Files
Cocos2d-Lua-Community/external/flatbuffers/util.h
2019-12-11 14:33:08 +08:00

244 lines
8.0 KiB
C++

/*
* 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 <fstream>
#include <iomanip>
#include <string>
#include <sstream>
#include <stdlib.h>
#include <assert.h>
#ifdef _WIN32
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#ifndef NOMINMAX
#define NOMINMAX
#endif
#include <windows.h>
#include <winbase.h>
#include <direct.h>
#else
#include <sys/stat.h>
#include <limits.h>
#endif
namespace flatbuffers {
// Convert an integer or floating point value to a string.
// In contrast to std::stringstream, "char" values are
// converted to a string of digits.
template<typename T> std::string NumToString(T t) {
// 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;
ss << t;
return ss.str();
}
// 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));
}
// 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) {
std::stringstream ss;
ss << std::setw(xdigits)
<< std::setfill('0')
<< std::hex
<< std::uppercase
<< i;
return ss.str();
}
// Portable implementation of strtoull().
inline int64_t StringToInt(const char *str, int base = 10) {
#ifdef _MSC_VER
return _strtoui64(str, nullptr, base);
#else
return strtoull(str, nullptr, base);
#endif
}
// 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.
inline bool LoadFile(const char *name, bool binary, std::string *buf) {
std::ifstream ifs(name, binary ? std::ifstream::binary : std::ifstream::in);
if (!ifs.is_open()) return false;
*buf = std::string(std::istreambuf_iterator<char>(ifs),
std::istreambuf_iterator<char>());
return !ifs.bad();
}
// 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.
inline bool SaveFile(const char *name, const char *buf, size_t len,
bool binary) {
std::ofstream ofs(name, binary ? std::ofstream::binary : std::ofstream::out);
if (!ofs.is_open()) return false;
ofs.write(buf, len);
return !ofs.bad();
}
// 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:
static const char kPosixPathSeparator = '/';
#ifdef _WIN32
static const char kPathSeparator = '\\';
static const char *PathSeparatorSet = "\\/"; // Intentionally no ':'
#else
static const char kPathSeparator = kPosixPathSeparator;
static const char *PathSeparatorSet = "/";
#endif // _WIN32
// Returns the path with the extension, if any, removed.
inline std::string StripExtension(const std::string &filepath) {
size_t i = filepath.find_last_of(".");
return i != std::string::npos ? filepath.substr(0, i) : filepath;
}
// Return the last component of the path, after the last separator.
inline std::string StripPath(const std::string &filepath) {
size_t i = filepath.find_last_of(PathSeparatorSet);
return i != std::string::npos ? filepath.substr(i + 1) : filepath;
}
// Strip the last component of the path + separator.
inline std::string StripFileName(const std::string &filepath) {
size_t i = filepath.find_last_of(PathSeparatorSet);
return i != std::string::npos ? filepath.substr(0, i) : "";
}
// Concatenates a path with a filename, regardless of wether the path
// ends in a separator or not.
inline std::string ConCatPathFileName(const std::string &path,
const std::string &filename) {
std::string filepath = path;
if (path.length() && path.back() != kPathSeparator &&
path.back() != kPosixPathSeparator)
filepath += kPathSeparator;
filepath += filename;
return filepath;
}
// This function ensure a directory exists, by recursively
// creating dirs for any parts of the path that don't exist yet.
inline void EnsureDirExists(const std::string &filepath) {
auto parent = StripFileName(filepath);
if (parent.length()) EnsureDirExists(parent);
#ifdef _WIN32
_mkdir(filepath.c_str());
#else
mkdir(filepath.c_str(), S_IRWXU|S_IRGRP|S_IXGRP);
#endif
}
// Obtains the absolute path from any other path.
// Returns the input path if the absolute path couldn't be resolved.
inline std::string AbsolutePath(const std::string &filepath) {
#ifdef _WIN32
char abs_path[MAX_PATH];
#if defined(WP8) || defined(WINRT)
return 0
#else
return GetFullPathNameA(filepath.c_str(), MAX_PATH, abs_path, nullptr)
#endif
#else
char abs_path[PATH_MAX];
return realpath(filepath.c_str(), abs_path)
#endif
? abs_path
: 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) {
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.
}
}
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 ((**in << len) & 0x80) return -1; // Bit after leading 1's must be 0.
if (!len) return *(*in)++;
// 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.
}
return ucc;
}
} // namespace flatbuffers
#endif // FLATBUFFERS_UTIL_H_