[Qemu-devel] [PATCH] stop using stdio for monitor/serial/etc with -daemonize

[Michael Tokarev <mjt@tls.msk.ru>]

Current code binds monitor and serial port to the guest console
unless -nographic is specified, which is okay.  But when there's
no guest console (-nographic), the code tries to use stdio for
the same default devices.  But it does not check for -daemonize
at the same time -- because when -daemonize is given, there's no
point at using stdin since it will be closed down the line.
However, when serial port is attached to stdin, tty control
modes are changed (switching tty to raw mode), and qemu will
switch to background, leaving the tty in bad state.

Take -daemonize into account too, when assigning default devices,
and for -nographic -daemonize case, assign them to "null" instead.

This is https://bugs.launchpad.net/qemu/+bug/1024275
or http://bugs.debian.org/549195 .

This patch depends on another patch, 995ee2bf469de6,
"curses: don't initialize curses when qemu is daemonized",
by Hitoshi Mitake, which creates is_daemonized() routine.

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
---
 vl.c |   23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/vl.c b/vl.c
index 48049ef..ae1794f 100644
--- a/vl.c
+++ b/vl.c
@@ -3395,17 +3395,26 @@ int main(int argc, char **argv, char **envp)
     if (display_type == DT_NOGRAPHIC) {
         if (default_parallel)
             add_device_config(DEV_PARALLEL, "null");
-        if (default_serial && default_monitor) {
-            add_device_config(DEV_SERIAL, "mon:stdio");
-        } else if (default_virtcon && default_monitor) {
-            add_device_config(DEV_VIRTCON, "mon:stdio");
+        if (!is_daemonized()) {
+            if (default_serial && default_monitor) {
+                add_device_config(DEV_SERIAL, "mon:stdio");
+            } else if (default_virtcon && default_monitor) {
+                add_device_config(DEV_VIRTCON, "mon:stdio");
+            } else {
+                if (default_serial)
+                    add_device_config(DEV_SERIAL, "stdio");
+                if (default_virtcon)
+                    add_device_config(DEV_VIRTCON, "stdio");
+                if (default_monitor)
+                    monitor_parse("stdio", "readline");
+            }
         } else {
             if (default_serial)
-                add_device_config(DEV_SERIAL, "stdio");
+                add_device_config(DEV_SERIAL, "null");
             if (default_virtcon)
-                add_device_config(DEV_VIRTCON, "stdio");
+                add_device_config(DEV_VIRTCON, "null");
             if (default_monitor)
-                monitor_parse("stdio", "readline");
+                monitor_parse("stdio", "null");
         }
     } else {
         if (default_serial)
-- 
1.7.10.4