docs: Readme (#1358)

.github/dependabot.yml

@@ -1,10 +1,21 @@
 version: 2
+
 updates:
   - package-ecosystem: docker
     directory: /
     schedule:
       interval: weekly
+    cooldown:
+      default-days: 7
+
   - package-ecosystem: github-actions
     directory: /
     schedule:
       interval: weekly
+    cooldown:
+      default-days: 7
+    ignore:
+      - dependency-name: "*"
+        update-types:
+          - version-update:semver-minor
+          - version-update:semver-patch

.github/workflows/check.yml

@@ -1,5 +1,7 @@
 on: [workflow_call]
+
 name: "Check"
+
 permissions: {}
 
 jobs:
@@ -7,24 +9,29 @@ jobs:
     name: shellcheck
     runs-on: ubuntu-latest
     steps:
-    - 
-      name: Checkout
-      uses: actions/checkout@v7
-    - parallel:
       -
-        name: Run ShellCheck
-        uses: ludeeus/action-shellcheck@master
-        env:
-          SHELLCHECK_OPTS: -x --source-path=src -e SC2001 -e SC2034 -e SC2064 -e SC2317 -e SC2153 -e SC2028
-      - 
-        name: Lint Dockerfile
-        uses: hadolint/hadolint-action@v3.3.0
-        with:
-          dockerfile: Dockerfile
-          ignore: DL3008,DL3003,DL3006,DL3013
-          failure-threshold: warning
-      -
-        name: Validate JSON and YML files
-        uses: GrantBirki/json-yaml-validate@v5.0.0
-        with:
-          yaml_exclude_regex: ".*\\kubernetes\\.yml$"
+        name: Checkout
+        uses: actions/checkout@v7
+      - parallel:
+          -
+            name: Run ShellCheck
+            uses: ludeeus/action-shellcheck@master
+            env:
+              SHELLCHECK_OPTS: >-
+                -x
+                --source-path=src
+                -e SC1091
+                -e SC2001
+                -e SC2034
+                -e SC2317
+                -e SC2153
+          -
+            name: Lint Dockerfile
+            uses: hadolint/hadolint-action@v3.4.0
+            with:
+              dockerfile: Dockerfile
+              ignore: DL3008
+              failure-threshold: warning
+          -
+            name: Validate JSON and YML files
+            uses: GrantBirki/json-yaml-validate@v5

.github/workflows/review.yml

@@ -11,61 +11,4 @@ permissions:
 jobs:
   review:
     name: review
-    runs-on: ubuntu-latest
-    steps:
-    -
-      name: Checkout
-      uses: actions/checkout@v7
-    - parallel:
-      -
-        name: Spelling
-        uses: reviewdog/action-misspell@v1
-        with:
-          locale: "US"
-          level: warning
-          pattern: |
-            *.md
-            *.sh
-          reporter: github-pr-review
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-      -
-        name: Hadolint
-        uses: reviewdog/action-hadolint@v1
-        with:
-          level: warning
-          fail_level: error
-          reporter: github-pr-review
-          hadolint_ignore: DL3008 DL3003 DL3006 DL3013
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-      -
-        name: YamlLint
-        uses: reviewdog/action-yamllint@v1
-        with:
-          level: warning
-          reporter: github-pr-review
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-      -
-        name: ActionLint
-        uses: reviewdog/action-actionlint@v1
-        with:
-          level: warning
-          reporter: github-pr-review
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-      -
-        name: Shellformat
-        uses: reviewdog/action-shfmt@v1
-        if: false
-        with:
-          level: warning
-          fail_on_error: "true"
-          shfmt_flags: "-i 2 -ci -bn"
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-      -
-        name: Shellcheck
-        uses: reviewdog/action-shellcheck@v1
-        with:
-          level: warning
-          fail_level: error
-          reporter: github-pr-review
-          shellcheck_flags: -x -e SC1091 -e SC2001 -e SC2034 -e SC2064 -e SC2317 -e SC2153 -e SC2028
-          github_token: ${{ secrets.GITHUB_TOKEN }}
+    uses: action-pack/.github/.github/workflows/review.yml@master

.gitignore

@@ -1 +1,268 @@
-build.sh
+##############################
+# Operating System Files
+##############################
+
+.DS_Store
+.AppleDouble
+.LSOverride
+Thumbs.db
+ehthumbs.db
+Desktop.ini
+Icon?
+$RECYCLE.BIN/
+.Spotlight-V100/
+.Trashes/
+.fseventsd
+
+##############################
+# IDEs
+##############################
+
+.vscode/
+.idea/
+*.iml
+*.ipr
+*.iws
+
+##############################
+# VS Code
+##############################
+
+.history/
+*.code-workspace
+
+##############################
+# Vim
+##############################
+
+*.swp
+*.swo
+Session.vim
+
+##############################
+# Sublime
+##############################
+
+*.sublime-workspace
+*.sublime-project
+
+##############################
+# Temporary Files
+##############################
+
+*.tmp
+*.temp
+*.bak
+*.old
+*.orig
+*.rej
+*.save
+
+##############################
+# Logs
+##############################
+
+*.log
+logs/
+log/
+*.out
+*.err
+*.trace
+
+##############################
+# Runtime
+##############################
+
+*.pid
+*.seed
+*.pid.lock
+
+##############################
+# Secrets
+##############################
+
+.env
+.env.*
+!.env.example
+*.pem
+*.key
+*.crt
+*.cer
+*.p12
+*.pfx
+*.kdbx
+*.secret
+*.token
+
+##############################
+# SSH
+##############################
+
+.ssh/
+
+##############################
+# Docker
+##############################
+
+docker-compose.override.yml
+docker-compose.local.yml
+
+##############################
+# VM Storage
+##############################
+
+storage/
+windows/
+downloads/
+
+##############################
+# Disk Images
+##############################
+
+*.qcow2
+*.qcow
+*.vhd
+*.vhdx
+*.vdi
+*.raw
+*.img
+*.iso
+*.bin
+
+##############################
+# QEMU
+##############################
+
+*.nvram
+*.fd
+*.efi
+*.sock
+*.monitor
+*.serial
+
+##############################
+# Samba
+##############################
+
+shared/
+share/
+
+##############################
+# Backups
+##############################
+
+backup/
+backups/
+*.backup
+
+##############################
+# Cache
+##############################
+
+.cache/
+.cache-loader/
+.tmp/
+temp/
+tmp/
+
+##############################
+# Python
+##############################
+
+__pycache__/
+*.py[cod]
+.pytest_cache/
+.mypy_cache/
+.venv/
+venv/
+
+##############################
+# Node
+##############################
+
+node_modules/
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+pnpm-debug.log*
+
+##############################
+# Build
+##############################
+
+dist/
+build/
+out/
+release/
+
+##############################
+# Coverage
+##############################
+
+coverage/
+.coverage
+coverage.xml
+
+##############################
+# Archives
+##############################
+
+*.zip
+*.tar
+*.tar.gz
+*.tgz
+*.7z
+*.rar
+
+##############################
+# Generated Config
+##############################
+
+config.local.*
+settings.local.*
+local.env
+
+##############################
+# Test Files
+##############################
+
+test-output/
+playwright-report/
+
+##############################
+# macOS
+##############################
+
+.AppleDB
+.AppleDesktop
+Network Trash Folder
+Temporary Items
+
+##############################
+# Linux
+##############################
+
+*~
+.nfs*
+
+##############################
+# Windows
+##############################
+
+*.stackdump
+
+##############################
+# Misc
+##############################
+
+*.cache
+*.lock
+*.lock.json
+*.bak.*
+
+##############################
+# Keep Examples
+##############################
+
+!.gitkeep
+!.env.example

Dockerfile

@@ -1,12 +1,15 @@
 # syntax=docker/dockerfile:1
 
-FROM qemux/qemu-host:2.05 AS builder
+FROM qemux/qemu-host:2.06 AS builder
 FROM debian:trixie-slim
 
 ARG TARGETARCH
 ARG TARGETPLATFORM
+
 ARG VERSION_ARG="0.0"
-ARG VERSION_PASST="2026_06_11"
+ARG VERSION_WSD="0.4.2"
+ARG VERSION_CSTRUCT="4.7"
+ARG VERSION_PASST="2026_07_28"
 
 ARG DEBCONF_NOWARNINGS="yes"
 ARG DEBIAN_FRONTEND="noninteractive"
@@ -27,10 +30,6 @@ RUN <<EOF
     procps \
     ipcalc \
     ethtool \
-    python3 \
-    python3-pip \
-    python3-msgpack \
-    python3-pysodium \
     xz-utils \
     iptables \
     iproute2 \
@@ -39,30 +38,30 @@ RUN <<EOF
     apt-utils \
     net-tools \
     e2fsprogs \
+    diffutils \
     qemu-utils \
-    websocketd \
     iputils-ping \
     inotify-tools \
     ca-certificates \
     netcat-openbsd \
-    qemu-system-x86
+    qemu-system-x86 \
+    python3 \
+    python3-pip \
+    python3-msgpack \
+    python3-pysodium
 
   # Install Passt package
   wget "https://github.com/qemus/passt/releases/download/v${VERSION_PASST}/passt_${VERSION_PASST}_${TARGETARCH}.deb" -O /tmp/passt.deb -q --timeout=10
   dpkg -i /tmp/passt.deb
 
+  # Install Websocketd package
+  wget "https://github.com/qemus/websocketd/releases/download/v${VERSION_WSD}/websocketd-${VERSION_WSD}_${TARGETARCH}.deb" -O /tmp/wsd.deb -q --timeout=10
+  dpkg -i /tmp/wsd.deb
+
   apt-get clean
 
   # Install Python dependencies
-  pip3 install --no-cache-dir --break-system-packages --root-user-action=ignore dissect.cstruct
-
-  # Configure QEMU
-  mkdir -p /etc/qemu
-  echo "allow br0" > /etc/qemu/bridge.conf
-
-  # Configure nginx
-  unlink /etc/nginx/sites-enabled/default
-  sed -i 's/^worker_processes.*/worker_processes 1;/' /etc/nginx/nginx.conf
+  pip3 install --no-cache-dir --break-system-packages --root-user-action=ignore "dissect.cstruct==$VERSION_CSTRUCT"
 
   # Set version file
   echo "$VERSION_ARG" > /etc/version

docs/environment.md

@@ -8,7 +8,8 @@ An empty default means the variable is unset and its value is determined automat
 
 | Variable | Default | Description |
 |---|---|---|
-| `URL` |  | URL or local path to the DSM `.pat` installation file. Downloads the default Virtual DSM image automatically when unset. |
+| `URL` |  | URL or local path to a custom `.pat` installation file. |
+| `COUNTRY` |  | Country code used to select the Synology download mirror. |
 | `HOST_MAC` |  | MAC address reported to DSM. |
 | `HOST_MODEL` |  | Synology host model reported to DSM. |
 | `HOST_SERIAL` |  | Synology host serial number reported to DSM. |
@@ -38,6 +39,7 @@ An empty default means the variable is unset and its value is determined automat
 | `DISK_DISCARD` | `unmap` | Discard/TRIM mode for the primary disk. |
 | `DISK_ROTATION` | `1` | Rotation rate reported to the guest. Use `1` to identify the disk as an SSD. |
 | `DISK_FLAGS` |  | Additional options used when creating `qcow2` disks. |
+| `DISK_OPTIONS` |  | Additional options appended to QEMU disk devices. |
 | `ALLOCATE` | `N` | Preallocates space for the data disks. |
 | `STORAGE` | `/storage` | Storage directory used for disks, settings, and downloads. |
 
@@ -45,15 +47,15 @@ An empty default means the variable is unset and its value is determined automat
 
 | Variable | Default | Description |
 |---|---|---|
-| `NETWORK` |  | Network mode, such as `nat`, `passt`, `slirp`, or `N` to disable networking. |
-| `DHCP` | `N` | Enables macvtap networking so  DSM receives an address from the external LAN through DHCP. |
-| `HOST` | `VirtualDSM` | Hostname assigned to DSM. |
+| `NETWORK` |  | Network mode, such as `nat`, `user`, or `N` to disable networking. |
+| `DHCP` | `N` | Enables macvtap networking so DSM receives a DHCP address. |
+| `HOST` |  | Hostname assigned to the machine on the network. |
 | `IP` |  | Overrides the automatically selected guest IPv4 address. |
 | `MAC` |  | Guest network adapter MAC address. |
 | `ADAPTER` | `virtio-net-pci` | QEMU network adapter model. |
 | `DEV` | `eth0` | Container network interface used as the uplink. |
 | `MTU` |  | MTU assigned to the guest network interface. |
-| `MASK` | `255.255.255.0` | IPv4 netmask. |
+| `MASK` | `255.255.255.0` | IPv4 netmask for guest network. |
 | `TAP` | `dsm` | TAP or macvtap interface name. |
 | `BRIDGE` | `docker` | Bridge name used for NAT networking. |
 | `HOST_PORTS` |  | Ports excluded from guest forwarding. |
@@ -69,10 +71,18 @@ An empty default means the variable is unset and its value is determined automat
 | Variable | Default | Description |
 |---|---|---|
 | `DISPLAY` | `none` | Display backend, such as `vnc`, `disabled`, or `none`. |
+| `LOSSY` | `N` | Enables lossy VNC compression to reduce bandwidth usage. |
 | `VGA` | `none` | QEMU video adapter model. |
 | `GPU` | `N` | Enables Intel iGPU acceleration. |
 | `RENDERNODE` | `/dev/dri/renderD128` | Render node used for GPU acceleration. |
 
+## ⚙️ System
+
+| Variable | Default | Description |
+|---|---|---|
+| `MACHINE` | `q35` | QEMU machine type. |
+| `ARGUMENTS` |  | Additional raw arguments appended to the QEMU command line. |
+
 ## 🔌 Shutdown
 
 | Variable | Default | Description |
@@ -87,7 +97,4 @@ An empty default means the variable is unset and its value is determined automat
 |---|---|---|
 | `DEBUG` | `N` | Enables verbose debug output. |
 | `TRACE` | `N` | Enables shell command tracing. |
-| `COM_PORT` | `2210` | Internal communication port used by the DSM host helper. |
-| `CHR_PORT` | `12345` | Internal character device port used by the DSM host helper. |
 | `HOST_DEBUG` | `N` | Enables debug output for the DSM host helper. |
-| `ARGUMENTS` |  | Additional raw arguments appended to the QEMU command line. |

kubernetes.yml

@@ -18,6 +18,8 @@ metadata:
     name: dsm
 spec:
   replicas: 1
+  strategy:
+    type: Recreate
   selector:
     matchLabels:
       app: dsm

readme.md

@@ -68,8 +68,8 @@ kubectl apply -f https://raw.githubusercontent.com/vdsm/virtual-dsm/refs/heads/m
 
 - Docker or Podman on a Linux host with KVM support.
 - Docker Desktop or Podman (Desktop) on Windows 11 with nested virtualization enabled.
-- At least 2 GB of available RAM.
-- At least 32 GB of free disk space.
+- At least 1 GB of available RAM.
+- At least 16 GB of free disk space.
 
 > [!NOTE]
 > Docker Desktop on Linux, macOS, and Windows 10 does not currently provide KVM access to containers and is therefore not supported.

src/check.sh

@@ -15,12 +15,16 @@ file="/run/shm/dsm.url"
 address="/run/shm/qemu.ip"
 gateway="/run/shm/qemu.gw"
 
-[ ! -s  "$file" ] && echo "DSM has not enabled networking yet..." && exit 1
+# dsm.url is written only after the guest agent reports both the DSM
+# address and its configured HTTP port.
+[ ! -s  "$file" ] && echo "DSM has not enabled networking yet..." && exit 0
 
 location=$(<"$file")
 
 if ! curl -m 20 -ILfSs "http://$location/" > /dev/null; then
 
+  # In DHCP mode the firewall must allow the container address; with port
+  # forwarding it must allow the internal gateway used to reach the guest.
   if enabled "$DHCP"; then
     ip=$(<"$address")
     echo "Failed to reach DSM at http://$location"

src/config.sh

@@ -2,15 +2,73 @@
 set -Eeuo pipefail
 
 DEF_OPTS="-nodefaults -boot strict=on"
-RAM_OPTS=$(echo "-m ${RAM_SIZE^^}" | sed 's/MB/M/g;s/GB/G/g;s/TB/T/g')
-MON_OPTS="-name $PROCESS,process=$PROCESS,debug-threads=on -pidfile $QEMU_PID"
-CPU_OPTS="-cpu $CPU_FLAGS -smp $CPU_CORES,sockets=1,dies=1,cores=$CPU_CORES,threads=1"
-MAC_OPTS="-machine type=q35,smm=off,usb=off,vmport=off,dump-guest-core=off,hpet=off${KVM_OPTS}"
-DEV_OPTS="-device virtio-balloon-pci,id=balloon0,bus=pcie.0,addr=0x4"
-DEV_OPTS+=" -object rng-random,id=objrng0,filename=/dev/urandom"
-DEV_OPTS+=" -device virtio-rng-pci,rng=objrng0,id=rng0,bus=pcie.0,addr=0x1c"
+DEV_OPTS=""
 
-ARGS="$DEF_OPTS $CPU_OPTS $RAM_OPTS $MAC_OPTS $DISPLAY_OPTS $MON_OPTS $SERIAL_OPTS $NET_OPTS $DISK_OPTS $DEV_OPTS $ARGUMENTS"
-ARGS=$(echo "$ARGS" | sed 's/\t/ /g' | tr -s ' ')
+configureProcessor() {
+
+  # Expose one thread per core in a single socket; DSM licensing and topology
+  # reporting are more predictable with this fixed layout.
+  CPU_OPTS="-cpu $CPU_FLAGS"
+  CPU_OPTS+=" -smp $CPU_CORES,sockets=1,dies=1,cores=$CPU_CORES,threads=1"
+
+  return 0
+}
+
+configureMemory() {
+
+  RAM_OPTS=$(echo "-m ${RAM_SIZE^^}" | sed 's/MB/M/g;s/GB/G/g;s/TB/T/g')
+
+  return 0
+}
+
+configureMonitor() {
+
+  MON_OPTS="-name $PROCESS,process=$PROCESS,debug-threads=on"
+  MON_OPTS+=" -pidfile $QEMU_PID"
+
+  return 0
+}
+
+configureMachine() {
+
+  # Disable firmware and chipset features that Virtual DSM does not use and
+  # that can introduce extra devices or timing differences.
+  MAC_OPTS="-machine type=$MACHINE,smm=off,usb=off"
+  MAC_OPTS+=",vmport=off,dump-guest-core=off,hpet=off${KVM_OPTS}"
+
+  return 0
+}
+
+configureVirtioDevices() {
+
+  local bus
+  bus=$(getPciBus)
+
+  DEV_OPTS="-device virtio-balloon-pci,id=balloon0,bus=$bus,addr=0x4"
+  DEV_OPTS+=" -object rng-random,id=objrng0,filename=/dev/urandom"
+  DEV_OPTS+=" -device virtio-rng-pci,rng=objrng0,id=rng0,bus=$bus,addr=0x1c"
+
+  return 0
+}
+
+buildArguments() {
+
+  ARGS="$DEF_OPTS $CPU_OPTS $RAM_OPTS $MAC_OPTS $DISPLAY_OPTS $MON_OPTS $SERIAL_OPTS $NET_OPTS $DISK_OPTS $DEV_OPTS $ARGUMENTS"
+  # Collapse whitespace after optional argument groups are assembled so empty
+  # features cannot leave malformed spacing in the final QEMU command.
+  ARGS=$(echo "$ARGS" | sed 's/\t/ /g' | tr -s ' ')
+
+  return 0
+}
+
+finalizeMemory
+
+configureMemory
+configureMonitor
+configureMachine
+configureProcessor
+configureVirtioDevices
+
+buildArguments
 
 return 0

src/display.sh

@@ -6,19 +6,30 @@ set -Eeuo pipefail
 : "${GPU:="N"}"         # GPU passthrough
 : "${VGA:="virtio"}"    # VGA adaptor
 : "${DISPLAY:="none"}"  # Display type
+: "${LOSSY:="N"}"       # Lossy VNC compression
 : "${RENDERNODE:="/dev/dri/renderD128"}"  # Render node
 
 # Sanitize variables
 VGA=$(strip "$VGA")
+LOSSY=$(strip "$LOSSY")
 DISPLAY=$(strip "$DISPLAY")
 RENDERNODE=$(strip "$RENDERNODE")
 
 CPU_VENDOR=$(lscpu | awk '/Vendor ID/{print $3}')
 
-if ! enabled "$GPU" || [[ "$CPU_VENDOR" != "GenuineIntel" || "$ARCH" != "amd64" ]]; then
+# The accelerated Intel render-node path is restricted to x86 Intel hosts;
+# other platforms retain the normal QEMU display backend.
+if ! enabled "$GPU" || isAmdCpu || [[ "$ARCH" != "amd64" ]]; then
 
+  # A disabled frontend also removes the emulated VGA device to keep the guest
+  # hardware layout headless.
   [[ "${DISPLAY,,}" == "none" ]] && VGA="none"
-  DISPLAY_OPTS="-display $DISPLAY -vga $VGA"
+
+  if enabled "$LOSSY" && [[ "${DISPLAY,,}" == vnc=* ]]; then
+    DISPLAY+=",lossy=on"
+  fi
+
+  DISPLAY_OPTS="-display ${DISPLAY} -vga ${VGA}"
   return 0
 
 fi
@@ -27,12 +38,14 @@ msg="Configuring display drivers..."
 html "$msg"
 enabled "$DEBUG" && echo "$msg"
 
-DISPLAY_OPTS="-display egl-headless,rendernode=$RENDERNODE"
+DISPLAY_OPTS="-display egl-headless,rendernode=${RENDERNODE}"
 DISPLAY_OPTS+=" -vga $VGA"
 
 [ ! -d /dev/dri ] && mkdir -m 755 /dev/dri
 
 # Extract the card number from the render node
+# Linux renderD128 corresponds to card0; derive both device minors because
+# container device bindings may expose only the render node.
 CARD_NUMBER=$(echo "$RENDERNODE" | grep -oP '(?<=renderD)\d+')
 CARD_DEVICE="/dev/dri/card$((CARD_NUMBER - 128))"
 
@@ -48,6 +61,12 @@ if [ ! -c "$RENDERNODE" ]; then
   fi
 fi
 
+if [ ! -c "$RENDERNODE" ] || [ ! -r "$RENDERNODE" ] || [ ! -w "$RENDERNODE" ]; then
+  warn "render device '${RENDERNODE}' is unavailable or inaccessible."
+fi
+
+# Install acceleration packages lazily so non-GPU deployments keep the base
+# image small and do not require OpenGL modules.
 addPackage "xserver-xorg-video-intel" "Intel GPU drivers"
 addPackage "qemu-system-modules-opengl" "OpenGL module"
 

src/entry.sh

@@ -9,7 +9,8 @@ cd /run
 
 . start.sh      # Startup hook
 . utils.sh      # Load functions
-. reset.sh      # Initialize system
+. init.sh       # Initialize system
+. memory.sh     # Check memory
 . server.sh     # Start webserver
 . install.sh    # Run installation
 . disk.sh       # Initialize disks
@@ -18,7 +19,6 @@ cd /run
 . proc.sh       # Initialize processor
 . serial.sh     # Initialize serialport
 . power.sh      # Configure shutdown
-. memory.sh     # Check available memory
 . config.sh     # Configure arguments
 . finish.sh     # Finish initialization
 
@@ -32,14 +32,17 @@ if ! enabled "$SHUTDOWN"; then
   exec "${cmd[@]}" ${ARGS:+ $ARGS}
 fi
 
-if [ ! -t 1 ] || [ ! -c /dev/tty ]; then
+if ! interactive; then
   "${cmd[@]}" ${ARGS:+ $ARGS} &
 else
-  "${cmd[@]}" ${ARGS:+ $ARGS} </dev/tty >/dev/tty &
+  startConsole
+  startQemu "${cmd[@]}" ${ARGS:+ $ARGS}
 fi
 
+pid=$!
 rc=0
-wait $! || rc=$?
+
+wait "$pid" || rc=$?
 [ -f "$QEMU_END" ] && exit "$rc"
 
 sleep 1 & wait $!

src/finish.sh

@@ -2,7 +2,10 @@
 set -Eeuo pipefail
 
 if enabled "$DEBUG"; then
-  printf "QEMU arguments:\n\n%s\n\n" "${ARGS// -/$'\n-'}"
+  printf "QEMU arguments:\n\n    %s\n\n" "${ARGS// -/$'\n    -'}"
 fi
 
+# Must always remain the very last command
+enableTrap
+
 return 0

src/init.sh

@@ -13,6 +13,7 @@ enabled "${TRACE:-}" && set -o functrace && trap 'echo "# $BASH_COMMAND" >&2' DE
 : "${KVM:="Y"}"            # KVM acceleration
 : "${DEBUG:="N"}"          # Disable debugging mode
 : "${COUNTRY:=""}"         # Country code for mirror
+: "${MACHINE:="q35"}"      # Machine type selection
 : "${ALLOCATE:=""}"        # Preallocate diskspace
 : "${ARGUMENTS:=""}"       # Extra QEMU parameters
 : "${CPU_CORES:="2"}"      # Amount of CPU cores
@@ -40,8 +41,10 @@ detectEngine() {
 
 detectRootless() {
 
-  local uid_map=""
+  local uid_map
 
+  # A full identity UID map indicates a rootful container; any remapping is
+  # treated as rootless even though the process itself runs as UID 0.
   uid_map=$(awk '{$1=$1; print}' /proc/self/uid_map 2>/dev/null || true)
 
   if [[ "$uid_map" == "0 0 4294967295" ]]; then
@@ -57,8 +60,6 @@ checkPrivileged() {
 
   local cap_bnd
   local last_cap
-  local max_cap
-
   # Get the capability bounding set
   cap_bnd=$(grep '^CapBnd:' /proc/$$/status | awk '{print $2}')
   cap_bnd=$(printf "%d" "0x${cap_bnd}")
@@ -67,7 +68,9 @@ checkPrivileged() {
   last_cap=$(cat /proc/sys/kernel/cap_last_cap)
 
   # Calculate the maximum capability value
-  max_cap=$(((1 << (last_cap + 1)) - 1))
+  # Compare the bounding set with every capability supported by this kernel;
+  # checking only a few known capabilities would misclassify newer kernels.
+  local max_cap=$(((1 << (last_cap + 1)) - 1))
 
   if [ "$cap_bnd" -eq "$max_cap" ]; then
     PRIVILEGED="Y"
@@ -76,15 +79,15 @@ checkPrivileged() {
   return 0
 }
 
-normalizeCpuCores() {
+checkCores() {
 
   CPU_CORES=$(strip "$CPU_CORES")
   [ -z "$CPU_CORES" ] && CPU_CORES=2
   [[ "${CPU_CORES,,}" == "max" ]] && CPU_CORES="$CORES"
   [[ "${CPU_CORES,,}" == "half" ]] && CPU_CORES=$(( CORES / 2 ))
   [ -z "${CPU_CORES##*[!0-9]*}" ] && error "Invalid amount of CPU_CORES: $CPU_CORES" && exit 15
-
   [ "$CPU_CORES" -lt "1" ] && CPU_CORES=1
+
   if [ "$CPU_CORES" -gt "$CORES" ]; then
     warn "The amount for CPU_CORES (${CPU_CORES}) exceeds the amount of logical cores available (${CORES}) and will be limited."
     CPU_CORES="$CORES"
@@ -93,6 +96,20 @@ normalizeCpuCores() {
   return 0
 }
 
+checkSockets() {
+
+  local lscpu_out
+  lscpu_out=$(lscpu 2>/dev/null || true)
+
+  if grep -qi "socket(s)" <<< "$lscpu_out"; then
+    SOCKETS=$(grep -m 1 -i 'socket(s)' <<< "$lscpu_out" | awk '{print $2}')
+    [ -z "${SOCKETS##*[!0-9]*}" ] && SOCKETS=1
+    [ "$SOCKETS" -lt "1" ] && SOCKETS=1
+  fi
+
+  return 0
+}
+
 checkStorage() {
 
   # Check system
@@ -102,6 +119,8 @@ checkStorage() {
   if [ ! -d "/dev/shm" ]; then
     error "Directory /dev/shm not found!" && exit 14
   else
+    # Keep runtime sockets and PID files on shared memory even on images where
+    # /run/shm is absent but /dev/shm is available.
     [ ! -d "$QEMU_DIR" ] && ln -s /dev/shm "$QEMU_DIR"
   fi
 
@@ -110,7 +129,9 @@ checkStorage() {
   # Check folder
 
   if [[ "${STORAGE,,}" != "/storage" ]]; then
-    mkdir -p "$STORAGE"
+    if ! mkdir -p -- "$STORAGE"; then
+      error "Cannot create storage folder ($STORAGE)!" && exit 13
+    fi
   fi
 
   if [ ! -d "$STORAGE" ]; then
@@ -126,11 +147,9 @@ checkStorage() {
   return 0
 }
 
-checkFilesystem() {
+checkHost() {
 
   # Check filesystem
-  FS=$(stat -f -c %T "$STORAGE")
-
   if [[ "${FS,,}" == "ecryptfs" || "${FS,,}" == "tmpfs" ]]; then
     DISK_IO="threads"
     DISK_CACHE="writeback"
@@ -139,91 +158,6 @@ checkFilesystem() {
   return 0
 }
 
-finiteMemoryLimit() {
-
-  local limit="$1"
-  local sentinel="4611686018427387904"
-  local i=0
-  local left=""
-  local right=""
-
-  [[ "$limit" =~ ^[0-9]+$ ]] || return 1
-
-  (( ${#limit} < ${#sentinel} )) && return 0
-  (( ${#limit} > ${#sentinel} )) && return 1
-
-  for (( i=0; i<${#sentinel}; i++ )); do
-    left="${limit:i:1}"
-    right="${sentinel:i:1}"
-
-    (( left < right )) && return 0
-    (( left > right )) && return 1
-  done
-
-  return 1
-}
-
-getMemoryInfo() {
-
-  local host_total=""
-  local host_avail=""
-  local limit=""
-  local current=""
-  local available=""
-
-  host_total=$(free -b | awk '/^Mem:/ {print $2; exit}')
-  host_avail=$(free -b | awk '/^Mem:/ {print $7; exit}')
-
-  RAM_TOTAL="$host_total"
-  RAM_AVAIL="$host_avail"
-
-  if [ -r /sys/fs/cgroup/memory.max ] && [ -r /sys/fs/cgroup/memory.current ]; then
-    limit=$(< /sys/fs/cgroup/memory.max)
-    current=$(< /sys/fs/cgroup/memory.current)
-  elif [ -r /sys/fs/cgroup/memory/memory.limit_in_bytes ] && [ -r /sys/fs/cgroup/memory/memory.usage_in_bytes ]; then
-    limit=$(< /sys/fs/cgroup/memory/memory.limit_in_bytes)
-    current=$(< /sys/fs/cgroup/memory/memory.usage_in_bytes)
-  fi
-
-  if finiteMemoryLimit "$limit" && [[ "$current" =~ ^[0-9]+$ ]]; then
-    (( limit < RAM_TOTAL )) && RAM_TOTAL="$limit"
-
-    available=$(( limit - current ))
-    (( available < 0 )) && available=0
-    (( available < RAM_AVAIL )) && RAM_AVAIL="$available"
-  fi
-
-  return 0
-}
-
-normalizeRamSize() {
-
-  # Read host and container memory limits.
-  getMemoryInfo
-
-  RAM_SPARE=500000000
-  RAM_MINIMUM=136314880
-
-  RAM_SIZE=$(strip "$RAM_SIZE")
-  RAM_SIZE="${RAM_SIZE// /}"
-  [ -z "$RAM_SIZE" ] && RAM_SIZE="2G"
-
-  if [[ "${RAM_SIZE,,}" != "max" && "${RAM_SIZE,,}" != "half" ]]; then
-
-    if [ -z "${RAM_SIZE//[0-9. ]}" ]; then
-      [ "${RAM_SIZE%%.*}" -lt "130" ] && RAM_SIZE="${RAM_SIZE}G" || RAM_SIZE="${RAM_SIZE}M"
-    fi
-
-    RAM_SIZE=$(echo "${RAM_SIZE^^}" | sed 's/MB/M/g;s/GB/G/g;s/TB/T/g')
-    ! numfmt --from=iec "$RAM_SIZE" &>/dev/null && error "Invalid RAM_SIZE: $RAM_SIZE" && exit 16
-    wanted=$(numfmt --from=iec "$RAM_SIZE")
-    [ "$wanted" -lt "$RAM_MINIMUM" ] && error "RAM_SIZE is too low: $RAM_SIZE" && exit 16
-
-  fi
-
-  return 0
-}
-
 checkKvm() {
 
   # Check KVM support
@@ -237,6 +171,8 @@ checkKvm() {
   if disabled "$KVM"; then
     warn "KVM acceleration is disabled, this will cause the machine to run about 10 times slower!"
   else
+    # KVM accelerates only matching host and guest instruction sets; cross-
+    # architecture execution must fall back to software emulation.
     if [[ "${ARCH,,}" != "$TARGET" ]]; then
       KVM="N"
       warn "your CPU architecture is ${ARCH^^} and cannot provide KVM acceleration for ${PLATFORM^^} instructions, so the machine will run about 10 times slower."
@@ -260,7 +196,7 @@ checkKvm() {
           fi
           if ! grep -qw "sse4_2" <<< "$flags"; then
             error "Your CPU does not have the SSE4 instruction set that Virtual DSM requires!"
-            ! enabled "$DEBUG" && exit 88
+            enabled "$DEBUG" || exit 88
           fi
         fi
       fi
@@ -281,7 +217,7 @@ checkKvm() {
             error "KVM acceleration is not available $KVM_ERR, this will cause the machine to run about 10 times slower."
             error "See the FAQ for possible causes, or disable acceleration by adding the \"KVM=N\" variable (not recommended)." ;;
         esac
-        ! enabled "$DEBUG" && exit 88
+        enabled "$DEBUG" || exit 88
       fi
     fi
 
@@ -294,6 +230,7 @@ checkKvm() {
 TZ=$(strip "$TZ")
 STORAGE=$(strip "$STORAGE")
 COUNTRY=$(strip "$COUNTRY")
+MACHINE=$(strip "${MACHINE,,}")
 DISK_SIZE=$(strip "$DISK_SIZE")
 
 # Helper variables
@@ -320,24 +257,18 @@ FOOTER2="<a href='$SUPPORT'>$SUPPORT</a>"
 SOCKETS=1
 CPU=$(cpu)
 SYS=$(uname -r)
-KERNEL=$(echo "$SYS" | cut -b 1)
-MINOR=$(echo "$SYS" | cut -d '.' -f2)
 ARCH=$(dpkg --print-architecture)
 CORES=$(grep -c '^processor' /proc/cpuinfo)
+IFS=. read -r KERNEL MINOR _ <<< "$SYS"
 
-if grep -qi "socket(s)" <<< "$(lscpu)"; then
-  SOCKETS=$(lscpu | grep -m 1 -i 'socket(s)' | awk '{print $2}')
-  [ -z "${SOCKETS##*[!0-9]*}" ] && SOCKETS=1
-  [ "$SOCKETS" -lt "1" ] && SOCKETS=1
-fi
-
-normalizeCpuCores
+checkSockets
+checkCores
 checkStorage
-checkFilesystem
-normalizeRamSize
+getMemoryInfo
 
 # Print system info
 SYS="${SYS/-generic/}"
+FS=$(stat -f -c %T "$STORAGE")
 FS="${FS/UNKNOWN //}"
 FS="${FS/ext2\/ext3/ext4}"
 FS=$(echo "$FS" | sed 's/[)(]//g')
@@ -349,11 +280,14 @@ TOTAL_MEM=$(formatBytes "$RAM_TOTAL" "up")
 echo "❯ CPU: ${CPU} | RAM: ${AVAIL_MEM/ GB/}/$TOTAL_MEM | DISK: $SPACE_GB (${FS}) | KERNEL: ${SYS}"
 echo
 
+checkHost
 checkKvm
 
+# Runtime state is intentionally discarded at each container start; persistent
+# machine and disk identity lives under STORAGE instead.
 # Cleanup files
 rm -f "$QEMU_DIR"/dsm.url
-rm -f "$QEMU_DIR"/qemu.* "$QEMU_DIR"/*.pid "$QEMU_DIR"/*.sock
+rm -f "$QEMU_DIR"/{qemu.*,*.{pid,sock,pipe}}
 
 # Cleanup dirs
 rm -rf /tmp/dsm

src/install.sh

@@ -3,6 +3,8 @@ set -Eeuo pipefail
 
 : "${URL:=""}"    # URL of the PAT file to be downloaded.
 
+# Persist the exact PAT base name so future starts reopen the matching boot,
+# system, and cached installation files.
 if [ -f "$STORAGE/dsm.ver" ]; then
   BASE=$(<"$STORAGE/dsm.ver")
   BASE="${BASE//[![:print:]]/}"
@@ -16,6 +18,8 @@ FN="boot.pat"
 DIR=$(find / -maxdepth 1 -type d -iname "$FN" -print -quit)
 [ ! -d "$DIR" ] && DIR=$(find "$STORAGE" -maxdepth 1 -type d -iname "$FN" -print -quit)
 
+# A boot.pat directory bind represents already extracted boot and system
+# images and therefore takes precedence over PAT file or URL discovery.
 if [ -d "$DIR" ]; then
   BASE="DSM_VirtualDSM" && URL="file://$DIR"
   if [[ ! -s "$STORAGE/$BASE.boot.img" || ! -s "$STORAGE/$BASE.system.img" ]]; then
@@ -29,6 +33,8 @@ FILE=$(find / -maxdepth 1 -type f -iname "$FN" -print -quit)
 
 URL=$(strip "$URL")
 
+# Derive a filesystem-safe identity from the URL only when no local boot.pat
+# source was supplied; preserve an existing system image identity if present.
 if [ -n "$URL" ] && [ ! -s "$FILE" ] && [ ! -d "$DIR" ]; then
   BASE=$(basename "$URL" .pat)
   if [ ! -s "$STORAGE/$BASE.system.img" ]; then
@@ -42,6 +48,8 @@ if [ -n "$URL" ] && [ ! -s "$FILE" ] && [ ! -d "$DIR" ]; then
   fi
 fi
 
+# A complete matching image pair is the installation marker; the cached PAT
+# itself is optional after installation.
 if [[ -s "$STORAGE/$BASE.boot.img" && -s "$STORAGE/$BASE.system.img" ]]; then
   return 0  # Previous installation found
 fi
@@ -55,6 +63,8 @@ DL_GLOBAL="https://global.synologydownload.com/download/DSM"
 [[ "${URL,,}" == *"cndl.synology"* ]] && DL="$DL_CHINA"
 [[ "${URL,,}" == *"global.synology"* ]] && DL="$DL_GLOBAL"
 
+# Honor an explicitly selected Synology mirror first, otherwise choose the
+# China or global endpoint from the detected country.
 if [ -z "$DL" ]; then
   [ -z "$COUNTRY" ] && setCountry
   [ -z "$COUNTRY" ] && info "Warning: could not detect country to select mirror!"
@@ -98,6 +108,8 @@ if [[ "${FS,,}" == "fat"* || "${FS,,}" == "vfat"* || "${FS,,}" == "msdos"* ]]; t
   error "Unable to install on $FS filesystems, please use a different filesystem for /storage." && exit 61
 fi
 
+# Extract beside storage on Unix filesystems to avoid container-space limits;
+# use /tmp for filesystems that cannot safely host the installer workspace.
 if [[ "${FS,,}" != "exfat"* && "${FS,,}" != "ntfs"* && "${FS,,}" != "unknown"* ]]; then
   TMP="$STORAGE/tmp"
   rm -rf "$TMP"
@@ -126,13 +138,6 @@ SPACE=$(df --output=avail -B 1 "$STORAGE" | tail -n 1)
 SPACE_GB=$(formatBytes "$SPACE")
 (( MIN_SPACE > SPACE )) && error "Not enough free space for installation in $STORAGE, have $SPACE_GB available but need at least 14 GB." && exit 94
 
-# Check if output is to interactive TTY
-if [ -t 1 ]; then
-  PROGRESS="--progress=bar:noscroll"
-else
-  PROGRESS="--progress=dot:giga"
-fi
-
 if [[ "$URL" == "file://"* ]]; then
   MSG="Copying DSM"
   ERR="Failed to copy ${URL:7}"
@@ -160,17 +165,26 @@ else
 
   SIZE=0
   REASON=""
+  PROGRESS=()
+  OUTPUT=""
   LOG=$(mktemp)
 
   [[ "${URL,,}" == *"_72806.pat" ]] && SIZE=361010261
   [[ "${URL,,}" == *"_69057.pat" ]] && SIZE=363837333
   [[ "${URL,,}" == *"_42218.pat" ]] && SIZE=379637760
 
-  /run/progress.sh "$PAT" "$SIZE" "$MSG ([P])..." &
+  # Use Wget's progress bar in a terminal and progress.sh in container logs.
+  if [ -t 1 ]; then
+    PROGRESS=( --show-progress --progress=bar:noscroll )
+  else
+    OUTPUT="log"
+  fi
+
+  /run/progress.sh "$PAT" "$SIZE" "$MSG ([P])..." "$OUTPUT" 52428800 &
 
   {
     LC_ALL=C wget "$URL" -O "$PAT" --no-verbose --no-check-certificate \
-      --timeout=30 --no-http-keep-alive --show-progress "$PROGRESS" \
+      --timeout=30 --no-http-keep-alive "${PROGRESS[@]}" \
       --output-file="$LOG"
     rc=$?
   } || :
@@ -204,6 +218,8 @@ fi
 
 SIZE=$(stat -c%s "$PAT")
 
+# Full Virtual DSM PAT files are substantially larger than update packs;
+# reject undersized inputs before attempting destructive image preparation.
 if ((SIZE<250000000)); then
   error "The specified PAT file is probably an update pack as it's too small." && exit 62
 fi
@@ -211,6 +227,8 @@ fi
 MSG="Extracting installation image..."
 info "Install: $MSG" && html "$MSG"
 
+# Newer PAT files are normal tar archives; older encrypted/proprietary forms
+# require the bundled extractor as a compatibility fallback.
 if { tar tf "$PAT"; } >/dev/null 2>&1; then
 
   tar xpf "$PAT" -C "$TMP/."
@@ -229,6 +247,8 @@ fi
 MSG="Preparing system partition..."
 info "Install: $MSG" && html "$MSG"
 
+# The PAT boot archive becomes the persistent QEMU boot disk after its
+# companion system partition has been assembled.
 BOOT=$(find "$TMP" -name "*.bin.zip" -print -quit)
 [ -z "$BOOT" ] && error "The PAT file contains no boot image." && exit 67
 [ ! -s "$BOOT" ] && error "The PAT boot image archive is empty." && exit 67
@@ -252,7 +272,7 @@ if ! touch "$SYSTEM"; then
   error "Could not create file $SYSTEM for the system disk." && exit 98
 fi
 
-! setOwner "$SYSTEM" && warn "failed to set the owner for \"$SYSTEM\" !"
+setOwner "$SYSTEM" || warn "failed to set the owner for \"$SYSTEM\" !"
 
 if [[ "${FS,,}" == "btrfs" ]]; then
   { chattr +C "$SYSTEM"; } || :
@@ -271,6 +291,8 @@ if ! fallocate -l "$SYSTEM_SIZE" "$SYSTEM" &>/dev/null; then
   fi
 fi
 
+# Recreate Synology's expected DOS partition layout inside the fixed 10 GiB
+# system image before populating the ext4 root partition.
 PART="$TMP/partition.fdisk"
 
 {
@@ -318,6 +340,8 @@ OFFSET="1048576"    # 2048 * 512
 NUMBLOCKS="2097152" # (16777216 * 512) / 4096
 MSG="Installing system partition..."
 
+# Build the ext4 filesystem directly from the extracted tree under fakeroot,
+# preserving archive ownership without mounting a loop device.
 fakeroot -- bash -c "set -Eeu;\
   [ -s $HDP.txz ] && tar xpfJ $HDP.txz --absolute-names -C $MOUNT/;\
   [ -s $IDB.txz ] && tar xpfJ $IDB.txz --absolute-names -C $INDEX_DB/;\
@@ -327,8 +351,10 @@ fakeroot -- bash -c "set -Eeu;\
 
 rm -rf "$MOUNT"
 echo "$BASE" > "$STORAGE/dsm.ver"
-! setOwner "$STORAGE/dsm.ver" && warn "failed to set the owner for \"$STORAGE/dsm.ver\" !"
+setOwner "$STORAGE/dsm.ver" || warn "failed to set the owner for \"$STORAGE/dsm.ver\" !"
 
+# Do not keep a second copy when the source PAT already lives in storage;
+# downloaded or externally mounted sources are cached for later reuse.
 if [[ "$URL" == "file://$STORAGE/$BASE.pat" ]]; then
   rm -f "$PAT"
 else
@@ -336,11 +362,11 @@ else
 fi
 
 if [ -f "$STORAGE/$BASE.pat" ]; then
-  ! setOwner "$STORAGE/$BASE.pat" && warn "failed to set the owner for \"$STORAGE/$BASE.pat\" !"
+  setOwner "$STORAGE/$BASE.pat" || warn "failed to set the owner for \"$STORAGE/$BASE.pat\" !"
 fi
 
 mv -f "$BOOT" "$STORAGE/$BASE.boot.img"
-! setOwner "$STORAGE/$BASE.boot.img" && warn "failed to set the owner for \"$STORAGE/$BASE.boot.img\" !"
+setOwner "$STORAGE/$BASE.boot.img" || warn "failed to set the owner for \"$STORAGE/$BASE.boot.img\" !"
 
 rm -rf "$TMP"
 

src/memory.sh

@@ -1,77 +1,144 @@
 #!/usr/bin/env bash
 set -Eeuo pipefail
 
-msg="Checking memory..."
-enabled "$DEBUG" && echo "$msg"
+normalizeMemory() {
+
+  local wanted
+
+  RAM_SPARE=500000000
+  RAM_MINIMUM="${RAM_MINIMUM:-1073741824}"
+
+  RAM_MINIMUM=$(strip "$RAM_MINIMUM")
+  RAM_MINIMUM="${RAM_MINIMUM// /}"
+  RAM_MINIMUM=$(echo "${RAM_MINIMUM^^}" | sed 's/MB/M/g;s/GB/G/g;s/TB/T/g')
+  numfmt --from=iec "$RAM_MINIMUM" &>/dev/null || {
+    error "Invalid RAM_MINIMUM: $RAM_MINIMUM"
+    exit 16
+  }
+  RAM_MINIMUM=$(numfmt --from=iec "$RAM_MINIMUM")
+
+  RAM_SIZE=$(strip "$RAM_SIZE")
+  RAM_SIZE="${RAM_SIZE// /}"
+  [ -z "$RAM_SIZE" ] && RAM_SIZE="2G"
+
+  if [[ "${RAM_SIZE,,}" != "max" && "${RAM_SIZE,,}" != "half" ]]; then
+
+    # Bare values below 130 are interpreted as GiB for convenience; larger bare
+    # values are treated as MiB to preserve historical configurations.
+    if [ -z "${RAM_SIZE//[0-9. ]}" ]; then
+      [ "${RAM_SIZE%%.*}" -lt "130" ] && RAM_SIZE="${RAM_SIZE}G" || RAM_SIZE="${RAM_SIZE}M"
+    fi
+
+    RAM_SIZE=$(echo "${RAM_SIZE^^}" | sed 's/MB/M/g;s/GB/G/g;s/TB/T/g')
+    numfmt --from=iec "$RAM_SIZE" &>/dev/null || {
+      error "Invalid RAM_SIZE: $RAM_SIZE"
+      exit 16
+    }
+
+    wanted=$(numfmt --from=iec "$RAM_SIZE")
+
+    if [ "$wanted" -lt "$RAM_MINIMUM" ]; then
+      error "$(app) requires at least $(formatBytes "$RAM_MINIMUM") of RAM, but RAM_SIZE is set to $(formatBytes "$wanted")."
+      exit 16
+    fi
+
+    # QEMU requires a whole-number memory value, so convert decimal sizes to MiB.
+    if [[ "$RAM_SIZE" == *.* ]]; then
+      RAM_SIZE="$(( wanted / 1048576 ))M"
+    fi
+
+  fi
 
-app() {
-  echo "Virtual DSM"
   return 0
 }
 
 checkConfiguredMemory() {
-  local wanted msg
+
+  local final="$1"
 
   if disabled "$RAM_CHECK" || [[ "${RAM_SIZE,,}" == "max" || "${RAM_SIZE,,}" == "half" ]]; then
     return 0
   fi
 
+  local wanted avail_mem
   wanted=$(numfmt --from=iec "$RAM_SIZE")
+  avail_mem=$(formatBytes "$RAM_AVAIL")
 
   if (( (wanted + RAM_SPARE) > RAM_AVAIL )); then
-    msg="Your configured RAM_SIZE of ${RAM_SIZE/G/ GB} is too high for the $AVAIL_MEM of free memory available,"
+
+    local msg="Your configured RAM_SIZE of ${RAM_SIZE/G/ GB} is too high for the $avail_mem of free memory available,"
+
+    # ZFS ARC can release cached memory under pressure, so this free-memory
+    # heuristic remains informational instead of rewriting RAM_SIZE.
     if [[ "${FS,,}" == "zfs" ]]; then
-      info "$msg but since ZFS is active this will be ignored."
+
+      enabled "$final" && info "$msg but since ZFS is active this will be ignored."
+
     else
+
       RAM_SIZE="max"
-      warn "$msg it will automatically be adjusted to a lower amount."
+      RAM_WARNING="$msg it will automatically be adjusted to a lower amount."
+
     fi
+
   else
+
     if (( (wanted + (RAM_SPARE * 3)) > RAM_AVAIL )); then
-      msg="your configured RAM_SIZE of ${RAM_SIZE/G/ GB} is very close to the $AVAIL_MEM of free memory available,"
+
+      local msg="your configured RAM_SIZE of ${RAM_SIZE/G/ GB} is very close to the $avail_mem of free memory available,"
+
       if [[ "${FS,,}" == "zfs" ]]; then
-        info "$msg but since ZFS is active this will be ignored."
+        enabled "$final" && info "$msg but since ZFS is active this will be ignored."
       else
-        warn "$msg please consider a lower amount."
+        enabled "$final" && warn "$msg please consider a lower amount."
       fi
+
     fi
+
   fi
 
   return 0
 }
 
 configureHalfMemory() {
-  local wanted
 
   if [[ "${RAM_SIZE,,}" != "half" ]]; then
     return 0
   fi
 
   if (( (RAM_AVAIL / 2) > RAM_SPARE )); then
-    wanted=$(( (RAM_AVAIL / 2) / 1048577 ))
-    RAM_SIZE="${wanted}M"
-    info "Allocated $wanted MB of RAM for $(app)."
+
+    local wanted=$(( RAM_AVAIL / 2 ))
+
+    # Divide by one byte more than a MiB to round down
+    local target=$(( wanted / 1048577 ))
+    RAM_SIZE="${target}M"
+    RAM_ALLOCATION="$wanted"
+
   else
+
     RAM_SIZE="max"
+
   fi
 
   return 0
 }
 
 configureMaxMemory() {
-  local wanted
 
   if [[ "${RAM_SIZE,,}" != "max" ]]; then
     return 0
   fi
 
+  # max keeps a host reserve when possible, but on very small systems falls back
+  # to half the available memory to avoid starving the container.
   if (( RAM_AVAIL < (RAM_SPARE * 2) )); then
 
-    wanted=$(( RAM_AVAIL / 2 ))
+    local wanted=$(( RAM_AVAIL / 2 ))
 
   else
 
-    wanted=$(( RAM_AVAIL - (RAM_SPARE * 3) ))
+    local wanted=$(( RAM_AVAIL - (RAM_SPARE * 3) ))
 
     if (( wanted < (RAM_SPARE * 6) )); then
       wanted=$(( RAM_AVAIL - RAM_SPARE ))
@@ -79,34 +146,90 @@ configureMaxMemory() {
 
   fi
 
-  wanted=$(( wanted / 1048577 ))
-  RAM_SIZE="${wanted}M"
+  # Divide by one byte more than a MiB to round down
+  local target=$(( wanted / 1048577 ))
+  RAM_SIZE="${target}M"
+  RAM_ALLOCATION="$wanted"
 
-  info "Allocated $wanted MB of RAM for $(app)."
+  return 0
+}
+
+showMemoryLimitHint() {
+
+  local kernel
+  kernel=$(uname -r)
+
+  if [[ "${kernel,,}" == *-wsl2* ]]; then
+    echo
+    info "Docker Desktop (WSL2) is detected, follow these instructions:"
+    info ""
+    info "Increase the memory limit in \"%UserProfile%\\.wslconfig\" by setting \"memory=<size>\" under \"[wsl2]\"."
+    info "Then run \"wsl --shutdown\" in PowerShell and restart Docker Desktop for the new limit to take effect."
+    echo
+  fi
 
   return 0
 }
 
 checkMinimumMemory() {
-  local wanted
 
+  local wanted
   wanted=$(numfmt --from=iec "$RAM_SIZE")
 
   if [ "$wanted" -lt "$RAM_MINIMUM" ]; then
-    wanted=$(( wanted / 1048577 ))
-    error "Not enough memory available, there is only $wanted MB left!"
+
+    error "$(app) requires at least $(formatBytes "$RAM_MINIMUM") of RAM, but only $(formatBytes "$wanted") can be allocated."
+
+    showMemoryLimitHint
+
     exit 16
   fi
 
   return 0
 }
 
-getMemoryInfo
-AVAIL_MEM=$(formatBytes "$RAM_AVAIL")
+checkMemoryAllocation() {
 
-checkConfiguredMemory
-configureHalfMemory
-configureMaxMemory
-checkMinimumMemory
+  local final="${1:-N}"
+  local configured
+
+  normalizeMemory
+  configured="$RAM_SIZE"
+
+  RAM_WARNING=""
+  RAM_ALLOCATION=""
+
+  getMemoryInfo
+  checkConfiguredMemory "$final"
+
+  configureHalfMemory
+  configureMaxMemory
+  checkMinimumMemory
+
+  if enabled "$final"; then
+    [ -n "$RAM_WARNING" ] && warn "$RAM_WARNING"
+    [ -n "$RAM_ALLOCATION" ] && info "Allocated $(formatBytes "$RAM_ALLOCATION") of RAM for $(app)."
+  else
+    RAM_SIZE="$configured"
+  fi
+
+  return 0
+}
+
+checkMemoryRequirement() {
+
+  checkMemoryAllocation "N"
+
+  return 0
+}
+
+finalizeMemory() {
+
+  checkMemoryAllocation "Y"
+
+  return 0
+}
+
+checkMemoryRequirement
 
 return 0

src/power.sh

@@ -2,25 +2,31 @@
 set -Eeuo pipefail
 
 : "${SHUTDOWN:="Y"}"        # Graceful ACPI shutdown
-: "${TIMEOUT:="115"}"       # QEMU termination timeout
+: "${TIMEOUT:="105"}"       # QEMU termination timeout
 : "${API_TIMEOUT:="90"}"    # External API call timeout
 
 # Configure QEMU for graceful shutdown
 
 API_CMD=6
-API_HOST="127.0.0.1:$COM_PORT"
 
-# Configure QEMU for graceful shutdown
+SHUTDOWN_SKIP=0
+SHUTDOWN_SIGNAL=0
 
 QEMU_END="$QEMU_DIR/qemu.end"
+CONSOLE_PID="$QEMU_DIR/console.pid"
+CONSOLE_SOCKET="$QEMU_DIR/console.sock"
+QEMU_START_PID="$QEMU_DIR/qemu.start.pid"
 
 _trap() {
 
   local func="$1"; shift
   local sig
+
   TRAP_PID=$BASHPID
 
   for sig; do
+    # Capture the local callback and signal while registering the trap.
+    # shellcheck disable=SC2064
     trap "$func $sig" "$sig"
   done
 
@@ -61,11 +67,40 @@ displayReason() {
 
 readQemuPid() {
 
-  local -n _pid="$1"
+  # Interactive startup uses a wrapper-created PID file before QEMU writes its
+  # own pidfile, so accept either during startup and shutdown races.
+  readPidFile "$1" "$QEMU_START_PID" && return 0
+  readPidFile "$1" "$QEMU_PID"
+}
 
-  if [ ! -s "$QEMU_PID" ] || ! read -r _pid <"$QEMU_PID"; then
-    return 1
-  fi
+qemuPidFile() {
+
+  local -n _file="$1"
+
+  _file="$QEMU_PID"
+  [ -s "$QEMU_START_PID" ] && _file="$QEMU_START_PID"
+
+  return 0
+}
+
+waitQemuExit() {
+
+  local timeout="${1:-10}"
+  local file
+
+  qemuPidFile file
+  waitPidFile "$file" "$timeout"
+}
+
+waitQemuPid() {
+
+  local cnt=0
+
+  while ! readQemuPid "$1"; do
+    sleep 0.02
+    cnt=$((cnt + 1))
+    (( cnt >= 50 )) && return 1
+  done
 
   return 0
 }
@@ -73,11 +108,10 @@ readQemuPid() {
 forceKillQemu() {
 
   local reason="$1"
-  local pid=""
-  local display
+  local pid display
 
-  ! readQemuPid pid && return 0
-  ! isAlive "$pid" && return 0
+  readQemuPid pid || return 0
+  isAlive "$pid" || return 0
 
   display=$(displayReason "$reason")
   error "Forcefully terminating $(app), reason: $display..."
@@ -88,29 +122,117 @@ forceKillQemu() {
 
 cleanupHelpers() {
 
-  local pids=( "${HOST_PID:-}" "${WSD_PID:-}" \
+  local pids=( "${HOST_PID:-}" "${WSD_PID:-}" "${CONSOLE_PID:-}" \
                "${WEB_PID:-}" "${PASST_PID:-}" "${DNSMASQ_PID:-}" )
 
   mKill "${pids[@]}"
   fKill "print.sh"
 
+  rm -f -- "$HOST_API_SOCKET" "$HOST_AGENT_SOCKET"
+
   closeNetwork
   return 0
 }
 
+startConsole() {
+
+  local output="${1:-/dev/tty}"
+  local cnt=0
+
+  rm -f -- "$CONSOLE_SOCKET" "$CONSOLE_PID"
+
+  if ! stty -icanon -echo isig -ixon min 1 time 0 </dev/tty; then
+    error "Failed to configure serial console terminal!"
+    return 1
+  fi
+
+  (
+    trap '' INT QUIT
+    exec nc -lU "$CONSOLE_SOCKET" </dev/tty >"$output"
+  ) &
+
+  local pid="$!"
+  echo "$pid" > "$CONSOLE_PID"
+
+  while [ ! -S "$CONSOLE_SOCKET" ]; do
+
+    if ! isAlive "$pid"; then
+      rm -f -- "$CONSOLE_PID"
+      error "Serial console relay exited unexpectedly!"
+      return 1
+    fi
+
+    sleep 0.02
+    cnt=$((cnt + 1))
+
+    if (( cnt > 100 )); then
+      error "Failed to start serial console relay!"
+      return 1
+    fi
+
+  done
+
+  return 0
+}
+
+stopConsole() {
+
+  mKill "$CONSOLE_PID"
+
+  return 0
+}
+
+startQemu() {
+
+  rm -f -- "$QEMU_START_PID"
+
+  # Launch QEMU in a separate session while recording the real child PID;
+  # setsid's wrapper PID is not suitable for guest shutdown or forced cleanup.
+  (
+    trap '' INT QUIT
+
+    # shellcheck disable=SC2016
+    exec setsid -f -w sh -c '
+      file=$1
+      shift
+
+      "$@" &
+      pid=$!
+      printf "%s\n" "$pid" > "$file" || exit 1
+
+      rc=0
+      wait "$pid" 2>/dev/null || rc=$?
+      exit "$rc"
+    ' sh "$QEMU_START_PID" "$@"
+  ) </dev/null &
+
+  return 0
+}
+
 finish() {
 
-  local reason=$1
+  local reason=$1 failed=0
+
+  if [ ! -f "$QEMU_END" ] && (( reason != 0 )); then
+    failed=1
+  fi
+
   touch "$QEMU_END"
 
   forceKillQemu "$reason"
   cleanupHelpers
 
-  if ! waitPidFile "$QEMU_PID" 10; then
+  if ! waitQemuExit 10; then
     warn "Timed out while waiting for $(app) to exit!"
   fi
 
-  (( reason != 1 )) && echo && echo "❯ Shutdown completed!"
+  echo
+
+  if (( failed == 0 )); then
+    echo "❯ Shutdown completed!"
+  else
+    error "QEMU exited unexpectedly!"
+  fi
 
   exit "$reason"
 }
@@ -119,15 +241,16 @@ sendGuestShutdown() {
 
   local pid="$1"
   local response
-  local url
 
+  # Virtual DSM ignores ACPI powerdown, so graceful shutdown must go through
+  # the qemu-host guest API exposed on the Unix socket.
   # Don't send the powerdown signal because vDSM ignores ACPI signals
   # nc -q 1 -w 1 -U "$QEMU_DIR/monitor.sock" &> /dev/null <<<'system_powerdown' || :
 
   # Send shutdown command to guest agent via serial port
   API_TIMEOUT=$(strip "$API_TIMEOUT")
-  url="http://$API_HOST/read?command=$API_CMD&timeout=$API_TIMEOUT"
-  response=$(curl -sk -m "$(( API_TIMEOUT+2 ))" -S "$url" 2>&1)
+  local url="http://localhost/read?command=$API_CMD&timeout=$API_TIMEOUT"
+  response=$(curl --unix-socket "$HOST_API_SOCKET" -sk -m "$(( API_TIMEOUT+2 ))" -S "$url" 2>&1)
 
   if [[ "$response" =~ "\"success\"" ]]; then
 
@@ -148,15 +271,14 @@ sendGuestShutdown() {
 
 normalizeTimeout() {
 
+  # Divide the remaining timeout into guest wait, SIGTERM grace, and final
+  # cleanup instead of allowing the API call to consume the entire budget.
   local term_grace=3      # seconds before loop ends to send SIGTERM
   local cleanup_grace=3   # seconds reserved after the loop for cleanup
-  local elapsed
-  local timeout_left
-  local min
 
   TIMEOUT=$(strip "$TIMEOUT")
   if [[ ! "$TIMEOUT" =~ ^[0-9]+$ ]]; then
-    TIMEOUT=115
+    TIMEOUT=105
   fi
 
   if (( TIMEOUT >= 30 )); then
@@ -167,10 +289,10 @@ normalizeTimeout() {
     cleanup_grace=4
   fi
 
-  elapsed=$((SECONDS - start))
-  timeout_left=$((TIMEOUT - elapsed))
+  local elapsed=$((SECONDS - start))
+  local timeout_left=$((TIMEOUT - elapsed))
 
-  min=$((term_grace + cleanup_grace + 1))
+  local min=$((term_grace + cleanup_grace + 1))
   (( timeout_left < min )) && timeout_left=$min
 
   wait_until=$((timeout_left - cleanup_grace))
@@ -184,18 +306,19 @@ waitForShutdown() {
   local cnt=0
   local pid="$1"
   local name="$APP"
-  local slp
 
-  while (( cnt <= wait_until )); do
+  while (( cnt <= wait_until && SHUTDOWN_SKIP == 0 )); do
 
     sleep 1 &
-    slp=$!
+    local slp=$!
 
     # Stop waiting if the process has exited
-    ! isAlive "$pid" && break
+    isAlive "$pid" || break
 
+    # The process state is authoritative, but disappearance of both pidfiles
+    # also ends the wait when a wrapper exits before process reaping completes.
     # Workaround for stale/zombie QEMU pid file
-    [ ! -s "$QEMU_PID" ] && break
+    [ ! -s "$QEMU_START_PID" ] && [ ! -s "$QEMU_PID" ] && break
 
     if (( cnt == sigterm_at )); then
       info "${name^} is still running, sending SIGTERM... ($cnt/$wait_until)"
@@ -204,7 +327,7 @@ waitForShutdown() {
       info "Waiting for $name to shut down... ($cnt/$wait_until)"
     fi
 
-    wait "$slp"
+    wait "$slp" || :
     (( cnt++ ))
 
   done
@@ -212,32 +335,47 @@ waitForShutdown() {
   return 0
 }
 
-graceful_shutdown() {
+gracefulShutdown() {
 
   local sig="$1"
-  local pid=""
-  local code=0
+  local pid code
 
   [[ $BASHPID != "$TRAP_PID" ]] && return
 
   code=$(signalCode "$sig")
 
-  if [ -f "$QEMU_END" ]; then
-    echo && info "Received $1 signal while already shutting down..."
+  if (( SHUTDOWN_SIGNAL != 0 )); then
+
+    # A second Ctrl-C is the explicit user request to skip the remaining
+    # graceful-shutdown wait and proceed to forced cleanup.
+    if (( code == 130 && SHUTDOWN_SIGNAL == code )); then
+      SHUTDOWN_SKIP=1
+      echo && info "Received SIGINT again, forcing shutdown..."
+      return
+    fi
+
+    echo && info "Received $sig signal while already shutting down..."
     return
   fi
 
-  set +e
   start=$SECONDS
+  SHUTDOWN_SIGNAL=$code
+
+  # Shutdown handlers must continue through missing processes and failed cleanup
+  # commands instead of being aborted by errexit.
+  set +e
   touch "$QEMU_END"
-  echo && info "Received $1 signal, sending shutdown command..."
+
+  echo && info "Received $sig signal, sending shutdown command..."
 
   if ! readQemuPid pid; then
-    warn "QEMU PID file ($QEMU_PID) does not exist?"
-    finish "$code"
+    if ! interactive || ! waitQemuPid pid; then
+      warn "QEMU PID file does not exist?"
+      finish "$code"
+    fi
   fi
 
-  if ! isAlive "$pid"; then
+  if [ -z "$pid" ] || ! isAlive "$pid"; then
     warn "QEMU process with PID $pid does not exist?"
     finish "$code"
   fi
@@ -249,9 +387,21 @@ graceful_shutdown() {
   finish "$code"
 }
 
-! enabled "$SHUTDOWN" && return 0
+enableTrap() {
+
+  enabled "$SHUTDOWN" || return 0
+
+  # Keep Ctrl-C available to interactive users without installing an unnecessary
+  # SIGINT handler for background/container execution.
+  if interactive; then
+    _trap gracefulShutdown SIGINT
+  fi
+
+  _trap gracefulShutdown SIGTERM SIGHUP SIGABRT SIGQUIT
+
+  return 0
+}
+
 [ -n "${QEMU_TIMEOUT:-}" ] && TIMEOUT="$QEMU_TIMEOUT"
 
-_trap graceful_shutdown SIGTERM SIGHUP SIGABRT SIGQUIT
-
 return 0

src/print.sh

@@ -9,6 +9,7 @@ cd /run
 . utils.sh      # Load functions
 
 info () { printf "%b%s%b" "\E[1;34m❯ \E[1;36m" "$1" "\E[0m\n" >&2; }
+warn () { printf "%b%s%b" "\E[1;33m❯ " "WARNING: $1" "\E[0m\n" >&2; }
 error () { printf "%b%s%b" "\E[1;31m❯ " "ERROR: $1" "\E[0m\n" >&2; }
 
 disabled "$NETWORK" && exit 0
@@ -19,8 +20,9 @@ driver="/run/shm/qemu.nic"
 page="/run/shm/index.html"
 address="/run/shm/qemu.ip"
 shutdown="/run/shm/qemu.end"
+socket="/run/shm/qemu-host-api.sock"
 template="/var/www/index.html"
-url="http://127.0.0.1:2210/read?command=10"
+url="http://localhost/read?command=10"
 
 resp_err="Guest returned an invalid response:"
 curl_err="Failed to connect to guest: curl error"
@@ -35,9 +37,9 @@ exitIfShuttingDown() {
 
 queryGuest() {
 
-  local rc
-
-  { json=$(curl -m 20 -sk "$url"); rc=$?; } || :
+  # Query DSM through the qemu-host sidecar rather than the guest network,
+  # which may not be configured yet.
+  { json=$(curl --unix-socket "$socket" -m 20 -sk "$url"); local rc=$?; } || :
 
   exitIfShuttingDown
 
@@ -53,9 +55,8 @@ readJsonField() {
 
   local query="$1"
   local result
-  local rc
 
-  { result=$(jq -r "$query" <<< "$json"); rc=$?; } || :
+  { result=$(jq -r "$query" <<< "$json"); local rc=$?; } || :
 
   if (( rc != 0 )); then
     error "$jq_err $rc ( $json )"
@@ -73,12 +74,12 @@ readJsonField() {
 
 readGuestStatus() {
 
-  local result msg rc
+  local result msg
 
   result=$(readJsonField '.status') || return 1
 
   if [[ "$result" != "success" ]]; then
-    { msg=$(jq -r '.message // empty' <<< "$json"); rc=$?; } || :
+    { msg=$(jq -r '.message // empty' <<< "$json"); local rc=$?; } || :
 
     if (( rc != 0 )); then
       error "$jq_err $rc ( $json )"
@@ -117,6 +118,8 @@ writeDsmLocation() {
 
 pollGuestLocation() {
 
+  # Keep polling until the guest reports a usable address, but stop promptly
+  # when container shutdown begins.
   while [ ! -s "$file" ]; do
 
     # Check if not shutting down
@@ -139,14 +142,29 @@ pollGuestLocation() {
   return 0
 }
 
+checkAddressConflict() {
+
+  local guest_ip="${location%:*}"
+  local container_ip=""
+
+  [ -s "$address" ] && container_ip=$(<"$address")
+  [ -z "$container_ip" ] && return 0
+  [[ "$guest_ip" != "$container_ip" ]] && return 0
+
+  warn "DSM is using the same IP as the container, this will cause connectivity issues."
+  warn "change the container's macvlan IP or assign DSM a different address in your router."
+
+  return 0
+}
+
 writeDhcpPage() {
 
-  local title body script html
+  local html
 
   msg="http://$location"
-  title="<title>Virtual DSM</title>"
-  body="The location of DSM is <a href='http://$location'>http://$location</a>"
-  script="<script>setTimeout(function(){ window.location.assign('http://$location'); }, 3000);</script>"
+  local title="<title>Virtual DSM</title>"
+  local body="The location of DSM is <a href='http://$location'>http://$location</a>"
+  local script="<script>setTimeout(function(){ window.location.assign('http://$location'); }, 3000);</script>"
 
   html=$(<"$template")
   html="${html/\[1\]/$title}"
@@ -163,12 +181,14 @@ writeDhcpPage() {
 
 buildStaticMessage() {
 
-  local nic ip port
+  local nic ip
 
   nic=$(<"$driver")
   ip=$(<"$address")
-  port="${location##*:}"
+  local port="${location##*:}"
 
+  # NAT and user-mode networking are reached through a forwarded host port;
+  # macvlan exposes DSM directly on the container-facing LAN address.
   if [[ "${nic,,}" != "macvlan" ]]; then
     msg="port $port"
   else
@@ -195,6 +215,7 @@ exitIfShuttingDown
 location=$(<"$file")
 
 if enabled "$DHCP"; then
+  checkAddressConflict
   writeDhcpPage
 else
   buildStaticMessage

src/proc.sh

@@ -45,9 +45,9 @@ checkClocksource() {
 
 checkSse42() {
 
-  if ! grep -qw "sse4_2" <<< "$flags"; then
+  if ! hasFlag "sse4_2"; then
     error "Your CPU does not have the SSE4 instruction set that Virtual DSM requires!"
-    ! enabled "$DEBUG" && exit 88
+    enabled "$DEBUG" || exit 88
   fi
 
   return 0
@@ -66,6 +66,8 @@ trimSpaces() {
 
 removeCpuArgument() {
 
+  # CPU configuration has dedicated variables. Remove raw -cpu arguments so
+  # option ordering cannot silently override the validated model and flags.
   local args=" ${ARGUMENTS:-} "
 
   while [[ "$args" =~ [[:space:]]-cpu([[:space:]][^[:space:]]+|=[^[:space:]]+)? ]]; do
@@ -94,10 +96,12 @@ configureKvmCpuModel() {
 
 appendKvmInvtscFeature() {
 
-  if grep -qw "svm" <<< "$flags"; then
+  # invtsc is safe only when the active accelerator can scale the host TSC;
+  # AMD and Intel expose that capability through different host flags.
+  if hasFlag "svm"; then
 
     # AMD processor
-    if grep -qw "tsc_scale" <<< "$flags"; then
+    if hasFlag "tsc_scale"; then
       CPU_FEATURES+=",+invtsc"
     fi
 
@@ -131,6 +135,8 @@ configureTcgCpuModel() {
     return 0
   fi
 
+  # TCG uses the broad max model on native x86, but qemu64 is the compatible
+  # cross-architecture fallback.
   if [[ "$ARCH" == "amd64" ]]; then
     CPU_MODEL="max"
     CPU_FEATURES+=",migratable=no"
@@ -158,6 +164,8 @@ configureTcg() {
 
 composeCpuFlags() {
 
+  # Compose one -cpu value in precedence order: model, required features,
+  # then user-provided overrides.
   CPU_FLAGS="${CPU_MODEL}${CPU_FEATURES:+,$CPU_FEATURES}${CPU_FLAGS:+,$CPU_FLAGS}"
 
   return 0
@@ -170,6 +178,8 @@ configureHostCpuName() {
   fi
 
   if [ -n "$HOST_CPU" ]; then
+    # qemu-host expects a comma-separated CPU description with empty family
+    # and suffix fields, not QEMU's -cpu syntax.
     HOST_CPU="${HOST_CPU%%,*},,"
   else
     HOST_CPU="QEMU, Virtual CPU,"
@@ -186,8 +196,6 @@ configureHostCpuName() {
 selectClocksource
 checkClocksource
 
-flags=$(sed -ne '/^flags/s/^.*: //p' /proc/cpuinfo)
-
 if ! disabled "$KVM"; then
   configureKvm
 else

src/progress.sh

@@ -2,44 +2,309 @@
 set -Eeuo pipefail
 
 info="/run/shm/msg.html"
+info_tmp="${info}.${BASHPID}.tmp"
 
-escape () {
-    local s
-    s=${1//&/\&}
-    s=${s//</\&lt;}
-    s=${s//>/\&gt;}
-    s=${s//'"'/\&quot;}
-    printf -- %s "$s"
+escape() {
+
+  local s
+
+  s=${1//&/\&amp;}
+  s=${s//</\&lt;}
+  s=${s//>/\&gt;}
+  s=${s//'"'/\&quot;}
+  s=${s//"'"/\&#39;}
+
+  printf '%s' "$s"
+  return 0
+}
+
+writeInfo() {
+
+  local content="$1"
+
+  # Replace the web status atomically so websocket readers never observe a
+  # partially written HTML fragment.
+  if ! printf '%s\n' "$content" > "$info_tmp"; then
+    rm -f -- "$info_tmp"
+    return 1
+  fi
+
+  if ! mv -f -- "$info_tmp" "$info"; then
+    rm -f -- "$info_tmp"
+    return 1
+  fi
+
+  return 0
+}
+
+getBytes() {
+
+  local path="$1"
+  local mode="$2"
+  local bytes="0"
+
+  if [[ "$mode" == "counter" ]]; then
+    if [ -r "$path" ]; then
+      read -r bytes < "$path" || bytes="0"
+    fi
+
+    [[ "$bytes" =~ ^[0-9]+$ ]] || bytes="0"
+    printf '%s\n' "$bytes"
     return 0
+  fi
+
+  if [ ! -s "$path" ] && [ ! -d "$path" ]; then
+    printf '0\n'
+    return 0
+  fi
+
+  if [[ "$mode" == "allocated" ]]; then
+    bytes=$(du -sB1 -- "$path" 2>/dev/null | cut -f1) || bytes="0"
+  else
+    bytes=$(du -sb -- "$path" 2>/dev/null | cut -f1) || bytes="0"
+  fi
+
+  printf '%s\n' "$bytes"
+  return 0
+}
+
+getStatus() {
+
+  local file="$1"
+  local bytes total extra=""
+
+  [ -r "$file" ] || return 1
+  read -r bytes total extra < "$file" || return 1
+
+  if [[ ! "$bytes" =~ ^[0-9]+$ ||
+        ! "$total" =~ ^[0-9]+$ ||
+        -n "$extra" ]]; then
+    return 1
+  fi
+
+  printf '%s %s\n' "$bytes" "$total"
+  return 0
+}
+
+formatSize() {
+
+  local bytes="$1"
+  local size
+
+  size=$(numfmt --to=iec --suffix=B "$bytes" |
+    sed -r 's/([A-Z])/ \1/') ||
+    size="${bytes} bytes"
+
+  printf '%s' "$size"
+  return 0
+}
+
+printPercentProgress() {
+
+  local percent="$1"
+
+  while (( next_percent <= percent && next_percent <= 100 )); do
+    if [[ "$printed" == "Y" ]]; then
+      printf ' → %s%%' "$next_percent"
+    else
+      printf '%s%%' "$next_percent"
+    fi
+
+    printed="Y"
+    next_percent=$((next_percent + 10))
+  done
+
+  return 0
+}
+
+printCurrentSize() {
+
+  local bytes="$1"
+  local size
+
+  size=$(formatSize "$bytes")
+
+  if [[ "$printed" == "Y" ]]; then
+    printf ' → %s' "$size"
+  else
+    printf '%s' "$size"
+  fi
+
+  printed="Y"
+  return 0
+}
+
+printSizeProgress() {
+
+  local bytes="$1"
+  local size
+
+  while (( bytes >= next_bytes )); do
+    size=$(formatSize "$next_bytes")
+
+    if [[ "$printed" == "Y" ]]; then
+      printf ' → %s' "$size"
+    else
+      printf '%s' "$size"
+    fi
+
+    printed="Y"
+    next_bytes=$((next_bytes + step_bytes))
+  done
+
+  return 0
+}
+
+stopProgress() {
+
+  if [ -z "$status_file" ]; then
+    exit 0
+  fi
+
+  stopping="Y"
+  return 0
+}
+
+finishProgress() {
+
+  rm -f -- "$info_tmp"
+
+  if [[ "$output" == "log" && "$printed" == "Y" ]]; then
+    printf '\n'
+  fi
+
+  return 0
 }
 
 path="$1"
 total="$2"
 body=$(escape "$3")
+output="${4:-}"
+step_bytes="${5:-536870912}"
+mode="${6:-apparent}"
+status_file="${7:-}"
+
+if [[ -n "$total" && ! "$total" =~ ^(0|[1-9][0-9]*)$ ]]; then
+  printf 'Invalid total size: %s\n' "$total" >&2
+  exit 2
+fi
+
+if [[ ! "$step_bytes" =~ ^[1-9][0-9]*$ ]]; then
+  printf 'Invalid progress interval: %s\n' "$step_bytes" >&2
+  exit 2
+fi
+
+case "$mode" in
+  apparent | allocated | counter ) ;;
+  * )
+    printf 'Invalid progress mode: %s\n' "$mode" >&2
+    exit 2
+    ;;
+esac
+
+case "$output" in
+  "" | log ) ;;
+  * )
+    printf 'Invalid progress output: %s\n' "$output" >&2
+    exit 2
+    ;;
+esac
+
+printed="N"
+next_percent=10
+next_bytes="$step_bytes"
+log_mode="percent"
+stopping="N"
+
+if [ -z "$total" ] || [[ "$total" == "0" ]]; then
+  log_mode="size"
+fi
+
+trap finishProgress EXIT
+trap 'exit 0' HUP INT QUIT
+# SIGTERM requests one final measurement and web update rather than
+# terminating between progress samples.
+trap stopProgress TERM
 
 if [[ "$body" == *"..." ]]; then
   body="<p class=\"loading\">${body::-3}</p>"
 fi
 
-while true
-do
+while true; do
 
-  if [ ! -s "$path" ] && [ ! -d "$path" ]; then
-    bytes="0"
-  else
-    bytes=$(du -sb "$path" 2>/dev/null | cut -f1) || bytes="0"
-  fi
-  
-  if (( bytes > 4096 )); then
-    if [ -z "$total" ] || [[ "$total" == "0" ]] || [ "$bytes" -gt "$total" ]; then
-      size=$(numfmt --to=iec --suffix=B "$bytes" | sed -r 's/([A-Z])/ \1/') || size="${bytes} bytes"
-    else
-      size="$(echo "$bytes" "$total" | awk '{printf "%.1f", $1 * 100 / $2}')"
-      size="$size%"
+  final_pass="${stopping:-}"
+  bytes=$(getBytes "$path" "$mode")
+  effective_total="$total"
+
+  # An external downloader may provide authoritative completed and total byte
+  # counters; use them instead of filesystem size when available.
+  if [ -n "$status_file" ] && status=$(getStatus "$status_file"); then
+    read -r status_bytes status_total <<< "$status"
+    bytes="$status_bytes"
+
+    if (( status_total > 0 )); then
+      effective_total="$status_total"
     fi
-    [[ "$size" != "0.0%" ]] && echo "${body//(\[P\])/($size)}"> "$info"
   fi
 
-  sleep 1 & wait $!
+  # A real total may become available shortly after aria2 starts.
+  if [[ "$log_mode" == "size" &&
+        "$printed" == "N" &&
+        -n "$effective_total" &&
+        "$effective_total" != "0" ]]; then
+    log_mode="percent"
+  fi
 
+  if (( bytes > 4096 )); then
+
+    write_html="Y"
+
+    if [ -z "$effective_total" ] ||
+        [[ "$effective_total" == "0" ]] ||
+        (( bytes > effective_total )); then
+      size=$(formatSize "$bytes")
+
+      if [[ "$output" == "log" ]]; then
+        if [[ "$log_mode" == "percent" ]]; then
+          printCurrentSize "$bytes"
+          next_bytes=$(((bytes / step_bytes + 1) * step_bytes))
+          log_mode="size"
+        else
+          printSizeProgress "$bytes"
+        fi
+      fi
+    else
+      # Floor the percentage rather than rounding so displayed completion
+      # never gets ahead of bytes actually written.
+      # Truncate to one decimal so progress is never reported early.
+      progress=$((bytes * 1000 / effective_total))
+      (( progress > 1000 )) && progress=1000
+
+      percent=$((progress / 10))
+
+      printf -v size '%d.%d%%' \
+        "$((progress / 10))" \
+        "$((progress % 10))"
+
+      if [[ "$output" == "log" ]]; then
+        if [[ "$log_mode" == "size" ]]; then
+          printSizeProgress "$bytes"
+        else
+          printPercentProgress "$percent"
+        fi
+      fi
+
+      # Do not update the web viewer until at least 0.1% is reached.
+      (( progress == 0 )) && write_html="N"
+    fi
+
+    if [[ "$write_html" == "Y" ]]; then
+      writeInfo "${body//(\[P\])/($size)}"
+    fi
+  fi
+
+  [[ "$final_pass" == "Y" ]] && break
+
+  sleep 1 &
+  wait $! || :
 done

src/serial.sh

@@ -15,6 +15,10 @@ HOST_MODEL=$(strip "$HOST_MODEL")
 HOST_SERIAL=$(strip "$HOST_SERIAL")
 GUEST_SERIAL=$(strip "$GUEST_SERIAL")
 
+HOST_PID="$QEMU_DIR/host.pid"
+HOST_API_SOCKET="$QEMU_DIR/qemu-host-api.sock"
+HOST_AGENT_SOCKET="$QEMU_DIR/qemu-host-agent.sock"
+
 validateHostMac() {
   local m
 
@@ -38,9 +42,13 @@ validateHostMac() {
 
 buildHostArguments() {
 
+  # qemu-host is a sidecar that bridges DSM's proprietary serial agent to
+  # Unix sockets used by shutdown and post-boot discovery helpers.
   HOST_ARGS=()
   HOST_ARGS+=("-cpu=$CPU_CORES")
   HOST_ARGS+=("-cpu_arch=$HOST_CPU")
+  HOST_ARGS+=("-api=$HOST_API_SOCKET")
+  HOST_ARGS+=("-addr=$HOST_AGENT_SOCKET")
 
   [ -n "$HOST_MAC" ] && HOST_ARGS+=("-mac=$HOST_MAC")
   [ -n "$HOST_MODEL" ] && HOST_ARGS+=("-model=$HOST_MODEL")
@@ -52,30 +60,50 @@ buildHostArguments() {
 
 startHostBinary() {
 
+  local pid
+
+  # Remove stale sockets and pid state before starting the sidecar; a Unix
+  # socket path cannot be rebound while an old filesystem entry remains.
+  rm -f -- "$HOST_PID" "$HOST_API_SOCKET" "$HOST_AGENT_SOCKET" || return 1
+
   if enabled "$HOST_DEBUG"; then
     set -x
     ./host.bin "${HOST_ARGS[@]}" &
     { set +x; } 2>/dev/null
-    echo "$!" > "$HOST_PID"
+    pid=$!
     echo
   else
     ./host.bin "${HOST_ARGS[@]}" >/dev/null &
-    echo "$!" > "$HOST_PID"
+    pid=$!
   fi
 
+  printf '%s\n' "$pid" > "$HOST_PID"
+
   return 0
 }
 
-waitForPort() {
+waitForSocket() {
 
-  local port="$1"
+  local socket="$1"
   local exit_code="$2"
-  local cnt=0
+  local timeout=5 pid
+  local deadline=$((SECONDS + timeout))
+
+  # Do not start QEMU until both sidecar sockets are ready; otherwise the
+  # VirtIO serial channel or API client may race initial creation.
+  while [ ! -S "$socket" ]; do
+
+    if ! readPidFile pid "$HOST_PID" || ! isAlive "$pid"; then
+      error "qemu-host exited unexpectedly!"
+      exit "$exit_code"
+    fi
+
+    if (( SECONDS >= deadline )); then
+      error "Failed to create qemu-host socket: $socket"
+      exit "$exit_code"
+    fi
 
-  while ! nc -z -w2 127.0.0.1 "$port" > /dev/null 2>&1; do
     sleep 0.1
-    cnt=$((cnt + 1))
-    (( cnt > 50 )) && error "Failed to connect to qemu-host.." && exit "$exit_code"
   done
 
   return 0
@@ -83,10 +111,30 @@ waitForPort() {
 
 configureSerialPorts() {
 
-  # Configure serial ports
-  SERIAL_OPTS="-serial mon:stdio \
-        -device virtio-serial-pci,id=virtio-serial0,bus=pcie.0,addr=0x3 \
-        -chardev socket,id=charchannel0,host=127.0.0.1,port=$CHR_PORT,reconnect=10 \
+  local bus
+  bus=$(getPciBus)
+
+  # Managed interactive mode separates the console and QEMU monitor into
+  # reconnecting sockets; other runs keep the simple combined stdio monitor.
+  if enabled "${SHUTDOWN:-Y}" && interactive; then
+
+    CONSOLE_SOCKET="$QEMU_DIR/console.sock"
+    MONITOR_SOCKET="$QEMU_DIR/monitor.sock"
+
+    SERIAL_OPTS="-chardev socket,id=console0,path=$CONSOLE_SOCKET,reconnect-ms=1000 \
+          -serial chardev:console0 \
+          -chardev socket,id=monitor0,path=$MONITOR_SOCKET,server=on,wait=off \
+          -mon chardev=monitor0,mode=readline"
+
+  else
+
+    SERIAL_OPTS="-serial mon:stdio"
+
+  fi
+
+  SERIAL_OPTS+=" \
+        -device virtio-serial-pci,id=virtio-serial0,bus=$bus,addr=0x3 \
+        -chardev socket,id=charchannel0,path=$HOST_AGENT_SOCKET,reconnect-ms=1000 \
         -device virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=vchannel"
 
   return 0
@@ -94,15 +142,11 @@ configureSerialPorts() {
 
 validateHostMac
 
-HOST_PID="$QEMU_DIR/host.pid"
-
 buildHostArguments
 startHostBinary
 
-sleep 0.2
-
-waitForPort "$COM_PORT" 58
-waitForPort "$CHR_PORT" 59
+waitForSocket "$HOST_API_SOCKET" 58
+waitForSocket "$HOST_AGENT_SOCKET" 59
 
 configureSerialPorts
 

src/server.sh

@@ -1,41 +1,72 @@
 #!/usr/bin/env bash
 set -Eeuo pipefail
 
-: "${COM_PORT:="2210"}"    # Comm port
 : "${WEB_PORT:="5000"}"    # Webserver port
-: "${CHR_PORT:="12345"}"   # Character port
-: "${WSD_PORT:="8004"}"    # Websockets port
 
 # Sanitize port variables
-COM_PORT=$(strip "$COM_PORT")
 WEB_PORT=$(strip "$WEB_PORT")
-CHR_PORT=$(strip "$CHR_PORT")
-WSD_PORT=$(strip "$WSD_PORT")
 
 WEB_PID="/run/nginx.pid"
+WSD_LOG="/var/log/websocketd.log"
 WSD_PID="$QEMU_DIR/websocketd.pid"
+WSD_SOCKET="$QEMU_DIR/status-ws.sock"
 
 prepareWebFiles() {
 
   cp -r /var/www/* "$QEMU_DIR" || return 1
-  rm -f "$WSD_PID" "$WEB_PID" || return 1
+  rm -f -- "$WSD_PID" "$WSD_SOCKET" "$WEB_PID" "$WSD_LOG" || return 1
 
   return 0
 }
 
 configureWebPorts() {
 
-  sed -i "s/listen 5000 default_server;/listen $WEB_PORT default_server;/g" /etc/nginx/sites-enabled/web.conf
-  sed -i "s/proxy_pass http:\/\/127.0.0.1:8004\/;/proxy_pass http:\/\/127.0.0.1:$WSD_PORT\/;/g" /etc/nginx/sites-enabled/web.conf
+  if ! sed -i \
+    -e "s|listen 5000 default_server;|listen $WEB_PORT default_server;|g" \
+    /etc/nginx/sites-enabled/web.conf; then
+    error "Failed to configure webserver port!"
+    return 1
+  fi
 
   return 0
 }
 
 configureIpv6Listen() {
 
-  # shellcheck disable=SC2143
+  # Use one dual-stack listener when IPv6 is active, avoiding separate IPv4
+  # and IPv6 sockets that can conflict on the same port.
   if [ -f /proc/net/if_inet6 ] && [[ "$(cat /proc/sys/net/ipv6/conf/all/disable_ipv6 2>/dev/null)" != "1" ]]; then
-    sed -i "s/listen $WEB_PORT default_server;/listen [::]:$WEB_PORT default_server ipv6only=off;/g" /etc/nginx/sites-enabled/web.conf
+
+    if ! sed -i \
+      "s/listen $WEB_PORT default_server;/listen [::]:$WEB_PORT default_server ipv6only=off;/g" \
+      /etc/nginx/sites-enabled/web.conf; then
+      error "Failed to configure IPv6 webserver listener!"
+      return 1
+    fi
+
+  fi
+
+  return 0
+}
+
+configureNginx() {
+
+  mkdir -p /etc/nginx/sites-enabled || return 1
+  rm -f /etc/nginx/sites-enabled/default || return 1
+
+  # TODO: Use setfacl to grant www-data access to the Unix sockets
+  # and restore unprivileged nginx workers.
+  if ! sed -i \
+    -e 's/^user .*/user root;/' \
+    -e 's/^worker_processes.*/worker_processes 1;/' \
+    /etc/nginx/nginx.conf; then
+    error "Failed to configure nginx!"
+    return 1
+  fi
+
+  if ! cp /etc/nginx/default.conf /etc/nginx/sites-enabled/web.conf; then
+    error "Failed to copy nginx config!"
+    return 1
   fi
 
   return 0
@@ -43,15 +74,31 @@ configureIpv6Listen() {
 
 configureWebServer() {
 
-  mkdir -p /etc/nginx/sites-enabled
-  cp /etc/nginx/default.conf /etc/nginx/sites-enabled/web.conf
-
+  configureNginx || return 1
   configureWebPorts || return 1
   configureIpv6Listen || return 1
 
   return 0
 }
 
+stopWebServer() {
+
+  local pid
+
+  if readPidFile pid "$WEB_PID"; then
+    pKill "$pid" 2
+
+    # Escalate only after the normal termination grace period; stale nginx
+    # processes would otherwise keep the configured web port occupied.
+    if isAlive "$pid"; then
+      kill -9 -- "$pid" 2>/dev/null || :
+    fi
+  fi
+
+  rm -f -- "$WEB_PID"
+  return 0
+}
+
 startWebServer() {
 
   # Start webserver
@@ -60,41 +107,79 @@ startWebServer() {
   return 0
 }
 
+stopWebsocketServer() {
+
+  local pid
+
+  if readPidFile pid "$WSD_PID"; then
+    pKill "$pid" 2
+
+    if isAlive "$pid"; then
+      kill -9 -- "$pid" 2>/dev/null || :
+    fi
+  fi
+
+  rm -f -- "$WSD_PID" "$WSD_SOCKET"
+  return 0
+}
+
 startWebsocketServer() {
 
-  local log="/var/log/websocketd.log"
-  rm -f "$log"
-
   # Start websocket server
-  websocketd --address 127.0.0.1 --port="$WSD_PORT" /run/socket.sh > "$log" 2>&1 &
+  websocketd \
+    --unixsocket="$WSD_SOCKET" \
+    /run/socket.sh \
+    >"$WSD_LOG" 2>&1 &
+
   local pid=$!
 
   if ! echo "$pid" > "$WSD_PID"; then
     kill "$pid" 2>/dev/null || :
+    rm -f -- "$WSD_PID"
     return 1
   fi
 
-  sleep 0.1
+  local i
+  for (( i = 1; i <= 50; i++ )); do
 
-  if ! isAlive "$pid"; then
-    rm -f "$WSD_PID"
-    [ -s "$log" ] && cat "$log" >&2
-    error "Failed to start websocket server!"
-    return 1
+    if ! isAlive "$pid"; then
+      rm -f -- "$WSD_PID" "$WSD_SOCKET"
+      [ -s "$WSD_LOG" ] && cat "$WSD_LOG" >&2
+      error "Failed to start websocket server!"
+      return 1
+    fi
+
+    [ -S "$WSD_SOCKET" ] && return 0
+
+    sleep 0.1
+
+  done
+
+  pKill "$pid" 2
+
+  if isAlive "$pid"; then
+    kill -9 -- "$pid" 2>/dev/null || :
   fi
 
-  return 0
+  rm -f -- "$WSD_PID" "$WSD_SOCKET"
+  [ -s "$WSD_LOG" ] && cat "$WSD_LOG" >&2
+  error "Websocket server did not create its socket!"
+  return 1
 }
 
-prepareWebFiles || return 1
+prepareWebFiles
 
 html "Starting $APP for $ENGINE..."
 
 disabled "${WEB:-}" && return 0
 
-configureWebServer || return 1
+configureWebServer
 
-startWebServer || return 1
-startWebsocketServer || return 1
+if startWebServer && startWebsocketServer; then
+  return 0
+fi
 
-return 0
+stopWebsocketServer || :
+stopWebServer || :
+
+return 1

src/socket.sh

@@ -3,6 +3,8 @@ set -Eeuo pipefail
 
 lastmsg=""
 path="/run/shm/msg.html"
+dir=$(dirname -- "$path")
+name=$(basename -- "$path")
 
 refresh() {
 
@@ -16,16 +18,31 @@ refresh() {
   [[ "$msg" == "$lastmsg" ]] && return 0
 
   lastmsg="$msg"
+  # websocketd clients interpret s: as a status update and c: as a command;
+  # suppress unchanged status to avoid redundant browser work.
   echo "s: $msg"
+
   return 0
 }
 
 refresh
 
-inotifywait -m "$path" |
-  while read -r fp event fn; do
+inotifywait \
+  -m -q \
+  -e close_write,moved_to,delete \
+  --format '%e %f' \
+  "$dir" |
+  while read -r event file; do
+
+    [[ "$file" == "$name" ]] || continue
+
     case "${event,,}" in
-      "modify"* ) refresh ;;
-      "delete_self" ) echo "c: vnc" ;;
-    esac    
+      "delete"* )
+        echo "c: vnc" ;;
+      # moved_to covers the atomic replacement used by html()/writeAtomic(),
+      # while close_write handles direct writers.
+      "close_write"* | "moved_to"* )
+        refresh ;;
+    esac
+
   done

src/utils.sh

@@ -7,6 +7,79 @@ info () { printf "%b%s%b" "\E[1;34m❯ \E[1;36m" "${1:-}" "\E[0m\n"; }
 error () { printf "%b%s%b" "\E[1;31m❯ " "ERROR: ${1:-}" "\E[0m\n" >&2; }
 warn () { printf "%b%s%b" "\E[1;31m❯ " "Warning: ${1:-}" "\E[0m\n" >&2; }
 
+app() {
+
+  echo "Virtual DSM"
+  return 0
+}
+
+readPidFile() {
+
+  local -n _pid="$1"
+  _pid=""
+
+  if ! _pid=$(cat -- "$2" 2>/dev/null); then
+    _pid=""
+    return 1
+  fi
+
+  # Reject empty, zero, or nonnumeric pidfiles so cleanup can never signal an
+  # unintended process group.
+  if [[ ! "$_pid" =~ ^[1-9][0-9]*$ ]]; then
+    _pid=""
+    return 1
+  fi
+
+  return 0
+}
+
+hasFlag() {
+
+  # Match a whitespace-delimited token in /proc/cpuinfo
+  grep -m1 '^flags[[:space:]]*:' /proc/cpuinfo | grep -Fqw -- "$1"
+
+}
+
+hasFeature() {
+
+  # Match a whitespace-delimited token in /proc/cpuinfo
+  grep -m1 '^Features[[:space:]]*:' /proc/cpuinfo | grep -Fqw -- "$1"
+
+}
+
+isAmdCpu() {
+
+  local vendor
+  vendor=$(awk -F ': *' '/^vendor_id/{print $2; exit}' /proc/cpuinfo)
+
+  [[ "$vendor" == "AuthenticAMD" ]]
+}
+
+getPciBus() {
+
+  local machine="${1:-${MACHINE:-q35}}"
+
+  if [ -n "${PCI_BUS:-}" ]; then
+    echo "$PCI_BUS"
+    return 0
+  fi
+
+  case "${machine,,}" in
+    pc|pc-i440fx*) echo "pci.0" ;;
+    *)             echo "pcie.0" ;;
+  esac
+
+  return 0
+}
+
+interactive() {
+
+  # A TTY on stdin is insufficient when /dev/tty is unavailable; require both
+  # before enabling interactive console handling.
+  [ -t 0 ] && : 2>/dev/null </dev/tty >/dev/tty
+
+}
+
 strip() {
 
   local value="${1:-}"
@@ -90,14 +163,13 @@ isAlive() {
 
 waitPid() {
 
-  local i=0
   local pid="$1"
   local timeout="${2:-10}"
+  local deadline=$((SECONDS + timeout))
 
   while [ -n "$pid" ] && isAlive "$pid"; do
+    (( SECONDS >= deadline )) && return 1
     sleep 0.2
-    i=$((i + 1))
-    (( i >= timeout * 5 )) && return 1
   done
 
   return 0
@@ -105,19 +177,16 @@ waitPid() {
 
 waitPidFile() {
 
-  local i=0
-  local pid=""
+  local pid
   local file="$1"
   local timeout="${2:-10}"
+  local deadline=$((SECONDS + timeout))
 
-  [ ! -s "$file" ] && return 0
-  ! read -r pid <"$file" && return 0
-  [ -z "$pid" ] && return 0
+  readPidFile pid "$file" || return 0
 
   while [ -s "$file" ] && isAlive "$pid"; do
+    (( SECONDS >= deadline )) && return 1
     sleep 0.2
-    i=$((i + 1))
-    (( i >= timeout * 5 )) && return 1
   done
 
   rm -f -- "$file"
@@ -140,19 +209,19 @@ pKill() {
 
 fWait() {
 
-  local i=0
   local name="$1"
   local timeout="${2:-10}"
+  local deadline=$((SECONDS + timeout))
 
   [ -z "$name" ] && return 0
 
   while pgrep -f -l "$name" >/dev/null; do
-    sleep 0.2
-    i=$((i + 1))
-    if (( i >= timeout * 5 )); then
+    if (( SECONDS >= deadline )); then
       warn "Timed out while waiting for process: $name"
       break
     fi
+
+    sleep 0.2
   done
 
   return 0
@@ -173,12 +242,10 @@ fKill() {
 
 sKill() {
 
-  local pid=""
+  local pid
   local file="$1"
 
-  [ ! -s "$file" ] && return 0
-  ! read -r pid <"$file" && return 0
-  [ -z "$pid" ] && return 0
+  readPidFile pid "$file" || return 0
 
   if isAlive "$pid"; then
     { kill -15 -- "$pid" || :; } 2>/dev/null
@@ -212,11 +279,13 @@ setOwner() {
 
   [ ! -f "$file" ] && return 1
 
+  # Match generated files to the owner of their bind-mounted parent directory
+  # instead of assuming a fixed container or host UID.
   dir=$(dirname -- "$file")
   uid=$(stat -c '%u' "$dir") || return 1
   gid=$(stat -c '%g' "$dir") || return 1
 
-  ! chown "$uid:$gid" "$file" && return 1
+  chown "$uid:$gid" "$file" || return 1
 
   return 0
 }
@@ -227,7 +296,7 @@ makeDir() {
   local dir uid gid
 
   [ -d "$path" ] && return 0
-  ! mkdir -p "$path" && return 1
+  mkdir -p "$path" || return 1
 
   dir=$(dirname -- "$path")
 
@@ -244,6 +313,64 @@ makeDir() {
   return 0
 }
 
+finiteMemoryLimit() {
+
+  local limit="$1"
+  # cgroup v1 commonly reports this enormous sentinel for an unlimited memory
+  # limit; compare as decimal strings to avoid shell integer overflow.
+  local sentinel="4611686018427387904"
+  local i
+
+  [[ "$limit" =~ ^[0-9]+$ ]] || return 1
+
+  (( ${#limit} < ${#sentinel} )) && return 0
+  (( ${#limit} > ${#sentinel} )) && return 1
+
+  for (( i=0; i<${#sentinel}; i++ )); do
+    local left="${limit:i:1}"
+    local right="${sentinel:i:1}"
+
+    (( left < right )) && return 0
+    (( left > right )) && return 1
+  done
+
+  return 1
+}
+
+getMemoryInfo() {
+
+  local host_total
+  local host_avail
+  local limit=""
+  local current=""
+
+  host_total=$(free -b | awk '/^Mem:/ {print $2; exit}')
+  host_avail=$(free -b | awk '/^Mem:/ {print $7; exit}')
+
+  RAM_TOTAL="$host_total"
+  RAM_AVAIL="$host_avail"
+
+  if [ -r /sys/fs/cgroup/memory.max ] && [ -r /sys/fs/cgroup/memory.current ]; then
+    limit=$(< /sys/fs/cgroup/memory.max)
+    current=$(< /sys/fs/cgroup/memory.current)
+  elif [ -r /sys/fs/cgroup/memory/memory.limit_in_bytes ] && [ -r /sys/fs/cgroup/memory/memory.usage_in_bytes ]; then
+    limit=$(< /sys/fs/cgroup/memory/memory.limit_in_bytes)
+    current=$(< /sys/fs/cgroup/memory/memory.usage_in_bytes)
+  fi
+
+  # Use the tighter of host availability and the container's remaining cgroup
+  # allowance so RAM sizing cannot exceed either boundary.
+  if finiteMemoryLimit "$limit" && [[ "$current" =~ ^[0-9]+$ ]]; then
+    (( limit < RAM_TOTAL )) && RAM_TOTAL="$limit"
+
+    local available=$(( limit - current ))
+    (( available < 0 )) && available=0
+    (( available < RAM_AVAIL )) && RAM_AVAIL="$available"
+  fi
+
+  return 0
+}
+
 stateFile() {
 
   local name="$1"
@@ -272,6 +399,27 @@ writeFile() {
   return 0
 }
 
+writeAtomic() {
+
+  local path="$1"
+  local content="$2"
+  # Use a per-process temporary file and rename so readers see either the old
+  # complete value or the new complete value.
+  local tmp="${path}.${BASHPID}.tmp"
+
+  if ! printf '%s\n' "$content" > "$tmp"; then
+    rm -f -- "$tmp"
+    return 1
+  fi
+
+  if ! mv -f -- "$tmp" "$path"; then
+    rm -f -- "$tmp"
+    return 1
+  fi
+
+  return 0
+}
+
 readFile() {
 
   local path="$1"
@@ -321,6 +469,8 @@ restoreState() {
   local prefix="${4:-$PROCESS}"
   local value
 
+  # Persistent state fills only unset variables unless force is requested,
+  # preserving explicit environment overrides.
   if ! enabled "$force"; then
     [ -z "${!var:-}" ] || return 0
   fi
@@ -334,8 +484,7 @@ restoreState() {
 
 escape () {
 
-  local s
-  s=${1//&/\&amp;}
+  local s=${1//&/\&amp;}
   s=${s//</\&lt;}
   s=${s//>/\&gt;}
   s=${s//'"'/\&quot;}
@@ -345,11 +494,23 @@ escape () {
   return 0
 }
 
+escapeXML() {
+
+  printf '%s' "$1" | sed \
+    -e 's/&/\&amp;/g' \
+    -e 's/</\&lt;/g' \
+    -e 's/>/\&gt;/g' \
+    -e 's/"/\&quot;/g' \
+    -e "s/'/\&apos;/g"
+
+  return 0
+}
+
 html() {
 
   local title
   local body
-  local script
+  local script="${2:-}"
   local footer
 
   title=$(escape "$APP")
@@ -361,8 +522,6 @@ html() {
     body="<p class=\"loading\">${body/.../}</p>"
   fi
 
-  [ -n "${2:-}" ] && script="$2" || script=""
-
   local HTML
   HTML=$(<"$TEMPLATE")
   HTML="${HTML/\[1\]/$title}"
@@ -371,8 +530,10 @@ html() {
   HTML="${HTML/\[4\]/$footer}"
   HTML="${HTML/\[5\]/$FOOTER2}"
 
-  echo "$HTML" > "$PAGE" || return 1
-  echo "$body" > "$INFO" || return 1
+  # Publish both the full page and websocket fragment atomically because nginx
+  # and websocketd may read them concurrently.
+  writeAtomic "$PAGE" "$HTML" || return 1
+  writeAtomic "$INFO" "$body" || return 1
 
   return 0
 }
@@ -415,29 +576,13 @@ cpu() {
   return 0
 }
 
-hasDisk() {
-
-  enabled "${DISK_DISABLE:-}" && return 1
-
-  [ -b "/disk" ] && return 0
-  [ -b "/disk1" ] && return 0
-  [ -b "/dev/disk1" ] && return 0
-  [ -b "${DEVICE:-}" ] && return 0
-
-  [ -z "${DISK_NAME:-}" ] && DISK_NAME="data"
-  [ -s "$STORAGE/$DISK_NAME.img" ]  && return 0
-  [ -s "$STORAGE/$DISK_NAME.qcow2" ] && return 0
-
-  return 1
-}
-
 getCountry() {
 
   local url=$1
   local query=$2
-  local rc json result
+  local json result
 
-  { json=$(curl -m 5 -H "Accept: application/json" -sfk "$url"); rc=$?; } || :
+  { json=$(curl -m 5 -H "Accept: application/json" -sfk "$url"); local rc=$?; } || :
   (( rc != 0 )) && return 0
 
   { result=$(echo "$json" | jq -r "$query" 2> /dev/null); rc=$?; } || :
@@ -460,6 +605,8 @@ setCountry() {
   [[ "${TZ,,}" == "asia/shanghai" ]] && COUNTRY="CN"
   [[ "${TZ,,}" == "asia/chongqing" ]] && COUNTRY="CN"
 
+  # Country detection is best-effort and tries independent services in order;
+  # failure leaves mirror selection at its global default.
   [ -z "$COUNTRY" ] && getCountry "https://api.ipapi.is" ".location.country_code"
   [ -z "$COUNTRY" ] && getCountry "https://ifconfig.co/json" ".country_iso"
   [ -z "$COUNTRY" ] && getCountry "https://api.ip2location.io" ".country_code"
@@ -484,6 +631,8 @@ addPackage() {
 
   [ -z "$COUNTRY" ] && setCountry
 
+  # Use a mainland mirror only for on-demand package installation, avoiding
+  # slow or inaccessible Debian endpoints in that region.
   if [[ "${COUNTRY^^}" == "CN" ]]; then
     sed -i 's/deb.debian.org/mirrors.ustc.edu.cn/g' /etc/apt/sources.list.d/debian.sources
   fi

web/conf/nginx.conf

@@ -39,6 +39,6 @@ server {
       proxy_read_timeout 3600s;
       proxy_send_timeout 3600s;
 
-      proxy_pass http://127.0.0.1:8004/;
-    }    
+      proxy_pass http://unix:/run/shm/status-ws.sock:/;
+    }
 }

web/js/script.js

@@ -1,15 +1,27 @@
+var timer;
 var request;
 var booting = false;
 var interval = 1000;
 
+function abortRequest() {
+
+    if (!request) {
+        return false;
+    }
+
+    request.onreadystatechange = null;
+    request.abort();
+    request = null;
+
+    return true;
+}
+
 function getInfo() {
 
     var url = "msg.html";
 
     try {
-        if (request) {
-            request.abort();
-        }
+        abortRequest();
 
         if (window.XMLHttpRequest) {
             request = new XMLHttpRequest();
@@ -56,7 +68,17 @@ function processInfo() {
             return true;
         }
 
-        var msg = request.responseText;
+        var response = request;
+        request = null;
+
+        var status = response.status;
+
+        if (status == 502 || status == 503 || status == 504) {
+            schedule();
+            return true;
+        }
+
+        var msg = response.responseText;
         if (msg == null || msg.length == 0) {
 
             if (booting) {
@@ -68,9 +90,9 @@ function processInfo() {
             return false;
         }
 
-        var notFound = (request.status == 404);
+        var notFound = (status == 404);
 
-        if (request.status == 200) {
+        if (status == 200) {
             if (msg.toLowerCase().indexOf("<html>") !== -1) {
                 notFound = true;
             } else {
@@ -88,7 +110,7 @@ function processInfo() {
             return true;
         }
 
-        setError("Error: Received statuscode " + request.status);
+        setError("Error: Received statuscode " + status);
         return false;
 
     } catch (e) {
@@ -157,7 +179,9 @@ function setError(text) {
 }
 
 function schedule() {
-    setTimeout(getInfo, interval);
+
+    clearTimeout(timer);
+    timer = setTimeout(getInfo, interval);
 }
 
 function reload() {
@@ -179,11 +203,27 @@ function connect() {
 
         switch (cmd) {
             case "s":
+
+                var aborted = abortRequest();
+
                 processMsg(msg);
+
+                if (aborted &&
+                    msg.toLowerCase().indexOf("href=") == -1) {
+                    schedule();
+                }
+
                 break;
+
             case "e":
+
+                if (abortRequest()) {
+                    schedule();
+                }
+
                 setError(msg);
                 break;
+
             default:
                 console.warn("Unknown event: " + cmd);
                 break;