lix-releng-staging/src/nix/command.hh

61 lines
1.3 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

#pragma once
#include "args.hh"
namespace nix {
/* A command is an argument parser that can be executed by calling its
run() method. */
struct Command : virtual Args
{
virtual std::string name() = 0;
virtual void prepare() { };
virtual void run() = 0;
};
class Store;
/* A command that require a Nix store. */
struct StoreCommand : virtual Command
{
bool reserveSpace;
StoreCommand(bool reserveSpace = true)
: reserveSpace(reserveSpace) { };
void run() override;
virtual void run(ref<Store>) = 0;
};
typedef std::map<std::string, ref<Command>> Commands;
/* An argument parser that supports multiple subcommands,
i.e. <command> <subcommand>. */
class MultiCommand : virtual Args
{
public:
Commands commands;
std::shared_ptr<Command> command;
MultiCommand(const Commands & commands);
void printHelp(const string & programName, std::ostream & out) override;
bool processFlag(Strings::iterator & pos, Strings::iterator end) override;
bool processArgs(const Strings & args, bool finish) override;
};
/* A helper class for registering commands globally. */
struct RegisterCommand
{
static Commands * commands;
RegisterCommand(ref<Command> command)
{
if (!commands) commands = new Commands;
commands->emplace(command->name(), command);
}
};
}