The message file header parsing code parses only enough of the file to
find the desired header fields, then it leaves the file open until the
next header parsing call or when the message is no longer in use. If a
large number of messages end up being active, this will quickly run
out of file descriptors.
Here, we add support to explicitly close the message file within a
message, (_notmuch_message_close) and call that from thread
construction code.
Signed-off-by: Keith Packard <keithp@keithp.com>
Edited-by: Carl Worth <cworth@cworth.org>:
Many portions of Keith's original patch have since been solved other
ways, (such as the code that changed the handling of the In-Reply-To
header). So the final version is clean enough that I think even Keith
would be happy to have his name on it.
This reduces our reliance on open message_file objects, (so is a step
toward fixing the "too many open files" bug), but more importantly, it
means we don't load a self-referencing in-reply-to header, (since we
weed those out before adding any replyto terms to the database).
We now properly analyze the in-reply-to headers to create a proper
tree representing the actual thread and present the messages in this
correct thread order. Also, there's a new "depth:" value added to the
"message{" header so that clients can format the thread as desired,
(such as by indenting replies).
We were properly sorting the threads based only on matched messages,
but we were displaying the date based on the total messages in the
thread, which led to inconsistent and very confusing results.
Note that the difference between thread results in date order and
thread results in reverse-date order is not simply a matter of
reversing the final results. When sorting in date order, the threads
are sorted by the oldest message in the thread. When sorting in
reverse-date order, the threads are sorted by the newest message in
the thread.
This difference means that we might want an explicit option in the
interface to reverse the order, (even though the default will be to
display the inbox in date order and global searches in reverse-date
order).
Note that we don't print the number of *unread* messages, but instead
the number of messages that matched the search terms. This is in
keeping with our philosophy that the inbox is nothing more than a
search view. If we search for messages with an inbox tag, then that's
what we'll get a count of. (And if somebody does want to see unread
counts, then they can search for the "unread" tag.)
Getting the number of matched messages is really nice when doing
historical searches. For example in a search like:
notmuch search tag:sent
(where the "sent" tag has been applied to all messages originating
from the user's email address)---here it's really nice to be able to
see a thread where the user just mentioned one point [1/13] vs. really
getting involved in the discussion [10/29].
We add a hash to the thread object so that we can detect author names
that have already been added to the list, and avoid adding them
redundantly. This avoids the giant chain of "bugzilla-daemon,
bugzilla-daemon, bugzilla-daemon, bugzilla-daemon, ..." author lists
that we would get otherwise, for example.
We've now expanded the notmuch_thread_create function to fire off a
secondary database query to find all the messages that belong to this
particular thread. This allows us to now have the complete authors'
list for the thread, and will also make it trivial to print accurate
message counts for threads in the future.
It's important to have the names present for determining whether a
thread is worth reading or not. We may want to think about
abbreviating the list somehow if it is excessively long (or redundant
as in bugzilla-daemon, bugzilla-daemon, bugzilla-daemon, etc.).
