Keep the inode cache in sync when writing to the MailDir

MailDir writes cause the inode mtime and ctime to change which causes
the cache to become invalid. Update the mtime and ctime information after
changing it.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

2 files changed, 8 insertions, 0 deletions

diff --git a/cloud_mdir_sync/maildir.py b/cloud_mdir_sync/maildir.py
index c7f1be5..51497be 100644
--- a/cloud_mdir_sync/maildir.py
+++ b/cloud_mdir_sync/maildir.py
@@ -149,6 +149,7 @@ class MailDirMailbox(mailbox.Mailbox):
         # delivered it.
         if cloudmsg.received_time is not None:
             os.utime(fn, (time.time(), cloudmsg.received_time.timestamp()))
+        self.msgdb.update_inode_cache(msg)
         self.messages[msg.content_hash] = msg
 
     def _set_flags(self, mymsg: messages.Message, cloudmsg: messages.Message):
diff --git a/cloud_mdir_sync/messages.py b/cloud_mdir_sync/messages.py
index d7044ae..73cbf80 100644
--- a/cloud_mdir_sync/messages.py
+++ b/cloud_mdir_sync/messages.py
@@ -281,6 +281,13 @@ class MessageDB(object):
         self.alt_file_hashes[msg.content_hash].add(fn)
         msg.fill_email_id()
 
+    def update_inode_cache(self, msg):
+        """After the message has been hardlinked or the times adjusted,
+        the inode cache needs to be updated with the new times"""
+        st = os.stat(msg.fn)
+        inode = (st.st_ino, st.st_size, st.st_mtime, st.st_ctime)
+        self.inode_hashes[inode] = msg.content_hash
+
     def write_content(self, content_hash, dest_fn):
         """Make the filename dest_fn contain content_hash's content"""
         assert content_hash in self.file_hashes