test: Integration test for reload

This patch implements an integration test for reloading; in particular
it exercises reloading aliases and user databases.

test/t-13-reload/run.sh

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+set -e
+. $(dirname ${0})/../util/lib.sh
+
+init
+
+generate_certs_for testserver
+
+# Start with the user with the wrong password, and no aliases.
+add_user someone@testserver password111
+rm -f config/domains/testserver/aliases
+
+mkdir -p .logs
+chasquid -v=2 --logfile=.logs/chasquid.log --config_dir=config \
+	--testing__reload_every=50ms &
+wait_until_ready 1025
+
+# First, check that delivery fails with the "wrong" password.
+if run_msmtp someone@testserver < content 2>/dev/null; then
+	fail "success using the wrong password"
+fi
+
+# Change password, add an alias; then wait a bit more than the reload period
+# and try again.
+add_user someone@testserver password222
+echo "analias: someone" > config/domains/testserver/aliases
+sleep 0.2
+
+run_msmtp analias@testserver < content
+wait_for_file .mail/someone@testserver
+
+success