monitor: introduce HumanReadableText and HMP support

This provides a foundation on which to convert simple HMP commands to
use QMP. The QMP implementation will generate formatted text targeted
for human consumption, returning it in the HumanReadableText data type.

The HMP command handler will simply print out the formatted string
within the HumanReadableText data type. Since this will be an entirely
formulaic action in the case of HMP commands taking no arguments, a
custom command handler is provided.

Thus instead of registering a 'cmd' callback for the HMP command, a
'cmd_info_hrt' callback is provided, which will simply be a pointer
to the QMP implementation.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

1 files changed, 17 insertions, 1 deletions

diff --git a/monitor/misc.c b/monitor/misc.c
index c2d227a07c..0e124044d0 100644
--- a/monitor/misc.c
+++ b/monitor/misc.c
@@ -1964,7 +1964,7 @@ void monitor_register_hmp(const char *name, bool info,
 
     while (table->name != NULL) {
         if (strcmp(table->name, name) == 0) {
-            g_assert(table->cmd == NULL);
+            g_assert(table->cmd == NULL && table->cmd_info_hrt == NULL);
             table->cmd = cmd;
             return;
         }
@@ -1973,6 +1973,22 @@ void monitor_register_hmp(const char *name, bool info,
     g_assert_not_reached();
 }
 
+void monitor_register_hmp_info_hrt(const char *name,
+                                   HumanReadableText *(*handler)(Error **errp))
+{
+    HMPCommand *table = hmp_info_cmds;
+
+    while (table->name != NULL) {
+        if (strcmp(table->name, name) == 0) {
+            g_assert(table->cmd == NULL && table->cmd_info_hrt == NULL);
+            table->cmd_info_hrt = handler;
+            return;
+        }
+        table++;
+    }
+    g_assert_not_reached();
+}
+
 void monitor_init_globals(void)
 {
     monitor_init_globals_core();