github.com/google/syzkaller@v0.0.0-20240517125934-c0f1611a36d6/executor/_include/flatbuffers/util.h (about) 1 /* 2 * Copyright 2014 Google Inc. All rights reserved. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef FLATBUFFERS_UTIL_H_ 18 #define FLATBUFFERS_UTIL_H_ 19 20 #include <ctype.h> 21 #include <errno.h> 22 23 #include "flatbuffers/base.h" 24 #include "flatbuffers/stl_emulation.h" 25 26 #ifndef FLATBUFFERS_PREFER_PRINTF 27 # include <iomanip> 28 # include <sstream> 29 #else // FLATBUFFERS_PREFER_PRINTF 30 # include <float.h> 31 # include <stdio.h> 32 #endif // FLATBUFFERS_PREFER_PRINTF 33 34 #include <string> 35 36 namespace flatbuffers { 37 38 // @locale-independent functions for ASCII characters set. 39 40 // Fast checking that character lies in closed range: [a <= x <= b] 41 // using one compare (conditional branch) operator. 42 inline bool check_ascii_range(char x, char a, char b) { 43 FLATBUFFERS_ASSERT(a <= b); 44 // (Hacker's Delight): `a <= x <= b` <=> `(x-a) <={u} (b-a)`. 45 // The x, a, b will be promoted to int and subtracted without overflow. 46 return static_cast<unsigned int>(x - a) <= static_cast<unsigned int>(b - a); 47 } 48 49 // Case-insensitive isalpha 50 inline bool is_alpha(char c) { 51 // ASCII only: alpha to upper case => reset bit 0x20 (~0x20 = 0xDF). 52 return check_ascii_range(c & 0xDF, 'a' & 0xDF, 'z' & 0xDF); 53 } 54 55 // Check for uppercase alpha 56 inline bool is_alpha_upper(char c) { return check_ascii_range(c, 'A', 'Z'); } 57 58 // Check (case-insensitive) that `c` is equal to alpha. 59 inline bool is_alpha_char(char c, char alpha) { 60 FLATBUFFERS_ASSERT(is_alpha(alpha)); 61 // ASCII only: alpha to upper case => reset bit 0x20 (~0x20 = 0xDF). 62 return ((c & 0xDF) == (alpha & 0xDF)); 63 } 64 65 // https://en.cppreference.com/w/cpp/string/byte/isxdigit 66 // isdigit and isxdigit are the only standard narrow character classification 67 // functions that are not affected by the currently installed C locale. although 68 // some implementations (e.g. Microsoft in 1252 codepage) may classify 69 // additional single-byte characters as digits. 70 inline bool is_digit(char c) { return check_ascii_range(c, '0', '9'); } 71 72 inline bool is_xdigit(char c) { 73 // Replace by look-up table. 74 return is_digit(c) || check_ascii_range(c & 0xDF, 'a' & 0xDF, 'f' & 0xDF); 75 } 76 77 // Case-insensitive isalnum 78 inline bool is_alnum(char c) { return is_alpha(c) || is_digit(c); } 79 80 inline char CharToUpper(char c) { 81 return static_cast<char>(::toupper(static_cast<unsigned char>(c))); 82 } 83 84 inline char CharToLower(char c) { 85 return static_cast<char>(::tolower(static_cast<unsigned char>(c))); 86 } 87 88 // @end-locale-independent functions for ASCII character set 89 90 #ifdef FLATBUFFERS_PREFER_PRINTF 91 template<typename T> size_t IntToDigitCount(T t) { 92 size_t digit_count = 0; 93 // Count the sign for negative numbers 94 if (t < 0) digit_count++; 95 // Count a single 0 left of the dot for fractional numbers 96 if (-1 < t && t < 1) digit_count++; 97 // Count digits until fractional part 98 T eps = std::numeric_limits<T>::epsilon(); 99 while (t <= (-1 + eps) || (1 - eps) <= t) { 100 t /= 10; 101 digit_count++; 102 } 103 return digit_count; 104 } 105 106 template<typename T> size_t NumToStringWidth(T t, int precision = 0) { 107 size_t string_width = IntToDigitCount(t); 108 // Count the dot for floating point numbers 109 if (precision) string_width += (precision + 1); 110 return string_width; 111 } 112 113 template<typename T> 114 std::string NumToStringImplWrapper(T t, const char *fmt, int precision = 0) { 115 size_t string_width = NumToStringWidth(t, precision); 116 std::string s(string_width, 0x00); 117 // Allow snprintf to use std::string trailing null to detect buffer overflow 118 snprintf(const_cast<char *>(s.data()), (s.size() + 1), fmt, string_width, t); 119 return s; 120 } 121 #endif // FLATBUFFERS_PREFER_PRINTF 122 123 // Convert an integer or floating point value to a string. 124 // In contrast to std::stringstream, "char" values are 125 // converted to a string of digits, and we don't use scientific notation. 126 template<typename T> std::string NumToString(T t) { 127 // clang-format off 128 129 #ifndef FLATBUFFERS_PREFER_PRINTF 130 std::stringstream ss; 131 ss << t; 132 return ss.str(); 133 #else // FLATBUFFERS_PREFER_PRINTF 134 auto v = static_cast<long long>(t); 135 return NumToStringImplWrapper(v, "%.*lld"); 136 #endif // FLATBUFFERS_PREFER_PRINTF 137 // clang-format on 138 } 139 // Avoid char types used as character data. 140 template<> inline std::string NumToString<signed char>(signed char t) { 141 return NumToString(static_cast<int>(t)); 142 } 143 template<> inline std::string NumToString<unsigned char>(unsigned char t) { 144 return NumToString(static_cast<int>(t)); 145 } 146 template<> inline std::string NumToString<char>(char t) { 147 return NumToString(static_cast<int>(t)); 148 } 149 150 // Special versions for floats/doubles. 151 template<typename T> std::string FloatToString(T t, int precision) { 152 // clang-format off 153 154 #ifndef FLATBUFFERS_PREFER_PRINTF 155 // to_string() prints different numbers of digits for floats depending on 156 // platform and isn't available on Android, so we use stringstream 157 std::stringstream ss; 158 // Use std::fixed to suppress scientific notation. 159 ss << std::fixed; 160 // Default precision is 6, we want that to be higher for doubles. 161 ss << std::setprecision(precision); 162 ss << t; 163 auto s = ss.str(); 164 #else // FLATBUFFERS_PREFER_PRINTF 165 auto v = static_cast<double>(t); 166 auto s = NumToStringImplWrapper(v, "%0.*f", precision); 167 #endif // FLATBUFFERS_PREFER_PRINTF 168 // clang-format on 169 // Sadly, std::fixed turns "1" into "1.00000", so here we undo that. 170 auto p = s.find_last_not_of('0'); 171 if (p != std::string::npos) { 172 // Strip trailing zeroes. If it is a whole number, keep one zero. 173 s.resize(p + (s[p] == '.' ? 2 : 1)); 174 } 175 return s; 176 } 177 178 template<> inline std::string NumToString<double>(double t) { 179 return FloatToString(t, 12); 180 } 181 template<> inline std::string NumToString<float>(float t) { 182 return FloatToString(t, 6); 183 } 184 185 // Convert an integer value to a hexadecimal string. 186 // The returned string length is always xdigits long, prefixed by 0 digits. 187 // For example, IntToStringHex(0x23, 8) returns the string "00000023". 188 inline std::string IntToStringHex(int i, int xdigits) { 189 FLATBUFFERS_ASSERT(i >= 0); 190 // clang-format off 191 192 #ifndef FLATBUFFERS_PREFER_PRINTF 193 std::stringstream ss; 194 ss << std::setw(xdigits) << std::setfill('0') << std::hex << std::uppercase 195 << i; 196 return ss.str(); 197 #else // FLATBUFFERS_PREFER_PRINTF 198 return NumToStringImplWrapper(i, "%.*X", xdigits); 199 #endif // FLATBUFFERS_PREFER_PRINTF 200 // clang-format on 201 } 202 203 // clang-format off 204 // Use locale independent functions {strtod_l, strtof_l, strtoll_l, strtoull_l}. 205 #if defined(FLATBUFFERS_LOCALE_INDEPENDENT) && (FLATBUFFERS_LOCALE_INDEPENDENT > 0) 206 class ClassicLocale { 207 #ifdef _MSC_VER 208 typedef _locale_t locale_type; 209 #else 210 typedef locale_t locale_type; // POSIX.1-2008 locale_t type 211 #endif 212 ClassicLocale(); 213 ~ClassicLocale(); 214 locale_type locale_; 215 static ClassicLocale instance_; 216 public: 217 static locale_type Get() { return instance_.locale_; } 218 }; 219 220 #ifdef _MSC_VER 221 #define __strtoull_impl(s, pe, b) _strtoui64_l(s, pe, b, ClassicLocale::Get()) 222 #define __strtoll_impl(s, pe, b) _strtoi64_l(s, pe, b, ClassicLocale::Get()) 223 #define __strtod_impl(s, pe) _strtod_l(s, pe, ClassicLocale::Get()) 224 #define __strtof_impl(s, pe) _strtof_l(s, pe, ClassicLocale::Get()) 225 #else 226 #define __strtoull_impl(s, pe, b) strtoull_l(s, pe, b, ClassicLocale::Get()) 227 #define __strtoll_impl(s, pe, b) strtoll_l(s, pe, b, ClassicLocale::Get()) 228 #define __strtod_impl(s, pe) strtod_l(s, pe, ClassicLocale::Get()) 229 #define __strtof_impl(s, pe) strtof_l(s, pe, ClassicLocale::Get()) 230 #endif 231 #else 232 #define __strtod_impl(s, pe) strtod(s, pe) 233 #define __strtof_impl(s, pe) static_cast<float>(strtod(s, pe)) 234 #ifdef _MSC_VER 235 #define __strtoull_impl(s, pe, b) _strtoui64(s, pe, b) 236 #define __strtoll_impl(s, pe, b) _strtoi64(s, pe, b) 237 #else 238 #define __strtoull_impl(s, pe, b) strtoull(s, pe, b) 239 #define __strtoll_impl(s, pe, b) strtoll(s, pe, b) 240 #endif 241 #endif 242 243 inline void strtoval_impl(int64_t *val, const char *str, char **endptr, 244 int base) { 245 *val = __strtoll_impl(str, endptr, base); 246 } 247 248 inline void strtoval_impl(uint64_t *val, const char *str, char **endptr, 249 int base) { 250 *val = __strtoull_impl(str, endptr, base); 251 } 252 253 inline void strtoval_impl(double *val, const char *str, char **endptr) { 254 *val = __strtod_impl(str, endptr); 255 } 256 257 // UBSAN: double to float is safe if numeric_limits<float>::is_iec559 is true. 258 __suppress_ubsan__("float-cast-overflow") 259 inline void strtoval_impl(float *val, const char *str, char **endptr) { 260 *val = __strtof_impl(str, endptr); 261 } 262 #undef __strtoull_impl 263 #undef __strtoll_impl 264 #undef __strtod_impl 265 #undef __strtof_impl 266 // clang-format on 267 268 // Adaptor for strtoull()/strtoll(). 269 // Flatbuffers accepts numbers with any count of leading zeros (-009 is -9), 270 // while strtoll with base=0 interprets first leading zero as octal prefix. 271 // In future, it is possible to add prefixed 0b0101. 272 // 1) Checks errno code for overflow condition (out of range). 273 // 2) If base <= 0, function try to detect base of number by prefix. 274 // 275 // Return value (like strtoull and strtoll, but reject partial result): 276 // - If successful, an integer value corresponding to the str is returned. 277 // - If full string conversion can't be performed, 0 is returned. 278 // - If the converted value falls out of range of corresponding return type, a 279 // range error occurs. In this case value MAX(T)/MIN(T) is returned. 280 template<typename T> 281 inline bool StringToIntegerImpl(T *val, const char *const str, 282 const int base = 0, 283 const bool check_errno = true) { 284 // T is int64_t or uint64_T 285 FLATBUFFERS_ASSERT(str); 286 if (base <= 0) { 287 auto s = str; 288 while (*s && !is_digit(*s)) s++; 289 if (s[0] == '0' && is_alpha_char(s[1], 'X')) 290 return StringToIntegerImpl(val, str, 16, check_errno); 291 // if a prefix not match, try base=10 292 return StringToIntegerImpl(val, str, 10, check_errno); 293 } else { 294 if (check_errno) errno = 0; // clear thread-local errno 295 auto endptr = str; 296 strtoval_impl(val, str, const_cast<char **>(&endptr), base); 297 if ((*endptr != '\0') || (endptr == str)) { 298 *val = 0; // erase partial result 299 return false; // invalid string 300 } 301 // errno is out-of-range, return MAX/MIN 302 if (check_errno && errno) return false; 303 return true; 304 } 305 } 306 307 template<typename T> 308 inline bool StringToFloatImpl(T *val, const char *const str) { 309 // Type T must be either float or double. 310 FLATBUFFERS_ASSERT(str && val); 311 auto end = str; 312 strtoval_impl(val, str, const_cast<char **>(&end)); 313 auto done = (end != str) && (*end == '\0'); 314 if (!done) *val = 0; // erase partial result 315 return done; 316 } 317 318 // Convert a string to an instance of T. 319 // Return value (matched with StringToInteger64Impl and strtod): 320 // - If successful, a numeric value corresponding to the str is returned. 321 // - If full string conversion can't be performed, 0 is returned. 322 // - If the converted value falls out of range of corresponding return type, a 323 // range error occurs. In this case value MAX(T)/MIN(T) is returned. 324 template<typename T> inline bool StringToNumber(const char *s, T *val) { 325 // Assert on `unsigned long` and `signed long` on LP64. 326 // If it is necessary, it could be solved with flatbuffers::enable_if<B,T>. 327 static_assert(sizeof(T) < sizeof(int64_t), "unexpected type T"); 328 FLATBUFFERS_ASSERT(s && val); 329 int64_t i64; 330 // The errno check isn't needed, will return MAX/MIN on overflow. 331 if (StringToIntegerImpl(&i64, s, 0, false)) { 332 const int64_t max = (flatbuffers::numeric_limits<T>::max)(); 333 const int64_t min = flatbuffers::numeric_limits<T>::lowest(); 334 if (i64 > max) { 335 *val = static_cast<T>(max); 336 return false; 337 } 338 if (i64 < min) { 339 // For unsigned types return max to distinguish from 340 // "no conversion can be performed" when 0 is returned. 341 *val = static_cast<T>(flatbuffers::is_unsigned<T>::value ? max : min); 342 return false; 343 } 344 *val = static_cast<T>(i64); 345 return true; 346 } 347 *val = 0; 348 return false; 349 } 350 351 template<> inline bool StringToNumber<int64_t>(const char *str, int64_t *val) { 352 return StringToIntegerImpl(val, str); 353 } 354 355 template<> 356 inline bool StringToNumber<uint64_t>(const char *str, uint64_t *val) { 357 if (!StringToIntegerImpl(val, str)) return false; 358 // The strtoull accepts negative numbers: 359 // If the minus sign was part of the input sequence, the numeric value 360 // calculated from the sequence of digits is negated as if by unary minus 361 // in the result type, which applies unsigned integer wraparound rules. 362 // Fix this behaviour (except -0). 363 if (*val) { 364 auto s = str; 365 while (*s && !is_digit(*s)) s++; 366 s = (s > str) ? (s - 1) : s; // step back to one symbol 367 if (*s == '-') { 368 // For unsigned types return the max to distinguish from 369 // "no conversion can be performed". 370 *val = (flatbuffers::numeric_limits<uint64_t>::max)(); 371 return false; 372 } 373 } 374 return true; 375 } 376 377 template<> inline bool StringToNumber(const char *s, float *val) { 378 return StringToFloatImpl(val, s); 379 } 380 381 template<> inline bool StringToNumber(const char *s, double *val) { 382 return StringToFloatImpl(val, s); 383 } 384 385 inline int64_t StringToInt(const char *s, int base = 10) { 386 int64_t val; 387 return StringToIntegerImpl(&val, s, base) ? val : 0; 388 } 389 390 inline uint64_t StringToUInt(const char *s, int base = 10) { 391 uint64_t val; 392 return StringToIntegerImpl(&val, s, base) ? val : 0; 393 } 394 395 typedef bool (*LoadFileFunction)(const char *filename, bool binary, 396 std::string *dest); 397 typedef bool (*FileExistsFunction)(const char *filename); 398 399 LoadFileFunction SetLoadFileFunction(LoadFileFunction load_file_function); 400 401 FileExistsFunction SetFileExistsFunction( 402 FileExistsFunction file_exists_function); 403 404 // Check if file "name" exists. 405 bool FileExists(const char *name); 406 407 // Check if "name" exists and it is also a directory. 408 bool DirExists(const char *name); 409 410 // Load file "name" into "buf" returning true if successful 411 // false otherwise. If "binary" is false data is read 412 // using ifstream's text mode, otherwise data is read with 413 // no transcoding. 414 bool LoadFile(const char *name, bool binary, std::string *buf); 415 416 // Save data "buf" of length "len" bytes into a file 417 // "name" returning true if successful, false otherwise. 418 // If "binary" is false data is written using ifstream's 419 // text mode, otherwise data is written with no 420 // transcoding. 421 bool SaveFile(const char *name, const char *buf, size_t len, bool binary); 422 423 // Save data "buf" into file "name" returning true if 424 // successful, false otherwise. If "binary" is false 425 // data is written using ifstream's text mode, otherwise 426 // data is written with no transcoding. 427 inline bool SaveFile(const char *name, const std::string &buf, bool binary) { 428 return SaveFile(name, buf.c_str(), buf.size(), binary); 429 } 430 431 // Functionality for minimalistic portable path handling. 432 433 // The functions below behave correctly regardless of whether posix ('/') or 434 // Windows ('/' or '\\') separators are used. 435 436 // Any new separators inserted are always posix. 437 FLATBUFFERS_CONSTEXPR char kPathSeparator = '/'; 438 439 // Returns the path with the extension, if any, removed. 440 std::string StripExtension(const std::string &filepath); 441 442 // Returns the extension, if any. 443 std::string GetExtension(const std::string &filepath); 444 445 // Return the last component of the path, after the last separator. 446 std::string StripPath(const std::string &filepath); 447 448 // Strip the last component of the path + separator. 449 std::string StripFileName(const std::string &filepath); 450 451 std::string StripPrefix(const std::string &filepath, 452 const std::string &prefix_to_remove); 453 454 // Concatenates a path with a filename, regardless of whether the path 455 // ends in a separator or not. 456 std::string ConCatPathFileName(const std::string &path, 457 const std::string &filename); 458 459 // Replaces any '\\' separators with '/' 460 std::string PosixPath(const char *path); 461 std::string PosixPath(const std::string &path); 462 463 // This function ensure a directory exists, by recursively 464 // creating dirs for any parts of the path that don't exist yet. 465 void EnsureDirExists(const std::string &filepath); 466 467 // Obtains the absolute path from any other path. 468 // Returns the input path if the absolute path couldn't be resolved. 469 std::string AbsolutePath(const std::string &filepath); 470 471 // Returns files relative to the --project_root path, prefixed with `//`. 472 std::string RelativeToRootPath(const std::string &project, 473 const std::string &filepath); 474 475 // To and from UTF-8 unicode conversion functions 476 477 // Convert a unicode code point into a UTF-8 representation by appending it 478 // to a string. Returns the number of bytes generated. 479 inline int ToUTF8(uint32_t ucc, std::string *out) { 480 FLATBUFFERS_ASSERT(!(ucc & 0x80000000)); // Top bit can't be set. 481 // 6 possible encodings: http://en.wikipedia.org/wiki/UTF-8 482 for (int i = 0; i < 6; i++) { 483 // Max bits this encoding can represent. 484 uint32_t max_bits = 6 + i * 5 + static_cast<int>(!i); 485 if (ucc < (1u << max_bits)) { // does it fit? 486 // Remaining bits not encoded in the first byte, store 6 bits each 487 uint32_t remain_bits = i * 6; 488 // Store first byte: 489 (*out) += static_cast<char>((0xFE << (max_bits - remain_bits)) | 490 (ucc >> remain_bits)); 491 // Store remaining bytes: 492 for (int j = i - 1; j >= 0; j--) { 493 (*out) += static_cast<char>(((ucc >> (j * 6)) & 0x3F) | 0x80); 494 } 495 return i + 1; // Return the number of bytes added. 496 } 497 } 498 FLATBUFFERS_ASSERT(0); // Impossible to arrive here. 499 return -1; 500 } 501 502 // Converts whatever prefix of the incoming string corresponds to a valid 503 // UTF-8 sequence into a unicode code. The incoming pointer will have been 504 // advanced past all bytes parsed. 505 // returns -1 upon corrupt UTF-8 encoding (ignore the incoming pointer in 506 // this case). 507 inline int FromUTF8(const char **in) { 508 int len = 0; 509 // Count leading 1 bits. 510 for (int mask = 0x80; mask >= 0x04; mask >>= 1) { 511 if (**in & mask) { 512 len++; 513 } else { 514 break; 515 } 516 } 517 if ((static_cast<unsigned char>(**in) << len) & 0x80) 518 return -1; // Bit after leading 1's must be 0. 519 if (!len) return *(*in)++; 520 // UTF-8 encoded values with a length are between 2 and 4 bytes. 521 if (len < 2 || len > 4) { return -1; } 522 // Grab initial bits of the code. 523 int ucc = *(*in)++ & ((1 << (7 - len)) - 1); 524 for (int i = 0; i < len - 1; i++) { 525 if ((**in & 0xC0) != 0x80) return -1; // Upper bits must 1 0. 526 ucc <<= 6; 527 ucc |= *(*in)++ & 0x3F; // Grab 6 more bits of the code. 528 } 529 // UTF-8 cannot encode values between 0xD800 and 0xDFFF (reserved for 530 // UTF-16 surrogate pairs). 531 if (ucc >= 0xD800 && ucc <= 0xDFFF) { return -1; } 532 // UTF-8 must represent code points in their shortest possible encoding. 533 switch (len) { 534 case 2: 535 // Two bytes of UTF-8 can represent code points from U+0080 to U+07FF. 536 if (ucc < 0x0080 || ucc > 0x07FF) { return -1; } 537 break; 538 case 3: 539 // Three bytes of UTF-8 can represent code points from U+0800 to U+FFFF. 540 if (ucc < 0x0800 || ucc > 0xFFFF) { return -1; } 541 break; 542 case 4: 543 // Four bytes of UTF-8 can represent code points from U+10000 to U+10FFFF. 544 if (ucc < 0x10000 || ucc > 0x10FFFF) { return -1; } 545 break; 546 } 547 return ucc; 548 } 549 550 #ifndef FLATBUFFERS_PREFER_PRINTF 551 // Wraps a string to a maximum length, inserting new lines where necessary. Any 552 // existing whitespace will be collapsed down to a single space. A prefix or 553 // suffix can be provided, which will be inserted before or after a wrapped 554 // line, respectively. 555 inline std::string WordWrap(const std::string in, size_t max_length, 556 const std::string wrapped_line_prefix, 557 const std::string wrapped_line_suffix) { 558 std::istringstream in_stream(in); 559 std::string wrapped, line, word; 560 561 in_stream >> word; 562 line = word; 563 564 while (in_stream >> word) { 565 if ((line.length() + 1 + word.length() + wrapped_line_suffix.length()) < 566 max_length) { 567 line += " " + word; 568 } else { 569 wrapped += line + wrapped_line_suffix + "\n"; 570 line = wrapped_line_prefix + word; 571 } 572 } 573 wrapped += line; 574 575 return wrapped; 576 } 577 #endif // !FLATBUFFERS_PREFER_PRINTF 578 579 inline bool EscapeString(const char *s, size_t length, std::string *_text, 580 bool allow_non_utf8, bool natural_utf8) { 581 std::string &text = *_text; 582 text += "\""; 583 for (uoffset_t i = 0; i < length; i++) { 584 char c = s[i]; 585 switch (c) { 586 case '\n': text += "\\n"; break; 587 case '\t': text += "\\t"; break; 588 case '\r': text += "\\r"; break; 589 case '\b': text += "\\b"; break; 590 case '\f': text += "\\f"; break; 591 case '\"': text += "\\\""; break; 592 case '\\': text += "\\\\"; break; 593 default: 594 if (c >= ' ' && c <= '~') { 595 text += c; 596 } else { 597 // Not printable ASCII data. Let's see if it's valid UTF-8 first: 598 const char *utf8 = s + i; 599 int ucc = FromUTF8(&utf8); 600 if (ucc < 0) { 601 if (allow_non_utf8) { 602 text += "\\x"; 603 text += IntToStringHex(static_cast<uint8_t>(c), 2); 604 } else { 605 // There are two cases here: 606 // 607 // 1) We reached here by parsing an IDL file. In that case, 608 // we previously checked for non-UTF-8, so we shouldn't reach 609 // here. 610 // 611 // 2) We reached here by someone calling GenerateText() 612 // on a previously-serialized flatbuffer. The data might have 613 // non-UTF-8 Strings, or might be corrupt. 614 // 615 // In both cases, we have to give up and inform the caller 616 // they have no JSON. 617 return false; 618 } 619 } else { 620 if (natural_utf8) { 621 // utf8 points to past all utf-8 bytes parsed 622 text.append(s + i, static_cast<size_t>(utf8 - s - i)); 623 } else if (ucc <= 0xFFFF) { 624 // Parses as Unicode within JSON's \uXXXX range, so use that. 625 text += "\\u"; 626 text += IntToStringHex(ucc, 4); 627 } else if (ucc <= 0x10FFFF) { 628 // Encode Unicode SMP values to a surrogate pair using two \u 629 // escapes. 630 uint32_t base = ucc - 0x10000; 631 auto high_surrogate = (base >> 10) + 0xD800; 632 auto low_surrogate = (base & 0x03FF) + 0xDC00; 633 text += "\\u"; 634 text += IntToStringHex(high_surrogate, 4); 635 text += "\\u"; 636 text += IntToStringHex(low_surrogate, 4); 637 } 638 // Skip past characters recognized. 639 i = static_cast<uoffset_t>(utf8 - s - 1); 640 } 641 } 642 break; 643 } 644 } 645 text += "\""; 646 return true; 647 } 648 649 inline std::string BufferToHexText(const void *buffer, size_t buffer_size, 650 size_t max_length, 651 const std::string &wrapped_line_prefix, 652 const std::string &wrapped_line_suffix) { 653 std::string text = wrapped_line_prefix; 654 size_t start_offset = 0; 655 const char *s = reinterpret_cast<const char *>(buffer); 656 for (size_t i = 0; s && i < buffer_size; i++) { 657 // Last iteration or do we have more? 658 bool have_more = i + 1 < buffer_size; 659 text += "0x"; 660 text += IntToStringHex(static_cast<uint8_t>(s[i]), 2); 661 if (have_more) { text += ','; } 662 // If we have more to process and we reached max_length 663 if (have_more && 664 text.size() + wrapped_line_suffix.size() >= start_offset + max_length) { 665 text += wrapped_line_suffix; 666 text += '\n'; 667 start_offset = text.size(); 668 text += wrapped_line_prefix; 669 } 670 } 671 text += wrapped_line_suffix; 672 return text; 673 } 674 675 // Remove paired quotes in a string: "text"|'text' -> text. 676 std::string RemoveStringQuotes(const std::string &s); 677 678 // Change th global C-locale to locale with name <locale_name>. 679 // Returns an actual locale name in <_value>, useful if locale_name is "" or 680 // null. 681 bool SetGlobalTestLocale(const char *locale_name, 682 std::string *_value = nullptr); 683 684 // Read (or test) a value of environment variable. 685 bool ReadEnvironmentVariable(const char *var_name, 686 std::string *_value = nullptr); 687 688 // MSVC specific: Send all assert reports to STDOUT to prevent CI hangs. 689 void SetupDefaultCRTReportMode(); 690 691 enum class Case { 692 kUnknown = 0, 693 // TheQuickBrownFox 694 kUpperCamel = 1, 695 // theQuickBrownFox 696 kLowerCamel = 2, 697 // the_quick_brown_fox 698 kSnake = 3, 699 // THE_QUICK_BROWN_FOX 700 kScreamingSnake = 4, 701 // THEQUICKBROWNFOX 702 kAllUpper = 5, 703 // thequickbrownfox 704 kAllLower = 6, 705 // the-quick-brown-fox 706 kDasher = 7, 707 // THEQuiCKBr_ownFox (or whatever you want, we won't change it) 708 kKeep = 8, 709 // the_quick_brown_fox123 (as opposed to the_quick_brown_fox_123) 710 kSnake2 = 9, 711 }; 712 713 // Convert the `input` string of case `input_case` to the specified `output_case`. 714 std::string ConvertCase(const std::string &input, Case output_case, 715 Case input_case = Case::kSnake); 716 717 } // namespace flatbuffers 718 719 #endif // FLATBUFFERS_UTIL_H_