forked from google/flatbuffers
/
util.h
716 lines (637 loc) · 25.3 KB
/
util.h
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/*
* Copyright 2014 Google Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef FLATBUFFERS_UTIL_H_
#define FLATBUFFERS_UTIL_H_
#include <ctype.h>
#include <errno.h>
#include "flatbuffers/base.h"
#include "flatbuffers/stl_emulation.h"
#ifndef FLATBUFFERS_PREFER_PRINTF
# include <iomanip>
# include <sstream>
#else // FLATBUFFERS_PREFER_PRINTF
# include <float.h>
# include <stdio.h>
#endif // FLATBUFFERS_PREFER_PRINTF
#include <string>
namespace flatbuffers {
// @locale-independent functions for ASCII characters set.
// Fast checking that character lies in closed range: [a <= x <= b]
// using one compare (conditional branch) operator.
inline bool check_ascii_range(char x, char a, char b) {
FLATBUFFERS_ASSERT(a <= b);
// (Hacker's Delight): `a <= x <= b` <=> `(x-a) <={u} (b-a)`.
// The x, a, b will be promoted to int and subtracted without overflow.
return static_cast<unsigned int>(x - a) <= static_cast<unsigned int>(b - a);
}
// Case-insensitive isalpha
inline bool is_alpha(char c) {
// ASCII only: alpha to upper case => reset bit 0x20 (~0x20 = 0xDF).
return check_ascii_range(c & 0xDF, 'a' & 0xDF, 'z' & 0xDF);
}
// Check for uppercase alpha
inline bool is_alpha_upper(char c) { return check_ascii_range(c, 'A', 'Z'); }
// Check (case-insensitive) that `c` is equal to alpha.
inline bool is_alpha_char(char c, char alpha) {
FLATBUFFERS_ASSERT(is_alpha(alpha));
// ASCII only: alpha to upper case => reset bit 0x20 (~0x20 = 0xDF).
return ((c & 0xDF) == (alpha & 0xDF));
}
// https://en.cppreference.com/w/cpp/string/byte/isxdigit
// isdigit and isxdigit are the only standard narrow character classification
// functions that are not affected by the currently installed C locale. although
// some implementations (e.g. Microsoft in 1252 codepage) may classify
// additional single-byte characters as digits.
inline bool is_digit(char c) { return check_ascii_range(c, '0', '9'); }
inline bool is_xdigit(char c) {
// Replace by look-up table.
return is_digit(c) || check_ascii_range(c & 0xDF, 'a' & 0xDF, 'f' & 0xDF);
}
// Case-insensitive isalnum
inline bool is_alnum(char c) { return is_alpha(c) || is_digit(c); }
inline char CharToUpper(char c) {
return static_cast<char>(::toupper(static_cast<unsigned char>(c)));
}
inline char CharToLower(char c) {
return static_cast<char>(::tolower(static_cast<unsigned char>(c)));
}
// @end-locale-independent functions for ASCII character set
#ifdef FLATBUFFERS_PREFER_PRINTF
template<typename T> size_t IntToDigitCount(T t) {
size_t digit_count = 0;
// Count the sign for negative numbers
if (t < 0) digit_count++;
// Count a single 0 left of the dot for fractional numbers
if (-1 < t && t < 1) digit_count++;
// Count digits until fractional part
T eps = std::numeric_limits<T>::epsilon();
while (t <= (-1 + eps) || (1 - eps) <= t) {
t /= 10;
digit_count++;
}
return digit_count;
}
template<typename T> size_t NumToStringWidth(T t, int precision = 0) {
size_t string_width = IntToDigitCount(t);
// Count the dot for floating point numbers
if (precision) string_width += (precision + 1);
return string_width;
}
template<typename T>
std::string NumToStringImplWrapper(T t, const char *fmt, int precision = 0) {
size_t string_width = NumToStringWidth(t, precision);
std::string s(string_width, 0x00);
// Allow snprintf to use std::string trailing null to detect buffer overflow
snprintf(const_cast<char *>(s.data()), (s.size() + 1), fmt, string_width, t);
return s;
}
#endif // FLATBUFFERS_PREFER_PRINTF
// Convert an integer or floating point value to a string.
// In contrast to std::stringstream, "char" values are
// converted to a string of digits, and we don't use scientific notation.
template<typename T> std::string NumToString(T t) {
// clang-format off
#ifndef FLATBUFFERS_PREFER_PRINTF
std::stringstream ss;
ss << t;
return ss.str();
#else // FLATBUFFERS_PREFER_PRINTF
auto v = static_cast<long long>(t);
return NumToStringImplWrapper(v, "%.*lld");
#endif // FLATBUFFERS_PREFER_PRINTF
// clang-format on
}
// Avoid char types used as character data.
template<> inline std::string NumToString<signed char>(signed char t) {
return NumToString(static_cast<int>(t));
}
template<> inline std::string NumToString<unsigned char>(unsigned char t) {
return NumToString(static_cast<int>(t));
}
template<> inline std::string NumToString<char>(char t) {
return NumToString(static_cast<int>(t));
}
// Special versions for floats/doubles.
template<typename T> std::string FloatToString(T t, int precision) {
// clang-format off
#ifndef FLATBUFFERS_PREFER_PRINTF
// to_string() prints different numbers of digits for floats depending on
// platform and isn't available on Android, so we use stringstream
std::stringstream ss;
// Use std::fixed to suppress scientific notation.
ss << std::fixed;
// Default precision is 6, we want that to be higher for doubles.
ss << std::setprecision(precision);
ss << t;
auto s = ss.str();
#else // FLATBUFFERS_PREFER_PRINTF
auto v = static_cast<double>(t);
auto s = NumToStringImplWrapper(v, "%0.*f", precision);
#endif // FLATBUFFERS_PREFER_PRINTF
// clang-format on
// Sadly, std::fixed turns "1" into "1.00000", so here we undo that.
auto p = s.find_last_not_of('0');
if (p != std::string::npos) {
// Strip trailing zeroes. If it is a whole number, keep one zero.
s.resize(p + (s[p] == '.' ? 2 : 1));
}
return s;
}
template<> inline std::string NumToString<double>(double t) {
return FloatToString(t, 12);
}
template<> inline std::string NumToString<float>(float t) {
return FloatToString(t, 6);
}
// Convert an integer value to a hexadecimal string.
// The returned string length is always xdigits long, prefixed by 0 digits.
// For example, IntToStringHex(0x23, 8) returns the string "00000023".
inline std::string IntToStringHex(int i, int xdigits) {
FLATBUFFERS_ASSERT(i >= 0);
// clang-format off
#ifndef FLATBUFFERS_PREFER_PRINTF
std::stringstream ss;
ss << std::setw(xdigits) << std::setfill('0') << std::hex << std::uppercase
<< i;
return ss.str();
#else // FLATBUFFERS_PREFER_PRINTF
return NumToStringImplWrapper(i, "%.*X", xdigits);
#endif // FLATBUFFERS_PREFER_PRINTF
// clang-format on
}
// clang-format off
// Use locale independent functions {strtod_l, strtof_l, strtoll_l, strtoull_l}.
#if defined(FLATBUFFERS_LOCALE_INDEPENDENT) && (FLATBUFFERS_LOCALE_INDEPENDENT > 0)
class ClassicLocale {
#ifdef _MSC_VER
typedef _locale_t locale_type;
#else
typedef locale_t locale_type; // POSIX.1-2008 locale_t type
#endif
ClassicLocale();
~ClassicLocale();
locale_type locale_;
static ClassicLocale instance_;
public:
static locale_type Get() { return instance_.locale_; }
};
#ifdef _MSC_VER
#define __strtoull_impl(s, pe, b) _strtoui64_l(s, pe, b, ClassicLocale::Get())
#define __strtoll_impl(s, pe, b) _strtoi64_l(s, pe, b, ClassicLocale::Get())
#define __strtod_impl(s, pe) _strtod_l(s, pe, ClassicLocale::Get())
#define __strtof_impl(s, pe) _strtof_l(s, pe, ClassicLocale::Get())
#else
#define __strtoull_impl(s, pe, b) strtoull_l(s, pe, b, ClassicLocale::Get())
#define __strtoll_impl(s, pe, b) strtoll_l(s, pe, b, ClassicLocale::Get())
#define __strtod_impl(s, pe) strtod_l(s, pe, ClassicLocale::Get())
#define __strtof_impl(s, pe) strtof_l(s, pe, ClassicLocale::Get())
#endif
#else
#define __strtod_impl(s, pe) strtod(s, pe)
#define __strtof_impl(s, pe) static_cast<float>(strtod(s, pe))
#ifdef _MSC_VER
#define __strtoull_impl(s, pe, b) _strtoui64(s, pe, b)
#define __strtoll_impl(s, pe, b) _strtoi64(s, pe, b)
#else
#define __strtoull_impl(s, pe, b) strtoull(s, pe, b)
#define __strtoll_impl(s, pe, b) strtoll(s, pe, b)
#endif
#endif
inline void strtoval_impl(int64_t *val, const char *str, char **endptr,
int base) {
*val = __strtoll_impl(str, endptr, base);
}
inline void strtoval_impl(uint64_t *val, const char *str, char **endptr,
int base) {
*val = __strtoull_impl(str, endptr, base);
}
inline void strtoval_impl(double *val, const char *str, char **endptr) {
*val = __strtod_impl(str, endptr);
}
// UBSAN: double to float is safe if numeric_limits<float>::is_iec559 is true.
__suppress_ubsan__("float-cast-overflow")
inline void strtoval_impl(float *val, const char *str, char **endptr) {
*val = __strtof_impl(str, endptr);
}
#undef __strtoull_impl
#undef __strtoll_impl
#undef __strtod_impl
#undef __strtof_impl
// clang-format on
// Adaptor for strtoull()/strtoll().
// Flatbuffers accepts numbers with any count of leading zeros (-009 is -9),
// while strtoll with base=0 interprets first leading zero as octal prefix.
// In future, it is possible to add prefixed 0b0101.
// 1) Checks errno code for overflow condition (out of range).
// 2) If base <= 0, function try to detect base of number by prefix.
//
// Return value (like strtoull and strtoll, but reject partial result):
// - If successful, an integer value corresponding to the str is returned.
// - If full string conversion can't be performed, 0 is returned.
// - If the converted value falls out of range of corresponding return type, a
// range error occurs. In this case value MAX(T)/MIN(T) is returned.
template<typename T>
inline bool StringToIntegerImpl(T *val, const char *const str,
const int base = 0,
const bool check_errno = true) {
// T is int64_t or uint64_T
FLATBUFFERS_ASSERT(str);
if (base <= 0) {
auto s = str;
while (*s && !is_digit(*s)) s++;
if (s[0] == '0' && is_alpha_char(s[1], 'X'))
return StringToIntegerImpl(val, str, 16, check_errno);
// if a prefix not match, try base=10
return StringToIntegerImpl(val, str, 10, check_errno);
} else {
if (check_errno) errno = 0; // clear thread-local errno
auto endptr = str;
strtoval_impl(val, str, const_cast<char **>(&endptr), base);
if ((*endptr != '\0') || (endptr == str)) {
*val = 0; // erase partial result
return false; // invalid string
}
// errno is out-of-range, return MAX/MIN
if (check_errno && errno) return false;
return true;
}
}
template<typename T>
inline bool StringToFloatImpl(T *val, const char *const str) {
// Type T must be either float or double.
FLATBUFFERS_ASSERT(str && val);
auto end = str;
strtoval_impl(val, str, const_cast<char **>(&end));
auto done = (end != str) && (*end == '\0');
if (!done) *val = 0; // erase partial result
return done;
}
// Convert a string to an instance of T.
// Return value (matched with StringToInteger64Impl and strtod):
// - If successful, a numeric value corresponding to the str is returned.
// - If full string conversion can't be performed, 0 is returned.
// - If the converted value falls out of range of corresponding return type, a
// range error occurs. In this case value MAX(T)/MIN(T) is returned.
template<typename T> inline bool StringToNumber(const char *s, T *val) {
// Assert on `unsigned long` and `signed long` on LP64.
// If it is necessary, it could be solved with flatbuffers::enable_if<B,T>.
static_assert(sizeof(T) < sizeof(int64_t), "unexpected type T");
FLATBUFFERS_ASSERT(s && val);
int64_t i64;
// The errno check isn't needed, will return MAX/MIN on overflow.
if (StringToIntegerImpl(&i64, s, 0, false)) {
const int64_t max = (flatbuffers::numeric_limits<T>::max)();
const int64_t min = flatbuffers::numeric_limits<T>::lowest();
if (i64 > max) {
*val = static_cast<T>(max);
return false;
}
if (i64 < min) {
// For unsigned types return max to distinguish from
// "no conversion can be performed" when 0 is returned.
*val = static_cast<T>(flatbuffers::is_unsigned<T>::value ? max : min);
return false;
}
*val = static_cast<T>(i64);
return true;
}
*val = 0;
return false;
}
template<> inline bool StringToNumber<int64_t>(const char *str, int64_t *val) {
return StringToIntegerImpl(val, str);
}
template<>
inline bool StringToNumber<uint64_t>(const char *str, uint64_t *val) {
if (!StringToIntegerImpl(val, str)) return false;
// The strtoull accepts negative numbers:
// If the minus sign was part of the input sequence, the numeric value
// calculated from the sequence of digits is negated as if by unary minus
// in the result type, which applies unsigned integer wraparound rules.
// Fix this behaviour (except -0).
if (*val) {
auto s = str;
while (*s && !is_digit(*s)) s++;
s = (s > str) ? (s - 1) : s; // step back to one symbol
if (*s == '-') {
// For unsigned types return the max to distinguish from
// "no conversion can be performed".
*val = (flatbuffers::numeric_limits<uint64_t>::max)();
return false;
}
}
return true;
}
template<> inline bool StringToNumber(const char *s, float *val) {
return StringToFloatImpl(val, s);
}
template<> inline bool StringToNumber(const char *s, double *val) {
return StringToFloatImpl(val, s);
}
inline int64_t StringToInt(const char *s, int base = 10) {
int64_t val;
return StringToIntegerImpl(&val, s, base) ? val : 0;
}
inline uint64_t StringToUInt(const char *s, int base = 10) {
uint64_t val;
return StringToIntegerImpl(&val, s, base) ? val : 0;
}
typedef bool (*LoadFileFunction)(const char *filename, bool binary,
std::string *dest);
typedef bool (*FileExistsFunction)(const char *filename);
LoadFileFunction SetLoadFileFunction(LoadFileFunction load_file_function);
FileExistsFunction SetFileExistsFunction(
FileExistsFunction file_exists_function);
// Check if file "name" exists.
bool FileExists(const char *name);
// Check if "name" exists and it is also a directory.
bool DirExists(const char *name);
// Load file "name" into "buf" returning true if successful
// false otherwise. If "binary" is false data is read
// using ifstream's text mode, otherwise data is read with
// no transcoding.
bool LoadFile(const char *name, bool binary, std::string *buf);
// Save data "buf" of length "len" bytes into a file
// "name" returning true if successful, false otherwise.
// If "binary" is false data is written using ifstream's
// text mode, otherwise data is written with no
// transcoding.
bool SaveFile(const char *name, const char *buf, size_t len, bool binary);
// Save data "buf" into file "name" returning true if
// successful, false otherwise. If "binary" is false
// data is written using ifstream's text mode, otherwise
// data is written with no transcoding.
inline bool SaveFile(const char *name, const std::string &buf, bool binary) {
return SaveFile(name, buf.c_str(), buf.size(), binary);
}
// Functionality for minimalistic portable path handling.
// The functions below behave correctly regardless of whether posix ('/') or
// Windows ('/' or '\\') separators are used.
// Any new separators inserted are always posix.
FLATBUFFERS_CONSTEXPR char kPathSeparator = '/';
// Returns the path with the extension, if any, removed.
std::string StripExtension(const std::string &filepath);
// Returns the extension, if any.
std::string GetExtension(const std::string &filepath);
// Return the last component of the path, after the last separator.
std::string StripPath(const std::string &filepath);
// Strip the last component of the path + separator.
std::string StripFileName(const std::string &filepath);
std::string StripPrefix(const std::string &filepath,
const std::string &prefix_to_remove);
// Concatenates a path with a filename, regardless of whether the path
// ends in a separator or not.
std::string ConCatPathFileName(const std::string &path,
const std::string &filename);
// Replaces any '\\' separators with '/'
std::string PosixPath(const char *path);
std::string PosixPath(const std::string &path);
// This function ensure a directory exists, by recursively
// creating dirs for any parts of the path that don't exist yet.
void EnsureDirExists(const std::string &filepath);
// Obtains the absolute path from any other path.
// Returns the input path if the absolute path couldn't be resolved.
std::string AbsolutePath(const std::string &filepath);
// Returns files relative to the --project_root path, prefixed with `//`.
std::string RelativeToRootPath(const std::string &project,
const std::string &filepath);
// To and from UTF-8 unicode conversion functions
// Convert a unicode code point into a UTF-8 representation by appending it
// to a string. Returns the number of bytes generated.
inline int ToUTF8(uint32_t ucc, std::string *out) {
FLATBUFFERS_ASSERT(!(ucc & 0x80000000)); // Top bit can't be set.
// 6 possible encodings: http://en.wikipedia.org/wiki/UTF-8
for (int i = 0; i < 6; i++) {
// Max bits this encoding can represent.
uint32_t max_bits = 6 + i * 5 + static_cast<int>(!i);
if (ucc < (1u << max_bits)) { // does it fit?
// Remaining bits not encoded in the first byte, store 6 bits each
uint32_t remain_bits = i * 6;
// Store first byte:
(*out) += static_cast<char>((0xFE << (max_bits - remain_bits)) |
(ucc >> remain_bits));
// Store remaining bytes:
for (int j = i - 1; j >= 0; j--) {
(*out) += static_cast<char>(((ucc >> (j * 6)) & 0x3F) | 0x80);
}
return i + 1; // Return the number of bytes added.
}
}
FLATBUFFERS_ASSERT(0); // Impossible to arrive here.
return -1;
}
// Converts whatever prefix of the incoming string corresponds to a valid
// UTF-8 sequence into a unicode code. The incoming pointer will have been
// advanced past all bytes parsed.
// returns -1 upon corrupt UTF-8 encoding (ignore the incoming pointer in
// this case).
inline int FromUTF8(const char **in) {
int len = 0;
// Count leading 1 bits.
for (int mask = 0x80; mask >= 0x04; mask >>= 1) {
if (**in & mask) {
len++;
} else {
break;
}
}
if ((static_cast<unsigned char>(**in) << len) & 0x80)
return -1; // Bit after leading 1's must be 0.
if (!len) return *(*in)++;
// UTF-8 encoded values with a length are between 2 and 4 bytes.
if (len < 2 || len > 4) { return -1; }
// Grab initial bits of the code.
int ucc = *(*in)++ & ((1 << (7 - len)) - 1);
for (int i = 0; i < len - 1; i++) {
if ((**in & 0xC0) != 0x80) return -1; // Upper bits must 1 0.
ucc <<= 6;
ucc |= *(*in)++ & 0x3F; // Grab 6 more bits of the code.
}
// UTF-8 cannot encode values between 0xD800 and 0xDFFF (reserved for
// UTF-16 surrogate pairs).
if (ucc >= 0xD800 && ucc <= 0xDFFF) { return -1; }
// UTF-8 must represent code points in their shortest possible encoding.
switch (len) {
case 2:
// Two bytes of UTF-8 can represent code points from U+0080 to U+07FF.
if (ucc < 0x0080 || ucc > 0x07FF) { return -1; }
break;
case 3:
// Three bytes of UTF-8 can represent code points from U+0800 to U+FFFF.
if (ucc < 0x0800 || ucc > 0xFFFF) { return -1; }
break;
case 4:
// Four bytes of UTF-8 can represent code points from U+10000 to U+10FFFF.
if (ucc < 0x10000 || ucc > 0x10FFFF) { return -1; }
break;
}
return ucc;
}
#ifndef FLATBUFFERS_PREFER_PRINTF
// Wraps a string to a maximum length, inserting new lines where necessary. Any
// existing whitespace will be collapsed down to a single space. A prefix or
// suffix can be provided, which will be inserted before or after a wrapped
// line, respectively.
inline std::string WordWrap(const std::string in, size_t max_length,
const std::string wrapped_line_prefix,
const std::string wrapped_line_suffix) {
std::istringstream in_stream(in);
std::string wrapped, line, word;
in_stream >> word;
line = word;
while (in_stream >> word) {
if ((line.length() + 1 + word.length() + wrapped_line_suffix.length()) <
max_length) {
line += " " + word;
} else {
wrapped += line + wrapped_line_suffix + "\n";
line = wrapped_line_prefix + word;
}
}
wrapped += line;
return wrapped;
}
#endif // !FLATBUFFERS_PREFER_PRINTF
inline bool EscapeString(const char *s, size_t length, std::string *_text,
bool allow_non_utf8, bool natural_utf8) {
std::string &text = *_text;
text += "\"";
for (uoffset_t i = 0; i < length; i++) {
char c = s[i];
switch (c) {
case '\n': text += "\\n"; break;
case '\t': text += "\\t"; break;
case '\r': text += "\\r"; break;
case '\b': text += "\\b"; break;
case '\f': text += "\\f"; break;
case '\"': text += "\\\""; break;
case '\\': text += "\\\\"; break;
default:
if (c >= ' ' && c <= '~') {
text += c;
} else {
// Not printable ASCII data. Let's see if it's valid UTF-8 first:
const char *utf8 = s + i;
int ucc = FromUTF8(&utf8);
if (ucc < 0) {
if (allow_non_utf8) {
text += "\\x";
text += IntToStringHex(static_cast<uint8_t>(c), 2);
} else {
// There are two cases here:
//
// 1) We reached here by parsing an IDL file. In that case,
// we previously checked for non-UTF-8, so we shouldn't reach
// here.
//
// 2) We reached here by someone calling GenerateText()
// on a previously-serialized flatbuffer. The data might have
// non-UTF-8 Strings, or might be corrupt.
//
// In both cases, we have to give up and inform the caller
// they have no JSON.
return false;
}
} else {
if (natural_utf8) {
// utf8 points to past all utf-8 bytes parsed
text.append(s + i, static_cast<size_t>(utf8 - s - i));
} else if (ucc <= 0xFFFF) {
// Parses as Unicode within JSON's \uXXXX range, so use that.
text += "\\u";
text += IntToStringHex(ucc, 4);
} else if (ucc <= 0x10FFFF) {
// Encode Unicode SMP values to a surrogate pair using two \u
// escapes.
uint32_t base = ucc - 0x10000;
auto high_surrogate = (base >> 10) + 0xD800;
auto low_surrogate = (base & 0x03FF) + 0xDC00;
text += "\\u";
text += IntToStringHex(high_surrogate, 4);
text += "\\u";
text += IntToStringHex(low_surrogate, 4);
}
// Skip past characters recognized.
i = static_cast<uoffset_t>(utf8 - s - 1);
}
}
break;
}
}
text += "\"";
return true;
}
inline std::string BufferToHexText(const void *buffer, size_t buffer_size,
size_t max_length,
const std::string &wrapped_line_prefix,
const std::string &wrapped_line_suffix) {
std::string text = wrapped_line_prefix;
size_t start_offset = 0;
const char *s = reinterpret_cast<const char *>(buffer);
for (size_t i = 0; s && i < buffer_size; i++) {
// Last iteration or do we have more?
bool have_more = i + 1 < buffer_size;
text += "0x";
text += IntToStringHex(static_cast<uint8_t>(s[i]), 2);
if (have_more) { text += ','; }
// If we have more to process and we reached max_length
if (have_more &&
text.size() + wrapped_line_suffix.size() >= start_offset + max_length) {
text += wrapped_line_suffix;
text += '\n';
start_offset = text.size();
text += wrapped_line_prefix;
}
}
text += wrapped_line_suffix;
return text;
}
// Remove paired quotes in a string: "text"|'text' -> text.
std::string RemoveStringQuotes(const std::string &s);
// Change th global C-locale to locale with name <locale_name>.
// Returns an actual locale name in <_value>, useful if locale_name is "" or
// null.
bool SetGlobalTestLocale(const char *locale_name,
std::string *_value = nullptr);
// Read (or test) a value of environment variable.
bool ReadEnvironmentVariable(const char *var_name,
std::string *_value = nullptr);
enum class Case {
kUnknown = 0,
// TheQuickBrownFox
kUpperCamel = 1,
// theQuickBrownFox
kLowerCamel = 2,
// the_quick_brown_fox
kSnake = 3,
// THE_QUICK_BROWN_FOX
kScreamingSnake = 4,
// THEQUICKBROWNFOX
kAllUpper = 5,
// thequickbrownfox
kAllLower = 6,
// the-quick-brown-fox
kDasher = 7,
// THEQuiCKBr_ownFox (or whatever you want, we won't change it)
kKeep = 8,
// the_quick_brown_fox123 (as opposed to the_quick_brown_fox_123)
kSnake2 = 9,
};
// Convert the `input` string of case `input_case` to the specified `output_case`.
std::string ConvertCase(const std::string &input, Case output_case,
Case input_case = Case::kSnake);
} // namespace flatbuffers
#endif // FLATBUFFERS_UTIL_H_