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+/* Copyright (c) 2013-2015, Vsevolod Stakhov
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED ''AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL AUTHOR BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef UCL_H_
+#define UCL_H_
+
+#include <string.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdarg.h>
+#include <stdio.h>
+
+#ifdef _WIN32
+# define UCL_EXTERN __declspec(dllexport)
+#else
+# define UCL_EXTERN
+#endif
+
+/**
+ * @mainpage
+ * This is a reference manual for UCL API. You may find the description of UCL format by following this
+ * [github repository](https://github.com/vstakhov/libucl).
+ *
+ * This manual has several main sections:
+ * - @ref structures
+ * - @ref utils
+ * - @ref parser
+ * - @ref emitter
+ */
+
+/**
+ * @file ucl.h
+ * @brief UCL parsing and emitting functions
+ *
+ * UCL is universal configuration language, which is a form of
+ * JSON with less strict rules that make it more comfortable for
+ * using as a configuration language
+ */
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*
+ * Memory allocation utilities
+ * UCL_ALLOC(size) - allocate memory for UCL
+ * UCL_FREE(size, ptr) - free memory of specified size at ptr
+ * Default: malloc and free
+ */
+#ifndef UCL_ALLOC
+#define UCL_ALLOC(size) malloc(size)
+#endif
+#ifndef UCL_FREE
+#define UCL_FREE(size, ptr) free(ptr)
+#endif
+
+#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
+#define UCL_WARN_UNUSED_RESULT \
+ __attribute__((warn_unused_result))
+#else
+#define UCL_WARN_UNUSED_RESULT
+#endif
+
+#ifdef __GNUC__
+#define UCL_DEPRECATED(func) func __attribute__ ((deprecated))
+#elif defined(_MSC_VER)
+#define UCL_DEPRECATED(func) __declspec(deprecated) func
+#else
+#define UCL_DEPRECATED(func) func
+#endif
+
+/**
+ * @defgroup structures Structures and types
+ * UCL defines several enumeration types used for error reporting or specifying flags and attributes.
+ *
+ * @{
+ */
+
+/**
+ * The common error codes returned by ucl parser
+ */
+typedef enum ucl_error {
+ UCL_EOK = 0, /**< No error */
+ UCL_ESYNTAX, /**< Syntax error occurred during parsing */
+ UCL_EIO, /**< IO error occurred during parsing */
+ UCL_ESTATE, /**< Invalid state machine state */
+ UCL_ENESTED, /**< Input has too many recursion levels */
+ UCL_EUNPAIRED, /**< Input has too many recursion levels */
+ UCL_EMACRO, /**< Error processing a macro */
+ UCL_EINTERNAL, /**< Internal unclassified error */
+ UCL_ESSL, /**< SSL error */
+ UCL_EMERGE /**< A merge error occurred */
+} ucl_error_t;
+
+/**
+ * #ucl_object_t may have one of specified types, some types are compatible with each other and some are not.
+ * For example, you can always convert #UCL_TIME to #UCL_FLOAT. Also you can convert #UCL_FLOAT to #UCL_INTEGER
+ * by loosing floating point. Every object may be converted to a string by #ucl_object_tostring_forced() function.
+ *
+ */
+typedef enum ucl_type {
+ UCL_OBJECT = 0, /**< UCL object - key/value pairs */
+ UCL_ARRAY, /**< UCL array */
+ UCL_INT, /**< Integer number */
+ UCL_FLOAT, /**< Floating point number */
+ UCL_STRING, /**< Null terminated string */
+ UCL_BOOLEAN, /**< Boolean value */
+ UCL_TIME, /**< Time value (floating point number of seconds) */
+ UCL_USERDATA, /**< Opaque userdata pointer (may be used in macros) */
+ UCL_NULL /**< Null value */
+} ucl_type_t;
+
+/**
+ * You can use one of these types to serialise #ucl_object_t by using ucl_object_emit().
+ */
+typedef enum ucl_emitter {
+ UCL_EMIT_JSON = 0, /**< Emit fine formatted JSON */
+ UCL_EMIT_JSON_COMPACT, /**< Emit compacted JSON */
+ UCL_EMIT_CONFIG, /**< Emit human readable config format */
+ UCL_EMIT_YAML, /**< Emit embedded YAML format */
+ UCL_EMIT_MSGPACK, /**< Emit msgpack output */
+ UCL_EMIT_MAX /**< Unsupported emitter type */
+} ucl_emitter_t;
+
+/**
+ * These flags defines parser behaviour. If you specify #UCL_PARSER_ZEROCOPY you must ensure
+ * that the input memory is not freed if an object is in use. Moreover, if you want to use
+ * zero-terminated keys and string values then you should not use zero-copy mode, as in this case
+ * UCL still has to perform copying implicitly.
+ */
+typedef enum ucl_parser_flags {
+ UCL_PARSER_DEFAULT = 0, /**< No special flags */
+ UCL_PARSER_KEY_LOWERCASE = (1 << 0), /**< Convert all keys to lower case */
+ UCL_PARSER_ZEROCOPY = (1 << 1), /**< Parse input in zero-copy mode if possible */
+ UCL_PARSER_NO_TIME = (1 << 2), /**< Do not parse time and treat time values as strings */
+ UCL_PARSER_NO_IMPLICIT_ARRAYS = (1 << 3), /** Create explicit arrays instead of implicit ones */
+ UCL_PARSER_SAVE_COMMENTS = (1 << 4), /** Save comments in the parser context */
+ UCL_PARSER_DISABLE_MACRO = (1 << 5), /** Treat macros as comments */
+ UCL_PARSER_NO_FILEVARS = (1 << 6) /** Do not set file vars */
+} ucl_parser_flags_t;
+
+/**
+ * String conversion flags, that are used in #ucl_object_fromstring_common function.
+ */
+typedef enum ucl_string_flags {
+ UCL_STRING_RAW = 0x0, /**< Treat string as is */
+ UCL_STRING_ESCAPE = (1 << 0), /**< Perform JSON escape */
+ UCL_STRING_TRIM = (1 << 1), /**< Trim leading and trailing whitespaces */
+ UCL_STRING_PARSE_BOOLEAN = (1 << 2), /**< Parse passed string and detect boolean */
+ UCL_STRING_PARSE_INT = (1 << 3), /**< Parse passed string and detect integer number */
+ UCL_STRING_PARSE_DOUBLE = (1 << 4), /**< Parse passed string and detect integer or float number */
+ UCL_STRING_PARSE_TIME = (1 << 5), /**< Parse time strings */
+ UCL_STRING_PARSE_NUMBER = UCL_STRING_PARSE_INT|UCL_STRING_PARSE_DOUBLE|UCL_STRING_PARSE_TIME, /**<
+ Parse passed string and detect number */
+ UCL_STRING_PARSE = UCL_STRING_PARSE_BOOLEAN|UCL_STRING_PARSE_NUMBER, /**<
+ Parse passed string (and detect booleans and numbers) */
+ UCL_STRING_PARSE_BYTES = (1 << 6) /**< Treat numbers as bytes */
+} ucl_string_flags_t;
+
+/**
+ * Basic flags for an object (can use up to 12 bits as higher 4 bits are used
+ * for priorities)
+ */
+typedef enum ucl_object_flags {
+ UCL_OBJECT_ALLOCATED_KEY = (1 << 0), /**< An object has key allocated internally */
+ UCL_OBJECT_ALLOCATED_VALUE = (1 << 1), /**< An object has a string value allocated internally */
+ UCL_OBJECT_NEED_KEY_ESCAPE = (1 << 2), /**< The key of an object need to be escaped on output */
+ UCL_OBJECT_EPHEMERAL = (1 << 3), /**< Temporary object that does not need to be freed really */
+ UCL_OBJECT_MULTILINE = (1 << 4), /**< String should be displayed as multiline string */
+ UCL_OBJECT_MULTIVALUE = (1 << 5), /**< Object is a key with multiple values */
+ UCL_OBJECT_INHERITED = (1 << 6), /**< Object has been inherited from another */
+ UCL_OBJECT_BINARY = (1 << 7), /**< Object contains raw binary data */
+ UCL_OBJECT_SQUOTED = (1 << 8) /**< Object has been enclosed in single quotes */
+} ucl_object_flags_t;
+
+/**
+ * Duplicate policy types
+ */
+enum ucl_duplicate_strategy {
+ UCL_DUPLICATE_APPEND = 0, /**< Default policy to merge based on priorities */
+ UCL_DUPLICATE_MERGE, /**< Merge new object with old one */
+ UCL_DUPLICATE_REWRITE, /**< Rewrite old keys */
+ UCL_DUPLICATE_ERROR /**< Stop parsing on duplicate found */
+};
+
+/**
+ * Input format type
+ */
+enum ucl_parse_type {
+ UCL_PARSE_UCL = 0, /**< Default ucl format */
+ UCL_PARSE_MSGPACK, /**< Message pack input format */
+ UCL_PARSE_CSEXP, /**< Canonical S-expressions */
+ UCL_PARSE_AUTO /**< Try to detect parse type */
+};
+
+/**
+ * UCL object structure. Please mention that the most of fields should not be touched by
+ * UCL users. In future, this structure may be converted to private one.
+ */
+typedef struct ucl_object_s {
+ /**
+ * Variant value type
+ */
+ union {
+ int64_t iv; /**< Int value of an object */
+ const char *sv; /**< String value of an object */
+ double dv; /**< Double value of an object */
+ void *av; /**< Array */
+ void *ov; /**< Object */
+ void* ud; /**< Opaque user data */
+ } value;
+ const char *key; /**< Key of an object */
+ struct ucl_object_s *next; /**< Array handle */
+ struct ucl_object_s *prev; /**< Array handle */
+ uint32_t keylen; /**< Length of a key */
+ uint32_t len; /**< Size of an object */
+ uint32_t ref; /**< Reference count */
+ uint16_t flags; /**< Object flags */
+ uint16_t type; /**< Real type */
+ unsigned char* trash_stack[2]; /**< Pointer to allocated chunks */
+} ucl_object_t;
+
+/**
+ * Destructor type for userdata objects
+ * @param ud user specified data pointer
+ */
+typedef void (*ucl_userdata_dtor)(void *ud);
+typedef const char* (*ucl_userdata_emitter)(void *ud);
+
+/** @} */
+
+/**
+ * @defgroup utils Utility functions
+ * A number of utility functions simplify handling of UCL objects
+ *
+ * @{
+ */
+/**
+ * Copy and return a key of an object, returned key is zero-terminated
+ * @param obj CL object
+ * @return zero terminated key
+ */
+UCL_EXTERN char* ucl_copy_key_trash (const ucl_object_t *obj);
+
+/**
+ * Copy and return a string value of an object, returned key is zero-terminated
+ * @param obj CL object
+ * @return zero terminated string representation of object value
+ */
+UCL_EXTERN char* ucl_copy_value_trash (const ucl_object_t *obj);
+
+/**
+ * Creates a new object
+ * @return new object
+ */
+UCL_EXTERN ucl_object_t* ucl_object_new (void) UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Create new object with type specified
+ * @param type type of a new object
+ * @return new object
+ */
+UCL_EXTERN ucl_object_t* ucl_object_typed_new (ucl_type_t type) UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Create new object with type and priority specified
+ * @param type type of a new object
+ * @param priority priority of an object
+ * @return new object
+ */
+UCL_EXTERN ucl_object_t* ucl_object_new_full (ucl_type_t type, unsigned priority)
+ UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Create new object with userdata dtor
+ * @param dtor destructor function
+ * @param emitter emitter for userdata
+ * @param ptr opaque pointer
+ * @return new object
+ */
+UCL_EXTERN ucl_object_t* ucl_object_new_userdata (ucl_userdata_dtor dtor,
+ ucl_userdata_emitter emitter, void *ptr) UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Perform deep copy of an object copying everything
+ * @param other object to copy
+ * @return new object with refcount equal to 1
+ */
+UCL_EXTERN ucl_object_t * ucl_object_copy (const ucl_object_t *other)
+ UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Return the type of an object
+ * @return the object type
+ */
+UCL_EXTERN ucl_type_t ucl_object_type (const ucl_object_t *obj);
+
+/**
+ * Converts ucl object type to its string representation
+ * @param type type of object
+ * @return constant string describing type
+ */
+UCL_EXTERN const char * ucl_object_type_to_string (ucl_type_t type);
+
+/**
+ * Converts string that represents ucl type to real ucl type enum
+ * @param input C string with name of type
+ * @param res resulting target
+ * @return true if `input` is a name of type stored in `res`
+ */
+UCL_EXTERN bool ucl_object_string_to_type (const char *input, ucl_type_t *res);
+
+/**
+ * Convert any string to an ucl object making the specified transformations
+ * @param str fixed size or NULL terminated string
+ * @param len length (if len is zero, than str is treated as NULL terminated)
+ * @param flags conversion flags
+ * @return new object
+ */
+UCL_EXTERN ucl_object_t * ucl_object_fromstring_common (const char *str, size_t len,
+ enum ucl_string_flags flags) UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Create a UCL object from the specified string
+ * @param str NULL terminated string, will be json escaped
+ * @return new object
+ */
+UCL_EXTERN ucl_object_t *ucl_object_fromstring (const char *str) UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Create a UCL object from the specified string
+ * @param str fixed size string, will be json escaped
+ * @param len length of a string
+ * @return new object
+ */
+UCL_EXTERN ucl_object_t *ucl_object_fromlstring (const char *str,
+ size_t len) UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Create an object from an integer number
+ * @param iv number
+ * @return new object
+ */
+UCL_EXTERN ucl_object_t* ucl_object_fromint (int64_t iv) UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Create an object from a float number
+ * @param dv number
+ * @return new object
+ */
+UCL_EXTERN ucl_object_t* ucl_object_fromdouble (double dv) UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Create an object from a boolean
+ * @param bv bool value
+ * @return new object
+ */
+UCL_EXTERN ucl_object_t* ucl_object_frombool (bool bv) UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Insert a object 'elt' to the hash 'top' and associate it with key 'key'
+ * @param top destination object (must be of type UCL_OBJECT)
+ * @param elt element to insert (must NOT be NULL)
+ * @param key key to associate with this object (either const or preallocated)
+ * @param keylen length of the key (or 0 for NULL terminated keys)
+ * @param copy_key make an internal copy of key
+ * @return true if key has been inserted
+ */
+UCL_EXTERN bool ucl_object_insert_key (ucl_object_t *top, ucl_object_t *elt,
+ const char *key, size_t keylen, bool copy_key);
+
+/**
+ * Replace a object 'elt' to the hash 'top' and associate it with key 'key', old object will be unrefed,
+ * if no object has been found this function works like ucl_object_insert_key()
+ * @param top destination object (must be of type UCL_OBJECT)
+ * @param elt element to insert (must NOT be NULL)
+ * @param key key to associate with this object (either const or preallocated)
+ * @param keylen length of the key (or 0 for NULL terminated keys)
+ * @param copy_key make an internal copy of key
+ * @return true if key has been inserted
+ */
+UCL_EXTERN bool ucl_object_replace_key (ucl_object_t *top, ucl_object_t *elt,
+ const char *key, size_t keylen, bool copy_key);
+
+/**
+ * Merge the keys from one object to another object. Overwrite on conflict
+ * @param top destination object (must be of type UCL_OBJECT)
+ * @param elt element to insert (must be of type UCL_OBJECT)
+ * @param copy copy rather than reference the elements
+ * @return true if all keys have been merged
+ */
+UCL_EXTERN bool ucl_object_merge (ucl_object_t *top, ucl_object_t *elt, bool copy);
+
+/**
+ * Delete a object associated with key 'key', old object will be unrefered,
+ * @param top object
+ * @param key key associated to the object to remove
+ * @param keylen length of the key (or 0 for NULL terminated keys)
+ */
+UCL_EXTERN bool ucl_object_delete_keyl (ucl_object_t *top,
+ const char *key, size_t keylen);
+
+/**
+ * Delete a object associated with key 'key', old object will be unrefered,
+ * @param top object
+ * @param key key associated to the object to remove
+ */
+UCL_EXTERN bool ucl_object_delete_key (ucl_object_t *top,
+ const char *key);
+
+
+/**
+ * Removes `key` from `top` object, returning the object that was removed. This
+ * object is not released, caller must unref the returned object when it is no
+ * longer needed.
+ * @param top object
+ * @param key key to remove
+ * @param keylen length of the key (or 0 for NULL terminated keys)
+ * @return removed object or NULL if object has not been found
+ */
+UCL_EXTERN ucl_object_t* ucl_object_pop_keyl (ucl_object_t *top, const char *key,
+ size_t keylen) UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Removes `key` from `top` object returning the object that was removed. This
+ * object is not released, caller must unref the returned object when it is no
+ * longer needed.
+ * @param top object
+ * @param key key to remove
+ * @return removed object or NULL if object has not been found
+ */
+UCL_EXTERN ucl_object_t* ucl_object_pop_key (ucl_object_t *top, const char *key)
+ UCL_WARN_UNUSED_RESULT;
+
+/**
+ * Insert a object 'elt' to the hash 'top' and associate it with key 'key', if
+ * the specified key exist, try to merge its content
+ * @param top destination object (must be of type UCL_OBJECT)
+ * @param elt element to insert (must NOT be NULL)
+ * @param key key to associate with this object (either const or preallocated)
+ * @param keylen length of the key (or 0 for NULL terminated keys)
+ * @param copy_key make an internal copy of key
+ * @return true if key has been inserted
+ */
+UCL_EXTERN bool ucl_object_insert_key_merged (ucl_object_t *top, ucl_object_t *elt,
+ const char *key, size_t keylen, bool copy_key);
+
+/**
+ * Reserve space in ucl array or object for `elt` elements
+ * @param obj object to reserve
+ * @param reserved size to reserve in an object
+ * @return 0 on success, -1 on failure (i.e. ENOMEM)
+ */
+UCL_EXTERN bool ucl_object_reserve (ucl_object_t *obj, size_t reserved);
+
+/**
+ * Append an element to the end of array object
+ * @param top destination object (must NOT be NULL)
+ * @param elt element to append (must NOT be NULL)
+ * @return true if value has been inserted
+ */
+UCL_EXTERN bool ucl_array_append (ucl_object_t *top,
+ ucl_object_t *elt);
+
+/**
+ * Append an element to the start of array object
+ * @param top destination object (must NOT be NULL)
+ * @param elt element to append (must NOT be NULL)
+ * @return true if value has been inserted
+ */
+UCL_EXTERN bool ucl_array_prepend (ucl_object_t *top,
+ ucl_object_t *elt);
+
+/**
+ * Merge all elements of second array into the first array
+ * @param top destination array (must be of type UCL_ARRAY)
+ * @param elt array to copy elements from (must be of type UCL_ARRAY)
+ * @param copy copy elements instead of referencing them
+ * @return true if arrays were merged
+ */
+UCL_EXTERN bool ucl_array_merge (ucl_object_t *top, ucl_object_t *elt,
+ bool copy);
+
+/**
+ * Removes an element `elt` from the array `top`, returning the object that was
+ * removed. This object is not released, caller must unref the returned object
+ * when it is no longer needed.
+ * @param top array ucl object
+ * @param elt element to remove
+ * @return removed element or NULL if `top` is NULL or not an array
+ */
+UCL_EXTERN ucl_object_t* ucl_array_delete (ucl_object_t *top,
+ ucl_object_t *elt);
+
+/**
+ * Returns the first element of the array `top`
+ * @param top array ucl object
+ * @return element or NULL if `top` is NULL or not an array
+ */
+UCL_EXTERN const ucl_object_t* ucl_array_head (const ucl_object_t *top);
+
+/**
+ * Returns the last element of the array `top`
+ * @param top array ucl object
+ * @return element or NULL if `top` is NULL or not an array
+ */
+UCL_EXTERN const ucl_object_t* ucl_array_tail (const ucl_object_t *top);
+
+/**
+ * Removes the last element from the array `top`, returning the object that was
+ * removed. This object is not released, caller must unref the returned object
+ * when it is no longer needed.
+ * @param top array ucl object
+ * @return removed element or NULL if `top` is NULL or not an array
+ */
+UCL_EXTERN ucl_object_t* ucl_array_pop_last (ucl_object_t *top);
+
+/**
+ * Removes the first element from the array `top`, returning the object that was
+ * removed. This object is not released, caller must unref the returned object
+ * when it is no longer needed.
+ * @param top array ucl object
+ * @return removed element or NULL if `top` is NULL or not an array
+ */
+UCL_EXTERN ucl_object_t* ucl_array_pop_first (ucl_object_t *top);
+
+/**
+ * Return size of the array `top`
+ * @param top object to get size from (must be of type UCL_ARRAY)
+ * @return size of the array
+ */
+UCL_EXTERN unsigned int ucl_array_size (const ucl_object_t *top);
+
+/**
+ * Return object identified by index of the array `top`
+ * @param top object to get a key from (must be of type UCL_ARRAY)
+ * @param index array index to return
+ * @return object at the specified index or NULL if index is not found
+ */
+UCL_EXTERN const ucl_object_t* ucl_array_find_index (const ucl_object_t *top,
+ unsigned int index);
+
+/**
+ * Return the index of `elt` in the array `top`
+ * @param top object to get a key from (must be of type UCL_ARRAY)
+ * @param elt element to find index of (must NOT be NULL)
+ * @return index of `elt` in the array `top or (unsigned int)-1 if `elt` is not found
+ */
+UCL_EXTERN unsigned int ucl_array_index_of (ucl_object_t *top,
+ ucl_object_t *elt);
+
+/**
+ * Replace an element in an array with a different element, returning the object
+ * that was replaced. This object is not released, caller must unref the
+ * returned object when it is no longer needed.
+ * @param top destination object (must be of type UCL_ARRAY)
+ * @param elt element to append (must NOT be NULL)
+ * @param index array index in destination to overwrite with elt
+ * @return object that was replaced or NULL if index is not found
+ */
+ucl_object_t *
+ucl_array_replace_index (ucl_object_t *top, ucl_object_t *elt,
+ unsigned int index);
+
+/**
+ * Append a element to another element forming an implicit array
+ * @param head head to append (may be NULL)
+ * @param elt new element
+ * @return the new implicit array
+ */
+UCL_EXTERN ucl_object_t * ucl_elt_append (ucl_object_t *head,
+ ucl_object_t *elt);
+
+/**
+ * Converts an object to double value
+ * @param obj CL object
+ * @param target target double variable
+ * @return true if conversion was successful
+ */
+UCL_EXTERN bool ucl_object_todouble_safe (const ucl_object_t *obj, double *target);
+
+/**
+ * Unsafe version of \ref ucl_obj_todouble_safe
+ * @param obj CL object
+ * @return double value
+ */
+UCL_EXTERN double ucl_object_todouble (const ucl_object_t *obj);
+
+/**
+ * Converts an object to integer value
+ * @param obj CL object
+ * @param target target integer variable
+ * @return true if conversion was successful
+ */
+UCL_EXTERN bool ucl_object_toint_safe (const ucl_object_t *obj, int64_t *target);
+
+/**
+ * Unsafe version of \ref ucl_obj_toint_safe
+ * @param obj CL object
+ * @return int value
+ */
+UCL_EXTERN int64_t ucl_object_toint (const ucl_object_t *obj);
+
+/**
+ * Converts an object to boolean value
+ * @param obj CL object
+ * @param target target boolean variable
+ * @return true if conversion was successful
+ */
+UCL_EXTERN bool ucl_object_toboolean_safe (const ucl_object_t *obj, bool *target);
+
+/**
+ * Unsafe version of \ref ucl_obj_toboolean_safe
+ * @param obj CL object
+ * @return boolean value
+ */
+UCL_EXTERN bool ucl_object_toboolean (const ucl_object_t *obj);
+
+/**
+ * Converts an object to string value
+ * @param obj CL object
+ * @param target target string variable, no need to free value
+ * @return true if conversion was successful
+ */
+UCL_EXTERN bool ucl_object_tostring_safe (const ucl_object_t *obj, const char **target);
+
+/**
+ * Unsafe version of \ref ucl_obj_tostring_safe
+ * @param obj CL object
+ * @return string value
+ */
+UCL_EXTERN const char* ucl_object_tostring (const ucl_object_t *obj);
+
+/**
+ * Convert any object to a string in JSON notation if needed
+ * @param obj CL object
+ * @return string value
+ */
+UCL_EXTERN const char* ucl_object_tostring_forced (const ucl_object_t *obj);
+
+/**
+ * Return string as char * and len, string may be not zero terminated, more efficient that \ref ucl_obj_tostring as it
+ * allows zero-copy (if #UCL_PARSER_ZEROCOPY has been used during parsing)
+ * @param obj CL object
+ * @param target target string variable, no need to free value
+ * @param tlen target length
+ * @return true if conversion was successful
+ */
+UCL_EXTERN bool ucl_object_tolstring_safe (const ucl_object_t *obj,
+ const char **target, size_t *tlen);
+
+/**
+ * Unsafe version of \ref ucl_obj_tolstring_safe
+ * @param obj CL object
+ * @return string value
+ */
+UCL_EXTERN const char* ucl_object_tolstring (const ucl_object_t *obj, size_t *tlen);
+
+/**
+ * Return object identified by a key in the specified object
+ * @param obj object to get a key from (must be of type UCL_OBJECT)
+ * @param key key to search
+ * @return object matching the specified key or NULL if key was not found
+ */
+UCL_EXTERN const ucl_object_t* ucl_object_lookup (const ucl_object_t *obj,
+ const char *key);
+#define ucl_object_find_key ucl_object_lookup
+
+/**
+ * Return object identified by a key in the specified object, if the first key is
+ * not found then look for the next one. This process is repeated unless
+ * the next argument in the list is not NULL. So, `ucl_object_find_any_key(obj, key, NULL)`
+ * is equal to `ucl_object_find_key(obj, key)`
+ * @param obj object to get a key from (must be of type UCL_OBJECT)
+ * @param key key to search
+ * @param ... list of alternative keys to search (NULL terminated)
+ * @return object matching the specified key or NULL if key was not found
+ */
+UCL_EXTERN const ucl_object_t* ucl_object_lookup_any (const ucl_object_t *obj,
+ const char *key, ...);
+#define ucl_object_find_any_key ucl_object_lookup_any
+
+/**
+ * Return object identified by a fixed size key in the specified object
+ * @param obj object to get a key from (must be of type UCL_OBJECT)
+ * @param key key to search
+ * @param klen length of a key
+ * @return object matching the specified key or NULL if key was not found
+ */
+UCL_EXTERN const ucl_object_t* ucl_object_lookup_len (const ucl_object_t *obj,
+ const char *key, size_t klen);
+#define ucl_object_find_keyl ucl_object_lookup_len
+
+/**
+ * Return object identified by dot notation string
+ * @param obj object to search in
+ * @param path dot.notation.path to the path to lookup. May use numeric .index on arrays
+ * @return object matched the specified path or NULL if path is not found
+ */
+UCL_EXTERN const ucl_object_t *ucl_object_lookup_path (const ucl_object_t *obj,
+ const char *path);
+#define ucl_lookup_path ucl_object_lookup_path
+
+/**
+ * Return object identified by object notation string using arbitrary delimiter
+ * @param obj object to search in
+ * @param path dot.notation.path to the path to lookup. May use numeric .index on arrays
+ * @param sep the sepatorator to use in place of . (incase keys have . in them)
+ * @return object matched the specified path or NULL if path is not found
+ */
+UCL_EXTERN const ucl_object_t *ucl_object_lookup_path_char (const ucl_object_t *obj,
+ const char *path, char sep);
+#define ucl_lookup_path_char ucl_object_lookup_path_char
+
+/**
+ * Returns a key of an object as a NULL terminated string
+ * @param obj CL object
+ * @return key or NULL if there is no key
+ */
+UCL_EXTERN const char* ucl_object_key (const ucl_object_t *obj);
+
+/**
+ * Returns a key of an object as a fixed size string (may be more efficient)
+ * @param obj CL object
+ * @param len target key length
+ * @return key pointer
+ */
+UCL_EXTERN const char* ucl_object_keyl (const ucl_object_t *obj, size_t *len);
+
+/**
+ * Increase reference count for an object
+ * @param obj object to ref
+ * @return the referenced object
+ */
+UCL_EXTERN ucl_object_t* ucl_object_ref (const ucl_object_t *obj);
+
+/**
+ * Free ucl object
+ * @param obj ucl object to free
+ */
+UCL_DEPRECATED(UCL_EXTERN void ucl_object_free (ucl_object_t *obj));
+
+/**
+ * Decrease reference count for an object
+ * @param obj object to unref
+ */
+UCL_EXTERN void ucl_object_unref (ucl_object_t *obj);
+
+/**
+ * Compare objects `o1` and `o2`
+ * @param o1 the first object
+ * @param o2 the second object
+ * @return values >0, 0 and <0 if `o1` is more than, equal and less than `o2`.
+ * The order of comparison:
+ * 1) Type of objects
+ * 2) Size of objects
+ * 3) Content of objects
+ */
+UCL_EXTERN int ucl_object_compare (const ucl_object_t *o1,
+ const ucl_object_t *o2);
+
+/**
+ * Compare objects `o1` and `o2` useful for sorting
+ * @param o1 the first object
+ * @param o2 the second object
+ * @return values >0, 0 and <0 if `o1` is more than, equal and less than `o2`.
+ * The order of comparison:
+ * 1) Type of objects
+ * 2) Size of objects
+ * 3) Content of objects
+ */
+UCL_EXTERN int ucl_object_compare_qsort (const ucl_object_t **o1,
+ const ucl_object_t **o2);
+
+/**
+ * Sort UCL array using `cmp` compare function
+ * @param ar
+ * @param cmp
+ */
+UCL_EXTERN void ucl_object_array_sort (ucl_object_t *ar,
+ int (*cmp)(const ucl_object_t **o1, const ucl_object_t **o2));
+
+enum ucl_object_keys_sort_flags {
+ UCL_SORT_KEYS_DEFAULT = 0,
+ UCL_SORT_KEYS_ICASE = (1u << 0u),
+ UCL_SORT_KEYS_RECURSIVE = (1u << 1u),
+};
+/***
+ * Sorts keys in object in place
+ * @param obj
+ * @param how
+ */
+UCL_EXTERN void ucl_object_sort_keys (ucl_object_t *obj,
+ enum ucl_object_keys_sort_flags how);
+
+/**
+ * Get the priority for specific UCL object
+ * @param obj any ucl object
+ * @return priority of an object
+ */
+UCL_EXTERN unsigned int ucl_object_get_priority (const ucl_object_t *obj);
+
+/**
+ * Set explicit priority of an object.
+ * @param obj any ucl object
+ * @param priority new priroity value (only 4 least significant bits are considred)
+ */
+UCL_EXTERN void ucl_object_set_priority (ucl_object_t *obj,
+ unsigned int priority);
+
+/**
+ * Opaque iterator object
+ */
+typedef void* ucl_object_iter_t;
+
+/**
+ * Get next key from an object
+ * @param obj object to iterate
+ * @param iter opaque iterator, must be set to NULL on the first call:
+ * ucl_object_iter_t it = NULL;
+ * while ((cur = ucl_iterate_object (obj, &it)) != NULL) ...
+ * @param ep pointer record exception (such as ENOMEM), could be NULL
+ * @return the next object or NULL
+ */
+UCL_EXTERN const ucl_object_t* ucl_object_iterate_with_error (const ucl_object_t *obj,
+ ucl_object_iter_t *iter, bool expand_values, int *ep);
+
+#define ucl_iterate_object ucl_object_iterate
+#define ucl_object_iterate(ob, it, ev) ucl_object_iterate_with_error((ob), (it), (ev), NULL)
+
+/**
+ * Create new safe iterator for the specified object
+ * @param obj object to iterate
+ * @return new iterator object that should be used with safe iterators API only
+ */
+UCL_EXTERN ucl_object_iter_t ucl_object_iterate_new (const ucl_object_t *obj)
+ UCL_WARN_UNUSED_RESULT;
+/**
+ * Check safe iterator object after performing some operations on it
+ * (such as ucl_object_iterate_safe()) to see if operation has encountered
+ * fatal exception while performing that operation (e.g. ENOMEM).
+ * @param iter opaque iterator
+ * @return true if exception has occured, false otherwise
+ */
+UCL_EXTERN bool ucl_object_iter_chk_excpn(ucl_object_iter_t *it);
+
+/**
+ * Reset initialized iterator to a new object
+ * @param obj new object to iterate
+ * @return modified iterator object
+ */
+UCL_EXTERN ucl_object_iter_t ucl_object_iterate_reset (ucl_object_iter_t it,
+ const ucl_object_t *obj);
+
+/**
+ * Get the next object from the `obj`. This function iterates over arrays, objects
+ * and implicit arrays
+ * @param iter safe iterator
+ * @param expand_values expand explicit arrays and objects
+ * @return the next object in sequence
+ */
+UCL_EXTERN const ucl_object_t* ucl_object_iterate_safe (ucl_object_iter_t iter,
+ bool expand_values);
+/**
+ * Iteration type enumerator
+ */
+enum ucl_iterate_type {
+ UCL_ITERATE_EXPLICIT = 1 << 0, /**< Iterate just explicit arrays and objects */
+ UCL_ITERATE_IMPLICIT = 1 << 1, /**< Iterate just implicit arrays */
+ UCL_ITERATE_BOTH = (1 << 0) | (1 << 1), /**< Iterate both explicit and implicit arrays*/
+};
+
+/**
+ * Get the next object from the `obj`. This function iterates over arrays, objects
+ * and implicit arrays if needed
+ * @param iter safe iterator
+ * @param
+ * @return the next object in sequence
+ */
+UCL_EXTERN const ucl_object_t* ucl_object_iterate_full (ucl_object_iter_t iter,
+ enum ucl_iterate_type type);
+
+/**
+ * Free memory associated with the safe iterator
+ * @param it safe iterator object
+ */
+UCL_EXTERN void ucl_object_iterate_free (ucl_object_iter_t it);
+
+/** @} */
+
+
+/**
+ * @defgroup parser Parsing functions
+ * These functions are used to parse UCL objects
+ *
+ * @{
+ */
+
+/**
+ * Macro handler for a parser
+ * @param data the content of macro
+ * @param len the length of content
+ * @param arguments arguments object
+ * @param ud opaque user data
+ * @param err error pointer
+ * @return true if macro has been parsed
+ */
+typedef bool (*ucl_macro_handler) (const unsigned char *data, size_t len,
+ const ucl_object_t *arguments,
+ void* ud);
+
+/**
+ * Context dependent macro handler for a parser
+ * @param data the content of macro
+ * @param len the length of content
+ * @param arguments arguments object
+ * @param context previously parsed context
+ * @param ud opaque user data
+ * @param err error pointer
+ * @return true if macro has been parsed
+ */
+typedef bool (*ucl_context_macro_handler) (const unsigned char *data, size_t len,
+ const ucl_object_t *arguments,
+ const ucl_object_t *context,
+ void* ud);
+
+/* Opaque parser */
+struct ucl_parser;
+
+/**
+ * Creates new parser object
+ * @param pool pool to allocate memory from
+ * @return new parser object
+ */
+UCL_EXTERN struct ucl_parser* ucl_parser_new (int flags);
+
+/**
+ * Sets the default priority for the parser applied to chunks that do not
+ * specify priority explicitly
+ * @param parser parser object
+ * @param prio default priority (0 .. 16)
+ * @return true if parser's default priority was set
+ */
+UCL_EXTERN bool ucl_parser_set_default_priority (struct ucl_parser *parser,
+ unsigned prio);
+/**
+ * Gets the default priority for the parser applied to chunks that do not
+ * specify priority explicitly
+ * @param parser parser object
+ * @return true default priority (0 .. 16), -1 for failure
+ */
+UCL_EXTERN int ucl_parser_get_default_priority (struct ucl_parser *parser);
+
+/**
+ * Register new handler for a macro
+ * @param parser parser object
+ * @param macro macro name (without leading dot)
+ * @param handler handler (it is called immediately after macro is parsed)
+ * @param ud opaque user data for a handler
+ * @return true on success, false on failure (i.e. ENOMEM)
+ */
+UCL_EXTERN bool ucl_parser_register_macro (struct ucl_parser *parser,
+ const char *macro,
+ ucl_macro_handler handler, void* ud);
+
+/**
+ * Register new context dependent handler for a macro
+ * @param parser parser object
+ * @param macro macro name (without leading dot)
+ * @param handler handler (it is called immediately after macro is parsed)
+ * @param ud opaque user data for a handler
+ * @return true on success, false on failure (i.e. ENOMEM)
+ */
+UCL_EXTERN bool ucl_parser_register_context_macro (struct ucl_parser *parser,
+ const char *macro,
+ ucl_context_macro_handler handler,
+ void* ud);
+
+/**
+ * Handler to detect unregistered variables
+ * @param data variable data
+ * @param len length of variable
+ * @param replace (out) replace value for variable
+ * @param replace_len (out) replace length for variable
+ * @param need_free (out) UCL will free `dest` after usage
+ * @param ud opaque userdata
+ * @return true if variable
+ */
+typedef bool (*ucl_variable_handler) (const unsigned char *data, size_t len,
+ unsigned char **replace, size_t *replace_len, bool *need_free, void* ud);
+
+/**
+ * Register new parser variable
+ * @param parser parser object
+ * @param var variable name
+ * @param value variable value
+ */
+UCL_EXTERN void ucl_parser_register_variable (struct ucl_parser *parser, const char *var,
+ const char *value);
+
+/**
+ * Set handler for unknown variables
+ * @param parser parser structure
+ * @param handler desired handler
+ * @param ud opaque data for the handler
+ */
+UCL_EXTERN void ucl_parser_set_variables_handler (struct ucl_parser *parser,
+ ucl_variable_handler handler, void *ud);
+
+/**
+ * Load new chunk to a parser
+ * @param parser parser structure
+ * @param data the pointer to the beginning of a chunk
+ * @param len the length of a chunk
+ * @return true if chunk has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_add_chunk (struct ucl_parser *parser,
+ const unsigned char *data, size_t len);
+
+/**
+ * Load new chunk to a parser with the specified priority
+ * @param parser parser structure
+ * @param data the pointer to the beginning of a chunk
+ * @param len the length of a chunk
+ * @param priority the desired priority of a chunk (only 4 least significant bits
+ * are considered for this parameter)
+ * @return true if chunk has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_add_chunk_priority (struct ucl_parser *parser,
+ const unsigned char *data, size_t len, unsigned priority);
+
+/**
+ * Insert new chunk to a parser (must have previously processed data with an existing top object)
+ * @param parser parser structure
+ * @param data the pointer to the beginning of a chunk
+ * @param len the length of a chunk
+ * @return true if chunk has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_insert_chunk (struct ucl_parser *parser,
+ const unsigned char *data, size_t len);
+
+/**
+ * Full version of ucl_add_chunk with priority and duplicate strategy
+ * @param parser parser structure
+ * @param data the pointer to the beginning of a chunk
+ * @param len the length of a chunk
+ * @param priority the desired priority of a chunk (only 4 least significant bits
+ * are considered for this parameter)
+ * @param strat duplicates merging strategy
+ * @param parse_type input format
+ * @return true if chunk has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_add_chunk_full (struct ucl_parser *parser,
+ const unsigned char *data, size_t len, unsigned priority,
+ enum ucl_duplicate_strategy strat, enum ucl_parse_type parse_type);
+
+/**
+ * Load ucl object from a string
+ * @param parser parser structure
+ * @param data the pointer to the string
+ * @param len the length of the string, if `len` is 0 then `data` must be zero-terminated string
+ * @return true if string has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_add_string (struct ucl_parser *parser,
+ const char *data, size_t len);
+
+/**
+ * Load ucl object from a string
+ * @param parser parser structure
+ * @param data the pointer to the string
+ * @param len the length of the string, if `len` is 0 then `data` must be zero-terminated string
+ * @param priority the desired priority of a chunk (only 4 least significant bits
+ * are considered for this parameter)
+ * @return true if string has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_add_string_priority (struct ucl_parser *parser,
+ const char *data, size_t len, unsigned priority);
+
+/**
+ * Load and add data from a file
+ * @param parser parser structure
+ * @param filename the name of file
+ * @param err if *err is NULL it is set to parser error
+ * @return true if chunk has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_add_file (struct ucl_parser *parser,
+ const char *filename);
+
+/**
+ * Load and add data from a file
+ * @param parser parser structure
+ * @param filename the name of file
+ * @param err if *err is NULL it is set to parser error
+ * @param priority the desired priority of a chunk (only 4 least significant bits
+ * are considered for this parameter)
+ * @return true if chunk has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_add_file_priority (struct ucl_parser *parser,
+ const char *filename, unsigned priority);
+
+/**
+ * Load and add data from a file
+ * @param parser parser structure
+ * @param filename the name of file
+ * @param priority the desired priority of a chunk (only 4 least significant bits
+ * are considered for this parameter)
+ * @param strat Merge strategy to use while parsing this file
+ * @param parse_type Parser type to use while parsing this file
+ * @return true if chunk has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_add_file_full (struct ucl_parser *parser, const char *filename,
+ unsigned priority, enum ucl_duplicate_strategy strat,
+ enum ucl_parse_type parse_type);
+
+/**
+ * Load and add data from a file descriptor
+ * @param parser parser structure
+ * @param filename the name of file
+ * @param err if *err is NULL it is set to parser error
+ * @return true if chunk has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_add_fd (struct ucl_parser *parser,
+ int fd);
+
+/**
+ * Load and add data from a file descriptor
+ * @param parser parser structure
+ * @param filename the name of file
+ * @param err if *err is NULL it is set to parser error
+ * @param priority the desired priority of a chunk (only 4 least significant bits
+ * are considered for this parameter)
+ * @return true if chunk has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_add_fd_priority (struct ucl_parser *parser,
+ int fd, unsigned priority);
+
+/**
+ * Load and add data from a file descriptor
+ * @param parser parser structure
+ * @param filename the name of file
+ * @param err if *err is NULL it is set to parser error
+ * @param priority the desired priority of a chunk (only 4 least significant bits
+ * are considered for this parameter)
+ * @param strat Merge strategy to use while parsing this file
+ * @param parse_type Parser type to use while parsing this file
+ * @return true if chunk has been added and false in case of error
+ */
+UCL_EXTERN bool ucl_parser_add_fd_full (struct ucl_parser *parser, int fd,
+ unsigned priority, enum ucl_duplicate_strategy strat,
+ enum ucl_parse_type parse_type);
+
+/**
+ * Provide a UCL_ARRAY of paths to search for include files. The object is
+ * copied so caller must unref the object.
+ * @param parser parser structure
+ * @param paths UCL_ARRAY of paths to search
+ * @return true if the path search array was replaced in the parser
+ */
+UCL_EXTERN bool ucl_set_include_path (struct ucl_parser *parser,
+ ucl_object_t *paths);
+
+/**
+ * Get a top object for a parser (refcount is increased)
+ * @param parser parser structure
+ * @param err if *err is NULL it is set to parser error
+ * @return top parser object or NULL
+ */
+UCL_EXTERN ucl_object_t* ucl_parser_get_object (struct ucl_parser *parser);
+
+/**
+ * Get the current stack object as stack accessor function for use in macro
+ * functions (refcount is increased)
+ * @param parser parser object
+ * @param depth depth of stack to retrieve (top is 0)
+ * @return current stack object or NULL
+ */
+UCL_EXTERN ucl_object_t* ucl_parser_get_current_stack_object (struct ucl_parser *parser, unsigned int depth);
+
+/**
+ * Peek at the character at the current chunk position
+ * @param parser parser structure
+ * @return current chunk position character
+ */
+UCL_EXTERN unsigned char ucl_parser_chunk_peek (struct ucl_parser *parser);
+
+/**
+ * Skip the character at the current chunk position
+ * @param parser parser structure
+ * @return success boolean
+ */
+UCL_EXTERN bool ucl_parser_chunk_skip (struct ucl_parser *parser);
+
+/**
+ * Get the error string if parsing has been failed
+ * @param parser parser object
+ * @return error description
+ */
+UCL_EXTERN const char *ucl_parser_get_error (struct ucl_parser *parser);
+
+/**
+ * Get the code of the last error
+ * @param parser parser object
+ * @return error code
+ */
+UCL_EXTERN int ucl_parser_get_error_code (struct ucl_parser *parser);
+
+/**
+ * Get the current column number within parser
+ * @param parser parser object
+ * @return current column number
+ */
+UCL_EXTERN unsigned ucl_parser_get_column (struct ucl_parser *parser);
+
+/**
+ * Get the current line number within parser
+ * @param parser parser object
+ * @return current line number
+ */
+UCL_EXTERN unsigned ucl_parser_get_linenum (struct ucl_parser *parser);
+
+/**
+ * Clear the error in the parser
+ * @param parser parser object
+ */
+UCL_EXTERN void ucl_parser_clear_error (struct ucl_parser *parser);
+
+/**
+ * Free ucl parser object
+ * @param parser parser object
+ */
+UCL_EXTERN void ucl_parser_free (struct ucl_parser *parser);
+
+/**
+ * Get constant opaque pointer to comments structure for this parser. Increase
+ * refcount to prevent this object to be destroyed on parser's destruction
+ * @param parser parser structure
+ * @return ucl comments pointer or NULL
+ */
+UCL_EXTERN const ucl_object_t * ucl_parser_get_comments (struct ucl_parser *parser);
+
+/**
+ * Utility function to find a comment object for the specified object in the input
+ * @param comments comments object
+ * @param srch search object
+ * @return string comment enclosed in ucl_object_t
+ */
+UCL_EXTERN const ucl_object_t * ucl_comments_find (const ucl_object_t *comments,
+ const ucl_object_t *srch);
+
+/**
+ * Move comment from `from` object to `to` object
+ * @param comments comments object
+ * @param what source object
+ * @param with destination object
+ * @return `true` if `from` has comment and it has been moved to `to`
+ */
+UCL_EXTERN bool ucl_comments_move (ucl_object_t *comments,
+ const ucl_object_t *from, const ucl_object_t *to);
+
+/**
+ * Adds a new comment for an object
+ * @param comments comments object
+ * @param obj object to add comment to
+ * @param comment string representation of a comment
+ */
+UCL_EXTERN void ucl_comments_add (ucl_object_t *comments,
+ const ucl_object_t *obj, const char *comment);
+
+/**
+ * Add new public key to parser for signatures check
+ * @param parser parser object
+ * @param key PEM representation of a key
+ * @param len length of the key
+ * @param err if *err is NULL it is set to parser error
+ * @return true if a key has been successfully added
+ */
+UCL_EXTERN bool ucl_parser_pubkey_add (struct ucl_parser *parser,
+ const unsigned char *key, size_t len);
+
+/**
+ * Set FILENAME and CURDIR variables in parser
+ * @param parser parser object
+ * @param filename filename to set or NULL to set FILENAME to "undef" and CURDIR to getcwd()
+ * @param need_expand perform realpath() if this variable is true and filename is not NULL
+ * @return true if variables has been set
+ */
+UCL_EXTERN bool ucl_parser_set_filevars (struct ucl_parser *parser, const char *filename,
+ bool need_expand);
+
+/**
+ * Returns current file for the parser
+ * @param parser parser object
+ * @return current file or NULL if parsing memory
+ */
+UCL_EXTERN const char *ucl_parser_get_cur_file (struct ucl_parser *parser);
+
+/**
+ * Defines special handler for certain types of data (identified by magic)
+ */
+typedef bool (*ucl_parser_special_handler_t) (struct ucl_parser *parser,
+ const unsigned char *source, size_t source_len,
+ unsigned char **destination, size_t *dest_len,
+ void *user_data);
+
+/**
+ * Special handler flags
+ */
+enum ucl_special_handler_flags {
+ UCL_SPECIAL_HANDLER_DEFAULT = 0,
+ UCL_SPECIAL_HANDLER_PREPROCESS_ALL = (1u << 0),
+};
+
+/**
+ * Special handler structure
+ */
+struct ucl_parser_special_handler {
+ const unsigned char *magic;
+ size_t magic_len;
+ enum ucl_special_handler_flags flags;
+ ucl_parser_special_handler_t handler;
+ void (*free_function) (unsigned char *data, size_t len, void *user_data);
+ void *user_data;
+ struct ucl_parser_special_handler *next; /* Used internally */
+};
+
+/**
+ * Add special handler for a parser, handles special sequences identified by magic
+ * @param parser parser structure
+ * @param handler handler structure
+ */
+UCL_EXTERN void ucl_parser_add_special_handler (struct ucl_parser *parser,
+ struct ucl_parser_special_handler *handler);
+
+/**
+ * Handler for include traces:
+ * @param parser parser object
+ * @param parent where include is done from
+ * @param args arguments to an include
+ * @param path path of the include
+ * @param pathlen length of the path
+ * @param user_data opaque userdata
+ */
+typedef void (ucl_include_trace_func_t) (struct ucl_parser *parser,
+ const ucl_object_t *parent,
+ const ucl_object_t *args,
+ const char *path,
+ size_t pathlen,
+ void *user_data);
+
+/**
+ * Register trace function for an include handler
+ * @param parser parser object
+ * @param func function to trace includes
+ * @param user_data opaque data
+ */
+UCL_EXTERN void ucl_parser_set_include_tracer (struct ucl_parser *parser,
+ ucl_include_trace_func_t func,
+ void *user_data);
+
+/** @} */
+
+/**
+ * @defgroup emitter Emitting functions
+ * These functions are used to serialise UCL objects to some string representation.
+ *
+ * @{
+ */
+
+struct ucl_emitter_context;
+/**
+ * Structure using for emitter callbacks
+ */
+struct ucl_emitter_functions {
+ /** Append a single character */
+ int (*ucl_emitter_append_character) (unsigned char c, size_t nchars, void *ud);
+ /** Append a string of a specified length */
+ int (*ucl_emitter_append_len) (unsigned const char *str, size_t len, void *ud);
+ /** Append a 64 bit integer */
+ int (*ucl_emitter_append_int) (int64_t elt, void *ud);
+ /** Append floating point element */
+ int (*ucl_emitter_append_double) (double elt, void *ud);
+ /** Free userdata */
+ void (*ucl_emitter_free_func)(void *ud);
+ /** Opaque userdata pointer */
+ void *ud;
+};
+
+struct ucl_emitter_operations {
+ /** Write a primitive element */
+ void (*ucl_emitter_write_elt) (struct ucl_emitter_context *ctx,
+ const ucl_object_t *obj, bool first, bool print_key);
+ /** Start ucl object */
+ void (*ucl_emitter_start_object) (struct ucl_emitter_context *ctx,
+ const ucl_object_t *obj, bool print_key);
+ /** End ucl object */
+ void (*ucl_emitter_end_object) (struct ucl_emitter_context *ctx,
+ const ucl_object_t *obj);
+ /** Start ucl array */
+ void (*ucl_emitter_start_array) (struct ucl_emitter_context *ctx,
+ const ucl_object_t *obj, bool print_key);
+ void (*ucl_emitter_end_array) (struct ucl_emitter_context *ctx,
+ const ucl_object_t *obj);
+};
+
+/**
+ * Structure that defines emitter functions
+ */
+struct ucl_emitter_context {
+ /** Name of emitter (e.g. json, compact_json) */
+ const char *name;
+ /** Unique id (e.g. UCL_EMIT_JSON for standard emitters */
+ int id;
+ /** A set of output functions */
+ const struct ucl_emitter_functions *func;
+ /** A set of output operations */
+ const struct ucl_emitter_operations *ops;
+ /** Current amount of indent tabs */
+ unsigned int indent;
+ /** Top level object */
+ const ucl_object_t *top;
+ /** Optional comments */
+ const ucl_object_t *comments;
+};
+
+/**
+ * Emit object to a string
+ * @param obj object
+ * @param emit_type if type is #UCL_EMIT_JSON then emit json, if type is
+ * #UCL_EMIT_CONFIG then emit config like object
+ * @return dump of an object (must be freed after using) or NULL in case of error
+ */
+UCL_EXTERN unsigned char *ucl_object_emit (const ucl_object_t *obj,
+ enum ucl_emitter emit_type);
+
+/**
+ * Emit object to a string that can contain `\0` inside
+ * @param obj object
+ * @param emit_type if type is #UCL_EMIT_JSON then emit json, if type is
+ * #UCL_EMIT_CONFIG then emit config like object
+ * @param len the resulting length
+ * @return dump of an object (must be freed after using) or NULL in case of error
+ */
+UCL_EXTERN unsigned char *ucl_object_emit_len (const ucl_object_t *obj,
+ enum ucl_emitter emit_type, size_t *len);
+
+/**
+ * Emit object to a string
+ * @param obj object
+ * @param emit_type if type is #UCL_EMIT_JSON then emit json, if type is
+ * #UCL_EMIT_CONFIG then emit config like object
+ * @param emitter a set of emitter functions
+ * @param comments optional comments for the parser
+ * @return dump of an object (must be freed after using) or NULL in case of error
+ */
+UCL_EXTERN bool ucl_object_emit_full (const ucl_object_t *obj,
+ enum ucl_emitter emit_type,
+ struct ucl_emitter_functions *emitter,
+ const ucl_object_t *comments);
+
+/**
+ * Start streamlined UCL object emitter
+ * @param obj top UCL object
+ * @param emit_type emit type
+ * @param emitter a set of emitter functions
+ * @return new streamlined context that should be freed by
+ * `ucl_object_emit_streamline_finish`
+ */
+UCL_EXTERN struct ucl_emitter_context* ucl_object_emit_streamline_new (
+ const ucl_object_t *obj, enum ucl_emitter emit_type,
+ struct ucl_emitter_functions *emitter);
+
+/**
+ * Start object or array container for the streamlined output
+ * @param ctx streamlined context
+ * @param obj container object
+ */
+UCL_EXTERN void ucl_object_emit_streamline_start_container (
+ struct ucl_emitter_context *ctx, const ucl_object_t *obj);
+/**
+ * Add a complete UCL object to streamlined output
+ * @param ctx streamlined context
+ * @param obj object to output
+ */
+UCL_EXTERN void ucl_object_emit_streamline_add_object (
+ struct ucl_emitter_context *ctx, const ucl_object_t *obj);
+/**
+ * End previously added container
+ * @param ctx streamlined context
+ */
+UCL_EXTERN void ucl_object_emit_streamline_end_container (
+ struct ucl_emitter_context *ctx);
+/**
+ * Terminate streamlined container finishing all containers in it
+ * @param ctx streamlined context
+ */
+UCL_EXTERN void ucl_object_emit_streamline_finish (
+ struct ucl_emitter_context *ctx);
+
+/**
+ * Returns functions to emit object to memory
+ * @param pmem target pointer (should be freed by caller)
+ * @return emitter functions structure
+ */
+UCL_EXTERN struct ucl_emitter_functions* ucl_object_emit_memory_funcs (
+ void **pmem);
+
+/**
+ * Returns functions to emit object to FILE *
+ * @param fp FILE * object
+ * @return emitter functions structure
+ */
+UCL_EXTERN struct ucl_emitter_functions* ucl_object_emit_file_funcs (
+ FILE *fp);
+/**
+ * Returns functions to emit object to a file descriptor
+ * @param fd file descriptor
+ * @return emitter functions structure
+ */
+UCL_EXTERN struct ucl_emitter_functions* ucl_object_emit_fd_funcs (
+ int fd);
+
+/**
+ * Free emitter functions
+ * @param f pointer to functions
+ */
+UCL_EXTERN void ucl_object_emit_funcs_free (struct ucl_emitter_functions *f);
+
+/** @} */
+
+/**
+ * @defgroup schema Schema functions
+ * These functions are used to validate UCL objects using json schema format
+ *
+ * @{
+ */
+
+/**
+ * Used to define UCL schema error
+ */
+enum ucl_schema_error_code {
+ UCL_SCHEMA_OK = 0, /**< no error */
+ UCL_SCHEMA_TYPE_MISMATCH, /**< type of object is incorrect */
+ UCL_SCHEMA_INVALID_SCHEMA, /**< schema is invalid */
+ UCL_SCHEMA_MISSING_PROPERTY,/**< one or more missing properties */
+ UCL_SCHEMA_CONSTRAINT, /**< constraint found */
+ UCL_SCHEMA_MISSING_DEPENDENCY, /**< missing dependency */
+ UCL_SCHEMA_EXTERNAL_REF_MISSING, /**< cannot fetch external ref */
+ UCL_SCHEMA_EXTERNAL_REF_INVALID, /**< invalid external ref */
+ UCL_SCHEMA_INTERNAL_ERROR, /**< something bad happened */
+ UCL_SCHEMA_UNKNOWN /**< generic error */
+};
+
+/**
+ * Generic ucl schema error
+ */
+struct ucl_schema_error {
+ enum ucl_schema_error_code code; /**< error code */
+ char msg[128]; /**< error message */
+ const ucl_object_t *obj; /**< object where error occurred */
+};
+
+/**
+ * Validate object `obj` using schema object `schema`.
+ * @param schema schema object
+ * @param obj object to validate
+ * @param err error pointer, if this parameter is not NULL and error has been
+ * occurred, then `err` is filled with the exact error definition.
+ * @return true if `obj` is valid using `schema`
+ */
+UCL_EXTERN bool ucl_object_validate (const ucl_object_t *schema,
+ const ucl_object_t *obj, struct ucl_schema_error *err);
+
+/**
+ * Validate object `obj` using schema object `schema` and root schema at `root`.
+ * @param schema schema object
+ * @param obj object to validate
+ * @param root root schema object
+ * @param err error pointer, if this parameter is not NULL and error has been
+ * occurred, then `err` is filled with the exact error definition.
+ * @return true if `obj` is valid using `schema`
+ */
+UCL_EXTERN bool ucl_object_validate_root (const ucl_object_t *schema,
+ const ucl_object_t *obj,
+ const ucl_object_t *root,
+ struct ucl_schema_error *err);
+
+/**
+ * Validate object `obj` using schema object `schema` and root schema at `root`
+ * using some external references provided.
+ * @param schema schema object
+ * @param obj object to validate
+ * @param root root schema object
+ * @param ext_refs external references (might be modified during validation)
+ * @param err error pointer, if this parameter is not NULL and error has been
+ * occurred, then `err` is filled with the exact error definition.
+ * @return true if `obj` is valid using `schema`
+ */
+UCL_EXTERN bool ucl_object_validate_root_ext (const ucl_object_t *schema,
+ const ucl_object_t *obj,
+ const ucl_object_t *root,
+ ucl_object_t *ext_refs,
+ struct ucl_schema_error *err);
+
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif
+/*
+ * XXX: Poorly named API functions, need to replace them with the appropriate
+ * named function. All API functions *must* use naming ucl_object_*. Usage of
+ * ucl_obj* should be avoided.
+ */
+#define ucl_obj_todouble_safe ucl_object_todouble_safe
+#define ucl_obj_todouble ucl_object_todouble
+#define ucl_obj_tostring ucl_object_tostring
+#define ucl_obj_tostring_safe ucl_object_tostring_safe
+#define ucl_obj_tolstring ucl_object_tolstring
+#define ucl_obj_tolstring_safe ucl_object_tolstring_safe
+#define ucl_obj_toint ucl_object_toint
+#define ucl_obj_toint_safe ucl_object_toint_safe
+#define ucl_obj_toboolean ucl_object_toboolean
+#define ucl_obj_toboolean_safe ucl_object_toboolean_safe
+#define ucl_obj_get_key ucl_object_find_key
+#define ucl_obj_get_keyl ucl_object_find_keyl
+#define ucl_obj_unref ucl_object_unref
+#define ucl_obj_ref ucl_object_ref
+#define ucl_obj_free ucl_object_free
+
+#endif /* UCL_H_ */