[PATCH v2 3/3] monitor: allow VNC related QMP and HMP commands to take a display ID

[Stefan Reiter <s.reiter@proxmox.com>]

It is possible to specify more than one VNC server on the command line,
either with an explicit ID or the auto-generated ones à la "default",
"vnc2", "vnc3", ...

It is not possible to change the password on one of these extra VNC
displays though. Fix this by adding a "display" parameter to the
"set_password" and "expire_password" QMP and HMP commands.

For HMP, the display is specified using the "-d" value flag.

Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
---
 hmp-commands.hx    | 29 +++++++++++++++--------------
 monitor/hmp-cmds.c |  7 +++++--
 monitor/qmp-cmds.c |  9 +++++----
 qapi/ui.json       | 12 ++++++++++--
 4 files changed, 35 insertions(+), 22 deletions(-)

diff --git a/hmp-commands.hx b/hmp-commands.hx
index 8e45bce2cd..d78e4cfc47 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -1514,34 +1514,35 @@ ERST
 
     {
         .name       = "set_password",
-        .args_type  = "protocol:s,password:s,connected:s?",
-        .params     = "protocol password action-if-connected",
+        .args_type  = "protocol:s,password:s,display:-dS,connected:s?",
+        .params     = "protocol password [-d display] [action-if-connected]",
         .help       = "set spice/vnc password",
         .cmd        = hmp_set_password,
     },
 
 SRST
-``set_password [ vnc | spice ] password [ action-if-connected ]``
-  Change spice/vnc password.  Use zero to make the password stay valid
-  forever.  *action-if-connected* specifies what should happen in
-  case a connection is established: *fail* makes the password change
-  fail.  *disconnect* changes the password and disconnects the
-  client.  *keep* changes the password and keeps the connection up.
-  *keep* is the default.
+``set_password [ vnc | spice ] password [ -d display ] [ action-if-connected ]``
+  Change spice/vnc password.  *display* can be used with 'vnc' to specify
+  which display to set the password on.  *action-if-connected* specifies
+  what should happen in case a connection is established: *fail* makes
+  the password change fail.  *disconnect* changes the password and
+  disconnects the client.  *keep* changes the password and keeps the
+  connection up.  *keep* is the default.
 ERST
 
     {
         .name       = "expire_password",
-        .args_type  = "protocol:s,time:s",
-        .params     = "protocol time",
+        .args_type  = "protocol:s,time:s,display:-dS",
+        .params     = "protocol time [-d display]",
         .help       = "set spice/vnc password expire-time",
         .cmd        = hmp_expire_password,
     },
 
 SRST
-``expire_password [ vnc | spice ]`` *expire-time*
-  Specify when a password for spice/vnc becomes
-  invalid. *expire-time* accepts:
+``expire_password [ vnc | spice ] expire-time [ -d display ]``
+  Specify when a password for spice/vnc becomes invalid.
+  *display* behaves the same as in ``set_password``.
+  *expire-time* accepts:
 
   ``now``
     Invalidate password instantly.
diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
index a7e197a90b..168ca62371 100644
--- a/monitor/hmp-cmds.c
+++ b/monitor/hmp-cmds.c
@@ -1451,10 +1451,12 @@ void hmp_set_password(Monitor *mon, const QDict *qdict)
 {
     const char *protocol  = qdict_get_str(qdict, "protocol");
     const char *password  = qdict_get_str(qdict, "password");
+    const char *display = qdict_get_try_str(qdict, "display");
     const char *connected = qdict_get_try_str(qdict, "connected");
     Error *err = NULL;
 
-    qmp_set_password(protocol, password, !!connected, connected, &err);
+    qmp_set_password(protocol, password, !!connected, connected, !!display,
+                     display, &err);
     hmp_handle_error(mon, err);
 }
 
@@ -1462,9 +1464,10 @@ void hmp_expire_password(Monitor *mon, const QDict *qdict)
 {
     const char *protocol  = qdict_get_str(qdict, "protocol");
     const char *whenstr = qdict_get_str(qdict, "time");
+    const char *display = qdict_get_try_str(qdict, "display");
     Error *err = NULL;
 
-    qmp_expire_password(protocol, whenstr, &err);
+    qmp_expire_password(protocol, whenstr, !!display, display, &err);
     hmp_handle_error(mon, err);
 }
 
diff --git a/monitor/qmp-cmds.c b/monitor/qmp-cmds.c
index 5c0d5e116b..b53869d10c 100644
--- a/monitor/qmp-cmds.c
+++ b/monitor/qmp-cmds.c
@@ -164,7 +164,8 @@ void qmp_system_wakeup(Error **errp)
 }
 
 void qmp_set_password(const char *protocol, const char *password,
-                      bool has_connected, const char *connected, Error **errp)
+                      bool has_connected, const char *connected,
+                      bool has_display, const char *display, Error **errp)
 {
     int disconnect_if_connected = 0;
     int fail_if_connected = 0;
@@ -197,7 +198,7 @@ void qmp_set_password(const char *protocol, const char *password,
         }
         /* Note that setting an empty password will not disable login through
          * this interface. */
-        rc = vnc_display_password(NULL, password);
+        rc = vnc_display_password(has_display ? display : NULL, password);
     } else {
         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "protocol",
                    "'vnc' or 'spice'");
@@ -210,7 +211,7 @@ void qmp_set_password(const char *protocol, const char *password,
 }
 
 void qmp_expire_password(const char *protocol, const char *whenstr,
-                         Error **errp)
+                         bool has_display, const char *display, Error **errp)
 {
     time_t when;
     int rc;
@@ -231,7 +232,7 @@ void qmp_expire_password(const char *protocol, const char *whenstr,
         }
         rc = qemu_spice.set_pw_expire(when);
     } else if (strcmp(protocol, "vnc") == 0) {
-        rc = vnc_display_pw_expire(NULL, when);
+        rc = vnc_display_pw_expire(has_display ? display : NULL, when);
     } else {
         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "protocol",
                    "'vnc' or 'spice'");
diff --git a/qapi/ui.json b/qapi/ui.json
index b2cf7a6759..fa84df9a70 100644
--- a/qapi/ui.json
+++ b/qapi/ui.json
@@ -25,6 +25,9 @@
 #             'disconnect' to disconnect existing clients
 #             'keep' to maintain existing clients
 #
+# @display: In case of VNC, the id of the display where the password
+#           should be changed. Defaults to the first.
+#
 # Returns: - Nothing on success
 #          - If Spice is not enabled, DeviceNotFound
 #
@@ -38,7 +41,8 @@
 #
 ##
 { 'command': 'set_password',
-  'data': {'protocol': 'str', 'password': 'str', '*connected': 'str'} }
+  'data': {'protocol': 'str', 'password': 'str', '*connected': 'str',
+           '*display': 'str'} }
 
 ##
 # @expire_password:
@@ -54,6 +58,9 @@
 #        - '+INT' where INT is the number of seconds from now (integer)
 #        - 'INT' where INT is the absolute time in seconds
 #
+# @display: In case of VNC, the id of the display where the password
+#           should be set to expire. Defaults to the first.
+#
 # Returns: - Nothing on success
 #          - If @protocol is 'spice' and Spice is not active, DeviceNotFound
 #
@@ -71,7 +78,8 @@
 # <- { "return": {} }
 #
 ##
-{ 'command': 'expire_password', 'data': {'protocol': 'str', 'time': 'str'} }
+{ 'command': 'expire_password',
+  'data': {'protocol': 'str', 'time': 'str', '*display': 'str'} }
 
 ##
 # @screendump:
-- 
2.30.2