user/dev discussion of public-inbox itself
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From: Eric Wong <e@yhbt.net>
To: meta@public-inbox.org
Subject: [PATCH 70/82] imap: reinstate some message sequence number support
Date: Wed, 10 Jun 2020 07:05:07 +0000	[thread overview]
Message-ID: <20200610070519.18252-71-e@yhbt.net> (raw)
In-Reply-To: <20200610070519.18252-1-e@yhbt.net>

The performance problem with mutt not using header caches isn't
fixed, yet, but mutt header caching seems to depend on MSNs
(message sequence numbers).  We'll switch to storing the 0-based
{uid_base} instead of the 1-based {uid_min} since it simplifies
most of our code.
---
 lib/PublicInbox/IMAP.pm | 121 ++++++++++++++++++++++++----------------
 1 file changed, 73 insertions(+), 48 deletions(-)

diff --git a/lib/PublicInbox/IMAP.pm b/lib/PublicInbox/IMAP.pm
index 2e50415de57..12123072d1a 100644
--- a/lib/PublicInbox/IMAP.pm
+++ b/lib/PublicInbox/IMAP.pm
@@ -7,17 +7,13 @@
 # slow storage.
 #
 # data notes:
-# * NNTP article numbers are UIDs and message sequence numbers (MSNs)
-# * Message sequence numbers (MSNs) can be stable since we're read-only.
-#   Most IMAP clients use UIDs (I hope).  We may return a dummy message
-#   in the future if a client requests a non-existent MSN, but that seems
-#   unecessary with mutt.
+# * NNTP article numbers are UIDs
 
 package PublicInbox::IMAP;
 use strict;
 use base qw(PublicInbox::DS);
 use fields qw(imapd ibx long_cb -login_tag
-	uid_min -idle_tag -idle_max);
+	uid_base -idle_tag -idle_max);
 use PublicInbox::Eml;
 use PublicInbox::EmlContentFoo qw(parse_content_disposition);
 use PublicInbox::DS qw(now);
@@ -151,7 +147,7 @@ sub cmd_login ($$$$) {
 
 sub cmd_close ($$) {
 	my ($self, $tag) = @_;
-	delete $self->{uid_min};
+	delete $self->{uid_base};
 	delete $self->{ibx} ? "$tag OK Close done\r\n"
 				: "$tag BAD No mailbox\r\n";
 }
@@ -181,11 +177,14 @@ sub cmd_noop ($$) { "$_[1] OK Noop done\r\n" }
 sub on_inbox_unlock {
 	my ($self, $ibx) = @_;
 	my $new = $ibx->mm->max;
-	my $uid_end = ($self->{uid_min} // 1) - 1 + UID_BLOCK;
+	my $uid_base = $self->{uid_base} // 0;
+	my $uid_end = $uid_base + UID_BLOCK;
 	defined(my $old = $self->{-idle_max}) or die 'BUG: -idle_max unset';
 	$new = $uid_end if $new > $uid_end;
 	if ($new > $old) {
 		$self->{-idle_max} = $new;
+		$new -= $uid_base;
+		$old -= $uid_base;
 		$self->msg_more("* $_ EXISTS\r\n") for (($old + 1)..($new - 1));
 		$self->write(\"* $new EXISTS\r\n");
 	} elsif ($new == $uid_end) { # max exceeded $uid_end
@@ -218,7 +217,7 @@ sub cmd_idle ($$) {
 	my $ibx = $self->{ibx} or return "$tag BAD no mailbox selected\r\n";
 	$self->{-idle_tag} = $tag;
 	my $max = $ibx->mm->max // 0;
-	my $uid_end = ($self->{uid_min} // 1) - 1 + UID_BLOCK;
+	my $uid_end = ($self->{uid_base} // 0) + UID_BLOCK;
 	my $sock = $self->{sock} or return;
 	my $fd = fileno($sock);
 	# only do inotify on most recent slice
@@ -274,18 +273,19 @@ sub inbox_lookup ($$) {
 	my ($ibx, $exists, $uidnext);
 	if ($mailbox =~ /\A(.+)\.([0-9]+)\z/) {
 		# old mail: inbox.comp.foo.$uid_block_idx
-		my ($mb_top, $uid_min) = ($1, $2 * UID_BLOCK + 1);
+		my ($mb_top, $uid_base) = ($1, $2 * UID_BLOCK);
 
 		$ibx = $self->{imapd}->{mailboxes}->{lc $mailbox} or return;
 		$exists = $ibx->mm->max // 0;
-		$self->{uid_min} = $uid_min;
+		$self->{uid_base} = $uid_base;
 		ensure_ranges_exist($self->{imapd}, $ibx, $exists);
-		my $uid_end = $uid_min + UID_BLOCK - 1;
+		my $uid_end = $uid_base + UID_BLOCK;
 		$exists = $uid_end if $exists > $uid_end;
 		$uidnext = $exists + 1;
+		$exists -= $uid_base;
 	} else { # check for dummy inboxes
 		$ibx = $self->{imapd}->{mailboxes}->{lc $mailbox} or return;
-		delete $self->{uid_min};
+		delete $self->{uid_base};
 		$exists = 0;
 		$uidnext = 1;
 	}
@@ -469,9 +469,24 @@ sub requeue_once ($) {
 	$self->requeue if $new_size == 1;
 }
 
-sub uid_fetch_cb { # called by git->cat_async via git_async_cat
-	my ($bref, $oid, $type, $size, $fetch_m_arg) = @_;
-	my ($self, undef, $msgs, undef, $ops, $partial) = @$fetch_m_arg;
+# my ($uid_base, $UID) = @_;
+sub fetch_msn_uid ($$) { '* '.($_[1] - $_[0]).' FETCH (UID '.$_[1] }
+
+sub fetch_run_ops {
+	my ($self, $uid_base, $smsg, $bref, $ops, $partial) = @_;
+	$self->msg_more(fetch_msn_uid($uid_base, $smsg->{num}));
+	my ($eml, $k);
+	for (my $i = 0; $i < @$ops;) {
+		$k = $ops->[$i++];
+		$ops->[$i++]->($self, $k, $smsg, $bref, $eml);
+	}
+	partial_emit($self, $partial, $eml) if $partial;
+	$self->msg_more(")\r\n");
+}
+
+sub fetch_blob_cb { # called by git->cat_async via git_async_cat
+	my ($bref, $oid, $type, $size, $fetch_arg) = @_;
+	my ($self, undef, $msgs, undef, $ops, $partial) = @$fetch_arg;
 	my $smsg = shift @$msgs or die 'BUG: no smsg';
 	if (!defined($oid)) {
 		# it's possible to have TOCTOU if an admin runs
@@ -484,14 +499,8 @@ sub uid_fetch_cb { # called by git->cat_async via git_async_cat
 
 	# fixup old bug from import (pre-a0c07cba0e5d8b6a)
 	$$bref =~ s/\A[\r\n]*From [^\r\n]*\r\n//s;
-	$self->msg_more("* $smsg->{num} FETCH (UID $smsg->{num}");
-	my $eml;
-	for (my $i = 0; $i < @$ops;) {
-		my $k = $ops->[$i++];
-		$ops->[$i++]->($self, $k, $smsg, $bref, $eml);
-	}
-	partial_emit($self, $partial, $eml) if $partial;
-	$self->msg_more(")\r\n");
+	fetch_run_ops($self, $self->{uid_base} // 0,
+			$smsg, $bref, $ops, $partial);
 	requeue_once($self);
 }
 
@@ -549,7 +558,7 @@ sub op_eml_new { $_[4] = PublicInbox::Eml->new($_[3]) }
 
 sub uid_clamp ($$$) {
 	my ($self, $beg, $end) = @_;
-	my $uid_min = $self->{uid_min} or return;
+	my $uid_min = ($self->{uid_base} // 0) + 1;
 	my $uid_end = $uid_min + UID_BLOCK - 1;
 	$$beg = $uid_min if $$beg < $uid_min;
 	$$end = $uid_end if $$end > $uid_end;
@@ -569,7 +578,7 @@ sub range_step ($$) {
 	} elsif ($range =~ /\A([0-9]+):\*\z/) {
 		$beg = $1 + 0;
 		$end = $self->{ibx}->mm->max // 0;
-		my $uid_end = ($self->{uid_min} // 1) - 1 + UID_BLOCK;
+		my $uid_end = $self->{uid_base} + UID_BLOCK;
 		$end = $uid_end if $end > $uid_end;
 		$beg = $end if $beg > $end;
 	} elsif ($range =~ /\A[0-9]+\z/) {
@@ -596,8 +605,8 @@ sub refill_range ($$$) {
 	undef; # keep looping
 }
 
-sub uid_fetch_msg { # long_response
-	my ($self, $tag, $msgs, $range_info) = @_; # \@ops, \@partial
+sub fetch_blob { # long_response
+	my ($self, $tag, $msgs, $range_info, $ops, $partial) = @_;
 	while (!@$msgs) { # rare
 		if (my $end = refill_range($self, $msgs, $range_info)) {
 			$self->write(\"$tag $end\r\n");
@@ -605,10 +614,10 @@ sub uid_fetch_msg { # long_response
 		}
 	}
 	git_async_cat($self->{ibx}->git, $msgs->[0]->{blob},
-			\&uid_fetch_cb, \@_);
+			\&fetch_blob_cb, \@_);
 }
 
-sub uid_fetch_smsg { # long_response
+sub fetch_smsg { # long_response
 	my ($self, $tag, $msgs, $range_info, $ops) = @_;
 	while (!@$msgs) { # rare
 		if (my $end = refill_range($self, $msgs, $range_info)) {
@@ -616,20 +625,15 @@ sub uid_fetch_smsg { # long_response
 			return;
 		}
 	}
-	for my $smsg (@$msgs) {
-		$self->msg_more("* $smsg->{num} FETCH (UID $smsg->{num}");
-		for (my $i = 0; $i < @$ops;) {
-			my $k = $ops->[$i++];
-			$ops->[$i++]->($self, $k, $smsg);
-		}
-		$self->msg_more(")\r\n");
-	}
+	my $uid_base = $self->{uid_base} // 0;
+	fetch_run_ops($self, $uid_base, $_, undef, $ops) for @$msgs;
 	@$msgs = ();
 	1; # more
 }
 
-sub uid_fetch_uid { # long_response
+sub fetch_uid { # long_response
 	my ($self, $tag, $uids, $range_info, $ops) = @_;
+
 	while (!@$uids) { # rare
 		my ($beg, $end, $range_csv) = @$range_info;
 		if (scalar(@$uids = @{$self->{ibx}->over->
@@ -648,10 +652,12 @@ sub uid_fetch_uid { # long_response
 		}
 		# continue looping
 	}
+	my $uid_base = $self->{uid_base} // 0;
+	my ($i, $k);
 	for (@$uids) {
-		$self->msg_more("* $_ FETCH (UID $_");
-		for (my $i = 0; $i < @$ops;) {
-			my $k = $ops->[$i++];
+		$self->msg_more(fetch_msn_uid($uid_base, $_));
+		for ($i = 0; $i < @$ops;) {
+			$k = $ops->[$i++];
 			$ops->[$i++]->($self, $k);
 		}
 		$self->msg_more(")\r\n");
@@ -875,8 +881,8 @@ sub fetch_compile ($) {
 		$r[2] = [ map { [ $_, @{$partial{$_}} ] } sort keys %partial ];
 	}
 
-	$r[0] = $need & NEED_BLOB ? \&uid_fetch_msg :
-		($need & NEED_SMSG ? \&uid_fetch_smsg : \&uid_fetch_uid);
+	$r[0] = $need & NEED_BLOB ? \&fetch_blob :
+		($need & NEED_SMSG ? \&fetch_smsg : \&fetch_uid);
 
 	# r[1] = [ $key1, $cb1, $key2, $cb2, ... ]
 	use sort 'stable'; # makes output more consistent
@@ -896,6 +902,25 @@ sub cmd_uid_fetch ($$$$;@) {
 	long_response($self, $cb, $tag, [], $range_info, $ops, $partial);
 }
 
+sub msn_to_uid_range ($$) {
+	my $uid_base = $_[0]->{uid_base} // 0;
+	$_[1] =~ s/([0-9]+)/$uid_base + $1/sge;
+}
+
+sub cmd_fetch ($$$$;@) {
+	my ($self, $tag, $range_csv, @want) = @_;
+	my $ibx = $self->{ibx} or return "$tag BAD No mailbox selected\r\n";
+	my ($cb, $ops, $partial) = fetch_compile(\@want);
+	return "$tag $cb\r\n" unless $ops;
+
+	# cb is one of fetch_blob, fetch_smsg, fetch_uid
+	$range_csv = 'bad' if $range_csv !~ $valid_range;
+	msn_to_uid_range($self, $range_csv);
+	my $range_info = range_step($self, \$range_csv);
+	return "$tag $range_info\r\n" if !ref($range_info);
+	long_response($self, $cb, $tag, [], $range_info, $ops, $partial);
+}
+
 sub parse_date ($) { # 02-Oct-1993
 	my ($date_text) = @_;
 	my ($dd, $mon, $yyyy) = split(/-/, $_[0], 3);
@@ -979,7 +1004,8 @@ sub parse_query {
 		# default criteria
 		next if $k =~ /\A(?:ALL|RECENT|UNSEEN|NEW)\z/;
 		next if $k eq 'AND'; # the default, until we support OR
-		if ($k =~ $valid_range) { # sequence numbers == UIDs
+		if ($k =~ $valid_range) { # convert sequence numbers to UIDs
+			msn_to_uid_range($self, $k);
 			push @{$q->{uid}}, $k;
 		} elsif ($k eq 'UID') {
 			$k = shift(@$rest) // '';
@@ -1037,8 +1063,8 @@ sub cmd_uid_search ($$$;) {
 
 	if (!scalar(keys %$q)) {
 		$self->msg_more('* SEARCH');
-		my $beg = $self->{uid_min} // 1;
-		my $end = $ibx->mm->max;
+		my $beg = 1;
+		my $end = $ibx->mm->max // 0;
 		uid_clamp($self, \$beg, \$end);
 		long_response($self, \&uid_search_uid_range,
 				$tag, \$beg, $end, $sql);
@@ -1244,7 +1270,6 @@ sub close {
 # we're read-only, so SELECT and EXAMINE do the same thing
 no warnings 'once';
 *cmd_select = \&cmd_examine;
-*cmd_fetch = \&cmd_uid_fetch;
 
 package PublicInbox::IMAP_preauth;
 our @ISA = qw(PublicInbox::IMAP);

  parent reply	other threads:[~2020-06-10  7:07 UTC|newest]

Thread overview: 84+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-10  7:03 [PATCH 00/82] public-inbox-imapd: read-only IMAP server Eric Wong
2020-06-10  7:03 ` [PATCH 01/82] doc: add some IMAP standards Eric Wong
2020-06-10  7:03 ` [PATCH 02/82] nntpd: restrict allowed newsgroup names Eric Wong
2020-06-10  7:04 ` [PATCH 03/82] preliminary imap server implementation Eric Wong
2020-06-10  7:04 ` [PATCH 04/82] inboxidle: new class to detect inbox changes Eric Wong
2020-06-10  7:04 ` [PATCH 05/82] imap: support IDLE Eric Wong
2020-06-10  7:04 ` [PATCH 06/82] msgmap: split ->max into its own method Eric Wong
2020-06-10  7:04 ` [PATCH 07/82] imap: delay InboxIdle start, support refresh Eric Wong
2020-06-10  7:04 ` [PATCH 08/82] imap: implement STATUS command Eric Wong
2020-06-10  7:04 ` [PATCH 09/82] imap: use Text::ParseWords::parse_line to handle quoted words Eric Wong
2020-06-10  7:04 ` [PATCH 10/82] imap: support LIST command Eric Wong
2020-06-10  7:04 ` [PATCH 11/82] t/imapd: support FakeInotify and KQNotify Eric Wong
2020-06-10  7:04 ` [PATCH 12/82] imap: support fetch for BODYSTRUCTURE and BODY Eric Wong
2020-06-10  7:04 ` [PATCH 13/82] eml: each_part: single part $idx is 1 Eric Wong
2020-06-10  7:04 ` [PATCH 14/82] imap: allow fetch of partial of BODY[...] and headers Eric Wong
2020-06-10  7:04 ` [PATCH 15/82] imap: always include `resp-text' in responses Eric Wong
2020-06-10  7:04 ` [PATCH 16/82] imap: split out unit tests and benchmarks Eric Wong
2020-06-10  7:04 ` [PATCH 17/82] imap: fix multi-message partial header fetches Eric Wong
2020-06-10  7:04 ` [PATCH 18/82] imap: simplify partial fetch structure Eric Wong
2020-06-10  7:04 ` [PATCH 19/82] imap: support sequence number FETCH Eric Wong
2020-06-10  7:04 ` [PATCH 20/82] imap: do not include ".PEEK" in responses Eric Wong
2020-06-10  7:04 ` [PATCH 21/82] imap: support the CLOSE command Eric Wong
2020-06-10  7:04 ` [PATCH 22/82] imap: speed up HEADER.FIELDS[.NOT] range fetches Eric Wong
2020-06-10  7:04 ` [PATCH 23/82] git: async: flatten the inflight array Eric Wong
2020-06-10  7:04 ` [PATCH 24/82] git: do our own read buffering for cat-file Eric Wong
2020-06-10  7:04 ` [PATCH 25/82] imap: use git-cat-file asynchronously Eric Wong
2020-06-10  7:04 ` [PATCH 26/82] git: idle rbuf for async Eric Wong
2020-06-10  7:04 ` [PATCH 27/82] imap: support LSUB command Eric Wong
2020-06-10  7:04 ` [PATCH 28/82] imap: FETCH: support comma-delimited ranges Eric Wong
2020-06-10  7:04 ` [PATCH 29/82] add imapd compression test Eric Wong
2020-06-10  7:04 ` [PATCH 30/82] testcommon: tcp_(server|connect): BAIL_OUT on failure Eric Wong
2020-06-10  7:04 ` [PATCH 31/82] *deflate: drop invalid comment about rbuf Eric Wong
2020-06-10  7:04 ` [PATCH 32/82] imap: fix pipelining with async git Eric Wong
2020-06-10  7:04 ` [PATCH 33/82] git: cat_async: provide requested OID + "missing" on missing blobs Eric Wong
2020-06-10  7:04 ` [PATCH 34/82] git: move async_cat reference to PublicInbox::Git Eric Wong
2020-06-10  7:04 ` [PATCH 35/82] git: async: automatic retry on alternates change Eric Wong
2020-06-10  7:04 ` [PATCH 36/82] imapclient: wrapper for Mail::IMAPClient Eric Wong
2020-06-10  7:04 ` [PATCH 37/82] xt: add imapd-validate and imapd-mbsync-oimap Eric Wong
2020-06-10  7:04 ` [PATCH 38/82] imap: support out-of-bounds ranges Eric Wong
2020-06-10  7:04 ` [PATCH 39/82] xt/perf-imap-list: time refresh_inboxlist Eric Wong
2020-06-10  7:04 ` [PATCH 40/82] imap: case-insensitive mailbox name comparisons Eric Wong
2020-06-10  7:04 ` [PATCH 41/82] imap: break giant inboxes into sub-inboxes of 50K messages Eric Wong
2020-06-10  7:04 ` [PATCH 42/82] imap: start doing iterative config reloading Eric Wong
2020-06-10  7:04 ` [PATCH 43/82] imap: require ".$UID_MIN-$UID_END" suffix Eric Wong
2020-06-10  7:04 ` [PATCH 44/82] imapd: ensure LIST is sorted alphabetically, for now Eric Wong
2020-06-10  7:04 ` [PATCH 45/82] imap: omit $UID_END from mailbox name, use index Eric Wong
2020-06-10  7:04 ` [PATCH 46/82] t/config.t: always compare against git bool behavior Eric Wong
2020-06-10  7:04 ` [PATCH 47/82] xt/*: show some tunable parameters Eric Wong
2020-06-10  7:04 ` [PATCH 48/82] imap: STATUS and LIST are case-insensitive, too Eric Wong
2020-06-10  7:04 ` [PATCH 49/82] imap: EXAMINE/STATUS: return correct counts Eric Wong
2020-06-10  7:04 ` [PATCH 50/82] imap: avoid uninitialized warnings on incomplete commands Eric Wong
2020-06-10  7:04 ` [PATCH 51/82] imap: start parsing out queries for SQLite and Xapian Eric Wong
2020-06-10  7:04 ` [PATCH 52/82] imap: SEARCH: clamp results to the 50K UID range Eric Wong
2020-06-10  7:04 ` [PATCH 53/82] imap: allow UID range search on timestamps Eric Wong
2020-06-10  7:04 ` [PATCH 54/82] over: get_art: use dbh->prepare_cached Eric Wong
2020-06-10  7:04 ` [PATCH 55/82] search: index byte size of a message for IMAP search Eric Wong
2020-06-10  7:04 ` [PATCH 56/82] search: index UID for IMAP search, too Eric Wong
2020-06-10  7:04 ` [PATCH 57/82] imap: remove dummies from sequence number FETCH Eric Wong
2020-06-10  7:04 ` [PATCH 58/82] imap: compile UID FETCH to opcodes Eric Wong
2020-06-10  7:04 ` [PATCH 59/82] imap: UID FETCH: optimize for smsg-only case Eric Wong
2020-06-10  7:04 ` [PATCH 60/82] imap: UID FETCH: optimize (UID FLAGS) harder Eric Wong
2020-06-10  7:04 ` [PATCH 61/82] imap: IDLE: avoid extraneous wakeups, keep-alive Eric Wong
2020-06-10  7:04 ` [PATCH 62/82] imap: 30 minute auto-logout timer Eric Wong
2020-06-10  7:05 ` [PATCH 63/82] imap: split ->logged_in attribute into a separate class Eric Wong
2020-06-10  7:05 ` [PATCH 64/82] searchidx: v1 (re)-index uses git asynchronously Eric Wong
2020-06-10  7:05 ` [PATCH 65/82] index: account for CRLF conversion when storing bytes Eric Wong
2020-06-10  7:05 ` [PATCH 66/82] imap: rely on smsg->{bytes} for RFC822.SIZE Eric Wong
2020-06-10  7:05 ` [PATCH 67/82] imap: UID FETCH requires at least one data item Eric Wong
2020-06-10  7:05 ` [PATCH 68/82] imap: LIST shows "INBOX" in all caps Eric Wong
2020-06-10  7:05 ` [PATCH 69/82] imap: support 8000 octet lines Eric Wong
2020-06-10  7:05 ` Eric Wong [this message]
2020-06-10  7:05 ` [PATCH 71/82] imap: cleanup ->{uid_base} usage Eric Wong
2020-06-10  7:05 ` [PATCH 72/82] imap: FETCH: more granular CRLF conversion Eric Wong
2020-06-10  7:05 ` [PATCH 73/82] imap: further speed up HEADER.FIELDS FETCH requests Eric Wong
2020-06-10  7:05 ` [PATCH 74/82] imap: FETCH: try to make fake MSNs sequentially Eric Wong
2020-06-10  7:05 ` [PATCH 75/82] imap: STATUS/EXAMINE: rely on SQLite overview Eric Wong
2020-06-10  7:05 ` [PATCH 76/82] imap: UID SEARCH: support multiple ranges Eric Wong
2020-06-10  7:05 ` [PATCH 77/82] imap: wire up Xapian, MSN SEARCH and multi sequence-sets Eric Wong
2020-06-10  7:05 ` [PATCH 78/82] imap: misc cleanups and notes Eric Wong
2020-06-10  7:05 ` [PATCH 79/82] imapd: don't bother sorting LIST output Eric Wong
2020-06-10  7:05 ` [PATCH 80/82] imap: remove non-UID SEARCH for now Eric Wong
2020-06-10  7:05 ` [PATCH 81/82] over: uid_range: remove LIMIT Eric Wong
2020-06-10  7:05 ` [PATCH 82/82] imap: FETCH: proper MSN => UID mapping for requests Eric Wong
2020-06-12 23:49 ` [PATCH 83/82] imap: introduce memory-efficient uo2m mapping Eric Wong

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