add docker as a build system

.dockerignore

@@ -0,0 +1,2 @@
+.git
+.github

Dockerfile

@@ -0,0 +1,20 @@
+FROM ubuntu:22.04 AS build
+ARG USER_ID
+ARG GROUP_ID
+ARG USER_NAME
+ARG GROUP_NAME
+
+ENV DEBIAN_FRONTEND noninteractive
+
+RUN apt-get update \
+&&  apt-get install -y \
+        build-essential \
+        git \
+        libssl-dev \
+        libcurl4-openssl-dev \
+        libsdl2-dev
+
+RUN groupadd -g ${GROUP_ID} ${GROUP_NAME} || true \
+;   useradd -u ${USER_ID} -g ${GROUP_ID} -d ${HOME} -m -s /bin/bash ${USER_NAME} \
+;   echo "${USER_NAME} ALL = (ALL) NOPASSWD: ALL" > /etc/sudoers.d/${USER_NAME} \
+;   install -m 700 -o ${USER_NAME} -g ${GROUP_NAME} -d /run/user/${USER_NAME}

Makefile

@@ -186,5 +186,19 @@ install: $(PROGS)
 clean:
 	rm -f *.o *.d *~ $(PROGS) $(LIBS) slirp/*.o slirp/*.d slirp/*~
 
+docker-image:
+	docker build \
+		--build-arg "USER_ID=$(shell id -u)" \
+		--build-arg "USER_NAME=$(shell id -un)" \
+		--build-arg "GROUP_ID=$(shell id -g)" \
+		--build-arg "GROUP_NAME=$(shell id -gn)" \
+		-t tinyemu-build .
+
+docker-build:
+	docker run --rm -it \
+		--user $(shell id -u):$(shell id -g) \
+		-v .:/io tinyemu-build \
+		/bin/bash -c "cd /io && make temu$(EXE)"
+
 -include $(wildcard *.d)
 -include $(wildcard slirp/*.d)