Windows test VM: a driver script and how to set one up

scripts/windows-vm.sh drives a dockur/windows Windows 11 VM from the Mac over
ssh -J: start/stop, PowerShell, copy files in, screenshots via QEMU's
screendump, clicks and scrolls replayed by a scheduled task in the signed-in
session, QEMU key names, and a tagged, removable headset key for tests
against a real Frame. docs/testing.md explains setting it up (Windows from
Microsoft, loopback-only ports) and the pitfalls found reproducing the
Windows "RDP not working" report. docs/streaming.md records what Remote
Desktop from Windows does against the Frame's xrdp (verified 2026-09-30).

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

scripts/windows-vm.sh

@@ -0,0 +1,128 @@
+#!/usr/bin/env zsh
+# Mac or Linux: drive a Windows 11 test VM for Frame Control's Windows build.
+# The VM is a dockur/windows container on another machine; this reaches it over
+# SSH through that machine. See docs/testing.md#windows-test-vm.
+#
+# Usage: scripts/windows-vm.sh <command> [args]
+#   up | down | status      start it (waits for SSH), shut Windows down cleanly, show state
+#   ps '<PowerShell>'       run PowerShell as the VM's user
+#   put <file> [<dir>]      copy a file in (default: the user's Downloads)
+#   shot <out.png>          save the VM's screen
+#   click <x> <y>           click screen pixel x,y in the signed-in session
+#   scroll <x> <y> <n>      turn the wheel n notches at x,y (negative scrolls down)
+#   keys <key>...           type QEMU key names: a, shift-a, ret, tab, esc, spc ...
+#   frame-key add|remove    let the VM's Frame Control key into the headset (`frame`
+#                           alias) for a test run, then take it out again
+#
+# Set WINVM_HOST to the ssh alias of the machine running the container. Optional:
+# WINVM_CONTAINER (frame-winvm), WINVM_USER (frame), WINVM_PORT (2222: the VM's
+# sshd, published on that machine's loopback), WINVM_KEY (~/.ssh/id_ed25519_winvm).
+set -euo pipefail
+setopt extendedglob
+
+host=${WINVM_HOST:?set WINVM_HOST to the ssh alias of the machine running the VM}
+ctr=${WINVM_CONTAINER:-frame-winvm}
+user=${WINVM_USER:-frame}
+port=${WINVM_PORT:-2222}
+key=${WINVM_KEY:-$HOME/.ssh/id_ed25519_winvm}
+opts=(-o ConnectTimeout=20 -o StrictHostKeyChecking=accept-new
+      -o UserKnownHostsFile=${TMPDIR:-/tmp}/windows-vm-known_hosts -i $key -J $host)
+TAG=windows-vm-test  # comment on the VM's key in the headset's authorized_keys
+
+die() { print -u2 "windows-vm: $*"; exit 1 }
+int() { [[ $1 == (-|)<-> ]] || die "not a whole number: $1" }
+
+# Windows' OpenSSH waits for stdin to close, so it always gets /dev/null. The
+# script travels UTF-16 base64-encoded, so no quoting survives two shells.
+vm_ps() {
+  local b64=$(print -rn -- "\$ProgressPreference = 'SilentlyContinue'"$'\n'"$1" |
+              iconv -f UTF-8 -t UTF-16LE | base64 | tr -d '\n')
+  ssh $opts -p $port $user@127.0.0.1 "powershell -NoProfile -NonInteractive -EncodedCommand $b64" </dev/null
+}
+
+# QEMU's monitor inside the container: one command per line on stdin.
+monitor() { ssh $host "docker exec -i $ctr nc -q 1 -U /run/shm/monitor.sock" >/dev/null }
+
+# Input has to come from the signed-in desktop session, not SSH's session 0, so
+# a scheduled task running as the user replays one click or wheel turn written
+# to input.txt, then deletes the file to say it's done.
+INPUT_PS1='$a = (Get-Content "$PSScriptRoot\input.txt").Trim() -split "\s+"
+Add-Type -Namespace WinVm -Name Input -MemberDefinition @"
+[DllImport("user32.dll")] public static extern bool SetProcessDPIAware();
+[DllImport("user32.dll")] public static extern bool SetCursorPos(int x, int y);
+[DllImport("user32.dll")] public static extern void mouse_event(uint flags, int dx, int dy, int data, System.IntPtr extra);
+"@
+[WinVm.Input]::SetProcessDPIAware() | Out-Null
+[WinVm.Input]::SetCursorPos([int]$a[0], [int]$a[1]) | Out-Null
+Start-Sleep -Milliseconds 150
+if ($a[2] -eq "click") {
+  [WinVm.Input]::mouse_event(0x2, 0, 0, 0, [IntPtr]::Zero); Start-Sleep -Milliseconds 60
+  [WinVm.Input]::mouse_event(0x4, 0, 0, 0, [IntPtr]::Zero)
+} else { [WinVm.Input]::mouse_event(0x800, 0, 0, 120 * [int]$a[3], [IntPtr]::Zero) }
+Remove-Item "$PSScriptRoot\input.txt"'
+
+pointer() {  # x y click|wheel [notches]
+  local b64=$(print -rn -- $INPUT_PS1 | base64 | tr -d '\n')
+  vm_ps '$d = Join-Path $env:LOCALAPPDATA "windows-vm"
+New-Item -ItemType Directory -Force $d | Out-Null
+[IO.File]::WriteAllText("$d\input.ps1", [Text.Encoding]::UTF8.GetString([Convert]::FromBase64String("'$b64'")))
+$act = New-ScheduledTaskAction -Execute powershell.exe -Argument "-NoProfile -WindowStyle Hidden -ExecutionPolicy Bypass -File `"$d\input.ps1`""
+$who = New-ScheduledTaskPrincipal -UserId $env:USERNAME -LogonType Interactive
+Register-ScheduledTask -TaskName WindowsVmInput -Action $act -Principal $who -Force | Out-Null
+Set-Content "$d\input.txt" "'"$*"'"
+Start-ScheduledTask -TaskName WindowsVmInput
+foreach ($i in 1..50) { if (-not (Test-Path "$d\input.txt")) { exit 0 }; Start-Sleep -Milliseconds 200 }
+Remove-Item "$d\input.txt" -ErrorAction SilentlyContinue
+Write-Error "no input after 10 s: is $env:USERNAME signed in on the VM screen?"; exit 1'
+}
+
+(( $# )) || die "usage: see the top of $0"
+cmd=$1; shift
+case $cmd in
+  up)
+    ssh $host "docker start $ctr" >/dev/null
+    for i in {1..60}; do
+      vm_ps 'exit 0' 2>/dev/null && { print "up"; exit 0 }
+      sleep 5
+    done
+    die "Windows didn't answer on SSH within 5 minutes" ;;
+  down)   # the container turns SIGTERM into an ACPI shutdown and waits for Windows
+    ssh $host "docker stop -t 150 $ctr" >/dev/null && print "down" ;;
+  status) ssh $host "docker ps -a --filter 'name=^$ctr\$' --format '{{.Names}}: {{.Status}}'" ;;
+  ps)     (( $# == 1 )) || die "usage: ps '<PowerShell>'"; vm_ps "$1" ;;
+  put)
+    [[ -f ${1:-} ]] || die "usage: put <file> [<dir>]"
+    scp -q $opts -P $port $1 "$user@127.0.0.1:${2:-C:/Users/$user/Downloads}/${1:t}" </dev/null ;;
+  shot)
+    (( $# == 1 )) || die "usage: shot <out.png>"
+    print "screendump /tmp/windows-vm-shot.ppm" | monitor
+    sleep 1
+    ssh $host "docker exec $ctr sh -c 'cat /tmp/windows-vm-shot.ppm && rm /tmp/windows-vm-shot.ppm'" | python3 -c '
+import re, struct, sys, zlib
+d = sys.stdin.buffer.read()
+m = re.match(rb"P6\s+(\d+)\s+(\d+)\s+255\s", d) or sys.exit("windows-vm: no screen dump")
+w, h = int(m[1]), int(m[2]); px = d[m.end():]
+raw = b"".join(b"\0" + px[y * w * 3:(y + 1) * w * 3] for y in range(h))
+chunk = lambda t, b: struct.pack(">I", len(b)) + t + b + struct.pack(">I", zlib.crc32(t + b))
+open(sys.argv[1], "wb").write(b"\x89PNG\r\n\x1a\n" + chunk(b"IHDR", struct.pack(">IIBBBBB", w, h, 8, 2, 0, 0, 0))
+                              + chunk(b"IDAT", zlib.compress(raw)) + chunk(b"IEND", b""))
+' $1
+    print $1 ;;
+  click)  (( $# == 2 )) || die "usage: click <x> <y>"; int $1; int $2; pointer $1 $2 click ;;
+  scroll) (( $# == 3 )) || die "usage: scroll <x> <y> <n>"; int $1; int $2; int $3; pointer $1 $2 wheel $3 ;;
+  keys)
+    (( $# )) || die "usage: keys <key>..."
+    for k; do [[ $k == [a-z0-9_.,/=-]## ]] || die "not a QEMU key name: $k"; done
+    for k; do print "sendkey $k"; done | monitor ;;
+  frame-key)
+    pub=$(vm_ps 'Get-Content (Join-Path $env:USERPROFILE ".ssh\id_ed25519_frame.pub")' | tr -d '\r')
+    pub=${${(z)pub}[1,2]}
+    [[ $pub == ssh-ed25519\ * ]] || die "the VM has no Frame Control key yet: run Set Up Connection in the app first"
+    case ${1:-} in
+      add)    ssh frame "grep -qxF '$pub $TAG' ~/.ssh/authorized_keys || echo '$pub $TAG' >> ~/.ssh/authorized_keys" </dev/null ;;
+      remove) ssh frame "f=~/.ssh/authorized_keys; grep -v ' $TAG\$' \$f > \$f.tmp; chmod 600 \$f.tmp; mv \$f.tmp \$f" </dev/null ;;
+      *)      die "usage: frame-key add|remove" ;;
+    esac
+    print "frame-key $1: done" ;;
+  *) die "unknown command: $cmd (see the top of $0)" ;;
+esac