Replace build script with go version

build/build.go

@@ -0,0 +1,64 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"os/exec"
+	"strings"
+	"time"
+)
+
+var sha = flag.String("sha", "", "SHA of current commit")
+
+func main() {
+	flag.Parse()
+	flags := fmt.Sprintf(`-s -w -X main.SHA="%s" -X main.BuildTime=%d`, getVersion(), time.Now().Unix())
+	pkg := "github.com/StackExchange/dnscontrol"
+
+	build := func(out, goos string) {
+		log.Printf("Building %s", out)
+		cmd := exec.Command("go", "build", "-o", out, "-ldflags", flags, pkg)
+		os.Setenv("GOOS", goos)
+		cmd.Stderr = os.Stderr
+		cmd.Stdout = os.Stdout
+		err := cmd.Run()
+		if err != nil {
+			log.Fatal(err)
+		}
+	}
+
+	build("dnscontrol-Linux", "linux")
+	build("dnscontrol.exe", "windows")
+	build("dnscontrol-Darwin", "darwin")
+}
+
+func getVersion() string {
+	if *sha != "" {
+		return *sha
+	}
+	//check teamcity build version
+	if v := os.Getenv("BUILD_VCS_NUMBER"); v != "" {
+		return v
+	}
+	//check git
+	cmd := exec.Command("git", "rev-parse", "HEAD")
+	v, err := cmd.CombinedOutput()
+	if err != nil {
+		return ""
+	}
+	ver := strings.TrimSpace(string(v))
+	//see if dirty
+	cmd = exec.Command("git", "diff-index", "--quiet", "HEAD", "--")
+	err = cmd.Run()
+	// exit status 1 indicates dirty tree
+	if err != nil {
+		if err.Error() == "exit status 1" {
+			ver += "[dirty]"
+		} else {
+			log.Printf("!%s!", err.Error())
+		}
+	}
+	return ver
+}