shutdown: Simplify shutdown_signal

There is no signal 0 (kill(pid, 0) has special semantics to probe whether
a process is alive), rather than actually sending a signal 0).  So we
can use the simpler 0, instead of -1, for our sentinel of whether a
shutdown request due to a signal has happened.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Message-Id: <20170515214114.15442-2-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This commit is contained in:
Eric Blake 2017-05-15 16:41:10 -05:00 committed by Markus Armbruster
parent fc0f005958
commit 7af88279e4

6
vl.c
View File

@ -1598,7 +1598,7 @@ void vm_state_notify(int running, RunState state)
}
static int reset_requested;
static int shutdown_requested, shutdown_signal = -1;
static int shutdown_requested, shutdown_signal;
static pid_t shutdown_pid;
static int powerdown_requested;
static int debug_requested;
@ -1629,7 +1629,7 @@ static int qemu_shutdown_requested(void)
static void qemu_kill_report(void)
{
if (!qtest_driver() && shutdown_signal != -1) {
if (!qtest_driver() && shutdown_signal) {
if (shutdown_pid == 0) {
/* This happens for eg ^C at the terminal, so it's worth
* avoiding printing an odd message in that case.
@ -1643,7 +1643,7 @@ static void qemu_kill_report(void)
shutdown_cmd ? shutdown_cmd : "<unknown process>");
g_free(shutdown_cmd);
}
shutdown_signal = -1;
shutdown_signal = 0;
}
}