1
//
2
// Copyright (c) 2011-2019 Canonical Ltd
3
// Copyright (c) 2006-2010 Kirill Simonov
4
//
5
// Permission is hereby granted, free of charge, to any person obtaining a copy of
6
// this software and associated documentation files (the "Software"), to deal in
7
// the Software without restriction, including without limitation the rights to
8
// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
9
// of the Software, and to permit persons to whom the Software is furnished to do
10
// so, subject to the following conditions:
11
//
12
// The above copyright notice and this permission notice shall be included in all
13
// copies or substantial portions of the Software.
14
//
15
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21
// SOFTWARE.
22

23
package yaml
24

25
import (
26
	"fmt"
27
	"io"
28
)
29

30
// The version directive data.
31
type yaml_version_directive_t struct {
32
	major int8 // The major version number.
33
	minor int8 // The minor version number.
34
}
35

36
// The tag directive data.
37
type yaml_tag_directive_t struct {
38
	handle []byte // The tag handle.
39
	prefix []byte // The tag prefix.
40
}
41

42
type yaml_encoding_t int
43

44
// The stream encoding.
45
const (
46
	// Let the parser choose the encoding.
47
	yaml_ANY_ENCODING yaml_encoding_t = iota
48

49
	yaml_UTF8_ENCODING    // The default UTF-8 encoding.
50
	yaml_UTF16LE_ENCODING // The UTF-16-LE encoding with BOM.
51
	yaml_UTF16BE_ENCODING // The UTF-16-BE encoding with BOM.
52
)
53

54
type yaml_break_t int
55

56
// Line break types.
57
const (
58
	// Let the parser choose the break type.
59
	yaml_ANY_BREAK yaml_break_t = iota
60

61
	yaml_CR_BREAK   // Use CR for line breaks (Mac style).
62
	yaml_LN_BREAK   // Use LN for line breaks (Unix style).
63
	yaml_CRLN_BREAK // Use CR LN for line breaks (DOS style).
64
)
65

66
type yaml_error_type_t int
67

68
// Many bad things could happen with the parser and emitter.
69
const (
70
	// No error is produced.
71
	yaml_NO_ERROR yaml_error_type_t = iota
72

73
	yaml_MEMORY_ERROR   // Cannot allocate or reallocate a block of memory.
74
	yaml_READER_ERROR   // Cannot read or decode the input stream.
75
	yaml_SCANNER_ERROR  // Cannot scan the input stream.
76
	yaml_PARSER_ERROR   // Cannot parse the input stream.
77
	yaml_COMPOSER_ERROR // Cannot compose a YAML document.
78
	yaml_WRITER_ERROR   // Cannot write to the output stream.
79
	yaml_EMITTER_ERROR  // Cannot emit a YAML stream.
80
)
81

82
// The pointer position.
83
type yaml_mark_t struct {
84
	index  int // The position index.
85
	line   int // The position line.
86
	column int // The position column.
87
}
88

89
// Node Styles
90

91
type yaml_style_t int8
92

93
type yaml_scalar_style_t yaml_style_t
94

95
// Scalar styles.
96
const (
97
	// Let the emitter choose the style.
98
	yaml_ANY_SCALAR_STYLE yaml_scalar_style_t = 0
99

100
	yaml_PLAIN_SCALAR_STYLE         yaml_scalar_style_t = 1 << iota // The plain scalar style.
101
	yaml_SINGLE_QUOTED_SCALAR_STYLE                                 // The single-quoted scalar style.
102
	yaml_DOUBLE_QUOTED_SCALAR_STYLE                                 // The double-quoted scalar style.
103
	yaml_LITERAL_SCALAR_STYLE                                       // The literal scalar style.
104
	yaml_FOLDED_SCALAR_STYLE                                        // The folded scalar style.
105
)
106

107
type yaml_sequence_style_t yaml_style_t
108

109
// Sequence styles.
110
const (
111
	// Let the emitter choose the style.
112
	yaml_ANY_SEQUENCE_STYLE yaml_sequence_style_t = iota
113

114
	yaml_BLOCK_SEQUENCE_STYLE // The block sequence style.
115
	yaml_FLOW_SEQUENCE_STYLE  // The flow sequence style.
116
)
117

118
type yaml_mapping_style_t yaml_style_t
119

120
// Mapping styles.
121
const (
122
	// Let the emitter choose the style.
123
	yaml_ANY_MAPPING_STYLE yaml_mapping_style_t = iota
124

125
	yaml_BLOCK_MAPPING_STYLE // The block mapping style.
126
	yaml_FLOW_MAPPING_STYLE  // The flow mapping style.
127
)
128

129
// Tokens
130

131
type yaml_token_type_t int
132

133
// Token types.
134
const (
135
	// An empty token.
136
	yaml_NO_TOKEN yaml_token_type_t = iota
137

138
	yaml_STREAM_START_TOKEN // A STREAM-START token.
139
	yaml_STREAM_END_TOKEN   // A STREAM-END token.
140

141
	yaml_VERSION_DIRECTIVE_TOKEN // A VERSION-DIRECTIVE token.
142
	yaml_TAG_DIRECTIVE_TOKEN     // A TAG-DIRECTIVE token.
143
	yaml_DOCUMENT_START_TOKEN    // A DOCUMENT-START token.
144
	yaml_DOCUMENT_END_TOKEN      // A DOCUMENT-END token.
145

146
	yaml_BLOCK_SEQUENCE_START_TOKEN // A BLOCK-SEQUENCE-START token.
147
	yaml_BLOCK_MAPPING_START_TOKEN  // A BLOCK-SEQUENCE-END token.
148
	yaml_BLOCK_END_TOKEN            // A BLOCK-END token.
149

150
	yaml_FLOW_SEQUENCE_START_TOKEN // A FLOW-SEQUENCE-START token.
151
	yaml_FLOW_SEQUENCE_END_TOKEN   // A FLOW-SEQUENCE-END token.
152
	yaml_FLOW_MAPPING_START_TOKEN  // A FLOW-MAPPING-START token.
153
	yaml_FLOW_MAPPING_END_TOKEN    // A FLOW-MAPPING-END token.
154

155
	yaml_BLOCK_ENTRY_TOKEN // A BLOCK-ENTRY token.
156
	yaml_FLOW_ENTRY_TOKEN  // A FLOW-ENTRY token.
157
	yaml_KEY_TOKEN         // A KEY token.
158
	yaml_VALUE_TOKEN       // A VALUE token.
159

160
	yaml_ALIAS_TOKEN  // An ALIAS token.
161
	yaml_ANCHOR_TOKEN // An ANCHOR token.
162
	yaml_TAG_TOKEN    // A TAG token.
163
	yaml_SCALAR_TOKEN // A SCALAR token.
164
)
165

166
func (tt yaml_token_type_t) String() string {
167
	switch tt {
168
	case yaml_NO_TOKEN:
169
		return "yaml_NO_TOKEN"
170
	case yaml_STREAM_START_TOKEN:
171
		return "yaml_STREAM_START_TOKEN"
172
	case yaml_STREAM_END_TOKEN:
173
		return "yaml_STREAM_END_TOKEN"
174
	case yaml_VERSION_DIRECTIVE_TOKEN:
175
		return "yaml_VERSION_DIRECTIVE_TOKEN"
176
	case yaml_TAG_DIRECTIVE_TOKEN:
177
		return "yaml_TAG_DIRECTIVE_TOKEN"
178
	case yaml_DOCUMENT_START_TOKEN:
179
		return "yaml_DOCUMENT_START_TOKEN"
180
	case yaml_DOCUMENT_END_TOKEN:
181
		return "yaml_DOCUMENT_END_TOKEN"
182
	case yaml_BLOCK_SEQUENCE_START_TOKEN:
183
		return "yaml_BLOCK_SEQUENCE_START_TOKEN"
184
	case yaml_BLOCK_MAPPING_START_TOKEN:
185
		return "yaml_BLOCK_MAPPING_START_TOKEN"
186
	case yaml_BLOCK_END_TOKEN:
187
		return "yaml_BLOCK_END_TOKEN"
188
	case yaml_FLOW_SEQUENCE_START_TOKEN:
189
		return "yaml_FLOW_SEQUENCE_START_TOKEN"
190
	case yaml_FLOW_SEQUENCE_END_TOKEN:
191
		return "yaml_FLOW_SEQUENCE_END_TOKEN"
192
	case yaml_FLOW_MAPPING_START_TOKEN:
193
		return "yaml_FLOW_MAPPING_START_TOKEN"
194
	case yaml_FLOW_MAPPING_END_TOKEN:
195
		return "yaml_FLOW_MAPPING_END_TOKEN"
196
	case yaml_BLOCK_ENTRY_TOKEN:
197
		return "yaml_BLOCK_ENTRY_TOKEN"
198
	case yaml_FLOW_ENTRY_TOKEN:
199
		return "yaml_FLOW_ENTRY_TOKEN"
200
	case yaml_KEY_TOKEN:
201
		return "yaml_KEY_TOKEN"
202
	case yaml_VALUE_TOKEN:
203
		return "yaml_VALUE_TOKEN"
204
	case yaml_ALIAS_TOKEN:
205
		return "yaml_ALIAS_TOKEN"
206
	case yaml_ANCHOR_TOKEN:
207
		return "yaml_ANCHOR_TOKEN"
208
	case yaml_TAG_TOKEN:
209
		return "yaml_TAG_TOKEN"
210
	case yaml_SCALAR_TOKEN:
211
		return "yaml_SCALAR_TOKEN"
212
	}
213
	return "<unknown token>"
214
}
215

216
// The token structure.
217
type yaml_token_t struct {
218
	// The token type.
219
	typ yaml_token_type_t
220

221
	// The start/end of the token.
222
	start_mark, end_mark yaml_mark_t
223

224
	// The stream encoding (for yaml_STREAM_START_TOKEN).
225
	encoding yaml_encoding_t
226

227
	// The alias/anchor/scalar value or tag/tag directive handle
228
	// (for yaml_ALIAS_TOKEN, yaml_ANCHOR_TOKEN, yaml_SCALAR_TOKEN, yaml_TAG_TOKEN, yaml_TAG_DIRECTIVE_TOKEN).
229
	value []byte
230

231
	// The tag suffix (for yaml_TAG_TOKEN).
232
	suffix []byte
233

234
	// The tag directive prefix (for yaml_TAG_DIRECTIVE_TOKEN).
235
	prefix []byte
236

237
	// The scalar style (for yaml_SCALAR_TOKEN).
238
	style yaml_scalar_style_t
239

240
	// The version directive major/minor (for yaml_VERSION_DIRECTIVE_TOKEN).
241
	major, minor int8
242
}
243

244
// Events
245

246
type yaml_event_type_t int8
247

248
// Event types.
249
const (
250
	// An empty event.
251
	yaml_NO_EVENT yaml_event_type_t = iota
252

253
	yaml_STREAM_START_EVENT   // A STREAM-START event.
254
	yaml_STREAM_END_EVENT     // A STREAM-END event.
255
	yaml_DOCUMENT_START_EVENT // A DOCUMENT-START event.
256
	yaml_DOCUMENT_END_EVENT   // A DOCUMENT-END event.
257
	yaml_ALIAS_EVENT          // An ALIAS event.
258
	yaml_SCALAR_EVENT         // A SCALAR event.
259
	yaml_SEQUENCE_START_EVENT // A SEQUENCE-START event.
260
	yaml_SEQUENCE_END_EVENT   // A SEQUENCE-END event.
261
	yaml_MAPPING_START_EVENT  // A MAPPING-START event.
262
	yaml_MAPPING_END_EVENT    // A MAPPING-END event.
263
	yaml_TAIL_COMMENT_EVENT
264
)
265

266
var eventStrings = []string{
267
	yaml_NO_EVENT:             "none",
268
	yaml_STREAM_START_EVENT:   "stream start",
269
	yaml_STREAM_END_EVENT:     "stream end",
270
	yaml_DOCUMENT_START_EVENT: "document start",
271
	yaml_DOCUMENT_END_EVENT:   "document end",
272
	yaml_ALIAS_EVENT:          "alias",
273
	yaml_SCALAR_EVENT:         "scalar",
274
	yaml_SEQUENCE_START_EVENT: "sequence start",
275
	yaml_SEQUENCE_END_EVENT:   "sequence end",
276
	yaml_MAPPING_START_EVENT:  "mapping start",
277
	yaml_MAPPING_END_EVENT:    "mapping end",
278
	yaml_TAIL_COMMENT_EVENT:   "tail comment",
279
}
280

281
func (e yaml_event_type_t) String() string {
282
	if e < 0 || int(e) >= len(eventStrings) {
283
		return fmt.Sprintf("unknown event %d", e)
284
	}
285
	return eventStrings[e]
286
}
287

288
// The event structure.
289
type yaml_event_t struct {
290

291
	// The event type.
292
	typ yaml_event_type_t
293

294
	// The start and end of the event.
295
	start_mark, end_mark yaml_mark_t
296

297
	// The document encoding (for yaml_STREAM_START_EVENT).
298
	encoding yaml_encoding_t
299

300
	// The version directive (for yaml_DOCUMENT_START_EVENT).
301
	version_directive *yaml_version_directive_t
302

303
	// The list of tag directives (for yaml_DOCUMENT_START_EVENT).
304
	tag_directives []yaml_tag_directive_t
305

306
	// The comments
307
	head_comment []byte
308
	line_comment []byte
309
	foot_comment []byte
310
	tail_comment []byte
311

312
	// The anchor (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT, yaml_ALIAS_EVENT).
313
	anchor []byte
314

315
	// The tag (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT).
316
	tag []byte
317

318
	// The scalar value (for yaml_SCALAR_EVENT).
319
	value []byte
320

321
	// Is the document start/end indicator implicit, or the tag optional?
322
	// (for yaml_DOCUMENT_START_EVENT, yaml_DOCUMENT_END_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT, yaml_SCALAR_EVENT).
323
	implicit bool
324

325
	// Is the tag optional for any non-plain style? (for yaml_SCALAR_EVENT).
326
	quoted_implicit bool
327

328
	// The style (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT).
329
	style yaml_style_t
330
}
331

332
func (e *yaml_event_t) scalar_style() yaml_scalar_style_t     { return yaml_scalar_style_t(e.style) }
333
func (e *yaml_event_t) sequence_style() yaml_sequence_style_t { return yaml_sequence_style_t(e.style) }
334
func (e *yaml_event_t) mapping_style() yaml_mapping_style_t   { return yaml_mapping_style_t(e.style) }
335

336
// Nodes
337

338
const (
339
	yaml_NULL_TAG      = "tag:yaml.org,2002:null"      // The tag !!null with the only possible value: null.
340
	yaml_BOOL_TAG      = "tag:yaml.org,2002:bool"      // The tag !!bool with the values: true and false.
341
	yaml_STR_TAG       = "tag:yaml.org,2002:str"       // The tag !!str for string values.
342
	yaml_INT_TAG       = "tag:yaml.org,2002:int"       // The tag !!int for integer values.
343
	yaml_FLOAT_TAG     = "tag:yaml.org,2002:float"     // The tag !!float for float values.
344
	yaml_TIMESTAMP_TAG = "tag:yaml.org,2002:timestamp" // The tag !!timestamp for date and time values.
345

346
	yaml_SEQ_TAG = "tag:yaml.org,2002:seq" // The tag !!seq is used to denote sequences.
347
	yaml_MAP_TAG = "tag:yaml.org,2002:map" // The tag !!map is used to denote mapping.
348

349
	// Not in original libyaml.
350
	yaml_BINARY_TAG = "tag:yaml.org,2002:binary"
351
	yaml_MERGE_TAG  = "tag:yaml.org,2002:merge"
352

353
	yaml_DEFAULT_SCALAR_TAG   = yaml_STR_TAG // The default scalar tag is !!str.
354
	yaml_DEFAULT_SEQUENCE_TAG = yaml_SEQ_TAG // The default sequence tag is !!seq.
355
	yaml_DEFAULT_MAPPING_TAG  = yaml_MAP_TAG // The default mapping tag is !!map.
356
)
357

358
type yaml_node_type_t int
359

360
// Node types.
361
const (
362
	// An empty node.
363
	yaml_NO_NODE yaml_node_type_t = iota
364

365
	yaml_SCALAR_NODE   // A scalar node.
366
	yaml_SEQUENCE_NODE // A sequence node.
367
	yaml_MAPPING_NODE  // A mapping node.
368
)
369

370
// An element of a sequence node.
371
type yaml_node_item_t int
372

373
// An element of a mapping node.
374
type yaml_node_pair_t struct {
375
	key   int // The key of the element.
376
	value int // The value of the element.
377
}
378

379
// The node structure.
380
type yaml_node_t struct {
381
	typ yaml_node_type_t // The node type.
382
	tag []byte           // The node tag.
383

384
	// The node data.
385

386
	// The scalar parameters (for yaml_SCALAR_NODE).
387
	scalar struct {
388
		value  []byte              // The scalar value.
389
		length int                 // The length of the scalar value.
390
		style  yaml_scalar_style_t // The scalar style.
391
	}
392

393
	// The sequence parameters (for YAML_SEQUENCE_NODE).
394
	sequence struct {
395
		items_data []yaml_node_item_t    // The stack of sequence items.
396
		style      yaml_sequence_style_t // The sequence style.
397
	}
398

399
	// The mapping parameters (for yaml_MAPPING_NODE).
400
	mapping struct {
401
		pairs_data  []yaml_node_pair_t   // The stack of mapping pairs (key, value).
402
		pairs_start *yaml_node_pair_t    // The beginning of the stack.
403
		pairs_end   *yaml_node_pair_t    // The end of the stack.
404
		pairs_top   *yaml_node_pair_t    // The top of the stack.
405
		style       yaml_mapping_style_t // The mapping style.
406
	}
407

408
	start_mark yaml_mark_t // The beginning of the node.
409
	end_mark   yaml_mark_t // The end of the node.
410

411
}
412

413
// The document structure.
414
type yaml_document_t struct {
415

416
	// The document nodes.
417
	nodes []yaml_node_t
418

419
	// The version directive.
420
	version_directive *yaml_version_directive_t
421

422
	// The list of tag directives.
423
	tag_directives_data  []yaml_tag_directive_t
424
	tag_directives_start int // The beginning of the tag directives list.
425
	tag_directives_end   int // The end of the tag directives list.
426

427
	start_implicit int // Is the document start indicator implicit?
428
	end_implicit   int // Is the document end indicator implicit?
429

430
	// The start/end of the document.
431
	start_mark, end_mark yaml_mark_t
432
}
433

434
// The prototype of a read handler.
435
//
436
// The read handler is called when the parser needs to read more bytes from the
437
// source. The handler should write not more than size bytes to the buffer.
438
// The number of written bytes should be set to the size_read variable.
439
//
440
// [in,out]   data        A pointer to an application data specified by
441
//                        yaml_parser_set_input().
442
// [out]      buffer      The buffer to write the data from the source.
443
// [in]       size        The size of the buffer.
444
// [out]      size_read   The actual number of bytes read from the source.
445
//
446
// On success, the handler should return 1.  If the handler failed,
447
// the returned value should be 0. On EOF, the handler should set the
448
// size_read to 0 and return 1.
449
type yaml_read_handler_t func(parser *yaml_parser_t, buffer []byte) (n int, err error)
450

451
// This structure holds information about a potential simple key.
452
type yaml_simple_key_t struct {
453
	possible     bool        // Is a simple key possible?
454
	required     bool        // Is a simple key required?
455
	token_number int         // The number of the token.
456
	mark         yaml_mark_t // The position mark.
457
}
458

459
// The states of the parser.
460
type yaml_parser_state_t int
461

462
const (
463
	yaml_PARSE_STREAM_START_STATE yaml_parser_state_t = iota
464

465
	yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE           // Expect the beginning of an implicit document.
466
	yaml_PARSE_DOCUMENT_START_STATE                    // Expect DOCUMENT-START.
467
	yaml_PARSE_DOCUMENT_CONTENT_STATE                  // Expect the content of a document.
468
	yaml_PARSE_DOCUMENT_END_STATE                      // Expect DOCUMENT-END.
469
	yaml_PARSE_BLOCK_NODE_STATE                        // Expect a block node.
470
	yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE // Expect a block node or indentless sequence.
471
	yaml_PARSE_FLOW_NODE_STATE                         // Expect a flow node.
472
	yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE        // Expect the first entry of a block sequence.
473
	yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE              // Expect an entry of a block sequence.
474
	yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE         // Expect an entry of an indentless sequence.
475
	yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE           // Expect the first key of a block mapping.
476
	yaml_PARSE_BLOCK_MAPPING_KEY_STATE                 // Expect a block mapping key.
477
	yaml_PARSE_BLOCK_MAPPING_VALUE_STATE               // Expect a block mapping value.
478
	yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE         // Expect the first entry of a flow sequence.
479
	yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE               // Expect an entry of a flow sequence.
480
	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE   // Expect a key of an ordered mapping.
481
	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE // Expect a value of an ordered mapping.
482
	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE   // Expect the and of an ordered mapping entry.
483
	yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE            // Expect the first key of a flow mapping.
484
	yaml_PARSE_FLOW_MAPPING_KEY_STATE                  // Expect a key of a flow mapping.
485
	yaml_PARSE_FLOW_MAPPING_VALUE_STATE                // Expect a value of a flow mapping.
486
	yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE          // Expect an empty value of a flow mapping.
487
	yaml_PARSE_END_STATE                               // Expect nothing.
488
)
489

490
func (ps yaml_parser_state_t) String() string {
491
	switch ps {
492
	case yaml_PARSE_STREAM_START_STATE:
493
		return "yaml_PARSE_STREAM_START_STATE"
494
	case yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE:
495
		return "yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE"
496
	case yaml_PARSE_DOCUMENT_START_STATE:
497
		return "yaml_PARSE_DOCUMENT_START_STATE"
498
	case yaml_PARSE_DOCUMENT_CONTENT_STATE:
499
		return "yaml_PARSE_DOCUMENT_CONTENT_STATE"
500
	case yaml_PARSE_DOCUMENT_END_STATE:
501
		return "yaml_PARSE_DOCUMENT_END_STATE"
502
	case yaml_PARSE_BLOCK_NODE_STATE:
503
		return "yaml_PARSE_BLOCK_NODE_STATE"
504
	case yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE:
505
		return "yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE"
506
	case yaml_PARSE_FLOW_NODE_STATE:
507
		return "yaml_PARSE_FLOW_NODE_STATE"
508
	case yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE:
509
		return "yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE"
510
	case yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE:
511
		return "yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE"
512
	case yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE:
513
		return "yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE"
514
	case yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE:
515
		return "yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE"
516
	case yaml_PARSE_BLOCK_MAPPING_KEY_STATE:
517
		return "yaml_PARSE_BLOCK_MAPPING_KEY_STATE"
518
	case yaml_PARSE_BLOCK_MAPPING_VALUE_STATE:
519
		return "yaml_PARSE_BLOCK_MAPPING_VALUE_STATE"
520
	case yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE:
521
		return "yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE"
522
	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE:
523
		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE"
524
	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE:
525
		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE"
526
	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE:
527
		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE"
528
	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE:
529
		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE"
530
	case yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE:
531
		return "yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE"
532
	case yaml_PARSE_FLOW_MAPPING_KEY_STATE:
533
		return "yaml_PARSE_FLOW_MAPPING_KEY_STATE"
534
	case yaml_PARSE_FLOW_MAPPING_VALUE_STATE:
535
		return "yaml_PARSE_FLOW_MAPPING_VALUE_STATE"
536
	case yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE:
537
		return "yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE"
538
	case yaml_PARSE_END_STATE:
539
		return "yaml_PARSE_END_STATE"
540
	}
541
	return "<unknown parser state>"
542
}
543

544
// This structure holds aliases data.
545
type yaml_alias_data_t struct {
546
	anchor []byte      // The anchor.
547
	index  int         // The node id.
548
	mark   yaml_mark_t // The anchor mark.
549
}
550

551
// The parser structure.
552
//
553
// All members are internal. Manage the structure using the
554
// yaml_parser_ family of functions.
555
type yaml_parser_t struct {
556

557
	// Error handling
558

559
	error yaml_error_type_t // Error type.
560

561
	problem string // Error description.
562

563
	// The byte about which the problem occurred.
564
	problem_offset int
565
	problem_value  int
566
	problem_mark   yaml_mark_t
567

568
	// The error context.
569
	context      string
570
	context_mark yaml_mark_t
571

572
	// Reader stuff
573

574
	read_handler yaml_read_handler_t // Read handler.
575

576
	input_reader io.Reader // File input data.
577
	input        []byte    // String input data.
578
	input_pos    int
579

580
	eof bool // EOF flag
581

582
	buffer     []byte // The working buffer.
583
	buffer_pos int    // The current position of the buffer.
584

585
	unread int // The number of unread characters in the buffer.
586

587
	newlines int // The number of line breaks since last non-break/non-blank character
588

589
	raw_buffer     []byte // The raw buffer.
590
	raw_buffer_pos int    // The current position of the buffer.
591

592
	encoding yaml_encoding_t // The input encoding.
593

594
	offset int         // The offset of the current position (in bytes).
595
	mark   yaml_mark_t // The mark of the current position.
596

597
	// Comments
598

599
	head_comment []byte // The current head comments
600
	line_comment []byte // The current line comments
601
	foot_comment []byte // The current foot comments
602
	tail_comment []byte // Foot comment that happens at the end of a block.
603
	stem_comment []byte // Comment in item preceding a nested structure (list inside list item, etc)
604

605
	comments      []yaml_comment_t // The folded comments for all parsed tokens
606
	comments_head int
607

608
	// Scanner stuff
609

610
	stream_start_produced bool // Have we started to scan the input stream?
611
	stream_end_produced   bool // Have we reached the end of the input stream?
612

613
	flow_level int // The number of unclosed '[' and '{' indicators.
614

615
	tokens          []yaml_token_t // The tokens queue.
616
	tokens_head     int            // The head of the tokens queue.
617
	tokens_parsed   int            // The number of tokens fetched from the queue.
618
	token_available bool           // Does the tokens queue contain a token ready for dequeueing.
619

620
	indent  int   // The current indentation level.
621
	indents []int // The indentation levels stack.
622

623
	simple_key_allowed bool                // May a simple key occur at the current position?
624
	simple_keys        []yaml_simple_key_t // The stack of simple keys.
625
	simple_keys_by_tok map[int]int         // possible simple_key indexes indexed by token_number
626

627
	// Parser stuff
628

629
	state          yaml_parser_state_t    // The current parser state.
630
	states         []yaml_parser_state_t  // The parser states stack.
631
	marks          []yaml_mark_t          // The stack of marks.
632
	tag_directives []yaml_tag_directive_t // The list of TAG directives.
633

634
	// Dumper stuff
635

636
	aliases []yaml_alias_data_t // The alias data.
637

638
	document *yaml_document_t // The currently parsed document.
639
}
640

641
type yaml_comment_t struct {
642

643
	scan_mark  yaml_mark_t // Position where scanning for comments started
644
	token_mark yaml_mark_t // Position after which tokens will be associated with this comment
645
	start_mark yaml_mark_t // Position of '#' comment mark
646
	end_mark   yaml_mark_t // Position where comment terminated
647

648
	head []byte
649
	line []byte
650
	foot []byte
651
}
652

653
// Emitter Definitions
654

655
// The prototype of a write handler.
656
//
657
// The write handler is called when the emitter needs to flush the accumulated
658
// characters to the output.  The handler should write @a size bytes of the
659
// @a buffer to the output.
660
//
661
// @param[in,out]   data        A pointer to an application data specified by
662
//                              yaml_emitter_set_output().
663
// @param[in]       buffer      The buffer with bytes to be written.
664
// @param[in]       size        The size of the buffer.
665
//
666
// @returns On success, the handler should return @c 1.  If the handler failed,
667
// the returned value should be @c 0.
668
//
669
type yaml_write_handler_t func(emitter *yaml_emitter_t, buffer []byte) error
670

671
type yaml_emitter_state_t int
672

673
// The emitter states.
674
const (
675
	// Expect STREAM-START.
676
	yaml_EMIT_STREAM_START_STATE yaml_emitter_state_t = iota
677

678
	yaml_EMIT_FIRST_DOCUMENT_START_STATE       // Expect the first DOCUMENT-START or STREAM-END.
679
	yaml_EMIT_DOCUMENT_START_STATE             // Expect DOCUMENT-START or STREAM-END.
680
	yaml_EMIT_DOCUMENT_CONTENT_STATE           // Expect the content of a document.
681
	yaml_EMIT_DOCUMENT_END_STATE               // Expect DOCUMENT-END.
682
	yaml_EMIT_FLOW_SEQUENCE_FIRST_ITEM_STATE   // Expect the first item of a flow sequence.
683
	yaml_EMIT_FLOW_SEQUENCE_TRAIL_ITEM_STATE   // Expect the next item of a flow sequence, with the comma already written out
684
	yaml_EMIT_FLOW_SEQUENCE_ITEM_STATE         // Expect an item of a flow sequence.
685
	yaml_EMIT_FLOW_MAPPING_FIRST_KEY_STATE     // Expect the first key of a flow mapping.
686
	yaml_EMIT_FLOW_MAPPING_TRAIL_KEY_STATE     // Expect the next key of a flow mapping, with the comma already written out
687
	yaml_EMIT_FLOW_MAPPING_KEY_STATE           // Expect a key of a flow mapping.
688
	yaml_EMIT_FLOW_MAPPING_SIMPLE_VALUE_STATE  // Expect a value for a simple key of a flow mapping.
689
	yaml_EMIT_FLOW_MAPPING_VALUE_STATE         // Expect a value of a flow mapping.
690
	yaml_EMIT_BLOCK_SEQUENCE_FIRST_ITEM_STATE  // Expect the first item of a block sequence.
691
	yaml_EMIT_BLOCK_SEQUENCE_ITEM_STATE        // Expect an item of a block sequence.
692
	yaml_EMIT_BLOCK_MAPPING_FIRST_KEY_STATE    // Expect the first key of a block mapping.
693
	yaml_EMIT_BLOCK_MAPPING_KEY_STATE          // Expect the key of a block mapping.
694
	yaml_EMIT_BLOCK_MAPPING_SIMPLE_VALUE_STATE // Expect a value for a simple key of a block mapping.
695
	yaml_EMIT_BLOCK_MAPPING_VALUE_STATE        // Expect a value of a block mapping.
696
	yaml_EMIT_END_STATE                        // Expect nothing.
697
)
698

699
// The emitter structure.
700
//
701
// All members are internal.  Manage the structure using the @c yaml_emitter_
702
// family of functions.
703
type yaml_emitter_t struct {
704

705
	// Error handling
706

707
	error   yaml_error_type_t // Error type.
708
	problem string            // Error description.
709

710
	// Writer stuff
711

712
	write_handler yaml_write_handler_t // Write handler.
713

714
	output_buffer *[]byte   // String output data.
715
	output_writer io.Writer // File output data.
716

717
	buffer     []byte // The working buffer.
718
	buffer_pos int    // The current position of the buffer.
719

720
	raw_buffer     []byte // The raw buffer.
721
	raw_buffer_pos int    // The current position of the buffer.
722

723
	encoding yaml_encoding_t // The stream encoding.
724

725
	// Emitter stuff
726

727
	canonical   bool         // If the output is in the canonical style?
728
	best_indent int          // The number of indentation spaces.
729
	best_width  int          // The preferred width of the output lines.
730
	unicode     bool         // Allow unescaped non-ASCII characters?
731
	line_break  yaml_break_t // The preferred line break.
732

733
	state  yaml_emitter_state_t   // The current emitter state.
734
	states []yaml_emitter_state_t // The stack of states.
735

736
	events      []yaml_event_t // The event queue.
737
	events_head int            // The head of the event queue.
738

739
	indents []int // The stack of indentation levels.
740

741
	tag_directives []yaml_tag_directive_t // The list of tag directives.
742

743
	indent int // The current indentation level.
744

745
	flow_level int // The current flow level.
746

747
	root_context       bool // Is it the document root context?
748
	sequence_context   bool // Is it a sequence context?
749
	mapping_context    bool // Is it a mapping context?
750
	simple_key_context bool // Is it a simple mapping key context?
751

752
	line       int  // The current line.
753
	column     int  // The current column.
754
	whitespace bool // If the last character was a whitespace?
755
	indention  bool // If the last character was an indentation character (' ', '-', '?', ':')?
756
	open_ended bool // If an explicit document end is required?
757

758
	space_above bool // Is there's an empty line above?
759
	foot_indent int  // The indent used to write the foot comment above, or -1 if none.
760

761
	// Anchor analysis.
762
	anchor_data struct {
763
		anchor []byte // The anchor value.
764
		alias  bool   // Is it an alias?
765
	}
766

767
	// Tag analysis.
768
	tag_data struct {
769
		handle []byte // The tag handle.
770
		suffix []byte // The tag suffix.
771
	}
772

773
	// Scalar analysis.
774
	scalar_data struct {
775
		value                 []byte              // The scalar value.
776
		multiline             bool                // Does the scalar contain line breaks?
777
		flow_plain_allowed    bool                // Can the scalar be expessed in the flow plain style?
778
		block_plain_allowed   bool                // Can the scalar be expressed in the block plain style?
779
		single_quoted_allowed bool                // Can the scalar be expressed in the single quoted style?
780
		block_allowed         bool                // Can the scalar be expressed in the literal or folded styles?
781
		style                 yaml_scalar_style_t // The output style.
782
	}
783

784
	// Comments
785
	head_comment []byte
786
	line_comment []byte
787
	foot_comment []byte
788
	tail_comment []byte
789

790
	key_line_comment []byte
791

792
	// Dumper stuff
793

794
	opened bool // If the stream was already opened?
795
	closed bool // If the stream was already closed?
796

797
	// The information associated with the document nodes.
798
	anchors *struct {
799
		references int  // The number of references.
800
		anchor     int  // The anchor id.
801
		serialized bool // If the node has been emitted?
802
	}
803

804
	last_anchor_id int // The last assigned anchor id.
805

806
	document *yaml_document_t // The currently emitted document.
807
}
808

809