log: Make glib logging go through QEMU

This commit adds a error_init() helper which calls
g_log_set_default_handler() so that glib logs (g_log, g_warning, ...)
are handled similarly to other QEMU logs. This means they will get a
timestamp if timestamps are enabled, and they will go through the
HMP monitor if one is configured.

This commit also adds a call to error_init() to the binaries
installed by QEMU. Since error_init() also calls error_set_progname(),
this means that *-linux-user, *-bsd-user and qemu-pr-helper messages
output with error_report, info_report, ... will slightly change: they
will be prefixed by the binary name.

glib debug messages are enabled through G_MESSAGES_DEBUG similarly to
the glib default log handler.

At the moment, this change will mostly impact SPICE logging if your
spice version is >= 0.14.1. With older spice versions, this is not going
to work as expected, but will not have any ill effect, so this call is
not conditional on the SPICE version.

Signed-off-by: Christophe Fergeau <cfergeau@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20190131164614.19209-3-cfergeau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/scsi/qemu-pr-helper.c b/scsi/qemu-pr-helper.c
index e7af637232..2541fbbd1b 100644
--- a/scsi/qemu-pr-helper.c
+++ b/scsi/qemu-pr-helper.c
@@ -895,6 +895,7 @@ int main(int argc, char **argv)
 
     signal(SIGPIPE, SIG_IGN);
 
+    error_init(argv[0]);
     module_call_init(MODULE_INIT_TRACE);
     module_call_init(MODULE_INIT_QOM);
     qemu_add_opts(&qemu_trace_opts);