Add dockerfile and local management script for local development

Author: arr2036

Dockerfile

@@ -0,0 +1,22 @@
+FROM ubuntu:24.04
+ARG IMAGE_FINGERPRINT
+LABEL dev.fingerprint="${IMAGE_FINGERPRINT}"
+
+ENV DEBIAN_FRONTEND=noninteractive
+RUN apt-get update && apt-get install -y \
+    --no-install-recommends \
+    build-essential \
+    clang \
+    clang-tools \
+    cmake \
+    ninja-build \
+    pkg-config \
+    git \
+    ca-certificates \
+    curl \
+    gdb \
+    lldb \
+ && rm -rf /var/lib/apt/lists/*
+
+ENV CC=clang CXX=clang++
+CMD ["/bin/bash", "-l"]

container.sh

@@ -0,0 +1,131 @@
+#!/bin/sh
+set -e
+
+container_name="libkqueue-dev"
+dev_image="libkqueue-clang-cmake-dev:latest"
+platform="linux/amd64"
+
+# Verbosity
+verbose=0
+
+debug() {
+  if [ "$verbose" -eq 1 ]; then
+    echo "$@"
+  fi
+}
+
+error() {
+  echo "$@" >&2;
+}
+
+# Parse flags
+while [ $# -gt 0 ]; do
+  case "$1" in
+    -v)
+      verbose=1
+      shift
+      ;;
+    start|stop|restart|status)
+      cmd="$1"
+      shift
+      ;;
+    *)
+      echo "Usage: $0 [-v] {start|stop|restart|status}"
+      exit 1
+      ;;
+  esac
+done
+
+[ -z "$cmd" ] && cmd="start"
+
+hash_file() {
+  # portable sha256
+  if command -v sha256sum >/dev/null 2>&1; then
+    sha256sum "$1" | awk '{print $1}'
+  elif command -v shasum >/dev/null 2>&1; then
+    shasum -a 256 "$1" | awk '{print $1}'
+  else
+    # macOS has openssl by default
+    openssl dgst -sha256 "$1" | awk '{print $NF}'
+  fi
+}
+
+image_build() {
+  [ -f Dockerfile ] || { error "no Dockerfile in $(pwd)"; exit 1; }
+  hash=$(hash_file Dockerfile)
+  debug "(re-)building image with $platform -t $dev_image --build-arg IMAGE_FINGERPRINT=$hash ."
+  docker build --platform=$platform -t "$dev_image" --build-arg "IMAGE_FINGERPRINT=$hash" .
+}
+
+run_container() {
+    debug "Starting container '$container_name' with image '$dev_image'"
+    docker run --rm -it \
+      --platform=${platform} \
+      --name "$container_name" \
+      --hostname "$container_name" \
+      -u "$(id -u)":"$(id -g)" \
+      -e HOME=/home/dev \
+      -w /home/dev \
+      -v "$PWD":/home/dev \
+      "$dev_image"
+}
+
+start_container() {
+  expected=$(hash_file Dockerfile)
+  current=$(docker image inspect "$dev_image" \
+            --format '{{ index .Config.Labels "dev.fingerprint" }}' 2>/dev/null || true)
+
+  if [ -z "$current" ]; then
+    debug "Image missing or unlabeled, building"
+    image_build
+    run_container
+  fi
+
+  if [ "$current" != "$expected" ]; then
+    debug "fingerprint changed ($current -> $expected), rebuilding"
+    image_build
+    docker rm -f "$container_name"
+    start_container
+  fi
+
+  if ! docker ps -a --format '{{.Names}}' | grep -q "^${container_name}$"; then
+    run_container
+  else
+    debug "Getting shell on existing container '$container_name'"
+    docker exec -it ${container_name} /bin/bash
+  fi
+}
+
+stop_container() {
+  if docker ps -a --format '{{.Names}}' | grep -q "^${container_name}$"; then
+    debug "Stopping and removing container '$container_name'"
+    docker rm -f "$container_name" > /dev/null
+  else
+    debug "Container '$container_name' is not running"
+  fi
+}
+
+status_container() {
+  if docker ps --format '{{.Names}}' | grep -q "^${container_name}$"; then
+    echo "Container '$container_name' is running"
+  else
+    echo "Container '$container_name' is not running"
+    exit 1
+  fi
+}
+
+case "$cmd" in
+  start)
+    start_container
+    ;;
+  stop)
+    stop_container
+    ;;
+  restart)
+    stop_container
+    start_container
+    ;;
+  status)
+    status_container
+    ;;
+esac