qtest: Improve error messages when property can not be set right now

When you try to set qtest property "log" while the qtest object is
active, the error message blames "insufficient permission":

    $ qemu-system-x86_64 -S -display none -nodefaults -monitor stdio -chardev socket,id=chrqt0,path=qtest.socket,server=on,wait=off -object qtest,id=qt0,chardev=chrqt0,log=/dev/null
    QEMU 7.1.50 monitor - type 'help' for more information
    (qemu) qom-set /objects/qt0 log qtest.log
    Error: Insufficient permission to perform this operation

This implies it could work with "sufficient permission".  It can't.
Change the error message to:

    Error: Property 'log' can not be set now

Same for property "chardev".

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221012153801.2604340-4-armbru@redhat.com>

diff --git a/softmmu/qtest.c b/softmmu/qtest.c
index f8acef2628d33760906e7b7b890ab67fd8d8f1ba..afea7693d0cd7d5eda066a63b4efeff87be2aeb1 100644 (file)
--- a/softmmu/qtest.c
+++ b/softmmu/qtest.c
@@ -977,7 +977,7 @@ static void qtest_set_log(Object *obj, const char *value, Error **errp)
     QTest *q = QTEST(obj);
 
     if (qtest == q) {
-        error_setg(errp, QERR_PERMISSION_DENIED);
+        error_setg(errp, "Property 'log' can not be set now");
     } else {
         g_free(q->log);
         q->log = g_strdup(value);
@@ -997,7 +997,7 @@ static void qtest_set_chardev(Object *obj, const char *value, Error **errp)
     Chardev *chr;
 
     if (qtest == q) {
-        error_setg(errp, QERR_PERMISSION_DENIED);
+        error_setg(errp, "Property 'chardev' can not be set now");
         return;
     }