1/****************************************************************************
2**
3** Copyright (C) 2021 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#ifndef CBORINTERNAL_P_H
26#define CBORINTERNAL_P_H
27
28#include "compilersupport_p.h"
29
30#ifndef CBOR_NO_FLOATING_POINT
31# include <float.h>
32# include <math.h>
33#else
34# ifndef CBOR_NO_HALF_FLOAT_TYPE
35# define CBOR_NO_HALF_FLOAT_TYPE 1
36# endif
37#endif
38
39#ifndef CBOR_NO_HALF_FLOAT_TYPE
40# if defined(__F16C__) || defined(__AVX2__)
41# include <immintrin.h>
42static inline unsigned short encode_half(float val)
43{
44 __m128i m = _mm_cvtps_ph(_mm_set_ss(val), _MM_FROUND_CUR_DIRECTION);
45 return _mm_extract_epi16(m, 0);
46}
47static inline float decode_half(unsigned short half)
48{
49 __m128i m = _mm_cvtsi32_si128(half);
50 return _mm_cvtss_f32(_mm_cvtph_ps(m));
51}
52# else
53/* software implementation of float-to-fp16 conversions */
54static inline unsigned short encode_half(double val)
55{
56 uint64_t v;
57 int sign, exp, mant;
58 memcpy(dest: &v, src: &val, n: sizeof(v));
59 sign = v >> 63 << 15;
60 exp = (v >> 52) & 0x7ff;
61 mant = v << 12 >> 12 >> (53-11); /* keep only the 11 most significant bits of the mantissa */
62 exp -= 1023;
63 if (exp == 1024) {
64 /* infinity or NaN */
65 exp = 16;
66 mant >>= 1;
67 } else if (exp >= 16) {
68 /* overflow, as largest number */
69 exp = 15;
70 mant = 1023;
71 } else if (exp >= -14) {
72 /* regular normal */
73 } else if (exp >= -24) {
74 /* subnormal */
75 mant |= 1024;
76 mant >>= -(exp + 14);
77 exp = -15;
78 } else {
79 /* underflow, make zero */
80 return 0;
81 }
82
83 /* safe cast here as bit operations above guarantee not to overflow */
84 return (unsigned short)(sign | ((exp + 15) << 10) | mant);
85}
86
87/* this function was copied & adapted from RFC 7049 Appendix D */
88static inline double decode_half(unsigned short half)
89{
90 int exp = (half >> 10) & 0x1f;
91 int mant = half & 0x3ff;
92 double val;
93 if (exp == 0) val = ldexp(x: mant, exp: -24);
94 else if (exp != 31) val = ldexp(x: mant + 1024, exp: exp - 25);
95 else val = mant == 0 ? INFINITY : NAN;
96 return half & 0x8000 ? -val : val;
97}
98# endif
99#endif /* CBOR_NO_HALF_FLOAT_TYPE */
100
101#ifndef CBOR_INTERNAL_API
102# define CBOR_INTERNAL_API
103#endif
104
105#ifndef CBOR_PARSER_MAX_RECURSIONS
106# define CBOR_PARSER_MAX_RECURSIONS 1024
107#endif
108
109#ifndef CBOR_ENCODER_WRITER_CONTROL
110# define CBOR_ENCODER_WRITER_CONTROL 0
111#endif
112#ifndef CBOR_PARSER_READER_CONTROL
113# define CBOR_PARSER_READER_CONTROL 0
114#endif
115
116/*
117 * CBOR Major types
118 * Encoded in the high 3 bits of the descriptor byte
119 * See http://tools.ietf.org/html/rfc7049#section-2.1
120 */
121typedef enum CborMajorTypes {
122 UnsignedIntegerType = 0U,
123 NegativeIntegerType = 1U,
124 ByteStringType = 2U,
125 TextStringType = 3U,
126 ArrayType = 4U,
127 MapType = 5U, /* a.k.a. object */
128 TagType = 6U,
129 SimpleTypesType = 7U
130} CborMajorTypes;
131
132/*
133 * CBOR simple and floating point types
134 * Encoded in the low 8 bits of the descriptor byte when the
135 * Major Type is 7.
136 */
137typedef enum CborSimpleTypes {
138 FalseValue = 20,
139 TrueValue = 21,
140 NullValue = 22,
141 UndefinedValue = 23,
142 SimpleTypeInNextByte = 24, /* not really a simple type */
143 HalfPrecisionFloat = 25, /* ditto */
144 SinglePrecisionFloat = 26, /* ditto */
145 DoublePrecisionFloat = 27, /* ditto */
146 Break = 31
147} CborSimpleTypes;
148
149enum {
150 SmallValueBitLength = 5U,
151 SmallValueMask = (1U << SmallValueBitLength) - 1, /* 31 */
152 Value8Bit = 24U,
153 Value16Bit = 25U,
154 Value32Bit = 26U,
155 Value64Bit = 27U,
156 IndefiniteLength = 31U,
157
158 MajorTypeShift = SmallValueBitLength,
159 MajorTypeMask = (int) (~0U << MajorTypeShift),
160
161 BreakByte = (unsigned)Break | (SimpleTypesType << MajorTypeShift)
162};
163
164static inline void copy_current_position(CborValue *dst, const CborValue *src)
165{
166 /* This "if" is here for pedantry only: the two branches should perform
167 * the same memory operation. */
168 if (src->parser->flags & CborParserFlag_ExternalSource)
169 dst->source.token = src->source.token;
170 else
171 dst->source.ptr = src->source.ptr;
172}
173
174static inline bool can_read_bytes(const CborValue *it, size_t n)
175{
176 if (CBOR_PARSER_READER_CONTROL >= 0) {
177 if (it->parser->flags & CborParserFlag_ExternalSource || CBOR_PARSER_READER_CONTROL != 0) {
178#ifdef CBOR_PARSER_CAN_READ_BYTES_FUNCTION
179 return CBOR_PARSER_CAN_READ_BYTES_FUNCTION(it->source.token, n);
180#else
181 return it->parser->source.ops->can_read_bytes(it->source.token, n);
182#endif
183 }
184 }
185
186 /* Convert the pointer subtraction to size_t since end >= ptr
187 * (this prevents issues with (ptrdiff_t)n becoming negative).
188 */
189 return (size_t)(it->parser->source.end - it->source.ptr) >= n;
190}
191
192static inline void advance_bytes(CborValue *it, size_t n)
193{
194 if (CBOR_PARSER_READER_CONTROL >= 0) {
195 if (it->parser->flags & CborParserFlag_ExternalSource || CBOR_PARSER_READER_CONTROL != 0) {
196#ifdef CBOR_PARSER_ADVANCE_BYTES_FUNCTION
197 CBOR_PARSER_ADVANCE_BYTES_FUNCTION(it->source.token, n);
198#else
199 it->parser->source.ops->advance_bytes(it->source.token, n);
200#endif
201 return;
202 }
203 }
204
205 it->source.ptr += n;
206}
207
208static inline CborError transfer_string(CborValue *it, const void **ptr, size_t offset, size_t len)
209{
210 if (CBOR_PARSER_READER_CONTROL >= 0) {
211 if (it->parser->flags & CborParserFlag_ExternalSource || CBOR_PARSER_READER_CONTROL != 0) {
212#ifdef CBOR_PARSER_TRANSFER_STRING_FUNCTION
213 return CBOR_PARSER_TRANSFER_STRING_FUNCTION(it->source.token, ptr, offset, len);
214#else
215 return it->parser->source.ops->transfer_string(it->source.token, ptr, offset, len);
216#endif
217 }
218 }
219
220 it->source.ptr += offset;
221 if (can_read_bytes(it, n: len)) {
222 *CONST_CAST(const void **, ptr) = it->source.ptr;
223 it->source.ptr += len;
224 return CborNoError;
225 }
226 return CborErrorUnexpectedEOF;
227}
228
229static inline void *read_bytes_unchecked(const CborValue *it, void *dst, size_t offset, size_t n)
230{
231 if (CBOR_PARSER_READER_CONTROL >= 0) {
232 if (it->parser->flags & CborParserFlag_ExternalSource || CBOR_PARSER_READER_CONTROL != 0) {
233#ifdef CBOR_PARSER_READ_BYTES_FUNCTION
234 return CBOR_PARSER_READ_BYTES_FUNCTION(it->source.token, dst, offset, n);
235#else
236 return it->parser->source.ops->read_bytes(it->source.token, dst, offset, n);
237#endif
238 }
239 }
240
241 return memcpy(dest: dst, src: it->source.ptr + offset, n: n);
242}
243
244#ifdef __GNUC__
245__attribute__((warn_unused_result))
246#endif
247static inline void *read_bytes(const CborValue *it, void *dst, size_t offset, size_t n)
248{
249 if (can_read_bytes(it, n: offset + n))
250 return read_bytes_unchecked(it, dst, offset, n);
251 return NULL;
252}
253
254static inline uint16_t read_uint8(const CborValue *it, size_t offset)
255{
256 uint8_t result;
257 read_bytes_unchecked(it, dst: &result, offset, n: sizeof(result));
258 return result;
259}
260
261static inline uint16_t read_uint16(const CborValue *it, size_t offset)
262{
263 uint16_t result;
264 read_bytes_unchecked(it, dst: &result, offset, n: sizeof(result));
265 return cbor_ntohs(result);
266}
267
268static inline uint32_t read_uint32(const CborValue *it, size_t offset)
269{
270 uint32_t result;
271 read_bytes_unchecked(it, dst: &result, offset, n: sizeof(result));
272 return cbor_ntohl(result);
273}
274
275static inline uint64_t read_uint64(const CborValue *it, size_t offset)
276{
277 uint64_t result;
278 read_bytes_unchecked(it, dst: &result, offset, n: sizeof(result));
279 return cbor_ntohll(result);
280}
281
282static inline CborError extract_number_checked(const CborValue *it, uint64_t *value, size_t *bytesUsed)
283{
284 uint8_t descriptor;
285 size_t bytesNeeded = 0;
286
287 /* We've already verified that there's at least one byte to be read */
288 read_bytes_unchecked(it, dst: &descriptor, offset: 0, n: 1);
289 descriptor &= SmallValueMask;
290 if (descriptor < Value8Bit) {
291 *value = descriptor;
292 } else if (unlikely(descriptor > Value64Bit)) {
293 return CborErrorIllegalNumber;
294 } else {
295 bytesNeeded = (size_t)(1 << (descriptor - Value8Bit));
296 if (!can_read_bytes(it, n: 1 + bytesNeeded))
297 return CborErrorUnexpectedEOF;
298 if (descriptor <= Value16Bit) {
299 if (descriptor == Value16Bit)
300 *value = read_uint16(it, offset: 1);
301 else
302 *value = read_uint8(it, offset: 1);
303 } else {
304 if (descriptor == Value32Bit)
305 *value = read_uint32(it, offset: 1);
306 else
307 *value = read_uint64(it, offset: 1);
308 }
309 }
310
311 if (bytesUsed)
312 *bytesUsed = bytesNeeded;
313 return CborNoError;
314}
315
316#endif /* CBORINTERNAL_P_H */
317

source code of qtbase/src/3rdparty/tinycbor/src/cborinternal_p.h