This series adds qemu-vnc, a standalone VNC server that connects to a
running QEMU instance via the D-Bus display interface (org.qemu.Display1).
This allows serving a VNC display as a separate process with an independent
lifecycle and privilege domain, without requiring VNC support compiled into
the QEMU system emulator itself.

The bulk of the series is preparatory refactoring:

- Clean up VNC code: merge init/open, fix leaks, simplify error handling
- Extract and clean up VT100 emulation from console-vc into a reusable unit
- Reorganize ui/ code: move DisplaySurface functions, vgafont, datadir
and other pieces into their own files
- Refactor console APIs: rename methods, simplify listener registration,
return completion status from gfx_update
- Extract common ui sources into a static library that can be linked by
both the system emulator and the new standalone binary

The final patch adds contrib/qemu-vnc, built when both VNC and D-Bus
display support are enabled.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
Marc-André Lureau (60):
      ui/vnc-jobs: fix VncRectEntry leak on job cleanup
      ui/vnc-jobs: clear source tag
      ui/vnc-jobs: remove needless buffer_reset() before end
      ui/vnc: clarify intent using buffer_empty() function
      ui/vnc-jobs: vnc_has_job_locked() argument cannot be NULL
      ui/vnc-jobs: remove dead VncJobQueue.exit
      ui/vnc-jobs: remove vnc_queue_clear()
      ui/vnc-jobs: narrow taking the lock when pushing empty jobs
      ui/vnc-jobs: drop redundant (and needless) qemu_thread_get_self()
      ui/console-vc: fix off-by-one in CSI J 2 (clear entire screen)
      ui/console-vc: add UTF-8 input decoding with CP437 rendering
      ui/console-vc: ignore string-type escape sequences
      ui/console-vc: fix comment shift-out/in comments
      ui/console: dispatch get_label() through QOM virtual method
      ui/console-vc: introduce QemuVT100
      ui/console-vc: set vt100 associated pixman image
      ui/console-vc: vga_putcharxy()->vt100_putcharxy()
      ui/console-vc: make invalidate_xy() take vt100
      ui/console-vc: make show_cursor() take vt100
      ui/console-vc: decouple VT100 display updates via function pointer
      ui/console-vc: console_refresh() -> vt100_refresh()
      ui/console-vc: move cursor blinking logic into VT100 layer
      ui/console-vc: console_scroll() -> vt100_scroll()
      ui/console-vc: refactor text_console_resize() into vt100_set_image()
      ui/console-vc: move vc_put_lf() to VT100 layer as vt100_put_lf()
      ui/console-vc: unify the write path
      ui/console-vc: move VT100 state machine and output FIFO into QemuVT100
      ui/console-vc: extract vt100_input() from vc_chr_write()
      ui/console-vc: extract vt100_keysym() from qemu_text_console_handle_keysym()
      ui/console-vc: extract vt100_init() and vt100_fini()
      ui/console: remove console_ch_t typedef and console_write_ch()
      ui: avoid duplicating vgafont16 in each translation unit
      ui/vgafont: add SPDX license header
      ui: move FONT_WIDTH/HEIGHT to vgafont.h
      ui/console-vc: move VT100 emulation into separate unit
      util: move datadir.c from system/
      ui: move DisplaySurface functions to display-surface.c
      ui: make qemu_default_pixelformat() static inline
      ui: make unregister_displaychangelistener() skip unregistered
      ui: minor code simplification
      system: make qemu_del_vm_change_state_handler accept NULL
      ui/vnc: assert preconditions instead of silently returning
      ui/vnc: simplify vnc_init_func error handling
      ui/vnc: VncDisplay.id is not const
      ui/vnc: fix vnc_display_init() leak on failure
      ui/vnc: merge vnc_display_init() and vnc_display_open()
      ui/vnc: report an error for duplicate display id
      ui/vnc: defer listener registration until the console is known
      ui/vnc: explicitly link with png
      ui/vnc: add vnc-system unit, to allow different implementations
      ui/console: remove qemu_console_is_visible()
      ui/console: simplify registering display/console change listener
      ui/console: return completion status from gfx_update callback
      ui/console: rename public API to use consistent qemu_console_ prefix
      ui/console: move console_handle_touch_event() to input
      ui: extract common sources into a static library
      tests: rename the dbus-daemon helper script
      tests/qtest: fix dbus-vmstate-test compilation
      tests/qtest: drop DBUS_VMSTATE_TEST_TMPDIR
      contrib/qemu-vnc: add standalone VNC server over D-Bus

 MAINTAINERS                                      |    5 +
 docs/conf.py                                     |    3 +
 docs/interop/dbus-display.rst                    |    2 +
 docs/interop/dbus-vnc.rst                        |   26 +
 docs/interop/index.rst                           |    1 +
 docs/meson.build                                 |    1 +
 docs/tools/index.rst                             |    1 +
 docs/tools/qemu-vnc.rst                          |  199 +
 meson.build                                      |   17 +
 contrib/qemu-vnc/qemu-vnc.h                      |   46 +
 contrib/qemu-vnc/trace.h                         |    4 +
 hw/display/qxl.h                                 |    2 +-
 include/ui/console.h                             |  146 +-
 include/ui/input.h                               |   15 +
 include/ui/qemu-pixman.h                         |    8 +
 include/ui/surface.h                             |    2 -
 ui/console-priv.h                                |    8 -
 ui/cp437.h                                       |   13 +
 ui/keymaps.h                                     |    1 +
 ui/vgafont.h                                     | 4618 +---------------------
 ui/vnc.h                                         |    9 +-
 ui/vt100.h                                       |   92 +
 contrib/qemu-vnc/audio.c                         |  307 ++
 contrib/qemu-vnc/chardev.c                       |  127 +
 contrib/qemu-vnc/clipboard.c                     |  378 ++
 contrib/qemu-vnc/console.c                       |  168 +
 contrib/qemu-vnc/dbus.c                          |  439 ++
 contrib/qemu-vnc/display.c                       |  456 +++
 contrib/qemu-vnc/input.c                         |  239 ++
 contrib/qemu-vnc/qemu-vnc.c                      |  450 +++
 contrib/qemu-vnc/stubs.c                         |   66 +
 contrib/qemu-vnc/utils.c                         |   59 +
 hw/arm/musicpal.c                                |    7 +-
 hw/display/artist.c                              |    8 +-
 hw/display/ati.c                                 |   16 +-
 hw/display/bcm2835_fb.c                          |   12 +-
 hw/display/bochs-display.c                       |   20 +-
 hw/display/cg3.c                                 |   11 +-
 hw/display/cirrus_vga.c                          |    8 +-
 hw/display/cirrus_vga_isa.c                      |    2 +-
 hw/display/dm163.c                               |   10 +-
 hw/display/exynos4210_fimd.c                     |   10 +-
 hw/display/g364fb.c                              |   19 +-
 hw/display/jazz_led.c                            |   24 +-
 hw/display/macfb.c                               |   12 +-
 hw/display/next-fb.c                             |    8 +-
 hw/display/omap_lcdc.c                           |   18 +-
 hw/display/pl110.c                               |    9 +-
 hw/display/qxl-render.c                          |   18 +-
 hw/display/qxl.c                                 |   25 +-
 hw/display/ramfb-standalone.c                    |    6 +-
 hw/display/ramfb.c                               |    4 +-
 hw/display/sm501.c                               |   14 +-
 hw/display/ssd0303.c                             |   14 +-
 hw/display/ssd0323.c                             |   16 +-
 hw/display/tcx.c                                 |   22 +-
 hw/display/vga-isa.c                             |    2 +-
 hw/display/vga-mmio.c                            |    2 +-
 hw/display/vga-pci.c                             |    6 +-
 hw/display/vga.c                                 |   60 +-
 hw/display/vhost-user-gpu.c                      |   22 +-
 hw/display/virtio-gpu-base.c                     |    7 +-
 hw/display/virtio-gpu-rutabaga.c                 |   10 +-
 hw/display/virtio-gpu-udmabuf.c                  |    4 +-
 hw/display/virtio-gpu-virgl.c                    |   20 +-
 hw/display/virtio-gpu.c                          |   26 +-
 hw/display/virtio-vga.c                          |   10 +-
 hw/display/vmware_vga.c                          |   21 +-
 hw/display/xenfb.c                               |   12 +-
 hw/display/xlnx_dp.c                             |   20 +-
 hw/vfio/display.c                                |   49 +-
 system/runstate.c                                |    3 +
 tests/qtest/dbus-vmstate-test.c                  |   13 +-
 tests/qtest/dbus-vnc-test.c                      |  733 ++++
 ui/console-vc-stubs.c                            |    9 +-
 ui/console-vc.c                                  | 1021 +----
 ui/console.c                                     |  471 +--
 ui/cp437.c                                       |  205 +
 ui/curses.c                                      |   23 +-
 ui/dbus-console.c                                |   16 +-
 ui/dbus-listener.c                               |   37 +-
 ui/display-surface.c                             |  107 +
 ui/egl-headless.c                                |    8 +-
 ui/gtk-egl.c                                     |    6 +-
 ui/gtk-gl-area.c                                 |    6 +-
 ui/gtk.c                                         |   36 +-
 ui/input.c                                       |   65 +
 ui/keymaps.c                                     |   13 +-
 ui/sdl2-2d.c                                     |    2 +-
 ui/sdl2-gl.c                                     |    2 +-
 ui/sdl2.c                                        |   24 +-
 ui/spice-display.c                               |   24 +-
 ui/vgafont.c                                     | 4616 +++++++++++++++++++++
 ui/vnc-jobs.c                                    |   54 +-
 ui/vnc-system.c                                  |   19 +
 ui/vnc.c                                         |  202 +-
 ui/vt100.c                                       |  987 +++++
 {system => util}/datadir.c                       |    0
 contrib/qemu-vnc/meson.build                     |   26 +
 contrib/qemu-vnc/qemu-vnc1.xml                   |  174 +
 contrib/qemu-vnc/trace-events                    |   20 +
 hw/display/apple-gfx.m                           |   26 +-
 meson_options.txt                                |    2 +
 scripts/meson-buildoptions.sh                    |    3 +
 system/meson.build                               |    1 -
 system/trace-events                              |    1 -
 tests/{dbus-vmstate-daemon.sh => dbus-daemon.sh} |   16 +-
 tests/qtest/meson.build                          |   13 +-
 ui/cocoa.m                                       |   23 +-
 ui/meson.build                                   |  103 +-
 util/meson.build                                 |    1 +
 util/trace-events                                |    3 +
 112 files changed, 10982 insertions(+), 6624 deletions(-)
---
base-commit: 559919ce54927d59b215a4665eda7ab6118a48aa
change-id: 20260312-qemu-vnc-9662fc572262

Best regards,
-- 
Marc-André Lureau <marcandre.lureau@redhat.com>

On Tue, Mar 17, 2026 at 12:50:14PM +0400, Marc-André Lureau wrote:
> This series adds qemu-vnc, a standalone VNC server that connects to a
> running QEMU instance via the D-Bus display interface (org.qemu.Display1).
> This allows serving a VNC display as a separate process with an independent
> lifecycle and privilege domain, without requiring VNC support compiled into
> the QEMU system emulator itself.
> 
> The bulk of the series is preparatory refactoring:

A few of the patches in this series are addressing bugs such as the
leaks. Where practical those should probably be ordered at the very
start of the series such that they have minimal deps and could be
cherry-picked to stable.

> 
> - Clean up VNC code: merge init/open, fix leaks, simplify error handling
> - Extract and clean up VT100 emulation from console-vc into a reusable unit
> - Reorganize ui/ code: move DisplaySurface functions, vgafont, datadir
> and other pieces into their own files
> - Refactor console APIs: rename methods, simplify listener registration,
> return completion status from gfx_update
> - Extract common ui sources into a static library that can be linked by
> both the system emulator and the new standalone binary
> 
> The final patch adds contrib/qemu-vnc, built when both VNC and D-Bus
> display support are enabled.
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
> Marc-André Lureau (60):
>       ui/vnc-jobs: fix VncRectEntry leak on job cleanup
>       ui/vnc-jobs: clear source tag
>       ui/vnc-jobs: remove needless buffer_reset() before end
>       ui/vnc: clarify intent using buffer_empty() function
>       ui/vnc-jobs: vnc_has_job_locked() argument cannot be NULL
>       ui/vnc-jobs: remove dead VncJobQueue.exit
>       ui/vnc-jobs: remove vnc_queue_clear()
>       ui/vnc-jobs: narrow taking the lock when pushing empty jobs
>       ui/vnc-jobs: drop redundant (and needless) qemu_thread_get_self()
>       ui/console-vc: fix off-by-one in CSI J 2 (clear entire screen)
>       ui/console-vc: add UTF-8 input decoding with CP437 rendering
>       ui/console-vc: ignore string-type escape sequences
>       ui/console-vc: fix comment shift-out/in comments
>       ui/console: dispatch get_label() through QOM virtual method
>       ui/console-vc: introduce QemuVT100
>       ui/console-vc: set vt100 associated pixman image
>       ui/console-vc: vga_putcharxy()->vt100_putcharxy()
>       ui/console-vc: make invalidate_xy() take vt100
>       ui/console-vc: make show_cursor() take vt100
>       ui/console-vc: decouple VT100 display updates via function pointer
>       ui/console-vc: console_refresh() -> vt100_refresh()
>       ui/console-vc: move cursor blinking logic into VT100 layer
>       ui/console-vc: console_scroll() -> vt100_scroll()
>       ui/console-vc: refactor text_console_resize() into vt100_set_image()
>       ui/console-vc: move vc_put_lf() to VT100 layer as vt100_put_lf()
>       ui/console-vc: unify the write path
>       ui/console-vc: move VT100 state machine and output FIFO into QemuVT100
>       ui/console-vc: extract vt100_input() from vc_chr_write()
>       ui/console-vc: extract vt100_keysym() from qemu_text_console_handle_keysym()
>       ui/console-vc: extract vt100_init() and vt100_fini()
>       ui/console: remove console_ch_t typedef and console_write_ch()
>       ui: avoid duplicating vgafont16 in each translation unit
>       ui/vgafont: add SPDX license header
>       ui: move FONT_WIDTH/HEIGHT to vgafont.h
>       ui/console-vc: move VT100 emulation into separate unit
>       util: move datadir.c from system/
>       ui: move DisplaySurface functions to display-surface.c
>       ui: make qemu_default_pixelformat() static inline
>       ui: make unregister_displaychangelistener() skip unregistered
>       ui: minor code simplification
>       system: make qemu_del_vm_change_state_handler accept NULL
>       ui/vnc: assert preconditions instead of silently returning
>       ui/vnc: simplify vnc_init_func error handling
>       ui/vnc: VncDisplay.id is not const
>       ui/vnc: fix vnc_display_init() leak on failure
>       ui/vnc: merge vnc_display_init() and vnc_display_open()
>       ui/vnc: report an error for duplicate display id
>       ui/vnc: defer listener registration until the console is known
>       ui/vnc: explicitly link with png
>       ui/vnc: add vnc-system unit, to allow different implementations
>       ui/console: remove qemu_console_is_visible()
>       ui/console: simplify registering display/console change listener
>       ui/console: return completion status from gfx_update callback
>       ui/console: rename public API to use consistent qemu_console_ prefix
>       ui/console: move console_handle_touch_event() to input
>       ui: extract common sources into a static library
>       tests: rename the dbus-daemon helper script
>       tests/qtest: fix dbus-vmstate-test compilation
>       tests/qtest: drop DBUS_VMSTATE_TEST_TMPDIR
>       contrib/qemu-vnc: add standalone VNC server over D-Bus
> 
>  MAINTAINERS                                      |    5 +
>  docs/conf.py                                     |    3 +
>  docs/interop/dbus-display.rst                    |    2 +
>  docs/interop/dbus-vnc.rst                        |   26 +
>  docs/interop/index.rst                           |    1 +
>  docs/meson.build                                 |    1 +
>  docs/tools/index.rst                             |    1 +
>  docs/tools/qemu-vnc.rst                          |  199 +
>  meson.build                                      |   17 +
>  contrib/qemu-vnc/qemu-vnc.h                      |   46 +
>  contrib/qemu-vnc/trace.h                         |    4 +
>  hw/display/qxl.h                                 |    2 +-
>  include/ui/console.h                             |  146 +-
>  include/ui/input.h                               |   15 +
>  include/ui/qemu-pixman.h                         |    8 +
>  include/ui/surface.h                             |    2 -
>  ui/console-priv.h                                |    8 -
>  ui/cp437.h                                       |   13 +
>  ui/keymaps.h                                     |    1 +
>  ui/vgafont.h                                     | 4618 +---------------------
>  ui/vnc.h                                         |    9 +-
>  ui/vt100.h                                       |   92 +
>  contrib/qemu-vnc/audio.c                         |  307 ++
>  contrib/qemu-vnc/chardev.c                       |  127 +
>  contrib/qemu-vnc/clipboard.c                     |  378 ++
>  contrib/qemu-vnc/console.c                       |  168 +
>  contrib/qemu-vnc/dbus.c                          |  439 ++
>  contrib/qemu-vnc/display.c                       |  456 +++
>  contrib/qemu-vnc/input.c                         |  239 ++
>  contrib/qemu-vnc/qemu-vnc.c                      |  450 +++
>  contrib/qemu-vnc/stubs.c                         |   66 +
>  contrib/qemu-vnc/utils.c                         |   59 +
>  hw/arm/musicpal.c                                |    7 +-
>  hw/display/artist.c                              |    8 +-
>  hw/display/ati.c                                 |   16 +-
>  hw/display/bcm2835_fb.c                          |   12 +-
>  hw/display/bochs-display.c                       |   20 +-
>  hw/display/cg3.c                                 |   11 +-
>  hw/display/cirrus_vga.c                          |    8 +-
>  hw/display/cirrus_vga_isa.c                      |    2 +-
>  hw/display/dm163.c                               |   10 +-
>  hw/display/exynos4210_fimd.c                     |   10 +-
>  hw/display/g364fb.c                              |   19 +-
>  hw/display/jazz_led.c                            |   24 +-
>  hw/display/macfb.c                               |   12 +-
>  hw/display/next-fb.c                             |    8 +-
>  hw/display/omap_lcdc.c                           |   18 +-
>  hw/display/pl110.c                               |    9 +-
>  hw/display/qxl-render.c                          |   18 +-
>  hw/display/qxl.c                                 |   25 +-
>  hw/display/ramfb-standalone.c                    |    6 +-
>  hw/display/ramfb.c                               |    4 +-
>  hw/display/sm501.c                               |   14 +-
>  hw/display/ssd0303.c                             |   14 +-
>  hw/display/ssd0323.c                             |   16 +-
>  hw/display/tcx.c                                 |   22 +-
>  hw/display/vga-isa.c                             |    2 +-
>  hw/display/vga-mmio.c                            |    2 +-
>  hw/display/vga-pci.c                             |    6 +-
>  hw/display/vga.c                                 |   60 +-
>  hw/display/vhost-user-gpu.c                      |   22 +-
>  hw/display/virtio-gpu-base.c                     |    7 +-
>  hw/display/virtio-gpu-rutabaga.c                 |   10 +-
>  hw/display/virtio-gpu-udmabuf.c                  |    4 +-
>  hw/display/virtio-gpu-virgl.c                    |   20 +-
>  hw/display/virtio-gpu.c                          |   26 +-
>  hw/display/virtio-vga.c                          |   10 +-
>  hw/display/vmware_vga.c                          |   21 +-
>  hw/display/xenfb.c                               |   12 +-
>  hw/display/xlnx_dp.c                             |   20 +-
>  hw/vfio/display.c                                |   49 +-
>  system/runstate.c                                |    3 +
>  tests/qtest/dbus-vmstate-test.c                  |   13 +-
>  tests/qtest/dbus-vnc-test.c                      |  733 ++++
>  ui/console-vc-stubs.c                            |    9 +-
>  ui/console-vc.c                                  | 1021 +----
>  ui/console.c                                     |  471 +--
>  ui/cp437.c                                       |  205 +
>  ui/curses.c                                      |   23 +-
>  ui/dbus-console.c                                |   16 +-
>  ui/dbus-listener.c                               |   37 +-
>  ui/display-surface.c                             |  107 +
>  ui/egl-headless.c                                |    8 +-
>  ui/gtk-egl.c                                     |    6 +-
>  ui/gtk-gl-area.c                                 |    6 +-
>  ui/gtk.c                                         |   36 +-
>  ui/input.c                                       |   65 +
>  ui/keymaps.c                                     |   13 +-
>  ui/sdl2-2d.c                                     |    2 +-
>  ui/sdl2-gl.c                                     |    2 +-
>  ui/sdl2.c                                        |   24 +-
>  ui/spice-display.c                               |   24 +-
>  ui/vgafont.c                                     | 4616 +++++++++++++++++++++
>  ui/vnc-jobs.c                                    |   54 +-
>  ui/vnc-system.c                                  |   19 +
>  ui/vnc.c                                         |  202 +-
>  ui/vt100.c                                       |  987 +++++
>  {system => util}/datadir.c                       |    0
>  contrib/qemu-vnc/meson.build                     |   26 +
>  contrib/qemu-vnc/qemu-vnc1.xml                   |  174 +
>  contrib/qemu-vnc/trace-events                    |   20 +
>  hw/display/apple-gfx.m                           |   26 +-
>  meson_options.txt                                |    2 +
>  scripts/meson-buildoptions.sh                    |    3 +
>  system/meson.build                               |    1 -
>  system/trace-events                              |    1 -
>  tests/{dbus-vmstate-daemon.sh => dbus-daemon.sh} |   16 +-
>  tests/qtest/meson.build                          |   13 +-
>  ui/cocoa.m                                       |   23 +-
>  ui/meson.build                                   |  103 +-
>  util/meson.build                                 |    1 +
>  util/trace-events                                |    3 +
>  112 files changed, 10982 insertions(+), 6624 deletions(-)
> ---
> base-commit: 559919ce54927d59b215a4665eda7ab6118a48aa
> change-id: 20260312-qemu-vnc-9662fc572262
> 
> Best regards,
> -- 
> Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> 

With regards,
Daniel
-- 
|: https://berrange.com       ~~        https://hachyderm.io/@berrange :|
|: https://libvirt.org          ~~          https://entangle-photo.org :|
|: https://pixelfed.art/berrange   ~~    https://fstop138.berrange.com :|