Files
saphid--frame-control/ui/frame_macview.py
T
saphidandClaude Opus 5.5 bda9d77d2d Mac in the headset: USB route keeps a configured host-key alias and falls back to the network
Review round 12: a failed USB-C tunnel now retries the normal path; an
existing HostKeyAlias wins; --host with --usb is rejected; the Steam
desktop-streaming claim is now 'untested' (Valve documents the desktop
showing when a game loses focus); the Show/cleanup overlap test blocks
for real (it fails without the lock). Verified live: with the cable out,
the route is the normal path.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-09-28 21:39:40 +10:00

457 lines
20 KiB
Python

"""Mac in the headset: stream Mac windows or displays into the Steam Frame as
panels you can place anywhere, with the laser, wheel and keys driving the Mac.
Runs on the Mac, inside Frame Control's server. The pieces:
- mac/bin/frame-mac-view (Swift, built from mac/frame-mac-view): captures with
ScreenCaptureKit, encodes with VideoToolbox, serves ui/mac-view.html and one
WebSocket per stream on 127.0.0.1, and plays input back with CGEvent.
- An `ssh -R` tunnel, so the Frame reaches the agent on its own 127.0.0.1.
Every request carries a random token, so other programs on the Frame
(Android apps included) can't watch or drive the Mac.
- A Chromium app window on the Frame per stream, on gamescope's X display
with its own STEAM_GAME id, which makes it its own SteamVR panel (see
docs/panels.md). Chromium XR (~/chromium-xr) is preferred because it's
built with H.264; Flathub Chromium is the fallback.
Stdlib only. MacView gets a plain ssh argv for the tunnel (its own
connection) and the server's `run(remote, stdin=, timeout=)` for commands.
"""
import json
import os
import re
import secrets
import shutil
import socket
import subprocess
import sys
import threading
import time
import urllib.error
import urllib.request
import zlib
from pathlib import Path
from urllib.parse import quote, urlencode # %20, not +: the agent's URLComponents keeps +
HERE = Path(__file__).resolve().parent
ROOT = HERE.parent
PAGE = HERE / "mac-view.html"
SOURCES = ROOT / "mac" / "frame-mac-view"
AGENT = Path(os.environ.get("FRAME_MAC_VIEW") or ROOT / "mac" / "bin" / "frame-mac-view")
REMOTE_PORTS = range(47900, 47920)
SUPPORTED = sys.platform == "darwin"
# Stream settings by name: long side in pixels, frames per second, H.264 bits
# per pixel per frame, codec. JPEG is for a Frame browser without H.264.
QUALITY = {
"sharp": {"max": 2560, "fps": 60, "bpp": 0.14, "codec": "h264"},
"balanced": {"max": 1920, "fps": 60, "bpp": 0.1, "codec": "h264"},
"light": {"max": 1280, "fps": 30, "bpp": 0.08, "codec": "h264"},
"compatible": {"max": 1280, "fps": 20, "bpp": 0.1, "codec": "jpeg"},
}
# Extra Chromium flags for viewers (see docs/mac-in-headset.md, "Measuring").
BROWSER_FLAGS = []
# Viewer windows are fitted inside a panel's size. gamescope made a 1280x720
# request 1920x1080 anyway (verified 2026-09-28, build 20260925.6191901).
PANEL_BOX = (1920, 1080)
# Opens one viewer on gamescope's X display and gives its window its own panel
# id. Args: appid url width height tag [browser flags...]. The page puts "[tag]" in its title at
# once, which is how its X window is found (Chromium may hand the URL to an
# instance that's already running, so there's no process to follow).
LAUNCH = r"""set -u
appid=$1 url=$2 w=$3 h=$4 tag=$5
shift 5
export DISPLAY=:0 LC_ALL=C.UTF-8
unset WAYLAND_DISPLAY
if ! xprop -root GAMESCOPE_FOCUSABLE_WINDOWS >/dev/null 2>&1; then
echo "The headset isn't showing anything (gamescope's display :0 isn't up). Wake it and try again." >&2
exit 2
fi
common=(--ozone-platform=x11 --force-device-scale-factor=1 --no-first-run --no-default-browser-check
--password-store=basic --disable-session-crashed-bubble --noerrdialogs --disable-infobars
--disable-features=Translate,MediaRouter --autoplay-policy=no-user-gesture-required
"--window-size=$w,$h" "$@" "--app=$url")
if [ -x "$HOME/chromium-xr/chrome" ]; then
cmd=("$HOME/chromium-xr/chrome" "--user-data-dir=$HOME/.local/share/frame-control/mac-view" "${common[@]}")
elif flatpak info org.chromium.Chromium >/dev/null 2>&1; then
cmd=(flatpak run org.chromium.Chromium
"--user-data-dir=$HOME/.var/app/org.chromium.Chromium/data/frame-mac-view" "${common[@]}")
else
echo "NO_BROWSER"
exit 3
fi
log=/tmp/frame-mac-view.log
setsid nohup "${cmd[@]}" >>"$log" 2>&1 </dev/null &
for _ in $(seq 1 60); do
sleep 0.5
# xprop, not xwininfo: in a C locale xwininfo can't print a non-ASCII title
# at all, while xprop escapes those bytes and leaves the ASCII tag readable.
for win in $(xwininfo -root -children 2>/dev/null | awk '/^ +0x/ {print $1}'); do
xprop -id "$win" _NET_WM_NAME WM_NAME 2>/dev/null | grep -qF "[$tag]" || continue
if xprop -id "$win" -f STEAM_GAME 32c -set STEAM_GAME "$appid" 2>/dev/null; then
echo "panel valve.steam.desktopgame.$appid window $win"
exit 0
fi
done
done
echo "The viewer started, but its window didn't appear within 30 s. Chromium's log:" >&2
tail -n 15 "$log" >&2
exit 1
"""
class MacViewError(Exception):
pass
def panel_id(src):
"""A stable panel id per source, in the range panel-on-frame.sh uses."""
return 2_001_000_000 + zlib.crc32(f"mac:{src}".encode()) % 1_000_000
def fit(w, h, box=PANEL_BOX):
s = min(box[0] / max(w, 1), box[1] / max(h, 1))
return max(320, round(w * s)), max(200, round(h * s))
class MacView:
def __init__(self, tunnel_ssh, run, frame, track=None):
self.tunnel_ssh = list(tunnel_ssh)
self.run = run
self.frame = frame
self.track = track or (lambda proc: None) # the server ends these on exit
self.lock = threading.Lock()
self.token = secrets.token_urlsafe(24)
self.agent = None
self.port = None
self.tunnel = None
self.remote_port = None
self.supervisor = None
self.closing = False
self.shows = 0 # counts Show presses, so a late cleanup can't close a new viewer
self.launching = 0 # Shows in progress (one may be replacing its own stream)
# Held by a Show while it counts itself in, and by the cleanup for its
# check and its pkill together, so a Show can't start in between.
self.viewer_lock = threading.Lock()
# Use the Frame's USB-C network when it's plugged into this Mac (see
# _usb_route); FRAME_MACVIEW_USB=0 turns that off.
self.prefer_usb = os.environ.get("FRAME_MACVIEW_USB") != "0"
self.route = "network"
self.shown = set() # sources with a viewer out there, connected or retrying
self.browser_flags = list(BROWSER_FLAGS)
# ---- the agent on this Mac ----
def unavailable(self):
"""Why this can't work here, or None."""
if not SUPPORTED:
return "Streaming your computer into the headset needs macOS."
if not AGENT.exists() and not (SOURCES.exists() and shutil.which("xcrun")):
return "The Mac streaming helper is missing from this copy of Frame Control."
return None
def build(self):
if AGENT.exists() and not self._stale():
return
if not (SOURCES / "build.sh").exists():
if AGENT.exists():
return
raise MacViewError("The Mac streaming helper is missing.")
r = subprocess.run(["/bin/sh", str(SOURCES / "build.sh"), str(AGENT)], capture_output=True, text=True,
stdin=subprocess.DEVNULL, timeout=600)
if r.returncode != 0:
raise MacViewError("Couldn't build the Mac streaming helper: " + (r.stderr or r.stdout).strip()[-400:])
def _stale(self):
try:
built = AGENT.stat().st_mtime
return any(p.stat().st_mtime > built for p in (SOURCES / "Sources").glob("*.swift"))
except OSError:
return False
def ensure_agent(self):
with self.lock:
if self.agent and self.agent.poll() is None:
return
reason = self.unavailable()
if reason:
raise MacViewError(reason)
self.build()
env = {**os.environ, "FRAME_MAC_VIEW_TOKEN": self.token}
# The same port as before when restarting, so a running tunnel still
# fits; otherwise (or if it's gone) whatever the system gives.
for port in dict.fromkeys([self.port or 0, 0]):
self.agent = subprocess.Popen([str(AGENT), "serve", "--port", str(port), "--page", str(PAGE),
"--exit-on-eof"], env=env, stdin=subprocess.PIPE,
stdout=subprocess.PIPE, stderr=subprocess.STDOUT, text=True)
line = self.agent.stdout.readline()
m = re.search(r"listening on 127\.0\.0\.1:(\d+)", line)
if m:
break
self.agent.kill()
else:
raise MacViewError(f"The Mac streaming helper didn't start: {line.strip() or 'no output'}")
if self.port != int(m.group(1)):
self._drop_tunnel()
self.port = int(m.group(1))
self.track(self.agent)
threading.Thread(target=self.agent.stdout.read, daemon=True).start() # drain
def call(self, path, method="GET", **query):
"""A request to the agent; starts it if needed."""
self.ensure_agent()
url = f"http://127.0.0.1:{self.port}{path}?{urlencode({**query, 'k': self.token}, quote_via=quote)}"
req = urllib.request.Request(url, method=method, data=b"" if method == "POST" else None)
try:
with urllib.request.urlopen(req, timeout=10) as r:
return json.load(r)
except (urllib.error.URLError, OSError, ValueError) as e:
raise MacViewError(f"The Mac streaming helper didn't answer: {e}")
# ---- the tunnel from the Frame ----
def _drop_tunnel(self):
if self.tunnel and self.tunnel.poll() is None:
self.tunnel.terminate()
self.tunnel = None
def tunnel_up(self):
return self.tunnel is not None and self.tunnel.poll() is None
def ensure_tunnel(self, allow_new_port=False):
"""Open the tunnel, on the port viewers already use if there is one.
A new port only when nobody is watching, since viewers can't move."""
with self.lock:
if self.tunnel_up():
return
last = ""
ports = [self.remote_port] if self.remote_port else list(REMOTE_PORTS)
if self.remote_port and allow_new_port:
ports += [p for p in REMOTE_PORTS if p != self.remote_port]
usb = self._usb_route()
# USB-C first when it's there; if that fails (unplugged just now,
# something else at that address), the normal path.
for via in ([usb, []] if usb else [[]]):
self.route = "usb" if via else "network"
if self._open_tunnel(via, ports):
return
last = self._last_tunnel_error
raise MacViewError(f"Couldn't open a tunnel from {self.frame} to this Mac: {last or 'no answer through it'}")
def _open_tunnel(self, via, ports):
"""Tries the ports on one route; True once the tunnel answers. With self.lock held."""
last = ""
for port in ports:
proc = subprocess.Popen([*self.tunnel_ssh, *via, "-o", "ExitOnForwardFailure=yes",
"-o", "ServerAliveInterval=5", "-o", "ServerAliveCountMax=3", "-N",
"-R", f"127.0.0.1:{port}:127.0.0.1:{self.port}", self.frame],
stdin=subprocess.DEVNULL, stdout=subprocess.DEVNULL,
stderr=subprocess.PIPE, text=True)
# A taken port makes ssh exit once it's connected; a working
# tunnel answers the agent's status from the Frame's side.
ok = False
for _ in range(15):
time.sleep(0.4)
if proc.poll() is not None:
break
if self._probe(port):
ok = True
break
if ok:
self.tunnel, self.remote_port = proc, port
self.track(proc)
self._supervise()
return True
if proc.poll() is None:
proc.terminate()
proc.wait()
last = (proc.stderr.read() or "").strip()
if "forward" not in last.lower():
break # not a port clash: the Frame is unreachable this way
self._last_tunnel_error = last
return False
def _usb_route(self):
"""ssh options to reach the Frame over its USB-C network, or [].
Plugged into a Mac, the Frame is a USB network device (macOS lists it
as "Steam Frame"): the Frame's usb0 answers at about 1 ms, with none
of Wi-Fi's stalls. Measured 2026-09-28: content latency 7 ms instead
of 10, click to screen 17 ms instead of 27 (docs/mac-in-headset.md).
The host key is the same, so it's checked against the usual name."""
if not self.prefer_usb:
return []
try:
out = self.run("ip -4 -o addr show usb0 2>/dev/null", timeout=8)
except Exception:
return []
m = re.search(r"inet (\d+\.\d+\.\d+\.\d+)/", out or "")
if not m:
return []
ip = m.group(1)
try:
socket.create_connection((ip, 22), timeout=1).close()
except OSError:
return [] # not plugged into this Mac
alias = self.frame
try:
cfg = subprocess.run(["ssh", "-G", self.frame], capture_output=True, text=True, timeout=5).stdout
opts = dict(line.split(None, 1) for line in cfg.splitlines() if " " in line)
alias = opts.get("hostkeyalias") or opts.get("hostname") or alias # a configured alias wins
except (OSError, subprocess.SubprocessError):
pass
return ["-o", f"HostName={ip}", "-o", f"HostKeyAlias={alias}"]
def _supervise(self):
"""Reopen the tunnel on the same port after the headset sleeps or the
network drops, so viewers that are retrying find the Mac again."""
if self.supervisor and self.supervisor.is_alive():
return
def loop():
while not self.closing:
time.sleep(5)
if self.closing or self.tunnel_up() or not (self.agent and self.agent.poll() is None):
continue
try:
self.ensure_tunnel()
except MacViewError:
pass # still unreachable; try again shortly
self.supervisor = threading.Thread(target=loop, daemon=True)
self.supervisor.start()
def _probe(self, port):
"""Whether the Frame reaches the agent through the tunnel on `port`."""
# /ping needs no key, so none appears on the Frame's command lines.
cmd = f"curl -s -m 2 'http://127.0.0.1:{port}/ping'"
try:
return self.run(cmd, timeout=8).strip() == "frame-mac-view"
except Exception: # noqa: BLE001 - the server's Failure, timeouts: all mean "not yet"
return False
# ---- viewers on the Frame ----
def show(self, src, quality="balanced", width=None, height=None):
with self.viewer_lock:
self.launching += 1
try:
return self._show(src, quality, width, height)
finally:
with self.viewer_lock:
self.launching -= 1
def _show(self, src, quality, width, height):
if src != "test" and not src.startswith(("window:", "display:", "separate:")):
raise MacViewError("Pick a window or display to show.")
self.shows += 1
q = QUALITY.get(quality) or QUALITY["balanced"]
state = self.call("/status")
if src != "test" and not state.get("screen"):
raise MacViewError("Frame Control needs Screen Recording permission first (Allow… under Mac in the headset).")
if src.startswith("separate:") and not state.get("accessibility"):
raise MacViewError("A window on its own display needs the Accessibility permission too, to move it "
"(Allow… under Mac in the headset).")
self.shown -= set(state.get("finished", [])) # their Mac windows closed
if src in self.shown or any(st.get("src") == src for st in state.get("streams", [])):
# Showing it again replaces the old viewer, connected or not: this
# revokes its keys so it can't come back alongside the new one.
self.stop(src)
# Viewers that lost the tunnel keep retrying its old port, even though
# the agent no longer counts them, so only move when none are out there.
others = self.shown - {src}
self.ensure_tunnel(allow_new_port=not others)
appid = panel_id(src)
# Unique per launch, so a new window is never confused with an old one.
tag = "fc" + secrets.token_hex(4)
# A single-use ticket for this source, not Frame Control's key: the URL
# is visible in the Frame's process list.
ticket = self.call("/ticket", method="POST", src=src)["ticket"]
params = {"src": src, "t": ticket, "tag": tag, "codec": q["codec"], "max": q["max"], "fps": q["fps"],
"bpp": q["bpp"]}
url = f"http://127.0.0.1:{self.remote_port}/view?{urlencode(params)}"
w, h = fit(width or 1280, height or 720)
args = " ".join(_quote(str(a)) for a in (appid, url, w, h, tag, *self.browser_flags))
try:
out = self.run("bash -s -- " + args, stdin=LAUNCH, timeout=60)
except Exception as e: # noqa: BLE001 - the server's Failure carries the Frame's words
if "NO_BROWSER" in (getattr(e, "stdout", "") or ""):
raise MacViewError("The Frame needs a browser for this: install Chromium (Tools → Linux apps, "
"org.chromium.Chromium) or Chromium XR.")
raise MacViewError(str(e))
self.shown.add(src)
return {"panel": f"valve.steam.desktopgame.{appid}", "src": src, "detail": out.strip()}
def stop(self, src=None):
if src:
self.shown.discard(src)
else:
self.shown.clear()
if not (self.agent and self.agent.poll() is None):
return {"closed": 0}
out = self.call("/close", method="POST", **({"src": src} if src else {}))
if not self.shown:
threading.Thread(target=self._end_viewer_browser, args=(self.shows,), daemon=True).start()
return out
def _end_viewer_browser(self, shows):
"""Chromium on the Frame outlives its last viewer window (verified
2026-09-28), so once nothing is shown, end it. It runs with a profile
of its own, so nothing else is touched."""
time.sleep(2) # the viewers close their windows first
with self.viewer_lock:
if self.shown or self.shows != shows or self.launching:
return
try:
self.run("pkill -f '[f]rame-control/mac-view|[d]ata/frame-mac-view' || true", timeout=10)
except Exception:
pass
def state(self):
reason = self.unavailable()
if reason:
return {"available": False, "reason": reason}
status = self.call("/status")
windows = self.call("/windows").get("windows", []) if status.get("screen") else []
displays = self.call("/displays").get("displays", [])
return {"available": True, "screen": status.get("screen", False),
"accessibility": status.get("accessibility", False), "streams": status.get("streams", []),
"windows": windows, "displays": displays, "tunnel": self.tunnel_up(),
"route": self.route}
def restart_agent(self):
"""Only if it's missing a permission: a running stream would stop."""
with self.lock:
if not (self.agent and self.agent.poll() is None):
return
status = self.call("/status")
if status.get("screen") and status.get("accessibility"):
return
with self.lock:
self.agent.terminate()
self.agent.wait(5)
def request_permissions(self):
return self.call("/permissions", method="POST")
def shutdown(self):
self.closing = True
try:
self.stop()
except MacViewError:
pass
for proc in (self.tunnel, self.agent):
if proc and proc.poll() is None:
proc.terminate()
# The helper puts separated windows back before it exits (about 1 s).
if self.agent:
try:
self.agent.wait(3)
except subprocess.TimeoutExpired:
self.agent.kill()
def _quote(s):
return "'" + s.replace("'", "'\\''") + "'"