Honoring just SIGTERM on Linux is too weak; we also want to handle other common signals, and do so even on BSD. Why? Because at least 'qemu-nbd -B bitmap' needs a chance to clean up the in-use bit on bitmaps when the server is shut down via a signal.
See also: http://bugzilla.redhat.com/1883608 Signed-off-by: Eric Blake <ebl...@redhat.com> Message-Id: <20200930121105.667049-2-ebl...@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> [eblake: apply comment tweak suggested by Vladimir; fix ifdef around termsig_handler] Signed-off-by: Eric Blake <ebl...@redhat.com> --- qemu-nbd.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/qemu-nbd.c b/qemu-nbd.c index bacb69b0898b..bc644a0670b6 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -154,13 +154,13 @@ QEMU_COPYRIGHT "\n" , name); } -#if HAVE_NBD_DEVICE +#ifdef CONFIG_POSIX static void termsig_handler(int signum) { qatomic_cmpxchg(&state, RUNNING, TERMINATE); qemu_notify_event(); } -#endif /* HAVE_NBD_DEVICE */ +#endif /* CONFIG_POSIX */ static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, const char *hostname) @@ -581,17 +581,18 @@ int main(int argc, char **argv) const char *pid_file_name = NULL; BlockExportOptions *export_opts; -#if HAVE_NBD_DEVICE - /* The client thread uses SIGTERM to interrupt the server. A signal - * handler ensures that "qemu-nbd -v -c" exits with a nice status code. +#ifdef CONFIG_POSIX + /* + * Exit gracefully on various signals, which includes SIGTERM used + * by 'qemu-nbd -v -c'. */ struct sigaction sa_sigterm; memset(&sa_sigterm, 0, sizeof(sa_sigterm)); sa_sigterm.sa_handler = termsig_handler; sigaction(SIGTERM, &sa_sigterm, NULL); -#endif /* HAVE_NBD_DEVICE */ + sigaction(SIGINT, &sa_sigterm, NULL); + sigaction(SIGHUP, &sa_sigterm, NULL); -#ifdef CONFIG_POSIX signal(SIGPIPE, SIG_IGN); #endif -- 2.28.0
