From a624f3dc91e197afe92f7abb5da80690c05ce55f Mon Sep 17 00:00:00 2001
From: Bruce Leidl <bruce@subgraph.com>
Date: Mon, 5 Feb 2018 11:17:22 -0500
Subject: [PATCH] Makefile improved a lot

---
 Makefile  | 28 ++++++++++++++++++++--------
 README.md |  6 +++++-
 2 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/Makefile b/Makefile
index 673ede9..53f7dd4 100644
--- a/Makefile
+++ b/Makefile
@@ -1,17 +1,29 @@
-.PHONY: docker-image docker-shell
+.PHONY: help docker-image docker-shell citadel-image citadel-kernel user-rootfs
 
 BASE_DIR = $(shell pwd)
 BASE_BINDMOUNT = type=bind,source=$(BASE_DIR),target=/home/builder/citadel
+DOCKER_RUN = docker run -it --mount $(BASE_BINDMOUNT) citadel-builder  
+DOCKER_RUN_PRIV = docker run -it --privileged --mount $(BASE_BINDMOUNT) citadel-builder  
 
-all: docker-image docker-shell
+#
+# https://marmelab.com/blog/2016/02/29/auto-documented-makefile.html
+# 
+help:
+	@grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) \
+	| awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'
 
-docker-image:
+docker-image: ## Create docker builder image.  You need to run this one time before running anything else.
 	docker build -t citadel-builder scripts/docker
 
-docker-shell:
-	docker run -it --mount $(BASE_BINDMOUNT) citadel-builder 
+docker-shell: ## Open an interactive shell in the docker build container configured for running bitbake commands.
+	$(DOCKER_RUN)
 
-user-rootfs:
+citadel-image: ## Build citadel-image with bitbake 
+	$(DOCKER_RUN) bash -c "source setup-build-env && bitbake citadel-image"
+
+citadel-kernel: ## Build citadel-kernel with bitbake
+	$(DOCKER_RUN) bash -c "source setup-build-env && bitbake citadel-kernel"
+
+user-rootfs: ## Build user-rootfs tarball with debootstrap and configuration scripts
 	mkdir -p build/debootstrap
-	docker run -it --privileged --mount $(BASE_BINDMOUNT) citadel-builder sudo scripts/build-user-rootfs-stage-one | tee build/debootstrap/build-user-rootfs.log
-
+	$(DOCKER_RUN_PRIV) sudo scripts/build-user-rootfs-stage-one | tee build/debootstrap/build-user-rootfs.log
diff --git a/README.md b/README.md
index 147dde8..30c2f6c 100644
--- a/README.md
+++ b/README.md
@@ -35,6 +35,10 @@ Docker will realize that the Dockerfile has not changed and do nothing.
 
     $ make docker-image
 
+To list available make targets, run `make help` or just `make` as this is the default target:
+
+    $ make help
+
 To run a shell inside the docker build container:
 
     $ make docker-shell
@@ -43,7 +47,7 @@ The shell will run in the build directory and be configured to run build command
 
 To build a full citadel image:
 
-    $ bitbake citadel-image
+    $ make citadel-image
 
 The build will take several hours the first time, but for later builds the build system will use cached artifacts stored 
 in `citadel/build/sstate-cache` for components that have not changed and new builds will usually only take a few minutes.