[PATCH v3 06/35] monitor: add 'chardev' property to Monitor base class

["Daniel P. Berrangé" <berrange@redhat.com>]

This is associates both QMP and HMP monitors with a character
device backend.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 chardev/char.c             |  3 ++-
 gdbstub/system.c           |  4 ++--
 include/monitor/monitor.h  |  4 ++--
 monitor/hmp.c              | 10 ++++++--
 monitor/monitor-internal.h |  2 ++
 monitor/monitor.c          | 47 ++++++++++++++++++++++++++++++--------
 monitor/qmp.c              | 18 ++++++++++-----
 stubs/monitor-internal.c   |  2 +-
 8 files changed, 67 insertions(+), 23 deletions(-)

diff --git a/chardev/char.c b/chardev/char.c
index 813c04d953..981fbb1aaa 100644
--- a/chardev/char.c
+++ b/chardev/char.c
@@ -804,8 +804,9 @@ static Chardev *qemu_chr_new_from_name(const char *label, const char *filename,
     }
 
     if (qemu_opt_get_bool(opts, "mux", 0)) {
+        const char *chardev_id = qemu_opts_id(opts);
         assert(permit_mux_mon);
-        monitor_new_hmp(chr, true, &err);
+        monitor_new_hmp(chardev_id, true, &err);
         if (err) {
             error_report_err(err);
             object_unparent(OBJECT(chr));
diff --git a/gdbstub/system.c b/gdbstub/system.c
index 20dcf7878d..920abda184 100644
--- a/gdbstub/system.c
+++ b/gdbstub/system.c
@@ -386,9 +386,9 @@ bool gdbserver_start(const char *device, Error **errp)
         qemu_add_vm_change_state_handler(gdb_vm_state_change, NULL);
 
         /* Initialize a monitor terminal for gdb */
-        mon_chr = qemu_chardev_new(NULL, TYPE_CHARDEV_GDB,
+        mon_chr = qemu_chardev_new("gdbchrdev0", TYPE_CHARDEV_GDB,
                                    NULL, NULL, &error_abort);
-        monitor_new_hmp(mon_chr, false, &error_abort);
+        monitor_new_hmp("gdbchrdev0", false, &error_abort);
     } else {
         qemu_chr_fe_deinit(&gdbserver_system_state.chr, true);
         mon_chr = gdbserver_system_state.mon_chr;
diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h
index 2e9f9e12e9..a135b3a590 100644
--- a/include/monitor/monitor.h
+++ b/include/monitor/monitor.h
@@ -28,8 +28,8 @@ bool monitor_cur_is_qmp(void);
 
 void monitor_init_globals(void);
 void monitor_init_globals_core(void);
-void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp);
-void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp);
+void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp);
+void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp);
 int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp);
 int monitor_new_opts(QemuOpts *opts, Error **errp);
 void monitor_cleanup(void);
diff --git a/monitor/hmp.c b/monitor/hmp.c
index 81047d2513..4ab81b5904 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -23,6 +23,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qapi/error.h"
 #include <dirent.h>
 #include "hw/core/qdev.h"
 #include "hw/core/sysemu-cpu-ops.h"
@@ -1538,8 +1539,9 @@ static void monitor_readline_flush(void *opaque)
     monitor_flush(&mon->parent_obj);
 }
 
-void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp)
+void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp)
 {
+    ERRP_GUARD();
     MonitorHMP *mon;
     static int counter;
     g_autofree char *id = g_strdup_printf("hmpcompat%d", counter++);
@@ -1547,13 +1549,17 @@ void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp)
                                         object_get_objects_root(),
                                         id,
                                         errp,
+                                        "chardev", chardev_id,
                                         NULL);
+
     if (!obj) {
         return;
     }
+
     mon = MONITOR_HMP(obj);
 
-    if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
+    monitor_complete(MONITOR(mon), errp);
+    if (*errp) {
         object_unparent(OBJECT(mon));
         return;
     }
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index 05c1f2f5e0..145d52fd71 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -108,6 +108,7 @@ struct MonitorClass {
 
 struct Monitor {
     Object parent;
+    char *chardev_id;
     CharFrontend chr;
     int suspend_cnt;            /* Needs to be accessed atomically */
     bool is_qmp;
@@ -192,6 +193,7 @@ extern QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
 extern QemuMutex monitor_lock;
 extern MonitorList mon_list;
 
+void monitor_complete(Monitor *mon, Error **errp);
 void monitor_data_init(Monitor *mon, bool is_qmp, bool skip_flush,
                        bool use_io_thread);
 void monitor_data_destroy(Monitor *mon);
diff --git a/monitor/monitor.c b/monitor/monitor.c
index a497c25c54..747ca27fd5 100644
--- a/monitor/monitor.c
+++ b/monitor/monitor.c
@@ -77,10 +77,31 @@ OBJECT_DEFINE_TYPE(Monitor, monitor, MONITOR, OBJECT);
 
 static void monitor_finalize(Object *obj)
 {
+    Monitor *mon = MONITOR(obj);
+
+    g_free(mon->chardev_id);
+}
+
+static char *monitor_get_chardev_id(Object *obj, Error **errp)
+{
+    Monitor *mon = MONITOR(obj);
+
+    return g_strdup(mon->chardev_id);
+}
+
+static void monitor_set_chardev_id(Object *obj, const char *str, Error **errp)
+{
+    Monitor *mon = MONITOR(obj);
+
+    g_free(mon->chardev_id);
+    mon->chardev_id = g_strdup(str);
 }
 
 static void monitor_class_init(ObjectClass *cls, const void *data)
 {
+    object_class_property_add_str(cls, "chardev",
+                                  monitor_get_chardev_id,
+                                  monitor_set_chardev_id);
 }
 
 static void monitor_init(Object *obj)
@@ -729,16 +750,24 @@ void monitor_init_globals(void)
     aio_co_schedule(iohandler_get_aio_context(), qmp_dispatcher_co);
 }
 
-int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
+void monitor_complete(Monitor *mon, Error **errp)
 {
-    ERRP_GUARD();
-    Chardev *chr;
+    if (mon->chardev_id) {
+        Chardev *chr = qemu_chr_find(mon->chardev_id);
+        if (chr == NULL) {
+            error_setg(errp, "chardev \"%s\" not found", mon->chardev_id);
+            return;
+        }
 
-    chr = qemu_chr_find(opts->chardev);
-    if (chr == NULL) {
-        error_setg(errp, "chardev \"%s\" not found", opts->chardev);
-        return -1;
+        if (!qemu_chr_fe_init(&mon->chr, chr, errp)) {
+            return;
+        }
     }
+}
+
+int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
+{
+    ERRP_GUARD();
 
     if (!opts->has_mode) {
         opts->mode = allow_hmp ? MONITOR_MODE_READLINE : MONITOR_MODE_CONTROL;
@@ -746,7 +775,7 @@ int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
 
     switch (opts->mode) {
     case MONITOR_MODE_CONTROL:
-        monitor_new_qmp(chr, opts->pretty, errp);
+        monitor_new_qmp(opts->chardev, opts->pretty, errp);
         break;
     case MONITOR_MODE_READLINE:
         if (!allow_hmp) {
@@ -757,7 +786,7 @@ int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
             error_setg(errp, "'pretty' is not compatible with HMP monitors");
             return -1;
         }
-        monitor_new_hmp(chr, true, errp);
+        monitor_new_hmp(opts->chardev, true, errp);
         break;
     default:
         g_assert_not_reached();
diff --git a/monitor/qmp.c b/monitor/qmp.c
index 5231ed506a..0abf2677f9 100644
--- a/monitor/qmp.c
+++ b/monitor/qmp.c
@@ -527,8 +527,9 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
     monitor_list_append(&mon->parent_obj);
 }
 
-void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp)
+void monitor_new_qmp(const char *chardev_id, bool pretty, Error **errp)
 {
+    ERRP_GUARD();
     MonitorQMP *mon;
     static int counter;
     g_autofree char *id = g_strdup_printf("qmpcompat%d", counter++);
@@ -536,21 +537,26 @@ void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp)
                                         object_get_objects_root(),
                                         id,
                                         errp,
+                                        "chardev", chardev_id,
                                         NULL);
+
     if (!obj) {
         return;
     }
-    mon = MONITOR_QMP(obj);
 
-    if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
+    mon = MONITOR_QMP(obj);
+    monitor_complete(MONITOR(mon), errp);
+    if (*errp) {
         object_unparent(OBJECT(mon));
         return;
     }
+
     qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
 
     /* Note: we run QMP monitor in I/O thread when @chr supports that */
     monitor_data_init(&mon->parent_obj, true, false,
-                      qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_GCONTEXT));
+                      qemu_chr_has_feature(mon->parent_obj.chr.chr,
+                                           QEMU_CHAR_FEATURE_GCONTEXT));
 
     mon->pretty = pretty;
 
@@ -563,12 +569,12 @@ void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp)
          * Make sure the old iowatch is gone.  It's possible when
          * e.g. the chardev is in client mode, with wait=on.
          */
-        remove_fd_in_watch(chr);
+        remove_fd_in_watch(mon->parent_obj.chr.chr);
         /*
          * Clean up listener IO sources early to prevent racy fd
          * handling between the main thread and the I/O thread.
          */
-        remove_listener_fd_in_watch(chr);
+        remove_listener_fd_in_watch(mon->parent_obj.chr.chr);
         /*
          * We can't call qemu_chr_fe_set_handlers() directly here
          * since chardev might be running in the monitor I/O
diff --git a/stubs/monitor-internal.c b/stubs/monitor-internal.c
index 23d58da184..51db7588b9 100644
--- a/stubs/monitor-internal.c
+++ b/stubs/monitor-internal.c
@@ -8,6 +8,6 @@ int monitor_get_fd(Monitor *mon, const char *name, Error **errp)
     return -1;
 }
 
-void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp)
+void monitor_new_hmp(const char *chardev_id, bool use_readline, Error **errp)
 {
 }
-- 
2.54.0