// Copyright (C) 2015-2025 Internet Systems Consortium, Inc. ("ISC")

//

// This Source Code Form is subject to the terms of the Mozilla Public

// License, v. 2.0. If a copy of the MPL was not distributed with this

// file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef UNIX_COMMAND_MGR_H

#define UNIX_COMMAND_MGR_H

#include <asiolink/io_service.h>

#include <cc/data.h>

#include <config/unix_command_config.h>

#include <exceptions/exceptions.h>

#include <boost/noncopyable.hpp>

#include <boost/shared_ptr.hpp>

namespace isc {

namespace config {

/// @brief An exception indicating a problem with socket operation

class SocketError : public Exception {

public:

    SocketError(const char* file, size_t line, const char* what) :

        isc::Exception(file, line, what) { }

};

class UnixCommandMgrImpl;

/// @brief Unix Commands Manager implementation for the Kea servers.

///

/// This class receives and responds to commands over unix domain sockets.

class UnixCommandMgr : public boost::noncopyable {

public:

    /// @brief UnixCommandMgr is a singleton class. This method

    /// returns reference to its sole instance.

    ///

    /// @return the only existing instance of the manager.

    static UnixCommandMgr& instance();

    /// @brief Sets IO service to be used by the unix command manager.

    ///

    /// The server should use this method to provide the Unix Command

    /// Manager with the common IO service used by the server.

    /// @param io_service Pointer to the IO service.

    void setIOService(const asiolink::IOServicePtr& io_service);

    /// @brief Override default connection timeout.

    ///

    /// @param timeout New connection timeout in milliseconds.

    void setConnectionTimeout(const long timeout);

    /// @brief Use external sockets flag.

    ///

    /// Add sockets as external sockets of the interface manager

    /// so available I/O on them makes a waiting select to return.

    ///

    /// @param use_external True (default) add external sockets.

    void addExternalSockets(bool use_external = true);

    /// @brief Opens unix control socket with parameters specified in socket_info

    /// (required parameters: socket-type: unix, socket-name:/unix/path).

    ///

    /// @throw BadSocketInfo When socket configuration is invalid.

    /// @throw SocketError When socket operation fails.

    ///

    /// @param config Configuration information for the unix control socket.

    void openCommandSockets(const isc::data::ConstElementPtr config);

    /// @brief Opens unix control socket with parameters specified in socket_info

    /// (required parameters: socket-type: unix, socket-name:/unix/path).

    ///

    /// Creates acceptor, or reuses the existing one.

    ///

    /// @note This function in used internally by @ref openCommandSockets and it

    /// should not be used directly, except for unit tests.

    ///

    /// @throw BadSocketInfo When socket configuration is invalid.

    /// @throw SocketError When socket operation fails.

    ///

    /// @param config Configuration information for the unix control socket.

    void openCommandSocket(const isc::data::ConstElementPtr config);

    /// @brief Shuts down any open unix control sockets.

    ///

    /// @note This function in used internally by @ref closeCommandSockets and it

    /// should not be used directly, except for unit tests.

    ///

    /// @param info Configuration information for the unix control socket.

    void closeCommandSocket(UnixSocketInfoPtr info = UnixSocketInfoPtr());

    /// @brief Shuts down any open unix control sockets.

    void closeCommandSockets();

    /// @brief Returns unix control socket descriptor.

    ///

    /// This method should be used only in tests.

    ///

    /// @param info Configuration information for the unix control socket.

    ///

    /// @return The file descriptor of the specified unix control socket.

    int getControlSocketFD(UnixSocketInfoPtr info = UnixSocketInfoPtr());

private:

    /// @brief Private constructor.

    UnixCommandMgr();

    /// @brief Pointer to the implementation of the @ref UnixCommandMgr.

    boost::shared_ptr<UnixCommandMgrImpl> impl_;

};

} // end of isc::config namespace

} // end of isc namespace

#endif