qemu-nbd: Honor SIGINT and SIGHUP

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 <eblake@redhat.com>
Message-Id: <20200930121105.667049-2-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[eblake: apply comment tweak suggested by Vladimir; fix ifdef around
termsig_handler]
Signed-off-by: Eric Blake <eblake@redhat.com>
This commit is contained in:
Eric Blake 2020-09-30 07:11:01 -05:00
parent 99d72dba1c
commit 029a88c9a7

View File

@ -154,13 +154,13 @@ QEMU_COPYRIGHT "\n"
, name); , name);
} }
#if HAVE_NBD_DEVICE #ifdef CONFIG_POSIX
static void termsig_handler(int signum) static void termsig_handler(int signum)
{ {
qatomic_cmpxchg(&state, RUNNING, TERMINATE); qatomic_cmpxchg(&state, RUNNING, TERMINATE);
qemu_notify_event(); qemu_notify_event();
} }
#endif /* HAVE_NBD_DEVICE */ #endif /* CONFIG_POSIX */
static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls, static int qemu_nbd_client_list(SocketAddress *saddr, QCryptoTLSCreds *tls,
const char *hostname) const char *hostname)
@ -581,17 +581,18 @@ int main(int argc, char **argv)
const char *pid_file_name = NULL; const char *pid_file_name = NULL;
BlockExportOptions *export_opts; BlockExportOptions *export_opts;
#if HAVE_NBD_DEVICE #ifdef CONFIG_POSIX
/* The client thread uses SIGTERM to interrupt the server. A signal /*
* handler ensures that "qemu-nbd -v -c" exits with a nice status code. * Exit gracefully on various signals, which includes SIGTERM used
* by 'qemu-nbd -v -c'.
*/ */
struct sigaction sa_sigterm; struct sigaction sa_sigterm;
memset(&sa_sigterm, 0, sizeof(sa_sigterm)); memset(&sa_sigterm, 0, sizeof(sa_sigterm));
sa_sigterm.sa_handler = termsig_handler; sa_sigterm.sa_handler = termsig_handler;
sigaction(SIGTERM, &sa_sigterm, NULL); 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); signal(SIGPIPE, SIG_IGN);
#endif #endif