[PATCH 10/21] system: simplify signal handler logic

["Daniel P. Berrangé" <berrange@redhat.com>]

sigaction() can fail if

 * The signal number is invalid
 * The signal number is KILL / STOP
 * The sigaction struct points to invalid memory

None of these scenarios can arise with our use of sigaction(), so
rather than try to handle failures, assert that the call passed.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 system/signal.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/system/signal.c b/system/signal.c
index f667b56255d..88316089fc0 100644
--- a/system/signal.c
+++ b/system/signal.c
@@ -56,15 +56,12 @@ static void sigbus_reraise(siginfo_t *siginfo)
 
     memset(&action, 0, sizeof(action));
     action.sa_handler = SIG_DFL;
-    if (!sigaction(SIGBUS, &action, NULL)) {
-        qtldr_crash_dump_signal(siginfo);
-        raise(SIGBUS);
-        sigemptyset(&set);
-        sigaddset(&set, SIGBUS);
-        pthread_sigmask(SIG_UNBLOCK, &set, NULL);
-    }
-    perror("Failed to re-raise SIGBUS!");
-    abort();
+    assert(sigaction(SIGBUS, &action, NULL) == 0);
+    qtldr_crash_dump_signal(siginfo);
+    raise(SIGBUS);
+    sigemptyset(&set);
+    sigaddset(&set, SIGBUS);
+    pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 }
 
 static void sigbus_handler(int n, siginfo_t *siginfo, void *ctx)
-- 
2.56.0