Do not build if nothing to do

This commit is contained in:
Jason A. Donenfeld 2018-10-12 01:12:00 +02:00
parent 5d6083df7e
commit fddb949002

View file

@ -1,26 +1,33 @@
PREFIX ?= /usr
DESTDIR ?=
BINDIR ?= $(PREFIX)/bin
ifeq ($(shell go env GOOS),linux)
ifeq ($(wildcard .git),)
$(error Do not build this for Linux. Instead use the Linux kernel module. See wireguard.com/install/ for more info.)
else
$(shell printf 'package main\nconst UseTheKernelModuleInstead = 0xdeadbabe\n' > ireallywantobuildon_linux.go)
endif
endif
export GOPATH ?= $(CURDIR)/.gopath
all: wireguard-go
default: generate-version-and-build
version.go:
ifeq ($(shell go env GOOS)|$(wildcard .git),linux|)
$(error Do not build this for Linux. Instead use the Linux kernel module. See wireguard.com/install/ for more info.)
else
ireallywantobuildon_linux.go:
@printf "WARNING: This software is meant for use on non-Linux\nsystems. For Linux, please use the kernel module\ninstead. See wireguard.com/install/ for more info.\n\n" >&2
@printf 'package main\nconst UseTheKernelModuleInstead = 0xdeadbabe\n' > "$@"
clean-ireallywantobuildon_linux.go:
@rm -f ireallywantobuildon_linux.go
.PHONY: clean-ireallywantobuildon_linux.go
clean: clean-ireallywantobuildon_linux.go
wireguard-go: ireallywantobuildon_linux.go
endif
MAKEFLAGS += --no-print-directory
generate-version-and-build:
@export GIT_CEILING_DIRECTORIES="$(realpath $(CURDIR)/..)" && \
tag="$$(git describe --dirty 2>/dev/null)" && \
ver="$$(printf 'package main\nconst WireGuardGoVersion = "%s"\n' "$$tag")" && \
[ "$$(cat $@ 2>/dev/null)" != "$$ver" ] && \
echo "$$ver" > $@ && \
git update-index --assume-unchanged $@ || true
[ "$$(cat version.go 2>/dev/null)" != "$$ver" ] && \
echo "$$ver" > version.go && \
git update-index --assume-unchanged version.go || true
@$(MAKE) wireguard-go
wireguard-go: $(wildcard *.go) $(wildcard */*.go)
go build -v -o "$@"
@ -31,4 +38,4 @@ install: wireguard-go
clean:
rm -f wireguard-go
.PHONY: clean install version.go
.PHONY: default clean install generate-version-and-build