build-statics

#!/bin/bash

# Based on http://blog.assarbad.net/20140415/fully-static-build-of-tmux-using-libc-musl-for-linux/

set -e -u

tmp_list=()

cleanup() {
    if [[ ${#tmp_list[@]} -ge 1 ]]; then
	rm -rf "${tmp_list[@]}"
    fi
}

trap cleanup EXIT

build_root="/vol/build"
archives="$build_root/download"
forest="$build_root/forest"
install_dir="$build_root/install"
build_opt_dir="$build_root/build_opt"
muslcc="$install_dir/bin/musl-gcc"

binaries=(
    tmux
    screen
)

log() {
    local line
    for line in "$@"; do
	printf '%s\n' "$line" 1>&2
    done
}

err() {
    log "$@"
    exit 1
}

write_file() {
    local mode=644 OPTIND opt

    write_file_update=''
    while getopts eLl:m:o: opt; do
	case "$opt" in
	    m ) mode="$OPTARG";;
	    * ) err "bad write_file usage";;
	esac
    done
    
    shift $(($OPTIND - 1))
    [[ $# -ge 1 ]] || err "write_file - missing path argument"
    [[ $# -le 2 ]] || err "write_file - too many arguments"

    local path="$1"
    shift

    # Use temporary to ensure atomic operation on filesystem
    local tmp="$(mktemp "$path.XXXXXXXXXX")"
    tmp_list+=("$tmp")
    cat > "$tmp"
    chmod "$mode" "$tmp"
    mv -f "$tmp" "$path"
}

get_info() {
    local name="$1"

    p_name="$name"
    p_required=()
    p_config_args=()
    p_executable=""
    p_extra_scripts_writer=""
    
    unset p_archive_name p_archive_url p_checksum
    case "$name" in
	musl )
	    p_archive_name="musl.tgz"
	    p_archive_url="http://www.musl-libc.org/releases/musl-1.1.4.tar.gz"
	    p_checksum="658c65ad3c3a9b281a96c5281e75720c758d91fcaae35ab987f2fdfb4f88f5cd"
	    p_config_args=(
		--enable-gcc-wrapper
		--disable-shared
		--prefix="$install_dir"
	    )
	    ;;

	ncurses )
	    p_archive_name="ncurses.tgz"
	    p_archive_url="http://ftp.gnu.org/pub/gnu/ncurses/ncurses-5.9.tar.gz"
	    p_checksum="9046298fb440324c9d4135ecea7879ffed8546dd1b58e59430ea07a4633f563b"
	    p_config_args=(
		--without-ada --without-cxx
		--without-progs --without-manpages
		--disable-db-install --without-tests
		--with-default-terminfo-dir=/usr/share/terminfo
		--with-terminfo-dirs="/etc/terminfo:/lib/terminfo:/usr/share/terminfo"
		--prefix="$install_dir"
		CC="$muslcc"
	    )
	    ;;

	libevent2 )
	    p_archive_name="libevent2.tgz"
	    p_archive_url="https://github.com/downloads/libevent/libevent/libevent-2.0.21-stable.tar.gz"
	    p_checksum="22a530a8a5ba1cb9c080cba033206b17dacd21437762155c6d30ee6469f574f5"
	    p_config_args=(
		--enable-static
		--disable-shared
		--disable-openssl
		--prefix="$install_dir"
		CC="$muslcc"
	    )
	    ;;

	tmux )
	    p_archive_name="tmux.tgz"
	    p_archive_url="http://downloads.sourceforge.net/project/tmux/tmux/tmux-1.9/tmux-1.9a.tar.gz?r=&use_mirror=heanet"
	    p_checksum="c5e3b22b901cf109b20dab54a4a651f0471abd1f79f6039d79b250d21c2733f5"
	    p_required=(ncurses libevent2)
	    p_config_args=(
		--enable-static
		--prefix="$install_dir"
		CC="$muslcc"
		CPPFLAGS="-I$install_dir/include -I$install_dir/include/ncurses"
		LDFLAGS="-L$install_dir/lib"
		#LIBS=-lncurses
	    )
	    p_executable="$name"
	    p_extra_scripts_writer=write_tmux_extra
	    
	    ;;

	screen )
	    p_archive_name="screen.tgz"
	    p_archive_url="http://ftp.gnu.org/gnu/screen/screen-4.2.1.tar.gz"
	    p_checksum="5468545047e301d2b3579f9d9ce00466d14a7eec95ce806e3834a3d6b0b9b080"
	    p_required=(ncurses)
	    p_config_args=(
		--prefix="$install_dir"
		--enable-colors256
		--disable-socket-dir
		CC="$muslcc"
		CPPFLAGS="-I$install_dir/include"
		LDFLAGS="-L$install_dir/lib"
	    )
	    p_executable="$name"
	    p_extra_scripts_writer=write_screen_extra
	    ;;

	* )  err "unknown package name - $name" ;;
    esac
}

declare -A recursion_checks

run_with_info() {
    local cmd="$1" name
    shift

    recursion_checks=()
    for name in "$@"; do
	run_one_with_info "$cmd" "$name"
    done
    
}

run_one_with_info() {
    local cmd="$1" name="$2" required

    if [[ -n "${recursion_checks["$name"]-}" ]]; then
	return
    fi
    recursion_checks["$name"]=1

    run_one_with_info "$cmd" musl 

    get_info "$name"
    if [[ ${#p_required[@]} -ne 0 ]]; then
	for required in "${p_required[@]}"; do
	    run_one_with_info "$cmd" "$required"
	done

	# get info again as the above recurssive call overwrites the globals
	get_info "$name"
    fi

    "$cmd" "$name"
}


get_checksum() {
    local path="$1" sum ignore
    read sum ignore < <(sha256sum "$path")
    printf %s "$sum"
}

failed_fetch=()

fetch_source() {
    local path messages

    path="$archives/$p_archive_name"
    if [[ -f "$path" && "$(get_checksum "$path")" == "$p_checksum" ]]; then
	log "Using already downloaded $p_archive_name"
	return
    fi

    log "Fetching $path from $p_archive_url"
    while true; do
	log ""
	curl -L -o "$path" "$p_archive_url" || break
	log ""
	if [[ ! -f "$path" ]]; then
	    log "failed to create $path"
	    break
	fi
	if [[ ! -s "$path" ]]; then
	    log "$path is empty"
	    break
	fi
	if [[ "$(get_checksum "$path")" != "$p_checksum" ]]; then
	    log "checksum mismatch for $path"
	    break
	fi
	return
    done
    failed_fetch+=("$p_name")
}


build_source() {
    local dir prefix config_args_str i old_config_args

    dir="$forest/$p_name"

    config_args_str="configure"
    for i in "${p_config_args[@]}"; do
	config_args_str+=" $(printf %q "$i")"
    done
    
    if [[ -f "$build_opt_dir/$p_name" ]]; then
	if [[ "$(< "$build_opt_dir/$p_name")" == "$config_args_str" ]]; then
	    log "$p_name is already build"
	    return 0
	fi
    fi

    log "unpacking $p_name"
    rm -rf "$dir"
    mkdir "$dir"
    tar --strip-components=1 -C "$dir" -xzf "$archives/$p_archive_name"

    log "building $p_name"

    (cd "$dir" && ./configure "${p_config_args[@]}" && make && make install) 1>&2

    printf '%s\n' "$config_args_str" > "$build_opt_dir/$p_name"

    log "$p_name is successfully built"
}

write_command_with_service() {
    local name="$1" service_args="$2" suffix="$3" cmd_args="$4" path
    shift
    args="$*"
    path="$install_dir/bin/$name-$suffix"
    log "Creating $path"
    sed -e "s/%NAME%/$name/g" \
	-e "s/%SERVICE_ARGS%/$service_args/g" \
	-e "s/%CMD_ARGS%/$cmd_args/g" <<'EOF' \
	| write_file -m 755 "$path"
#!/bin/sh

set -e -u

get_service_state() {
    service_state="$(systemctl show --property=ActiveState "$service")"
    service_state="${service_state#*=}"
}

service="%NAME%-$USER"
dir="$(dirname "$0")"
get_service_state
if test active != "$service_state"; then
    if test inactive = "$service_state" -o failed = "$service_state"; then
        sudo systemd-run --uid $UID --unit "$service" --service-type=forking \
            "$dir/%NAME%" %SERVICE_ARGS% 2>/dev/null
    fi
    i=0
    while test $i -lt 20; do
        get_service_state
        test activating = "$service_state" || break
        sleep 0.05
        i=$(($i + 1))
    done
fi
exec "$dir/%NAME%" %CMD_ARGS%
EOF
    printf '%s\n' "$path"
}

write_screen_extra() {
    write_command_with_service screen "-d -m" resume "-D -r"
}

write_tmux_extra() {
    write_command_with_service tmux "new-session -d" attach attach
}

print_ready_executables() {
    local name path script
    for name in "${binaries[@]}"; do
	get_info "$name"
	path="$install_dir/bin/$p_executable"
	if [[ -x "$path" ]]; then
	    printf '%s\n' "$path"
	    if [[ -n "$p_extra_scripts_writer" ]]; then
		$p_extra_scripts_writer "$install_dir/bin" 
	    fi
	fi
    done
}

run_setup() {
    local dir

    for dir in "$archives" "$forest" "$install_dir" "$build_opt_dir" ; do
	mkdir -p "$dir"
    done
}

if [[ "$UID" == 0 ]]; then
    if [[ ! -d "$build_root" ]]; then
	tmp="$(mktemp -d "$build_root.XXXXXXXXXX")"
	tmp_list+=("$tmp")
	chown user:user "$tmp"
	chmod 770 "$tmp"
	mv "$tmp" "$build_root"
    fi

    built_binaries="$(sudo -u user -H "$0" "$@")"
    if [[ -n "$built_binaries" ]]; then
	xargs install -t /vol/bin <<< "$built_binaries"
    fi
    exit
fi

build_all=""
usage_error=""

bad_usage() {
    log "$@"
    usage_error=1
}

while getopts as opt; do
    case "$opt" in
	a ) build_all=1;;
	* ) usage_error=1 ;;
    esac
done
shift $(($OPTIND - 1))

if [[ -n "$build_all" ]]; then
    [[ $# -eq 0 ]] || bad_usage "unexpected argument"
else
    [[ $# -ne 0 ]] || bad_usage "list of binaried to build must be given"
fi

[[ -z "$usage_error" ]] || err "Try $0 -h for usage"


run_setup

build_list=()
if [[ -n "$build_all" ]]; then
    build_list+=("${binaries[@]}")
else
    build_list+=("$@")
fi

run_with_info fetch_source "${build_list[@]}"
if [[ ${#failed_fetch[@]} -ne 0 ]]; then
    err "" "Failed to download:" "${failed_fetch[@]}"
fi

run_with_info build_source "${build_list[@]}"

print_ready_executables