net: Move error reporting from net_init_client/netdev to the calling site

It looks strange that net_init_client() and net_init_netdev() both
take an "Error **errp" parameter, but then do the error reporting
with "error_report_err(local_err)" on their own. Let's move the
error reporting to the calling site instead to simplify this code
a little bit.
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>

include/net/net.h

@@ -206,7 +206,7 @@ extern const char *legacy_bootp_filename;
 
 int net_client_init(QemuOpts *opts, bool is_netdev, Error **errp);
 int net_client_parse(QemuOptsList *opts_list, const char *str);
-int net_init_clients(void);
+int net_init_clients(Error **errp);
 void net_check_clients(void);
 void net_cleanup(void);
 void hmp_host_net_add(Monitor *mon, const QDict *qdict);

net/net.c

@@ -1520,46 +1520,27 @@ void net_check_clients(void)
 
 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
 {
-    Error *local_err = NULL;
-
-    net_client_init(opts, false, &local_err);
-    if (local_err) {
-        error_report_err(local_err);
-        return -1;
-    }
-
-    return 0;
+    return net_client_init(opts, false, errp);
 }
 
 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
 {
-    Error *local_err = NULL;
-    int ret;
-
-    ret = net_client_init(opts, true, &local_err);
-    if (local_err) {
-        error_report_err(local_err);
-        return -1;
-    }
-
-    return ret;
+    return net_client_init(opts, true, errp);
 }
 
-int net_init_clients(void)
+int net_init_clients(Error **errp)
 {
-    QemuOptsList *net = qemu_find_opts("net");
-
     net_change_state_entry =
         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
 
     QTAILQ_INIT(&net_clients);
 
     if (qemu_opts_foreach(qemu_find_opts("netdev"),
-                          net_init_netdev, NULL, NULL)) {
+                          net_init_netdev, NULL, errp)) {
         return -1;
     }
 
-    if (qemu_opts_foreach(net, net_init_client, NULL, NULL)) {
+    if (qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL, errp)) {
         return -1;
     }
 

vl.c

@@ -4489,7 +4489,8 @@ int main(int argc, char **argv, char **envp)
 
     colo_info_init();
 
-    if (net_init_clients() < 0) {
+    if (net_init_clients(&err) < 0) {
+        error_report_err(err);
         exit(1);
     }