[PATCH 09/10] extindex: SIGUSR1 supports checkpoint

[Eric Wong <e@80x24.org>]

Matching the behavior of git-fast-import(1), we'll allow a user
to send SIGUSR1 to checkpoint over.sqlite3 and Xapian.
---
 lib/PublicInbox/ExtSearchIdx.pm | 23 ++++++++++++-----------
 script/public-inbox-extindex    |  1 +
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/lib/PublicInbox/ExtSearchIdx.pm b/lib/PublicInbox/ExtSearchIdx.pm
index 50342802..7aaf8291 100644
--- a/lib/PublicInbox/ExtSearchIdx.pm
+++ b/lib/PublicInbox/ExtSearchIdx.pm
@@ -284,16 +284,9 @@ sub last_commits {
 }
 
 sub _sync_inbox ($$$) {
-	my ($self, $opt, $ibx) = @_;
-	my $sync = {
-		need_checkpoint => \(my $bool = 0),
-		reindex => $opt->{reindex},
-		-opt => $opt,
-		self => $self,
-		ibx => $ibx,
-		nr => \(my $nr = 0),
-		-regen_fmt => "%u/?\n",
-	};
+	my ($self, $sync, $ibx) = @_;
+	$sync->{ibx} = $ibx;
+	$sync->{nr} = \(my $nr = 0);
 	my $v = $ibx->version;
 	my $ekey = $ibx->eidx_key;
 	if ($v == 2) {
@@ -324,10 +317,18 @@ sub eidx_sync { # main entry point
 	local $SIG{__WARN__} = sub {
 		$warn_cb->($self->{current_info}, ': ', @_);
 	};
+	my $sync = {
+		need_checkpoint => \(my $need_checkpoint = 0),
+		reindex => $opt->{reindex},
+		-opt => $opt,
+		self => $self,
+		-regen_fmt => "%u/?\n",
+	};
+	local $SIG{USR1} = sub { $need_checkpoint = 1 };
 
 	# don't use $_ here, it'll get clobbered by reindex_checkpoint
 	for my $ibx (@{$self->{ibx_list}}) {
-		_sync_inbox($self, $opt, $ibx);
+		_sync_inbox($self, $sync, $ibx);
 	}
 
 	$self->{oidx}->rethread_done($opt);
diff --git a/script/public-inbox-extindex b/script/public-inbox-extindex
index bb1e174a..864a2732 100644
--- a/script/public-inbox-extindex
+++ b/script/public-inbox-extindex
@@ -33,6 +33,7 @@ die "--jobs must be >= 0\n" if defined $opt->{jobs} && $opt->{jobs} < 0;
 
 # require lazily to speed up --help
 my $eidx_dir = shift(@ARGV) // die "E: $help";
+local $SIG{USR1} = 'IGNORE'; # to be overridden in eidx_sync
 require PublicInbox::Admin;
 my $cfg = PublicInbox::Config->new;
 my @ibxs = PublicInbox::Admin::resolve_inboxes(\@ARGV, $opt, $cfg);