From 160abf9684ceb2d80c40139a982915fa007e58df Mon Sep 17 00:00:00 2001
From: "W. Trevor King" <wking@tremily.us>
Date: Thu, 15 Sep 2016 21:56:16 -0700
Subject: [PATCH 1/2] Makefile: Add a pattern rule for oci-* commands

Make it easy to (re)build a single command without building all of
them.  Using main.go as the only prerequisite cuts some corners, but
prerequisites for this are hard ;).  With this commit, you can touch
main.go to force a rebuild.  If that ends up being too awkward, we can
make these .PHONY targets.

Signed-off-by: W. Trevor King <wking@tremily.us>
---
 Makefile | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/Makefile b/Makefile
index 73116f7..b67cf09 100644
--- a/Makefile
+++ b/Makefile
@@ -4,6 +4,10 @@ export GO15VENDOREXPERIMENT
 COMMIT=$(shell git rev-parse HEAD 2> /dev/null || true)
 
 EPOCH_TEST_COMMIT ?= v0.2.0
+TOOLS := \
+	oci-create-runtime-bundle \
+	oci-image-validate \
+	oci-unpack
 
 default: help
 
@@ -20,10 +24,10 @@ check-license:
 	@echo "checking license headers"
 	@./.tool/check-license
 
-tools:
-	go build -ldflags "-X main.gitCommit=${COMMIT}" ./cmd/oci-create-runtime-bundle
-	go build -ldflags "-X main.gitCommit=${COMMIT}" ./cmd/oci-unpack
-	go build -ldflags "-X main.gitCommit=${COMMIT}" ./cmd/oci-image-validate
+tools: $(TOOLS)
+
+oci-%: cmd/oci-%/main.go
+	go build -ldflags "-X main.gitCommit=${COMMIT}" ./cmd/$@
 
 lint:
 	@echo "checking lint"
@@ -69,10 +73,7 @@ install.tools: .install.gitvalidation .install.glide .install.glide-vc .install.
 	gometalinter --install --update
 
 clean:
-	rm -rf *~ $(OUTPUT_DIRNAME)
-	rm -f oci-create-runtime-bundle
-	rm -f oci-unpack
-	rm -f oci-image-validate
+	rm -rf *~ $(OUTPUT_DIRNAME) $(TOOLS)
 
 .PHONY: \
 	tools \

From 2d06368186ec4ba216c8afbe6ec59b8d9ad88981 Mon Sep 17 00:00:00 2001
From: "W. Trevor King" <wking@tremily.us>
Date: Thu, 22 Sep 2016 10:10:15 -0700
Subject: [PATCH 2/2] Makefile: Always rebuild oci-* tools

The previous commit only rebuilt them when the associated main.go was
newer, which avoided some unnecessary rebuilds.  Unfortunately, it
also avoids rebuilding when another Go dependency changed, which could
bite users that expected 'make tools' to give them fresh copies of the
tools even if they only touched a dependency package.  I'm fine either
way, but Antonio prefers always rebuilding [1], so this commit adds it.

I've switched the old pattern rule to a static pattern rule [2],
because Make was treating the non-static pattern rules as implicit
rules and .PHONY causes implicit rules to be skipped [3].

[1]: https://github.com/opencontainers/image-tools/pull/28#issuecomment-248958814
[2]: https://www.gnu.org/software/make/manual/html_node/Static-Usage.html
[3]: https://www.gnu.org/software/make/manual/html_node/Phony-Targets.html

Signed-off-by: W. Trevor King <wking@tremily.us>
---
 Makefile | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index b67cf09..f0f35f7 100644
--- a/Makefile
+++ b/Makefile
@@ -26,7 +26,7 @@ check-license:
 
 tools: $(TOOLS)
 
-oci-%: cmd/oci-%/main.go
+$(TOOLS): oci-%:
 	go build -ldflags "-X main.gitCommit=${COMMIT}" ./cmd/$@
 
 lint:
@@ -77,6 +77,7 @@ clean:
 
 .PHONY: \
 	tools \
+	$(TOOLS) \
 	check-license \
 	clean \
 	lint \