src/messages_server.c - github/CESNET/libnetconf2 - Gitiles

 /**
  * @file messages_server.c
  * @author Michal Vasko <mvasko@cesnet.cz>
  * @brief libnetconf2 - server NETCONF messages functions
  *
  * @copyright
  * Copyright (c) 2015 CESNET, z.s.p.o.
  *
  * This source code is licensed under BSD 3-Clause License (the "License").
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     https://opensource.org/licenses/BSD-3-Clause
  */

 #define _GNU_SOURCE /* pthread_rwlock_t, strdup */

 #include <ctype.h>
 #include <inttypes.h>
 #include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>

 #include <libyang/libyang.h>

 #include "compat.h"
 #include "libnetconf.h"
 #include "session_server.h"

 extern struct nc_server_opts server_opts;

 API struct nc_server_reply *
 nc_server_reply_ok(void)
 {
     struct nc_server_reply *ret;

     ret = malloc(sizeof *ret);
     if (!ret) {
         ERRMEM;
         return NULL;
     }

     ret->type = NC_RPL_OK;
     return ret;
 }

 API struct nc_server_reply *
 nc_server_reply_data(struct lyd_node *data, NC_WD_MODE wd, NC_PARAMTYPE paramtype)
 {
     struct nc_server_reply_data *ret;

     if (!data || !(data->schema->nodetype & (LYS_RPC | LYS_ACTION))) {
         ERRARG("data");
         return NULL;
     }

     ret = malloc(sizeof *ret);
     if (!ret) {
         ERRMEM;
         return NULL;
     }

     ret->type = NC_RPL_DATA;
     ret->wd = wd;
     if (paramtype == NC_PARAMTYPE_DUP_AND_FREE) {
         if (lyd_dup_single(data, NULL, LYD_DUP_RECURSIVE, &ret->data)) {
             free(ret);
             return NULL;
         }
     } else {
         ret->data = data;
     }
     if (paramtype != NC_PARAMTYPE_CONST) {
         ret->free = 1;
     } else {
         ret->free = 0;
     }
     return (struct nc_server_reply *)ret;
 }

 API struct nc_server_reply *
 nc_server_reply_err(struct lyd_node *err)
 {
     struct nc_server_reply_error *ret;

     if (!err) {
         ERRARG("err");
         return NULL;
     }

     ret = malloc(sizeof *ret);
     if (!ret) {
         ERRMEM;
         return NULL;
     }

     ret->type = NC_RPL_ERROR;
     ret->err = err;
     return (struct nc_server_reply *)ret;
 }

 API int
 nc_server_reply_add_err(struct nc_server_reply *reply, struct lyd_node *err)
 {
     struct nc_server_reply_error *err_rpl;

     if (!reply || (reply->type != NC_RPL_ERROR)) {
         ERRARG("reply");
         return -1;
     } else if (!err) {
         ERRARG("err");
         return -1;
     }

     err_rpl = (struct nc_server_reply_error *)reply;
     lyd_insert_sibling(err_rpl->err, err, &err_rpl->err);
     return 0;
 }

 API const struct lyd_node *
 nc_server_reply_get_last_err(const struct nc_server_reply *reply)
 {
     struct nc_server_reply_error *err_rpl;

     if (!reply || (reply->type != NC_RPL_ERROR)) {
         ERRARG("reply");
         return NULL;
     }

     err_rpl = (struct nc_server_reply_error *)reply;
     if (!err_rpl->err) {
         return NULL;
     }
     return err_rpl->err->prev;
 }

 static const char *
 nc_err_tag2str(NC_ERR tag)
 {
     switch (tag) {
     case NC_ERR_IN_USE:
         return "in-use";
     case NC_ERR_INVALID_VALUE:
         return "invalid-value";
     case NC_ERR_ACCESS_DENIED:
         return "access-denied";
     case NC_ERR_ROLLBACK_FAILED:
         return "rollback-failed";
     case NC_ERR_OP_NOT_SUPPORTED:
         return "operation-not-supported";
     case NC_ERR_TOO_BIG:
         return "too-big";
     case NC_ERR_RES_DENIED:
         return "resource-denied";
     case NC_ERR_MISSING_ATTR:
         return "missing-attribute";
     case NC_ERR_BAD_ATTR:
         return "bad-attribute";
     case NC_ERR_UNKNOWN_ATTR:
         return "unknown-attribute";
     case NC_ERR_MISSING_ELEM:
         return "missing-element";
     case NC_ERR_BAD_ELEM:
         return "bad-element";
     case NC_ERR_UNKNOWN_ELEM:
         return "unknown-element";
     case NC_ERR_UNKNOWN_NS:
         return "unknown-namespace";
     case NC_ERR_LOCK_DENIED:
         return "lock-denied";
     case NC_ERR_DATA_EXISTS:
         return "data-exists";
     case NC_ERR_DATA_MISSING:
         return "data-missing";
     case NC_ERR_OP_FAILED:
         return "operation-failed";
     case NC_ERR_MALFORMED_MSG:
         return "malformed-message";
     default:
         break;
     }

     return NULL;
 }

 static NC_ERR
 nc_err_str2tag(const char *str)
 {
     if (!strcmp(str, "in-use")) {
         return NC_ERR_IN_USE;
     } else if (!strcmp(str, "invalid-value")) {
         return NC_ERR_INVALID_VALUE;
     } else if (!strcmp(str, "access-denied")) {
         return NC_ERR_ACCESS_DENIED;
     } else if (!strcmp(str, "rollback-failed")) {
         return NC_ERR_ROLLBACK_FAILED;
     } else if (!strcmp(str, "operation-not-supported")) {
         return NC_ERR_OP_NOT_SUPPORTED;
     } else if (!strcmp(str, "too-big")) {
         return NC_ERR_TOO_BIG;
     } else if (!strcmp(str, "resource-denied")) {
         return NC_ERR_RES_DENIED;
     } else if (!strcmp(str, "missing-attribute")) {
         return NC_ERR_MISSING_ATTR;
     } else if (!strcmp(str, "bad-attribute")) {
         return NC_ERR_BAD_ATTR;
     } else if (!strcmp(str, "unknown-attribute")) {
         return NC_ERR_UNKNOWN_ATTR;
     } else if (!strcmp(str, "missing-element")) {
         return NC_ERR_MISSING_ELEM;
     } else if (!strcmp(str, "bad-element")) {
         return NC_ERR_BAD_ELEM;
     } else if (!strcmp(str, "unknown-element")) {
         return NC_ERR_UNKNOWN_ELEM;
     } else if (!strcmp(str, "unknown-namespace")) {
         return NC_ERR_UNKNOWN_NS;
     } else if (!strcmp(str, "lock-denied")) {
         return NC_ERR_LOCK_DENIED;
     } else if (!strcmp(str, "data-exists")) {
         return NC_ERR_DATA_EXISTS;
     } else if (!strcmp(str, "data-missing")) {
         return NC_ERR_DATA_MISSING;
     } else if (!strcmp(str, "operation-failed")) {
         return NC_ERR_OP_FAILED;
     } else if (!strcmp(str, "malformed-message")) {
         return NC_ERR_MALFORMED_MSG;
     }

     return 0;
 }

 static const char *
 nc_err_type2str(NC_ERR_TYPE type)
 {
     switch (type) {
     case NC_ERR_TYPE_TRAN:
         return "transport";
     case NC_ERR_TYPE_RPC:
         return "rpc";
     case NC_ERR_TYPE_PROT:
         return "protocol";
     case NC_ERR_TYPE_APP:
         return "application";
     default:
         break;
     }

     return NULL;
 }

 static NC_ERR_TYPE
 nc_err_str2type(const char *str)
 {
     if (!strcmp(str, "transport")) {
         return NC_ERR_TYPE_TRAN;
     } else if (!strcmp(str, "rpc")) {
         return NC_ERR_TYPE_RPC;
     } else if (!strcmp(str, "protocol")) {
         return NC_ERR_TYPE_PROT;
     } else if (!strcmp(str, "application")) {
         return NC_ERR_TYPE_APP;
     }

     return 0;
 }

 API struct lyd_node *
 nc_err(const struct ly_ctx *ctx, NC_ERR tag, ...)
 {
     va_list ap;
     struct lyd_node *err = NULL;
     NC_ERR_TYPE type;
     const char *arg1, *arg2;
     uint32_t sid;

     if (!tag) {
         ERRARG("tag");
         return NULL;
     }

     /* rpc-error */
     if (lyd_new_opaq2(NULL, ctx, "rpc-error", NULL, NULL, NC_NS_BASE, &err)) {
         return NULL;
     }

     va_start(ap, tag);

     /* error-type */
     switch (tag) {
     case NC_ERR_IN_USE:
     case NC_ERR_INVALID_VALUE:
     case NC_ERR_ACCESS_DENIED:
     case NC_ERR_ROLLBACK_FAILED:
     case NC_ERR_OP_NOT_SUPPORTED:
         type = (NC_ERR_TYPE)va_arg(ap, int); /* NC_ERR_TYPE enum is automatically promoted to int */
         if ((type != NC_ERR_TYPE_PROT) && (type != NC_ERR_TYPE_APP)) {
             ERRARG("type");
             goto fail;
         }
         break;
     case NC_ERR_TOO_BIG:
     case NC_ERR_RES_DENIED:
         type = (NC_ERR_TYPE)va_arg(ap, int);
         break;
     case NC_ERR_MISSING_ATTR:
     case NC_ERR_BAD_ATTR:
     case NC_ERR_UNKNOWN_ATTR:
         type = (NC_ERR_TYPE)va_arg(ap, int);
         if (type == NC_ERR_TYPE_TRAN) {
             ERRARG("type");
             goto fail;
         }
         break;
     case NC_ERR_MISSING_ELEM:
     case NC_ERR_BAD_ELEM:
     case NC_ERR_UNKNOWN_ELEM:
         type = (NC_ERR_TYPE)va_arg(ap, int);
         if ((type != NC_ERR_TYPE_PROT) && (type != NC_ERR_TYPE_APP)) {
             ERRARG("type");
             goto fail;
         }
         break;
     case NC_ERR_UNKNOWN_NS:
         type = (NC_ERR_TYPE)va_arg(ap, int);
         if ((type != NC_ERR_TYPE_PROT) && (type != NC_ERR_TYPE_APP)) {
             ERRARG("type");
             goto fail;
         }
         break;
     case NC_ERR_LOCK_DENIED:
         type = NC_ERR_TYPE_PROT;
         break;
     case NC_ERR_DATA_EXISTS:
     case NC_ERR_DATA_MISSING:
         type = NC_ERR_TYPE_APP;
         break;
     case NC_ERR_OP_FAILED:
         type = (NC_ERR_TYPE)va_arg(ap, int);
         if (type == NC_ERR_TYPE_TRAN) {
             ERRARG("type");
             goto fail;
         }
         break;
     case NC_ERR_MALFORMED_MSG:
         type = NC_ERR_TYPE_RPC;
         break;
     default:
         ERRARG("tag");
         goto fail;
     }
     if (lyd_new_opaq2(err, NULL, "error-type", nc_err_type2str(type), NULL, NC_NS_BASE, NULL)) {
         goto fail;
     }

     /* error-tag */
     if (lyd_new_opaq2(err, NULL, "error-tag", nc_err_tag2str(tag), NULL, NC_NS_BASE, NULL)) {
         goto fail;
     }

     /* error-severity */
     if (lyd_new_opaq2(err, NULL, "error-severity", "error", NULL, NC_NS_BASE, NULL)) {
         goto fail;
     }

     /* error-message */
     switch (tag) {
     case NC_ERR_IN_USE:
         nc_err_set_msg(err, "The request requires a resource that already is in use.", "en");
         break;
     case NC_ERR_INVALID_VALUE:
         nc_err_set_msg(err, "The request specifies an unacceptable value for one or more parameters.", "en");
         break;
     case NC_ERR_TOO_BIG:
         nc_err_set_msg(err, "The request or response (that would be generated) is too large for the implementation to handle.", "en");
         break;
     case NC_ERR_MISSING_ATTR:
         nc_err_set_msg(err, "An expected attribute is missing.", "en");
         break;
     case NC_ERR_BAD_ATTR:
         nc_err_set_msg(err, "An attribute value is not correct.", "en");
         break;
     case NC_ERR_UNKNOWN_ATTR:
         nc_err_set_msg(err, "An unexpected attribute is present.", "en");
         break;
     case NC_ERR_MISSING_ELEM:
         nc_err_set_msg(err, "An expected element is missing.", "en");
         break;
     case NC_ERR_BAD_ELEM:
         nc_err_set_msg(err, "An element value is not correct.", "en");
         break;
     case NC_ERR_UNKNOWN_ELEM:
         nc_err_set_msg(err, "An unexpected element is present.", "en");
         break;
     case NC_ERR_UNKNOWN_NS:
         nc_err_set_msg(err, "An unexpected namespace is present.", "en");
         break;
     case NC_ERR_ACCESS_DENIED:
         nc_err_set_msg(err, "Access to the requested protocol operation or data model is denied because authorization failed.", "en");
         break;
     case NC_ERR_LOCK_DENIED:
         nc_err_set_msg(err, "Access to the requested lock is denied because the lock is currently held by another entity.", "en");
         break;
     case NC_ERR_RES_DENIED:
         nc_err_set_msg(err, "Request could not be completed because of insufficient resources.", "en");
         break;
     case NC_ERR_ROLLBACK_FAILED:
         nc_err_set_msg(err, "Request to roll back some configuration change was not completed for some reason.", "en");
         break;
     case NC_ERR_DATA_EXISTS:
         nc_err_set_msg(err, "Request could not be completed because the relevant data model content already exists.", "en");
         break;
     case NC_ERR_DATA_MISSING:
         nc_err_set_msg(err, "Request could not be completed because the relevant data model content does not exist.", "en");
         break;
     case NC_ERR_OP_NOT_SUPPORTED:
         nc_err_set_msg(err, "Request could not be completed because the requested operation is not supported by this implementation.", "en");
         break;
     case NC_ERR_OP_FAILED:
         nc_err_set_msg(err, "Request could not be completed because the requested operation failed for a non-specific reason.", "en");
         break;
     case NC_ERR_MALFORMED_MSG:
         nc_err_set_msg(err, "A message could not be handled because it failed to be parsed correctly.", "en");
         break;
     default:
         ERRARG("tag");
         goto fail;
     }

     /* error-info */
     switch (tag) {
     case NC_ERR_IN_USE:
     case NC_ERR_INVALID_VALUE:
     case NC_ERR_ACCESS_DENIED:
     case NC_ERR_ROLLBACK_FAILED:
     case NC_ERR_OP_NOT_SUPPORTED:
     case NC_ERR_TOO_BIG:
     case NC_ERR_RES_DENIED:
     case NC_ERR_DATA_EXISTS:
     case NC_ERR_DATA_MISSING:
     case NC_ERR_OP_FAILED:
     case NC_ERR_MALFORMED_MSG:
         break;
     case NC_ERR_MISSING_ATTR:
     case NC_ERR_BAD_ATTR:
     case NC_ERR_UNKNOWN_ATTR:
         arg1 = va_arg(ap, const char *);
         arg2 = va_arg(ap, const char *);

         nc_err_add_bad_attr(err, arg1);
         nc_err_add_bad_elem(err, arg2);
         break;
     case NC_ERR_MISSING_ELEM:
     case NC_ERR_BAD_ELEM:
     case NC_ERR_UNKNOWN_ELEM:
         arg1 = va_arg(ap, const char *);

         nc_err_add_bad_elem(err, arg1);
         break;
     case NC_ERR_UNKNOWN_NS:
         arg1 = va_arg(ap, const char *);
         arg2 = va_arg(ap, const char *);

         nc_err_add_bad_elem(err, arg1);
         nc_err_add_bad_ns(err, arg2);
         break;
     case NC_ERR_LOCK_DENIED:
         sid = va_arg(ap, uint32_t);

         nc_err_set_sid(err, sid);
         break;
     default:
         ERRARG("tag");
         goto fail;
     }

     va_end(ap);
     return err;

 fail:
     va_end(ap);
     lyd_free_siblings(err);
     return NULL;
 }

 API NC_ERR_TYPE
 nc_err_get_type(const struct lyd_node *err)
 {
     struct lyd_node *match;

     if (!err) {
         ERRARG("err");
         return 0;
     }

     lyd_find_sibling_opaq_next(lyd_child(err), "error-type", &match);
     if (match) {
         return nc_err_str2type(((struct lyd_node_opaq *)match)->value);
     }

     return 0;
 }

 API NC_ERR
 nc_err_get_tag(const struct lyd_node *err)
 {
     struct lyd_node *match;

     if (!err) {
         ERRARG("err");
         return 0;
     }

     lyd_find_sibling_opaq_next(lyd_child(err), "error-tag", &match);
     if (match) {
         return nc_err_str2tag(((struct lyd_node_opaq *)match)->value);
     }

     return 0;
 }

 API int
 nc_err_set_app_tag(struct lyd_node *err, const char *error_app_tag)
 {
     struct lyd_node *match;

     if (!err) {
         ERRARG("err");
         return -1;
     } else if (!error_app_tag) {
         ERRARG("error_app_tag");
         return -1;
     }

     /* remove previous node */
     lyd_find_sibling_opaq_next(lyd_child(err), "error-app-tag", &match);
     if (match) {
         lyd_free_tree(match);
     }

     if (lyd_new_opaq2(err, NULL, "error-app-tag", error_app_tag, NULL, NC_NS_BASE, NULL)) {
         return -1;
     }

     return 0;
 }

 API const char *
 nc_err_get_app_tag(const struct lyd_node *err)
 {
     struct lyd_node *match;

     if (!err) {
         ERRARG("err");
         return NULL;
     }

     lyd_find_sibling_opaq_next(lyd_child(err), "error-app-tag", &match);
     if (match) {
         return ((struct lyd_node_opaq *)match)->value;
     }

     return NULL;
 }

 API int
 nc_err_set_path(struct lyd_node *err, const char *error_path)
 {
     struct lyd_node *match;

     if (!err) {
         ERRARG("err");
         return -1;
     } else if (!error_path) {
         ERRARG("error_path");
         return -1;
     }

     /* remove previous node */
     lyd_find_sibling_opaq_next(lyd_child(err), "error-path", &match);
     if (match) {
         lyd_free_tree(match);
     }

     if (lyd_new_opaq2(err, NULL, "error-path", error_path, NULL, NC_NS_BASE, NULL)) {
         return -1;
     }

     return 0;
 }

 API const char *
 nc_err_get_path(const struct lyd_node *err)
 {
     struct lyd_node *match;

     if (!err) {
         ERRARG("err");
         return 0;
     }

     lyd_find_sibling_opaq_next(lyd_child(err), "error-path", &match);
     if (match) {
         return ((struct lyd_node_opaq *)match)->value;
     }

     return NULL;
 }

 API int
 nc_err_set_msg(struct lyd_node *err, const char *error_message, const char *lang)
 {
     struct lyd_node *match;
     struct lyd_attr *attr;

     if (!err) {
         ERRARG("err");
         return -1;
     } else if (!error_message) {
         ERRARG("error_message");
         return -1;
     }

     /* remove previous message */
     lyd_find_sibling_opaq_next(lyd_child(err), "error-message", &match);
     if (match) {
         lyd_free_tree(match);
     }

     if (lyd_new_opaq2(err, NULL, "error-message", error_message, NULL, NC_NS_BASE, &match)) {
         return -1;
     }
     if (lang && lyd_new_attr(match, NULL, "xml:lang", lang, &attr)) {
         lyd_free_tree(match);
         return -1;
     }

     return 0;
 }

 API const char *
 nc_err_get_msg(const struct lyd_node *err)
 {
     struct lyd_node *match;

     if (!err) {
         ERRARG("err");
         return NULL;
     }

     lyd_find_sibling_opaq_next(lyd_child(err), "error-message", &match);
     if (match) {
         return ((struct lyd_node_opaq *)match)->value;
     }

     return NULL;
 }

 API int
 nc_err_set_sid(struct lyd_node *err, uint32_t session_id)
 {
     struct lyd_node *match, *info;
     char buf[22];

     if (!err) {
         ERRARG("err");
         return -1;
     }

     /* find error-info */
     lyd_find_sibling_opaq_next(lyd_child(err), "error-info", &info);
     if (!info && lyd_new_opaq2(err, NULL, "error-info", NULL, NULL, NC_NS_BASE, &info)) {
         return -1;
     }

     /* remove previous node */
     lyd_find_sibling_opaq_next(lyd_child(info), "session-id", &match);
     if (match) {
         lyd_free_tree(match);
     }

     sprintf(buf, "%" PRIu32, session_id);
     if (lyd_new_opaq2(info, NULL, "session-id", buf, NULL, NC_NS_BASE, NULL)) {
         return -1;
     }

     return 0;
 }

 API int
 nc_err_add_bad_attr(struct lyd_node *err, const char *attr_name)
 {
     struct lyd_node *info;

     if (!err) {
         ERRARG("err");
         return -1;
     } else if (!attr_name) {
         ERRARG("attr_name");
         return -1;
     }

     /* find error-info */
     lyd_find_sibling_opaq_next(lyd_child(err), "error-info", &info);
     if (!info && lyd_new_opaq2(err, NULL, "error-info", NULL, NULL, NC_NS_BASE, &info)) {
         return -1;
     }

     if (lyd_new_opaq2(info, NULL, "bad-attribute", attr_name, NULL, NC_NS_BASE, NULL)) {
         return -1;
     }

     return 0;
 }

 API int
 nc_err_add_bad_elem(struct lyd_node *err, const char *elem_name)
 {
     struct lyd_node *info;

     if (!err) {
         ERRARG("err");
         return -1;
     } else if (!elem_name) {
         ERRARG("elem_name");
         return -1;
     }

     /* find error-info */
     lyd_find_sibling_opaq_next(lyd_child(err), "error-info", &info);
     if (!info && lyd_new_opaq2(err, NULL, "error-info", NULL, NULL, NC_NS_BASE, &info)) {
         return -1;
     }

     if (lyd_new_opaq2(info, NULL, "bad-element", elem_name, NULL, NC_NS_BASE, NULL)) {
         return -1;
     }

     return 0;
 }

 API int
 nc_err_add_bad_ns(struct lyd_node *err, const char *ns_name)
 {
     struct lyd_node *info;

     if (!err) {
         ERRARG("err");
         return -1;
     } else if (!ns_name) {
         ERRARG("ns_name");
         return -1;
     }

     /* find error-info */
     lyd_find_sibling_opaq_next(lyd_child(err), "error-info", &info);
     if (!info && lyd_new_opaq2(err, NULL, "error-info", NULL, NULL, NC_NS_BASE, &info)) {
         return -1;
     }

     if (lyd_new_opaq2(info, NULL, "bad-namespace", ns_name, NULL, NC_NS_BASE, NULL)) {
         return -1;
     }

     return 0;
 }

 API int
 nc_err_add_info_other(struct lyd_node *err, struct lyd_node *other)
 {
     struct lyd_node *info;

     if (!err) {
         ERRARG("err");
         return -1;
     } else if (!other) {
         ERRARG("other");
         return -1;
     }

     /* find error-info */
     lyd_find_sibling_opaq_next(lyd_child(err), "error-info", &info);
     if (!info && lyd_new_opaq2(err, NULL, "error-info", NULL, NULL, NC_NS_BASE, &info)) {
         return -1;
     }

     lyd_insert_child(info, other);

     return 0;
 }

 void
 nc_server_rpc_free(struct nc_server_rpc *rpc)
 {
     if (!rpc) {
         return;
     }

     lyd_free_tree(rpc->envp);

     /* may be action */
     lyd_free_all(rpc->rpc);

     free(rpc);
 }

 API void
 nc_server_reply_free(struct nc_server_reply *reply)
 {
     struct nc_server_reply_data *data_rpl;
     struct nc_server_reply_error *error_rpl;

     if (!reply) {
         return;
     }

     switch (reply->type) {
     case NC_RPL_DATA:
         data_rpl = (struct nc_server_reply_data *)reply;
         if (data_rpl->free) {
             lyd_free_siblings(data_rpl->data);
         }
         break;
     case NC_RPL_OK:
         /* nothing to free */
         break;
     case NC_RPL_ERROR:
         error_rpl = (struct nc_server_reply_error *)reply;
         lyd_free_siblings(error_rpl->err);
         break;
     default:
         break;
     }
     free(reply);
 }

 API struct nc_server_notif *
 nc_server_notif_new(struct lyd_node *event, char *eventtime, NC_PARAMTYPE paramtype)
 {
     struct nc_server_notif *ntf;
     struct lyd_node *elem;
     int found;

     if (!event) {
         ERRARG("event");
         return NULL;
     } else if (!eventtime) {
         ERRARG("eventtime");
         return NULL;
     }

     /* check that there is a notification */
     found = 0;
     LYD_TREE_DFS_BEGIN(event, elem) {
         if (elem->schema->nodetype == LYS_NOTIF) {
             found = 1;
             break;
         }
         LYD_TREE_DFS_END(event, elem);
     }
     if (!found) {
         ERRARG("event");
         return NULL;
     }

     ntf = malloc(sizeof *ntf);
     if (!ntf) {
         ERRMEM;
         return NULL;
     }

     if (paramtype == NC_PARAMTYPE_DUP_AND_FREE) {
         ntf->eventtime = strdup(eventtime);
         if (lyd_dup_single(event, NULL, LYD_DUP_RECURSIVE, &ntf->ntf)) {
             free(ntf);
             return NULL;
         }
     } else {
         ntf->eventtime = eventtime;
         ntf->ntf = event;
     }
     ntf->free = (paramtype == NC_PARAMTYPE_CONST ? 0 : 1);

     return ntf;
 }

 API void
 nc_server_notif_free(struct nc_server_notif *notif)
 {
     if (!notif) {
         return;
     }

     if (notif->free) {
         lyd_free_tree(notif->ntf);
         free(notif->eventtime);
     }
     free(notif);
 }

 API const char *
 nc_server_notif_get_time(const struct nc_server_notif *notif)
 {
     if (!notif) {
         ERRARG("notif");
         return NULL;
     }

     return notif->eventtime;
 }
	/**
	* @file messages_server.c
	* @author Michal Vasko <mvasko@cesnet.cz>
	* @brief libnetconf2 - server NETCONF messages functions
	*
	* @copyright
	* Copyright (c) 2015 CESNET, z.s.p.o.
	*
	* This source code is licensed under BSD 3-Clause License (the "License").
	* You may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* https://opensource.org/licenses/BSD-3-Clause
	*/

	#define _GNU_SOURCE /* pthread_rwlock_t, strdup */

	#include <ctype.h>
	#include <inttypes.h>
	#include <stdarg.h>
	#include <stdlib.h>
	#include <string.h>

	#include <libyang/libyang.h>

	#include "compat.h"
	#include "libnetconf.h"
	#include "session_server.h"

	extern struct nc_server_opts server_opts;

	API struct nc_server_reply *
	nc_server_reply_ok(void)
	{
	struct nc_server_reply *ret;

	ret = malloc(sizeof *ret);
	if (!ret) {
	ERRMEM;
	return NULL;
	}

	ret->type = NC_RPL_OK;
	return ret;
	}

	API struct nc_server_reply *
	nc_server_reply_data(struct lyd_node *data, NC_WD_MODE wd, NC_PARAMTYPE paramtype)
	{
	struct nc_server_reply_data *ret;

	if (!data \|\| !(data->schema->nodetype & (LYS_RPC \| LYS_ACTION))) {
	ERRARG("data");
	return NULL;
	}

	ret = malloc(sizeof *ret);
	if (!ret) {
	ERRMEM;
	return NULL;
	}

	ret->type = NC_RPL_DATA;
	ret->wd = wd;
	if (paramtype == NC_PARAMTYPE_DUP_AND_FREE) {
	if (lyd_dup_single(data, NULL, LYD_DUP_RECURSIVE, &ret->data)) {
	free(ret);
	return NULL;
	}
	} else {
	ret->data = data;
	}
	if (paramtype != NC_PARAMTYPE_CONST) {
	ret->free = 1;
	} else {
	ret->free = 0;
	}
	return (struct nc_server_reply *)ret;
	}

	API struct nc_server_reply *
	nc_server_reply_err(struct lyd_node *err)
	{
	struct nc_server_reply_error *ret;

	if (!err) {
	ERRARG("err");
	return NULL;
	}

	ret = malloc(sizeof *ret);
	if (!ret) {
	ERRMEM;
	return NULL;
	}

	ret->type = NC_RPL_ERROR;
	ret->err = err;
	return (struct nc_server_reply *)ret;
	}

	API int
	nc_server_reply_add_err(struct nc_server_reply reply, struct lyd_node err)
	{
	struct nc_server_reply_error *err_rpl;

	if (!reply \|\| (reply->type != NC_RPL_ERROR)) {
	ERRARG("reply");
	return -1;
	} else if (!err) {
	ERRARG("err");
	return -1;
	}

	err_rpl = (struct nc_server_reply_error *)reply;
	lyd_insert_sibling(err_rpl->err, err, &err_rpl->err);
	return 0;
	}

	API const struct lyd_node *
	nc_server_reply_get_last_err(const struct nc_server_reply *reply)
	{
	struct nc_server_reply_error *err_rpl;

	if (!reply \|\| (reply->type != NC_RPL_ERROR)) {
	ERRARG("reply");
	return NULL;
	}

	err_rpl = (struct nc_server_reply_error *)reply;
	if (!err_rpl->err) {
	return NULL;
	}
	return err_rpl->err->prev;
	}

	static const char *
	nc_err_tag2str(NC_ERR tag)
	{
	switch (tag) {
	case NC_ERR_IN_USE:
	return "in-use";
	case NC_ERR_INVALID_VALUE:
	return "invalid-value";
	case NC_ERR_ACCESS_DENIED:
	return "access-denied";
	case NC_ERR_ROLLBACK_FAILED:
	return "rollback-failed";
	case NC_ERR_OP_NOT_SUPPORTED:
	return "operation-not-supported";
	case NC_ERR_TOO_BIG:
	return "too-big";
	case NC_ERR_RES_DENIED:
	return "resource-denied";
	case NC_ERR_MISSING_ATTR:
	return "missing-attribute";
	case NC_ERR_BAD_ATTR:
	return "bad-attribute";
	case NC_ERR_UNKNOWN_ATTR:
	return "unknown-attribute";
	case NC_ERR_MISSING_ELEM:
	return "missing-element";
	case NC_ERR_BAD_ELEM:
	return "bad-element";
	case NC_ERR_UNKNOWN_ELEM:
	return "unknown-element";
	case NC_ERR_UNKNOWN_NS:
	return "unknown-namespace";
	case NC_ERR_LOCK_DENIED:
	return "lock-denied";
	case NC_ERR_DATA_EXISTS:
	return "data-exists";
	case NC_ERR_DATA_MISSING:
	return "data-missing";
	case NC_ERR_OP_FAILED:
	return "operation-failed";
	case NC_ERR_MALFORMED_MSG:
	return "malformed-message";
	default:
	break;
	}

	return NULL;
	}

	static NC_ERR
	nc_err_str2tag(const char *str)
	{
	if (!strcmp(str, "in-use")) {
	return NC_ERR_IN_USE;
	} else if (!strcmp(str, "invalid-value")) {
	return NC_ERR_INVALID_VALUE;
	} else if (!strcmp(str, "access-denied")) {
	return NC_ERR_ACCESS_DENIED;
	} else if (!strcmp(str, "rollback-failed")) {
	return NC_ERR_ROLLBACK_FAILED;
	} else if (!strcmp(str, "operation-not-supported")) {
	return NC_ERR_OP_NOT_SUPPORTED;
	} else if (!strcmp(str, "too-big")) {
	return NC_ERR_TOO_BIG;
	} else if (!strcmp(str, "resource-denied")) {
	return NC_ERR_RES_DENIED;
	} else if (!strcmp(str, "missing-attribute")) {
	return NC_ERR_MISSING_ATTR;
	} else if (!strcmp(str, "bad-attribute")) {
	return NC_ERR_BAD_ATTR;
	} else if (!strcmp(str, "unknown-attribute")) {
	return NC_ERR_UNKNOWN_ATTR;
	} else if (!strcmp(str, "missing-element")) {
	return NC_ERR_MISSING_ELEM;
	} else if (!strcmp(str, "bad-element")) {
	return NC_ERR_BAD_ELEM;
	} else if (!strcmp(str, "unknown-element")) {
	return NC_ERR_UNKNOWN_ELEM;
	} else if (!strcmp(str, "unknown-namespace")) {
	return NC_ERR_UNKNOWN_NS;
	} else if (!strcmp(str, "lock-denied")) {
	return NC_ERR_LOCK_DENIED;
	} else if (!strcmp(str, "data-exists")) {
	return NC_ERR_DATA_EXISTS;
	} else if (!strcmp(str, "data-missing")) {
	return NC_ERR_DATA_MISSING;
	} else if (!strcmp(str, "operation-failed")) {
	return NC_ERR_OP_FAILED;
	} else if (!strcmp(str, "malformed-message")) {
	return NC_ERR_MALFORMED_MSG;
	}

	return 0;
	}

	static const char *
	nc_err_type2str(NC_ERR_TYPE type)
	{
	switch (type) {
	case NC_ERR_TYPE_TRAN:
	return "transport";
	case NC_ERR_TYPE_RPC:
	return "rpc";
	case NC_ERR_TYPE_PROT:
	return "protocol";
	case NC_ERR_TYPE_APP:
	return "application";
	default:
	break;
	}

	return NULL;
	}

	static NC_ERR_TYPE
	nc_err_str2type(const char *str)
	{
	if (!strcmp(str, "transport")) {
	return NC_ERR_TYPE_TRAN;
	} else if (!strcmp(str, "rpc")) {
	return NC_ERR_TYPE_RPC;
	} else if (!strcmp(str, "protocol")) {
	return NC_ERR_TYPE_PROT;
	} else if (!strcmp(str, "application")) {
	return NC_ERR_TYPE_APP;
	}

	return 0;
	}

	API struct lyd_node *
	nc_err(const struct ly_ctx *ctx, NC_ERR tag, ...)
	{
	va_list ap;
	struct lyd_node *err = NULL;
	NC_ERR_TYPE type;
	const char arg1, arg2;
	uint32_t sid;

	if (!tag) {
	ERRARG("tag");
	return NULL;
	}

	/* rpc-error */
	if (lyd_new_opaq2(NULL, ctx, "rpc-error", NULL, NULL, NC_NS_BASE, &err)) {
	return NULL;
	}

	va_start(ap, tag);

	/* error-type */
	switch (tag) {
	case NC_ERR_IN_USE:
	case NC_ERR_INVALID_VALUE:
	case NC_ERR_ACCESS_DENIED:
	case NC_ERR_ROLLBACK_FAILED:
	case NC_ERR_OP_NOT_SUPPORTED:
	type = (NC_ERR_TYPE)va_arg(ap, int); /* NC_ERR_TYPE enum is automatically promoted to int */
	if ((type != NC_ERR_TYPE_PROT) && (type != NC_ERR_TYPE_APP)) {
	ERRARG("type");
	goto fail;
	}
	break;
	case NC_ERR_TOO_BIG:
	case NC_ERR_RES_DENIED:
	type = (NC_ERR_TYPE)va_arg(ap, int);
	break;
	case NC_ERR_MISSING_ATTR:
	case NC_ERR_BAD_ATTR:
	case NC_ERR_UNKNOWN_ATTR:
	type = (NC_ERR_TYPE)va_arg(ap, int);
	if (type == NC_ERR_TYPE_TRAN) {
	ERRARG("type");
	goto fail;
	}
	break;
	case NC_ERR_MISSING_ELEM:
	case NC_ERR_BAD_ELEM:
	case NC_ERR_UNKNOWN_ELEM:
	type = (NC_ERR_TYPE)va_arg(ap, int);
	if ((type != NC_ERR_TYPE_PROT) && (type != NC_ERR_TYPE_APP)) {
	ERRARG("type");
	goto fail;
	}
	break;
	case NC_ERR_UNKNOWN_NS:
	type = (NC_ERR_TYPE)va_arg(ap, int);
	if ((type != NC_ERR_TYPE_PROT) && (type != NC_ERR_TYPE_APP)) {
	ERRARG("type");
	goto fail;
	}
	break;
	case NC_ERR_LOCK_DENIED:
	type = NC_ERR_TYPE_PROT;
	break;
	case NC_ERR_DATA_EXISTS:
	case NC_ERR_DATA_MISSING:
	type = NC_ERR_TYPE_APP;
	break;
	case NC_ERR_OP_FAILED:
	type = (NC_ERR_TYPE)va_arg(ap, int);
	if (type == NC_ERR_TYPE_TRAN) {
	ERRARG("type");
	goto fail;
	}
	break;
	case NC_ERR_MALFORMED_MSG:
	type = NC_ERR_TYPE_RPC;
	break;
	default:
	ERRARG("tag");
	goto fail;
	}
	if (lyd_new_opaq2(err, NULL, "error-type", nc_err_type2str(type), NULL, NC_NS_BASE, NULL)) {
	goto fail;
	}

	/* error-tag */
	if (lyd_new_opaq2(err, NULL, "error-tag", nc_err_tag2str(tag), NULL, NC_NS_BASE, NULL)) {
	goto fail;
	}

	/* error-severity */
	if (lyd_new_opaq2(err, NULL, "error-severity", "error", NULL, NC_NS_BASE, NULL)) {
	goto fail;
	}

	/* error-message */
	switch (tag) {
	case NC_ERR_IN_USE:
	nc_err_set_msg(err, "The request requires a resource that already is in use.", "en");
	break;
	case NC_ERR_INVALID_VALUE:
	nc_err_set_msg(err, "The request specifies an unacceptable value for one or more parameters.", "en");
	break;
	case NC_ERR_TOO_BIG:
	nc_err_set_msg(err, "The request or response (that would be generated) is too large for the implementation to handle.", "en");
	break;
	case NC_ERR_MISSING_ATTR:
	nc_err_set_msg(err, "An expected attribute is missing.", "en");
	break;
	case NC_ERR_BAD_ATTR:
	nc_err_set_msg(err, "An attribute value is not correct.", "en");
	break;
	case NC_ERR_UNKNOWN_ATTR:
	nc_err_set_msg(err, "An unexpected attribute is present.", "en");
	break;
	case NC_ERR_MISSING_ELEM:
	nc_err_set_msg(err, "An expected element is missing.", "en");
	break;
	case NC_ERR_BAD_ELEM:
	nc_err_set_msg(err, "An element value is not correct.", "en");
	break;
	case NC_ERR_UNKNOWN_ELEM:
	nc_err_set_msg(err, "An unexpected element is present.", "en");
	break;
	case NC_ERR_UNKNOWN_NS:
	nc_err_set_msg(err, "An unexpected namespace is present.", "en");
	break;
	case NC_ERR_ACCESS_DENIED:
	nc_err_set_msg(err, "Access to the requested protocol operation or data model is denied because authorization failed.", "en");
	break;
	case NC_ERR_LOCK_DENIED:
	nc_err_set_msg(err, "Access to the requested lock is denied because the lock is currently held by another entity.", "en");
	break;
	case NC_ERR_RES_DENIED:
	nc_err_set_msg(err, "Request could not be completed because of insufficient resources.", "en");
	break;
	case NC_ERR_ROLLBACK_FAILED:
	nc_err_set_msg(err, "Request to roll back some configuration change was not completed for some reason.", "en");
	break;
	case NC_ERR_DATA_EXISTS:
	nc_err_set_msg(err, "Request could not be completed because the relevant data model content already exists.", "en");
	break;
	case NC_ERR_DATA_MISSING:
	nc_err_set_msg(err, "Request could not be completed because the relevant data model content does not exist.", "en");
	break;
	case NC_ERR_OP_NOT_SUPPORTED:
	nc_err_set_msg(err, "Request could not be completed because the requested operation is not supported by this implementation.", "en");
	break;
	case NC_ERR_OP_FAILED:
	nc_err_set_msg(err, "Request could not be completed because the requested operation failed for a non-specific reason.", "en");
	break;
	case NC_ERR_MALFORMED_MSG:
	nc_err_set_msg(err, "A message could not be handled because it failed to be parsed correctly.", "en");
	break;
	default:
	ERRARG("tag");
	goto fail;
	}

	/* error-info */
	switch (tag) {
	case NC_ERR_IN_USE:
	case NC_ERR_INVALID_VALUE:
	case NC_ERR_ACCESS_DENIED:
	case NC_ERR_ROLLBACK_FAILED:
	case NC_ERR_OP_NOT_SUPPORTED:
	case NC_ERR_TOO_BIG:
	case NC_ERR_RES_DENIED:
	case NC_ERR_DATA_EXISTS:
	case NC_ERR_DATA_MISSING:
	case NC_ERR_OP_FAILED:
	case NC_ERR_MALFORMED_MSG:
	break;
	case NC_ERR_MISSING_ATTR:
	case NC_ERR_BAD_ATTR:
	case NC_ERR_UNKNOWN_ATTR:
	arg1 = va_arg(ap, const char *);
	arg2 = va_arg(ap, const char *);

	nc_err_add_bad_attr(err, arg1);
	nc_err_add_bad_elem(err, arg2);
	break;
	case NC_ERR_MISSING_ELEM:
	case NC_ERR_BAD_ELEM:
	case NC_ERR_UNKNOWN_ELEM:
	arg1 = va_arg(ap, const char *);

	nc_err_add_bad_elem(err, arg1);
	break;
	case NC_ERR_UNKNOWN_NS:
	arg1 = va_arg(ap, const char *);
	arg2 = va_arg(ap, const char *);

	nc_err_add_bad_elem(err, arg1);
	nc_err_add_bad_ns(err, arg2);
	break;
	case NC_ERR_LOCK_DENIED:
	sid = va_arg(ap, uint32_t);

	nc_err_set_sid(err, sid);
	break;
	default:
	ERRARG("tag");
	goto fail;
	}

	va_end(ap);
	return err;

	fail:
	va_end(ap);
	lyd_free_siblings(err);
	return NULL;
	}

	API NC_ERR_TYPE
	nc_err_get_type(const struct lyd_node *err)
	{
	struct lyd_node *match;

	if (!err) {
	ERRARG("err");
	return 0;
	}

	lyd_find_sibling_opaq_next(lyd_child(err), "error-type", &match);
	if (match) {
	return nc_err_str2type(((struct lyd_node_opaq *)match)->value);
	}

	return 0;
	}

	API NC_ERR
	nc_err_get_tag(const struct lyd_node *err)
	{
	struct lyd_node *match;

	if (!err) {
	ERRARG("err");
	return 0;
	}

	lyd_find_sibling_opaq_next(lyd_child(err), "error-tag", &match);
	if (match) {
	return nc_err_str2tag(((struct lyd_node_opaq *)match)->value);
	}

	return 0;
	}

	API int
	nc_err_set_app_tag(struct lyd_node err, const char error_app_tag)
	{
	struct lyd_node *match;

	if (!err) {
	ERRARG("err");
	return -1;
	} else if (!error_app_tag) {
	ERRARG("error_app_tag");
	return -1;
	}

	/* remove previous node */
	lyd_find_sibling_opaq_next(lyd_child(err), "error-app-tag", &match);
	if (match) {
	lyd_free_tree(match);
	}

	if (lyd_new_opaq2(err, NULL, "error-app-tag", error_app_tag, NULL, NC_NS_BASE, NULL)) {
	return -1;
	}

	return 0;
	}

	API const char *
	nc_err_get_app_tag(const struct lyd_node *err)
	{
	struct lyd_node *match;

	if (!err) {
	ERRARG("err");
	return NULL;
	}

	lyd_find_sibling_opaq_next(lyd_child(err), "error-app-tag", &match);
	if (match) {
	return ((struct lyd_node_opaq *)match)->value;
	}

	return NULL;
	}

	API int
	nc_err_set_path(struct lyd_node err, const char error_path)
	{
	struct lyd_node *match;

	if (!err) {
	ERRARG("err");
	return -1;
	} else if (!error_path) {
	ERRARG("error_path");
	return -1;
	}

	/* remove previous node */
	lyd_find_sibling_opaq_next(lyd_child(err), "error-path", &match);
	if (match) {
	lyd_free_tree(match);
	}

	if (lyd_new_opaq2(err, NULL, "error-path", error_path, NULL, NC_NS_BASE, NULL)) {
	return -1;
	}

	return 0;
	}

	API const char *
	nc_err_get_path(const struct lyd_node *err)
	{
	struct lyd_node *match;

	if (!err) {
	ERRARG("err");
	return 0;
	}

	lyd_find_sibling_opaq_next(lyd_child(err), "error-path", &match);
	if (match) {
	return ((struct lyd_node_opaq *)match)->value;
	}

	return NULL;
	}

	API int
	nc_err_set_msg(struct lyd_node err, const char error_message, const char *lang)
	{
	struct lyd_node *match;
	struct lyd_attr *attr;

	if (!err) {
	ERRARG("err");
	return -1;
	} else if (!error_message) {
	ERRARG("error_message");
	return -1;
	}

	/* remove previous message */
	lyd_find_sibling_opaq_next(lyd_child(err), "error-message", &match);
	if (match) {
	lyd_free_tree(match);
	}

	if (lyd_new_opaq2(err, NULL, "error-message", error_message, NULL, NC_NS_BASE, &match)) {
	return -1;
	}
	if (lang && lyd_new_attr(match, NULL, "xml:lang", lang, &attr)) {
	lyd_free_tree(match);
	return -1;
	}

	return 0;
	}

	API const char *
	nc_err_get_msg(const struct lyd_node *err)
	{
	struct lyd_node *match;

	if (!err) {
	ERRARG("err");
	return NULL;
	}

	lyd_find_sibling_opaq_next(lyd_child(err), "error-message", &match);
	if (match) {
	return ((struct lyd_node_opaq *)match)->value;
	}

	return NULL;
	}

	API int
	nc_err_set_sid(struct lyd_node *err, uint32_t session_id)
	{
	struct lyd_node match, info;
	char buf[22];

	if (!err) {
	ERRARG("err");
	return -1;
	}

	/* find error-info */
	lyd_find_sibling_opaq_next(lyd_child(err), "error-info", &info);
	if (!info && lyd_new_opaq2(err, NULL, "error-info", NULL, NULL, NC_NS_BASE, &info)) {
	return -1;
	}

	/* remove previous node */
	lyd_find_sibling_opaq_next(lyd_child(info), "session-id", &match);
	if (match) {
	lyd_free_tree(match);
	}

	sprintf(buf, "%" PRIu32, session_id);
	if (lyd_new_opaq2(info, NULL, "session-id", buf, NULL, NC_NS_BASE, NULL)) {
	return -1;
	}

	return 0;
	}

	API int
	nc_err_add_bad_attr(struct lyd_node err, const char attr_name)
	{
	struct lyd_node *info;

	if (!err) {
	ERRARG("err");
	return -1;
	} else if (!attr_name) {
	ERRARG("attr_name");
	return -1;
	}

	/* find error-info */
	lyd_find_sibling_opaq_next(lyd_child(err), "error-info", &info);
	if (!info && lyd_new_opaq2(err, NULL, "error-info", NULL, NULL, NC_NS_BASE, &info)) {
	return -1;
	}

	if (lyd_new_opaq2(info, NULL, "bad-attribute", attr_name, NULL, NC_NS_BASE, NULL)) {
	return -1;
	}

	return 0;
	}

	API int
	nc_err_add_bad_elem(struct lyd_node err, const char elem_name)
	{
	struct lyd_node *info;

	if (!err) {
	ERRARG("err");
	return -1;
	} else if (!elem_name) {
	ERRARG("elem_name");
	return -1;
	}

	/* find error-info */
	lyd_find_sibling_opaq_next(lyd_child(err), "error-info", &info);
	if (!info && lyd_new_opaq2(err, NULL, "error-info", NULL, NULL, NC_NS_BASE, &info)) {
	return -1;
	}

	if (lyd_new_opaq2(info, NULL, "bad-element", elem_name, NULL, NC_NS_BASE, NULL)) {
	return -1;
	}

	return 0;
	}

	API int
	nc_err_add_bad_ns(struct lyd_node err, const char ns_name)
	{
	struct lyd_node *info;

	if (!err) {
	ERRARG("err");
	return -1;
	} else if (!ns_name) {
	ERRARG("ns_name");
	return -1;
	}

	/* find error-info */
	lyd_find_sibling_opaq_next(lyd_child(err), "error-info", &info);
	if (!info && lyd_new_opaq2(err, NULL, "error-info", NULL, NULL, NC_NS_BASE, &info)) {
	return -1;
	}

	if (lyd_new_opaq2(info, NULL, "bad-namespace", ns_name, NULL, NC_NS_BASE, NULL)) {
	return -1;
	}

	return 0;
	}

	API int
	nc_err_add_info_other(struct lyd_node err, struct lyd_node other)
	{
	struct lyd_node *info;

	if (!err) {
	ERRARG("err");
	return -1;
	} else if (!other) {
	ERRARG("other");
	return -1;
	}

	/* find error-info */
	lyd_find_sibling_opaq_next(lyd_child(err), "error-info", &info);
	if (!info && lyd_new_opaq2(err, NULL, "error-info", NULL, NULL, NC_NS_BASE, &info)) {
	return -1;
	}

	lyd_insert_child(info, other);

	return 0;
	}

	void
	nc_server_rpc_free(struct nc_server_rpc *rpc)
	{
	if (!rpc) {
	return;
	}

	lyd_free_tree(rpc->envp);

	/* may be action */
	lyd_free_all(rpc->rpc);

	free(rpc);
	}

	API void
	nc_server_reply_free(struct nc_server_reply *reply)
	{
	struct nc_server_reply_data *data_rpl;
	struct nc_server_reply_error *error_rpl;

	if (!reply) {
	return;
	}

	switch (reply->type) {
	case NC_RPL_DATA:
	data_rpl = (struct nc_server_reply_data *)reply;
	if (data_rpl->free) {
	lyd_free_siblings(data_rpl->data);
	}
	break;
	case NC_RPL_OK:
	/* nothing to free */
	break;
	case NC_RPL_ERROR:
	error_rpl = (struct nc_server_reply_error *)reply;
	lyd_free_siblings(error_rpl->err);
	break;
	default:
	break;
	}
	free(reply);
	}

	API struct nc_server_notif *
	nc_server_notif_new(struct lyd_node event, char eventtime, NC_PARAMTYPE paramtype)
	{
	struct nc_server_notif *ntf;
	struct lyd_node *elem;
	int found;

	if (!event) {
	ERRARG("event");
	return NULL;
	} else if (!eventtime) {
	ERRARG("eventtime");
	return NULL;
	}

	/* check that there is a notification */
	found = 0;
	LYD_TREE_DFS_BEGIN(event, elem) {
	if (elem->schema->nodetype == LYS_NOTIF) {
	found = 1;
	break;
	}
	LYD_TREE_DFS_END(event, elem);
	}
	if (!found) {
	ERRARG("event");
	return NULL;
	}

	ntf = malloc(sizeof *ntf);
	if (!ntf) {
	ERRMEM;
	return NULL;
	}

	if (paramtype == NC_PARAMTYPE_DUP_AND_FREE) {
	ntf->eventtime = strdup(eventtime);
	if (lyd_dup_single(event, NULL, LYD_DUP_RECURSIVE, &ntf->ntf)) {
	free(ntf);
	return NULL;
	}
	} else {
	ntf->eventtime = eventtime;
	ntf->ntf = event;
	}
	ntf->free = (paramtype == NC_PARAMTYPE_CONST ? 0 : 1);

	return ntf;
	}

	API void
	nc_server_notif_free(struct nc_server_notif *notif)
	{
	if (!notif) {
	return;
	}

	if (notif->free) {
	lyd_free_tree(notif->ntf);
	free(notif->eventtime);
	}
	free(notif);
	}

	API const char *
	nc_server_notif_get_time(const struct nc_server_notif *notif)
	{
	if (!notif) {
	ERRARG("notif");
	return NULL;
	}

	return notif->eventtime;
	}