X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/8f8a0ac695f4440412de0245fc748c2792cb1496..cc952178056bf6d29471f6986306fb673dcf394a:/lib/cmd/cmd.go

diff --git a/lib/cmd/cmd.go b/lib/cmd/cmd.go
index d04006586f..9292ef7e5f 100644
--- a/lib/cmd/cmd.go
+++ b/lib/cmd/cmd.go
@@ -11,6 +11,9 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
+	"path/filepath"
+	"regexp"
+	"runtime"
 	"sort"
 	"strings"
 )
@@ -25,8 +28,17 @@ func (f HandlerFunc) RunCommand(prog string, args []string, stdin io.Reader, std
 	return f(prog, args, stdin, stdout, stderr)
 }
 
-// Multi is a Handler that looks up its first argument in a map, and
-// invokes the resulting Handler with the remaining args.
+type Version string
+
+func (v Version) RunCommand(prog string, args []string, stdin io.Reader, stdout, stderr io.Writer) int {
+	prog = regexp.MustCompile(` -*version$`).ReplaceAllLiteralString(prog, "")
+	fmt.Fprintf(stdout, "%s %s (%s)\n", prog, v, runtime.Version())
+	return 0
+}
+
+// Multi is a Handler that looks up its first argument in a map (after
+// stripping any "arvados-" or "crunch-" prefix), and invokes the
+// resulting Handler with the remaining args.
 //
 // Example:
 //
@@ -41,21 +53,30 @@ func (f HandlerFunc) RunCommand(prog string, args []string, stdin io.Reader, std
 type Multi map[string]Handler
 
 func (m Multi) RunCommand(prog string, args []string, stdin io.Reader, stdout, stderr io.Writer) int {
-	if len(args) < 1 {
+	_, basename := filepath.Split(prog)
+	basename = strings.TrimPrefix(basename, "arvados-")
+	basename = strings.TrimPrefix(basename, "crunch-")
+	if cmd, ok := m[basename]; ok {
+		return cmd.RunCommand(prog, args, stdin, stdout, stderr)
+	} else if len(args) < 1 {
 		fmt.Fprintf(stderr, "usage: %s command [args]\n", prog)
 		m.Usage(stderr)
 		return 2
-	}
-	if cmd, ok := m[args[0]]; !ok {
-		fmt.Fprintf(stderr, "unrecognized command %q\n", args[0])
+	} else if cmd, ok = m[args[0]]; ok {
+		return cmd.RunCommand(prog+" "+args[0], args[1:], stdin, stdout, stderr)
+	} else {
+		fmt.Fprintf(stderr, "%s: unrecognized command %q\n", prog, args[0])
 		m.Usage(stderr)
 		return 2
-	} else {
-		return cmd.RunCommand(prog+" "+args[0], args[1:], stdin, stdout, stderr)
 	}
 }
 
 func (m Multi) Usage(stderr io.Writer) {
+	fmt.Fprintf(stderr, "\nAvailable commands:\n")
+	m.listSubcommands(stderr, "")
+}
+
+func (m Multi) listSubcommands(out io.Writer, prefix string) {
 	var subcommands []string
 	for sc := range m {
 		if strings.HasPrefix(sc, "-") {
@@ -67,9 +88,13 @@ func (m Multi) Usage(stderr io.Writer) {
 		subcommands = append(subcommands, sc)
 	}
 	sort.Strings(subcommands)
-	fmt.Fprintf(stderr, "\nAvailable commands:\n")
 	for _, sc := range subcommands {
-		fmt.Fprintf(stderr, "    %s\n", sc)
+		switch cmd := m[sc].(type) {
+		case Multi:
+			cmd.listSubcommands(out, prefix+sc+" ")
+		default:
+			fmt.Fprintf(out, "    %s%s\n", prefix, sc)
+		}
 	}
 }