From 7a7702509259f811d4f8321e64e28dc72037c88b Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Wed, 16 Nov 2005 04:12:53 +0100 Subject: [PATCH] udevd: export event queue and event state 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 --- udevd.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) diff --git a/udevd.c b/udevd.c index b7b306131..93f02c539 100644 --- 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); -- 2.30.2