[PATCH v6 23/25] monitor: start making qmp_human_monitor_command() asynchronous

["Marc-André Lureau" <marcandre.lureau@redhat.com>]

This prepares the work for HMP commands to be asynchronous.

Start making QMP human-monitor-command asynchronous, although
QmpReturn is used synchronously on error or after
handle_hmp_command().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 monitor/misc.c | 14 ++++++++------
 qapi/misc.json |  3 ++-
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/monitor/misc.c b/monitor/misc.c
index bb33ca73cf..3617f855f5 100644
--- a/monitor/misc.c
+++ b/monitor/misc.c
@@ -115,8 +115,8 @@ static QLIST_HEAD(, MonFdset) mon_fdsets;
 
 static HMPCommand hmp_info_cmds[];
 
-char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
-                                int64_t cpu_index, Error **errp)
+void qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
+                               int64_t cpu_index, QmpReturn *qret)
 {
     char *output = NULL;
     Monitor *old_mon;
@@ -130,15 +130,15 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
     if (has_cpu_index) {
         int ret = monitor_set_cpu(cpu_index);
         if (ret < 0) {
-            cur_mon = old_mon;
-            error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cpu-index",
+            Error *err = NULL;
+            error_setg(&err, QERR_INVALID_PARAMETER_VALUE, "cpu-index",
                        "a CPU number");
+            qmp_return_error(qret, err);
             goto out;
         }
     }
 
     handle_hmp_command(&hmp, command_line);
-    cur_mon = old_mon;
 
     qemu_mutex_lock(&hmp.common.mon_lock);
     if (qstring_get_length(hmp.common.outbuf) > 0) {
@@ -148,9 +148,11 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
     }
     qemu_mutex_unlock(&hmp.common.mon_lock);
 
+    qmp_human_monitor_command_return(qret, output);
+
 out:
+    cur_mon = old_mon;
     monitor_data_destroy(&hmp.common);
-    return output;
 }
 
 /**
diff --git a/qapi/misc.json b/qapi/misc.json
index 33b94e3589..15a8bc0d0d 100644
--- a/qapi/misc.json
+++ b/qapi/misc.json
@@ -1054,7 +1054,8 @@
 { 'command': 'human-monitor-command',
   'data': {'command-line': 'str', '*cpu-index': 'int'},
   'returns': 'str',
-  'features': [ 'savevm-monitor-nodes' ] }
+  'features': [ 'savevm-monitor-nodes' ],
+  'async': true }
 
 ##
 # @change:
-- 
2.24.0