]> git.zerfleddert.de Git - proxmark3-svn/blame - client/tinycbor/cbortojson.c
emv/sc fixes and modifications: (#780)
[proxmark3-svn] / client / tinycbor / cbortojson.c
CommitLineData
0bb51450
OM
1/****************************************************************************
2**
3** Copyright (C) 2018 Intel Corporation
4**
5** Permission is hereby granted, free of charge, to any person obtaining a copy
6** of this software and associated documentation files (the "Software"), to deal
7** in the Software without restriction, including without limitation the rights
8** to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9** copies of the Software, and to permit persons to whom the Software is
10** furnished to do so, subject to the following conditions:
11**
12** The above copyright notice and this permission notice shall be included in
13** all 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
21** THE SOFTWARE.
22**
23****************************************************************************/
24
25#define _BSD_SOURCE 1
26#define _DEFAULT_SOURCE 1
27#define _GNU_SOURCE 1
28#define _POSIX_C_SOURCE 200809L
29#ifndef __STDC_LIMIT_MACROS
30# define __STDC_LIMIT_MACROS 1
31#endif
32
33#include "cbor.h"
34#include "cborjson.h"
35#include "cborinternal_p.h"
36#include "compilersupport_p.h"
37
38#include <inttypes.h>
39#include <stdio.h>
40#include <stdlib.h>
41#include <string.h>
42
43/**
44 * \defgroup CborToJson Converting CBOR to JSON
45 * \brief Group of functions used to convert CBOR to JSON.
46 *
47 * This group contains two functions that can be used to convert a \ref
48 * CborValue object to an equivalent JSON representation. This module attempts
49 * to follow the recommendations from RFC 7049 section 4.1 "Converting from
50 * CBOR to JSON", though it has a few differences. They are noted below.
51 *
52 * These functions produce a "minified" JSON output, with no spacing,
53 * indentation or line breaks. If those are necessary, they need to be applied
54 * in a post-processing phase.
55 *
56 * Note that JSON cannot support all CBOR types with fidelity, so the
57 * conversion is usually lossy. For that reason, TinyCBOR supports adding a set
58 * of metadata JSON values that can be used by a JSON-to-CBOR converter to
59 * restore the original data types.
60 *
61 * The TinyCBOR library does not provide a way to convert from JSON
62 * representation back to encoded form. However, it provides a tool called
63 * \c json2cbor which can be used for that purpose. That tool supports the
64 * metadata format that these functions may produce.
65 *
66 * Either of the functions in this section will attempt to convert exactly one
67 * CborValue object to JSON. Those functions may return any error documented
68 * for the functions for CborParsing. In addition, if the C standard library
69 * stream functions return with error, the text conversion will return with
70 * error CborErrorIO.
71 *
72 * These functions also perform UTF-8 validation in CBOR text strings. If they
73 * encounter a sequence of bytes that is not permitted in UTF-8, they will return
74 * CborErrorInvalidUtf8TextString. That includes encoding of surrogate points
75 * in UTF-8.
76 *
77 * \warning The metadata produced by these functions is not guaranteed to
78 * remain stable. A future update of TinyCBOR may produce different output for
79 * the same input and parsers may be unable to handle it.
80 *
81 * \sa CborParsing, CborPretty, cbor_parser_init()
82 */
83
84/**
85 * \addtogroup CborToJson
86 * @{
87 * <h2 class="groupheader">Conversion limitations</h2>
88 *
89 * When converting from CBOR to JSON, there may be information loss. This
90 * section lists the possible scenarios.
91 *
92 * \par Number precision:
93 * ALL JSON numbers, due to its JavaScript heritage, are IEEE 754
94 * double-precision floating point. This means JSON is not capable of
95 * representing all integers numbers outside the range [-(2<sup>53</sup>)+1,
96 * 2<sup>53</sup>-1] and is not capable of representing NaN or infinite. If the
97 * CBOR data contains a number outside the valid range, the conversion will
98 * lose precision. If the input was NaN or infinite, the result of the
99 * conversion will be the JSON null value. In addition, the distinction between
100 * half-, single- and double-precision is lost.
101 *
102 * \par
103 * If enabled, the original value and original type are stored in the metadata.
104 *
105 * \par Non-native types:
106 * CBOR's type system is richer than JSON's, which means some data values
107 * cannot be represented when converted to JSON. The conversion silently turns
108 * them into strings: CBOR simple types become "simple(nn)" where \c nn is the
109 * simple type's value, with the exception of CBOR undefined, which becomes
110 * "undefined", while CBOR byte strings are converted to an Base16, Base64, or
111 * Base64url encoding
112 *
113 * \par
114 * If enabled, the original type is stored in the metadata.
115 *
116 * \par Presence of tags:
117 * JSON has no support for tagged values, so by default tags are dropped when
118 * converting to JSON. However, if the CborConvertObeyByteStringTags option is
119 * active (default), then certain known tags are honored and are used to format
120 * the conversion of the tagged byte string to JSON.
121 *
122 * \par
123 * If the CborConvertTagsToObjects option is active, then the tag and the
124 * tagged value are converted to a JSON object. Otherwise, if enabled, the
125 * last (innermost) tag is stored in the metadata.
126 *
127 * \par Non-string keys in maps:
128 * JSON requires all Object keys to be strings, while CBOR does not. By
129 * default, if a non-string key is found, the conversion fails with error
130 * CborErrorJsonObjectKeyNotString. If the CborConvertStringifyMapKeys option
131 * is active, then the conversion attempts to create a string representation
132 * using CborPretty. Note that the \c json2cbor tool is not able to parse this
133 * back to the original form.
134 *
135 * \par Duplicate keys in maps:
136 * Neither JSON nor CBOR allow duplicated keys, but current TinyCBOR does not
137 * validate that this is the case. If there are duplicated keys in the input,
138 * they will be repeated in the output, which many JSON tools may flag as
139 * invalid. In addition to that, if the CborConvertStringifyMapKeys option is
140 * active, it is possible that a non-string key in a CBOR map will be converted
141 * to a string form that is identical to another key.
142 *
143 * \par
144 * When metadata support is active, the conversion will add extra key-value
145 * pairs to the JSON output so it can store the metadata. It is possible that
146 * the keys for the metadata clash with existing keys in the JSON map.
147 */
148
149extern FILE *open_memstream(char **bufptr, size_t *sizeptr);
150
151enum ConversionStatusFlags {
152 TypeWasNotNative = 0x100, /* anything but strings, boolean, null, arrays and maps */
153 TypeWasTagged = 0x200,
154 NumberPrecisionWasLost = 0x400,
155 NumberWasNaN = 0x800,
156 NumberWasInfinite = 0x1000,
157 NumberWasNegative = 0x2000, /* only used with NumberWasInifite or NumberWasTooBig */
158
159 FinalTypeMask = 0xff
160};
161
162typedef struct ConversionStatus {
163 CborTag lastTag;
164 uint64_t originalNumber;
165 int flags;
166} ConversionStatus;
167
168static CborError value_to_json(FILE *out, CborValue *it, int flags, CborType type, ConversionStatus *status);
169
170static CborError dump_bytestring_base16(char **result, CborValue *it)
171{
172 static const char characters[] = "0123456789abcdef";
173 size_t i;
174 size_t n = 0;
175 uint8_t *buffer;
176 CborError err = cbor_value_calculate_string_length(it, &n);
177 if (err)
178 return err;
179
180 /* a Base16 (hex) output is twice as big as our buffer */
181 buffer = (uint8_t *)malloc(n * 2 + 1);
182 *result = (char *)buffer;
183
184 /* let cbor_value_copy_byte_string know we have an extra byte for the terminating NUL */
185 ++n;
186 err = cbor_value_copy_byte_string(it, buffer + n - 1, &n, it);
187 cbor_assert(err == CborNoError);
188
189 for (i = 0; i < n; ++i) {
190 uint8_t byte = buffer[n + i];
191 buffer[2*i] = characters[byte >> 4];
192 buffer[2*i + 1] = characters[byte & 0xf];
193 }
194 return CborNoError;
195}
196
197static CborError generic_dump_base64(char **result, CborValue *it, const char alphabet[65])
198{
199 size_t n = 0, i;
200 uint8_t *buffer, *out, *in;
201 CborError err = cbor_value_calculate_string_length(it, &n);
202 if (err)
203 return err;
204
205 /* a Base64 output (untruncated) has 4 bytes for every 3 in the input */
206 size_t len = (n + 5) / 3 * 4;
207 out = buffer = (uint8_t *)malloc(len + 1);
208 *result = (char *)buffer;
209
210 /* we read our byte string at the tail end of the buffer
211 * so we can do an in-place conversion while iterating forwards */
212 in = buffer + len - n;
213
214 /* let cbor_value_copy_byte_string know we have an extra byte for the terminating NUL */
215 ++n;
216 err = cbor_value_copy_byte_string(it, in, &n, it);
217 cbor_assert(err == CborNoError);
218
219 uint_least32_t val = 0;
220 for (i = 0; n - i >= 3; i += 3) {
221 /* read 3 bytes x 8 bits = 24 bits */
222 if (false) {
223#ifdef __GNUC__
224 } else if (i) {
225 __builtin_memcpy(&val, in + i - 1, sizeof(val));
226 val = cbor_ntohl(val);
227#endif
228 } else {
229 val = (in[i] << 16) | (in[i + 1] << 8) | in[i + 2];
230 }
231
232 /* write 4 chars x 6 bits = 24 bits */
233 *out++ = alphabet[(val >> 18) & 0x3f];
234 *out++ = alphabet[(val >> 12) & 0x3f];
235 *out++ = alphabet[(val >> 6) & 0x3f];
236 *out++ = alphabet[val & 0x3f];
237 }
238
239 /* maybe 1 or 2 bytes left */
240 if (n - i) {
241 /* we can read in[i + 1] even if it's past the end of the string because
242 * we know (by construction) that it's a NUL byte */
243#ifdef __GNUC__
244 uint16_t val16;
245 __builtin_memcpy(&val16, in + i, sizeof(val16));
246 val = cbor_ntohs(val16);
247#else
248 val = (in[i] << 8) | in[i + 1];
249#endif
250 val <<= 8;
251
252 /* the 65th character in the alphabet is our filler: either '=' or '\0' */
253 out[4] = '\0';
254 out[3] = alphabet[64];
255 if (n - i == 2) {
256 /* write the third char in 3 chars x 6 bits = 18 bits */
257 out[2] = alphabet[(val >> 6) & 0x3f];
258 } else {
259 out[2] = alphabet[64]; /* filler */
260 }
261 out[1] = alphabet[(val >> 12) & 0x3f];
262 out[0] = alphabet[(val >> 18) & 0x3f];
263 } else {
264 out[0] = '\0';
265 }
266
267 return CborNoError;
268}
269
270static CborError dump_bytestring_base64(char **result, CborValue *it)
271{
272 static const char alphabet[] = "ABCDEFGH" "IJKLMNOP" "QRSTUVWX" "YZabcdef"
273 "ghijklmn" "opqrstuv" "wxyz0123" "456789+/" "=";
274 return generic_dump_base64(result, it, alphabet);
275}
276
277static CborError dump_bytestring_base64url(char **result, CborValue *it)
278{
279 static const char alphabet[] = "ABCDEFGH" "IJKLMNOP" "QRSTUVWX" "YZabcdef"
280 "ghijklmn" "opqrstuv" "wxyz0123" "456789-_";
281 return generic_dump_base64(result, it, alphabet);
282}
283
284static CborError add_value_metadata(FILE *out, CborType type, const ConversionStatus *status)
285{
286 int flags = status->flags;
287 if (flags & TypeWasTagged) {
288 /* extract the tagged type, which may be JSON native */
289 type = flags & FinalTypeMask;
290 flags &= ~(FinalTypeMask | TypeWasTagged);
291
292 if (fprintf(out, "\"tag\":\"%" PRIu64 "\"%s", status->lastTag,
293 flags & ~TypeWasTagged ? "," : "") < 0)
294 return CborErrorIO;
295 }
296
297 if (!flags)
298 return CborNoError;
299
300 /* print at least the type */
301 if (fprintf(out, "\"t\":%d", type) < 0)
302 return CborErrorIO;
303
304 if (flags & NumberWasNaN)
305 if (fprintf(out, ",\"v\":\"nan\"") < 0)
306 return CborErrorIO;
307 if (flags & NumberWasInfinite)
308 if (fprintf(out, ",\"v\":\"%sinf\"", flags & NumberWasNegative ? "-" : "") < 0)
309 return CborErrorIO;
310 if (flags & NumberPrecisionWasLost)
311 if (fprintf(out, ",\"v\":\"%c%" PRIx64 "\"", flags & NumberWasNegative ? '-' : '+',
312 status->originalNumber) < 0)
313 return CborErrorIO;
314 if (type == CborSimpleType)
315 if (fprintf(out, ",\"v\":%d", (int)status->originalNumber) < 0)
316 return CborErrorIO;
317 return CborNoError;
318}
319
320static CborError find_tagged_type(CborValue *it, CborTag *tag, CborType *type)
321{
322 CborError err = CborNoError;
323 *type = cbor_value_get_type(it);
324 while (*type == CborTagType) {
325 cbor_value_get_tag(it, tag); /* can't fail */
326 err = cbor_value_advance_fixed(it);
327 if (err)
328 return err;
329
330 *type = cbor_value_get_type(it);
331 }
332 return err;
333}
334
335static CborError tagged_value_to_json(FILE *out, CborValue *it, int flags, ConversionStatus *status)
336{
337 CborTag tag;
338 CborError err;
339
340 if (flags & CborConvertTagsToObjects) {
341 cbor_value_get_tag(it, &tag); /* can't fail */
342 err = cbor_value_advance_fixed(it);
343 if (err)
344 return err;
345
346 if (fprintf(out, "{\"tag%" PRIu64 "\":", tag) < 0)
347 return CborErrorIO;
348
349 CborType type = cbor_value_get_type(it);
350 err = value_to_json(out, it, flags, type, status);
351 if (err)
352 return err;
353 if (flags & CborConvertAddMetadata && status->flags) {
354 if (fprintf(out, ",\"tag%" PRIu64 "$cbor\":{", tag) < 0 ||
355 add_value_metadata(out, type, status) != CborNoError ||
356 fputc('}', out) < 0)
357 return CborErrorIO;
358 }
359 if (fputc('}', out) < 0)
360 return CborErrorIO;
361 status->flags = TypeWasNotNative | CborTagType;
362 return CborNoError;
363 }
364
365 CborType type;
366 err = find_tagged_type(it, &status->lastTag, &type);
367 if (err)
368 return err;
369 tag = status->lastTag;
370
371 /* special handling of byte strings? */
372 if (type == CborByteStringType && (flags & CborConvertByteStringsToBase64Url) == 0 &&
373 (tag == CborNegativeBignumTag || tag == CborExpectedBase16Tag || tag == CborExpectedBase64Tag)) {
374 char *str;
375 char *pre = "";
376
377 if (tag == CborNegativeBignumTag) {
378 pre = "~";
379 err = dump_bytestring_base64url(&str, it);
380 } else if (tag == CborExpectedBase64Tag) {
381 err = dump_bytestring_base64(&str, it);
382 } else { /* tag == CborExpectedBase16Tag */
383 err = dump_bytestring_base16(&str, it);
384 }
385 if (err)
386 return err;
387 err = fprintf(out, "\"%s%s\"", pre, str) < 0 ? CborErrorIO : CborNoError;
388 free(str);
389 status->flags = TypeWasNotNative | TypeWasTagged | CborByteStringType;
390 return err;
391 }
392
393 /* no special handling */
394 err = value_to_json(out, it, flags, type, status);
395 status->flags |= TypeWasTagged | type;
396 return err;
397}
398
399static CborError stringify_map_key(char **key, CborValue *it, int flags, CborType type)
400{
401 (void)flags; /* unused */
402 (void)type; /* unused */
403#ifdef WITHOUT_OPEN_MEMSTREAM
404 (void)key; /* unused */
405 (void)it; /* unused */
406 return CborErrorJsonNotImplemented;
407#else
408 size_t size;
409
410 FILE *memstream = open_memstream(key, &size);
411 if (memstream == NULL)
412 return CborErrorOutOfMemory; /* could also be EMFILE, but it's unlikely */
413 CborError err = cbor_value_to_pretty_advance(memstream, it);
414
415 if (unlikely(fclose(memstream) < 0 || *key == NULL))
416 return CborErrorInternalError;
417 return err;
418#endif
419}
420
421static CborError array_to_json(FILE *out, CborValue *it, int flags, ConversionStatus *status)
422{
423 const char *comma = "";
424 while (!cbor_value_at_end(it)) {
425 if (fprintf(out, "%s", comma) < 0)
426 return CborErrorIO;
427 comma = ",";
428
429 CborError err = value_to_json(out, it, flags, cbor_value_get_type(it), status);
430 if (err)
431 return err;
432 }
433 return CborNoError;
434}
435
436static CborError map_to_json(FILE *out, CborValue *it, int flags, ConversionStatus *status)
437{
438 const char *comma = "";
439 CborError err;
440 while (!cbor_value_at_end(it)) {
441 char *key;
442 if (fprintf(out, "%s", comma) < 0)
443 return CborErrorIO;
444 comma = ",";
445
446 CborType keyType = cbor_value_get_type(it);
447 if (likely(keyType == CborTextStringType)) {
448 size_t n = 0;
449 err = cbor_value_dup_text_string(it, &key, &n, it);
450 } else if (flags & CborConvertStringifyMapKeys) {
451 err = stringify_map_key(&key, it, flags, keyType);
452 } else {
453 return CborErrorJsonObjectKeyNotString;
454 }
455 if (err)
456 return err;
457
458 /* first, print the key */
459 if (fprintf(out, "\"%s\":", key) < 0) {
460 free(key);
461 return CborErrorIO;
462 }
463
464 /* then, print the value */
465 CborType valueType = cbor_value_get_type(it);
466 err = value_to_json(out, it, flags, valueType, status);
467
468 /* finally, print any metadata we may have */
469 if (flags & CborConvertAddMetadata) {
470 if (!err && keyType != CborTextStringType) {
471 if (fprintf(out, ",\"%s$keycbordump\":true", key) < 0)
472 err = CborErrorIO;
473 }
474 if (!err && status->flags) {
475 if (fprintf(out, ",\"%s$cbor\":{", key) < 0 ||
476 add_value_metadata(out, valueType, status) != CborNoError ||
477 fputc('}', out) < 0)
478 err = CborErrorIO;
479 }
480 }
481
482 free(key);
483 if (err)
484 return err;
485 }
486 return CborNoError;
487}
488
489static CborError value_to_json(FILE *out, CborValue *it, int flags, CborType type, ConversionStatus *status)
490{
491 CborError err;
492 status->flags = 0;
493
494 switch (type) {
495 case CborArrayType:
496 case CborMapType: {
497 /* recursive type */
498 CborValue recursed;
499 err = cbor_value_enter_container(it, &recursed);
500 if (err) {
501 it->ptr = recursed.ptr;
502 return err; /* parse error */
503 }
504 if (fputc(type == CborArrayType ? '[' : '{', out) < 0)
505 return CborErrorIO;
506
507 err = (type == CborArrayType) ?
508 array_to_json(out, &recursed, flags, status) :
509 map_to_json(out, &recursed, flags, status);
510 if (err) {
511 it->ptr = recursed.ptr;
512 return err; /* parse error */
513 }
514
515 if (fputc(type == CborArrayType ? ']' : '}', out) < 0)
516 return CborErrorIO;
517 err = cbor_value_leave_container(it, &recursed);
518 if (err)
519 return err; /* parse error */
520
521 status->flags = 0; /* reset, there are never conversion errors for us */
522 return CborNoError;
523 }
524
525 case CborIntegerType: {
526 double num; /* JS numbers are IEEE double precision */
527 uint64_t val;
528 cbor_value_get_raw_integer(it, &val); /* can't fail */
529 num = (double)val;
530
531 if (cbor_value_is_negative_integer(it)) {
532 num = -num - 1; /* convert to negative */
533 if ((uint64_t)(-num - 1) != val) {
534 status->flags = NumberPrecisionWasLost | NumberWasNegative;
535 status->originalNumber = val;
536 }
537 } else {
538 if ((uint64_t)num != val) {
539 status->flags = NumberPrecisionWasLost;
540 status->originalNumber = val;
541 }
542 }
543 if (fprintf(out, "%.0f", num) < 0) /* this number has no fraction, so no decimal points please */
544 return CborErrorIO;
545 break;
546 }
547
548 case CborByteStringType:
549 case CborTextStringType: {
550 char *str;
551 if (type == CborByteStringType) {
552 err = dump_bytestring_base64url(&str, it);
553 status->flags = TypeWasNotNative;
554 } else {
555 size_t n = 0;
556 err = cbor_value_dup_text_string(it, &str, &n, it);
557 }
558 if (err)
559 return err;
560 err = (fprintf(out, "\"%s\"", str) < 0) ? CborErrorIO : CborNoError;
561 free(str);
562 return err;
563 }
564
565 case CborTagType:
566 return tagged_value_to_json(out, it, flags, status);
567
568 case CborSimpleType: {
569 uint8_t simple_type;
570 cbor_value_get_simple_type(it, &simple_type); /* can't fail */
571 status->flags = TypeWasNotNative;
572 status->originalNumber = simple_type;
573 if (fprintf(out, "\"simple(%" PRIu8 ")\"", simple_type) < 0)
574 return CborErrorIO;
575 break;
576 }
577
578 case CborNullType:
579 if (fprintf(out, "null") < 0)
580 return CborErrorIO;
581 break;
582
583 case CborUndefinedType:
584 status->flags = TypeWasNotNative;
585 if (fprintf(out, "\"undefined\"") < 0)
586 return CborErrorIO;
587 break;
588
589 case CborBooleanType: {
590 bool val;
591 cbor_value_get_boolean(it, &val); /* can't fail */
592 if (fprintf(out, val ? "true" : "false") < 0)
593 return CborErrorIO;
594 break;
595 }
596
597#ifndef CBOR_NO_FLOATING_POINT
598 case CborDoubleType: {
599 double val;
600 if (false) {
601 float f;
602 case CborFloatType:
603 status->flags = TypeWasNotNative;
604 cbor_value_get_float(it, &f);
605 val = f;
606 } else if (false) {
607 uint16_t f16;
608 case CborHalfFloatType:
609# ifndef CBOR_NO_HALF_FLOAT_TYPE
610 status->flags = TypeWasNotNative;
611 cbor_value_get_half_float(it, &f16);
612 val = decode_half(f16);
613# else
614 (void)f16;
615 err = CborErrorUnsupportedType;
616 break;
617# endif
618 } else {
619 cbor_value_get_double(it, &val);
620 }
621
622 int r = fpclassify(val);
623 if (r == FP_NAN || r == FP_INFINITE) {
624 if (fprintf(out, "null") < 0)
625 return CborErrorIO;
626 status->flags |= r == FP_NAN ? NumberWasNaN :
627 NumberWasInfinite | (val < 0 ? NumberWasNegative : 0);
628 } else {
629 uint64_t ival = (uint64_t)fabs(val);
630 if ((double)ival == fabs(val)) {
631 /* print as integer so we get the full precision */
632 r = fprintf(out, "%s%" PRIu64, val < 0 ? "-" : "", ival);
633 status->flags |= TypeWasNotNative; /* mark this integer number as a double */
634 } else {
635 /* this number is definitely not a 64-bit integer */
636 r = fprintf(out, "%." DBL_DECIMAL_DIG_STR "g", val);
637 }
638 if (r < 0)
639 return CborErrorIO;
640 }
641 break;
642 }
643#else
644 case CborDoubleType:
645 case CborFloatType:
646 case CborHalfFloatType:
647 err = CborErrorUnsupportedType;
648 break;
649#endif /* !CBOR_NO_FLOATING_POINT */
650
651 case CborInvalidType:
652 return CborErrorUnknownType;
653 }
654
655 return cbor_value_advance_fixed(it);
656}
657
658/**
659 * \enum CborToJsonFlags
660 * The CborToJsonFlags enum contains flags that control the conversion of CBOR to JSON.
661 *
662 * \value CborConvertAddMetadata Adds metadata to facilitate restoration of the original CBOR data.
663 * \value CborConvertTagsToObjects Converts CBOR tags to JSON objects
664 * \value CborConvertIgnoreTags (default) Ignore CBOR tags, except for byte strings
665 * \value CborConvertObeyByteStringTags (default) Honor formatting of CBOR byte strings if so tagged
666 * \value CborConvertByteStringsToBase64Url Force the conversion of all CBOR byte strings to Base64url encoding, despite any tags
667 * \value CborConvertRequireMapStringKeys (default) Require CBOR map keys to be strings, failing the conversion if they are not
668 * \value CborConvertStringifyMapKeys Convert non-string keys in CBOR maps to a string form
669 * \value CborConvertDefaultFlags Default conversion flags.
670 */
671
672/**
673 * \fn CborError cbor_value_to_json(FILE *out, const CborValue *value, int flags)
674 *
675 * Converts the current CBOR type pointed to by \a value to JSON and writes that
676 * to the \a out stream. If an error occurs, this function returns an error
677 * code similar to CborParsing. The \a flags parameter indicates one or more of
678 * the flags from CborToJsonFlags that control the conversion.
679 *
680 * \sa cbor_value_to_json_advance(), cbor_value_to_pretty()
681 */
682
683/**
684 * Converts the current CBOR type pointed to by \a value to JSON and writes that
685 * to the \a out stream. If an error occurs, this function returns an error
686 * code similar to CborParsing. The \a flags parameter indicates one or more of
687 * the flags from CborToJsonFlags that control the conversion.
688 *
689 * If no error ocurred, this function advances \a value to the next element.
690 *
691 * \sa cbor_value_to_json(), cbor_value_to_pretty_advance()
692 */
693CborError cbor_value_to_json_advance(FILE *out, CborValue *value, int flags)
694{
695 ConversionStatus status;
696 return value_to_json(out, value, flags, cbor_value_get_type(value), &status);
697}
698
699/** @} */
Impressum, Datenschutz