libcmo21/LibCmo/VTEncoding.cpp

257 lines
7.3 KiB
C++

#include "VTEncoding.hpp"
namespace LibCmo::EncodingHelper {
#pragma region assist functions
#if defined(LIBCMO_OS_WIN32)
#define LIBCMO_STR_EQUAL(a, b) strcmp(reinterpret_cast<const char*>(a), reinterpret_cast<const char*>(b)) == 0
bool GetWindowsCodePage(const char* u8_encoding_spec, UINT* result) {
if (LIBCMO_STR_EQUAL(u8_encoding_spec, u8"CP_ACP")) *result = CP_ACP;
else if (LIBCMO_STR_EQUAL(u8_encoding_spec, u8"CP_MACCP")) *result = CP_MACCP;
else if (LIBCMO_STR_EQUAL(u8_encoding_spec, u8"CP_OEMCP")) *result = CP_OEMCP;
else if (LIBCMO_STR_EQUAL(u8_encoding_spec, u8"CP_THREAD_ACPP")) *result = CP_THREAD_ACP;
else if (LIBCMO_STR_EQUAL(u8_encoding_spec, u8"CP_UTF8")) *result = CP_UTF8;
else {
char* pend = nullptr;
errno = 0;
uint64_t v = std::strtoull(u8_encoding_spec, &pend, 10);
if (pend == u8_encoding_spec || errno == ERANGE) return false;
*result = static_cast<UINT>(v);
}
return true;
}
#undef LIBCMO_STR_EQUAL
bool WcharToChar(const wchar_t* src, std::string& dest, const UINT codepage) {
int count, write_result;
//converter to CHAR
count = WideCharToMultiByte(codepage, 0, src, -1, NULL, 0, NULL, NULL);
if (count <= 0) return false;
dest.resize(count);
write_result = WideCharToMultiByte(codepage, 0, src, -1, dest.data(), count, NULL, NULL);
if (write_result <= 0) return false;
return true;
}
bool WcharToChar(const std::wstring& src, std::string& dest, const UINT codepage) {
return WcharToChar(src.c_str(), dest, codepage);
}
bool CharToWchar(const char* src, std::wstring& dest, const UINT codepage) {
int wcount, write_result;
// convert to WCHAR
wcount = MultiByteToWideChar(codepage, 0, src, -1, NULL, 0);
if (wcount <= 0) return false;
dest.resize(wcount);
write_result = MultiByteToWideChar(codepage, 0, src, -1, dest.data(), wcount);
if (write_result <= 0) return false;
return true;
}
bool CharToWchar(const std::string& src, std::wstring& dest, const UINT codepage) {
return CharToWchar(src.c_str(), dest, codepage);
}
bool CharToChar(const char* src, std::string& dest, const UINT src_codepage, const UINT dest_codepage) {
std::wstring intermediary;
if (!CharToWchar(src, intermediary, src_codepage)) return false;
if (!WcharToChar(intermediary, dest, dest_codepage)) return false;
return true;
}
bool CharToChar(const std::string& src, std::string& dest, const UINT src_codepage, const UINT dest_codepage) {
return CharToChar(src.c_str(), dest, src_codepage, dest_codepage);
}
#else
static constexpr const size_t IconvInc = 16;
static const iconv_t InvalidIconvDescriptor = reinterpret_cast<iconv_t>(-1);
bool CreateIconvDescriptor(const char* enc_from, const char* enc_to, iconv_t& val) {
val = iconv_open(enc_to, enc_from);
return val != InvalidIconvDescriptor;
}
void DestroyIconvDescriptor(iconv_t& val) {
if (val == InvalidIconvDescriptor) return;
iconv_close(val);
val = InvalidIconvDescriptor;
}
// Reference: https://stackoverflow.com/questions/13297458/simple-utf8-utf16-string-conversion-with-iconv
bool DoIconv(iconv_t& cd, const std::string& str_from, std::string& str_to) {
char *inbuf = nullptr, *outbuf = nullptr;
size_t inbytesleft, outbytesleft, nchars, result_len;
// check empty
if (str_from.empty()) {
str_to.clear();
return true;
}
// check iconv descriptor
if (cd == InvalidIconvDescriptor) {
// invalid iconv descriptor
return false;
}
// pre-resize
str_to.resize(str_from.size() + IconvInc);
// setup some variables
inbytesleft = str_from.size();
inbuf = const_cast<char*>(str_from.c_str());
outbytesleft = str_to.size();
outbuf = str_to.data();
result_len = str_to.size();
// conv core
nchars = iconv(cd, &inbuf, &inbytesleft, &outbuf, &outbytesleft);
while (nchars == (size_t)-1 && errno == E2BIG) {
// record the length has been converted
size_t len = outbuf - str_to.data();
// resize for variables
result_len += IconvInc;
outbytesleft += IconvInc;
// resize for container
str_to.resize(result_len);
// assign new outbuf from failed position
outbuf = str_to.data() + len;
nchars = iconv(cd, &inbuf, &inbytesleft, &outbuf, &outbytesleft);
}
// restore descriptor initial state
iconv(cd, nullptr, nullptr, nullptr, nullptr);
// check error
if (nchars == (size_t)-1) {
// failed
return false;
} else {
// success
// resize result to get correct data
str_to.resize(result_len - outbytesleft);
return true;
}
}
#endif
#pragma endregion
#pragma region core functions
#if defined(LIBCMO_OS_WIN32)
ENCODING_TOKEN CreateEncodingToken(const std::string& token_string) {
ENCODING_TOKEN token = new UINT();
if (!GetWindowsCodePage(token_string.c_str(), token)) {
*token = CP_ACP;
}
return token;
}
void DestroyEncodingToken(const ENCODING_TOKEN& token) {
if (token != ENCODING_TOKEN_DEFAULT) {
delete token;
}
}
bool GetUtf8VirtoolsName(const std::string& native_name, std::string& u8_name, const ENCODING_TOKEN& token) {
if (token == ENCODING_TOKEN_DEFAULT) return false;
return CharToChar(native_name, u8_name, *token, CP_UTF8);
}
bool GetNativeVirtoolsName(const std::string& u8_name, std::string& native_name, const ENCODING_TOKEN& token) {
if (token == ENCODING_TOKEN_DEFAULT) return false;
return CharToChar(u8_name, native_name, CP_UTF8, *token);
}
void SetStdPathFromU8Path(std::filesystem::path& stdpath, const char* u8_path) {
std::wstring intermediary;
if (CharToWchar(u8_path, intermediary, CP_UTF8)) {
stdpath = intermediary.c_str();
} else {
// fallback
stdpath = u8_path;
}
}
FILE* StdPathFOpen(std::filesystem::path& std_filepath, const char* u8_mode) {
std::wstring wmode;
if (CharToWchar(u8_mode, wmode, CP_UTF8)) {
return _wfopen(std_filepath.wstring().c_str(), wmode.c_str());
} else {
// fallback
return std::fopen(std_filepath.string().c_str(), u8_mode);
}
}
#else
IconvPair::IconvPair() :
FromUtf8(InvalidIconvDescriptor), ToUtf8(InvalidIconvDescriptor) {
}
IconvPair::~IconvPair() {
DestroyIconvDescriptor(this->FromUtf8);
DestroyIconvDescriptor(this->ToUtf8);
}
static constexpr const char UTF8_SYMBOL[] = "UTF-8";
ENCODING_TOKEN CreateEncodingToken(const std::string& token_string) {
ENCODING_TOKEN token = new IconvPair();
if (!CreateIconvDescriptor(UTF8_SYMBOL, token_string.c_str(), token->FromUtf8) ||
!CreateIconvDescriptor(token_string.c_str(), UTF8_SYMBOL, token->ToUtf8)) {
delete token;
return ENCODING_TOKEN_DEFAULT;
}
return token;
}
void DestroyEncodingToken(const ENCODING_TOKEN& token) {
if (token != ENCODING_TOKEN_DEFAULT) {
delete token;
}
}
bool GetUtf8VirtoolsName(const std::string& native_name, std::string& u8_name, const ENCODING_TOKEN& token) {
if (token == ENCODING_TOKEN_DEFAULT) return false;
return DoIconv(token->ToUtf8, native_name, u8_name);
}
bool GetNativeVirtoolsName(const std::string& u8_name, std::string& native_name, const ENCODING_TOKEN& token) {
if (token == ENCODING_TOKEN_DEFAULT) return false;
return DoIconv(token->FromUtf8, u8_name, native_name);
}
void SetStdPathFromU8Path(std::filesystem::path& stdpath, const char* u8_path) {
stdpath = u8_path;
}
FILE* StdPathFOpen(std::filesystem::path& std_filepath, const char* u8_mode) {
return std::fopen(u8_filepath.string().c_str(), u8_mode);
}
#endif
#pragma endregion
}