android-emulator: api36-v6 — cap RLIMIT_NOFILE; x11vnc -nolookup

Viktor's noVNC sat at 'Connecting…' forever: the WebSocket traversed
Cloudflare/Authentik/websockify fine, but x11vnc never sent the RFB
banner — strace showed it sweeping the container's fd table with one
fcntl per fd, and containerd grants RLIMIT_NOFILE=2147483584 here, so
each connection effectively never completed. The entrypoint now sets
ulimit -n 65536 for everything it launches (verified live: banner
answers instantly under the capped limit); x11vnc also gets -nolookup
so client reverse-DNS can never stall handshakes.

stacks/android-emulator/docker/Dockerfile

@@ -4,8 +4,8 @@
 # cmdline-tools and the native libraries the emulator needs at runtime.
 #
 # Rebuild + push (rare — only when tool/library versions bump):
-#   docker build -t forgejo.viktorbarzin.me/viktor/android-emulator:api36-v5 .
-#   docker push forgejo.viktorbarzin.me/viktor/android-emulator:api36-v5
+#   docker build -t forgejo.viktorbarzin.me/viktor/android-emulator:api36-v6 .
+#   docker push forgejo.viktorbarzin.me/viktor/android-emulator:api36-v6
 FROM eclipse-temurin:17-jdk-jammy
 
 ENV DEBIAN_FRONTEND=noninteractive

stacks/android-emulator/docker/entrypoint.sh

@@ -4,6 +4,11 @@
 # emulator windowed into it, and expose its adbd on :5555 for the LAN.
 set -euo pipefail
 
+# Containerd grants an effectively unbounded RLIMIT_NOFILE (2^31); x11vnc's
+# connection handling sweeps the whole fd table with fcntl per fd, so every
+# VNC connect hung for ages. Cap it for everything we launch.
+ulimit -n 65536
+
 API_LEVEL="${API_LEVEL:-36}"
 SYSTEM_IMAGE="system-images;android-${API_LEVEL};google_apis;x86_64"
 # Pinned emulator build (36.1.9). The sdkmanager-latest emulator (36.6.11)
@@ -79,7 +84,7 @@ export DISPLAY=:0
 Xvfb :0 -screen 0 "$SCREEN_GEOMETRY" -nolisten tcp &
 sleep 1
 openbox &
-x11vnc -display :0 -nopw -forever -shared -quiet -bg
+x11vnc -display :0 -nopw -forever -shared -quiet -nolookup -bg
 websockify --web /usr/share/novnc 6080 localhost:5900 &
 
 # --- emulator -----------------------------------------------------------------

stacks/android-emulator/variables.tf

@@ -5,6 +5,6 @@ variable "tls_secret_name" {
 
 variable "image_tag" {
   type        = string
-  default     = "api36-v5"
+  default     = "api36-v6"
   description = "android-emulator image tag at forgejo.viktorbarzin.me/viktor/android-emulator. Built + pushed manually from stacks/android-emulator/docker/ (see README.md) — bump this when the image is rebuilt."
 }