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>
---
Changes in v2:
- renamed utf8_ DFA function/symbols with bh_ (Bjoern Hoehrmann) prefix
- use "QemuVT *vt = &s->vt;" to avoid some code churn
- use size_t for vt100_input()
- replace back compound literal usage for QEMUUIInfo, use variable
- add a preliminary patch to convert vnc_display_init/open() to return bool
- add doc comment for qemu_console_{un}register_listener()
- document GraphicsHwOps.gfx_update better
- add "ui/vnc: make the worker thread per-VncDisplay", and free it on vnc_display_free()
- add "ui/vnc: add vnc_cleanup()"
- add "replace VNC_DEBUG with trace-events"
- qemu-vnc: add sasl & authz support, doc updates
- move qemu-vnc under tools/
- rebased, collect trailer tags
- Link to v1: https://lore.kernel.org/qemu-devel/20260317-qemu-vnc-v1-0-48eb1dcf7b76@redhat.com

---
Marc-André Lureau (67):
      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 queue lock
      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/keymaps: introduce kbd_layout_free()
      ui/vnc: fix vnc_display_init() leak on failure
      ui/vnc: make vnc_disconnect_finish() private
      ui/vnc: make the worker thread per-VncDisplay
      ui/vnc: vnc_display_init() and vnc_display_open() return bool
      ui/vnc: merge vnc_display_init() and vnc_display_open()
      ui/vnc: add vnc_cleanup()
      ui/vnc: report an error for duplicate display id
      ui/vnc: defer listener registration until the console is known
      ui/vnc: expose vnc_disconnect_start()
      ui/vnc: remove left-over dead code
      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: add doc comment for qemu_console_{un}register_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/vnc: replace VNC_DEBUG with trace-events
      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
      tools/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                          |  222 ++
 meson.build                                      |   17 +
 hw/display/qxl.h                                 |    2 +-
 include/ui/console.h                             |  153 +-
 include/ui/input.h                               |   15 +
 include/ui/qemu-pixman.h                         |    8 +
 include/ui/surface.h                             |    2 -
 tools/qemu-vnc/qemu-vnc.h                        |   46 +
 tools/qemu-vnc/trace.h                           |    4 +
 ui/console-priv.h                                |    8 -
 ui/cp437.h                                       |   13 +
 ui/keymaps.h                                     |    1 +
 ui/vgafont.h                                     | 4618 +---------------------
 ui/vnc-jobs.h                                    |    3 +-
 ui/vnc.h                                         |   22 +-
 ui/vt100.h                                       |   92 +
 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                                |    8 +
 tests/qtest/dbus-vmstate-test.c                  |   13 +-
 tests/qtest/dbus-vnc-test.c                      | 1342 +++++++
 tools/qemu-vnc/audio.c                           |  307 ++
 tools/qemu-vnc/chardev.c                         |  127 +
 tools/qemu-vnc/clipboard.c                       |  378 ++
 tools/qemu-vnc/console.c                         |  168 +
 tools/qemu-vnc/dbus.c                            |  439 ++
 tools/qemu-vnc/display.c                         |  456 +++
 tools/qemu-vnc/input.c                           |  239 ++
 tools/qemu-vnc/qemu-vnc.c                        |  491 +++
 tools/qemu-vnc/stubs.c                           |   62 +
 tools/qemu-vnc/utils.c                           |   59 +
 ui/console-vc-stubs.c                            |    9 +-
 ui/console-vc.c                                  | 1021 +----
 ui/console.c                                     |  491 +--
 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                                        |   22 +-
 ui/spice-display.c                               |   24 +-
 ui/vgafont.c                                     | 4616 +++++++++++++++++++++
 ui/vnc-auth-sasl.c                               |   13 +-
 ui/vnc-enc-tight.c                               |    4 +-
 ui/vnc-enc-zlib.c                                |    4 +-
 ui/vnc-jobs.c                                    |  112 +-
 ui/vnc-system.c                                  |   19 +
 ui/vnc-ws.c                                      |   10 +-
 ui/vnc.c                                         |  291 +-
 ui/vt100.c                                       |  986 +++++
 {system => util}/datadir.c                       |    0
 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                          |   18 +-
 tools/qemu-vnc/meson.build                       |   26 +
 tools/qemu-vnc/qemu-vnc1.xml                     |  174 +
 tools/qemu-vnc/trace-events                      |   20 +
 ui/cocoa.m                                       |   23 +-
 ui/meson.build                                   |  103 +-
 ui/trace-events                                  |   29 +-
 util/meson.build                                 |    1 +
 util/trace-events                                |    3 +
 118 files changed, 11819 insertions(+), 6713 deletions(-)
---
base-commit: becd22fdc2a071783d9e04421526633772b3b98c
change-id: 20260312-qemu-vnc-9662fc572262

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