Add --version flags to tools.

Change-Id: I1c86c3de09fb59bc20539f7d1efbd4d4710bf494

Makefile

@@ -1,5 +1,5 @@
 all:
-	go install `pkg-config --libs sqlite3 1>/dev/null 2>/dev/null && echo "--tags=with_sqlite"` ./pkg/... ./server/... ./cmd/... ./third_party/...
+	go install --ldflags="-X camlistore.org/pkg/buildinfo.GitInfo "`git log --pretty=format:'%ad-%h' --abbrev-commit --date=short -1` `pkg-config --libs sqlite3 1>/dev/null 2>/dev/null && echo "--tags=with_sqlite"` ./pkg/... ./server/... ./cmd/... ./third_party/...
 
 # Workaround Go bug where the $GOPATH/pkg cache doesn't know about tag changes.
 # Useful when you accidentally run "make" and then "make presubmit" doesn't work.

cmd/camget/camget.go

@@ -48,6 +48,7 @@ import (
 	"path/filepath"
 
 	"camlistore.org/pkg/blobref"
+	"camlistore.org/pkg/buildinfo"
 	"camlistore.org/pkg/cacher"
 	"camlistore.org/pkg/client"
 	"camlistore.org/pkg/httputil"
@@ -56,6 +57,7 @@ import (
 )
 
 var (
+	flagVersion  = flag.Bool("version", false, "show version")
 	flagVerbose  = flag.Bool("verbose", false, "be verbose")
 	flagHTTP     = flag.Bool("verbose_http", false, "show HTTP request summaries")
 	flagCheck    = flag.Bool("check", false, "just check for the existence of listed blobs; returning 0 if all are present")
@@ -69,6 +71,11 @@ func main() {
 	client.AddFlags()
 	flag.Parse()
 
+	if *flagVersion {
+		fmt.Fprintf(os.Stderr, "camget version: %s\n", buildinfo.Version())
+		return
+	}
+
 	if *flagGraph && flag.NArg() != 1 {
 		log.Fatalf("The --graph option requires exactly one parameter.")
 	}

cmd/camput/camput.go

@@ -25,6 +25,7 @@ import (
 	"os"
 	"sort"
 
+	"camlistore.org/pkg/buildinfo"
 	"camlistore.org/pkg/client"
 	"camlistore.org/pkg/httputil"
 	"camlistore.org/pkg/jsonsign"
@@ -33,6 +34,7 @@ import (
 const buffered = 16 // arbitrary
 
 var (
+	flagVersion = flag.Bool("version", false, "show version")
 	flagHelp    = flag.Bool("help", false, "print usage")
 	flagVerbose = flag.Bool("verbose", false, "extra debug logging")
 	flagHTTP    = flag.Bool("verbose_http", false, "show HTTP request summaries")
@@ -225,6 +227,10 @@ var (
 
 // camputMain is separated from main for testing from camput
 func camputMain(args ...string) {
+	if *flagVersion {
+		fmt.Fprintf(stderr, "camget version: %s\n", buildinfo.Version())
+		return
+	}
 	if *flagHelp {
 		usage("")
 	}

pkg/buildinfo/buildinfo.go

@@ -0,0 +1,10 @@
+package buildinfo
+
+var GitInfo string
+
+func Version() string {
+	if GitInfo != "" {
+		return GitInfo
+	}
+	return "unknown" // TODO: show binary's date?
+}

server/camlistored/camlistored.go

@@ -21,6 +21,7 @@ import (
 	"crypto/rsa"
 	"crypto/x509"
 	"crypto/x509/pkix"
+	"database/sql"
 	"encoding/json"
 	"encoding/pem"
 	"flag"
@@ -36,8 +37,8 @@ import (
 	"strings"
 	"syscall"
 	"time"
-	"database/sql"
 
+	"camlistore.org/pkg/buildinfo"
 	"camlistore.org/pkg/jsonsign"
 	"camlistore.org/pkg/osutil"
 	"camlistore.org/pkg/serverconfig"
@@ -70,6 +71,7 @@ const (
 )
 
 var (
+	flagVersion    = flag.Bool("version", false, "show version")
 	flagConfigFile = flag.String("configfile", "",
 		"Config file to use, relative to the Camlistore configuration directory root. If blank, the default is used or auto-generated.")
 	listenFlag = flag.String("listen", "", "host:port to listen on, or :0 to auto-select. If blank, the value in the config will be used instead.")
@@ -351,6 +353,11 @@ func listenAndBaseURL(config *serverconfig.Config) (listen, baseURL string) {
 func main() {
 	flag.Parse()
 
+	if *flagVersion {
+		fmt.Fprintf(os.Stderr, "camlistored version: %s\n", buildinfo.Version())
+		return
+	}
+
 	fileName, err := findConfigFile(*flagConfigFile)
 	if err != nil {
 		exitf("Error finding config file %q: %v", fileName, err)