {
+       case EVENT_QUEUED:
+               unlink(filename_failed);
+
+               strlcpy(target, sysfs_path, sizeof(target));
+               strlcat(target, msg->devpath, sizeof(target));
+               create_path(filename);
+               symlink(target, filename);
+               return;
+       case EVENT_FINISHED:
+               unlink(filename_failed);
+
+               /* don't remove if events for the same path are still pending */
+               list_for_each_entry(loop_msg, &running_list, node)
+                       if (loop_msg->devpath && strcmp(loop_msg->devpath, msg->devpath) == 0)
+                               return;
+               unlink(filename);
+       case EVENT_FAILED:
+               create_path(filename_failed);
+               rename(filename, filename_failed);
+               return;
+       }
+}
+
 static void msg_queue_delete(struct uevent_msg *msg)
 {
        list_del(&msg->node);
+
+       /* mark as failed, if add event returns non-zero */
+       if (msg->exitstatus && strcmp(msg->action, "add") == 0)
+               export_event_state(msg, EVENT_FAILED);
+       else
+               export_event_state(msg, EVENT_FINISHED);
+
        free(msg);
 }
 
@@ -181,6 +255,8 @@ static void msg_queue_insert(struct uevent_msg *msg)
 {
        msg->queue_time = time(NULL);
 
+       export_event_state(msg, EVENT_QUEUED);
+
        /* run all events with a timeout set immediately */
        if (msg->timeout != 0) {
                list_add_tail(&msg->node, &running_list);