t/lei-sigpipe: ensure SIGPIPE is unblocked for this test

Tests run under systemd (and similar) have SIGPIPE blocked by
default.  This was causing this SIGPIPE test to get stuck when
run by automated builders used by Nix.  Thanks to Julien
Moutinho and Dominique Martinet for tracking down this failure.

Reported-by: Julien Moutinho <julm+public-inbox@sourcephile.fr>
Reported-by: Dominique Martinet <asmadeus@codewreck.org>
Link: https://public-inbox.org/meta/20220227080422.gyqowrxomzu6gyin@sourcephile.fr/

diff --git a/t/lei-sigpipe.t b/t/lei-sigpipe.t
index 6b2772a69a60796aa3277e76126560815bd9dcb0..7fab9aebb0ff0a1faae0a57b2532ff9d2853aa7b 100644 (file)
--- a/t/lei-sigpipe.t
+++ b/t/lei-sigpipe.t
@@ -1,10 +1,25 @@
 #!perl -w
-# Copyright (C) 2021 all contributors <meta@public-inbox.org>
+# Copyright (C) all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 use strict;
 use v5.10.1;
 use PublicInbox::TestCommon;
-use POSIX qw(WTERMSIG WIFSIGNALED SIGPIPE);
+use POSIX qw(WTERMSIG WIFSIGNALED SIGPIPE SIG_UNBLOCK SIG_SETMASK sigprocmask);
+use PublicInbox::OnDestroy;
+
+# undo systemd (and similar) blocking SIGPIPE, since lei expects to be run
+# from an interactive terminal:
+# https://public-inbox.org/meta/20220227080422.gyqowrxomzu6gyin@sourcephile.fr/
+my $set = POSIX::SigSet->new;
+my $old = POSIX::SigSet->new;
+$set->emptyset or xbail "sigemptyset $!";
+$old->emptyset or xbail "sigemptyset $!";
+$set->addset(SIGPIPE);
+sigprocmask(SIG_UNBLOCK, $set, $old) or xbail "SIG_UNBLOCK: $!";
+my $cleanup = PublicInbox::OnDestroy->new($$, sub {
+       sigprocmask(SIG_SETMASK, $old);
+});
+
 test_lei(sub {
        my $f = "$ENV{HOME}/big.eml";
        my $imported;