mosh-server: Support timeouts on lost connectivity to network client.

Closes #690.

src/tests/Makefile.am

@@ -12,9 +12,11 @@ displaytests = \
 	emulation-80th-column.test \
 	emulation-back-tab.test \
 	emulation-multiline-scroll.test \
-	window-resize.test \
+	server-network-timeout.test \
+	server-signal-timeout.test \
 	unicode-combine-fallback-assert.test \
-	unicode-later-combining.test
+	unicode-later-combining.test \
+	window-resize.test
 
 check_PROGRAMS = ocb-aes encrypt-decrypt base64
 TESTS = ocb-aes encrypt-decrypt base64 $(displaytests)

src/tests/e2e-test-server

@@ -5,6 +5,8 @@
 # then captures screen with `tmux capture-pane`.  Captures exitstatus
 # of both and returns appropriate errors.
 #
+export MOSH_SERVER_PID=$PPID
+
 if [ $# -lt 2 ]; then
     printf "not enough args\n" >&2
     exit 99
@@ -12,6 +14,7 @@ fi
 testname=$1
 shift
 rm -f $testname.capture $testname.exitstatus
+trap ":" TERM HUP QUIT # If the session closes on us, let the test we're running drive.
 trap 'rv=$?; echo $rv > $testname.exitstatus; exit $rv' EXIT
 # check for tmux
 if [ -z "$TMUX_PANE" ]; then

src/tests/server-network-timeout.test

@@ -0,0 +1,114 @@
+#!/bin/sh
+
+#
+# This test checks for operation of the MOSH_SERVER_NETWORK_TIMEOUT variable.
+# It does this by
+# * setting the variable
+# * killing the client (and its network traffic)
+# * waiting server-side, for the server to die
+# If it is killed, the test is successful.
+# If it survives that long and the server is still around, the test fails.
+# The client waits a bit longer than the server so that status can be collected
+# properly.
+#
+
+TIMEOUT=10
+
+fail()
+{
+    printf "$@" 2>&1
+    exit 99
+}
+
+
+
+PATH=$PATH:.:$srcdir
+# Top-level wrapper.
+if [ $# -eq 0 ]; then
+    e2e-test $0 client baseline
+    exit
+fi
+
+# OK, we have arguments, we're one of the test hooks.
+
+client()
+{
+    case "$myname" in
+	server-network-timeout)
+	    export MOSH_SERVER_NETWORK_TMOUT=$TIMEOUT;;
+	server-signal-timeout)
+	    export MOSH_SERVER_SIGNAL_TMOUT=$TIMEOUT;;
+	*)
+	    fail "unexpected test name %s\n" "$myname"
+    esac
+    shift
+    eval "$@"
+    # The client may be murdered.  We need to expect that...
+    retval=$?
+    case $retval in
+	0|1)
+	    fail "mosh-client had a normal exit\n";; # test condition failed
+	137)
+	    # Aha, signal 9.  Wait.
+	    sleep $(( $TIMEOUT + 12 ))
+	    exit 0
+	    ;;
+	*)
+	    fail "unknown client wrapper failure, retval=%d\n" $retval
+	    ;;
+    esac
+    fail "client wrapper shouldnt get here\n"
+}
+baseline()
+{
+    # check for our wonderful variable
+    if [ -z "$MOSH_SERVER_NETWORK_TMOUT" -a -z "$MOSH_SERVER_SIGNAL_TMOUT" ]; then
+	env
+	fail "Variable unset\n"
+    fi
+    # check for our client
+    if [ -z "$MOSH_CLIENT_PID" ]; then
+	env
+	fail "Client pid unavailable\n"
+    fi
+    if ! kill -0 $MOSH_CLIENT_PID; then
+	fail "mosh client is unexpectedly missing\n"
+    fi
+    # Set up for good return and cleanup on being killed
+    trap "echo got killed >&2; sleep 1; exit 0" SIGHUP SIGTERM
+    sleep 1
+    
+    # Kill the client, to stop network traffic.
+    kill -KILL $MOSH_CLIENT_PID
+    case "$myname" in
+	server-network-timeout)
+	    # Just wait.  This is the hardest part.
+	    sleep $(( $TIMEOUT + 7 ))
+	    ;;
+	server-signal-timeout)
+	    # Wait for the timeout to expire.
+	    sleep $(( $TIMEOUT + 2 ))
+	    # Tell the server to go away.
+	    kill -USR1 $MOSH_SERVER_PID
+	    sleep 5
+	    ;;
+	*)
+	    fail "unexpected test name %s\n" "$myname"
+    esac
+    # If we're still alive and the server is too, the test failed.
+    # XXX the server is getting killed and we're getting here anyway.
+    # Exit with error only if server is still around.
+    ! kill -0 $MOSH_SERVER_PID
+    exit
+}
+
+myname="$(basename $0 .test)"
+
+case $1 in
+    baseline|variant)
+	baseline;;
+    client)
+	client "$@";;
+    *)
+	fail "unknown test argument %s\n" $1;;
+esac

src/tests/server-signal-timeout.test

@@ -0,0 +1 @@
+server-network-timeout.test