src/netconf-client.cpp - CzechLight/netconf-cli - Gitiles

 /*
  * Copyright (C) 2019 CESNET, https://photonics.cesnet.cz/
  *
  * Written by Václav Kubernát <kubernat@cesnet.cz>
  * Written by Jan Kundrát <jan.kundrat@cesnet.cz>
  *
 */

 #include <cstring>
 #include <libyang/Tree_Data.hpp>
 #include <mutex>
 extern "C" {
 #include <nc_client.h>
 }
 #include <sstream>
 #include "netconf-client.hpp"
 #include "UniqueResource.hpp"

 namespace libnetconf {

 namespace impl {

 /** @short Initialization of the libnetconf2 library client

 Just a safe wrapper over nc_client_init and nc_client_destroy, really.
 */
 class ClientInit {
     ClientInit()
     {
         nc_client_init();
         nc_verbosity(NC_VERB_DEBUG);
     }

     ~ClientInit()
     {
         nc_client_destroy();
     }

 public:
     static ClientInit& instance()
     {
         static ClientInit lib;
         return lib;
     }

     ClientInit(const ClientInit&) = delete;
     ClientInit(ClientInit&&) = delete;
     ClientInit& operator=(const ClientInit&) = delete;
     ClientInit& operator=(ClientInit&&) = delete;
 };

 static std::mutex clientOptions;

 inline void custom_free_nc_reply_data(nc_reply_data* reply)
 {
     nc_reply_free(reinterpret_cast<nc_reply*>(reply));
 }
 inline void custom_free_nc_reply_error(nc_reply_error* reply)
 {
     nc_reply_free(reinterpret_cast<nc_reply*>(reply));
 }

 char *ssh_auth_interactive_cb(const char *auth_name, const char *instruction, const char *prompt, int echo, void *priv)
 {
     const auto cb = static_cast<const client::KbdInteractiveCb*>(priv);
     auto res = (*cb)(auth_name, instruction, prompt, echo);
     return ::strdup(res.c_str());
 }

 template <typename Type> using deleter_type_for = void (*)(Type*);
 template <typename Type> deleter_type_for<Type> deleter_for;

 template <> const auto deleter_for<nc_rpc> = nc_rpc_free;
 template <> const auto deleter_for<nc_reply> = nc_reply_free;
 template <> const auto deleter_for<nc_reply_data> = custom_free_nc_reply_data;
 template <> const auto deleter_for<nc_reply_error> = custom_free_nc_reply_error;

 template <typename T>
 using unique_ptr_for = std::unique_ptr<T, decltype(deleter_for<T>)>;

 template <typename T>
 auto guarded(T* ptr)
 {
     return unique_ptr_for<T>(ptr, deleter_for<T>);
 }

 unique_ptr_for<struct nc_reply> do_rpc(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
 {
     uint64_t msgid;
     NC_MSG_TYPE msgtype;

     msgtype = nc_send_rpc(session->session_internal(), rpc.get(), 1000, &msgid);
     if (msgtype == NC_MSG_ERROR) {
         throw std::runtime_error{"Failed to send RPC"};
     }
     if (msgtype == NC_MSG_WOULDBLOCK) {
         throw std::runtime_error{"Timeout sending an RPC"};
     }

     struct nc_reply* raw_reply;
     while (true) {
         msgtype = nc_recv_reply(session->session_internal(), rpc.get(), msgid, 20000, LYD_OPT_DESTRUCT | LYD_OPT_NOSIBLINGS, &raw_reply);
         auto reply = guarded(raw_reply);
         raw_reply = nullptr;

         switch (msgtype) {
         case NC_MSG_ERROR:
             throw std::runtime_error{"Failed to receive an RPC reply"};
         case NC_MSG_WOULDBLOCK:
             throw std::runtime_error{"Timed out waiting for RPC reply"};
         case NC_MSG_REPLY_ERR_MSGID:
             throw std::runtime_error{"Received a wrong reply -- msgid mismatch"};
         case NC_MSG_NOTIF:
             continue;
         default:
             return reply;
         }
     }
     __builtin_unreachable();
 }

 client::ReportedError make_error(unique_ptr_for<struct nc_reply>&& reply)
 {
     if (reply->type != NC_RPL_ERROR) {
         throw std::logic_error{"Cannot extract an error from a non-error server reply"};
     }

     auto errorReply = guarded(reinterpret_cast<struct nc_reply_error*>(reply.release()));

     // TODO: capture the error details, not just that human-readable string
     std::ostringstream ss;
     ss << "Server error:" << std::endl;
     for (uint32_t i = 0; i < errorReply->count; ++i) {
         const auto e = errorReply->err[i];
         ss << " #" << i << ": " << e.message;
         if (e.path) {
             ss << " (XPath " << e.path << ")";
         }
         ss << std::endl;
     }
     return client::ReportedError{ss.str()};
 }

 std::optional<unique_ptr_for<struct nc_reply_data>> do_rpc_data_or_ok(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
 {
     auto x = do_rpc(session, std::move(rpc));

     switch (x->type) {
     case NC_RPL_DATA:
         return guarded(reinterpret_cast<struct nc_reply_data*>(x.release()));
     case NC_RPL_OK:
         return std::nullopt;
     case NC_RPL_ERROR:
         throw make_error(std::move(x));
     default:
         throw std::runtime_error{"Unhandled reply type"};
     }

 }

 unique_ptr_for<struct nc_reply_data> do_rpc_data(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
 {
     auto x = do_rpc_data_or_ok(session, std::move(rpc));
     if (!x) {
         throw std::runtime_error{"Received OK instead of a data reply"};
     }
     return std::move(*x);
 }

 void do_rpc_ok(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
 {
     auto x = do_rpc_data_or_ok(session, std::move(rpc));
     if (x) {
         throw std::runtime_error{"Unexpected DATA reply"};
     }
 }
 }

 namespace client {

 struct nc_session* Session::session_internal()
 {
     return m_session;
 }

 libyang::S_Context Session::libyangContext()
 {
     return std::make_shared<libyang::Context>(nc_session_get_ctx(m_session), nullptr);
 }

 Session::Session(struct nc_session* session)
     : m_session(session)
 {
     impl::ClientInit::instance();
 }

 Session::~Session()
 {
     ::nc_session_free(m_session, nullptr);
 }

 std::unique_ptr<Session> Session::connectPubkey(const std::string& host, const uint16_t port, const std::string& user, const std::string& pubPath, const std::string& privPath)
 {
     impl::ClientInit::instance();

     {
         // FIXME: this is still horribly not enough. libnetconf *must* provide us with something better.
         std::lock_guard lk(impl::clientOptions);
         nc_client_ssh_set_username(user.c_str());
         nc_client_ssh_set_auth_pref(NC_SSH_AUTH_PUBLICKEY, 5);
         nc_client_ssh_add_keypair(pubPath.c_str(), privPath.c_str());
     }
     auto session = std::make_unique<Session>(nc_connect_ssh(host.c_str(), port, nullptr));
     if (!session->m_session) {
         throw std::runtime_error{"nc_connect_ssh failed"};
     }
     return session;
 }

 std::unique_ptr<Session> Session::connectKbdInteractive(const std::string& host, const uint16_t port, const std::string& user, const KbdInteractiveCb& callback)
 {
     impl::ClientInit::instance();

     std::lock_guard lk(impl::clientOptions);
     auto cb_guard = make_unique_resource([user, &callback]() {
         nc_client_ssh_set_username(user.c_str());
         nc_client_ssh_set_auth_pref(NC_SSH_AUTH_INTERACTIVE, 5);
         nc_client_ssh_set_auth_interactive_clb(impl::ssh_auth_interactive_cb, static_cast<void *>(&const_cast<KbdInteractiveCb&>(callback)));
     }, []() {
         nc_client_ssh_set_auth_interactive_clb(nullptr, nullptr);
         nc_client_ssh_set_username(nullptr);
     });

     auto session = std::make_unique<Session>(nc_connect_ssh(host.c_str(), port, nullptr));
     if (!session->m_session) {
         throw std::runtime_error{"nc_connect_ssh failed"};
     }
     return session;
 }

 std::unique_ptr<Session> Session::connectSocket(const std::string& path)
 {
     impl::ClientInit::instance();

     auto session = std::make_unique<Session>(nc_connect_unix(path.c_str(), nullptr));
     if (!session->m_session) {
         throw std::runtime_error{"nc_connect_unix failed"};
     }
     return session;
 }

 std::vector<std::string_view> Session::capabilities() const
 {
     std::vector<std::string_view> res;
     auto caps = nc_session_get_cpblts(m_session);
     while (*caps) {
         res.emplace_back(*caps);
         ++caps;
     }
     return res;
 }

 std::shared_ptr<libyang::Data_Node> Session::get(const std::optional<std::string>& filter)
 {
     auto rpc = impl::guarded(nc_rpc_get(filter ? filter->c_str() : nullptr, NC_WD_ALL, NC_PARAMTYPE_CONST));
     if (!rpc) {
         throw std::runtime_error("Cannot create get RPC");
     }
     auto reply = impl::do_rpc_data(this, std::move(rpc));
     auto dataNode = libyang::create_new_Data_Node(reply->data);
     // TODO: can we do without copying?
     // If we just default-construct a new node (or use the create_new_Data_Node) and then set reply->data to nullptr,
     // there are mem leaks and even libnetconf2 complains loudly.
     return dataNode ? dataNode->dup_withsiblings(1) : nullptr;
 }

 std::string Session::getSchema(const std::string_view identifier, const std::optional<std::string_view> version)
 {
     auto rpc = impl::guarded(nc_rpc_getschema(identifier.data(), version ? version.value().data() : nullptr, nullptr, NC_PARAMTYPE_CONST));
     if (!rpc) {
         throw std::runtime_error("Cannot create get-schema RPC");
     }
     auto reply = impl::do_rpc_data(this, std::move(rpc));

     auto node = libyang::create_new_Data_Node(reply->data)->dup_withsiblings(1);
     auto set = node->find_path("data");
     for (auto node : set->data()) {
         if (node->schema()->nodetype() == LYS_ANYXML) {
             libyang::Data_Node_Anydata anydata(node);
             return anydata.value().str;
         }
     }
     throw std::runtime_error("Got a reply to get-schema, but it didn't contain the required schema");
 }

 std::shared_ptr<libyang::Data_Node> Session::getConfig(const NC_DATASTORE datastore, const std::optional<const std::string> filter)
 {
     auto rpc = impl::guarded(nc_rpc_getconfig(datastore, filter ? filter->c_str() : nullptr, NC_WD_ALL, NC_PARAMTYPE_CONST));
     if (!rpc) {
         throw std::runtime_error("Cannot create get-config RPC");
     }
     auto reply = impl::do_rpc_data(this, std::move(rpc));
     auto dataNode = libyang::create_new_Data_Node(reply->data);
     // TODO: can we do without copying? See Session::get() for details.
     return dataNode ? dataNode->dup_withsiblings(1) : nullptr;
 }

 void Session::editConfig(const NC_DATASTORE datastore,
                          const NC_RPC_EDIT_DFLTOP defaultOperation,
                          const NC_RPC_EDIT_TESTOPT testOption,
                          const NC_RPC_EDIT_ERROPT errorOption,
                          const std::string& data)
 {
     auto rpc = impl::guarded(nc_rpc_edit(datastore, defaultOperation, testOption, errorOption, data.c_str(), NC_PARAMTYPE_CONST));
     if (!rpc) {
         throw std::runtime_error("Cannot create edit-config RPC");
     }
     impl::do_rpc_ok(this, std::move(rpc));
 }

 void Session::copyConfigFromString(const NC_DATASTORE target, const std::string& data)
 {
     auto rpc = impl::guarded(nc_rpc_copy(target, nullptr, target /* yeah, cannot be 0... */, data.c_str(), NC_WD_UNKNOWN, NC_PARAMTYPE_CONST));
     if (!rpc) {
         throw std::runtime_error("Cannot create copy-config RPC");
     }
     impl::do_rpc_ok(this, std::move(rpc));
 }

 void Session::commit()
 {
     auto rpc = impl::guarded(nc_rpc_commit(1, /* "Optional confirm timeout" how do you optional an uint32_t? */ 0, nullptr, nullptr, NC_PARAMTYPE_CONST));
     if (!rpc) {
         throw std::runtime_error("Cannot create commit RPC");
     }
     impl::do_rpc_ok(this, std::move(rpc));
 }

 void Session::discard()
 {
     auto rpc = impl::guarded(nc_rpc_discard());
     if (!rpc) {
         throw std::runtime_error("Cannot create discard RPC");
     }
     impl::do_rpc_ok(this, std::move(rpc));
 }

 std::shared_ptr<libyang::Data_Node> Session::rpc_or_action(const std::string& xmlData)
 {
     auto rpc = impl::guarded(nc_rpc_act_generic_xml(xmlData.c_str(), NC_PARAMTYPE_CONST));
     if (!rpc) {
         throw std::runtime_error("Cannot create generic RPC");
     }
     auto reply = impl::do_rpc_data_or_ok(this, std::move(rpc));
     if (reply) {
         auto dataNode = libyang::create_new_Data_Node((*reply)->data);
         return dataNode->dup_withsiblings(1);
     } else {
         return nullptr;
     }
 }

 void Session::copyConfig(const NC_DATASTORE source, const NC_DATASTORE destination)
 {
     auto rpc = impl::guarded(nc_rpc_copy(destination, nullptr, source, nullptr, NC_WD_UNKNOWN, NC_PARAMTYPE_CONST));
     if (!rpc) {
         throw std::runtime_error("Cannot create copy-config RPC");
     }
     impl::do_rpc_ok(this, std::move(rpc));
 }

 ReportedError::ReportedError(const std::string& what)
     : std::runtime_error(what)
 {
 }

 ReportedError::~ReportedError() = default;
 }
 }
	/*
	* Copyright (C) 2019 CESNET, https://photonics.cesnet.cz/
	*
	* Written by Václav Kubernát <kubernat@cesnet.cz>
	* Written by Jan Kundrát <jan.kundrat@cesnet.cz>
	*
	*/

	#include <cstring>
	#include <libyang/Tree_Data.hpp>
	#include <mutex>
	extern "C" {
	#include <nc_client.h>
	}
	#include <sstream>
	#include "netconf-client.hpp"
	#include "UniqueResource.hpp"

	namespace libnetconf {

	namespace impl {

	/** @short Initialization of the libnetconf2 library client

	Just a safe wrapper over nc_client_init and nc_client_destroy, really.
	*/
	class ClientInit {
	ClientInit()
	{
	nc_client_init();
	nc_verbosity(NC_VERB_DEBUG);
	}

	~ClientInit()
	{
	nc_client_destroy();
	}

	public:
	static ClientInit& instance()
	{
	static ClientInit lib;
	return lib;
	}

	ClientInit(const ClientInit&) = delete;
	ClientInit(ClientInit&&) = delete;
	ClientInit& operator=(const ClientInit&) = delete;
	ClientInit& operator=(ClientInit&&) = delete;
	};

	static std::mutex clientOptions;

	inline void custom_free_nc_reply_data(nc_reply_data* reply)
	{
	nc_reply_free(reinterpret_cast<nc_reply*>(reply));
	}
	inline void custom_free_nc_reply_error(nc_reply_error* reply)
	{
	nc_reply_free(reinterpret_cast<nc_reply*>(reply));
	}

	char ssh_auth_interactive_cb(const char auth_name, const char instruction, const char prompt, int echo, void *priv)
	{
	const auto cb = static_cast<const client::KbdInteractiveCb*>(priv);
	auto res = (*cb)(auth_name, instruction, prompt, echo);
	return ::strdup(res.c_str());
	}

	template <typename Type> using deleter_type_for = void ()(Type);
	template <typename Type> deleter_type_for<Type> deleter_for;

	template <> const auto deleter_for<nc_rpc> = nc_rpc_free;
	template <> const auto deleter_for<nc_reply> = nc_reply_free;
	template <> const auto deleter_for<nc_reply_data> = custom_free_nc_reply_data;
	template <> const auto deleter_for<nc_reply_error> = custom_free_nc_reply_error;

	template <typename T>
	using unique_ptr_for = std::unique_ptr<T, decltype(deleter_for<T>)>;

	template <typename T>
	auto guarded(T* ptr)
	{
	return unique_ptr_for<T>(ptr, deleter_for<T>);
	}

	unique_ptr_for<struct nc_reply> do_rpc(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
	{
	uint64_t msgid;
	NC_MSG_TYPE msgtype;

	msgtype = nc_send_rpc(session->session_internal(), rpc.get(), 1000, &msgid);
	if (msgtype == NC_MSG_ERROR) {
	throw std::runtime_error{"Failed to send RPC"};
	}
	if (msgtype == NC_MSG_WOULDBLOCK) {
	throw std::runtime_error{"Timeout sending an RPC"};
	}

	struct nc_reply* raw_reply;
	while (true) {
	msgtype = nc_recv_reply(session->session_internal(), rpc.get(), msgid, 20000, LYD_OPT_DESTRUCT \| LYD_OPT_NOSIBLINGS, &raw_reply);
	auto reply = guarded(raw_reply);
	raw_reply = nullptr;

	switch (msgtype) {
	case NC_MSG_ERROR:
	throw std::runtime_error{"Failed to receive an RPC reply"};
	case NC_MSG_WOULDBLOCK:
	throw std::runtime_error{"Timed out waiting for RPC reply"};
	case NC_MSG_REPLY_ERR_MSGID:
	throw std::runtime_error{"Received a wrong reply -- msgid mismatch"};
	case NC_MSG_NOTIF:
	continue;
	default:
	return reply;
	}
	}
	__builtin_unreachable();
	}

	client::ReportedError make_error(unique_ptr_for<struct nc_reply>&& reply)
	{
	if (reply->type != NC_RPL_ERROR) {
	throw std::logic_error{"Cannot extract an error from a non-error server reply"};
	}

	auto errorReply = guarded(reinterpret_cast<struct nc_reply_error*>(reply.release()));

	// TODO: capture the error details, not just that human-readable string
	std::ostringstream ss;
	ss << "Server error:" << std::endl;
	for (uint32_t i = 0; i < errorReply->count; ++i) {
	const auto e = errorReply->err[i];
	ss << " #" << i << ": " << e.message;
	if (e.path) {
	ss << " (XPath " << e.path << ")";
	}
	ss << std::endl;
	}
	return client::ReportedError{ss.str()};
	}

	std::optional<unique_ptr_for<struct nc_reply_data>> do_rpc_data_or_ok(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
	{
	auto x = do_rpc(session, std::move(rpc));

	switch (x->type) {
	case NC_RPL_DATA:
	return guarded(reinterpret_cast<struct nc_reply_data*>(x.release()));
	case NC_RPL_OK:
	return std::nullopt;
	case NC_RPL_ERROR:
	throw make_error(std::move(x));
	default:
	throw std::runtime_error{"Unhandled reply type"};
	}

	}

	unique_ptr_for<struct nc_reply_data> do_rpc_data(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
	{
	auto x = do_rpc_data_or_ok(session, std::move(rpc));
	if (!x) {
	throw std::runtime_error{"Received OK instead of a data reply"};
	}
	return std::move(*x);
	}

	void do_rpc_ok(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
	{
	auto x = do_rpc_data_or_ok(session, std::move(rpc));
	if (x) {
	throw std::runtime_error{"Unexpected DATA reply"};
	}
	}
	}

	namespace client {

	struct nc_session* Session::session_internal()
	{
	return m_session;
	}

	libyang::S_Context Session::libyangContext()
	{
	return std::make_shared<libyang::Context>(nc_session_get_ctx(m_session), nullptr);
	}

	Session::Session(struct nc_session* session)
	: m_session(session)
	{
	impl::ClientInit::instance();
	}

	Session::~Session()
	{
	::nc_session_free(m_session, nullptr);
	}

	std::unique_ptr<Session> Session::connectPubkey(const std::string& host, const uint16_t port, const std::string& user, const std::string& pubPath, const std::string& privPath)
	{
	impl::ClientInit::instance();

	{
	// FIXME: this is still horribly not enough. libnetconf must provide us with something better.
	std::lock_guard lk(impl::clientOptions);
	nc_client_ssh_set_username(user.c_str());
	nc_client_ssh_set_auth_pref(NC_SSH_AUTH_PUBLICKEY, 5);
	nc_client_ssh_add_keypair(pubPath.c_str(), privPath.c_str());
	}
	auto session = std::make_unique<Session>(nc_connect_ssh(host.c_str(), port, nullptr));
	if (!session->m_session) {
	throw std::runtime_error{"nc_connect_ssh failed"};
	}
	return session;
	}

	std::unique_ptr<Session> Session::connectKbdInteractive(const std::string& host, const uint16_t port, const std::string& user, const KbdInteractiveCb& callback)
	{
	impl::ClientInit::instance();

	std::lock_guard lk(impl::clientOptions);
	auto cb_guard = make_unique_resource([user, &callback]() {
	nc_client_ssh_set_username(user.c_str());
	nc_client_ssh_set_auth_pref(NC_SSH_AUTH_INTERACTIVE, 5);
	nc_client_ssh_set_auth_interactive_clb(impl::ssh_auth_interactive_cb, static_cast<void *>(&const_cast<KbdInteractiveCb&>(callback)));
	}, []() {
	nc_client_ssh_set_auth_interactive_clb(nullptr, nullptr);
	nc_client_ssh_set_username(nullptr);
	});

	auto session = std::make_unique<Session>(nc_connect_ssh(host.c_str(), port, nullptr));
	if (!session->m_session) {
	throw std::runtime_error{"nc_connect_ssh failed"};
	}
	return session;
	}

	std::unique_ptr<Session> Session::connectSocket(const std::string& path)
	{
	impl::ClientInit::instance();

	auto session = std::make_unique<Session>(nc_connect_unix(path.c_str(), nullptr));
	if (!session->m_session) {
	throw std::runtime_error{"nc_connect_unix failed"};
	}
	return session;
	}

	std::vector<std::string_view> Session::capabilities() const
	{
	std::vector<std::string_view> res;
	auto caps = nc_session_get_cpblts(m_session);
	while (*caps) {
	res.emplace_back(*caps);
	++caps;
	}
	return res;
	}

	std::shared_ptr<libyang::Data_Node> Session::get(const std::optional<std::string>& filter)
	{
	auto rpc = impl::guarded(nc_rpc_get(filter ? filter->c_str() : nullptr, NC_WD_ALL, NC_PARAMTYPE_CONST));
	if (!rpc) {
	throw std::runtime_error("Cannot create get RPC");
	}
	auto reply = impl::do_rpc_data(this, std::move(rpc));
	auto dataNode = libyang::create_new_Data_Node(reply->data);
	// TODO: can we do without copying?
	// If we just default-construct a new node (or use the create_new_Data_Node) and then set reply->data to nullptr,
	// there are mem leaks and even libnetconf2 complains loudly.
	return dataNode ? dataNode->dup_withsiblings(1) : nullptr;
	}

	std::string Session::getSchema(const std::string_view identifier, const std::optional<std::string_view> version)
	{
	auto rpc = impl::guarded(nc_rpc_getschema(identifier.data(), version ? version.value().data() : nullptr, nullptr, NC_PARAMTYPE_CONST));
	if (!rpc) {
	throw std::runtime_error("Cannot create get-schema RPC");
	}
	auto reply = impl::do_rpc_data(this, std::move(rpc));

	auto node = libyang::create_new_Data_Node(reply->data)->dup_withsiblings(1);
	auto set = node->find_path("data");
	for (auto node : set->data()) {
	if (node->schema()->nodetype() == LYS_ANYXML) {
	libyang::Data_Node_Anydata anydata(node);
	return anydata.value().str;
	}
	}
	throw std::runtime_error("Got a reply to get-schema, but it didn't contain the required schema");
	}

	std::shared_ptr<libyang::Data_Node> Session::getConfig(const NC_DATASTORE datastore, const std::optional<const std::string> filter)
	{
	auto rpc = impl::guarded(nc_rpc_getconfig(datastore, filter ? filter->c_str() : nullptr, NC_WD_ALL, NC_PARAMTYPE_CONST));
	if (!rpc) {
	throw std::runtime_error("Cannot create get-config RPC");
	}
	auto reply = impl::do_rpc_data(this, std::move(rpc));
	auto dataNode = libyang::create_new_Data_Node(reply->data);
	// TODO: can we do without copying? See Session::get() for details.
	return dataNode ? dataNode->dup_withsiblings(1) : nullptr;
	}

	void Session::editConfig(const NC_DATASTORE datastore,
	const NC_RPC_EDIT_DFLTOP defaultOperation,
	const NC_RPC_EDIT_TESTOPT testOption,
	const NC_RPC_EDIT_ERROPT errorOption,
	const std::string& data)
	{
	auto rpc = impl::guarded(nc_rpc_edit(datastore, defaultOperation, testOption, errorOption, data.c_str(), NC_PARAMTYPE_CONST));
	if (!rpc) {
	throw std::runtime_error("Cannot create edit-config RPC");
	}
	impl::do_rpc_ok(this, std::move(rpc));
	}

	void Session::copyConfigFromString(const NC_DATASTORE target, const std::string& data)
	{
	auto rpc = impl::guarded(nc_rpc_copy(target, nullptr, target /* yeah, cannot be 0... */, data.c_str(), NC_WD_UNKNOWN, NC_PARAMTYPE_CONST));
	if (!rpc) {
	throw std::runtime_error("Cannot create copy-config RPC");
	}
	impl::do_rpc_ok(this, std::move(rpc));
	}

	void Session::commit()
	{
	auto rpc = impl::guarded(nc_rpc_commit(1, /* "Optional confirm timeout" how do you optional an uint32_t? */ 0, nullptr, nullptr, NC_PARAMTYPE_CONST));
	if (!rpc) {
	throw std::runtime_error("Cannot create commit RPC");
	}
	impl::do_rpc_ok(this, std::move(rpc));
	}

	void Session::discard()
	{
	auto rpc = impl::guarded(nc_rpc_discard());
	if (!rpc) {
	throw std::runtime_error("Cannot create discard RPC");
	}
	impl::do_rpc_ok(this, std::move(rpc));
	}

	std::shared_ptr<libyang::Data_Node> Session::rpc_or_action(const std::string& xmlData)
	{
	auto rpc = impl::guarded(nc_rpc_act_generic_xml(xmlData.c_str(), NC_PARAMTYPE_CONST));
	if (!rpc) {
	throw std::runtime_error("Cannot create generic RPC");
	}
	auto reply = impl::do_rpc_data_or_ok(this, std::move(rpc));
	if (reply) {
	auto dataNode = libyang::create_new_Data_Node((*reply)->data);
	return dataNode->dup_withsiblings(1);
	} else {
	return nullptr;
	}
	}

	void Session::copyConfig(const NC_DATASTORE source, const NC_DATASTORE destination)
	{
	auto rpc = impl::guarded(nc_rpc_copy(destination, nullptr, source, nullptr, NC_WD_UNKNOWN, NC_PARAMTYPE_CONST));
	if (!rpc) {
	throw std::runtime_error("Cannot create copy-config RPC");
	}
	impl::do_rpc_ok(this, std::move(rpc));
	}

	ReportedError::ReportedError(const std::string& what)
	: std::runtime_error(what)
	{
	}

	ReportedError::~ReportedError() = default;
	}
	}