smbd: implement the strange write time update logic

[kai/samba-autobuild/.git] / source3 / smbd / fileio.c

diff --git a/source3/smbd/fileio.c b/source3/smbd/fileio.c
index 8cea4989f5b4dd16f5d3ad26208e951094a1e908..93a303f6c867e232d64508a2c7d8020d9ca1c3d6 100644 (file)
--- a/source3/smbd/fileio.c
+++ b/source3/smbd/fileio.c
@@ -142,27 +142,6 @@ static ssize_t real_write_file(struct smb_request *req,
        if (ret != -1) {
                fsp->fh->pos += ret;
 
-               /*
-                * It turns out that setting the last write time from a Windows
-                * client stops any subsequent writes from updating the write time.
-                * Doing this after the write gives a race condition here where
-                * a stat may see the changed write time before we reset it here,
-                * but it's cheaper than having to store the write time in shared
-                * memory and look it up using dev/inode across all running smbd's.
-                * The 99% solution will hopefully be good enough in this case. JRA.
-                */
-
-               if (!null_timespec(fsp->pending_modtime)) {
-                       set_filetime(fsp->conn, fsp->fsp_name,
-                                       fsp->pending_modtime);
-
-                       /* If we didn't get the "set modtime" call ourselves, we must
-                          store the last write time to restore on close. JRA. */
-                       if (!fsp->pending_modtime_owner) {
-                               fsp->last_write_time = timespec_current();
-                       }
-               }
-
 /* Yes - this is correct - writes don't update this. JRA. */
 /* Found by Samba4 tests. */
 #if 0
@@ -192,6 +171,41 @@ static int wcp_file_size_change(files_struct *fsp)
        return ret;
 }
 
+static void update_write_time_handler(struct event_context *ctx,
+                                     struct timed_event *te,
+                                     const struct timeval *now,
+                                     void *private_data)
+{
+       files_struct *fsp = (files_struct *)private_data;
+
+       /* Remove the timed event handler. */
+       TALLOC_FREE(fsp->update_write_time_event);
+       DEBUG(5, ("Update write time on %s\n", fsp->fsp_name));
+
+       /* change the write time if not already changed by someoneelse */
+       set_write_time_fsp(fsp, timespec_current(), false);
+}
+
+void trigger_write_time_update(struct files_struct *fsp)
+{
+       if (fsp->write_time_forced) {
+               return;
+       }
+
+       if (fsp->update_write_time_triggered) {
+               return;
+       }
+       fsp->update_write_time_triggered = true;
+
+       /* trigger the update 2 seconds later */
+       fsp->update_write_time_on_close = true;
+       fsp->update_write_time_event =
+               event_add_timed(smbd_event_context(), NULL,
+                               timeval_current_ofs(2, 0),
+                               "update_write_time_handler",
+                               update_write_time_handler, fsp);
+}
+
 /****************************************************************************
  Write to a file.
 ****************************************************************************/
@@ -230,7 +244,9 @@ ssize_t write_file(struct smb_request *req,
                fsp->modified = True;
 
                if (SMB_VFS_FSTAT(fsp, &st) == 0) {
-                       int dosmode = dos_mode(fsp->conn,fsp->fsp_name,&st);
+                       int dosmode;
+                       trigger_write_time_update(fsp);
+                       dosmode = dos_mode(fsp->conn,fsp->fsp_name,&st);
                        if ((lp_store_dos_attributes(SNUM(fsp->conn)) ||
                                        MAP_ARCHIVE(fsp->conn)) &&
                                        !IS_DOS_ARCHIVE(dosmode)) {