Pull in go-flags, modified to build on Solaris

github.com/jessevdk/go-flags/command.go

@@ -0,0 +1,84 @@
+package flags
+
+// Command represents an application command. Commands can be added to the
+// parser (which itself is a command) and are selected/executed when its name
+// is specified on the command line. The Command type embeds a Group and
+// therefore also carries a set of command specific options.
+type Command struct {
+	// Embedded, see Group for more information
+	*Group
+
+	// The name by which the command can be invoked
+	Name string
+
+	// The active sub command (set by parsing) or nil
+	Active *Command
+
+	commands            []*Command
+	hasBuiltinHelpGroup bool
+}
+
+// Commander is an interface which can be implemented by any command added in
+// the options. When implemented, the Execute method will be called for the last
+// specified (sub)command providing the remaining command line arguments.
+type Commander interface {
+	// Execute will be called for the last active (sub)command. The
+	// args argument contains the remaining command line arguments. The
+	// error that Execute returns will be eventually passed out of the
+	// Parse method of the Parser.
+	Execute(args []string) error
+}
+
+// Usage is an interface which can be implemented to show a custom usage string
+// in the help message shown for a command.
+type Usage interface {
+	// Usage is called for commands to allow customized printing of command
+	// usage in the generated help message.
+	Usage() string
+}
+
+// AddCommand adds a new command to the parser with the given name and data. The
+// data needs to be a pointer to a struct from which the fields indicate which
+// options are in the command. The provided data can implement the Command and
+// Usage interfaces.
+func (c *Command) AddCommand(command string, shortDescription string, longDescription string, data interface{}) (*Command, error) {
+	cmd := newCommand(command, shortDescription, longDescription, data)
+
+	if err := cmd.scan(); err != nil {
+		return nil, err
+	}
+
+	c.commands = append(c.commands, cmd)
+	return cmd, nil
+}
+
+// AddGroup adds a new group to the command with the given name and data. The
+// data needs to be a pointer to a struct from which the fields indicate which
+// options are in the group.
+func (c *Command) AddGroup(shortDescription string, longDescription string, data interface{}) (*Group, error) {
+	group := newGroup(shortDescription, longDescription, data)
+
+	if err := group.scanType(c.scanSubCommandHandler(group)); err != nil {
+		return nil, err
+	}
+
+	c.groups = append(c.groups, group)
+	return group, nil
+}
+
+// Commands returns a list of subcommands of this command.
+func (c *Command) Commands() []*Command {
+	return c.commands
+}
+
+// Find locates the subcommand with the given name and returns it. If no such
+// command can be found Find will return nil.
+func (c *Command) Find(name string) *Command {
+	for _, cc := range c.commands {
+		if cc.Name == name {
+			return cc
+		}
+	}
+
+	return nil
+}