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/**
* @file libyang.h
* @author Radek Krejci <rkrejci@cesnet.cz>
* @author Michal Vasko <mvasko@cesnet.cz>
* @brief The main libyang public header.
*
* Copyright (c) 2015 - 2025 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
*/
#ifndef LY_LIBYANG_H_
#define LY_LIBYANG_H_
#include <stdint.h>
#ifdef __cplusplus
extern "C" {
#endif
#include "ly_config.h"
#include "context.h"
#include "dict.h"
#include "in.h"
#include "log.h"
#include "metadata.h"
#include "out.h"
#include "parser_data.h"
#include "parser_schema.h"
#include "printer_data.h"
#include "printer_schema.h"
#include "set.h"
#include "tree.h"
#include "tree_data.h"
#include "tree_schema.h"
/**
* @brief libyang v3 compatibility macros with v2.
*/
#define ly_strerrcode ly_strerr
#define ly_last_errmsg ly_last_logmsg
#define ly_errcode(ctx) (ly_err_last(ctx) ? ly_err_last(ctx)->err : 0)
#define ly_errmsg(ctx) (ly_err_last(ctx) ? ly_err_last(ctx)->msg : NULL)
#define ly_errpath(ctx) (ly_err_last(ctx) ? (ly_err_last(ctx)->data_path ? ly_err_last(ctx)->data_path : ly_err_last(ctx)->schema_path) : NULL)
#define ly_vecode(ctx) (ly_err_last(ctx) ? ly_err_last(ctx)->vecode : 0)
/*
* The following headers are supposed to be included explicitly:
* - hash_table.h
* - metadata.h
* - plugins_types.h
* - plugins_exts.h
*/
/**
* @mainpage About
*
* libyang is a library implementing processing of the YANG schemas and data modeled by the YANG language. The
* library is implemented in C for GNU/Linux and provides C API.
*
* @section about-features Main Features
*
* - [Parsing (and validating) schemas](@ref howtoSchema) in YANG format.
* - [Parsing (and validating) schemas](@ref howtoSchema) in YIN format.
* - [Parsing, validating and printing instance data](@ref howtoData) in XML format.
* - [Parsing, validating and printing instance data](@ref howtoData) in JSON format
* ([RFC 7951](https://tools.ietf.org/html/rfc7951)).
* - [Manipulation with the instance data](@ref howtoDataManipulation).
* - Support for [default values in the instance data](@ref howtoDataWD) ([RFC 6243](https://tools.ietf.org/html/rfc6243)).
* - Support for [YANG extensions and user types](@ref howtoPlugins).
* - Support for [YANG Metadata](@ref howtoDataMetadata) ([RFC 7952](https://tools.ietf.org/html/rfc6243)).
* - Support for [YANG Schema Mount](@ref howtoDataMountpoint) ([RFC 8528](https://tools.ietf.org/html/rfc8528)).
*
* The current implementation covers YANG 1.0 ([RFC 6020](https://tools.ietf.org/html/rfc6020)) as well as
* YANG 1.1 ([RFC 7950](https://tools.ietf.org/html/rfc7950)).
*
* @section about-license License
*
* Copyright (c) 2015 - 2025 CESNET, z.s.p.o.
*
* (The BSD 3-Clause License)
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name of the Company nor the names of its contributors
* may be used to endorse or promote products derived from this
* software without specific prior written permission.
*/
/**
* @page howto libyang API Overview
*
* @section howtoGeneral General notes
*
* libyang is primarily intended for handling data modeled by YANG modeling language, so the library is supposed to be optimized
* for this purpose. However, as a side effect, the library has to be able precisely process YANG modules. Thus, it is usable by
* YANG module authors to validate their modules and schemas in the development process.
*
* - @subpage howtoStructures
* - @subpage howtoErrors
* - @subpage howtoLogger
* - @subpage howtoThreads
* - @subpage howtoContext
* - @subpage howtoInput
* - @subpage howtoOutput
* - @subpage howtoSchema
* - @subpage howtoData
* - @subpage howtoXPath
* - @subpage howtoPlugins
*/
/**
* @page howtoStructures Data Structures
*
* @section sizedarrays Sized Arrays
*
* The structure starts with 32bit number storing size of the array - the number of the items inside. The size is part of the
* array to have it allocated together with the array itself only when it is needed. However, the pointers to the array always
* points after the 32b number, so items can be accessed directly as for standard C arrays. Because of a known size (available
* via ::LY_ARRAY_COUNT macro), it is not terminated by any special byte (sequence), so there is also no limitation for specific
* content of the stored records (e.g. that first byte must not be NULL).
*
* The sized arrays must be carefully freed (which should be done anyway only internally), since pointers to the sized arrays used
* in libyang structures, does not point to the beginning of the allocated space.
*
* - ::LY_ARRAY_COUNT
* - ::LY_ARRAY_FOR
*
* @section struct_lists Lists
*
* The lists are structures connected via a `next` and `prev` pointers. Iterating over the siblings can be simply done by
* ::LY_LIST_FOR macro. Examples of such structures are ::lyd_node or ::lysc_node.
*
* The `prev` pointer is always filled. In case there is just a single item in the list, the `prev` pointer points to the
* item itself. Otherwise, the `prev` pointer of the first item points to the last item of the list. In contrast, the
* `next` pointer of the last item in the list is always NULL.
*/
/**
* @page howtoThreads Threading Limitations
*
* @section context Context
*
* It is safe to read from ::ly_ctx structure concurrently and use its dictionary, which is protected by a lock.
* Thread-safe functions include any ones working with data trees (only context dictionary is accessed) and all
* the `ly_ctx_get_*()` functions. Generally, they are the functions with `const` context parameter.
*
* @section data Data Trees
*
* Data trees are not internally synchronized so the general safe practice of a single writer **or** several concurrent
* readers should be followed. Specifically, only the functions with non-const ::lyd_node parameters modify the node(s)
* and no concurrent execution of such functions should be allowed on a single data tree or subtrees of one.
*/
/**
* @internal
* @page internals Developers' Notes
* @tableofcontents
*
* Following texts describes various internal subsystems and mechanism in libyang which are hidden from external users, but important
* for libyang developers. The texts should explain various decisions made and internal processes utilized in libyang.
*/
#ifdef __cplusplus
}
#endif
#endif /* LY_LIBYANG_H_ */