aboutsummaryrefslogtreecommitdiff
path: root/include/ucl.h
blob: 3eeea9a7df0e2aedd32f2523067115948daf6cd1 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
/* Copyright (c) 2013, 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_EMACRO, /**< Error processing a macro */
	UCL_EINTERNAL, /**< Internal unclassified error */
	UCL_ESSL /**< SSL error */
} 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_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_KEY_LOWERCASE = 0x1, /**< Convert all keys to lower case */
	UCL_PARSER_ZEROCOPY = 0x2, /**< Parse input in zero-copy mode if possible */
	UCL_PARSER_NO_TIME = 0x4 /**< Do not parse time and treat time values as strings */
} ucl_parser_flags_t;

/**
 * String conversion flags, that are used in #ucl_object_fromstring_common function.
 */
typedef enum ucl_string_flags {
	UCL_STRING_ESCAPE = 0x1,  /**< Perform JSON escape */
	UCL_STRING_TRIM = 0x2,    /**< Trim leading and trailing whitespaces */
	UCL_STRING_PARSE_BOOLEAN = 0x4,    /**< Parse passed string and detect boolean */
	UCL_STRING_PARSE_INT = 0x8,    /**< Parse passed string and detect integer number */
	UCL_STRING_PARSE_DOUBLE = 0x10,    /**< Parse passed string and detect integer or float number */
	UCL_STRING_PARSE_TIME = 0x20, /**< 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 = 0x40  /**< Treat numbers as bytes */
} ucl_string_flags_t;

/**
 * Basic flags for an object
 */
typedef enum ucl_object_flags {
	UCL_OBJECT_ALLOCATED_KEY = 1, /**< An object has key allocated internally */
	UCL_OBJECT_ALLOCATED_VALUE = 2, /**< An object has a string value allocated internally */
	UCL_OBJECT_NEED_KEY_ESCAPE = 4 /**< The key of an object need to be escaped on output */
} ucl_object_flags_t;

/**
 * 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 */
		struct ucl_object_s *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			*/
	unsigned char* trash_stack[2];			/**< Pointer to allocated chunks */
	unsigned keylen;						/**< Lenght of a key		*/
	unsigned len;							/**< Size of an object		*/
	enum ucl_type type;						/**< Real type				*/
	uint16_t ref;							/**< Reference count		*/
	uint16_t flags;							/**< Object flags			*/
} ucl_object_t;

/** @} */

/**
 * @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;

/**
 * Return the type of an object
 * @return the object type
 */
UCL_EXTERN ucl_type_t ucl_object_type (const ucl_object_t *obj);

/**
 * 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 (will be created automatically if top is NULL)
 * @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 (will be created automatically if top is NULL)
 * @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);

/**
 * 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);


/**
 * Delete key from `top` object returning the object deleted. This object is not
 * released
 * @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;

/**
 * Delete key from `top` object returning the object deleted. This object is not
 * released
 * @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 (will be created automatically if top is NULL)
 * @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);

/**
 * Append an element to the front of array object
 * @param top destination object (will be created automatically if top is 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 (will be created automatically if top is 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);

/**
 * Removes an element `elt` from the array `top`. Caller must unref the returned object when it is not
 * 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`. Caller must unref the returned object when it is not
 * 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);

/**
 * Return object identified by an index of the array `top`
 * @param obj object to get a key from (must be of type UCL_ARRAY)
 * @param index 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);

/**
 * Removes the first element from the array `top`. Caller must unref the returned object when it is not
 * 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);

/**
 * Append a element to another element forming an implicit array
 * @param head head to append (may be NULL)
 * @param elt new element
 * @return true if element has been inserted
 */
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 matched the specified key or NULL if key is not found
 */
UCL_EXTERN const ucl_object_t* ucl_object_find_key (const ucl_object_t *obj,
		const char *key);

/**
 * 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 matched the specified key or NULL if key is not found
 */
UCL_EXTERN const ucl_object_t* ucl_object_find_keyl (const ucl_object_t *obj,
		const char *key, size_t klen);

/**
 * 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_lookup_path (const ucl_object_t *obj,
		const char *path);

/**
 * 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
 */
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);

/**
 * 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));

/**
 * 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) ...
 * @return the next object or NULL
 */
UCL_EXTERN const ucl_object_t* ucl_iterate_object (const ucl_object_t *obj,
		ucl_object_iter_t *iter, bool expand_values);
/** @} */


/**
 * @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 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, 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);

/**
 * 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
 */
UCL_EXTERN void ucl_parser_register_macro (struct ucl_parser *parser, const char *macro,
		ucl_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
 * @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_chunk (struct ucl_parser *parser,
		const unsigned 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
 * @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 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 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);

/**
 * 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 error string if failing
 * @param parser parser object
 */
UCL_EXTERN const char *ucl_parser_get_error(struct ucl_parser *parser);
/**
 * Free ucl parser object
 * @param parser parser object
 */
UCL_EXTERN void ucl_parser_free (struct ucl_parser *parser);

/**
 * 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_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);

/** @} */

/**
 * @defgroup emitter Emitting functions
 * These functions are used to serialise UCL objects to some string representation.
 *
 * @{
 */

/**
 * 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);
	/** Opaque userdata pointer */
	void *ud;
};

/**
 * 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
 * @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 bool ucl_object_emit_full (const ucl_object_t *obj,
		enum ucl_emitter emit_type,
		struct ucl_emitter_functions *emitter);
/** @} */

/**
 * @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_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 occured */
};

/**
 * 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
 * occured, 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);

/** @} */

#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_ */