Add build-dist packaging script; update Building docs

This initial packaging script creates a release-ready tarball for
Unix-alikes. Windows support will be added in a separate commit.

Signed-off-by: Josh Cepek <josh.cepek@usa.net>

build/Building.md

@@ -1,38 +1,34 @@
 Building Easy-RSA 3
 ===
 
-Until a formal buildscript is available, this document serves as the build
-reference. Note that Windows builds require external binary files from the
-unxutils and mksh/Win32 projects which are not included in the Easy-RSA source
-tree.
+This document serves as the packaging reference.
 
-Basic Builds
+Using the buildscript
 ---
 
-This build sequence applies to all platforms, including Windows.
+build/build-dist.sh prepares a release-ready tarball from the current source
+tree. Ensure a clean checkout (remove your left-over temp files) and verify
+release changes are in order:
 
-1. Checkout the release tag of interest
+ * ChangeLog updated for version, date, & feature changes
+ * Release-tag prepared in git
 
-2. Create a target directory named EasyRSA-3.x.y (matching the release version)
+When ready, set a match version on the tarball & inside dir with:
 
-3. Copy the `easyrsa3/*` structure to the target dir root (not named easyrsa3)
+    ./build/build-dist.sh --version=3.2.1
 
-4. Copy the following files/dirs into the target dir:
-
-   * `Licensing/`
-   * `doc/`
-   * `COPYING`
-   * `ChangeLog`
-   * `README.quickstart.md`
-
-5. For Windows, continue to `Windows Build Extras`. Otherwise, tar up the target
-   directory for release distribution.
+For development use, omitting the --version param creates by default a
+`git-development` version.
 
 Windows Build Extras
 ---
 
-Windows has additional build steps to provide a suitable POSIX environment.
-Starting with a basic build dir from earlier, proceed as follows.
+When the build-script is updated to support Windows, this section will be
+updated to match.
+
+Note that Windows builds require external binary files from the unxutils and
+mksh/Win32 projects which are not included in the Easy-RSA source tree. Starting
+with a basic build dir from earlier, proceed as follows.
 
 1. Copy everything from `distro/windows/` into the target dir root. Make sure
    that text files follow the Windows EOL convention (CR+LF) -- a git checkout

build/build-dist.sh

@@ -0,0 +1,116 @@
+#!/bin/sh
+
+# Easy-RSA 3 distribution packager:
+# creates ready-to-use tarball files for Unixes
+
+# operational defaults (CLI processing overrides)
+VERSION="git-development"
+PRODUCT="EasyRSA"
+DIST_ROOT="dist-staging"
+SRC_ROOT="."
+BIN_DEST="."
+
+usage() {
+	echo "build-dist options:"
+	echo
+	echo " --version=X	set version string, default=git-development"
+	echo " --dist-root=X	set DIST_ROOT, default=dist-staging"
+	echo " --src-root=X	set SRC_ROOT for git src dir, default=."
+	echo " --bin-dest=X	set BIN_DEST where to put tar/zip, default=."
+	echo
+	echo " --dist-clean	rm -rf the DIST_ROOT w/out prompts"
+
+	exit
+}
+
+die() {
+	echo "build-dist ERROR:"
+	echo "$1"
+	exit "${2:-1}"
+}
+
+note() { echo "build-dist NOTE: $1"; }
+
+# ask before dangerous things
+confirm() {
+	[ "$2" ] && return
+	echo "$1"
+	printf " y/n: "
+	read r
+	[ "$r" = "y" ] || die "user abort"
+}
+
+# main handling entry, run after options parsing:
+main() {
+	PV="$PRODUCT-$VERSION"
+
+	dist_clean
+	stage_files
+	make_tar
+}
+
+# prep DIST_ROOT
+dist_clean() {
+	if [ -e "$DIST_ROOT" ]; then
+		confirm "Remove existing DIST_ROOT at: '$DIST_ROOT' ?" \
+			"$DISTCLEAN"
+		rm -rf "$DIST_ROOT" || die "dist_clean failed to rm"
+	fi
+	mkdir -p "$DIST_ROOT" || die "dist_clean failed to mkdir"
+}
+
+# file stager
+stage_files() {
+	# Copy files into $PV, starting with easyrsa3 as the initial root dir
+	src_files="easyrsa3/ Licensing/ doc/ COPYING ChangeLog README.quickstart.md"
+	for f in $src_files
+	do
+		cp -a "$SRC_ROOT/$f" "$DIST_ROOT/$PV" || die "failed to copy $f"
+	done
+
+	# files not included
+	rm "$DIST_ROOT/$PV/doc/TODO" || die "failed rm TODO"
+}
+
+make_tar() {
+	(cd "$DIST_ROOT"; tar cz "$PV") > "$BIN_DEST/${PV}.tgz" || die "tar failed"
+	note "tarball created at: $BIN_DEST/${PV}.tgz" 
+}
+
+# parse CLI options:
+while [ -n "$1" ]
+do
+	cmd="${1%%=*}"
+	val="${1#*=}"
+	[ "$1" = "$cmd" ] && val=
+	case "$cmd" in
+		--version)
+			[ -z "$val" ] && die "empty $cmd not allowed"
+			VERSION="$val"
+			;;
+		--dist-root)
+			[ -z "$val" ] && die "empty $cmd not allowed"
+			DIST_ROOT="$val"
+			;;
+		--src-root)
+			[ -z "$val" ] && die "empty $cmd not allowed"
+			SRC_ROOT="$val"
+			;;
+		--bin-dest)
+			[ -z "$val" ] && die "empty $cmd not allowed"
+			BIN_DEST="$val"
+			;;
+		--dist-clean)
+			DISTCLEAN=1
+			;;
+		help|-h|--help|-help)
+			usage
+			;;
+		*)
+			die "Unknown option: $1"
+			;;
+	esac
+	shift
+done
+
+main