Patchwork [07/23] QMP: Fix error reporting in the async API

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Submitter Luiz Capitulino
Date July 1, 2010, 7:21 p.m.
Message ID <1278012111-26227-8-git-send-email-lcapitulino@redhat.com>
Download mbox | patch
Permalink /patch/57575/
State New
Headers show

Comments

Luiz Capitulino - July 1, 2010, 7:21 p.m.
The current asynchronous command API doesn't return a QMP response
when the async command fails.

This is easy to reproduce with the balloon command (the sole async
command we have so far): run qemu w/o the '-balloon virtio' option
and try to issue the balloon command via QMP: no response will be
sent to the client.

This commit fixes the problem by making qmp_async_cmd_handler()
return the handler's error code and then calling
monitor_protocol_emitter() if the handler has returned an error.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
---
 monitor.c |   12 ++++++++----
 1 files changed, 8 insertions(+), 4 deletions(-)

Patch

diff --git a/monitor.c b/monitor.c
index 980e98d..58b060b 100644
--- a/monitor.c
+++ b/monitor.c
@@ -546,10 +546,10 @@  static void qmp_monitor_complete(void *opaque, QObject *ret_data)
     monitor_protocol_emitter(opaque, ret_data);
 }
 
-static void qmp_async_cmd_handler(Monitor *mon, const mon_cmd_t *cmd,
-                                  const QDict *params)
+static int qmp_async_cmd_handler(Monitor *mon, const mon_cmd_t *cmd,
+                                 const QDict *params)
 {
-    cmd->mhandler.cmd_async(mon, params, qmp_monitor_complete, mon);
+    return cmd->mhandler.cmd_async(mon, params, qmp_monitor_complete, mon);
 }
 
 static void qmp_async_info_handler(Monitor *mon, const mon_cmd_t *cmd)
@@ -4239,7 +4239,11 @@  static void handle_qmp_command(JSONMessageParser *parser, QList *tokens)
     }
 
     if (monitor_handler_is_async(cmd)) {
-        qmp_async_cmd_handler(mon, cmd, args);
+        err = qmp_async_cmd_handler(mon, cmd, args);
+        if (err) {
+            /* emit the error response */
+            goto err_out;
+        }
     } else {
         monitor_call_handler(mon, cmd, args);
     }