libudev: queue - always rebuild queue file when nothing is queued anymore

[elogind.git] / libudev / libudev-queue-private.c

diff --git a/libudev/libudev-queue-private.c b/libudev/libudev-queue-private.c
index a799be062a961aa8829d97133456b5910dacc4ad..0dcf9b00204cb2c1877f0107edadff51a5c6e1ec 100644 (file)
--- a/libudev/libudev-queue-private.c
+++ b/libudev/libudev-queue-private.c
@@ -164,7 +164,7 @@ static struct queue_devpaths *build_index(struct udev_queue_export *udev_queue_e
        devpaths->devpaths_size = range + 1;
 
        /* read all records and populate the table */
-       while(1) {
+       for (;;) {
                if (udev_queue_read_seqnum(udev_queue_export->queue_file, &seqnum) < 0)
                        break;
                n = seqnum - udev_queue_export->seqnum_max;
@@ -303,8 +303,10 @@ static int write_queue_record(struct udev_queue_export *udev_queue_export,
        len = (devpath_len < USHRT_MAX) ? devpath_len : USHRT_MAX;
        if (fwrite(&len, sizeof(unsigned short), 1, udev_queue_export->queue_file) != 1)
                goto write_error;
-       if (fwrite(devpath, 1, len, udev_queue_export->queue_file) != len)
-               goto write_error;
+       if (len > 0) {
+               if (fwrite(devpath, 1, len, udev_queue_export->queue_file) != len)
+                       goto write_error;
+       }
 
        /* *must* flush output; caller may fork */
        if (fflush(udev_queue_export->queue_file) != 0)
@@ -342,6 +344,7 @@ static int update_queue(struct udev_queue_export *udev_queue_export,
        int bytes;
        int err;
 
+       /* FINISHED records have a zero length devpath */
        if (state == DEVICE_QUEUED) {
                devpath = udev_device_get_devpath(udev_device);
                devpath_len = strlen(devpath);
@@ -353,12 +356,9 @@ static int update_queue(struct udev_queue_export *udev_queue_export,
                        return -1;
        }
 
-       /* when the queue file grows too large, garbage-collect and rebuild it */
-       bytes = ftell(udev_queue_export->queue_file) + queue_record_size(devpath_len);
-
        /* if we're removing the last event from the queue, that's the best time to rebuild it */
-       if (state != DEVICE_QUEUED && udev_queue_export->queued_count == 1 && bytes > 2048) {
-               /* because we don't need to read the old queue file */
+       if (state != DEVICE_QUEUED && udev_queue_export->queued_count == 1) {
+               /* we don't need to read the old queue file */
                fclose(udev_queue_export->queue_file);
                udev_queue_export->queue_file = NULL;
                rebuild_queue_file(udev_queue_export);
@@ -366,6 +366,7 @@ static int update_queue(struct udev_queue_export *udev_queue_export,
        }
 
        /* try to rebuild the queue files before they grow larger than one page. */
+       bytes = ftell(udev_queue_export->queue_file) + queue_record_size(devpath_len);
        if ((udev_queue_export->waste_bytes > bytes / 2) && bytes > 4096)
                rebuild_queue_file(udev_queue_export);